Translation & docs update

Update protocol dependency
Merge pull request #2169 from calmh/restartmon
2015-08-23 12:03:28 +02:00 · 2015-08-20 12:14:47 +02:00 · 2015-08-19 23:16:32 +02:00 · 2015-08-19 20:11:19 +01:00 · 2015-08-19 20:25:24 +02:00 · 2015-08-19 17:23:50 +02:00
424 changed files with 21649 additions and 8026 deletions
@@ -3,30 +3,37 @@
 Aaron Bieber <qbit@deftly.net>
 Alexander Graf <register-github@alex-graf.de>
 Andrew Dunham <andrew@du.nham.ca>
-Audrius Butkevicius <audrius.butkevicius@gmail.com>
+Antony Male <antony.male@gmail.com>
 Arthur Axel fREW Schmidt <frew@afoolishmanifesto.com> <frioux@gmail.com>
+Audrius Butkevicius <audrius.butkevicius@gmail.com>
 Bart De Vries <devriesb@gmail.com>
 Ben Curthoys <ben@bencurthoys.com>
 Ben Schulz <ueomkail@gmail.com> <uok@users.noreply.github.com>
 Ben Sidhom <bsidhom@gmail.com>
 Brandon Philips <brandon@ifup.org>
 Brendan Long <self@brendanlong.com>
+Brian R. Becker <brbecker@gmail.com>
 Caleb Callaway <enlightened.despot@gmail.com>
 Carsten Hagemann <moter8@gmail.com>
 Cathryne Linenweaver <cathryne.linenweaver@gmail.com> <Cathryne@users.noreply.github.com>
 Chris Howie <me@chrishowie.com>
 Chris Joel <chris@scriptolo.gy>
 Colin Kennedy <moshen.colin@gmail.com>
+Daniel Bergmann <dan.arne.bergmann@gmail.com> <brgmnn@users.noreply.github.com>
 Daniel Martí <mvdan@mvdan.cc>
+Denis A. <denisva@gmail.com>
 Dennis Wilson <dw@risu.io>
 Dominik Heidler <dominik@heidler.eu>
 Elias Jarlebring <jarlebring@gmail.com>
 Emil Hessman <emil@hessman.se>
+Erik Meitner <e.meitner@willystreet.coop>
 Federico Castagnini <federico.castagnini@gmail.com>
 Felix Ableitner <me@nutomic.com>
 Felix Unterpaintner <bigbear2nd@gmail.com>
 Francois-Xavier Gsell <fxgsell@gmail.com>
+Frank Isemann <frank@isemann.name>
 Gilli Sigurdsson <gilli@vx.is>
+Jacek Szafarkiewicz <szafar@linux.pl>
 Jakob Borg <jakob@nym.se>
 James Patterson <jamespatterson@operamail.com> <jpjp@users.noreply.github.com>
 Jaroslav Malec <dzardacz@gmail.com>
@@ -37,9 +44,9 @@ Karol Różycki <rozycki.karol@gmail.com>
 Ken'ichi Kamada <kamada@nanohz.org>
 Lode Hoste <zillode@zillode.be>
 Lord Landon Agahnim <lordlandon@gmail.com>
-Marcin Dziadus <dziadus.marcin@gmail.com>
 Marc Laporte <marc@marclaporte.com> <marc@laporte.name>
 Marc Pujol <kilburn@la3.org>
+Marcin Dziadus <dziadus.marcin@gmail.com>
 Michael Jephcote <rewt0r@gmx.com> <Rewt0r@users.noreply.github.com>
 Michael Tilli <pyfisch@gmail.com>
 Pascal Jungblut <github@pascalj.com> <mail@pascal-jungblut.com>
@@ -1,13 +1,17 @@
 {
 	"ImportPath": "github.com/syncthing/syncthing",
-	"GoVersion": "go1.4",
+	"GoVersion": "go1.5rc1",
 	"Packages": [
 		"./cmd/..."
 	],
 	"Deps": [
 		{
 			"ImportPath": "github.com/bkaradzic/go-lz4",
-			"Rev": "93a831dcee242be64a9cc9803dda84af25932de7"
+			"Rev": "d47913b1412890a261b9fefae99d72d2bf5aebd8"
+		},
+		{
+			"ImportPath": "github.com/calmh/du",
+			"Rev": "3c0690cca16228b97741327b1b6781397afbdb24"
 		},
 		{
 			"ImportPath": "github.com/calmh/logger",
@@ -21,29 +25,29 @@
 			"ImportPath": "github.com/calmh/xdr",
 			"Rev": "5f7208e86762911861c94f1849eddbfc0a60cbf0"
 		},
+		{
+			"ImportPath": "github.com/golang/snappy",
+			"Rev": "723cc1e459b8eea2dea4583200fd60757d40097a"
+		},
 		{
 			"ImportPath": "github.com/juju/ratelimit",
-			"Rev": "c5abe513796336ee2869745bff0638508450e9c5"
+			"Rev": "772f5c38e468398c4511514f4f6aa9a4185bc0a0"
 		},
 		{
 			"ImportPath": "github.com/kardianos/osext",
-			"Rev": "efacde03154693404c65e7aa7d461ac9014acd0c"
+			"Rev": "6e7f843663477789fac7c02def0d0909e969b4e5"
 		},
 		{
 			"ImportPath": "github.com/syncthing/protocol",
-			"Rev": "e7db2648034fb71b051902a02bc25d4468ed492e"
+			"Rev": "388a29bbe21d8772ee4c29f4520aa8040309607d"
 		},
 		{
 			"ImportPath": "github.com/syndtr/goleveldb/leveldb",
-			"Rev": "87e4e645d80ae9c537e8f2dee52b28036a5dd75e"
-		},
-		{
-			"ImportPath": "github.com/syndtr/gosnappy/snappy",
-			"Rev": "156a073208e131d7d2e212cb749feae7c339e846"
+			"Rev": "b743d92d3215f11c9b5ce8830fafe1f16786adf4"
 		},
 		{
 			"ImportPath": "github.com/thejerf/suture",
-			"Rev": "ff19fb384c3fe30f42717967eaa69da91e5f317c"
+			"Rev": "fc7aaeabdc43fe41c5328efa1479ffea0b820978"
 		},
 		{
 			"ImportPath": "github.com/vitrun/qart/coding",
@@ -59,19 +63,19 @@
 		},
 		{
 			"ImportPath": "golang.org/x/crypto/bcrypt",
-			"Rev": "c57d4a71915a248dbad846d60825145062b4c18e"
+			"Rev": "c16968172724c0b5e8bdc6ad33f5a79443a44cd7"
 		},
 		{
 			"ImportPath": "golang.org/x/crypto/blowfish",
-			"Rev": "c57d4a71915a248dbad846d60825145062b4c18e"
+			"Rev": "c16968172724c0b5e8bdc6ad33f5a79443a44cd7"
 		},
 		{
 			"ImportPath": "golang.org/x/text/transform",
-			"Rev": "2076e9cab4147459c82bc81169e46c139d358547"
+			"Rev": "723492b65e225eafcba054e76ba18bb9c5ac1ea2"
 		},
 		{
 			"ImportPath": "golang.org/x/text/unicode/norm",
-			"Rev": "2076e9cab4147459c82bc81169e46c139d358547"
+			"Rev": "723492b65e225eafcba054e76ba18bb9c5ac1ea2"
 		}
 	]
 }
@@ -4,4 +4,5 @@ go:
  - 1.1
  - 1.2
  - 1.3
+  - 1.4
  - tip
@@ -4,7 +4,7 @@ go-lz4
 go-lz4 is port of LZ4 lossless compression algorithm to Go. The original C code
 is located at:

-https://code.google.com/p/lz4/
+https://github.com/Cyan4973/lz4

 Status
 ------
@@ -0,0 +1,23 @@
+// +build gofuzz
+
+package lz4
+
+import "encoding/binary"
+
+func Fuzz(data []byte) int {
+
+	if len(data) < 4 {
+		return 0
+	}
+
+	ln := binary.LittleEndian.Uint32(data)
+	if ln > (1 << 21) {
+		return 0
+	}
+
+	if _, err := Decode(nil, data); err != nil {
+		return 0
+	}
+
+	return 1
+}
@@ -141,7 +141,7 @@ func Decode(dst, src []byte) ([]byte, error) {
 			length += ln
 		}

-		if int(d.spos+length) > len(d.src) {
+		if int(d.spos+length) > len(d.src) || int(d.dpos+length) > len(d.dst) {
 			return nil, ErrCorrupt
 		}

@@ -179,7 +179,12 @@ func Decode(dst, src []byte) ([]byte, error) {
 		}

 		literal := d.dpos - d.ref
+
 		if literal < 4 {
+			if int(d.dpos+4) > len(d.dst) {
+				return nil, ErrCorrupt
+			}
+
 			d.cp(4, decr[literal])
 		} else {
 			length += 4
@@ -25,8 +25,10 @@

 package lz4

-import "encoding/binary"
-import "errors"
+import (
+	"encoding/binary"
+	"errors"
+)

 const (
 	minMatch              = 4
@@ -0,0 +1,24 @@
+This is free and unencumbered software released into the public domain.
+
+Anyone is free to copy, modify, publish, use, compile, sell, or
+distribute this software, either in source code form or as a compiled
+binary, for any purpose, commercial or non-commercial, and by any
+means.
+
+In jurisdictions that recognize copyright laws, the author or authors
+of this software dedicate any and all copyright interest in the
+software to the public domain. We make this dedication for the benefit
+of the public at large and to the detriment of our heirs and
+successors. We intend this dedication to be an overt act of
+relinquishment in perpetuity of all present and future rights to this
+software under copyright law.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
+
+For more information, please refer to <http://unlicense.org>
@@ -0,0 +1,14 @@
+du
+==
+
+Get total and available disk space on a given volume.
+
+Documentation
+-------------
+
+http://godoc.org/github.com/calmh/du
+
+License
+-------
+
+Public Domain
@@ -0,0 +1,21 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+
+	"github.com/calmh/du"
+)
+
+var KB = int64(1024)
+
+func main() {
+	usage, err := du.Get(os.Args[1])
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println("Free:", usage.FreeBytes/(KB*KB), "MiB")
+	fmt.Println("Available:", usage.AvailBytes/(KB*KB), "MiB")
+	fmt.Println("Size:", usage.TotalBytes/(KB*KB), "MiB")
+}
@@ -0,0 +1,8 @@
+package du
+
+// Usage holds information about total and available storage on a volume.
+type Usage struct {
+	TotalBytes int64 // Size of volume
+	FreeBytes  int64 // Unused size
+	AvailBytes int64 // Available to a non-privileged user
+}
@@ -0,0 +1,24 @@
+// +build !windows,!netbsd,!openbsd,!solaris
+
+package du
+
+import (
+	"path/filepath"
+	"syscall"
+)
+
+// Get returns the Usage of a given path, or an error if usage data is
+// unavailable.
+func Get(path string) (Usage, error) {
+	var stat syscall.Statfs_t
+	err := syscall.Statfs(filepath.Clean(path), &stat)
+	if err != nil {
+		return Usage{}, err
+	}
+	u := Usage{
+		FreeBytes:  int64(stat.Bfree) * int64(stat.Bsize),
+		TotalBytes: int64(stat.Blocks) * int64(stat.Bsize),
+		AvailBytes: int64(stat.Bavail) * int64(stat.Bsize),
+	}
+	return u, nil
+}
@@ -0,0 +1,13 @@
+// +build netbsd openbsd solaris
+
+package du
+
+import "errors"
+
+var ErrUnsupported = errors.New("unsupported platform")
+
+// Get returns the Usage of a given path, or an error if usage data is
+// unavailable.
+func Get(path string) (Usage, error) {
+	return Usage{}, ErrUnsupported
+}
@@ -0,0 +1,27 @@
+package du
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+// Get returns the Usage of a given path, or an error if usage data is
+// unavailable.
+func Get(path string) (Usage, error) {
+	h := syscall.MustLoadDLL("kernel32.dll")
+	c := h.MustFindProc("GetDiskFreeSpaceExW")
+
+	var u Usage
+
+	ret, _, err := c.Call(
+		uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(path))),
+		uintptr(unsafe.Pointer(&u.FreeBytes)),
+		uintptr(unsafe.Pointer(&u.TotalBytes)),
+		uintptr(unsafe.Pointer(&u.AvailBytes)))
+
+	if ret == 0 {
+		return u, err
+	}
+
+	return u, nil
+}
@@ -0,0 +1,14 @@
+# This is the official list of Snappy-Go authors for copyright purposes.
+# This file is distinct from the CONTRIBUTORS files.
+# See the latter for an explanation.
+
+# Names should be added to this file as
+#	Name or Organization <email address>
+# The email address is not required for organizations.
+
+# Please keep the list sorted.
+
+Damian Gryski <dgryski@gmail.com>
+Google Inc.
+Jan Mercl <0xjnml@gmail.com>
+Sebastien Binet <seb.binet@gmail.com>
@@ -0,0 +1,36 @@
+# This is the official list of people who can contribute
+# (and typically have contributed) code to the Snappy-Go repository.
+# The AUTHORS file lists the copyright holders; this file
+# lists people.  For example, Google employees are listed here
+# but not in AUTHORS, because Google holds the copyright.
+#
+# The submission process automatically checks to make sure
+# that people submitting code are listed in this file (by email address).
+#
+# Names should be added to this file only after verifying that
+# the individual or the individual's organization has agreed to
+# the appropriate Contributor License Agreement, found here:
+#
+#     http://code.google.com/legal/individual-cla-v1.0.html
+#     http://code.google.com/legal/corporate-cla-v1.0.html
+#
+# The agreement for individuals can be filled out on the web.
+#
+# When adding J Random Contributor's name to this file,
+# either J's name or J's organization's name should be
+# added to the AUTHORS file, depending on whether the
+# individual or corporate CLA was used.
+
+# Names should be added to this file like so:
+#     Name <email address>
+
+# Please keep the list sorted.
+
+Damian Gryski <dgryski@gmail.com>
+Jan Mercl <0xjnml@gmail.com>
+Kai Backman <kaib@golang.org>
+Marc-Antoine Ruel <maruel@chromium.org>
+Nigel Tao <nigeltao@golang.org>
+Rob Pike <r@golang.org>
+Russ Cox <rsc@golang.org>
+Sebastien Binet <seb.binet@gmail.com>
@@ -0,0 +1,27 @@
+Copyright (c) 2011 The Snappy-Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
@@ -0,0 +1,7 @@
+The Snappy compression format in the Go programming language.
+
+To download and install from source:
+$ go get github.com/golang/snappy
+
+Unless otherwise noted, the Snappy-Go source files are distributed
+under the BSD-style license found in the LICENSE file.
@@ -13,6 +13,8 @@ import (
 var (
 	// ErrCorrupt reports that the input is invalid.
 	ErrCorrupt = errors.New("snappy: corrupt input")
+	// ErrTooLarge reports that the uncompressed length is too large.
+	ErrTooLarge = errors.New("snappy: decoded block is too large")
 	// ErrUnsupported reports that the input isn't supported.
 	ErrUnsupported = errors.New("snappy: unsupported input")
 )
@@ -27,11 +29,13 @@ func DecodedLen(src []byte) (int, error) {
 // that the length header occupied.
 func decodedLen(src []byte) (blockLen, headerLen int, err error) {
 	v, n := binary.Uvarint(src)
-	if n == 0 {
+	if n <= 0 || v > 0xffffffff {
 		return 0, 0, ErrCorrupt
 	}
-	if uint64(int(v)) != v {
-		return 0, 0, errors.New("snappy: decoded block is too large")
+
+	const wordSize = 32 << (^uint(0) >> 32 & 1)
+	if wordSize == 32 && v > 0x7fffffff {
+		return 0, 0, ErrTooLarge
 	}
 	return int(v), n, nil
 }
@@ -56,7 +60,7 @@ func Decode(dst, src []byte) ([]byte, error) {
 			x := uint(src[s] >> 2)
 			switch {
 			case x < 60:
-				s += 1
+				s++
 			case x == 60:
 				s += 2
 				if s > len(src) {
@@ -130,7 +134,7 @@ func Decode(dst, src []byte) ([]byte, error) {

 // NewReader returns a new Reader that decompresses from r, using the framing
 // format described at
-// https://code.google.com/p/snappy/source/browse/trunk/framing_format.txt
+// https://github.com/google/snappy/blob/master/framing_format.txt
 func NewReader(r io.Reader) *Reader {
 	return &Reader{
 		r:       r,
@@ -200,7 +204,7 @@ func (r *Reader) Read(p []byte) (int, error) {
 		}

 		// The chunk types are specified at
-		// https://code.google.com/p/snappy/source/browse/trunk/framing_format.txt
+		// https://github.com/google/snappy/blob/master/framing_format.txt
 		switch chunkType {
 		case chunkTypeCompressedData:
 			// Section 4.2. Compressed data (chunk type 0x00).
@@ -280,13 +284,11 @@ func (r *Reader) Read(p []byte) (int, error) {
 			// Section 4.5. Reserved unskippable chunks (chunk types 0x02-0x7f).
 			r.err = ErrUnsupported
 			return 0, r.err
-
-		} else {
-			// Section 4.4 Padding (chunk type 0xfe).
-			// Section 4.6. Reserved skippable chunks (chunk types 0x80-0xfd).
-			if !r.readFull(r.buf[:chunkLen]) {
-				return 0, r.err
-			}
+		}
+		// Section 4.4 Padding (chunk type 0xfe).
+		// Section 4.6. Reserved skippable chunks (chunk types 0x80-0xfd).
+		if !r.readFull(r.buf[:chunkLen]) {
+			return 0, r.err
 		}
 	}
 }
@@ -79,7 +79,7 @@ func emitCopy(dst []byte, offset, length int) int {
 // slice of dst if dst was large enough to hold the entire encoded block.
 // Otherwise, a newly allocated slice will be returned.
 // It is valid to pass a nil dst.
-func Encode(dst, src []byte) ([]byte, error) {
+func Encode(dst, src []byte) []byte {
 	if n := MaxEncodedLen(len(src)); len(dst) < n {
 		dst = make([]byte, n)
 	}
@@ -92,7 +92,7 @@ func Encode(dst, src []byte) ([]byte, error) {
 		if len(src) != 0 {
 			d += emitLiteral(dst[d:], src)
 		}
-		return dst[:d], nil
+		return dst[:d]
 	}

 	// Initialize the hash table. Its size ranges from 1<<8 to 1<<14 inclusive.
@@ -145,7 +145,7 @@ func Encode(dst, src []byte) ([]byte, error) {
 	if lit != len(src) {
 		d += emitLiteral(dst[d:], src[lit:])
 	}
-	return dst[:d], nil
+	return dst[:d]
 }

 // MaxEncodedLen returns the maximum length of a snappy block, given its
@@ -176,7 +176,7 @@ func MaxEncodedLen(srcLen int) int {

 // NewWriter returns a new Writer that compresses to w, using the framing
 // format described at
-// https://code.google.com/p/snappy/source/browse/trunk/framing_format.txt
+// https://github.com/google/snappy/blob/master/framing_format.txt
 func NewWriter(w io.Writer) *Writer {
 	return &Writer{
 		w:   w,
@@ -226,11 +226,7 @@ func (w *Writer) Write(p []byte) (n int, errRet error) {
 		// Compress the buffer, discarding the result if the improvement
 		// isn't at least 12.5%.
 		chunkType := uint8(chunkTypeCompressedData)
-		chunkBody, err := Encode(w.enc, uncompressed)
-		if err != nil {
-			w.err = err
-			return n, err
-		}
+		chunkBody := Encode(w.enc, uncompressed)
 		if len(chunkBody) >= len(uncompressed)-len(uncompressed)/8 {
 			chunkType, chunkBody = chunkTypeUncompressedData, uncompressed
 		}
@@ -244,11 +240,11 @@ func (w *Writer) Write(p []byte) (n int, errRet error) {
 		w.buf[5] = uint8(checksum >> 8)
 		w.buf[6] = uint8(checksum >> 16)
 		w.buf[7] = uint8(checksum >> 24)
-		if _, err = w.w.Write(w.buf[:]); err != nil {
+		if _, err := w.w.Write(w.buf[:]); err != nil {
 			w.err = err
 			return n, err
 		}
-		if _, err = w.w.Write(chunkBody); err != nil {
+		if _, err := w.w.Write(chunkBody); err != nil {
 			w.err = err
 			return n, err
 		}
@@ -5,7 +5,7 @@
 // Package snappy implements the snappy block-based compression format.
 // It aims for very high speeds and reasonable compression.
 //
-// The C++ snappy implementation is at http://code.google.com/p/snappy/
+// The C++ snappy implementation is at https://github.com/google/snappy
 package snappy

 import (
@@ -46,7 +46,7 @@ const (
 	chunkHeaderSize = 4
 	magicChunk      = "\xff\x06\x00\x00" + magicBody
 	magicBody       = "sNaPpY"
-	// https://code.google.com/p/snappy/source/browse/trunk/framing_format.txt says
+	// https://github.com/google/snappy/blob/master/framing_format.txt says
 	// that "the uncompressed data in a chunk must be no longer than 65536 bytes".
 	maxUncompressedChunkLen = 65536
 )
@@ -61,7 +61,7 @@ const (
 var crcTable = crc32.MakeTable(crc32.Castagnoli)

 // crc implements the checksum specified in section 3 of
-// https://code.google.com/p/snappy/source/browse/trunk/framing_format.txt
+// https://github.com/google/snappy/blob/master/framing_format.txt
 func crc(b []byte) uint32 {
 	c := crc32.Update(0, crcTable, b)
 	return uint32(c>>15|c<<17) + 0xa282ead8
@@ -24,11 +24,7 @@ var (
 )

 func roundtrip(b, ebuf, dbuf []byte) error {
-	e, err := Encode(ebuf, b)
-	if err != nil {
-		return fmt.Errorf("encoding error: %v", err)
-	}
-	d, err := Decode(dbuf, e)
+	d, err := Decode(dbuf, Encode(ebuf, b))
 	if err != nil {
 		return fmt.Errorf("decoding error: %v", err)
 	}
@@ -82,6 +78,26 @@ func TestSmallRegular(t *testing.T) {
 	}
 }

+func TestInvalidVarint(t *testing.T) {
+	data := []byte("\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\x00")
+	if _, err := DecodedLen(data); err != ErrCorrupt {
+		t.Errorf("DecodedLen: got %v, want ErrCorrupt", err)
+	}
+	if _, err := Decode(nil, data); err != ErrCorrupt {
+		t.Errorf("Decode: got %v, want ErrCorrupt", err)
+	}
+
+	// The encoded varint overflows 32 bits
+	data = []byte("\xff\xff\xff\xff\xff\x00")
+
+	if _, err := DecodedLen(data); err != ErrCorrupt {
+		t.Errorf("DecodedLen: got %v, want ErrCorrupt", err)
+	}
+	if _, err := Decode(nil, data); err != ErrCorrupt {
+		t.Errorf("Decode: got %v, want ErrCorrupt", err)
+	}
+}
+
 func cmp(a, b []byte) error {
 	if len(a) != len(b) {
 		return fmt.Errorf("got %d bytes, want %d", len(a), len(b))
@@ -197,10 +213,7 @@ func TestWriterReset(t *testing.T) {
 }

 func benchDecode(b *testing.B, src []byte) {
-	encoded, err := Encode(nil, src)
-	if err != nil {
-		b.Fatal(err)
-	}
+	encoded := Encode(nil, src)
 	// Bandwidth is in amount of uncompressed data.
 	b.SetBytes(int64(len(src)))
 	b.ResetTimer()
@@ -222,7 +235,7 @@ func benchEncode(b *testing.B, src []byte) {
 func readFile(b testing.TB, filename string) []byte {
 	src, err := ioutil.ReadFile(filename)
 	if err != nil {
-		b.Fatalf("failed reading %s: %s", filename, err)
+		b.Skipf("skipping benchmark: %v", err)
 	}
 	if len(src) == 0 {
 		b.Fatalf("%s has zero length", filename)
@@ -284,14 +297,14 @@ var testFiles = []struct {
 // The test data files are present at this canonical URL.
 const baseURL = "https://raw.githubusercontent.com/google/snappy/master/testdata/"

-func downloadTestdata(basename string) (errRet error) {
+func downloadTestdata(b *testing.B, basename string) (errRet error) {
 	filename := filepath.Join(*testdata, basename)
 	if stat, err := os.Stat(filename); err == nil && stat.Size() != 0 {
 		return nil
 	}

 	if !*download {
-		return fmt.Errorf("test data not found; skipping benchmark without the -download flag")
+		b.Skipf("test data not found; skipping benchmark without the -download flag")
 	}
 	// Download the official snappy C++ implementation reference test data
 	// files for benchmarking.
@@ -326,7 +339,7 @@ func downloadTestdata(basename string) (errRet error) {
 }

 func benchFile(b *testing.B, n int, decode bool) {
-	if err := downloadTestdata(testFiles[n].filename); err != nil {
+	if err := downloadTestdata(b, testFiles[n].filename); err != nil {
 		b.Fatalf("failed to download testdata: %s", err)
 	}
 	data := readFile(b, filepath.Join(*testdata, testFiles[n].filename))
@@ -1,5 +1,8 @@
-This package contains an efficient token-bucket-based rate limiter.
-Copyright (C) 2015 Canonical Ltd.
+All files in this repository are licensed as follows. If you contribute
+to this repository, it is assumed that you license your contribution
+under the same license unless you state otherwise.
+
+All files Copyright (C) 2015 Canonical Ltd. unless otherwise specified in the file.

 This software is licensed under the LGPLv3, included below.

@@ -20,7 +20,7 @@ token in the bucket represents one byte.
 ```go
 func Writer(w io.Writer, bucket *Bucket) io.Writer
 ```
-Writer returns a reader that is rate limited by the given token bucket. Each
+Writer returns a writer that is rate limited by the given token bucket. Each
 token in the bucket represents one byte.

 #### type Bucket
@@ -2,7 +2,8 @@
 // Licensed under the LGPLv3 with static-linking exception.
 // See LICENCE file for details.

-// The ratelimit package provides an efficient token bucket implementation.
+// The ratelimit package provides an efficient token bucket implementation
+// that can be used to limit the rate of arbitrary things.
 // See http://en.wikipedia.org/wiki/Token_bucket.
 package ratelimit

@@ -10,6 +11,7 @@ import (
 	"strconv"
 	"sync"
 	"time"
+	"math"
 )

 // Bucket represents a token bucket that fills at a predetermined rate.
@@ -55,7 +57,7 @@ func NewBucketWithRate(rate float64, capacity int64) *Bucket {
 			continue
 		}
 		tb := NewBucketWithQuantum(fillInterval, capacity, quantum)
-		if diff := abs(tb.Rate() - rate); diff/rate <= rateMargin {
+		if diff := math.Abs(tb.Rate() - rate); diff/rate <= rateMargin {
 			return tb
 		}
 	}
@@ -217,10 +219,3 @@ func (tb *Bucket) adjust(now time.Time) (currentTick int64) {
 	tb.availTick = currentTick
 	return
 }
-
-func abs(f float64) float64 {
-	if f < 0 {
-		return -f
-	}
-	return f
-}
@@ -4,7 +4,9 @@

 There is sometimes utility in finding the current executable file
 that is running. This can be used for upgrading the current executable
-or finding resources located relative to the executable file.
+or finding resources located relative to the executable file. Both
+working directory and the os.Args[0] value are arbitrary and cannot
+be relied on; os.Args[0] can be "faked".

