From: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
On success path we return what inflate() returns instead of 0. And it
most probably works for Z_STREAM_END as it is positive, but is
definitely broken for Z_BUF_ERROR.
While being here, switch to errno return code, to be closer to
qcow2_compress API (and usual expectations).
Revert condition in if to be more positive. Drop dead initialization of
ret.
Cc: qemu-sta...@nongnu.org # v4.0
Fixes: 341926ab83e2b
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Reviewed-by: Alberto Garcia <be...@igalia.com>
---
block/qcow2-threads.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/block/qcow2-threads.c b/block/qcow2-threads.c
index 77bb578cdf..a68126f291 100644
--- a/block/qcow2-threads.c
+++ b/block/qcow2-threads.c
@@ -128,12 +128,12 @@ static ssize_t qcow2_compress(void *dest, size_t
dest_size,
* @src - source buffer, @src_size bytes
*
* Returns: 0 on success
- * -1 on fail
+ * -EIO on fail
*/
static ssize_t qcow2_decompress(void *dest, size_t dest_size,
const void *src, size_t src_size)
{
- int ret = 0;
+ int ret;
z_stream strm;
memset(&strm, 0, sizeof(strm));
@@ -144,17 +144,19 @@ static ssize_t qcow2_decompress(void *dest, size_t
dest_size,
ret = inflateInit2(&strm, -12);
if (ret != Z_OK) {
- return -1;
+ return -EIO;
}
ret = inflate(&strm, Z_FINISH);
- if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) || strm.avail_out != 0) {
+ if ((ret == Z_STREAM_END || ret == Z_BUF_ERROR) && strm.avail_out == 0) {
/*
* We approve Z_BUF_ERROR because we need @dest buffer to be filled,
but
* @src buffer may be processed partly (because in qcow2 we know size
of
* compressed data with precision of one sector)
*/
- ret = -1;
+ ret = 0;
+ } else {
+ ret = -EIO;
}
inflateEnd(&strm);
--
2.17.0
