include/u-boot, lib/zlib: add sources for zlib decompression
Add zlib (v1.2.11) uncompr() function to U-Boot. SquashFS depends on
this function to decompress data from a raw disk image. The actual
support for zlib into SquashFS sources will be added in a follow-up
commit.
Signed-off-by: Joao Marcos Costa <joaomarcos.costa@bootlin.com>
diff --git a/lib/zlib/uncompr.c b/lib/zlib/uncompr.c
new file mode 100644
index 0000000..21e9393
--- /dev/null
+++ b/lib/zlib/uncompr.c
@@ -0,0 +1,97 @@
+/* uncompr.c -- decompress a memory buffer
+ * Copyright (C) 1995-2003, 2010, 2014, 2016 Jean-loup Gailly, Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* @(#) $Id$ */
+
+#define ZLIB_INTERNAL
+#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 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 uncompress2(dest, destLen, source, sourceLen)
+ Bytef *dest;
+ uLongf *destLen;
+ const Bytef *source;
+ uLong *sourceLen;
+
+{
+ z_stream stream;
+ int err;
+ const uInt max = (uInt)-1;
+ uLong len, left;
+ /* for detection of incomplete stream when *destLen == 0 */
+ Byte buf[1];
+
+ 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;
+
+ 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);
+
+ *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);
+}