 Multi-platform and supports:
 * Linux
@@ -16,12 +16,12 @@ func Executable() (string, error) {
 }

 // Returns same path as Executable, returns just the folder
-// path. Excludes the executable name.
+// path. Excludes the executable name and any trailing slash.
 func ExecutableFolder() (string, error) {
 	p, err := Executable()
 	if err != nil {
 		return "", err
 	}
-	folder, _ := filepath.Split(p)
-	return folder, nil
+
+	return filepath.Dir(p), nil
 }
@@ -17,12 +17,14 @@ import (
 func executable() (string, error) {
 	switch runtime.GOOS {
 	case "linux":
-		const deletedSuffix = " (deleted)"
+		const deletedTag = " (deleted)"
 		execpath, err := os.Readlink("/proc/self/exe")
 		if err != nil {
 			return execpath, err
 		}
-		return strings.TrimSuffix(execpath, deletedSuffix), nil
+		execpath = strings.TrimSuffix(execpath, deletedTag)
+		execpath = strings.TrimPrefix(execpath, deletedTag)
+		return execpath, nil
 	case "netbsd":
 		return os.Readlink("/proc/curproc/exe")
 	case "openbsd", "dragonfly":
@@ -24,6 +24,29 @@ const (
 	executableEnvValueDelete = "delete"
 )

+func TestPrintExecutable(t *testing.T) {
+	ef, err := Executable()
+	if err != nil {
+		t.Fatalf("Executable failed: %v", err)
+	}
+	t.Log("Executable:", ef)
+}
+func TestPrintExecutableFolder(t *testing.T) {
+	ef, err := ExecutableFolder()
+	if err != nil {
+		t.Fatalf("ExecutableFolder failed: %v", err)
+	}
+	t.Log("Executable Folder:", ef)
+}
+func TestExecutableFolder(t *testing.T) {
+	ef, err := ExecutableFolder()
+	if err != nil {
+		t.Fatalf("ExecutableFolder failed: %v", err)
+	}
+	if ef[len(ef)-1] == filepath.Separator {
+		t.Fatal("ExecutableFolder ends with a trailing slash.")
+	}
+}
 func TestExecutableMatch(t *testing.T) {
 	ep, err := Executable()
 	if err != nil {
@@ -31,15 +31,16 @@ func (t *TestModel) Index(deviceID DeviceID, folder string, files []FileInfo, fl
 func (t *TestModel) IndexUpdate(deviceID DeviceID, folder string, files []FileInfo, flags uint32, options []Option) {
 }

-func (t *TestModel) Request(deviceID DeviceID, folder, name string, offset int64, size int, hash []byte, flags uint32, options []Option) ([]byte, error) {
+func (t *TestModel) Request(deviceID DeviceID, folder, name string, offset int64, hash []byte, flags uint32, options []Option, buf []byte) error {
 	t.folder = folder
 	t.name = name
 	t.offset = offset
-	t.size = size
+	t.size = len(buf)
 	t.hash = hash
 	t.flags = flags
 	t.options = options
-	return t.data, nil
+	copy(buf, t.data)
+	return nil
 }

 func (t *TestModel) Close(deviceID DeviceID, err error) {
@@ -0,0 +1,23 @@
+// Copyright (C) 2015 The Protocol Authors.
+
+package protocol
+
+import "testing"
+
+func TestWinsConflict(t *testing.T) {
+	testcases := [][2]FileInfo{
+		// The first should always win over the second
+		{{Modified: 42}, {Modified: 41}},
+		{{Modified: 41}, {Modified: 42, Flags: FlagDeleted}},
+		{{Modified: 41, Version: Vector{{42, 2}, {43, 1}}}, {Modified: 41, Version: Vector{{42, 1}, {43, 2}}}},
+	}
+
+	for _, tc := range testcases {
+		if !tc[0].WinsConflict(tc[1]) {
+			t.Errorf("%v should win over %v", tc[0], tc[1])
+		}
+		if tc[1].WinsConflict(tc[0]) {
+			t.Errorf("%v should not win over %v", tc[1], tc[0])
+		}
+	}
+}
@@ -0,0 +1,70 @@
+// Copyright (C) 2015 The Protocol Authors.
+
+// +build gofuzz
+
+package protocol
+
+import (
+	"bytes"
+	"encoding/binary"
+	"encoding/hex"
+	"fmt"
+	"reflect"
+	"sync"
+)
+
+func Fuzz(data []byte) int {
+	// Regenerate the length, or we'll most commonly exit quickly due to an
+	// unexpected eof which is unintestering.
+	if len(data) > 8 {
+		binary.BigEndian.PutUint32(data[4:], uint32(len(data))-8)
+	}
+
+	// Setup a rawConnection we'll use to parse the message.
+	c := rawConnection{
+		cr:     &countingReader{Reader: bytes.NewReader(data)},
+		closed: make(chan struct{}),
+		pool: sync.Pool{
+			New: func() interface{} {
+				return make([]byte, BlockSize)
+			},
+		},
+	}
+
+	// Attempt to parse the message.
+	hdr, msg, err := c.readMessage()
+	if err != nil {
+		return 0
+	}
+
+	// If parsing worked, attempt to encode it again.
+	newBs, err := msg.AppendXDR(nil)
+	if err != nil {
+		panic("not encodable")
+	}
+
+	// Create an appriate header for the re-encoding.
+	newMsg := make([]byte, 8)
+	binary.BigEndian.PutUint32(newMsg, encodeHeader(hdr))
+	binary.BigEndian.PutUint32(newMsg[4:], uint32(len(newBs)))
+	newMsg = append(newMsg, newBs...)
+
+	// Use the rawConnection to parse the re-encoding.
+	c.cr = &countingReader{Reader: bytes.NewReader(newMsg)}
+	hdr2, msg2, err := c.readMessage()
+	if err != nil {
+		fmt.Println("Initial:\n" + hex.Dump(data))
+		fmt.Println("New:\n" + hex.Dump(newMsg))
+		panic("not parseable after re-encode: " + err.Error())
+	}
+
+	// Make sure the data is the same as it was before.
+	if hdr != hdr2 {
+		panic("headers differ")
+	}
+	if !reflect.DeepEqual(msg, msg2) {
+		panic("contents differ")
+	}
+
+	return 1
+}
@@ -0,0 +1,89 @@
+// Copyright (C) 2015 The Protocol Authors.
+
+// +build gofuzz
+
+package protocol
+
+import (
+	"encoding/binary"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"strings"
+	"testing"
+	"testing/quick"
+)
+
+// This can be used to generate a corpus of valid messages as a starting point
+// for the fuzzer.
+func TestGenerateCorpus(t *testing.T) {
+	t.Skip("Use to generate initial corpus only")
+
+	n := 0
+	check := func(idx IndexMessage) bool {
+		for i := range idx.Options {
+			if len(idx.Options[i].Key) > 64 {
+				idx.Options[i].Key = idx.Options[i].Key[:64]
+			}
+		}
+		hdr := header{
+			version:     0,
+			msgID:       42,
+			msgType:     messageTypeIndex,
+			compression: false,
+		}
+
+		msgBs := idx.MustMarshalXDR()
+
+		buf := make([]byte, 8)
+		binary.BigEndian.PutUint32(buf, encodeHeader(hdr))
+		binary.BigEndian.PutUint32(buf[4:], uint32(len(msgBs)))
+		buf = append(buf, msgBs...)
+
+		ioutil.WriteFile(fmt.Sprintf("testdata/corpus/test-%03d.xdr", n), buf, 0644)
+		n++
+		return true
+	}
+
+	if err := quick.Check(check, &quick.Config{MaxCount: 1000}); err != nil {
+		t.Fatal(err)
+	}
+}
+
+// Tests any crashers found by the fuzzer, for closer investigation.
+func TestCrashers(t *testing.T) {
+	testFiles(t, "testdata/crashers")
+}
+
+// Tests the entire corpus, which should PASS before the fuzzer starts
+// fuzzing.
+func TestCorpus(t *testing.T) {
+	testFiles(t, "testdata/corpus")
+}
+
+func testFiles(t *testing.T, dir string) {
+	fd, err := os.Open(dir)
+	if err != nil {
+		t.Fatal(err)
+	}
+	crashers, err := fd.Readdirnames(-1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, name := range crashers {
+		if strings.HasSuffix(name, ".output") {
+			continue
+		}
+		if strings.HasSuffix(name, ".quoted") {
+			continue
+		}
+
+		t.Log(name)
+		crasher, err := ioutil.ReadFile(dir + "/" + name)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		Fuzz(crasher)
+	}
+}
@@ -9,7 +9,7 @@ import "fmt"

 type IndexMessage struct {
 	Folder  string
-	Files   []FileInfo
+	Files   []FileInfo // max:1000000
 	Flags   uint32
 	Options []Option // max:64
 }
@@ -20,7 +20,7 @@ type FileInfo struct {
 	Modified     int64
 	Version      Vector
 	LocalVersion int64
-	Blocks       []BlockInfo
+	Blocks       []BlockInfo // max:1000000
 }

 func (f FileInfo) String() string {
@@ -58,6 +58,31 @@ func (f FileInfo) HasPermissionBits() bool {
 	return f.Flags&FlagNoPermBits == 0
 }

+// WinsConflict returns true if "f" is the one to choose when it is in
+// conflict with "other".
+func (f FileInfo) WinsConflict(other FileInfo) bool {
+	// If a modification is in conflict with a delete, we pick the
+	// modification.
+	if !f.IsDeleted() && other.IsDeleted() {
+		return true
+	}
+	if f.IsDeleted() && !other.IsDeleted() {
+		return false
+	}
+
+	// The one with the newer modification time wins.
+	if f.Modified > other.Modified {
+		return true
+	}
+	if f.Modified < other.Modified {
+		return false
+	}
+
+	// The modification times were equal. Use the device ID in the version
+	// vector as tie breaker.
+	return f.Version.Compare(other.Version) == ConcurrentGreater
+}
+
 type BlockInfo struct {
 	Offset int64 // noencode (cache only)
 	Size   int32
@@ -84,9 +109,9 @@ type ResponseMessage struct {
 }

 type ClusterConfigMessage struct {
-	ClientName    string // max:64
-	ClientVersion string // max:64
-	Folders       []Folder
+	ClientName    string   // max:64
+	ClientVersion string   // max:64
+	Folders       []Folder // max:1000000
 	Options       []Option // max:64
 }

@@ -100,8 +125,8 @@ func (o *ClusterConfigMessage) GetOption(key string) string {
 }

 type Folder struct {
-	ID      string // max:64
-	Devices []Device
+	ID      string   // max:64
+	Devices []Device // max:1000000
 	Flags   uint32
 	Options []Option // max:64
 }
@@ -42,7 +42,7 @@ IndexMessage Structure:

 struct IndexMessage {
 	string Folder<>;
-	FileInfo Files<>;
+	FileInfo Files<1000000>;
 	unsigned int Flags;
 	Option Options<64>;
 }
@@ -75,6 +75,9 @@ func (o IndexMessage) AppendXDR(bs []byte) ([]byte, error) {

 func (o IndexMessage) EncodeXDRInto(xw *xdr.Writer) (int, error) {
 	xw.WriteString(o.Folder)
+	if l := len(o.Files); l > 1000000 {
+		return xw.Tot(), xdr.ElementSizeExceeded("Files", l, 1000000)
+	}
 	xw.WriteUint32(uint32(len(o.Files)))
 	for i := range o.Files {
 		_, err := o.Files[i].EncodeXDRInto(xw)
@@ -111,7 +114,10 @@ func (o *IndexMessage) DecodeXDRFrom(xr *xdr.Reader) error {
 	o.Folder = xr.ReadString()
 	_FilesSize := int(xr.ReadUint32())
 	if _FilesSize < 0 {
-		return xdr.ElementSizeExceeded("Files", _FilesSize, 0)
+		return xdr.ElementSizeExceeded("Files", _FilesSize, 1000000)
+	}
+	if _FilesSize > 1000000 {
+		return xdr.ElementSizeExceeded("Files", _FilesSize, 1000000)
 	}
 	o.Files = make([]FileInfo, _FilesSize)
 	for i := range o.Files {
@@ -173,7 +179,7 @@ struct FileInfo {
 	hyper Modified;
 	Vector Version;
 	hyper LocalVersion;
-	BlockInfo Blocks<>;
+	BlockInfo Blocks<1000000>;
 }

 */
@@ -214,6 +220,9 @@ func (o FileInfo) EncodeXDRInto(xw *xdr.Writer) (int, error) {
 		return xw.Tot(), err
 	}
 	xw.WriteUint64(uint64(o.LocalVersion))
+	if l := len(o.Blocks); l > 1000000 {
+		return xw.Tot(), xdr.ElementSizeExceeded("Blocks", l, 1000000)
+	}
 	xw.WriteUint32(uint32(len(o.Blocks)))
 	for i := range o.Blocks {
 		_, err := o.Blocks[i].EncodeXDRInto(xw)
@@ -243,7 +252,10 @@ func (o *FileInfo) DecodeXDRFrom(xr *xdr.Reader) error {
 	o.LocalVersion = int64(xr.ReadUint64())
 	_BlocksSize := int(xr.ReadUint32())
 	if _BlocksSize < 0 {
-		return xdr.ElementSizeExceeded("Blocks", _BlocksSize, 0)
+		return xdr.ElementSizeExceeded("Blocks", _BlocksSize, 1000000)
+	}
+	if _BlocksSize > 1000000 {
+		return xdr.ElementSizeExceeded("Blocks", _BlocksSize, 1000000)
 	}
 	o.Blocks = make([]BlockInfo, _BlocksSize)
 	for i := range o.Blocks {
@@ -571,7 +583,7 @@ ClusterConfigMessage Structure:
 struct ClusterConfigMessage {
 	string ClientName<64>;
 	string ClientVersion<64>;
-	Folder Folders<>;
+	Folder Folders<1000000>;
 	Option Options<64>;
 }

@@ -610,6 +622,9 @@ func (o ClusterConfigMessage) EncodeXDRInto(xw *xdr.Writer) (int, error) {
 		return xw.Tot(), xdr.ElementSizeExceeded("ClientVersion", l, 64)
 	}
 	xw.WriteString(o.ClientVersion)
+	if l := len(o.Folders); l > 1000000 {
+		return xw.Tot(), xdr.ElementSizeExceeded("Folders", l, 1000000)
+	}
 	xw.WriteUint32(uint32(len(o.Folders)))
 	for i := range o.Folders {
 		_, err := o.Folders[i].EncodeXDRInto(xw)
@@ -646,7 +661,10 @@ func (o *ClusterConfigMessage) DecodeXDRFrom(xr *xdr.Reader) error {
 	o.ClientVersion = xr.ReadStringMax(64)
 	_FoldersSize := int(xr.ReadUint32())
 	if _FoldersSize < 0 {
-		return xdr.ElementSizeExceeded("Folders", _FoldersSize, 0)
+		return xdr.ElementSizeExceeded("Folders", _FoldersSize, 1000000)
+	}
+	if _FoldersSize > 1000000 {
+		return xdr.ElementSizeExceeded("Folders", _FoldersSize, 1000000)
 	}
 	o.Folders = make([]Folder, _FoldersSize)
 	for i := range o.Folders {
@@ -697,7 +715,7 @@ Folder Structure:

 struct Folder {
 	string ID<64>;
-	Device Devices<>;
+	Device Devices<1000000>;
 	unsigned int Flags;
 	Option Options<64>;
 }
@@ -733,6 +751,9 @@ func (o Folder) EncodeXDRInto(xw *xdr.Writer) (int, error) {
 		return xw.Tot(), xdr.ElementSizeExceeded("ID", l, 64)
 	}
 	xw.WriteString(o.ID)
+	if l := len(o.Devices); l > 1000000 {
+		return xw.Tot(), xdr.ElementSizeExceeded("Devices", l, 1000000)
+	}
 	xw.WriteUint32(uint32(len(o.Devices)))
 	for i := range o.Devices {
 		_, err := o.Devices[i].EncodeXDRInto(xw)
@@ -769,7 +790,10 @@ func (o *Folder) DecodeXDRFrom(xr *xdr.Reader) error {
 	o.ID = xr.ReadStringMax(64)
 	_DevicesSize := int(xr.ReadUint32())
 	if _DevicesSize < 0 {
-		return xdr.ElementSizeExceeded("Devices", _DevicesSize, 0)
+		return xdr.ElementSizeExceeded("Devices", _DevicesSize, 1000000)
+	}
+	if _DevicesSize > 1000000 {
+		return xdr.ElementSizeExceeded("Devices", _DevicesSize, 1000000)
 	}
 	o.Devices = make([]Device, _DevicesSize)
 	for i := range o.Devices {
@@ -26,9 +26,9 @@ func (m nativeModel) IndexUpdate(deviceID DeviceID, folder string, files []FileI
 	m.next.IndexUpdate(deviceID, folder, files, flags, options)
 }

-func (m nativeModel) Request(deviceID DeviceID, folder string, name string, offset int64, size int, hash []byte, flags uint32, options []Option) ([]byte, error) {
+func (m nativeModel) Request(deviceID DeviceID, folder string, name string, offset int64, hash []byte, flags uint32, options []Option, buf []byte) error {
 	name = norm.NFD.String(name)
-	return m.next.Request(deviceID, folder, name, offset, size, hash, flags, options)
+	return m.next.Request(deviceID, folder, name, offset, hash, flags, options, buf)
 }

 func (m nativeModel) ClusterConfig(deviceID DeviceID, config ClusterConfigMessage) {
@@ -18,8 +18,8 @@ func (m nativeModel) IndexUpdate(deviceID DeviceID, folder string, files []FileI
 	m.next.IndexUpdate(deviceID, folder, files, flags, options)
 }

-func (m nativeModel) Request(deviceID DeviceID, folder string, name string, offset int64, size int, hash []byte, flags uint32, options []Option) ([]byte, error) {
-	return m.next.Request(deviceID, folder, name, offset, size, hash, flags, options)
+func (m nativeModel) Request(deviceID DeviceID, folder string, name string, offset int64, hash []byte, flags uint32, options []Option, buf []byte) error {
+	return m.next.Request(deviceID, folder, name, offset, hash, flags, options, buf)
 }

 func (m nativeModel) ClusterConfig(deviceID DeviceID, config ClusterConfigMessage) {
@@ -25,18 +25,18 @@ type nativeModel struct {
 }

 func (m nativeModel) Index(deviceID DeviceID, folder string, files []FileInfo, flags uint32, options []Option) {
-	fixupFiles(files)
+	fixupFiles(folder, files)
 	m.next.Index(deviceID, folder, files, flags, options)
 }

 func (m nativeModel) IndexUpdate(deviceID DeviceID, folder string, files []FileInfo, flags uint32, options []Option) {
-	fixupFiles(files)
+	fixupFiles(folder, files)
 	m.next.IndexUpdate(deviceID, folder, files, flags, options)
 }

-func (m nativeModel) Request(deviceID DeviceID, folder string, name string, offset int64, size int, hash []byte, flags uint32, options []Option) ([]byte, error) {
+func (m nativeModel) Request(deviceID DeviceID, folder string, name string, offset int64, hash []byte, flags uint32, options []Option, buf []byte) error {
 	name = filepath.FromSlash(name)
-	return m.next.Request(deviceID, folder, name, offset, size, hash, flags, options)
+	return m.next.Request(deviceID, folder, name, offset, hash, flags, options, buf)
 }

 func (m nativeModel) ClusterConfig(deviceID DeviceID, config ClusterConfigMessage) {
@@ -47,7 +47,7 @@ func (m nativeModel) Close(deviceID DeviceID, err error) {
 	m.next.Close(deviceID, err)
 }

-func fixupFiles(files []FileInfo) {
+func fixupFiles(folder string, files []FileInfo) {
 	for i, f := range files {
 		if strings.ContainsAny(f.Name, disallowedCharacters) {
 			if f.IsDeleted() {
@@ -56,7 +56,7 @@ func fixupFiles(files []FileInfo) {
 				continue
 			}
 			files[i].Flags |= FlagInvalid
-			l.Warnf("File name %q contains invalid characters; marked as invalid.", f.Name)
+			l.Warnf("File name %q (folder %q) contains invalid characters; marked as invalid.", f.Name, folder)
 		}
 		files[i].Name = filepath.FromSlash(files[i].Name)
 	}
@@ -15,7 +15,11 @@ import (
 )

 const (
-	BlockSize = 128 * 1024
+	// Data block size (128 KiB)
+	BlockSize = 128 << 10
+
+	// We reject messages larger than this when encountered on the wire. (64 MiB)
+	MaxMessageLen = 64 << 20
 )

 const (
@@ -31,8 +35,7 @@ const (

 const (
 	stateInitial = iota
-	stateCCRcvd
-	stateIdxRcvd
+	stateReady
 )

 // FileInfo flags
@@ -82,7 +85,7 @@ type Model interface {
 	// An index update was received from the peer device
 	IndexUpdate(deviceID DeviceID, folder string, files []FileInfo, flags uint32, options []Option)
 	// A request was made by the peer device
-	Request(deviceID DeviceID, folder string, name string, offset int64, size int, hash []byte, flags uint32, options []Option) ([]byte, error)
+	Request(deviceID DeviceID, folder string, name string, offset int64, hash []byte, flags uint32, options []Option, buf []byte) error
 	// A cluster configuration message was received
 	ClusterConfig(deviceID DeviceID, config ClusterConfigMessage)
 	// The peer device closed the connection
@@ -90,6 +93,7 @@ type Model interface {
 }

 type Connection interface {
+	Start()
 	ID() DeviceID
 	Name() string
 	Index(folder string, files []FileInfo, flags uint32, options []Option) error
@@ -103,7 +107,6 @@ type rawConnection struct {
 	id       DeviceID
 	name     string
 	receiver Model
-	state    int

 	cr *countingReader
 	cw *countingWriter
@@ -113,11 +116,11 @@ type rawConnection struct {

 	idxMut sync.Mutex // ensures serialization of Index calls

-	nextID chan int
-	outbox chan hdrMsg
-	closed chan struct{}
-	once   sync.Once
-
+	nextID      chan int
+	outbox      chan hdrMsg
+	closed      chan struct{}
+	once        sync.Once
+	pool        sync.Pool
 	compression Compression

 	rdbuf0 []byte // used & reused by readMessage
@@ -130,8 +133,9 @@ type asyncResult struct {
 }

 type hdrMsg struct {
-	hdr header
-	msg encodable
+	hdr  header
+	msg  encodable
+	done chan struct{}
 }

 type encodable interface {
@@ -142,9 +146,9 @@ type isEofer interface {
 	IsEOF() bool
 }

-const (
-	pingTimeout  = 30 * time.Second
-	pingIdleTime = 60 * time.Second
+var (
+	PingTimeout  = 30 * time.Second
+	PingIdleTime = 60 * time.Second
 )

 func NewConnection(deviceID DeviceID, reader io.Reader, writer io.Writer, receiver Model, name string, compress Compression) Connection {
@@ -152,24 +156,32 @@ func NewConnection(deviceID DeviceID, reader io.Reader, writer io.Writer, receiv
 	cw := &countingWriter{Writer: writer}

 	c := rawConnection{
-		id:          deviceID,
-		name:        name,
-		receiver:    nativeModel{receiver},
-		state:       stateInitial,
-		cr:          cr,
-		cw:          cw,
-		outbox:      make(chan hdrMsg),
-		nextID:      make(chan int),
-		closed:      make(chan struct{}),
+		id:       deviceID,
+		name:     name,
+		receiver: nativeModel{receiver},
+		cr:       cr,
+		cw:       cw,
+		outbox:   make(chan hdrMsg),
+		nextID:   make(chan int),
+		closed:   make(chan struct{}),
+		pool: sync.Pool{
+			New: func() interface{} {
+				return make([]byte, BlockSize)
+			},
+		},
 		compression: compress,
 	}

+	return wireFormatConnection{&c}
+}
+
+// Start creates the goroutines for sending and receiving of messages. It must
+// be called exactly once after creating a connection.
+func (c *rawConnection) Start() {
 	go c.readerLoop()
 	go c.writerLoop()
 	go c.pingerLoop()
 	go c.idGenerator()
-
-	return wireFormatConnection{&c}
 }

 func (c *rawConnection) ID() DeviceID {
@@ -193,7 +205,7 @@ func (c *rawConnection) Index(folder string, idx []FileInfo, flags uint32, optio
 		Files:   idx,
 		Flags:   flags,
 		Options: options,
-	})
+	}, nil)
 	c.idxMut.Unlock()
 	return nil
 }
@@ -211,7 +223,7 @@ func (c *rawConnection) IndexUpdate(folder string, idx []FileInfo, flags uint32,
 		Files:   idx,
 		Flags:   flags,
 		Options: options,
-	})
+	}, nil)
 	c.idxMut.Unlock()
 	return nil
 }
@@ -241,7 +253,7 @@ func (c *rawConnection) Request(folder string, name string, offset int64, size i
 		Hash:    hash,
 		Flags:   flags,
 		Options: options,
-	})
+	}, nil)
 	if !ok {
 		return nil, ErrClosed
 	}
@@ -255,7 +267,7 @@ func (c *rawConnection) Request(folder string, name string, offset int64, size i

 // ClusterConfig send the cluster configuration message to the peer and returns any error
 func (c *rawConnection) ClusterConfig(config ClusterConfigMessage) {
-	c.send(-1, messageTypeClusterConfig, config)
+	c.send(-1, messageTypeClusterConfig, config, nil)
 }

 func (c *rawConnection) ping() bool {
@@ -271,7 +283,7 @@ func (c *rawConnection) ping() bool {
 	c.awaiting[id] = rc
 	c.awaitingMut.Unlock()

-	ok := c.send(id, messageTypePing, nil)
+	ok := c.send(id, messageTypePing, nil, nil)
 	if !ok {
 		return false
 	}
@@ -285,6 +297,7 @@ func (c *rawConnection) readerLoop() (err error) {
 		c.close(err)
 	}()

+	state := stateInitial
 	for {
 		select {
 		case <-c.closed:
@@ -298,47 +311,54 @@ func (c *rawConnection) readerLoop() (err error) {
 		}

 		switch msg := msg.(type) {
+		case ClusterConfigMessage:
+			if state != stateInitial {
+				return fmt.Errorf("protocol error: cluster config message in state %d", state)
+			}
+			go c.receiver.ClusterConfig(c.id, msg)
+			state = stateReady
+
 		case IndexMessage:
 			switch hdr.msgType {
 			case messageTypeIndex:
-				if c.state < stateCCRcvd {
-					return fmt.Errorf("protocol error: index message in state %d", c.state)
+				if state != stateReady {
+					return fmt.Errorf("protocol error: index message in state %d", state)
 				}
 				c.handleIndex(msg)
-				c.state = stateIdxRcvd
+				state = stateReady

 			case messageTypeIndexUpdate:
-				if c.state < stateIdxRcvd {
-					return fmt.Errorf("protocol error: index update message in state %d", c.state)
+				if state != stateReady {
+					return fmt.Errorf("protocol error: index update message in state %d", state)
 				}
 				c.handleIndexUpdate(msg)
+				state = stateReady
 			}

 		case RequestMessage:
-			if c.state < stateIdxRcvd {
-				return fmt.Errorf("protocol error: request message in state %d", c.state)
+			if state != stateReady {
+				return fmt.Errorf("protocol error: request message in state %d", state)
 			}
 			// Requests are handled asynchronously
 			go c.handleRequest(hdr.msgID, msg)

 		case ResponseMessage:
-			if c.state < stateIdxRcvd {
-				return fmt.Errorf("protocol error: response message in state %d", c.state)
+			if state != stateReady {
+				return fmt.Errorf("protocol error: response message in state %d", state)
 			}
 			c.handleResponse(hdr.msgID, msg)

 		case pingMessage:
-			c.send(hdr.msgID, messageTypePong, pongMessage{})
+			if state != stateReady {
+				return fmt.Errorf("protocol error: ping message in state %d", state)
+			}
+			c.send(hdr.msgID, messageTypePong, pongMessage{}, nil)

 		case pongMessage:
-			c.handlePong(hdr.msgID)
-
-		case ClusterConfigMessage:
-			if c.state != stateInitial {
-				return fmt.Errorf("protocol error: cluster config message in state %d", c.state)
+			if state != stateReady {
+				return fmt.Errorf("protocol error: pong message in state %d", state)
 			}
-			go c.receiver.ClusterConfig(c.id, msg)
-			c.state = stateCCRcvd
+			c.handlePong(hdr.msgID)

 		case CloseMessage:
 			return errors.New(msg.Reason)
@@ -367,6 +387,11 @@ func (c *rawConnection) readMessage() (hdr header, msg encodable, err error) {
 		l.Debugf("read header %v (msglen=%d)", hdr, msglen)
 	}

