return ret;
}
-static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
- const uint8_t *buf, int buf_size)
+/*
+ * qcow2_decompress()
+ *
+ * Decompress some data (not more than @src_size bytes) to produce exactly
+ * @dest_size bytes.
+ *
+ * @dest - destination buffer, @dest_size bytes
+ * @src - source buffer, @src_size bytes
+ *
+ * Returns: 0 on success
+ * -1 on fail
+ */
+static ssize_t qcow2_decompress(void *dest, size_t dest_size,
+ const void *src, size_t src_size)
{
- z_stream strm1, *strm = &strm1;
- int ret, out_len;
-
- memset(strm, 0, sizeof(*strm));
+ int ret = 0;
+ z_stream strm;
- strm->next_in = (uint8_t *)buf;
- strm->avail_in = buf_size;
- strm->next_out = out_buf;
- strm->avail_out = out_buf_size;
+ memset(&strm, 0, sizeof(strm));
+ strm.avail_in = src_size;
+ strm.next_in = (void *) src;
+ strm.avail_out = dest_size;
+ strm.next_out = dest;
- ret = inflateInit2(strm, -12);
+ ret = inflateInit2(&strm, -12);
if (ret != Z_OK) {
return -1;
}
- ret = inflate(strm, Z_FINISH);
- out_len = strm->next_out - out_buf;
- if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) ||
- out_len != out_buf_size) {
- inflateEnd(strm);
- return -1;
+
+ ret = inflate(&strm, Z_FINISH);
+ 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;
}
- inflateEnd(strm);
- return 0;
+
+ inflateEnd(&strm);
+
+ return ret;
}
#define MAX_COMPRESS_THREADS 4
if (ret < 0) {
return ret;
}
- if (decompress_buffer(s->cluster_cache, s->cluster_size,
- s->cluster_data + sector_offset, csize) < 0) {
+ if (qcow2_decompress(s->cluster_cache, s->cluster_size,
+ s->cluster_data + sector_offset, csize) < 0) {
return -EIO;
}
s->cluster_cache_offset = coffset;