Use size_t rather than int to track dynamic buffer size.

This lets use create dynamic buffers larger than 2GB.

src/calendar.c

@@ -1336,7 +1336,7 @@ static void WriteCalTrailer(void)
 /***************************************************************/
 static int DoCalRem(ParsePtr p, int col)
 {
-    int oldLen;
+    size_t oldLen;
     Trigger trig;
     TimeTrig tim;
     Value v;

src/dynbuf.c

@@ -27,11 +27,11 @@
  Doubles the size of dynamic buffer until it has room for at least
  'n' characters, not including trailing '\0'
 **********************************************************************/
-static int DBufMakeRoom(DynamicBuffer *dbuf, int n)
+static int DBufMakeRoom(DynamicBuffer *dbuf, size_t n)
 {
     /* Double size until it's greater than n (strictly > to leave room
        for trailing '\0' */
-    int size = dbuf->allocatedLen;
+    size_t size = dbuf->allocatedLen;
     char *buf;
 
     if (size > n) return OK;

src/dynbuf.h

@@ -17,8 +17,8 @@
 #define DBUF_STATIC_SIZE 128
 typedef struct {
     char *buffer;
-    int len;
-    int allocatedLen;
+    size_t len;
+    size_t allocatedLen;
     char staticBuf[DBUF_STATIC_SIZE];
 } DynamicBuffer;
 

src/funcs.c

@@ -433,7 +433,9 @@ static int FStrlen(func_info *info)
     Value *v = &ARG(0);
     if (v->type != STR_TYPE) return E_BAD_TYPE;
     RetVal.type = INT_TYPE;
-    RETVAL = strlen(v->v.str);
+    size_t l = strlen(v->v.str);
+    if (l > INT_MAX) return E_2HIGH;
+    RETVAL = (int) l;
     return OK;
 }
 
@@ -1594,7 +1596,7 @@ static int FShell(func_info *info)
 	    DBufFree(&buf);
 	    return E_NO_MEM;
 	}
-	if (maxlen > 0 && DBufLen(&buf) >= maxlen) {
+	if (maxlen > 0 && DBufLen(&buf) >= (size_t) maxlen) {
 	    break;
 	}
     }