+	if msglen > MaxMessageLen {
+		err = fmt.Errorf("message length %d exceeds maximum %d", msglen, MaxMessageLen)
+		return
+	}
+
 	if hdr.version != 0 {
 		err = fmt.Errorf("unknown protocol version 0x%x", hdr.version)
 		return
@@ -387,7 +412,7 @@ func (c *rawConnection) readMessage() (hdr header, msg encodable, err error) {
 	}

 	msgBuf := c.rdbuf0
-	if hdr.compression {
+	if hdr.compression && msglen > 0 {
 		c.rdbuf1 = c.rdbuf1[:cap(c.rdbuf1)]
 		c.rdbuf1, err = lz4.Decode(c.rdbuf1, c.rdbuf0)
 		if err != nil {
@@ -509,12 +534,36 @@ func filterIndexMessageFiles(fs []FileInfo) []FileInfo {
 }

 func (c *rawConnection) handleRequest(msgID int, req RequestMessage) {
-	data, err := c.receiver.Request(c.id, req.Folder, req.Name, int64(req.Offset), int(req.Size), req.Hash, req.Flags, req.Options)
+	size := int(req.Size)
+	usePool := size <= BlockSize

-	c.send(msgID, messageTypeResponse, ResponseMessage{
-		Data: data,
-		Code: errorToCode(err),
-	})
+	var buf []byte
+	var done chan struct{}
+
+	if usePool {
+		buf = c.pool.Get().([]byte)[:size]
+		done = make(chan struct{})
+	} else {
+		buf = make([]byte, size)
+	}
+
+	err := c.receiver.Request(c.id, req.Folder, req.Name, int64(req.Offset), req.Hash, req.Flags, req.Options, buf)
+	if err != nil {
+		c.send(msgID, messageTypeResponse, ResponseMessage{
+			Data: nil,
+			Code: errorToCode(err),
+		}, done)
+	} else {
+		c.send(msgID, messageTypeResponse, ResponseMessage{
+			Data: buf,
+			Code: errorToCode(err),
+		}, done)
+	}
+
+	if usePool {
+		<-done
+		c.pool.Put(buf)
+	}
 }

 func (c *rawConnection) handleResponse(msgID int, resp ResponseMessage) {
@@ -537,7 +586,7 @@ func (c *rawConnection) handlePong(msgID int) {
 	c.awaitingMut.Unlock()
 }

-func (c *rawConnection) send(msgID int, msgType int, msg encodable) bool {
+func (c *rawConnection) send(msgID int, msgType int, msg encodable, done chan struct{}) bool {
 	if msgID < 0 {
 		select {
 		case id := <-c.nextID:
@@ -554,7 +603,7 @@ func (c *rawConnection) send(msgID int, msgType int, msg encodable) bool {
 	}

 	select {
-	case c.outbox <- hdrMsg{hdr, msg}:
+	case c.outbox <- hdrMsg{hdr, msg, done}:
 		return true
 	case <-c.closed:
 		return false
@@ -573,6 +622,9 @@ func (c *rawConnection) writerLoop() {
 			if hm.msg != nil {
 				// Uncompressed message in uncBuf
 				uncBuf, err = hm.msg.AppendXDR(uncBuf[:0])
+				if hm.done != nil {
+					close(hm.done)
+				}
 				if err != nil {
 					c.close(err)
 					return
@@ -679,17 +731,17 @@ func (c *rawConnection) idGenerator() {

 func (c *rawConnection) pingerLoop() {
 	var rc = make(chan bool, 1)
-	ticker := time.Tick(pingIdleTime / 2)
+	ticker := time.Tick(PingIdleTime / 2)
 	for {
 		select {
 		case <-ticker:
-			if d := time.Since(c.cr.Last()); d < pingIdleTime {
+			if d := time.Since(c.cr.Last()); d < PingIdleTime {
 				if debug {
 					l.Debugln(c.id, "ping skipped after rd", d)
 				}
 				continue
 			}
-			if d := time.Since(c.cw.Last()); d < pingIdleTime {
+			if d := time.Since(c.cw.Last()); d < PingIdleTime {
 				if debug {
 					l.Debugln(c.id, "ping skipped after wr", d)
 				}
@@ -709,7 +761,7 @@ func (c *rawConnection) pingerLoop() {
 				if !ok {
 					c.close(fmt.Errorf("ping failure"))
 				}
-			case <-time.After(pingTimeout):
+			case <-time.After(PingTimeout):
 				c.close(fmt.Errorf("ping timeout"))
 			case <-c.closed:
 				return
@@ -67,8 +67,12 @@ func TestPing(t *testing.T) {
 	ar, aw := io.Pipe()
 	br, bw := io.Pipe()

-	c0 := NewConnection(c0ID, ar, bw, nil, "name", CompressAlways).(wireFormatConnection).next.(*rawConnection)
-	c1 := NewConnection(c1ID, br, aw, nil, "name", CompressAlways).(wireFormatConnection).next.(*rawConnection)
+	c0 := NewConnection(c0ID, ar, bw, newTestModel(), "name", CompressAlways).(wireFormatConnection).next.(*rawConnection)
+	c0.Start()
+	c1 := NewConnection(c1ID, br, aw, newTestModel(), "name", CompressAlways).(wireFormatConnection).next.(*rawConnection)
+	c1.Start()
+	c0.ClusterConfig(ClusterConfigMessage{})
+	c1.ClusterConfig(ClusterConfigMessage{})

 	if ok := c0.ping(); !ok {
 		t.Error("c0 ping failed")
@@ -81,8 +85,8 @@ func TestPing(t *testing.T) {
 func TestPingErr(t *testing.T) {
 	e := errors.New("something broke")

-	for i := 0; i < 16; i++ {
-		for j := 0; j < 16; j++ {
+	for i := 0; i < 32; i++ {
+		for j := 0; j < 32; j++ {
 			m0 := newTestModel()
 			m1 := newTestModel()

@@ -92,12 +96,18 @@ func TestPingErr(t *testing.T) {
 			ebw := &ErrPipe{PipeWriter: *bw, max: j, err: e}

 			c0 := NewConnection(c0ID, ar, ebw, m0, "name", CompressAlways).(wireFormatConnection).next.(*rawConnection)
-			NewConnection(c1ID, br, eaw, m1, "name", CompressAlways)
+			c0.Start()
+			c1 := NewConnection(c1ID, br, eaw, m1, "name", CompressAlways)
+			c1.Start()
+			c0.ClusterConfig(ClusterConfigMessage{})
+			c1.ClusterConfig(ClusterConfigMessage{})

 			res := c0.ping()
 			if (i < 8 || j < 8) && res {
+				// This should have resulted in failure, as there is no way an empty ClusterConfig plus a Ping message fits in eight bytes.
 				t.Errorf("Unexpected ping success; i=%d, j=%d", i, j)
-			} else if (i >= 12 && j >= 12) && !res {
+			} else if (i >= 28 && j >= 28) && !res {
+				// This should have worked though, as 28 bytes is plenty for both.
 				t.Errorf("Unexpected ping fail; i=%d, j=%d", i, j)
 			}
 		}
@@ -168,7 +178,11 @@ func TestVersionErr(t *testing.T) {
 	br, bw := io.Pipe()

 	c0 := NewConnection(c0ID, ar, bw, m0, "name", CompressAlways).(wireFormatConnection).next.(*rawConnection)
-	NewConnection(c1ID, br, aw, m1, "name", CompressAlways)
+	c0.Start()
+	c1 := NewConnection(c1ID, br, aw, m1, "name", CompressAlways)
+	c1.Start()
+	c0.ClusterConfig(ClusterConfigMessage{})
+	c1.ClusterConfig(ClusterConfigMessage{})

 	w := xdr.NewWriter(c0.cw)
 	w.WriteUint32(encodeHeader(header{
@@ -191,7 +205,11 @@ func TestTypeErr(t *testing.T) {
 	br, bw := io.Pipe()

 	c0 := NewConnection(c0ID, ar, bw, m0, "name", CompressAlways).(wireFormatConnection).next.(*rawConnection)
-	NewConnection(c1ID, br, aw, m1, "name", CompressAlways)
+	c0.Start()
+	c1 := NewConnection(c1ID, br, aw, m1, "name", CompressAlways)
+	c1.Start()
+	c0.ClusterConfig(ClusterConfigMessage{})
+	c1.ClusterConfig(ClusterConfigMessage{})

 	w := xdr.NewWriter(c0.cw)
 	w.WriteUint32(encodeHeader(header{
@@ -214,7 +232,11 @@ func TestClose(t *testing.T) {
 	br, bw := io.Pipe()

 	c0 := NewConnection(c0ID, ar, bw, m0, "name", CompressAlways).(wireFormatConnection).next.(*rawConnection)
-	NewConnection(c1ID, br, aw, m1, "name", CompressAlways)
+	c0.Start()
+	c1 := NewConnection(c1ID, br, aw, m1, "name", CompressAlways)
+	c1.Start()
+	c0.ClusterConfig(ClusterConfigMessage{})
+	c1.ClusterConfig(ClusterConfigMessage{})

 	c0.close(nil)

@@ -2,6 +2,8 @@

 package protocol

+import "github.com/calmh/xdr"
+
 // This stuff is hacked up manually because genxdr doesn't support 'type
 // Vector []Counter' declarations and it was tricky when I tried to add it...

@@ -28,6 +30,9 @@ func (v Vector) EncodeXDRInto(w xdrWriter) (int, error) {
 // DecodeXDRFrom decodes the XDR objects from the given reader into itself.
 func (v *Vector) DecodeXDRFrom(r xdrReader) error {
 	l := int(r.ReadUint32())
+	if l > 1e6 {
+		return xdr.ElementSizeExceeded("number of counters", l, 1e6)
+	}
 	n := make(Vector, l)
 	for i := range n {
 		n[i].ID = r.ReadUint64()
@@ -12,6 +12,10 @@ type wireFormatConnection struct {
 	next Connection
 }

+func (c wireFormatConnection) Start() {
+	c.next.Start()
+}
+
 func (c wireFormatConnection) ID() DeviceID {
 	return c.next.ID()
 }
@@ -63,13 +63,14 @@ type DB struct {
 	journalAckC  chan error

 	// Compaction.
-	tcompCmdC   chan cCmd
-	tcompPauseC chan chan<- struct{}
-	mcompCmdC   chan cCmd
-	compErrC    chan error
-	compPerErrC chan error
-	compErrSetC chan error
-	compStats   []cStats
+	tcompCmdC        chan cCmd
+	tcompPauseC      chan chan<- struct{}
+	mcompCmdC        chan cCmd
+	compErrC         chan error
+	compPerErrC      chan error
+	compErrSetC      chan error
+	compWriteLocking bool
+	compStats        []cStats

 	// Close.
 	closeW sync.WaitGroup
@@ -108,28 +109,44 @@ func openDB(s *session) (*DB, error) {
 		closeC: make(chan struct{}),
 	}

-	if err := db.recoverJournal(); err != nil {
-		return nil, err
-	}
+	// Read-only mode.
+	readOnly := s.o.GetReadOnly()

-	// Remove any obsolete files.
-	if err := db.checkAndCleanFiles(); err != nil {
-		// Close journal.
-		if db.journal != nil {
-			db.journal.Close()
-			db.journalWriter.Close()
+	if readOnly {
+		// Recover journals (read-only mode).
+		if err := db.recoverJournalRO(); err != nil {
+			return nil, err
 		}
-		return nil, err
+	} else {
+		// Recover journals.
+		if err := db.recoverJournal(); err != nil {
+			return nil, err
+		}
+
+		// Remove any obsolete files.
+		if err := db.checkAndCleanFiles(); err != nil {
+			// Close journal.
+			if db.journal != nil {
+				db.journal.Close()
+				db.journalWriter.Close()
+			}
+			return nil, err
+		}
+
 	}

 	// Doesn't need to be included in the wait group.
 	go db.compactionError()
 	go db.mpoolDrain()

-	db.closeW.Add(3)
-	go db.tCompaction()
-	go db.mCompaction()
-	go db.jWriter()
+	if readOnly {
+		db.SetReadOnly()
+	} else {
+		db.closeW.Add(3)
+		go db.tCompaction()
+		go db.mCompaction()
+		go db.jWriter()
+	}

 	s.logf("db@open done T·%v", time.Since(start))

@@ -274,8 +291,9 @@ func recoverTable(s *session, o *opt.Options) error {

 		// We will drop corrupted table.
 		strict = o.GetStrict(opt.StrictRecovery)
+		noSync = o.GetNoSync()

-		rec   = &sessionRecord{numLevel: o.GetNumLevel()}
+		rec   = &sessionRecord{}
 		bpool = util.NewBufferPool(o.GetBlockSize() + 5)
 	)
 	buildTable := func(iter iterator.Iterator) (tmp storage.File, size int64, err error) {
@@ -311,9 +329,11 @@ func recoverTable(s *session, o *opt.Options) error {
 		if err != nil {
 			return
 		}
-		err = writer.Sync()
-		if err != nil {
-			return
+		if !noSync {
+			err = writer.Sync()
+			if err != nil {
+				return
+			}
 		}
 		size = int64(tw.BytesLen())
 		return
@@ -450,132 +470,136 @@ func recoverTable(s *session, o *opt.Options) error {
 }

 func (db *DB) recoverJournal() error {
-	// Get all tables and sort it by file number.
-	journalFiles_, err := db.s.getFiles(storage.TypeJournal)
+	// Get all journals and sort it by file number.
+	allJournalFiles, err := db.s.getFiles(storage.TypeJournal)
 	if err != nil {
 		return err
 	}
-	journalFiles := files(journalFiles_)
-	journalFiles.sort()
+	files(allJournalFiles).sort()

-	// Discard older journal.
-	prev := -1
-	for i, file := range journalFiles {
-		if file.Num() >= db.s.stJournalNum {
-			if prev >= 0 {
-				i--
-				journalFiles[i] = journalFiles[prev]
-			}
-			journalFiles = journalFiles[i:]
-			break
-		} else if file.Num() == db.s.stPrevJournalNum {
-			prev = i
+	// Journals that will be recovered.
+	var recJournalFiles []storage.File
+	for _, jf := range allJournalFiles {
+		if jf.Num() >= db.s.stJournalNum || jf.Num() == db.s.stPrevJournalNum {
+			recJournalFiles = append(recJournalFiles, jf)
 		}
 	}

-	var jr *journal.Reader
-	var of storage.File
-	var mem *memdb.DB
-	batch := new(Batch)
-	cm := newCMem(db.s)
-	buf := new(util.Buffer)
-	// Options.
-	strict := db.s.o.GetStrict(opt.StrictJournal)
-	checksum := db.s.o.GetStrict(opt.StrictJournalChecksum)
-	writeBuffer := db.s.o.GetWriteBuffer()
-	recoverJournal := func(file storage.File) error {
-		db.logf("journal@recovery recovering @%d", file.Num())
-		reader, err := file.Open()
-		if err != nil {
-			return err
-		}
-		defer reader.Close()
+	var (
+		of  storage.File // Obsolete file.
+		rec = &sessionRecord{}
+	)

-		// Create/reset journal reader instance.
-		if jr == nil {
-			jr = journal.NewReader(reader, dropper{db.s, file}, strict, checksum)
-		} else {
-			jr.Reset(reader, dropper{db.s, file}, strict, checksum)
-		}
-
-		// Flush memdb and remove obsolete journal file.
-		if of != nil {
-			if mem.Len() > 0 {
-				if err := cm.flush(mem, 0); err != nil {
-					return err
-				}
-			}
-			if err := cm.commit(file.Num(), db.seq); err != nil {
-				return err
-			}
-			cm.reset()
-			of.Remove()
-			of = nil
-		}
-
-		// Replay journal to memdb.
-		mem.Reset()
-		for {
-			r, err := jr.Next()
-			if err != nil {
-				if err == io.EOF {
-					break
-				}
-				return errors.SetFile(err, file)
-			}
-
-			buf.Reset()
-			if _, err := buf.ReadFrom(r); err != nil {
-				if err == io.ErrUnexpectedEOF {
-					// This is error returned due to corruption, with strict == false.
-					continue
-				} else {
-					return errors.SetFile(err, file)
-				}
-			}
-			if err := batch.memDecodeAndReplay(db.seq, buf.Bytes(), mem); err != nil {
-				if strict || !errors.IsCorrupted(err) {
-					return errors.SetFile(err, file)
-				} else {
-					db.s.logf("journal error: %v (skipped)", err)
-					// We won't apply sequence number as it might be corrupted.
-					continue
-				}
-			}
-
-			// Save sequence number.
-			db.seq = batch.seq + uint64(batch.Len())
-
-			// Flush it if large enough.
-			if mem.Size() >= writeBuffer {
-				if err := cm.flush(mem, 0); err != nil {
-					return err
-				}
-				mem.Reset()
-			}
-		}
-
-		of = file
-		return nil
-	}
-
-	// Recover all journals.
-	if len(journalFiles) > 0 {
-		db.logf("journal@recovery F·%d", len(journalFiles))
+	// Recover journals.
+	if len(recJournalFiles) > 0 {
+		db.logf("journal@recovery F·%d", len(recJournalFiles))

 		// Mark file number as used.
-		db.s.markFileNum(journalFiles[len(journalFiles)-1].Num())
+		db.s.markFileNum(recJournalFiles[len(recJournalFiles)-1].Num())

-		mem = memdb.New(db.s.icmp, writeBuffer)
-		for _, file := range journalFiles {
-			if err := recoverJournal(file); err != nil {
+		var (
+			// Options.
+			strict      = db.s.o.GetStrict(opt.StrictJournal)
+			checksum    = db.s.o.GetStrict(opt.StrictJournalChecksum)
+			writeBuffer = db.s.o.GetWriteBuffer()
+
+			jr    *journal.Reader
+			mdb   = memdb.New(db.s.icmp, writeBuffer)
+			buf   = &util.Buffer{}
+			batch = &Batch{}
+		)
+
+		for _, jf := range recJournalFiles {
+			db.logf("journal@recovery recovering @%d", jf.Num())
+
+			fr, err := jf.Open()
+			if err != nil {
 				return err
 			}
+
+			// Create or reset journal reader instance.
+			if jr == nil {
+				jr = journal.NewReader(fr, dropper{db.s, jf}, strict, checksum)
+			} else {
+				jr.Reset(fr, dropper{db.s, jf}, strict, checksum)
+			}
+
+			// Flush memdb and remove obsolete journal file.
+			if of != nil {
+				if mdb.Len() > 0 {
+					if _, err := db.s.flushMemdb(rec, mdb, -1); err != nil {
+						fr.Close()
+						return err
+					}
+				}
+
+				rec.setJournalNum(jf.Num())
+				rec.setSeqNum(db.seq)
+				if err := db.s.commit(rec); err != nil {
+					fr.Close()
+					return err
+				}
+				rec.resetAddedTables()
+
+				of.Remove()
+				of = nil
+			}
+
+			// Replay journal to memdb.
+			mdb.Reset()
+			for {
+				r, err := jr.Next()
+				if err != nil {
+					if err == io.EOF {
+						break
+					}
+
+					fr.Close()
+					return errors.SetFile(err, jf)
+				}
+
+				buf.Reset()
+				if _, err := buf.ReadFrom(r); err != nil {
+					if err == io.ErrUnexpectedEOF {
+						// This is error returned due to corruption, with strict == false.
+						continue
+					}
+
+					fr.Close()
+					return errors.SetFile(err, jf)
+				}
+				if err := batch.memDecodeAndReplay(db.seq, buf.Bytes(), mdb); err != nil {
+					if !strict && errors.IsCorrupted(err) {
+						db.s.logf("journal error: %v (skipped)", err)
+						// We won't apply sequence number as it might be corrupted.
+						continue
+					}
+
+					fr.Close()
+					return errors.SetFile(err, jf)
+				}
+
+				// Save sequence number.
+				db.seq = batch.seq + uint64(batch.Len())
+
+				// Flush it if large enough.
+				if mdb.Size() >= writeBuffer {
+					if _, err := db.s.flushMemdb(rec, mdb, 0); err != nil {
+						fr.Close()
+						return err
+					}
+
+					mdb.Reset()
+				}
+			}
+
+			fr.Close()
+			of = jf
 		}

-		// Flush the last journal.
-		if mem.Len() > 0 {
-			if err := cm.flush(mem, 0); err != nil {
+		// Flush the last memdb.
+		if mdb.Len() > 0 {
+			if _, err := db.s.flushMemdb(rec, mdb, 0); err != nil {
 				return err
 			}
 		}
@@ -587,8 +611,10 @@ func (db *DB) recoverJournal() error {
 	}

 	// Commit.
-	if err := cm.commit(db.journalFile.Num(), db.seq); err != nil {
-		// Close journal.
+	rec.setJournalNum(db.journalFile.Num())
+	rec.setSeqNum(db.seq)
+	if err := db.s.commit(rec); err != nil {
+		// Close journal on error.
 		if db.journal != nil {
 			db.journal.Close()
 			db.journalWriter.Close()
@@ -604,6 +630,103 @@ func (db *DB) recoverJournal() error {
 	return nil
 }

+func (db *DB) recoverJournalRO() error {
+	// Get all journals and sort it by file number.
+	allJournalFiles, err := db.s.getFiles(storage.TypeJournal)
+	if err != nil {
+		return err
+	}
+	files(allJournalFiles).sort()
+
+	// Journals that will be recovered.
+	var recJournalFiles []storage.File
+	for _, jf := range allJournalFiles {
+		if jf.Num() >= db.s.stJournalNum || jf.Num() == db.s.stPrevJournalNum {
+			recJournalFiles = append(recJournalFiles, jf)
+		}
+	}
+
+	var (
+		// Options.
+		strict      = db.s.o.GetStrict(opt.StrictJournal)
+		checksum    = db.s.o.GetStrict(opt.StrictJournalChecksum)
+		writeBuffer = db.s.o.GetWriteBuffer()
+
+		mdb = memdb.New(db.s.icmp, writeBuffer)
+	)
+
+	// Recover journals.
+	if len(recJournalFiles) > 0 {
+		db.logf("journal@recovery RO·Mode F·%d", len(recJournalFiles))
+
+		var (
+			jr    *journal.Reader
+			buf   = &util.Buffer{}
+			batch = &Batch{}
+		)
+
+		for _, jf := range recJournalFiles {
+			db.logf("journal@recovery recovering @%d", jf.Num())
+
+			fr, err := jf.Open()
+			if err != nil {
+				return err
+			}
+
+			// Create or reset journal reader instance.
+			if jr == nil {
+				jr = journal.NewReader(fr, dropper{db.s, jf}, strict, checksum)
+			} else {
+				jr.Reset(fr, dropper{db.s, jf}, strict, checksum)
+			}
+
+			// Replay journal to memdb.
+			for {
+				r, err := jr.Next()
+				if err != nil {
+					if err == io.EOF {
+						break
+					}
+
+					fr.Close()
+					return errors.SetFile(err, jf)
+				}
+
+				buf.Reset()
+				if _, err := buf.ReadFrom(r); err != nil {
+					if err == io.ErrUnexpectedEOF {
+						// This is error returned due to corruption, with strict == false.
+						continue
+					}
+
+					fr.Close()
+					return errors.SetFile(err, jf)
+				}
+				if err := batch.memDecodeAndReplay(db.seq, buf.Bytes(), mdb); err != nil {
+					if !strict && errors.IsCorrupted(err) {
+						db.s.logf("journal error: %v (skipped)", err)
+						// We won't apply sequence number as it might be corrupted.
+						continue
+					}
+
+					fr.Close()
+					return errors.SetFile(err, jf)
+				}
+
+				// Save sequence number.
+				db.seq = batch.seq + uint64(batch.Len())
+			}
+
+			fr.Close()
+		}
+	}
+
+	// Set memDB.
+	db.mem = &memDB{db: db, DB: mdb, ref: 1}
+
+	return nil
+}
+
 func (db *DB) get(key []byte, seq uint64, ro *opt.ReadOptions) (value []byte, err error) {
 	ikey := newIkey(key, seq, ktSeek)

@@ -614,7 +737,7 @@ func (db *DB) get(key []byte, seq uint64, ro *opt.ReadOptions) (value []byte, er
 		}
 		defer m.decref()

-		mk, mv, me := m.mdb.Find(ikey)
+		mk, mv, me := m.Find(ikey)
 		if me == nil {
 			ukey, _, kt, kerr := parseIkey(mk)
 			if kerr != nil {
@@ -652,7 +775,7 @@ func (db *DB) has(key []byte, seq uint64, ro *opt.ReadOptions) (ret bool, err er
 		}
 		defer m.decref()

-		mk, _, me := m.mdb.Find(ikey)
+		mk, _, me := m.Find(ikey)
 		if me == nil {
 			ukey, _, kt, kerr := parseIkey(mk)
 			if kerr != nil {
@@ -784,7 +907,7 @@ func (db *DB) GetProperty(name string) (value string, err error) {

 	const prefix = "leveldb."
 	if !strings.HasPrefix(name, prefix) {
-		return "", errors.New("leveldb: GetProperty: unknown property: " + name)
+		return "", ErrNotFound
 	}
 	p := name[len(prefix):]

@@ -798,7 +921,7 @@ func (db *DB) GetProperty(name string) (value string, err error) {
 		var rest string
 		n, _ := fmt.Sscanf(p[len(numFilesPrefix):], "%d%s", &level, &rest)
 		if n != 1 || int(level) >= db.s.o.GetNumLevel() {
-			err = errors.New("leveldb: GetProperty: invalid property: " + name)
+			err = ErrNotFound
 		} else {
 			value = fmt.Sprint(v.tLen(int(level)))
 		}
@@ -837,7 +960,7 @@ func (db *DB) GetProperty(name string) (value string, err error) {
 	case p == "aliveiters":
 		value = fmt.Sprintf("%d", atomic.LoadInt32(&db.aliveIters))
 	default:
-		err = errors.New("leveldb: GetProperty: unknown property: " + name)
+		err = ErrNotFound
 	}

 	return
@@ -900,6 +1023,9 @@ func (db *DB) Close() error {
 	var err error
 	select {
 	case err = <-db.compErrC:
+		if err == ErrReadOnly {
+			err = nil
+		}
 	default:
 	}

@@ -11,7 +11,6 @@ import (
 	"time"

 	"github.com/syndtr/goleveldb/leveldb/errors"
-	"github.com/syndtr/goleveldb/leveldb/memdb"
 	"github.com/syndtr/goleveldb/leveldb/opt"
 )

