From: Mark Adler <madler@alumni.caltech.edu>
Date: Sat, 26 Apr 2014 04:52:19 +0000 (-0700)
Subject: Fix compress() to work on lengths more than a maximum unsigned.
X-Git-Tag: 1.9.9-b1~793^2~16
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6aa9399790e266d431e658d06509e781b5cc83d1;p=thirdparty%2Fzlib-ng.git

Fix compress() to work on lengths more than a maximum unsigned.

 Conflicts:
	compress.c
---

diff --git a/compress.c b/compress.c
index 0bf1b0fc2..abae9b3ae 100644
--- a/compress.c
+++ b/compress.c
@@ -1,5 +1,5 @@
 /* compress.c -- compress a memory buffer
- * Copyright (C) 1995-2005 Jean-loup Gailly.
+ * Copyright (C) 1995-2005, 2014 Jean-loup Gailly, Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
@@ -23,13 +23,11 @@ int ZEXPORT compress2(unsigned char *dest, uLong *destLen, const unsigned char *
                         uLong sourceLen, int level) {
     z_stream stream;
     int err;
+    const uInt max = -1;
+    uLong left;
 
-    stream.next_in = (const unsigned char *)source;
-    stream.avail_in = (uInt)sourceLen;
-    stream.next_out = dest;
-    stream.avail_out = (uInt)*destLen;
-    if ((uLong)stream.avail_out != *destLen)
-        return Z_BUF_ERROR;
+    left = *destLen;
+    *destLen = 0;
 
     stream.zalloc = (alloc_func)0;
     stream.zfree = (free_func)0;
@@ -39,15 +37,26 @@ int ZEXPORT compress2(unsigned char *dest, uLong *destLen, const unsigned char *
     if (err != Z_OK)
         return err;
 
-    err = deflate(&stream, Z_FINISH);
-    if (err != Z_STREAM_END) {
-        deflateEnd(&stream);
-        return err == Z_OK ? Z_BUF_ERROR : err;
-    }
-    *destLen = stream.total_out;
+    stream.next_out = dest;
+    stream.avail_out = 0;
+    stream.next_in = (z_const Bytef *)source;
+    stream.avail_in = 0;
 
-    err = deflateEnd(&stream);
-    return err;
+    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 = sourceLen > (uLong)max ? max : (uInt)sourceLen;
+            sourceLen -= stream.avail_in;
+        }
+        err = deflate(&stream, sourceLen ? Z_NO_FLUSH : Z_FINISH);
+    } while (err == Z_OK);
+
+    *destLen = stream.total_out;
+    deflateEnd(&stream);
+    return err == Z_STREAM_END ? Z_OK : err;
 }
 
 /* ===========================================================================