Support pdf files larger than 2Gig.

If FZ_LARGEFILE is defined when building, MuPDF uses 64bit offsets
for files; this allows us to open streams larger than 2Gig.

The downsides to this are that:

 * The xref entries are larger.

 * All PDF ints are held as 64bit things rather than 32bit things
   (to cope with /Prev entries, hint stream offsets etc).

 * All file positions are stored as 64bits rather than 32.

The implementation works by detecting FZ_LARGEFILE. Some #ifdeffery
in fitz/system.h sets fz_off_t to either int or int64_t as appropriate,
and sets defines for fz_fopen, fz_fseek, fz_ftell etc as required.

These call the fseeko64 etc functions on linux (and so define
_LARGEFILE64_SOURCE) and the explicit 64bit functions on windows.

1 files changed, 3 insertions, 3 deletions

diff --git a/source/fitz/stream-read.c b/source/fitz/stream-read.c
index 75261ea5..e555314d 100644
--- a/source/fitz/stream-read.c
+++ b/source/fitz/stream-read.c
@@ -114,21 +114,21 @@ fz_read_line(fz_context *ctx, fz_stream *stm, char *mem, int n)
 		*s = '\0';
 }
 
-int
+fz_off_t
 fz_tell(fz_context *ctx, fz_stream *stm)
 {
 	return stm->pos - (stm->wp - stm->rp);
 }
 
 void
-fz_seek(fz_context *ctx, fz_stream *stm, int offset, int whence)
+fz_seek(fz_context *ctx, fz_stream *stm, fz_off_t offset, int whence)
 {
 	stm->avail = 0; /* Reset bit reading */
 	if (stm->seek)
 	{
 		if (whence == 1)
 		{
-			offset = fz_tell(ctx, stm) + offset;
+			offset += fz_tell(ctx, stm);
 			whence = 0;
 		}
 		stm->seek(ctx, stm, offset, whence);