@matheusbsbs / matheus-bagliano / commits / f8b090386b

index-pack: loop while inflating objects in unpack_data

When the unpack_data function is given a consume() callback, it unpacks only 64K of the input at a time, feeding it to git_inflate along with a 64K output buffer. However, because we are inflating, there is a good chance that the output buffer will fill before consuming all of the input. In this case, we need to loop on git_inflate until we have fed the whole input buffer, feeding each chunk of output to the consume buffer. The current code does not do this, and as a result, will fail the loop condition and trigger a fatal "serious inflate inconsistency" error in this case. While we're rearranging the loop, let's get rid of the extra last_out pointer. It is meant to point to the beginning of the buffer that we feed to git_inflate, but in practice this is always the beginning of our same 64K buffer, because: 1. At the beginning of the loop, we are feeding the buffer. 2. At the end of the loop, if we are using a consume() function, we reset git_inflate's pointer to the beginning of the buffer. If we are not using a consume() function, then we do not care about the value of last_out at all. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jeff King committed Jul 4, 2012 at 03:12 UTC f8b090386bb5af172ea95f16ad6274e02222d2c1

1 file changed +13 -10

builtin/index-pack.c

+13 -10

@@ -524,7 +524,6 @@ static void *unpack_data(struct object_entry *obj,

524 stream.avail_out = consume ? 64*1024 : obj->size;

525

526 do {

527 - unsigned char *last_out = stream.next_out;

527 ssize_t n = (len < 64*1024) ? len : 64*1024;

528 n = pread(pack_fd, inbuf, n, from);

529 if (n < 0)

@@ -538,15 +537,19 @@ static void *unpack_data(struct object_entry *obj,

537 len -= n;

538 stream.next_in = inbuf;

539 stream.avail_in = n;

541 - status = git_inflate(&stream, 0);

542 - if (consume) {

543 - if (consume(last_out, stream.next_out - last_out, cb_data)) {

544 - free(inbuf);

545 - free(data);

546 - return NULL;

547 - }

548 - stream.next_out = data;

549 - stream.avail_out = 64*1024;

540 + if (!consume)

541 + status = git_inflate(&stream, 0);

542 + else {

543 + do {

544 + status = git_inflate(&stream, 0);

545 + if (consume(data, stream.next_out - data, cb_data)) {

546 + free(inbuf);

547 + free(data);

548 + return NULL;

549 + }

550 + stream.next_out = data;

551 + stream.avail_out = 64*1024;

552 + } while (status == Z_OK && stream.avail_in);

553 }

554 } while (len && status == Z_OK && !stream.avail_in);

555