@@ -62,58 +61,8 @@ func (p *cStatsStaging) stopTimer() {
 	}
 }

-type cMem struct {
-	s     *session
-	level int
-	rec   *sessionRecord
-}
-
-func newCMem(s *session) *cMem {
-	return &cMem{s: s, rec: &sessionRecord{numLevel: s.o.GetNumLevel()}}
-}
-
-func (c *cMem) flush(mem *memdb.DB, level int) error {
-	s := c.s
-
-	// Write memdb to table.
-	iter := mem.NewIterator(nil)
-	defer iter.Release()
-	t, n, err := s.tops.createFrom(iter)
-	if err != nil {
-		return err
-	}
-
-	// Pick level.
-	if level < 0 {
-		v := s.version()
-		level = v.pickLevel(t.imin.ukey(), t.imax.ukey())
-		v.release()
-	}
-	c.rec.addTableFile(level, t)
-
-	s.logf("mem@flush created L%d@%d N·%d S·%s %q:%q", level, t.file.Num(), n, shortenb(int(t.size)), t.imin, t.imax)
-
-	c.level = level
-	return nil
-}
-
-func (c *cMem) reset() {
-	c.rec = &sessionRecord{numLevel: c.s.o.GetNumLevel()}
-}
-
-func (c *cMem) commit(journal, seq uint64) error {
-	c.rec.setJournalNum(journal)
-	c.rec.setSeqNum(seq)
-
-	// Commit changes.
-	return c.s.commit(c.rec)
-}
-
 func (db *DB) compactionError() {
-	var (
-		err     error
-		wlocked bool
-	)
+	var err error
 noerr:
 	// No error.
 	for {
@@ -121,7 +70,7 @@ noerr:
 		case err = <-db.compErrSetC:
 			switch {
 			case err == nil:
-			case errors.IsCorrupted(err):
+			case err == ErrReadOnly, errors.IsCorrupted(err):
 				goto hasperr
 			default:
 				goto haserr
@@ -139,7 +88,7 @@ haserr:
 			switch {
 			case err == nil:
 				goto noerr
-			case errors.IsCorrupted(err):
+			case err == ErrReadOnly, errors.IsCorrupted(err):
 				goto hasperr
 			default:
 			}
@@ -155,9 +104,9 @@ hasperr:
 		case db.compPerErrC <- err:
 		case db.writeLockC <- struct{}{}:
 			// Hold write lock, so that write won't pass-through.
-			wlocked = true
+			db.compWriteLocking = true
 		case _, _ = <-db.closeC:
-			if wlocked {
+			if db.compWriteLocking {
 				// We should release the lock or Close will hang.
 				<-db.writeLockC
 			}
@@ -287,21 +236,18 @@ func (db *DB) compactionExitTransact() {
 }

 func (db *DB) memCompaction() {
-	mem := db.getFrozenMem()
-	if mem == nil {
+	mdb := db.getFrozenMem()
+	if mdb == nil {
 		return
 	}
-	defer mem.decref()
+	defer mdb.decref()

-	c := newCMem(db.s)
-	stats := new(cStatsStaging)
-
-	db.logf("mem@flush N·%d S·%s", mem.mdb.Len(), shortenb(mem.mdb.Size()))
+	db.logf("memdb@flush N·%d S·%s", mdb.Len(), shortenb(mdb.Size()))

 	// Don't compact empty memdb.
-	if mem.mdb.Len() == 0 {
-		db.logf("mem@flush skipping")
-		// drop frozen mem
+	if mdb.Len() == 0 {
+		db.logf("memdb@flush skipping")
+		// drop frozen memdb
 		db.dropFrozenMem()
 		return
 	}
@@ -317,13 +263,20 @@ func (db *DB) memCompaction() {
 		return
 	}

-	db.compactionTransactFunc("mem@flush", func(cnt *compactionTransactCounter) (err error) {
+	var (
+		rec        = &sessionRecord{}
+		stats      = &cStatsStaging{}
+		flushLevel int
+	)
+
+	db.compactionTransactFunc("memdb@flush", func(cnt *compactionTransactCounter) (err error) {
 		stats.startTimer()
-		defer stats.stopTimer()
-		return c.flush(mem.mdb, -1)
+		flushLevel, err = db.s.flushMemdb(rec, mdb.DB, -1)
+		stats.stopTimer()
+		return
 	}, func() error {
-		for _, r := range c.rec.addedTables {
-			db.logf("mem@flush revert @%d", r.num)
+		for _, r := range rec.addedTables {
+			db.logf("memdb@flush revert @%d", r.num)
 			f := db.s.getTableFile(r.num)
 			if err := f.Remove(); err != nil {
 				return err
@@ -332,20 +285,23 @@ func (db *DB) memCompaction() {
 		return nil
 	})

-	db.compactionTransactFunc("mem@commit", func(cnt *compactionTransactCounter) (err error) {
+	db.compactionTransactFunc("memdb@commit", func(cnt *compactionTransactCounter) (err error) {
 		stats.startTimer()
-		defer stats.stopTimer()
-		return c.commit(db.journalFile.Num(), db.frozenSeq)
+		rec.setJournalNum(db.journalFile.Num())
+		rec.setSeqNum(db.frozenSeq)
+		err = db.s.commit(rec)
+		stats.stopTimer()
+		return
 	}, nil)

-	db.logf("mem@flush committed F·%d T·%v", len(c.rec.addedTables), stats.duration)
+	db.logf("memdb@flush committed F·%d T·%v", len(rec.addedTables), stats.duration)

-	for _, r := range c.rec.addedTables {
+	for _, r := range rec.addedTables {
 		stats.write += r.size
 	}
-	db.compStats[c.level].add(stats)
+	db.compStats[flushLevel].add(stats)

-	// Drop frozen mem.
+	// Drop frozen memdb.
 	db.dropFrozenMem()

 	// Resume table compaction.
@@ -557,7 +513,7 @@ func (b *tableCompactionBuilder) revert() error {
 func (db *DB) tableCompaction(c *compaction, noTrivial bool) {
 	defer c.release()

-	rec := &sessionRecord{numLevel: db.s.o.GetNumLevel()}
+	rec := &sessionRecord{}
 	rec.addCompPtr(c.level, c.imax)

 	if !noTrivial && c.trivial() {
@@ -8,6 +8,7 @@ package leveldb

 import (
 	"errors"
+	"math/rand"
 	"runtime"
 	"sync"
 	"sync/atomic"
@@ -39,11 +40,11 @@ func (db *DB) newRawIterator(slice *util.Range, ro *opt.ReadOptions) iterator.It
 	ti := v.getIterators(slice, ro)
 	n := len(ti) + 2
 	i := make([]iterator.Iterator, 0, n)
-	emi := em.mdb.NewIterator(slice)
+	emi := em.NewIterator(slice)
 	emi.SetReleaser(&memdbReleaser{m: em})
 	i = append(i, emi)
 	if fm != nil {
-		fmi := fm.mdb.NewIterator(slice)
+		fmi := fm.NewIterator(slice)
 		fmi.SetReleaser(&memdbReleaser{m: fm})
 		i = append(i, fmi)
 	}
@@ -80,6 +81,10 @@ func (db *DB) newIterator(seq uint64, slice *util.Range, ro *opt.ReadOptions) *d
 	return iter
 }

+func (db *DB) iterSamplingRate() int {
+	return rand.Intn(2 * db.s.o.GetIteratorSamplingRate())
+}
+
 type dir int

 const (
@@ -98,11 +103,21 @@ type dbIter struct {
 	seq    uint64
 	strict bool

-	dir      dir
-	key      []byte
-	value    []byte
-	err      error
-	releaser util.Releaser
+	smaplingGap int
+	dir         dir
+	key         []byte
+	value       []byte
+	err         error
+	releaser    util.Releaser
+}
+
+func (i *dbIter) sampleSeek() {
+	ikey := i.iter.Key()
+	i.smaplingGap -= len(ikey) + len(i.iter.Value())
+	for i.smaplingGap < 0 {
+		i.smaplingGap += i.db.iterSamplingRate()
+		i.db.sampleSeek(ikey)
+	}
 }

 func (i *dbIter) setErr(err error) {
@@ -175,6 +190,7 @@ func (i *dbIter) Seek(key []byte) bool {
 func (i *dbIter) next() bool {
 	for {
 		if ukey, seq, kt, kerr := parseIkey(i.iter.Key()); kerr == nil {
+			i.sampleSeek()
 			if seq <= i.seq {
 				switch kt {
 				case ktDel:
@@ -225,6 +241,7 @@ func (i *dbIter) prev() bool {
 	if i.iter.Valid() {
 		for {
 			if ukey, seq, kt, kerr := parseIkey(i.iter.Key()); kerr == nil {
+				i.sampleSeek()
 				if seq <= i.seq {
 					if !del && i.icmp.uCompare(ukey, i.key) < 0 {
 						return true
@@ -266,6 +283,7 @@ func (i *dbIter) Prev() bool {
 	case dirForward:
 		for i.iter.Prev() {
 			if ukey, _, _, kerr := parseIkey(i.iter.Key()); kerr == nil {
+				i.sampleSeek()
 				if i.icmp.uCompare(ukey, i.key) < 0 {
 					goto cont
 				}
@@ -15,8 +15,8 @@ import (
 )

 type memDB struct {
-	db  *DB
-	mdb *memdb.DB
+	db *DB
+	*memdb.DB
 	ref int32
 }

@@ -27,12 +27,12 @@ func (m *memDB) incref() {
 func (m *memDB) decref() {
 	if ref := atomic.AddInt32(&m.ref, -1); ref == 0 {
 		// Only put back memdb with std capacity.
-		if m.mdb.Capacity() == m.db.s.o.GetWriteBuffer() {
-			m.mdb.Reset()
-			m.db.mpoolPut(m.mdb)
+		if m.Capacity() == m.db.s.o.GetWriteBuffer() {
+			m.Reset()
+			m.db.mpoolPut(m.DB)
 		}
 		m.db = nil
-		m.mdb = nil
+		m.DB = nil
 	} else if ref < 0 {
 		panic("negative memdb ref")
 	}
@@ -48,6 +48,15 @@ func (db *DB) addSeq(delta uint64) {
 	atomic.AddUint64(&db.seq, delta)
 }

+func (db *DB) sampleSeek(ikey iKey) {
+	v := db.s.version()
+	if v.sampleSeek(ikey) {
+		// Trigger table compaction.
+		db.compSendTrigger(db.tcompCmdC)
+	}
+	v.release()
+}
+
 func (db *DB) mpoolPut(mem *memdb.DB) {
 	defer func() {
 		recover()
@@ -117,7 +126,7 @@ func (db *DB) newMem(n int) (mem *memDB, err error) {
 	}
 	mem = &memDB{
 		db:  db,
-		mdb: mdb,
+		DB:  mdb,
 		ref: 2,
 	}
 	db.mem = mem
@@ -405,19 +405,21 @@ func (h *dbHarness) compactRange(min, max string) {
 	t.Log("DB range compaction done")
 }

-func (h *dbHarness) sizeAssert(start, limit string, low, hi uint64) {
-	t := h.t
-	db := h.db
-
-	s, err := db.SizeOf([]util.Range{
+func (h *dbHarness) sizeOf(start, limit string) uint64 {
+	sz, err := h.db.SizeOf([]util.Range{
 		{[]byte(start), []byte(limit)},
 	})
 	if err != nil {
-		t.Error("SizeOf: got error: ", err)
+		h.t.Error("SizeOf: got error: ", err)
 	}
-	if s.Sum() < low || s.Sum() > hi {
-		t.Errorf("sizeof %q to %q not in range, want %d - %d, got %d",
-			shorten(start), shorten(limit), low, hi, s.Sum())
+	return sz.Sum()
+}
+
+func (h *dbHarness) sizeAssert(start, limit string, low, hi uint64) {
+	sz := h.sizeOf(start, limit)
+	if sz < low || sz > hi {
+		h.t.Errorf("sizeOf %q to %q not in range, want %d - %d, got %d",
+			shorten(start), shorten(limit), low, hi, sz)
 	}
 }

@@ -2443,7 +2445,7 @@ func TestDB_TableCompactionBuilder(t *testing.T) {
 		if err != nil {
 			t.Fatal(err)
 		}
-		rec := &sessionRecord{numLevel: s.o.GetNumLevel()}
+		rec := &sessionRecord{}
 		rec.addTableFile(i, tf)
 		if err := s.commit(rec); err != nil {
 			t.Fatal(err)
@@ -2453,7 +2455,7 @@ func TestDB_TableCompactionBuilder(t *testing.T) {
 	// Build grandparent.
 	v := s.version()
 	c := newCompaction(s, v, 1, append(tFiles{}, v.tables[1]...))
-	rec := &sessionRecord{numLevel: s.o.GetNumLevel()}
+	rec := &sessionRecord{}
 	b := &tableCompactionBuilder{
 		s:         s,
 		c:         c,
@@ -2477,7 +2479,7 @@ func TestDB_TableCompactionBuilder(t *testing.T) {
 	// Build level-1.
 	v = s.version()
 	c = newCompaction(s, v, 0, append(tFiles{}, v.tables[0]...))
-	rec = &sessionRecord{numLevel: s.o.GetNumLevel()}
+	rec = &sessionRecord{}
 	b = &tableCompactionBuilder{
 		s:         s,
 		c:         c,
@@ -2521,7 +2523,7 @@ func TestDB_TableCompactionBuilder(t *testing.T) {
 	// Compaction with transient error.
 	v = s.version()
 	c = newCompaction(s, v, 1, append(tFiles{}, v.tables[1]...))
-	rec = &sessionRecord{numLevel: s.o.GetNumLevel()}
+	rec = &sessionRecord{}
 	b = &tableCompactionBuilder{
 		s:         s,
 		c:         c,
@@ -2577,3 +2579,123 @@ func TestDB_TableCompactionBuilder(t *testing.T) {
 	}
 	v.release()
 }
+
+func testDB_IterTriggeredCompaction(t *testing.T, limitDiv int) {
+	const (
+		vSize = 200 * opt.KiB
+		tSize = 100 * opt.MiB
+		mIter = 100
+		n     = tSize / vSize
+	)
+
+	h := newDbHarnessWopt(t, &opt.Options{
+		Compression:       opt.NoCompression,
+		DisableBlockCache: true,
+	})
+	defer h.close()
+
+	key := func(x int) string {
+		return fmt.Sprintf("v%06d", x)
+	}
+
+	// Fill.
+	value := strings.Repeat("x", vSize)
+	for i := 0; i < n; i++ {
+		h.put(key(i), value)
+	}
+	h.compactMem()
+
+	// Delete all.
+	for i := 0; i < n; i++ {
+		h.delete(key(i))
+	}
+	h.compactMem()
+
+	var (
+		limit = n / limitDiv
+
+		startKey = key(0)
+		limitKey = key(limit)
+		maxKey   = key(n)
+		slice    = &util.Range{Limit: []byte(limitKey)}
+
+		initialSize0 = h.sizeOf(startKey, limitKey)
+		initialSize1 = h.sizeOf(limitKey, maxKey)
+	)
+
+	t.Logf("inital size %s [rest %s]", shortenb(int(initialSize0)), shortenb(int(initialSize1)))
+
+	for r := 0; true; r++ {
+		if r >= mIter {
+			t.Fatal("taking too long to compact")
+		}
+
+		// Iterates.
+		iter := h.db.NewIterator(slice, h.ro)
+		for iter.Next() {
+		}
+		if err := iter.Error(); err != nil {
+			t.Fatalf("Iter err: %v", err)
+		}
+		iter.Release()
+
+		// Wait compaction.
+		h.waitCompaction()
+
+		// Check size.
+		size0 := h.sizeOf(startKey, limitKey)
+		size1 := h.sizeOf(limitKey, maxKey)
+		t.Logf("#%03d size %s [rest %s]", r, shortenb(int(size0)), shortenb(int(size1)))
+		if size0 < initialSize0/10 {
+			break
+		}
+	}
+
+	if initialSize1 > 0 {
+		h.sizeAssert(limitKey, maxKey, initialSize1/4-opt.MiB, initialSize1+opt.MiB)
+	}
+}
+
+func TestDB_IterTriggeredCompaction(t *testing.T) {
+	testDB_IterTriggeredCompaction(t, 1)
+}
+
+func TestDB_IterTriggeredCompactionHalf(t *testing.T) {
+	testDB_IterTriggeredCompaction(t, 2)
+}
+
+func TestDB_ReadOnly(t *testing.T) {
+	h := newDbHarness(t)
+	defer h.close()
+
+	h.put("foo", "v1")
+	h.put("bar", "v2")
+	h.compactMem()
+
+	h.put("xfoo", "v1")
+	h.put("xbar", "v2")
+
+	t.Log("Trigger read-only")
+	if err := h.db.SetReadOnly(); err != nil {
+		h.close()
+		t.Fatalf("SetReadOnly error: %v", err)
+	}
+
+	h.stor.SetEmuErr(storage.TypeAll, tsOpCreate, tsOpReplace, tsOpRemove, tsOpWrite, tsOpWrite, tsOpSync)
+
+	ro := func(key, value, wantValue string) {
+		if err := h.db.Put([]byte(key), []byte(value), h.wo); err != ErrReadOnly {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		h.getVal(key, wantValue)
+	}
+
+	ro("foo", "vx", "v1")
+
+	h.o.ReadOnly = true
+	h.reopenDB()
+
+	ro("foo", "vx", "v1")
+	ro("bar", "vx", "v2")
+	h.assertNumKeys(4)
+}
@@ -63,24 +63,24 @@ func (db *DB) rotateMem(n int) (mem *memDB, err error) {
 	return
 }

-func (db *DB) flush(n int) (mem *memDB, nn int, err error) {
+func (db *DB) flush(n int) (mdb *memDB, mdbFree int, err error) {
 	delayed := false
 	flush := func() (retry bool) {
 		v := db.s.version()
 		defer v.release()
-		mem = db.getEffectiveMem()
+		mdb = db.getEffectiveMem()
 		defer func() {
 			if retry {
-				mem.decref()
-				mem = nil
+				mdb.decref()
+				mdb = nil
 			}
 		}()
-		nn = mem.mdb.Free()
+		mdbFree = mdb.Free()
 		switch {
 		case v.tLen(0) >= db.s.o.GetWriteL0SlowdownTrigger() && !delayed:
 			delayed = true
 			time.Sleep(time.Millisecond)
-		case nn >= n:
+		case mdbFree >= n:
 			return false
 		case v.tLen(0) >= db.s.o.GetWriteL0PauseTrigger():
 			delayed = true
@@ -90,15 +90,15 @@ func (db *DB) flush(n int) (mem *memDB, nn int, err error) {
 			}
 		default:
 			// Allow memdb to grow if it has no entry.
-			if mem.mdb.Len() == 0 {
-				nn = n
+			if mdb.Len() == 0 {
+				mdbFree = n
 			} else {
-				mem.decref()
-				mem, err = db.rotateMem(n)
+				mdb.decref()
+				mdb, err = db.rotateMem(n)
 				if err == nil {
-					nn = mem.mdb.Free()
+					mdbFree = mdb.Free()
 				} else {
-					nn = 0
+					mdbFree = 0
 				}
 			}
 			return false
@@ -129,7 +129,7 @@ func (db *DB) Write(b *Batch, wo *opt.WriteOptions) (err error) {
 		return
 	}

-	b.init(wo.GetSync())
+	b.init(wo.GetSync() && !db.s.o.GetNoSync())

 	// The write happen synchronously.
 	select {
@@ -157,18 +157,18 @@ func (db *DB) Write(b *Batch, wo *opt.WriteOptions) (err error) {
 		}
 	}()

-	mem, memFree, err := db.flush(b.size())
+	mdb, mdbFree, err := db.flush(b.size())
 	if err != nil {
 		return
 	}
-	defer mem.decref()
+	defer mdb.decref()

 	// Calculate maximum size of the batch.
 	m := 1 << 20
 	if x := b.size(); x <= 128<<10 {
 		m = x + (128 << 10)
 	}
-	m = minInt(m, memFree)
+	m = minInt(m, mdbFree)

 	// Merge with other batch.
 drain:
@@ -197,7 +197,7 @@ drain:
 		select {
 		case db.journalC <- b:
 			// Write into memdb
-			if berr := b.memReplay(mem.mdb); berr != nil {
+			if berr := b.memReplay(mdb.DB); berr != nil {
 				panic(berr)
 			}
 		case err = <-db.compPerErrC:
@@ -211,7 +211,7 @@ drain:
 		case err = <-db.journalAckC:
 			if err != nil {
 				// Revert memdb if error detected
-				if berr := b.revertMemReplay(mem.mdb); berr != nil {
+				if berr := b.revertMemReplay(mdb.DB); berr != nil {
 					panic(berr)
 				}
 				return
@@ -225,7 +225,7 @@ drain:
 		if err != nil {
 			return
 		}
-		if berr := b.memReplay(mem.mdb); berr != nil {
+		if berr := b.memReplay(mdb.DB); berr != nil {
 			panic(berr)
 		}
 	}
@@ -233,7 +233,7 @@ drain:
 	// Set last seq number.
 	db.addSeq(uint64(b.Len()))

-	if b.size() >= memFree {
+	if b.size() >= mdbFree {
 		db.rotateMem(0)
 	}
 	return
@@ -249,8 +249,7 @@ func (db *DB) Put(key, value []byte, wo *opt.WriteOptions) error {
 	return db.Write(b, wo)
 }

-// Delete deletes the value for the given key. It returns ErrNotFound if
-// the DB does not contain the key.
+// Delete deletes the value for the given key.
 //
 // It is safe to modify the contents of the arguments after Delete returns.
 func (db *DB) Delete(key []byte, wo *opt.WriteOptions) error {
@@ -290,9 +289,9 @@ func (db *DB) CompactRange(r util.Range) error {
 	}

 	// Check for overlaps in memdb.
-	mem := db.getEffectiveMem()
-	defer mem.decref()
-	if isMemOverlaps(db.s.icmp, mem.mdb, r.Start, r.Limit) {
+	mdb := db.getEffectiveMem()
+	defer mdb.decref()
+	if isMemOverlaps(db.s.icmp, mdb.DB, r.Start, r.Limit) {
 		// Memdb compaction.
 		if _, err := db.rotateMem(0); err != nil {
 			<-db.writeLockC
@@ -309,3 +308,31 @@ func (db *DB) CompactRange(r util.Range) error {
 	// Table compaction.
 	return db.compSendRange(db.tcompCmdC, -1, r.Start, r.Limit)
 }
+
+// SetReadOnly makes DB read-only. It will stay read-only until reopened.
+func (db *DB) SetReadOnly() error {
+	if err := db.ok(); err != nil {
+		return err
+	}
+
+	// Lock writer.
+	select {
+	case db.writeLockC <- struct{}{}:
+		db.compWriteLocking = true
+	case err := <-db.compPerErrC:
+		return err
+	case _, _ = <-db.closeC:
+		return ErrClosed
+	}
+
+	// Set compaction read-only.
+	select {
+	case db.compErrSetC <- ErrReadOnly:
+	case perr := <-db.compPerErrC:
+		return perr
+	case _, _ = <-db.closeC:
+		return ErrClosed
+	}
+
+	return nil
+}
@@ -12,6 +12,7 @@ import (

 var (
 	ErrNotFound         = errors.ErrNotFound
+	ErrReadOnly         = errors.New("leveldb: read-only mode")
 	ErrSnapshotReleased = errors.New("leveldb: snapshot released")
 	ErrIterReleased     = errors.New("leveldb: iterator released")
 	ErrClosed           = errors.New("leveldb: closed")
@@ -52,12 +52,14 @@ func IsCorrupted(err error) bool {
 	switch err.(type) {
 	case *ErrCorrupted:
 		return true
+	case *storage.ErrCorrupted:
+		return true
 	}
 	return false
 }

 // ErrMissingFiles is the type that indicating a corruption due to missing
-// files.
+// files. ErrMissingFiles always wrapped with ErrCorrupted.
 type ErrMissingFiles struct {
 	Files []*storage.FileInfo
 }
@@ -206,6 +206,7 @@ func (p *DB) randHeight() (h int) {
 	return
 }

+// Must hold RW-lock if prev == true, as it use shared prevNode slice.
 func (p *DB) findGE(key []byte, prev bool) (int, bool) {
 	node := 0
 	h := p.maxHeight - 1
@@ -302,7 +303,7 @@ func (p *DB) Put(key []byte, value []byte) error {
 	node := len(p.nodeData)
 	p.nodeData = append(p.nodeData, kvOffset, len(key), len(value), h)
 	for i, n := range p.prevNode[:h] {
-		m := n + 4 + i
+		m := n + nNext + i
 		p.nodeData = append(p.nodeData, p.nodeData[m])
 		p.nodeData[m] = node
 	}
@@ -434,20 +435,22 @@ func (p *DB) Len() int {

 // Reset resets the DB to initial empty state. Allows reuse the buffer.
 func (p *DB) Reset() {
+	p.mu.Lock()
 	p.rnd = rand.New(rand.NewSource(0xdeadbeef))
 	p.maxHeight = 1
 	p.n = 0
 	p.kvSize = 0
 	p.kvData = p.kvData[:0]
-	p.nodeData = p.nodeData[:4+tMaxHeight]
+	p.nodeData = p.nodeData[:nNext+tMaxHeight]
 	p.nodeData[nKV] = 0
 	p.nodeData[nKey] = 0
 	p.nodeData[nVal] = 0
 	p.nodeData[nHeight] = tMaxHeight
 	for n := 0; n < tMaxHeight; n++ {
-		p.nodeData[4+n] = 0
+		p.nodeData[nNext+n] = 0
 		p.prevNode[n] = 0
 	}
+	p.mu.Unlock()
 }

 // New creates a new initalized in-memory key/value DB. The capacity
@@ -34,10 +34,11 @@ var (
 	DefaultCompactionTotalSize           = 10 * MiB
 	DefaultCompactionTotalSizeMultiplier = 10.0
 	DefaultCompressionType               = SnappyCompression
-	DefaultOpenFilesCacher               = LRUCacher
-	DefaultOpenFilesCacheCapacity        = 500
+	DefaultIteratorSamplingRate          = 1 * MiB
 	DefaultMaxMemCompationLevel          = 2
 	DefaultNumLevel                      = 7
+	DefaultOpenFilesCacher               = LRUCacher
+	DefaultOpenFilesCacheCapacity        = 500
 	DefaultWriteBuffer                   = 4 * MiB
 	DefaultWriteL0PauseTrigger           = 12
 	DefaultWriteL0SlowdownTrigger        = 8
@@ -249,6 +250,11 @@ type Options struct {
 	// The default value (DefaultCompression) uses snappy compression.
 	Compression Compression

+	// DisableBufferPool allows disable use of util.BufferPool functionality.
+	//
+	// The default value is false.
+	DisableBufferPool bool
+
 	// DisableBlockCache allows disable use of cache.Cache functionality on
 	// 'sorted table' block.
 	//
@@ -288,6 +294,13 @@ type Options struct {
 	// The default value is nil.
 	Filter filter.Filter

+	// IteratorSamplingRate defines approximate gap (in bytes) between read
+	// sampling of an iterator. The samples will be used to determine when
+	// compaction should be triggered.
+	//
+	// The default is 1MiB.
+	IteratorSamplingRate int
+
 	// MaxMemCompationLevel defines maximum level a newly compacted 'memdb'
 	// will be pushed into if doesn't creates overlap. This should less than
 	// NumLevel. Use -1 for level-0.
@@ -295,6 +308,11 @@ type Options struct {
 	// The default is 2.
 	MaxMemCompationLevel int

+	// NoSync allows completely disable fsync.
+	//
+	// The default is false.
+	NoSync bool
+
 	// NumLevel defines number of database level. The level shouldn't changed
 	// between opens, or the database will panic.
 	//
@@ -313,6 +331,11 @@ type Options struct {
 	// The default value is 500.
 	OpenFilesCacheCapacity int

+	// If true then opens DB in read-only mode.
+	//
+	// The default value is false.
+	ReadOnly bool
+
 	// Strict defines the DB strict level.
 	Strict Strict

@@ -464,6 +487,20 @@ func (o *Options) GetCompression() Compression {
 	return o.Compression
 }

+func (o *Options) GetDisableBufferPool() bool {
+	if o == nil {
+		return false
+	}
+	return o.DisableBufferPool
+}
+
+func (o *Options) GetDisableBlockCache() bool {
+	if o == nil {
+		return false
+	}
+	return o.DisableBlockCache
+}
+
 func (o *Options) GetDisableCompactionBackoff() bool {
 	if o == nil {
 		return false
@@ -492,6 +529,13 @@ func (o *Options) GetFilter() filter.Filter {
 	return o.Filter
 }

+func (o *Options) GetIteratorSamplingRate() int {
+	if o == nil || o.IteratorSamplingRate <= 0 {
+		return DefaultIteratorSamplingRate
+	}
+	return o.IteratorSamplingRate
+}
+
 func (o *Options) GetMaxMemCompationLevel() int {
 	level := DefaultMaxMemCompationLevel
 	if o != nil {
@@ -507,6 +551,13 @@ func (o *Options) GetMaxMemCompationLevel() int {
 	return level
 }

+func (o *Options) GetNoSync() bool {
+	if o == nil {
+		return false
+	}
+	return o.NoSync
+}
+
 func (o *Options) GetNumLevel() int {
 	if o == nil || o.NumLevel <= 0 {
 		return DefaultNumLevel
@@ -533,6 +584,13 @@ func (o *Options) GetOpenFilesCacheCapacity() int {
 	return o.OpenFilesCacheCapacity
 }

