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-rw-r--r--zlib/uncompr.c100
1 files changed, 66 insertions, 34 deletions
diff --git a/zlib/uncompr.c b/zlib/uncompr.c
index b59e3d0defb..f03a1a865e3 100644
--- a/zlib/uncompr.c
+++ b/zlib/uncompr.c
@@ -1,5 +1,5 @@
/* uncompr.c -- decompress a memory buffer
- * Copyright (C) 1995-2003 Jean-loup Gailly.
+ * Copyright (C) 1995-2003, 2010, 2014, 2016 Jean-loup Gailly, Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@@ -9,53 +9,85 @@
#include "zlib.h"
/* ===========================================================================
- Decompresses the source buffer into the destination buffer. sourceLen is
- the byte length of the source buffer. Upon entry, destLen is the total
- size of the destination buffer, which must be large enough to hold the
- entire uncompressed data. (The size of the uncompressed data must have
- been saved previously by the compressor and transmitted to the decompressor
- by some mechanism outside the scope of this compression library.)
- Upon exit, destLen is the actual size of the compressed buffer.
- This function can be used to decompress a whole file at once if the
- input file is mmap'ed.
-
- uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
- enough memory, Z_BUF_ERROR if there was not enough room in the output
- buffer, or Z_DATA_ERROR if the input data was corrupted.
+ Decompresses the source buffer into the destination buffer. *sourceLen is
+ the byte length of the source buffer. Upon entry, *destLen is the total size
+ of the destination buffer, which must be large enough to hold the entire
+ uncompressed data. (The size of the uncompressed data must have been saved
+ previously by the compressor and transmitted to the decompressor by some
+ mechanism outside the scope of this compression library.) Upon exit,
+ *destLen is the size of the decompressed data and *sourceLen is the number
+ of source bytes consumed. Upon return, source + *sourceLen points to the
+ first unused input byte.
+
+ uncompress returns Z_OK if success, Z_MEM_ERROR if there was not enough
+ memory, Z_BUF_ERROR if there was not enough room in the output buffer, or
+ Z_DATA_ERROR if the input data was corrupted, including if the input data is
+ an incomplete zlib stream.
*/
-int ZEXPORT uncompress (dest, destLen, source, sourceLen)
+int ZEXPORT uncompress2 (dest, destLen, source, sourceLen)
Bytef *dest;
uLongf *destLen;
const Bytef *source;
- uLong sourceLen;
+ uLong *sourceLen;
{
z_stream stream;
int err;
+ const uInt max = (uInt)-1;
+ uLong len, left;
+ Byte buf[1]; /* for detection of incomplete stream when *destLen == 0 */
- stream.next_in = (Bytef*)source;
- stream.avail_in = (uInt)sourceLen;
- /* Check for source > 64K on 16-bit machine: */
- if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
-
- stream.next_out = dest;
- stream.avail_out = (uInt)*destLen;
- if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR;
+ len = *sourceLen;
+ if (*destLen) {
+ left = *destLen;
+ *destLen = 0;
+ }
+ else {
+ left = 1;
+ dest = buf;
+ }
+ stream.next_in = (z_const Bytef *)source;
+ stream.avail_in = 0;
stream.zalloc = (alloc_func)0;
stream.zfree = (free_func)0;
+ stream.opaque = (voidpf)0;
err = inflateInit(&stream);
if (err != Z_OK) return err;
- err = inflate(&stream, Z_FINISH);
- if (err != Z_STREAM_END) {
- inflateEnd(&stream);
- if (err == Z_NEED_DICT || (err == Z_BUF_ERROR && stream.avail_in == 0))
- return Z_DATA_ERROR;
- return err;
- }
- *destLen = stream.total_out;
+ stream.next_out = dest;
+ stream.avail_out = 0;
+
+ do {
+ if (stream.avail_out == 0) {
+ stream.avail_out = left > (uLong)max ? max : (uInt)left;
+ left -= stream.avail_out;
+ }
+ if (stream.avail_in == 0) {
+ stream.avail_in = len > (uLong)max ? max : (uInt)len;
+ len -= stream.avail_in;
+ }
+ err = inflate(&stream, Z_NO_FLUSH);
+ } while (err == Z_OK);
- err = inflateEnd(&stream);
- return err;
+ *sourceLen -= len + stream.avail_in;
+ if (dest != buf)
+ *destLen = stream.total_out;
+ else if (stream.total_out && err == Z_BUF_ERROR)
+ left = 1;
+
+ inflateEnd(&stream);
+ return err == Z_STREAM_END ? Z_OK :
+ err == Z_NEED_DICT ? Z_DATA_ERROR :
+ err == Z_BUF_ERROR && left + stream.avail_out ? Z_DATA_ERROR :
+ err;
+}
+
+int ZEXPORT uncompress (dest, destLen, source, sourceLen)
+ Bytef *dest;
+ uLongf *destLen;
+ const Bytef *source;
+ uLong sourceLen;
+{
+ return uncompress2(dest, destLen, source, &sourceLen);
}