From: glennrp <glennrp@git.imagemagick.org>
Date: Fri, 1 Jul 2011 02:52:59 +0000 (+0000)
Subject: Avoid using Z_RLE and Z_FIXED with old zlib versions that don't support them.
X-Git-Tag: 7.0.1-0~7393
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=98c07ad97d2b2c4571ec3b58241df30d43ba51d0;p=imagemagick

Avoid using Z_RLE and Z_FIXED with old zlib versions that don't support them.
---

diff --git a/coders/png.c b/coders/png.c
index d53265b51..1abebc378 100644
--- a/coders/png.c
+++ b/coders/png.c
@@ -11053,10 +11053,18 @@ static MagickBooleanType WritePNGImage(const ImageInfo *image_info,
         mng_info->write_png_compression_strategy = Z_HUFFMAN_ONLY+1;
 
       else if (LocaleCompare(value,"3") == 0)
+#ifdef Z_RLE  /* Z_RLE was added to zlib-1.2.0 */
         mng_info->write_png_compression_strategy = Z_RLE+1;
+#else
+        mng_info->write_png_compression_strategy = Z_DEFAULT_STRATEGY+1;
+#endif
 
       else if (LocaleCompare(value,"4") == 0)
+#ifdef Z_FIXED  /* Z_FIXED was added to zlib-1.2.2.2 */
         mng_info->write_png_compression_strategy = Z_FIXED+1;
+#else
+        mng_info->write_png_compression_strategy = Z_DEFAULT_STRATEGY+1;
+#endif
 
       else
         (void) ThrowMagickException(&image->exception,