+func (o *Options) GetReadOnly() bool {
+	if o == nil {
+		return false
+	}
+	return o.ReadOnly
+}
+
 func (o *Options) GetStrict(strict Strict) bool {
 	if o == nil || o.Strict == 0 {
 		return DefaultStrict&strict != 0
@@ -11,10 +11,8 @@ import (
 	"io"
 	"os"
 	"sync"
-	"sync/atomic"

 	"github.com/syndtr/goleveldb/leveldb/errors"
-	"github.com/syndtr/goleveldb/leveldb/iterator"
 	"github.com/syndtr/goleveldb/leveldb/journal"
 	"github.com/syndtr/goleveldb/leveldb/opt"
 	"github.com/syndtr/goleveldb/leveldb/storage"
@@ -127,11 +125,16 @@ func (s *session) recover() (err error) {
 		return
 	}
 	defer reader.Close()
-	strict := s.o.GetStrict(opt.StrictManifest)
-	jr := journal.NewReader(reader, dropper{s, m}, strict, true)

-	staging := s.stVersion.newStaging()
-	rec := &sessionRecord{numLevel: s.o.GetNumLevel()}
+	var (
+		// Options.
+		numLevel = s.o.GetNumLevel()
+		strict   = s.o.GetStrict(opt.StrictManifest)
+
+		jr      = journal.NewReader(reader, dropper{s, m}, strict, true)
+		rec     = &sessionRecord{}
+		staging = s.stVersion.newStaging()
+	)
 	for {
 		var r io.Reader
 		r, err = jr.Next()
@@ -143,7 +146,7 @@ func (s *session) recover() (err error) {
 			return errors.SetFile(err, m)
 		}

-		err = rec.decode(r)
+		err = rec.decode(r, numLevel)
 		if err == nil {
 			// save compact pointers
 			for _, r := range rec.compPtrs {
@@ -206,250 +209,3 @@ func (s *session) commit(r *sessionRecord) (err error) {

 	return
 }
-
-// Pick a compaction based on current state; need external synchronization.
-func (s *session) pickCompaction() *compaction {
-	v := s.version()
-
-	var level int
-	var t0 tFiles
-	if v.cScore >= 1 {
-		level = v.cLevel
-		cptr := s.stCompPtrs[level]
-		tables := v.tables[level]
-		for _, t := range tables {
-			if cptr == nil || s.icmp.Compare(t.imax, cptr) > 0 {
-				t0 = append(t0, t)
-				break
-			}
-		}
-		if len(t0) == 0 {
-			t0 = append(t0, tables[0])
-		}
-	} else {
-		if p := atomic.LoadPointer(&v.cSeek); p != nil {
-			ts := (*tSet)(p)
-			level = ts.level
-			t0 = append(t0, ts.table)
-		} else {
-			v.release()
-			return nil
-		}
-	}
-
-	return newCompaction(s, v, level, t0)
-}
-
-// Create compaction from given level and range; need external synchronization.
-func (s *session) getCompactionRange(level int, umin, umax []byte) *compaction {
-	v := s.version()
-
-	t0 := v.tables[level].getOverlaps(nil, s.icmp, umin, umax, level == 0)
-	if len(t0) == 0 {
-		v.release()
-		return nil
-	}
-
-	// Avoid compacting too much in one shot in case the range is large.
-	// But we cannot do this for level-0 since level-0 files can overlap
-	// and we must not pick one file and drop another older file if the
-	// two files overlap.
-	if level > 0 {
-		limit := uint64(v.s.o.GetCompactionSourceLimit(level))
-		total := uint64(0)
-		for i, t := range t0 {
-			total += t.size
-			if total >= limit {
-				s.logf("table@compaction limiting F·%d -> F·%d", len(t0), i+1)
-				t0 = t0[:i+1]
-				break
-			}
-		}
-	}
-
-	return newCompaction(s, v, level, t0)
-}
-
-func newCompaction(s *session, v *version, level int, t0 tFiles) *compaction {
-	c := &compaction{
-		s:             s,
-		v:             v,
-		level:         level,
-		tables:        [2]tFiles{t0, nil},
-		maxGPOverlaps: uint64(s.o.GetCompactionGPOverlaps(level)),
-		tPtrs:         make([]int, s.o.GetNumLevel()),
-	}
-	c.expand()
-	c.save()
-	return c
-}
-
-// compaction represent a compaction state.
-type compaction struct {
-	s *session
-	v *version
-
-	level         int
-	tables        [2]tFiles
-	maxGPOverlaps uint64
-
-	gp                tFiles
-	gpi               int
-	seenKey           bool
-	gpOverlappedBytes uint64
-	imin, imax        iKey
-	tPtrs             []int
-	released          bool
-
-	snapGPI               int
-	snapSeenKey           bool
-	snapGPOverlappedBytes uint64
-	snapTPtrs             []int
-}
-
-func (c *compaction) save() {
-	c.snapGPI = c.gpi
-	c.snapSeenKey = c.seenKey
-	c.snapGPOverlappedBytes = c.gpOverlappedBytes
-	c.snapTPtrs = append(c.snapTPtrs[:0], c.tPtrs...)
-}
-
-func (c *compaction) restore() {
-	c.gpi = c.snapGPI
-	c.seenKey = c.snapSeenKey
-	c.gpOverlappedBytes = c.snapGPOverlappedBytes
-	c.tPtrs = append(c.tPtrs[:0], c.snapTPtrs...)
-}
-
-func (c *compaction) release() {
-	if !c.released {
-		c.released = true
-		c.v.release()
-	}
-}
-
-// Expand compacted tables; need external synchronization.
-func (c *compaction) expand() {
-	limit := uint64(c.s.o.GetCompactionExpandLimit(c.level))
-	vt0, vt1 := c.v.tables[c.level], c.v.tables[c.level+1]
-
-	t0, t1 := c.tables[0], c.tables[1]
-	imin, imax := t0.getRange(c.s.icmp)
-	// We expand t0 here just incase ukey hop across tables.
-	t0 = vt0.getOverlaps(t0, c.s.icmp, imin.ukey(), imax.ukey(), c.level == 0)
-	if len(t0) != len(c.tables[0]) {
-		imin, imax = t0.getRange(c.s.icmp)
-	}
-	t1 = vt1.getOverlaps(t1, c.s.icmp, imin.ukey(), imax.ukey(), false)
-	// Get entire range covered by compaction.
-	amin, amax := append(t0, t1...).getRange(c.s.icmp)
-
-	// See if we can grow the number of inputs in "level" without
-	// changing the number of "level+1" files we pick up.
-	if len(t1) > 0 {
-		exp0 := vt0.getOverlaps(nil, c.s.icmp, amin.ukey(), amax.ukey(), c.level == 0)
-		if len(exp0) > len(t0) && t1.size()+exp0.size() < limit {
-			xmin, xmax := exp0.getRange(c.s.icmp)
-			exp1 := vt1.getOverlaps(nil, c.s.icmp, xmin.ukey(), xmax.ukey(), false)
-			if len(exp1) == len(t1) {
-				c.s.logf("table@compaction expanding L%d+L%d (F·%d S·%s)+(F·%d S·%s) -> (F·%d S·%s)+(F·%d S·%s)",
-					c.level, c.level+1, len(t0), shortenb(int(t0.size())), len(t1), shortenb(int(t1.size())),
-					len(exp0), shortenb(int(exp0.size())), len(exp1), shortenb(int(exp1.size())))
-				imin, imax = xmin, xmax
-				t0, t1 = exp0, exp1
-				amin, amax = append(t0, t1...).getRange(c.s.icmp)
-			}
-		}
-	}
-
-	// Compute the set of grandparent files that overlap this compaction
-	// (parent == level+1; grandparent == level+2)
-	if c.level+2 < c.s.o.GetNumLevel() {
-		c.gp = c.v.tables[c.level+2].getOverlaps(c.gp, c.s.icmp, amin.ukey(), amax.ukey(), false)
-	}
-
-	c.tables[0], c.tables[1] = t0, t1
-	c.imin, c.imax = imin, imax
-}
-
-// Check whether compaction is trivial.
-func (c *compaction) trivial() bool {
-	return len(c.tables[0]) == 1 && len(c.tables[1]) == 0 && c.gp.size() <= c.maxGPOverlaps
-}
-
-func (c *compaction) baseLevelForKey(ukey []byte) bool {
-	for level, tables := range c.v.tables[c.level+2:] {
-		for c.tPtrs[level] < len(tables) {
-			t := tables[c.tPtrs[level]]
-			if c.s.icmp.uCompare(ukey, t.imax.ukey()) <= 0 {
-				// We've advanced far enough.
-				if c.s.icmp.uCompare(ukey, t.imin.ukey()) >= 0 {
-					// Key falls in this file's range, so definitely not base level.
-					return false
-				}
-				break
-			}
-			c.tPtrs[level]++
-		}
-	}
-	return true
-}
-
-func (c *compaction) shouldStopBefore(ikey iKey) bool {
-	for ; c.gpi < len(c.gp); c.gpi++ {
-		gp := c.gp[c.gpi]
-		if c.s.icmp.Compare(ikey, gp.imax) <= 0 {
-			break
-		}
-		if c.seenKey {
-			c.gpOverlappedBytes += gp.size
-		}
-	}
-	c.seenKey = true
-
-	if c.gpOverlappedBytes > c.maxGPOverlaps {
-		// Too much overlap for current output; start new output.
-		c.gpOverlappedBytes = 0
-		return true
-	}
-	return false
-}
-
-// Creates an iterator.
-func (c *compaction) newIterator() iterator.Iterator {
-	// Creates iterator slice.
-	icap := len(c.tables)
-	if c.level == 0 {
-		// Special case for level-0
-		icap = len(c.tables[0]) + 1
-	}
-	its := make([]iterator.Iterator, 0, icap)
-
-	// Options.
-	ro := &opt.ReadOptions{
-		DontFillCache: true,
-		Strict:        opt.StrictOverride,
-	}
-	strict := c.s.o.GetStrict(opt.StrictCompaction)
-	if strict {
-		ro.Strict |= opt.StrictReader
-	}
-
-	for i, tables := range c.tables {
-		if len(tables) == 0 {
-			continue
-		}
-
-		// Level-0 is not sorted and may overlaps each other.
-		if c.level+i == 0 {
-			for _, t := range tables {
-				its = append(its, c.s.tops.newIterator(t, nil, ro))
-			}
-		} else {
-			it := iterator.NewIndexedIterator(tables.newIndexIterator(c.s.tops, c.s.icmp, nil, ro), strict)
-			its = append(its, it)
-		}
-	}
-
-	return iterator.NewMergedIterator(its, c.s.icmp, strict)
-}
@@ -0,0 +1,287 @@
+// Copyright (c) 2012, Suryandaru Triandana <syndtr@gmail.com>
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package leveldb
+
+import (
+	"sync/atomic"
+
+	"github.com/syndtr/goleveldb/leveldb/iterator"
+	"github.com/syndtr/goleveldb/leveldb/memdb"
+	"github.com/syndtr/goleveldb/leveldb/opt"
+)
+
+func (s *session) pickMemdbLevel(umin, umax []byte) int {
+	v := s.version()
+	defer v.release()
+	return v.pickMemdbLevel(umin, umax)
+}
+
+func (s *session) flushMemdb(rec *sessionRecord, mdb *memdb.DB, level int) (level_ int, err error) {
+	// Create sorted table.
+	iter := mdb.NewIterator(nil)
+	defer iter.Release()
+	t, n, err := s.tops.createFrom(iter)
+	if err != nil {
+		return level, err
+	}
+
+	// Pick level and add to record.
+	if level < 0 {
+		level = s.pickMemdbLevel(t.imin.ukey(), t.imax.ukey())
+	}
+	rec.addTableFile(level, t)
+
+	s.logf("memdb@flush created L%d@%d N·%d S·%s %q:%q", level, t.file.Num(), n, shortenb(int(t.size)), t.imin, t.imax)
+	return level, nil
+}
+
+// Pick a compaction based on current state; need external synchronization.
+func (s *session) pickCompaction() *compaction {
+	v := s.version()
+
+	var level int
+	var t0 tFiles
+	if v.cScore >= 1 {
+		level = v.cLevel
+		cptr := s.stCompPtrs[level]
+		tables := v.tables[level]
+		for _, t := range tables {
+			if cptr == nil || s.icmp.Compare(t.imax, cptr) > 0 {
+				t0 = append(t0, t)
+				break
+			}
+		}
+		if len(t0) == 0 {
+			t0 = append(t0, tables[0])
+		}
+	} else {
+		if p := atomic.LoadPointer(&v.cSeek); p != nil {
+			ts := (*tSet)(p)
+			level = ts.level
+			t0 = append(t0, ts.table)
+		} else {
+			v.release()
+			return nil
+		}
+	}
+
+	return newCompaction(s, v, level, t0)
+}
+
+// Create compaction from given level and range; need external synchronization.
+func (s *session) getCompactionRange(level int, umin, umax []byte) *compaction {
+	v := s.version()
+
+	t0 := v.tables[level].getOverlaps(nil, s.icmp, umin, umax, level == 0)
+	if len(t0) == 0 {
+		v.release()
+		return nil
+	}
+
+	// Avoid compacting too much in one shot in case the range is large.
+	// But we cannot do this for level-0 since level-0 files can overlap
+	// and we must not pick one file and drop another older file if the
+	// two files overlap.
+	if level > 0 {
+		limit := uint64(v.s.o.GetCompactionSourceLimit(level))
+		total := uint64(0)
+		for i, t := range t0 {
+			total += t.size
+			if total >= limit {
+				s.logf("table@compaction limiting F·%d -> F·%d", len(t0), i+1)
+				t0 = t0[:i+1]
+				break
+			}
+		}
+	}
+
+	return newCompaction(s, v, level, t0)
+}
+
+func newCompaction(s *session, v *version, level int, t0 tFiles) *compaction {
+	c := &compaction{
+		s:             s,
+		v:             v,
+		level:         level,
+		tables:        [2]tFiles{t0, nil},
+		maxGPOverlaps: uint64(s.o.GetCompactionGPOverlaps(level)),
+		tPtrs:         make([]int, s.o.GetNumLevel()),
+	}
+	c.expand()
+	c.save()
+	return c
+}
+
+// compaction represent a compaction state.
+type compaction struct {
+	s *session
+	v *version
+
+	level         int
+	tables        [2]tFiles
+	maxGPOverlaps uint64
+
+	gp                tFiles
+	gpi               int
+	seenKey           bool
+	gpOverlappedBytes uint64
+	imin, imax        iKey
+	tPtrs             []int
+	released          bool
+
+	snapGPI               int
+	snapSeenKey           bool
+	snapGPOverlappedBytes uint64
+	snapTPtrs             []int
+}
+
+func (c *compaction) save() {
+	c.snapGPI = c.gpi
+	c.snapSeenKey = c.seenKey
+	c.snapGPOverlappedBytes = c.gpOverlappedBytes
+	c.snapTPtrs = append(c.snapTPtrs[:0], c.tPtrs...)
+}
+
+func (c *compaction) restore() {
+	c.gpi = c.snapGPI
+	c.seenKey = c.snapSeenKey
+	c.gpOverlappedBytes = c.snapGPOverlappedBytes
+	c.tPtrs = append(c.tPtrs[:0], c.snapTPtrs...)
+}
+
+func (c *compaction) release() {
+	if !c.released {
+		c.released = true
+		c.v.release()
+	}
+}
+
+// Expand compacted tables; need external synchronization.
+func (c *compaction) expand() {
+	limit := uint64(c.s.o.GetCompactionExpandLimit(c.level))
+	vt0, vt1 := c.v.tables[c.level], c.v.tables[c.level+1]
+
+	t0, t1 := c.tables[0], c.tables[1]
+	imin, imax := t0.getRange(c.s.icmp)
+	// We expand t0 here just incase ukey hop across tables.
+	t0 = vt0.getOverlaps(t0, c.s.icmp, imin.ukey(), imax.ukey(), c.level == 0)
+	if len(t0) != len(c.tables[0]) {
+		imin, imax = t0.getRange(c.s.icmp)
+	}
+	t1 = vt1.getOverlaps(t1, c.s.icmp, imin.ukey(), imax.ukey(), false)
+	// Get entire range covered by compaction.
+	amin, amax := append(t0, t1...).getRange(c.s.icmp)
+
+	// See if we can grow the number of inputs in "level" without
+	// changing the number of "level+1" files we pick up.
+	if len(t1) > 0 {
+		exp0 := vt0.getOverlaps(nil, c.s.icmp, amin.ukey(), amax.ukey(), c.level == 0)
+		if len(exp0) > len(t0) && t1.size()+exp0.size() < limit {
+			xmin, xmax := exp0.getRange(c.s.icmp)
+			exp1 := vt1.getOverlaps(nil, c.s.icmp, xmin.ukey(), xmax.ukey(), false)
+			if len(exp1) == len(t1) {
+				c.s.logf("table@compaction expanding L%d+L%d (F·%d S·%s)+(F·%d S·%s) -> (F·%d S·%s)+(F·%d S·%s)",
+					c.level, c.level+1, len(t0), shortenb(int(t0.size())), len(t1), shortenb(int(t1.size())),
+					len(exp0), shortenb(int(exp0.size())), len(exp1), shortenb(int(exp1.size())))
+				imin, imax = xmin, xmax
+				t0, t1 = exp0, exp1
+				amin, amax = append(t0, t1...).getRange(c.s.icmp)
+			}
+		}
+	}
+
+	// Compute the set of grandparent files that overlap this compaction
+	// (parent == level+1; grandparent == level+2)
+	if c.level+2 < c.s.o.GetNumLevel() {
+		c.gp = c.v.tables[c.level+2].getOverlaps(c.gp, c.s.icmp, amin.ukey(), amax.ukey(), false)
+	}
+
+	c.tables[0], c.tables[1] = t0, t1
+	c.imin, c.imax = imin, imax
+}
+
+// Check whether compaction is trivial.
+func (c *compaction) trivial() bool {
+	return len(c.tables[0]) == 1 && len(c.tables[1]) == 0 && c.gp.size() <= c.maxGPOverlaps
+}
+
+func (c *compaction) baseLevelForKey(ukey []byte) bool {
+	for level, tables := range c.v.tables[c.level+2:] {
+		for c.tPtrs[level] < len(tables) {
+			t := tables[c.tPtrs[level]]
+			if c.s.icmp.uCompare(ukey, t.imax.ukey()) <= 0 {
+				// We've advanced far enough.
+				if c.s.icmp.uCompare(ukey, t.imin.ukey()) >= 0 {
+					// Key falls in this file's range, so definitely not base level.
+					return false
+				}
+				break
+			}
+			c.tPtrs[level]++
+		}
+	}
+	return true
+}
+
+func (c *compaction) shouldStopBefore(ikey iKey) bool {
+	for ; c.gpi < len(c.gp); c.gpi++ {
+		gp := c.gp[c.gpi]
+		if c.s.icmp.Compare(ikey, gp.imax) <= 0 {
+			break
+		}
+		if c.seenKey {
+			c.gpOverlappedBytes += gp.size
+		}
+	}
+	c.seenKey = true
+
+	if c.gpOverlappedBytes > c.maxGPOverlaps {
+		// Too much overlap for current output; start new output.
+		c.gpOverlappedBytes = 0
+		return true
+	}
+	return false
+}
+
+// Creates an iterator.
+func (c *compaction) newIterator() iterator.Iterator {
+	// Creates iterator slice.
+	icap := len(c.tables)
+	if c.level == 0 {
+		// Special case for level-0.
+		icap = len(c.tables[0]) + 1
+	}
+	its := make([]iterator.Iterator, 0, icap)
+
+	// Options.
+	ro := &opt.ReadOptions{
+		DontFillCache: true,
+		Strict:        opt.StrictOverride,
+	}
+	strict := c.s.o.GetStrict(opt.StrictCompaction)
+	if strict {
+		ro.Strict |= opt.StrictReader
+	}
+
+	for i, tables := range c.tables {
+		if len(tables) == 0 {
+			continue
+		}
+
+		// Level-0 is not sorted and may overlaps each other.
+		if c.level+i == 0 {
+			for _, t := range tables {
+				its = append(its, c.s.tops.newIterator(t, nil, ro))
+			}
+		} else {
+			it := iterator.NewIndexedIterator(tables.newIndexIterator(c.s.tops, c.s.icmp, nil, ro), strict)
+			its = append(its, it)
+		}
+	}
+
+	return iterator.NewMergedIterator(its, c.s.icmp, strict)
+}
@@ -52,8 +52,6 @@ type dtRecord struct {
 }

 type sessionRecord struct {
-	numLevel int
-
 	hasRec         int
 	comparer       string
 	journalNum     uint64
@@ -230,7 +228,7 @@ func (p *sessionRecord) readBytes(field string, r byteReader) []byte {
 	return x
 }

-func (p *sessionRecord) readLevel(field string, r io.ByteReader) int {
+func (p *sessionRecord) readLevel(field string, r io.ByteReader, numLevel int) int {
 	if p.err != nil {
 		return 0
 	}
@@ -238,14 +236,14 @@ func (p *sessionRecord) readLevel(field string, r io.ByteReader) int {
 	if p.err != nil {
 		return 0
 	}
-	if x >= uint64(p.numLevel) {
+	if x >= uint64(numLevel) {
 		p.err = errors.NewErrCorrupted(nil, &ErrManifestCorrupted{field, "invalid level number"})
 		return 0
 	}
 	return int(x)
 }

-func (p *sessionRecord) decode(r io.Reader) error {
+func (p *sessionRecord) decode(r io.Reader, numLevel int) error {
 	br, ok := r.(byteReader)
 	if !ok {
 		br = bufio.NewReader(r)
@@ -286,13 +284,13 @@ func (p *sessionRecord) decode(r io.Reader) error {
 				p.setSeqNum(x)
 			}
 		case recCompPtr:
-			level := p.readLevel("comp-ptr.level", br)
+			level := p.readLevel("comp-ptr.level", br, numLevel)
 			ikey := p.readBytes("comp-ptr.ikey", br)
 			if p.err == nil {
 				p.addCompPtr(level, iKey(ikey))
 			}
 		case recAddTable:
-			level := p.readLevel("add-table.level", br)
+			level := p.readLevel("add-table.level", br, numLevel)
 			num := p.readUvarint("add-table.num", br)
 			size := p.readUvarint("add-table.size", br)
 			imin := p.readBytes("add-table.imin", br)
@@ -301,7 +299,7 @@ func (p *sessionRecord) decode(r io.Reader) error {
 				p.addTable(level, num, size, imin, imax)
 			}
 		case recDelTable:
-			level := p.readLevel("del-table.level", br)
+			level := p.readLevel("del-table.level", br, numLevel)
 			num := p.readUvarint("del-table.num", br)
 			if p.err == nil {
 				p.delTable(level, num)
@@ -19,8 +19,8 @@ func decodeEncode(v *sessionRecord) (res bool, err error) {
 	if err != nil {
 		return
 	}
-	v2 := &sessionRecord{numLevel: opt.DefaultNumLevel}
-	err = v.decode(b)
+	v2 := &sessionRecord{}
+	err = v.decode(b, opt.DefaultNumLevel)
 	if err != nil {
 		return
 	}
@@ -34,7 +34,7 @@ func decodeEncode(v *sessionRecord) (res bool, err error) {

 func TestSessionRecord_EncodeDecode(t *testing.T) {
 	big := uint64(1) << 50
-	v := &sessionRecord{numLevel: opt.DefaultNumLevel}
+	v := &sessionRecord{}
 	i := uint64(0)
 	test := func() {
 		res, err := decodeEncode(v)
@@ -182,7 +182,7 @@ func (s *session) newManifest(rec *sessionRecord, v *version) (err error) {
 		defer v.release()
 	}
 	if rec == nil {
-		rec = &sessionRecord{numLevel: s.o.GetNumLevel()}
+		rec = &sessionRecord{}
 	}
 	s.fillRecord(rec, true)
 	v.fillRecord(rec)
@@ -240,9 +240,11 @@ func (s *session) flushManifest(rec *sessionRecord) (err error) {
 	if err != nil {
 		return
 	}
-	err = s.manifestWriter.Sync()
-	if err != nil {
-		return
+	if !s.o.GetNoSync() {
+		err = s.manifestWriter.Sync()
+		if err != nil {
+			return
+		}
 	}
 	s.recordCommited(rec)
 	return
@@ -243,7 +243,10 @@ func (fs *fileStorage) GetManifest() (f File, err error) {
 					rem = append(rem, fn)
 				}
 				if !pend1 || cerr == nil {
-					cerr = fmt.Errorf("leveldb/storage: corrupted or incomplete %s file", fn)
+					cerr = &ErrCorrupted{
+						File: fsParseName(filepath.Base(fn)),
+						Err:  errors.New("leveldb/storage: corrupted or incomplete manifest file"),
+					}
 				}
 			} else if f != nil && f1.Num() < f.Num() {
 				fs.log(fmt.Sprintf("skipping %s: obsolete", fn))
@@ -326,8 +329,7 @@ func (fs *fileStorage) Close() error {
 	runtime.SetFinalizer(fs, nil)

 	if fs.open > 0 {
-		fs.log(fmt.Sprintf("refuse to close, %d files still open", fs.open))
-		return fmt.Errorf("leveldb/storage: cannot close, %d files still open", fs.open)
+		fs.log(fmt.Sprintf("close: warning, %d files still open", fs.open))
 	}
 	fs.open = -1
 	e1 := fs.logw.Close()
@@ -505,30 +507,37 @@ func (f *file) path() string {
 	return filepath.Join(f.fs.path, f.name())
 }

-func (f *file) parse(name string) bool {
-	var num uint64
+func fsParseName(name string) *FileInfo {
+	fi := &FileInfo{}
 	var tail string
-	_, err := fmt.Sscanf(name, "%d.%s", &num, &tail)
+	_, err := fmt.Sscanf(name, "%d.%s", &fi.Num, &tail)
 	if err == nil {
 		switch tail {
 		case "log":
-			f.t = TypeJournal
+			fi.Type = TypeJournal
 		case "ldb", "sst":
-			f.t = TypeTable
+			fi.Type = TypeTable
 		case "tmp":
-			f.t = TypeTemp
+			fi.Type = TypeTemp
 		default:
-			return false
+			return nil
 		}
-		f.num = num
-		return true
+		return fi
 	}
-	n, _ := fmt.Sscanf(name, "MANIFEST-%d%s", &num, &tail)
+	n, _ := fmt.Sscanf(name, "MANIFEST-%d%s", &fi.Num, &tail)
 	if n == 1 {
-		f.t = TypeManifest
-		f.num = num
-		return true
+		fi.Type = TypeManifest
+		return fi
 	}
+	return nil
+}

-	return false
+func (f *file) parse(name string) bool {
+	fi := fsParseName(name)
+	if fi == nil {
+		return false
+	}
+	f.t = fi.Type
+	f.num = fi.Num
+	return true
 }
@@ -50,13 +50,23 @@ func rename(oldpath, newpath string) error {
 	return os.Rename(oldpath, newpath)
 }

+func isErrInvalid(err error) bool {
+	if err == os.ErrInvalid {
+		return true
+	}
+	if syserr, ok := err.(*os.SyscallError); ok && syserr.Err == syscall.EINVAL {
+		return true
+	}
+	return false
+}
+
 func syncDir(name string) error {
 	f, err := os.Open(name)
 	if err != nil {
 		return err
 	}
 	defer f.Close()
-	if err := f.Sync(); err != nil {
+	if err := f.Sync(); err != nil && !isErrInvalid(err) {
 		return err
 	}
 	return nil
@@ -46,6 +46,22 @@ var (
 	ErrClosed      = errors.New("leveldb/storage: closed")
 )

