X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=compress.c;h=e2db404abf888bd2c85844985b5ae9784b955c63;hb=2d80d3f6b52f9fa454c26c89d2d6a1790e1cecb0;hp=b77674af9f5e27006d3ebdbcbd939312b1a83e53;hpb=6759211ad8a5006689216a86c3267bb503bfccc1;p=zlib.git

diff --git a/compress.c b/compress.c
index b77674a..e2db404 100644
--- a/compress.c
+++ b/compress.c
@@ -1,10 +1,11 @@
 /* compress.c -- compress a memory buffer
- * Copyright (C) 1995-1998 Jean-loup Gailly.
- * For conditions of distribution and use, see copyright notice in zlib.h 
+ * Copyright (C) 1995-2005, 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"
 
 /* ===========================================================================
@@ -18,7 +19,7 @@
    memory, Z_BUF_ERROR if there was not enough room in the output buffer,
    Z_STREAM_ERROR if the level parameter is invalid.
 */
-int EXPORT compress2 (dest, destLen, source, sourceLen, level)
+int ZEXPORT compress2 (dest, destLen, source, sourceLen, level)
     Bytef *dest;
     uLongf *destLen;
     const Bytef *source;
@@ -27,16 +28,11 @@ int EXPORT compress2 (dest, destLen, source, sourceLen, level)
 {
     z_stream stream;
     int err;
+    const uInt max = (uInt)-1;
+    uLong left;
 
-    stream.next_in = (Bytef*)source;
-    stream.avail_in = (uInt)sourceLen;
-#ifdef MAXSEG_64K
-    /* Check for source > 64K on 16-bit machine: */
-    if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR;
-#endif
-    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;
@@ -45,20 +41,31 @@ int EXPORT compress2 (dest, destLen, source, sourceLen, level)
     err = deflateInit(&stream, level);
     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;
 }
 
 /* ===========================================================================
  */
-int EXPORT compress (dest, destLen, source, sourceLen)
+int ZEXPORT compress (dest, destLen, source, sourceLen)
     Bytef *dest;
     uLongf *destLen;
     const Bytef *source;
@@ -66,3 +73,14 @@ int EXPORT compress (dest, destLen, source, sourceLen)
 {
     return compress2(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION);
 }
+
+/* ===========================================================================
+     If the default memLevel or windowBits for deflateInit() is changed, then
+   this function needs to be updated.
+ */
+uLong ZEXPORT compressBound (sourceLen)
+    uLong sourceLen;
+{
+    return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) +
+           (sourceLen >> 25) + 13;
+}