+// ErrCorrupted is the type that wraps errors that indicate corruption of
+// a file. Package storage has its own type instead of using
+// errors.ErrCorrupted to prevent circular import.
+type ErrCorrupted struct {
+	File *FileInfo
+	Err  error
+}
+
+func (e *ErrCorrupted) Error() string {
+	if e.File != nil {
+		return fmt.Sprintf("%v [file=%v]", e.Err, e.File)
+	} else {
+		return e.Err.Error()
+	}
+}
+
 // Syncer is the interface that wraps basic Sync method.
 type Syncer interface {
 	// Sync commits the current contents of the file to stable storage.
@@ -42,6 +42,8 @@ type tsOp uint
 const (
 	tsOpOpen tsOp = iota
 	tsOpCreate
+	tsOpReplace
+	tsOpRemove
 	tsOpRead
 	tsOpReadAt
 	tsOpWrite
@@ -241,6 +243,10 @@ func (tf tsFile) Replace(newfile storage.File) (err error) {
 	if err != nil {
 		return
 	}
+	if tf.shouldErr(tsOpReplace) {
+		err = errors.New("leveldb.testStorage: emulated create error")
+		return
+	}
 	err = tf.File.Replace(newfile.(tsFile).File)
 	if err != nil {
 		ts.t.Errorf("E: cannot replace file, num=%d type=%v: %v", tf.Num(), tf.Type(), err)
@@ -258,6 +264,10 @@ func (tf tsFile) Remove() (err error) {
 	if err != nil {
 		return
 	}
+	if tf.shouldErr(tsOpRemove) {
+		err = errors.New("leveldb.testStorage: emulated create error")
+		return
+	}
 	err = tf.File.Remove()
 	if err != nil {
 		ts.t.Errorf("E: cannot remove file, num=%d type=%v: %v", tf.Num(), tf.Type(), err)
@@ -287,6 +287,7 @@ func (x *tFilesSortByNum) Less(i, j int) bool {
 // Table operations.
 type tOps struct {
 	s      *session
+	noSync bool
 	cache  *cache.Cache
 	bcache *cache.Cache
 	bpool  *util.BufferPool
@@ -441,22 +442,27 @@ func newTableOps(s *session) *tOps {
 	var (
 		cacher cache.Cacher
 		bcache *cache.Cache
+		bpool  *util.BufferPool
 	)
 	if s.o.GetOpenFilesCacheCapacity() > 0 {
 		cacher = cache.NewLRU(s.o.GetOpenFilesCacheCapacity())
 	}
-	if !s.o.DisableBlockCache {
+	if !s.o.GetDisableBlockCache() {
 		var bcacher cache.Cacher
 		if s.o.GetBlockCacheCapacity() > 0 {
 			bcacher = cache.NewLRU(s.o.GetBlockCacheCapacity())
 		}
 		bcache = cache.NewCache(bcacher)
 	}
+	if !s.o.GetDisableBufferPool() {
+		bpool = util.NewBufferPool(s.o.GetBlockSize() + 5)
+	}
 	return &tOps{
 		s:      s,
+		noSync: s.o.GetNoSync(),
 		cache:  cache.NewCache(cacher),
 		bcache: bcache,
-		bpool:  util.NewBufferPool(s.o.GetBlockSize() + 5),
+		bpool:  bpool,
 	}
 }

@@ -501,9 +507,11 @@ func (w *tWriter) finish() (f *tFile, err error) {
 	if err != nil {
 		return
 	}
-	err = w.w.Sync()
-	if err != nil {
-		return
+	if !w.t.noSync {
+		err = w.w.Sync()
+		if err != nil {
+			return
+		}
 	}
 	f = newTableFile(w.file, uint64(w.tw.BytesLen()), iKey(w.first), iKey(w.last))
 	return
@@ -14,7 +14,7 @@ import (
 	"strings"
 	"sync"

-	"github.com/syndtr/gosnappy/snappy"
+	"github.com/golang/snappy"

 	"github.com/syndtr/goleveldb/leveldb/cache"
 	"github.com/syndtr/goleveldb/leveldb/comparer"
@@ -12,7 +12,7 @@ import (
 	"fmt"
 	"io"

-	"github.com/syndtr/gosnappy/snappy"
+	"github.com/golang/snappy"

 	"github.com/syndtr/goleveldb/leveldb/comparer"
 	"github.com/syndtr/goleveldb/leveldb/filter"
@@ -167,11 +167,7 @@ func (w *Writer) writeBlock(buf *util.Buffer, compression opt.Compression) (bh b
 		if n := snappy.MaxEncodedLen(buf.Len()) + blockTrailerLen; len(w.compressionScratch) < n {
 			w.compressionScratch = make([]byte, n)
 		}
-		var compressed []byte
-		compressed, err = snappy.Encode(w.compressionScratch, buf.Bytes())
-		if err != nil {
-			return
-		}
+		compressed := snappy.Encode(w.compressionScratch, buf.Bytes())
 		n := len(compressed)
 		b = compressed[:n+blockTrailerLen]
 		b[n] = blockTypeSnappyCompression
@@ -136,9 +136,8 @@ func (v *version) get(ikey iKey, ro *opt.ReadOptions, noValue bool) (value []byt
 		if !tseek {
 			if tset == nil {
 				tset = &tSet{level, t}
-			} else if tset.table.consumeSeek() <= 0 {
+			} else {
 				tseek = true
-				tcomp = atomic.CompareAndSwapPointer(&v.cSeek, nil, unsafe.Pointer(tset))
 			}
 		}

@@ -203,6 +202,28 @@ func (v *version) get(ikey iKey, ro *opt.ReadOptions, noValue bool) (value []byt
 		return true
 	})

+	if tseek && tset.table.consumeSeek() <= 0 {
+		tcomp = atomic.CompareAndSwapPointer(&v.cSeek, nil, unsafe.Pointer(tset))
+	}
+
+	return
+}
+
+func (v *version) sampleSeek(ikey iKey) (tcomp bool) {
+	var tset *tSet
+
+	v.walkOverlapping(ikey, func(level int, t *tFile) bool {
+		if tset == nil {
+			tset = &tSet{level, t}
+			return true
+		} else {
+			if tset.table.consumeSeek() <= 0 {
+				tcomp = atomic.CompareAndSwapPointer(&v.cSeek, nil, unsafe.Pointer(tset))
+			}
+			return false
+		}
+	}, nil)
+
 	return
 }

@@ -279,7 +300,7 @@ func (v *version) offsetOf(ikey iKey) (n uint64, err error) {
 	return
 }

-func (v *version) pickLevel(umin, umax []byte) (level int) {
+func (v *version) pickMemdbLevel(umin, umax []byte) (level int) {
 	if !v.tables[0].overlaps(v.s.icmp, umin, umax, true) {
 		var overlaps tFiles
 		maxLevel := v.s.o.GetMaxMemCompationLevel()
@@ -1,4 +1,4 @@
-Copyright (c) 2014 Barracuda Networks, Inc.
+Copyright (c) 2014-2015 Barracuda Networks, Inc.

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
@@ -36,6 +36,13 @@ to your Supervisor. Supervisors are also services, so you can create a
 tree structure here, depending on the exact combination of restarts
 you want to create.

+As a special case, when adding Supervisors to Supervisors, the "sub"
+supervisor will have the "super" supervisor's Log function copied.
+This allows you to set one log function on the "top" supervisor, and
+have it propagate down to all the sub-supervisors. This also allows
+libraries or modules to provide Supervisors without having to commit
+their users to a particular logging method.
+
 Finally, as what is probably the last line of your main() function, call
 .Serve() on your top level supervisor. This will start all the services
 you've defined.
@@ -126,8 +133,10 @@ type Supervisor struct {
 	// If you ever come up with some need to get into these, submit a pull
 	// request to make them public and some smidge of justification, and
 	// I'll happily do it.
-	logBadStop func(Service)
-	logFailure func(service Service, currentFailures float64, failureThreshold float64, restarting bool, error interface{}, stacktrace []byte)
+	// But since I've now changed the signature on these once, I'm glad I
+	// didn't start with them public... :)
+	logBadStop func(*Supervisor, Service)
+	logFailure func(supervisor *Supervisor, service Service, currentFailures float64, failureThreshold float64, restarting bool, error interface{}, stacktrace []byte)
 	logBackoff func(*Supervisor, bool)

 	// avoid a dependency on github.com/thejerf/abtime by just implementing
@@ -233,10 +242,10 @@ func New(name string, spec Spec) (s *Supervisor) {
 	s.resumeTimer = make(chan time.Time)

 	// set up the default logging handlers
-	s.logBadStop = func(service Service) {
-		s.log(fmt.Sprintf("Service %s failed to terminate in a timely manner", serviceName(service)))
+	s.logBadStop = func(supervisor *Supervisor, service Service) {
+		s.log(fmt.Sprintf("%s: Service %s failed to terminate in a timely manner", serviceName(supervisor), serviceName(service)))
 	}
-	s.logFailure = func(service Service, failures float64, threshold float64, restarting bool, err interface{}, st []byte) {
+	s.logFailure = func(supervisor *Supervisor, service Service, failures float64, threshold float64, restarting bool, err interface{}, st []byte) {
 		var errString string

 		e, canError := err.(error)
@@ -246,7 +255,7 @@ func New(name string, spec Spec) (s *Supervisor) {
 			errString = fmt.Sprintf("%#v", err)
 		}

-		s.log(fmt.Sprintf("Failed service '%s' (%f failures of %f), restarting: %#v, error: %s, stacktrace: %s", serviceName(service), failures, threshold, restarting, errString, string(st)))
+		s.log(fmt.Sprintf("%s: Failed service '%s' (%f failures of %f), restarting: %#v, error: %s, stacktrace: %s", serviceName(supervisor), serviceName(service), failures, threshold, restarting, errString, string(st)))
 	}
 	s.logBackoff = func(s *Supervisor, entering bool) {
 		if entering {
@@ -346,12 +355,24 @@ will be started when the supervisor is.

 The returned ServiceID may be passed to the Remove method of the Supervisor
 to terminate the service.
+
+As a special behavior, if the service added is itself a supervisor, the
+supervisor being added will copy the Log function from the Supervisor it
+is being added to. This allows factoring out providing a Supervisor
+from its logging.
+
 */
 func (s *Supervisor) Add(service Service) ServiceToken {
 	if s == nil {
 		panic("can't add service to nil *suture.Supervisor")
 	}

+	if supervisor, isSupervisor := service.(*Supervisor); isSupervisor {
+		supervisor.logBadStop = s.logBadStop
+		supervisor.logFailure = s.logFailure
+		supervisor.logBackoff = s.logBackoff
+	}
+
 	if s.state == notRunning {
 		id := s.serviceCounter
 		s.serviceCounter++
@@ -492,12 +513,12 @@ func (s *Supervisor) handleFailedService(id serviceID, err interface{}, stacktra
 	if monitored {
 		if s.state == normal {
 			s.runService(failedService, id)
-			s.logFailure(failedService, s.failures, s.failureThreshold, true, err, stacktrace)
+			s.logFailure(s, failedService, s.failures, s.failureThreshold, true, err, stacktrace)
 		} else {
 			// FIXME: When restarting, check that the service still
 			// exists (it may have been stopped in the meantime)
 			s.restartQueue = append(s.restartQueue, id)
-			s.logFailure(failedService, s.failures, s.failureThreshold, false, err, stacktrace)
+			s.logFailure(s, failedService, s.failures, s.failureThreshold, false, err, stacktrace)
 		}
 	}
 }
@@ -536,7 +557,7 @@ func (s *Supervisor) removeService(id serviceID) {
 			case <-successChan:
 				// Life is good!
 			case <-failChan:
-				s.logBadStop(service)
+				s.logBadStop(s, service)
 			}
 		}()
 	}
@@ -77,7 +77,7 @@ func TestFailures(t *testing.T) {
 		// to avoid deadlocks during shutdown, we have to not try to send
 		// things out on channels while we're shutting down (this undoes the
 		// logFailure overide about 25 lines down)
-		s.logFailure = func(Service, float64, float64, bool, interface{}, []byte) {}
+		s.logFailure = func(*Supervisor, Service, float64, float64, bool, interface{}, []byte) {}
 		s.Stop()
 	}()
 	s.sync()
@@ -102,7 +102,7 @@ func TestFailures(t *testing.T) {

 	failNotify := make(chan bool)
 	// use this to synchronize on here
-	s.logFailure = func(s Service, cf float64, ft float64, r bool, error interface{}, stacktrace []byte) {
+	s.logFailure = func(supervisor *Supervisor, s Service, cf float64, ft float64, r bool, error interface{}, stacktrace []byte) {
 		failNotify <- r
 	}

@@ -276,8 +276,8 @@ func TestDefaultLogging(t *testing.T) {

 	serviceName(&BarelyService{})

-	s.logBadStop(service)
-	s.logFailure(service, 1, 1, true, errors.New("test error"), []byte{})
+	s.logBadStop(s, service)
+	s.logFailure(s, service, 1, 1, true, errors.New("test error"), []byte{})

 	s.Stop()
 }
@@ -289,9 +289,17 @@ func TestNestedSupervisors(t *testing.T) {
 	super2 := NewSimple("Nested5")
 	service := NewService("Service5")

+	super2.logBadStop = func(*Supervisor, Service) {
+		panic("Failed to copy logBadStop")
+	}
+
 	super1.Add(super2)
 	super2.Add(service)

+	// test the functions got copied from super1; if this panics, it didn't
+	// get copied
+	super2.logBadStop(super2, service)
+
 	go super1.Serve()
 	super1.sync()

@@ -340,7 +348,7 @@ func TestStoppingStillWorksWithHungServices(t *testing.T) {
 		return resumeChan
 	}
 	failNotify := make(chan struct{})
-	s.logBadStop = func(s Service) {
+	s.logBadStop = func(supervisor *Supervisor, s Service) {
 		failNotify <- struct{}{}
 	}

@@ -438,7 +446,7 @@ func TestFailingSupervisors(t *testing.T) {
 	}
 	failNotify := make(chan string)
 	// use this to synchronize on here
-	s1.logFailure = func(s Service, cf float64, ft float64, r bool, error interface{}, stacktrace []byte) {
+	s1.logFailure = func(supervisor *Supervisor, s Service, cf float64, ft float64, r bool, error interface{}, stacktrace []byte) {
 		failNotify <- fmt.Sprintf("%s", s)
 	}

@@ -471,29 +471,22 @@ func computeNonStarterCounts() {
 		if exp := c.forms[FCompatibility].expandedDecomp; len(exp) > 0 {
 			runes = exp
 		}
+		// We consider runes that combine backwards to be non-starters for the
+		// purpose of Stream-Safe Text Processing.
 		for _, r := range runes {
-			if chars[r].ccc == 0 {
+			if cr := &chars[r]; cr.ccc == 0 && !cr.forms[FCompatibility].combinesBackward {
 				break
 			}
 			c.nLeadingNonStarters++
 		}
 		for i := len(runes) - 1; i >= 0; i-- {
-			if chars[runes[i]].ccc == 0 {
+			if cr := &chars[runes[i]]; cr.ccc == 0 && !cr.forms[FCompatibility].combinesBackward {
 				break
 			}
 			c.nTrailingNonStarters++
 		}
-
-		// We consider runes that combine backwards to be non-starters for the
-		// purpose of Stream-Safe Text Processing.
-		for _, f := range c.forms {
-			if c.ccc == 0 && f.combinesBackward {
-				if len(c.forms[FCompatibility].expandedDecomp) > 0 {
-					log.Fatalf("%U: CCC==0 modifier with an expansion is not supported.", i)
-				}
-				c.nTrailingNonStarters = 1
-				c.nLeadingNonStarters = 1
-			}
+		if c.nTrailingNonStarters > 3 {
+			log.Fatalf("%U: Decomposition with more than 3 (%d) trailing modifiers (%U)", i, c.nTrailingNonStarters, runes)
 		}

 		if isHangul(rune(i)) {
@@ -839,10 +832,16 @@ func verifyComputed() {
 				continue
 			}
 			if a, b := c.nLeadingNonStarters > 0, (c.ccc > 0 || f.combinesBackward); a != b {
-				// We accept these two runes to be treated differently (it only affects
-				// segment breaking in iteration, most likely on inproper use), but
+				// We accept these runes to be treated differently (it only affects
+				// segment breaking in iteration, most likely on improper use), but
 				// reconsider if more characters are added.
-				if i != 0xFF9E && i != 0xFF9F {
+				// U+FF9E HALFWIDTH KATAKANA VOICED SOUND MARK;Lm;0;L;<narrow> 3099;;;;N;;;;;
+				// U+FF9F HALFWIDTH KATAKANA SEMI-VOICED SOUND MARK;Lm;0;L;<narrow> 309A;;;;N;;;;;
+				// U+3133 HANGUL LETTER KIYEOK-SIOS;Lo;0;L;<compat> 11AA;;;;N;HANGUL LETTER GIYEOG SIOS;;;;
+				// U+318E HANGUL LETTER ARAEAE;Lo;0;L;<compat> 11A1;;;;N;HANGUL LETTER ALAE AE;;;;
+				// U+FFA3 HALFWIDTH HANGUL LETTER KIYEOK-SIOS;Lo;0;L;<narrow> 3133;;;;N;HALFWIDTH HANGUL LETTER GIYEOG SIOS;;;;
+				// U+FFDC HALFWIDTH HANGUL LETTER I;Lo;0;L;<narrow> 3163;;;;N;;;;;
+				if i != 0xFF9E && i != 0xFF9F && !(0x3133 <= i && i <= 0x318E) && !(0xFFA3 <= i && i <= 0xFFDC) {
 					log.Fatalf("%U: nLead was %v; want %v", i, a, b)
 				}
 			}
@@ -113,7 +113,25 @@ var decomposeSegmentTests = []PositionTest{
 	{"\u00C0b", 2, "A\u0300"},
 	// long
 	{grave(31), 60, grave(30) + cgj},
+	{"a" + grave(31), 61, "a" + grave(30) + cgj},
+
+	// Stability tests: see http://www.unicode.org/review/pr-29.html.
+	// U+0300 COMBINING GRAVE ACCENT;Mn;230;NSM;;;;;N;NON-SPACING GRAVE;;;;
+	// U+0B47 ORIYA VOWEL SIGN E;Mc;0;L;;;;;N;;;;;
+	// U+0B3E ORIYA VOWEL SIGN AA;Mc;0;L;;;;;N;;;;;
+	// U+1100 HANGUL CHOSEONG KIYEOK;Lo;0;L;;;;;N;;;;;
+	// U+1161 HANGUL JUNGSEONG A;Lo;0;L;;;;;N;;;;;
+	{"\u0B47\u0300\u0B3E", 8, "\u0B47\u0300\u0B3E"},
+	{"\u1100\u0300\u1161", 8, "\u1100\u0300\u1161"},
+	{"\u0B47\u0B3E", 6, "\u0B47\u0B3E"},
+	{"\u1100\u1161", 6, "\u1100\u1161"},
+
+	// U+04DA MALAYALAM VOWEL SIGN O;Mc;0;L;0D46 0D3E;;;;N;;;;;
+	// Sequence of decomposing characters that are starters and modifiers.
+	{"\u0d4a" + strings.Repeat("\u0d3e", 31), 90, "\u0d46" + strings.Repeat("\u0d3e", 30) + cgj},
+
 	{grave(30), 60, grave(30)},
+	// U+FF9E is a starter, but decomposes to U+3099, which is not.
 	{grave(30) + "\uff9e", 60, grave(30) + cgj},
 	// ends with incomplete UTF-8 encoding
 	{"\xCC", 0, ""},
@@ -552,6 +570,44 @@ var appendTestsNFC = []AppendTest{
 		"a" + rep(0x0305, maxNonStarters+4) + "\u0316",
 		"a" + rep(0x0305, maxNonStarters) + cgj + "\u0316" + rep(0x305, 4),
 	},
+
+	{ // Combine across non-blocking non-starters.
+		// U+0327 COMBINING CEDILLA;Mn;202;NSM;;;;;N;NON-SPACING CEDILLA;;;;
+		// U+0325 COMBINING RING BELOW;Mn;220;NSM;;;;;N;NON-SPACING RING BELOW;;;;
+		"", "a\u0327\u0325", "\u1e01\u0327",
+	},
+
+	{ // Jamo V+T does not combine.
+		"",
+		"\u1161\u11a8",
+		"\u1161\u11a8",
+	},
+
+	// Stability tests: see http://www.unicode.org/review/pr-29.html.
+	{"", "\u0b47\u0300\u0b3e", "\u0b47\u0300\u0b3e"},
+	{"", "\u1100\u0300\u1161", "\u1100\u0300\u1161"},
+	{"", "\u0b47\u0b3e", "\u0b4b"},
+	{"", "\u1100\u1161", "\uac00"},
+
+	// U+04DA MALAYALAM VOWEL SIGN O;Mc;0;L;0D46 0D3E;;;;N;;;;;
+	{ // 0d4a starts a new segment.
+		"",
+		"\u0d4a" + strings.Repeat("\u0d3e", 15) + "\u0d4a" + strings.Repeat("\u0d3e", 15),
+		"\u0d4a" + strings.Repeat("\u0d3e", 15) + "\u0d4a" + strings.Repeat("\u0d3e", 15),
+	},
+
+	{ // Split combining characters.
+		// TODO: don't insert CGJ before starters.
+		"",
+		"\u0d46" + strings.Repeat("\u0d3e", 31),
+		"\u0d4a" + strings.Repeat("\u0d3e", 29) + cgj + "\u0d3e",
+	},
+
+	{ // Split combining characters.
+		"",
+		"\u0d4a" + strings.Repeat("\u0d3e", 30),
+		"\u0d4a" + strings.Repeat("\u0d3e", 29) + cgj + "\u0d3e",
+	},
 }

 var appendTestsNFD = []AppendTest{
@@ -14,18 +14,24 @@ andrew-d	<andrew@du.nham.ca>
 asdil12		<dominik@heidler.eu>
 bencurthoys	<ben@bencurthoys.com>
 bigbear2nd	<bigbear2nd@gmail.com>
+brbecker	<brbecker@gmail.com>
 brendanlong	<self@brendanlong.com>
+brgmnn      <dan.arne.bergmann@gmail.com> <brgmnn@users.noreply.github.com>
 bsidhom		<bsidhom@gmail.com>
 calmh		<jakob@nym.se>
+canton7	<antony.male@gmail.com>
 cdata		<chris@scriptolo.gy>
 cdhowie	<me@chrishowie.com>
 ceh		<emil@hessman.se>
 cqcallaw	<enlightened.despot@gmail.com>
+dva	<denisva@gmail.com>
 dzarda		<dzardacz@gmail.com>
 facastagnini	<federico.castagnini@gmail.com>
 filoozoom	<philippe@schommers.be>
 frioux		<frew@afoolishmanifesto.com> <frioux@gmail.com>
+fti7	<frank@isemann.name>
 gillisig	<gilli@vx.is>
+hadogenes	<szafar@linux.pl>
 jarlebring	<jarlebring@gmail.com>
 jedie		<github.com@jensdiemer.de> <git@jensdiemer.de>
 jpjp		<jamespatterson@operamail.com> <jpjp@users.noreply.github.com>
@@ -35,8 +41,8 @@ kozec		<kozec@kozec.com>
 krozycki	<rozycki.karol@gmail.com>
 marcindziadus	<dziadus.marcin@gmail.com>
 marclaporte <marc@marclaporte.com>
-moshen		<moshen.colin@gmail.com>
 mogwa1	<devriesb@gmail.com>
+moshen		<moshen.colin@gmail.com>
 mvdan		<mvdan@mvdan.cc>
 pascalj		<github@pascalj.com> <mail@pascal-jungblut.com>
 peterhoeg	<peter@speartail.com>
@@ -44,9 +50,9 @@ philips		<brandon@ifup.org>
 piobpl		<piotrb10@gmail.com>
 pluby		<phill.luby@newredo.com>
 pyfisch		<pyfisch@gmail.com>
+qbit		<qbit@deftly.net>
 ralder		<ralder@yandex.ru>
 rumpelsepp	<stefan@sevenbyte.org>
-qbit		<qbit@deftly.net>
 sciurius	<jvromans@squirrel.nl>
 seehuhn		<voss@seehuhn.de>
 snnd		<dw@risu.io>
@@ -55,4 +61,5 @@ tnn2		<tnn@nygren.pp.se>
 tojrobinson	<tully@tojr.org>
 uok		<ueomkail@gmail.com> <uok@users.noreply.github.com>
 veeti		<veeti.paananen@rojekti.fi>
+wsgcsysadmin	<e.meitner@willystreet.coo>
 zukoo		<fxgsell@gmail.com>
@@ -36,6 +36,7 @@ var (
 	goos      string
 	noupgrade bool
 	version   string
+	goVersion float64
 	race      bool
 )

@@ -70,7 +71,7 @@ func main() {
 		log.Printf("Unknown goarch %q; proceed with caution!", goarch)
 	}

-	checkRequiredGoVersion()
+	goVersion, _ = checkRequiredGoVersion()

 	if flag.NArg() == 0 {
 		var tags []string
@@ -80,9 +81,9 @@ func main() {
 		install("./cmd/...", tags)

 		vet("./cmd/syncthing")
-		vet("./internal/...")
+		vet("./lib/...")
 		lint("./cmd/syncthing")
-		lint("./internal/...")
+		lint("./lib/...")
 		return
 	}

@@ -142,11 +143,11 @@ func main() {

 		case "vet":
 			vet("./cmd/syncthing")
-			vet("./internal/...")
+			vet("./lib/...")

 		case "lint":
 			lint("./cmd/syncthing")
-			lint("./internal/...")
+			lint("./lib/...")

 		default:
 			log.Fatalf("Unknown command %q", cmd)
@@ -154,7 +155,7 @@ func main() {
 	}
 }

-func checkRequiredGoVersion() {
+func checkRequiredGoVersion() (float64, bool) {
 	ver := run("go", "version")
 	re := regexp.MustCompile(`go version go(\d+\.\d+)`)
 	if m := re.FindSubmatch(ver); len(m) == 2 {
@@ -163,14 +164,16 @@ func checkRequiredGoVersion() {
 		f, err := strconv.ParseFloat(vs, 64)
 		if err != nil {
 			log.Printf("*** Couldn't parse Go version out of %q.\n*** This isn't known to work, proceed on your own risk.", vs)
-			return
+			return 0, false
 		}
 		if f < minGoVersion {
 			log.Fatalf("*** Go version %.01f is less than required %.01f.\n*** This is known not to work, not proceeding.", f, minGoVersion)
 		}
-	} else {
-		log.Printf("*** Unknown Go version %q.\n*** This isn't known to work, proceed on your own risk.", ver)
+		return f, true
 	}
+
+	log.Printf("*** Unknown Go version %q.\n*** This isn't known to work, proceed on your own risk.", ver)
+	return 0, false
 }

 func setup() {
@@ -178,6 +181,8 @@ func setup() {
 	runPrint("go", "get", "-v", "golang.org/x/tools/cmd/vet")
 	runPrint("go", "get", "-v", "golang.org/x/net/html")
 	runPrint("go", "get", "-v", "github.com/tools/godep")
+	runPrint("go", "get", "-v", "github.com/axw/gocov/gocov")
+	runPrint("go", "get", "-v", "github.com/AlekSi/gocov-xml")
 }

 func test(pkg string) {
@@ -314,6 +319,8 @@ func buildDeb() {
 		{src: "man/syncthing-rest-api.7", dst: "deb/usr/share/man/man7/syncthing-rest-api.7", perm: 0644},
 		{src: "man/syncthing-security.7", dst: "deb/usr/share/man/man7/syncthing-security.7", perm: 0644},
 		{src: "man/syncthing-versioning.7", dst: "deb/usr/share/man/man7/syncthing-versioning.7", perm: 0644},
+		{src: "etc/linux-systemd/system/syncthing@.service", dst: "deb/lib/systemd/system/syncthing@.service", perm: 0644},
+		{src: "etc/linux-systemd/user/syncthing.service", dst: "deb/usr/lib/systemd/user/syncthing.service", perm: 0644},
 	}

 	for _, file := range listFiles("extra") {
@@ -400,16 +407,16 @@ func setBuildEnv() {

 func assets() {
 	setBuildEnv()
-	runPipe("internal/auto/gui.files.go", "go", "run", "cmd/genassets/main.go", "gui")
+	runPipe("lib/auto/gui.files.go", "go", "run", "script/genassets.go", "gui")
 }

 func xdr() {
-	runPrint("go", "generate", "./internal/discover", "./internal/db")
+	runPrint("go", "generate", "./lib/discover", "./lib/db")
 }

 func translate() {
 	os.Chdir("gui/assets/lang")
-	runPipe("lang-en-new.json", "go", "run", "../../../cmd/translate/main.go", "lang-en.json", "../../index.html")
+	runPipe("lang-en-new.json", "go", "run", "../../../script/translate.go", "lang-en.json", "../../")
 	os.Remove("lang-en.json")
 	err := os.Rename("lang-en-new.json", "lang-en.json")
 	if err != nil {
@@ -420,7 +427,7 @@ func translate() {

 func transifex() {
 	os.Chdir("gui/assets/lang")
-	runPrint("go", "run", "../../../cmd/transifexdl/main.go")
+	runPrint("go", "run", "../../../script/transifexdl.go")
 	os.Chdir("../../..")
 	assets()
 }
@@ -436,13 +443,18 @@ func clean() {
 }

 func ldflags() string {
-	var b bytes.Buffer
+	sep := ' '
+	if goVersion > 1.4 {
+		sep = '='
+	}
+
+	b := new(bytes.Buffer)
 	b.WriteString("-w")
-	b.WriteString(fmt.Sprintf(" -X main.Version %s", version))
-	b.WriteString(fmt.Sprintf(" -X main.BuildStamp %d", buildStamp()))
-	b.WriteString(fmt.Sprintf(" -X main.BuildUser %s", buildUser()))
-	b.WriteString(fmt.Sprintf(" -X main.BuildHost %s", buildHost()))
-	b.WriteString(fmt.Sprintf(" -X main.BuildEnv %s", buildEnvironment()))
+	fmt.Fprintf(b, " -X main.Version%c%s", sep, version)
+	fmt.Fprintf(b, " -X main.BuildStamp%c%d", sep, buildStamp())
+	fmt.Fprintf(b, " -X main.BuildUser%c%s", sep, buildUser())
+	fmt.Fprintf(b, " -X main.BuildHost%c%s", sep, buildHost())
+	fmt.Fprintf(b, " -X main.BuildEnv%c%s", sep, buildEnvironment())
 	return b.String()
 }

@@ -740,7 +752,9 @@ func vet(pkg string) {
 		if falseAlarmComposites.Match(line) || exitStatus.Match(line) {
 			continue
 		}
-		log.Printf("%s", line)
+		if len(line) > 0 {
+			log.Printf("%s", line)
+		}
 	}
 }

@@ -756,6 +770,8 @@ func lint(pkg string) {
 		if analCommentPolicy.Match(line) {
 			continue
 		}
-		log.Printf("%s", line)
+		if len(line) > 0 {
+			log.Printf("%s", line)
+		}
 	}
 }
@@ -4,88 +4,97 @@ IFS=$'\n\t'

 STTRACE=${STTRACE:-}

+script() {
+	name="$1"
+	shift
+	go run "script/$name.go" "$@"
+}
+
+build() {
+	go run build.go "$@"
+}
+
 case "${1:-default}" in
 	default)
-		go run build.go
+		build
 		;;

 	clean)
-		go run build.go "$1"
-		;;
-
-	test)
-		ulimit -t 60 &>/dev/null || true
-		ulimit -d 512000 &>/dev/null || true
-		ulimit -m 512000 &>/dev/null || true
-		go run build.go test
-		;;
-
-	bench)
-		LOGGER_DISCARD=1 go run build.go bench | go run benchfilter.go
+		build "$@"
 		;;

 	tar)
-		go run build.go "$1"
+		build "$@"
 		;;

 	deps)
-		go run build.go "$1"
+		build "$@"
 		;;

 	assets)
-		go run build.go "$1"
+		build "$@"
 		;;

 	xdr)
-		go run build.go "$1"
+		build "$@"
 		;;

 	translate)
-		go run build.go "$1"
+		build "$@"
 		;;

-	prerelease)
-		go run build.go transifex
-		git add -A gui/assets/ internal/auto/
-		pushd man ; ./refresh.sh ; popd
-		git add -A man
-		echo
-		echo Changelog:
-		go run changelog.go
-		;;
-
-	noupgrade)
-		go run build.go -no-upgrade tar
-		;;
-
-	all)
-		go run build.go -goos darwin -goarch amd64 tar
-		go run build.go -goos darwin -goarch 386 tar
-
-		go run build.go -goos dragonfly -goarch 386 tar
-		go run build.go -goos dragonfly -goarch amd64 tar
-
-		go run build.go -goos freebsd -goarch 386 tar
-		go run build.go -goos freebsd -goarch amd64 tar
-
-		go run build.go -goos linux -goarch 386 tar
-		go run build.go -goos linux -goarch amd64 tar
-		go run build.go -goos linux -goarch arm tar
-
-		go run build.go -goos netbsd -goarch 386 tar
-		go run build.go -goos netbsd -goarch amd64 tar
-
-		go run build.go -goos openbsd -goarch 386 tar
-		go run build.go -goos openbsd -goarch amd64 tar
-
-		go run build.go -goos solaris -goarch amd64 tar
-
-		go run build.go -goos windows -goarch 386 zip
-		go run build.go -goos windows -goarch amd64 zip
+	deb)
+		build "$@"
 		;;

 	setup)
-		echo "Don't worry, just build."
+		build "$@"
+		;;
+
+	test)
+		ulimit -t 600 &>/dev/null || true
+		ulimit -d 512000 &>/dev/null || true
+		ulimit -m 512000 &>/dev/null || true
+		LOGGER_DISCARD=1 build test
+		;;
+
+	bench)
+		LOGGER_DISCARD=1 build bench | script benchfilter
+		;;
+
+	prerelease)
+		build transifex
+		git add -A gui/assets/ lib/auto/
+		pushd man ; ./refresh.sh ; popd
+		git add -A man
+		;;
+
+	noupgrade)
+		build -no-upgrade tar
+		;;
+
+	all)
+		build -goos darwin -goarch amd64 tar
+
+		build -goos dragonfly -goarch amd64 tar
+
+		build -goos freebsd -goarch 386 tar
+		build -goos freebsd -goarch amd64 tar
+
+		build -goos linux -goarch 386 tar
+		build -goos linux -goarch amd64 tar
+		build -goos linux -goarch arm tar
+
+		build -goos netbsd -goarch 386 tar
+		build -goos netbsd -goarch amd64 tar
+
+		build -goos openbsd -goarch 386 tar
+		build -goos openbsd -goarch amd64 tar
+
+		build -goos solaris -goarch amd64 tar
+
+		build -goos windows -goarch 386 zip
+		build -goos windows -goarch amd64 zip
 		;;

 	test-cov)
@@ -93,9 +102,6 @@ case "${1:-default}" in
 		ulimit -d 512000 &>/dev/null || true
 		ulimit -m 512000 &>/dev/null || true

-		go get github.com/axw/gocov/gocov
-		go get github.com/AlekSi/gocov-xml
-
 		echo "mode: set" > coverage.out
 		fail=0

@@ -121,11 +127,12 @@ case "${1:-default}" in
 		;;

 	docker-all)
+		img=${DOCKERIMG:-syncthing/build:latest}
 		docker run --rm -h syncthing-builder -u $(id -u) -t \
 			-v $(pwd):/go/src/github.com/syncthing/syncthing \
 			-w /go/src/github.com/syncthing/syncthing \
 			-e "STTRACE=$STTRACE" \
-			syncthing/build:latest \
+			"$img" \
 			sh -c './build.sh clean \
 				&& ./build.sh test-cov \
 				&& ./build.sh bench \
@@ -133,11 +140,12 @@ case "${1:-default}" in
 		;;

 	docker-test)
+		img=${DOCKERIMG:-syncthing/build:latest}
 		docker run --rm -h syncthing-builder -u $(id -u) -t \
 			-v $(pwd):/go/src/github.com/syncthing/syncthing \
 			-w /go/src/github.com/syncthing/syncthing \
 			-e "STTRACE=$STTRACE" \
-			syncthing/build:latest \
+			"$img" \
 			sh -euxc './build.sh clean \
 				&& go run build.go -race \
 				&& export GOPATH=$(pwd)/Godeps/_workspace:$GOPATH \
@@ -147,21 +155,23 @@ case "${1:-default}" in
 		;;

 	docker-lint)
+		img=${DOCKERIMG:-syncthing/build:latest}
 		docker run --rm -h syncthing-builder -u $(id -u) -t \
 			-v $(pwd):/go/src/github.com/syncthing/syncthing \
 			-w /go/src/github.com/syncthing/syncthing \
 			-e "STTRACE=$STTRACE" \
-			syncthing/build:latest \
+			"$img" \
 			sh -euxc 'go run build.go lint'
 		;;


 	docker-vet)
+		img=${DOCKERIMG:-syncthing/build:latest}
 		docker run --rm -h syncthing-builder -u $(id -u) -t \
 			-v $(pwd):/go/src/github.com/syncthing/syncthing \
 			-w /go/src/github.com/syncthing/syncthing \
 			-e "STTRACE=$STTRACE" \
-			syncthing/build:latest \
+			"$img" \
 			sh -euxc 'go run build.go vet'
 		;;

@@ -1,53 +0,0 @@
-#!/bin/bash
-
-missing-authors() {
-	for email in $(git log --format=%ae HEAD | sort | uniq) ; do
-		grep -q "$email" AUTHORS || echo $email
-	done
-}
-
-no-docs-typos() {
-	# Commits that are known to not change code
-	grep -v 63bd0136fb40a91efaa279cb4b4159d82e8e6904 |\
-	grep -v 4e2feb6fbc791bb8a2daf0ab8efb10775d66343e |\
-	grep -v f2459ef3319b2f060dbcdacd0c35a1788a94b8bd |\
-	grep -v b61f418bf2d1f7d5a9d7088a20a2a448e5e66801 |\
-	grep -v f0621207e3953711f9ab86d99724f1d0faac45b1 |\
-	grep -v f1120d7aa936c0658429edef0037792520b46334 |\
-	grep -v a9339d0627fff439879d157c75077f02c9fac61b |\
-	grep -v 254c63763a3ad42fd82259f1767db526cff94a14 |\
-	grep -v 4b76ec40c07078beaa2c5e250ed7d9bd6276a718 |\
-	grep -v ffc39dfbcb34eacc3ea12327a02b6e7741a2c207 |\
-	grep -v 32a76901a91ff0f663db6f0830e0aedec946e4d0 |\
-	grep -v af3288043a49bcc28f8ae3060852a09de552fe5f |\
-	grep -v 3626003f680bad3e63677982576d3a05421e88e9
-}
-
-print-missing-authors() {
-	for email in $(missing-authors) ; do
-		git log --author="$email" --format="%H %ae %s" | no-docs-typos
-	done
-}
-
-print-missing-copyright() {
-	find . -name \*.go | xargs egrep -L 'Copyright|automatically generated' | grep -v Godeps | grep -v internal/auto/
-}
-
-authors=$(print-missing-authors)
-if [[ ! -z $authors ]] ; then
-	echo '***'
-	echo Author emails not in AUTHORS:
-	echo $authors
-	echo '***'
-	exit 1
-fi
-
-copy=$(print-missing-copyright)
-if [[ ! -z $copy ]] ; then
-	echo ***
-	echo Files missing copyright notice:
-	echo $copy
-	echo ***
-	exit 1
-fi
-
@@ -16,7 +16,7 @@ import (
 	"os"
 	"path/filepath"

-	"github.com/syncthing/syncthing/internal/symlinks"
+	"github.com/syncthing/syncthing/lib/symlinks"
 )

 func main() {
@@ -13,7 +13,7 @@ import (
 	"path/filepath"

 	"github.com/syncthing/protocol"
-	"github.com/syncthing/syncthing/internal/scanner"
+	"github.com/syncthing/syncthing/lib/scanner"
 )

 func main() {
@@ -12,7 +12,7 @@ import (
 	"os"

 	"github.com/syncthing/protocol"
-	"github.com/syncthing/syncthing/internal/discover"
+	"github.com/syncthing/syncthing/lib/discover"
 )

 func main() {
@@ -14,7 +14,7 @@ import (
 	"os"

 	"github.com/syncthing/protocol"
-	"github.com/syncthing/syncthing/internal/db"
+	"github.com/syncthing/syncthing/lib/db"
 	"github.com/syndtr/goleveldb/leveldb"
 	"github.com/syndtr/goleveldb/leveldb/opt"
 )
@@ -0,0 +1,98 @@
+// Copyright (C) 2015 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"bytes"
+	"crypto/md5"
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	"time"
+)
+
+func getmd5(filePath string) ([]byte, error) {
+	var result []byte
+	file, err := os.Open(filePath)
+	if err != nil {
+		return result, err
+	}
+	defer file.Close()
+
+	hash := md5.New()
+	if _, err := io.Copy(hash, file); err != nil {
+		return result, err
+	}
+
+	return hash.Sum(result), nil
+}
+
+func main() {
+	period := flag.Duration("period", 200*time.Millisecond, "Sleep period between checks")
+	flag.Parse()
+
+	file := flag.Arg(0)
+
+	if file == "" {
+		fmt.Println("Expects a path as an argument")
+		return
+	}
+
+	exists := true
+	size := int64(0)
+	mtime := time.Time{}
+	hash := []byte{}
+
+	for {
+		time.Sleep(*period)
+
+		newExists := true
+		fi, err := os.Stat(file)
+		if err != nil && os.IsNotExist(err) {
+			newExists = false
+		} else if err != nil {
+			fmt.Println("stat:", err)
+			return
+		}
+
+		if newExists != exists {
+			exists = newExists
+			if !newExists {
+				fmt.Println(file, "does not exist")
+			} else {
+				fmt.Println(file, "appeared")
+			}
+		}
+
+		if !exists {
+			size = 0
+			mtime = time.Time{}
+			hash = []byte{}
+			continue
+		}
+
+		if fi.IsDir() {
+			fmt.Println(file, "is directory")
+			return
+		}
+		newSize := fi.Size()
+		newMtime := fi.ModTime()
+
+		newHash, err := getmd5(file)
+		if err != nil {
+			fmt.Println("getmd5:", err)
+		}
+
+		if newSize != size || newMtime != mtime || !bytes.Equal(newHash, hash) {
+			fmt.Println(file, "Size:", newSize, "Mtime:", newMtime, "Hash:", fmt.Sprintf("%x", newHash))
+			hash = newHash
+			size = newSize
+			mtime = newMtime
+		}
+	}
+}
@@ -10,7 +10,7 @@ import (
 	"encoding/json"
 	"io"

-	"github.com/syncthing/syncthing/internal/events"
+	"github.com/syncthing/syncthing/lib/events"
 )

 // The auditSvc subscribes to events and writes these in JSON format, one
@@ -12,7 +12,7 @@ import (
 	"testing"
 	"time"

-	"github.com/syncthing/syncthing/internal/events"
+	"github.com/syncthing/syncthing/lib/events"
 )

 func TestAuditService(t *testing.T) {
@@ -15,9 +15,9 @@ import (
 	"time"

 	"github.com/syncthing/protocol"
-	"github.com/syncthing/syncthing/internal/config"
-	"github.com/syncthing/syncthing/internal/events"
-	"github.com/syncthing/syncthing/internal/model"
+	"github.com/syncthing/syncthing/lib/config"
+	"github.com/syncthing/syncthing/lib/events"
+	"github.com/syncthing/syncthing/lib/model"
 	"github.com/thejerf/suture"
 )

@@ -177,10 +177,6 @@ next:
 				if debugNet {
 					l.Debugf("cipher suite: %04X in lan: %t", conn.ConnectionState().CipherSuite, !limit)
 				}
-				events.Default.Log(events.DeviceConnected, map[string]string{
-					"id":   remoteID.String(),
-					"addr": conn.RemoteAddr().String(),
-				})

 				s.model.AddConnection(conn, protoConn)
 				continue next
@@ -26,15 +26,15 @@ import (

 	"github.com/calmh/logger"
 	"github.com/syncthing/protocol"
-	"github.com/syncthing/syncthing/internal/auto"
-	"github.com/syncthing/syncthing/internal/config"
-	"github.com/syncthing/syncthing/internal/db"
-	"github.com/syncthing/syncthing/internal/discover"
-	"github.com/syncthing/syncthing/internal/events"
-	"github.com/syncthing/syncthing/internal/model"
-	"github.com/syncthing/syncthing/internal/osutil"
-	"github.com/syncthing/syncthing/internal/sync"
-	"github.com/syncthing/syncthing/internal/upgrade"
+	"github.com/syncthing/syncthing/lib/auto"
+	"github.com/syncthing/syncthing/lib/config"
+	"github.com/syncthing/syncthing/lib/db"
+	"github.com/syncthing/syncthing/lib/discover"
+	"github.com/syncthing/syncthing/lib/events"
+	"github.com/syncthing/syncthing/lib/model"
+	"github.com/syncthing/syncthing/lib/osutil"
+	"github.com/syncthing/syncthing/lib/sync"
+	"github.com/syncthing/syncthing/lib/upgrade"
 	"github.com/vitrun/qart/qr"
 	"golang.org/x/crypto/bcrypt"
 )
@@ -49,10 +49,10 @@ var (
 	guiErrors    = []guiError{}
 	guiErrorsMut = sync.NewMutex()
 	startTime    = time.Now()
-	eventSub     *events.BufferedSubscription
 )

 type apiSvc struct {
+	id              protocol.DeviceID
 	cfg             config.GUIConfiguration
 	assetDir        string
 	model           *model.Model
@@ -60,14 +60,17 @@ type apiSvc struct {
 	fss             *folderSummarySvc
 	stop            chan struct{}
 	systemConfigMut sync.Mutex
+	eventSub        *events.BufferedSubscription
 }

-func newAPISvc(cfg config.GUIConfiguration, assetDir string, m *model.Model) (*apiSvc, error) {
+func newAPISvc(id protocol.DeviceID, cfg config.GUIConfiguration, assetDir string, m *model.Model, eventSub *events.BufferedSubscription) (*apiSvc, error) {
 	svc := &apiSvc{
+		id:              id,
 		cfg:             cfg,
 		assetDir:        assetDir,
 		model:           m,
 		systemConfigMut: sync.NewMutex(),
+		eventSub:        eventSub,
 	}

 	var err error
@@ -125,9 +128,6 @@ func (s *apiSvc) Serve() {
 	s.stop = make(chan struct{})

 	l.AddHandler(logger.LevelWarn, s.showGuiError)
-	sub := events.Default.Subscribe(events.AllEvents)
-	eventSub = events.NewBufferedSubscription(sub, 1000)
-	defer events.Default.Unsubscribe(sub)

 	// The GET handlers
 	getRestMux := http.NewServeMux()
@@ -190,14 +190,14 @@ func (s *apiSvc) Serve() {

 	// Wrap everything in CSRF protection. The /rest prefix should be
 	// protected, other requests will grant cookies.
-	handler := csrfMiddleware("/rest", s.cfg.APIKey, mux)
+	handler := csrfMiddleware(s.id.String()[:5], "/rest", s.cfg.APIKey, mux)

-	// Add our version as a header to responses
-	handler = withVersionMiddleware(handler)
+	// Add our version and ID as a header to responses
+	handler = withDetailsMiddleware(s.id, handler)

 	// Wrap everything in basic auth, if user/password is set.
 	if len(s.cfg.User) > 0 && len(s.cfg.Password) > 0 {
-		handler = basicAuthAndSessionMiddleware(s.cfg, handler)
+		handler = basicAuthAndSessionMiddleware("sessionid-"+s.id.String()[:5], s.cfg, handler)
 	}

 	// Redirect to HTTPS if we are supposed to
@@ -336,9 +336,10 @@ func noCacheMiddleware(h http.Handler) http.Handler {
 	})
 }

-func withVersionMiddleware(h http.Handler) http.Handler {
+func withDetailsMiddleware(id protocol.DeviceID, h http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.Header().Set("X-Syncthing-Version", Version)
+		w.Header().Set("X-Syncthing-ID", id.String())
 		h.ServeHTTP(w, r)
 	})
 }
@@ -354,6 +355,7 @@ func (s *apiSvc) getSystemVersion(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json; charset=utf-8")
 	json.NewEncoder(w).Encode(map[string]string{
 		"version":     Version,
+		"codename":    Codename,
 		"longVersion": LongVersion,
 		"os":          runtime.GOOS,
 		"arch":        runtime.GOARCH,
@@ -427,7 +429,10 @@ func folderSummary(m *model.Model, folder string) map[string]interface{} {
 		res["error"] = err.Error()
 	}

-	res["version"] = m.CurrentLocalVersion(folder) + m.RemoteLocalVersion(folder)
+	lv, _ := m.CurrentLocalVersion(folder)
+	rv, _ := m.RemoteLocalVersion(folder)
+
+	res["version"] = lv + rv

 	ignorePatterns, _, _ := m.GetIgnores(folder)
 	res["ignorePatterns"] = false
@@ -572,21 +577,26 @@ func (s *apiSvc) postSystemRestart(w http.ResponseWriter, r *http.Request) {
 func (s *apiSvc) postSystemReset(w http.ResponseWriter, r *http.Request) {
 	var qs = r.URL.Query()
 	folder := qs.Get("folder")
-	var err error
-	if len(folder) == 0 {
-		err = resetDB()
-	} else {
-		err = s.model.ResetFolder(folder)
-	}
-	if err != nil {
-		http.Error(w, err.Error(), 500)
-		return
+
+	if len(folder) > 0 {
+		if _, ok := cfg.Folders()[folder]; !ok {
+			http.Error(w, "Invalid folder ID", 500)
+			return
+		}
 	}
+
 	if len(folder) == 0 {
+		// Reset all folders.
+		for folder := range cfg.Folders() {
+			s.model.ResetFolder(folder)
+		}
 		s.flushResponse(`{"ok": "resetting database"}`, w)
 	} else {
-		s.flushResponse(`{"ok": "resetting folder " + folder}`, w)
+		// Reset a specific folder, assuming it's supposed to exist.
+		s.model.ResetFolder(folder)
+		s.flushResponse(`{"ok": "resetting folder `+folder+`"}`, w)
 	}
+
 	go restart()
 }

@@ -743,7 +753,7 @@ func (s *apiSvc) getEvents(w http.ResponseWriter, r *http.Request) {
 	f := w.(http.Flusher)
 	f.Flush()

-	evs := eventSub.Since(since, nil)
+	evs := s.eventSub.Since(since, nil)
 	if 0 < limit && limit < len(evs) {
 		evs = evs[len(evs)-limit:]
 	}
@@ -946,6 +956,11 @@ func (s embeddedStatic) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		return
 	}

+	if r.Header.Get("If-Modified-Since") == auto.AssetsBuildDate {
+		w.WriteHeader(http.StatusNotModified)
+		return
+	}
+
 	mtype := s.mimeTypeForFile(file)
 	if len(mtype) != 0 {
 		w.Header().Set("Content-Type", mtype)
@@ -961,6 +976,7 @@ func (s embeddedStatic) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 	w.Header().Set("Content-Length", fmt.Sprintf("%d", len(bs)))
 	w.Header().Set("Last-Modified", auto.AssetsBuildDate)
+	w.Header().Set("Cache-Control", "public")

 	w.Write(bs)
 }
@@ -14,8 +14,8 @@ import (
 	"strings"
 	"time"

-	"github.com/syncthing/syncthing/internal/config"
-	"github.com/syncthing/syncthing/internal/sync"
+	"github.com/syncthing/syncthing/lib/config"
+	"github.com/syncthing/syncthing/lib/sync"
 	"golang.org/x/crypto/bcrypt"
 )

@@ -24,14 +24,15 @@ var (
 	sessionsMut = sync.NewMutex()
 )

-func basicAuthAndSessionMiddleware(cfg config.GUIConfiguration, next http.Handler) http.Handler {
+func basicAuthAndSessionMiddleware(cookieName string, cfg config.GUIConfiguration, next http.Handler) http.Handler {
+
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		if cfg.APIKey != "" && r.Header.Get("X-API-Key") == cfg.APIKey {
 			next.ServeHTTP(w, r)
 			return
 		}

-		cookie, err := r.Cookie("sessionid")
+		cookie, err := r.Cookie(cookieName)
 		if err == nil && cookie != nil {
 			sessionsMut.Lock()
 			_, ok := sessions[cookie.Value]
@@ -86,7 +87,7 @@ func basicAuthAndSessionMiddleware(cfg config.GUIConfiguration, next http.Handle
 		sessions[sessionid] = true
 		sessionsMut.Unlock()
 		http.SetCookie(w, &http.Cookie{
-			Name:   "sessionid",
+			Name:   cookieName,
 			Value:  sessionid,
 			MaxAge: 0,
 		})
@@ -12,10 +12,9 @@ import (
 	"net/http"
 	"os"
 	"strings"
-	"time"

-	"github.com/syncthing/syncthing/internal/osutil"
-	"github.com/syncthing/syncthing/internal/sync"
+	"github.com/syncthing/syncthing/lib/osutil"
+	"github.com/syncthing/syncthing/lib/sync"
 )

 var csrfTokens []string
@@ -24,7 +23,7 @@ var csrfMut = sync.NewMutex()
 // Check for CSRF token on /rest/ URLs. If a correct one is not given, reject
 // the request with 403. For / and /index.html, set a new CSRF cookie if none
 // is currently set.
-func csrfMiddleware(prefix, apiKey string, next http.Handler) http.Handler {
+func csrfMiddleware(unique, prefix, apiKey string, next http.Handler) http.Handler {
 	loadCsrfTokens()
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		// Allow requests carrying a valid API key
@@ -35,10 +34,10 @@ func csrfMiddleware(prefix, apiKey string, next http.Handler) http.Handler {

 		// Allow requests for the front page, and set a CSRF cookie if there isn't already a valid one.
 		if !strings.HasPrefix(r.URL.Path, prefix) {
-			cookie, err := r.Cookie("CSRF-Token")
+			cookie, err := r.Cookie("CSRF-Token-" + unique)
 			if err != nil || !validCsrfToken(cookie.Value) {
 				cookie = &http.Cookie{
-					Name:  "CSRF-Token",
+					Name:  "CSRF-Token-" + unique,
 					Value: newCsrfToken(),
 				}
 				http.SetCookie(w, cookie)
@@ -54,7 +53,7 @@ func csrfMiddleware(prefix, apiKey string, next http.Handler) http.Handler {
 		}

 		// Verify the CSRF token
-		token := r.Header.Get("X-CSRF-Token")
+		token := r.Header.Get("X-CSRF-Token-" + unique)
 		if !validCsrfToken(token) {
 			http.Error(w, "CSRF Error", 403)
 			return
@@ -91,28 +90,20 @@ func newCsrfToken() string {
 }

 func saveCsrfTokens() {
-	name := locations[locCsrfTokens]
-	tmp := fmt.Sprintf("%s.tmp.%d", name, time.Now().UnixNano())
+	// We're ignoring errors in here. It's not super critical and there's
+	// nothing relevant we can do about them anyway...

-	f, err := os.OpenFile(tmp, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0644)
+	name := locations[locCsrfTokens]
+	f, err := osutil.CreateAtomic(name, 0600)
 	if err != nil {
 		return
 	}
-	defer os.Remove(tmp)

 	for _, t := range csrfTokens {
-		_, err := fmt.Fprintln(f, t)
-		if err != nil {
-			return
-		}
+		fmt.Fprintln(f, t)
 	}

-	err = f.Close()
-	if err != nil {
-		return
-	}
-
-	osutil.Rename(tmp, name)
+	f.Close()
 }

 func loadCsrfTokens() {
@@ -13,7 +13,7 @@ import (
 	"strings"
 	"time"

-	"github.com/syncthing/syncthing/internal/osutil"
+	"github.com/syncthing/syncthing/lib/osutil"
 )

 type locationEnum string
@@ -31,6 +31,7 @@ const (
 	locCsrfTokens                 = "csrfTokens"
 	locPanicLog                   = "panicLog"
 	locAuditLog                   = "auditLog"
+	locGUIAssets                  = "GUIAssets"
 	locDefFolder                  = "defFolder"
 )

@@ -52,6 +53,7 @@ var locations = map[locationEnum]string{
 	locCsrfTokens:    "${config}/csrftokens.txt",
 	locPanicLog:      "${config}/panic-${timestamp}.log",
 	locAuditLog:      "${config}/audit-${timestamp}.log",
+	locGUIAssets:     "${config}/gui",
 	locDefFolder:     "${home}/Sync",
 }

@@ -28,14 +28,14 @@ import (
 	"github.com/calmh/logger"
 	"github.com/juju/ratelimit"
 	"github.com/syncthing/protocol"
-	"github.com/syncthing/syncthing/internal/config"
-	"github.com/syncthing/syncthing/internal/db"
-	"github.com/syncthing/syncthing/internal/discover"
-	"github.com/syncthing/syncthing/internal/events"
-	"github.com/syncthing/syncthing/internal/model"
-	"github.com/syncthing/syncthing/internal/osutil"
-	"github.com/syncthing/syncthing/internal/symlinks"
-	"github.com/syncthing/syncthing/internal/upgrade"
+	"github.com/syncthing/syncthing/lib/config"
+	"github.com/syncthing/syncthing/lib/db"
+	"github.com/syncthing/syncthing/lib/discover"
+	"github.com/syncthing/syncthing/lib/events"
+	"github.com/syncthing/syncthing/lib/model"
+	"github.com/syncthing/syncthing/lib/osutil"
+	"github.com/syncthing/syncthing/lib/symlinks"
+	"github.com/syncthing/syncthing/lib/upgrade"
 	"github.com/syndtr/goleveldb/leveldb"
 	"github.com/syndtr/goleveldb/leveldb/errors"
 	"github.com/syndtr/goleveldb/leveldb/opt"
@@ -45,6 +45,7 @@ import (

 var (
 	Version     = "unknown-dev"
+	Codename    = "Aluminium Ant"
 	BuildEnv    = "default"
 	BuildStamp  = "0"
 	BuildDate   time.Time
@@ -93,7 +94,7 @@ func init() {
 	BuildDate = time.Unix(int64(stamp), 0)

 	date := BuildDate.UTC().Format("2006-01-02 15:04:05 MST")
-	LongVersion = fmt.Sprintf("syncthing %s (%s %s-%s %s) %s@%s %s", Version, runtime.Version(), runtime.GOOS, runtime.GOARCH, BuildEnv, BuildUser, BuildHost, date)
+	LongVersion = fmt.Sprintf(`syncthing %s "%s" (%s %s-%s %s) %s@%s %s`, Version, Codename, runtime.Version(), runtime.GOOS, runtime.GOARCH, BuildEnv, BuildUser, BuildHost, date)

 	if os.Getenv("STTRACE") != "" {
 		logFlags = log.Ltime | log.Ldate | log.Lmicroseconds | log.Lshortfile
@@ -252,6 +253,10 @@ func main() {
 		l.Fatalln(err)
 	}

+	if guiAssets == "" {
+		guiAssets = locations[locGUIAssets]
+	}
+
 	if runtime.GOOS == "windows" {
 		if logFile == "" {
 			// Use the default log file location
@@ -443,11 +448,17 @@ func syncthingMain() {
 		mainSvc.Add(newVerboseSvc())
 	}

+	// Event subscription for the API; must start early to catch the early events.
+	apiSub := events.NewBufferedSubscription(events.Default.Subscribe(events.AllEvents), 1000)
+
 	if len(os.Getenv("GOMAXPROCS")) == 0 {
 		runtime.GOMAXPROCS(runtime.NumCPU())
 	}

-	events.Default.Log(events.Starting, map[string]string{"home": baseDirs["config"]})
+	// Attempt to increase the limit on number of open files to the maximum
+	// allowed, in case we have many peers. We don't really care enough to
+	// report the error if there is one.
+	osutil.MaximizeOpenFileLimit()

 	// Ensure that that we have a certificate and key.
 	cert, err := tls.LoadX509KeyPair(locations[locCertFile], locations[locKeyFile])
@@ -468,6 +479,13 @@ func syncthingMain() {
 	l.Infoln(LongVersion)
 	l.Infoln("My ID:", myID)

+	// Emit the Starting event, now that we know who we are.
+
+	events.Default.Log(events.Starting, map[string]string{
+		"home": baseDirs["config"],
+		"myID": myID.String(),
+	})
+
 	// Prepare to be able to save configuration

 	cfgFile := locations[locConfigFile]
@@ -553,6 +571,9 @@ func syncthingMain() {
 		symlinks.Supported = false
 	}

+	protocol.PingTimeout = time.Duration(opts.PingTimeoutS) * time.Second
+	protocol.PingIdleTime = time.Duration(opts.PingIdleTimeS) * time.Second
+
 	if opts.MaxSendKbps > 0 {
 		writeRateLimit = ratelimit.NewBucketWithRate(float64(1000*opts.MaxSendKbps), int64(5*1000*opts.MaxSendKbps))
 	}
@@ -571,9 +592,19 @@ func syncthingMain() {

 	dbFile := locations[locDatabase]
 	ldb, err := leveldb.OpenFile(dbFile, dbOpts())
-	if err != nil && errors.IsCorrupted(err) {
+	if leveldbIsCorrupted(err) {
 		ldb, err = leveldb.RecoverFile(dbFile, dbOpts())
 	}
+	if leveldbIsCorrupted(err) {
+		// The database is corrupted, and we've tried to recover it but it
+		// didn't work. At this point there isn't much to do beyond dropping
+		// the database and reindexing...
+		l.Infoln("Database corruption detected, unable to recover. Reinitializing...")
+		if err := resetDB(); err != nil {
+			l.Fatalln("Remove database:", err)
+		}
+		ldb, err = leveldb.OpenFile(dbFile, dbOpts())
+	}
 	if err != nil {
 		l.Fatalln("Cannot open database:", err, "- Is another copy of Syncthing already running?")
 	}
@@ -589,7 +620,6 @@ func syncthingMain() {

 	m := model.NewModel(cfg, myID, myName, "syncthing", Version, ldb)
 	cfg.Subscribe(m)
-	mainSvc.Add(m)

 	if t := os.Getenv("STDEADLOCKTIMEOUT"); len(t) > 0 {
 		it, err := strconv.Atoi(t)
@@ -614,17 +644,17 @@ func syncthingMain() {
 		// Routine to pull blocks from other devices to synchronize the local
 		// folder. Does not run when we are in read only (publish only) mode.
 		if folderCfg.ReadOnly {
-			l.Okf("Ready to synchronize %s (read only; no external updates accepted)", folderCfg.ID)
 			m.StartFolderRO(folderCfg.ID)
 		} else {
-			l.Okf("Ready to synchronize %s (read-write)", folderCfg.ID)
 			m.StartFolderRW(folderCfg.ID)
 		}
 	}

+	mainSvc.Add(m)
+
 	// GUI

-	setupGUI(mainSvc, cfg, m)
+	setupGUI(mainSvc, cfg, m, apiSub)

 	// The default port we announce, possibly modified by setupUPnP next.

@@ -656,7 +686,6 @@ func syncthingMain() {
 			log.Fatal(err)
 		}
 		pprof.StartCPUProfile(f)
-		defer pprof.StopCPUProfile()
 	}

 	for _, device := range cfg.Devices() {
@@ -700,7 +729,9 @@ func syncthingMain() {
 		}
 	}

-	events.Default.Log(events.StartupComplete, nil)
+	events.Default.Log(events.StartupComplete, map[string]string{
+		"myID": myID.String(),
+	})
 	go generatePingEvents()

 	cleanConfigDirectory()
@@ -710,6 +741,11 @@ func syncthingMain() {
 	mainSvc.Stop()

 	l.Okln("Exiting")
+
+	if cpuProfile {
+		pprof.StopCPUProfile()
+	}
+
 	os.Exit(code)
 }

@@ -764,7 +800,7 @@ func startAuditing(mainSvc *suture.Supervisor) {
 	l.Infoln("Audit log in", auditFile)
 }

-func setupGUI(mainSvc *suture.Supervisor, cfg *config.Wrapper, m *model.Model) {
+func setupGUI(mainSvc *suture.Supervisor, cfg *config.Wrapper, m *model.Model, apiSub *events.BufferedSubscription) {
 	opts := cfg.Options()
 	guiCfg := overrideGUIConfig(cfg.GUI(), guiAddress, guiAuthentication, guiAPIKey)

@@ -793,7 +829,7 @@ func setupGUI(mainSvc *suture.Supervisor, cfg *config.Wrapper, m *model.Model) {

 			urlShow := fmt.Sprintf("%s://%s/", proto, net.JoinHostPort(hostShow, strconv.Itoa(addr.Port)))
 			l.Infoln("Starting web GUI on", urlShow)
-			api, err := newAPISvc(guiCfg, guiAssets, m)
+			api, err := newAPISvc(myID, guiCfg, guiAssets, m, apiSub)
 			if err != nil {
 				l.Fatalln("Cannot start GUI:", err)
 			}
@@ -817,6 +853,7 @@ func defaultConfig(myName string) config.Configuration {
 			ID:              "default",
 			RawPath:         locations[locDefFolder],
 			RescanIntervalS: 60,
+			MinDiskFreePct:  1,
 			Devices:         []config.FolderDeviceConfiguration{{DeviceID: myID}},
 		},
 	}
@@ -1079,3 +1116,19 @@ func checkShortIDs(cfg *config.Wrapper) error {
 	}
 	return nil
 }
+
+// A "better" version of leveldb's errors.IsCorrupted.
+func leveldbIsCorrupted(err error) bool {
+	switch {
+	case err == nil:
+		return false
+
+	case errors.IsCorrupted(err):
+		return true
+
+	case strings.Contains(err.Error(), "corrupted"):
+		return true
+	}
+
+	return false
+}
@@ -11,9 +11,9 @@ import (
 	"testing"

 	"github.com/syncthing/protocol"
-	"github.com/syncthing/syncthing/internal/config"
-	"github.com/syncthing/syncthing/internal/db"
-	"github.com/syncthing/syncthing/internal/model"
+	"github.com/syncthing/syncthing/lib/config"
+	"github.com/syncthing/syncthing/lib/db"
+	"github.com/syncthing/syncthing/lib/model"

 	"github.com/syndtr/goleveldb/leveldb"
 	"github.com/syndtr/goleveldb/leveldb/storage"
@@ -17,8 +17,8 @@ import (
 	"syscall"
 	"time"

-	"github.com/syncthing/syncthing/internal/osutil"
-	"github.com/syncthing/syncthing/internal/sync"
+	"github.com/syncthing/syncthing/lib/osutil"
+	"github.com/syncthing/syncthing/lib/sync"
 )

 var (
@@ -146,9 +146,8 @@ func monitorMain() {
 						// binary as part of the upgrade process.
 						l.Infoln("Restarting monitor...")
 						os.Setenv("STNORESTART", "")
-						err := exec.Command(args[0], args[1:]...).Start()
-						if err != nil {
-							l.Warnln("restart:", err)
+						if err = restartMonitor(args); err != nil {
+							l.Warnln("Restart:", err)
 						}
 						return
 					}
@@ -182,7 +181,8 @@ func copyStderr(stderr io.Reader, dst io.Writer) {
 				}

 				l.Warnf("Panic detected, writing to \"%s\"", panicFd.Name())
-				l.Warnln("Please create an issue at https://github.com/syncthing/syncthing/issues/ with the panic log attached")
+				l.Warnln("Please check for existing issues with similar panic message at https://github.com/syncthing/syncthing/issues/")
+				l.Warnln("If no issue with similar panic message exists, please create a new issue with the panic log attached")

 				stdoutMut.Lock()
 				for _, line := range stdoutFirstLines {
@@ -226,3 +226,39 @@ func copyStdout(stdout io.Reader, dst io.Writer) {
 		dst.Write([]byte(line))
 	}
 }
+
+func restartMonitor(args []string) error {
+	if runtime.GOOS != "windows" {
+		// syscall.Exec is the cleanest way to restart on Unixes as it
+		// replaces the current process with the new one, keeping the pid and
+		// controlling terminal and so on
+		return restartMonitorUnix(args)
+	}
+
+	// but it isn't supported on Windows, so there we start a normal
+	// exec.Command and return.
+	return restartMonitorWindows(args)
+}
+
+func restartMonitorUnix(args []string) error {
+	if !strings.ContainsRune(args[0], os.PathSeparator) {
+		// The path to the binary doesn't contain a slash, so it should be
+		// found in $PATH.
+		binary, err := exec.LookPath(args[0])
+		if err != nil {
+			return err
+		}
+		args[0] = binary
+	}
+
+	return syscall.Exec(args[0], args, os.Environ())
+}
+
+func restartMonitorWindows(args []string) error {
+	cmd := exec.Command(args[0], args[1:]...)
+	// Retain the standard streams
+	cmd.Stderr = os.Stderr
+	cmd.Stdout = os.Stdout
+	cmd.Stdin = os.Stdin
+	return cmd.Start()
+}
@@ -9,9 +9,9 @@ package main
 import (
 	"time"

-	"github.com/syncthing/syncthing/internal/events"
-	"github.com/syncthing/syncthing/internal/model"
-	"github.com/syncthing/syncthing/internal/sync"
+	"github.com/syncthing/syncthing/lib/events"
+	"github.com/syncthing/syncthing/lib/model"
+	"github.com/syncthing/syncthing/lib/sync"
 	"github.com/thejerf/suture"
 )

@@ -102,7 +102,9 @@ func (l *DowngradingListener) Accept() (net.Conn, error) {
 	}

 	br := bufio.NewReader(conn)
+	conn.SetReadDeadline(time.Now().Add(1 * time.Second))
 	bs, err := br.Peek(1)
+	conn.SetReadDeadline(time.Time{})
 	if err != nil {
 		// We hit a read error here, but the Accept() call succeeded so we must not return an error.
 		// We return the connection as is and let whoever tries to use it deal with the error.
@@ -10,8 +10,8 @@ import (
 	"fmt"
 	"time"

-	"github.com/syncthing/syncthing/internal/config"
-	"github.com/syncthing/syncthing/internal/upnp"
+	"github.com/syncthing/syncthing/lib/config"
+	"github.com/syncthing/syncthing/lib/upnp"
 )

 // The UPnP service runs a loop for discovery of IGDs (Internet Gateway
@@ -17,8 +17,8 @@ import (
 	"runtime"
 	"time"

-	"github.com/syncthing/syncthing/internal/config"
-	"github.com/syncthing/syncthing/internal/model"
+	"github.com/syncthing/syncthing/lib/config"
+	"github.com/syncthing/syncthing/lib/model"
 	"github.com/thejerf/suture"
 )

@@ -9,7 +9,7 @@ package main
 import (
 	"fmt"

-	"github.com/syncthing/syncthing/internal/events"
+	"github.com/syncthing/syncthing/lib/events"
 )

 // The verbose logging service subscribes to events and prints these in
@@ -5,4 +5,4 @@ This directory contains configuration files for running syncthing under the
 systemd user service. For further documentation take a look at the [systemd
 section][1] on the Github Wiki.

-[1]: http://docs.syncthing.net/users/autostart.html?highlight=systemd 
+[1]: http://docs.syncthing.net/users/autostart.html#systemd 
@@ -4,9 +4,8 @@ background under Mac OS X.
 1. Install the `syncthing` binary in a directory called `bin` in your
    home directory.

- 2. Edit the `syncthing.plist` file in the two places that refer to your
-    home directory; that is, replace `/Users/jb` with your actual home
-    directory location.
+ 2. Edit the `syncthing.plist` by replacing `USERNAME` with your actual
+    username such as `jb`.

 3. Copy the `syncthing.plist` file to `~/Library/LaunchAgents`.

@@ -15,3 +14,6 @@ background under Mac OS X.

 You probably want to turn off "Start Browser" among the settings to
 avoid it opening a browser window on each login.
+
+Logs are in `~/Library/Logs/Syncthing.log` and, for crashes and exceptions,
+`~/Library/Logs/Syncthing-Error.log`.
@@ -1,5 +1,11 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<!--
+	Make sure the "syncthing" executable is located at ~/bin/syncthing.
+	Replace the string "USERNAME" in this file with your username, such as "jb".
+	Copy this file to ~/Library/LaunchAgents/syncthing.plist.
+	Execute "launchctl load ~/Library/LaunchAgents/syncthing.plist".
+-->
 <plist version="1.0">
 	<dict>
 		<key>Label</key>
@@ -7,13 +13,13 @@

 		<key>ProgramArguments</key>
 		<array>
-			<string>/Users/jb/bin/syncthing</string>
+			<string>/Users/USERNAME/bin/syncthing</string>
 		</array>

 		<key>EnvironmentVariables</key>
 		<dict>
 			<key>HOME</key>
-			<string>/Users/jb</string>
+			<string>/Users/USERNAME</string>
 			<key>STNORESTART</key>
 			<string>1</string>
 		</dict>
@@ -26,5 +32,11 @@

 		<key>ProcessType</key>
 		<string>Background</string>
+
+		<key>StandardOutPath</key>
+		<string>/Users/USERNAME/Library/Logs/Syncthing.log</string>
+
+		<key>StandardErrorPath</key>
+		<string>/Users/USERNAME/Library/Logs/Syncthing-Errors.log</string>
 	</dict>
 </plist>
@@ -67,7 +67,7 @@ identicon {
    top: 1px;
 }

-.panel-heading .glyphicon {
+.panel-heading .fa, .modal-header .fa {
    margin-right: 10px;
 }

@@ -245,7 +245,7 @@ ul.three-columns li, ul.two-columns li {

 /** Footer nav on small devices **/

-@media (max-width: 767px) {
+@media (max-width: 991px) {
    body {
        padding-bottom: 0;
    }
@@ -1,5 +1,5 @@
 {
-    "A negative number of days doesn't make sense.": "A negative number of days doesn't make sense.",
+    "A negative number of days doesn't make sense.": "Няма логика на зададен отрицателен брой дни.",
    "A new major version may not be compatible with previous versions.": "Нова основна версия, която може да не е съвмеситима с предишни версии.",
    "API Key": "API Ключ",
    "About": "За Програмата",
@@ -10,6 +10,8 @@
    "Add new folder?": "Добави нова папка?",
    "Address": "Адрес",
    "Addresses": "Адреси",
+    "Advanced": "Допълнителни",
+    "Advanced Configuration": "Допълнителни настройки",
    "All Data": "Всички данни",
    "Allow Anonymous Usage Reporting?": "Разреши анонимен доклад за ползване на програмата?",
    "Alphabetic": "Азбучен ред",
@@ -17,10 +19,11 @@
    "Anonymous Usage Reporting": "Анонимен Доклад",
    "Any devices configured on an introducer device will be added to this device as well.": "Устройства настроени на introducer компютъра също ще бъдат добавени към този компютър.",
    "Automatic upgrades": "Автоматични ъпдейти",
+    "Be careful!": "Внимавай!",
    "Bugs": "Бъгове",
    "CPU Utilization": "Натоварване на Процесора",
    "Changelog": "Сипъск с промени",
-    "Clean out after": "Clean out after",
+    "Clean out after": "Изчисти след",
    "Close": "Затвори",
    "Command": "Команда",
    "Comment, when used at the start of a line": "Коментар, използван в началото на реда",
@@ -30,6 +33,7 @@
    "Copied from original": "Копиран от оригинала",
    "Copyright © 2015 the following Contributors:": "Правата запазени © 2015 Сътрудници:",
    "Delete": "Изтрий",
+    "Deleted": "Изтрито",
    "Device ID": "Идентификатор на устройство",
    "Device Identification": "Идентификация на устройство",
    "Device Name": "Име на устройство",
@@ -45,20 +49,23 @@
    "Edit Folder": "Промени папка",
    "Editing": "Променяне",
    "Enable UPnP": "Включи UPnP",
-    "Enter comma separated \"ip:port\" addresses or \"dynamic\" to perform automatic discovery of the address.": "Въведи \"ip:port\" адреси разделени със запетая или \"dynamic\", за да извършиш автоматична връзка на адреси.",
+    "Enter comma separated  (\"tcp://ip:port\", \"tcp://host:port\") addresses or \"dynamic\" to perform automatic discovery of the address.": "Въведи адреси разделени със запетая (\"tcp://ip:port\", \"tcp://host:port\") или \"dynamic\", за да извършиш автоматична връзка на адреси.",
    "Enter ignore patterns, one per line.": "Добави шаблони за игнориране, по един на ред.",
    "Error": "Грешка",
    "External File Versioning": "Външно упраление на версиите",
+    "Failed Items": "Неуспешни",
    "File Pull Order": "По ред на дърпане",
    "File Versioning": "Файлови Версии",
    "File permission bits are ignored when looking for changes. Use on FAT file systems.": "Битовете за права за достъп са игнорирани, когато се проверява за промени. Използвай с файлови системи тип FAT.",
-    "Files are moved to .stversions folder when replaced or deleted by Syncthing.": "Files are moved to .stversions folder when replaced or deleted by Syncthing.",
+    "Files are moved to .stversions folder when replaced or deleted by Syncthing.": "Файловете биват преместени в .stversions папка, когато са заменен или изтрити от Syncthing.",
    "Files are moved to date stamped versions in a .stversions folder when replaced or deleted by Syncthing.": "Когато syncthing замени или изтрие файл той се премества в  .stversions и преименува с дабавени дата и час.",
    "Files are protected from changes made on other devices, but changes made on this device will be sent to the rest of the cluster.": "Файловете са защитени от промени направени на други устройства, но промени направени на това устройство ще бъдат синхронизирани с другите устройства.",
+    "Folder": "Папка",
    "Folder ID": "Идентификатор на папка",
    "Folder Master": "Главна папка",
    "Folder Path": "Път до папката",
    "Folders": "Папки",
+    "GUI": "Потребителски интефейс",
    "GUI Authentication Password": "Парола за Потребителския Интерфейс",
    "GUI Authentication User": "Потребител за Потребителския Интерфейс",
    "GUI Listen Addresses": "Адрес за Свързване с Потребителския Интерфейс",
@@ -67,10 +74,12 @@
    "Global Discovery Server": "Сървър за Глобално Откриване",
    "Global State": "Глобално състояние",
    "Help": "Помощ",
+    "Home page": "Начална страница",
    "Ignore": "Игнорирай",
    "Ignore Patterns": "Шаблони за Игнориране",
    "Ignore Permissions": "Игнорирай Права за Достъп",
    "Incoming Rate Limit (KiB/s)": "Входящ Лимит на Скоростта (KiB/s)",
+    "Incorrect configuration may damage your folder contents and render Syncthing inoperable.": "Неправилни настройки могат да повредят съдържанието на папката и да попречат на по-нататъшно синхронизиране.",
    "Introducer": "Introducer",
    "Inversion of the given condition (i.e. do not exclude)": "Обратното на даденото условие (пр. не изключвай)",
    "Keep Versions": "Пази Версии",
@@ -80,9 +89,11 @@
    "Later": "По-късно",
    "Local Discovery": "Локално Откриване",
    "Local State": "Локално състояние",
+    "Local State (Total)": "Локално Състояние (Общо)",
    "Major Upgrade": "Основно Обновяване",
    "Maximum Age": "Максимална Възраст",
    "Metadata Only": "Само мета информация",
+    "Minimum Free Disk Space": "Минимално свободно дисково пространство",
    "Move to top of queue": "Премести в началото на опашката",
    "Multi level wildcard (matches multiple directory levels)": "Маска на много нива (покрива папки с много нива)",
    "Never": "Никога",
@@ -95,7 +106,8 @@
    "OK": "ОК",
    "Off": "Изключено",
    "Oldest First": "Най-старите първо",
-    "Out Of Sync": "Не Синхронизиран",
+    "Options": "Настройки",
+    "Out of Sync": "Не синхронизиран",
    "Out of Sync Items": "Несинхронизирани елементи",
    "Outgoing Rate Limit (KiB/s)": "Лимит на Изходящата Скорост (KiB/s)",
    "Override Changes": "Замени Промените",
@@ -108,7 +120,10 @@
    "Quick guide to supported patterns": "Бърз наръчник към поддържаните шаблони",
    "RAM Utilization": "RAM Натоварване",
    "Random": "Произволно",
+    "Relayed via": "Препратено през",
+    "Relays": "Препращачи",
    "Release Notes": "Бележки по обновяването",
+    "Remove": "Премахни",
    "Rescan": "Повторно Сканиране",
    "Rescan All": "Пълно повторно сканиране",
    "Rescan Interval": "Интервал за Повторно Сканиране",
@@ -139,6 +154,7 @@
    "Source Code": "Сорс Код",
    "Staggered File Versioning": "Наслагващи се Файлови Версии",
    "Start Browser": "Стартирай Браузъра",
+    "Statistics": "Статистика",
    "Stopped": "Спряна",
    "Support": "Помощ",
    "Sync Protocol Listen Addresses": "Адрес за слушане на синхронизиращия протокол",
@@ -161,20 +177,25 @@
    "The folder ID must be unique.": "Идентификаторът на папката тряба да бъде уникален.",
    "The folder path cannot be blank.": "Пътят до папката не може да бъде празен.",
    "The following intervals are used: for the first hour a version is kept every 30 seconds, for the first day a version is kept every hour, for the first 30 days a version is kept every day, until the maximum age a version is kept every week.": "Използва се следния интервал: за първия час се пази версия всеки 30 секунди, за първия ден се пази версия всеки час, за първите 30 дена се пази версия всеки ден, до максимума се пази една версия всяка седмица.",
+    "The following items could not be synchronized.": "Следните не могат да бъдат синхронизирани.",
    "The maximum age must be a number and cannot be blank.": "Максималната възраст трябва да е число и не може д ае празна.",
    "The maximum time to keep a version (in days, set to 0 to keep versions forever).": "Максималното време да се пазят весрсии (в дни, сложи 0, за да пазиш версии завинаги).",
-    "The number of days must be a number and cannot be blank.": "The number of days must be a number and cannot be blank.",
-    "The number of days to keep files in the trash can. Zero means forever.": "The number of days to keep files in the trash can. Zero means forever.",
+    "The minimum free disk space percentage must be a non-negative number between 0 and 100 (inclusive).": "Минималното свободно дисково пространство в проценти трябва да е между 0 и 100 (включително).",
+    "The number of days must be a number and cannot be blank.": "Броят дни трябва да бъде число и неможе да бъде празно.",
+    "The number of days to keep files in the trash can. Zero means forever.": "Броят дни за запазване на файловете в кошчето. Нула значи завинаги.",
    "The number of old versions to keep, per file.": "Броят стари версии, които да бъдат пазени за всеки файл.",
    "The number of versions must be a number and cannot be blank.": "Броят версии трябва да бъде число и не може да бъде празно.",
    "The path cannot be blank.": "Пътят неможе да бъде празен.",
+    "The rate limit must be a non-negative number (0: no limit)": "Ограничението на скорста трябва да бъде положително число (0: неограничено)",
    "The rescan interval must be a non-negative number of seconds.": "Интервала на сканиране трябва да бъде не отрицателно число в секунди.",
+    "They are retried automatically and will be synced when the error is resolved.": "Ще бъдат спрени и автоматично синхронизирани, когато грешката бъде оправена.",
    "This is a major version upgrade.": "Това е нова основна версия.",
-    "Trash Can File Versioning": "Trash Can File Versioning",
+    "Trash Can File Versioning": "Версии на файлове в кошчето",
    "Unknown": "Неясен",
    "Unshared": "Споделянето прекратено",
    "Unused": "Неизползван",
    "Up to Date": "Актуален",
+    "Updated": "Обновено",
    "Upgrade": "Обнови",
    "Upgrade To {%version%}": "Обновен До {{version}}",
    "Upgrading": "Обновяване",
--- a/Show More
+++ b/Show More