use scope guard in the gif encoder

LearnBoost · Aug 13, 2010 · 42cb392 · 42cb392
1 parent 7be01eb
commit 42cb392
Showing 1 changed file with 9 additions and 34 deletions.
diff --git a/src/gif_encoder.cpp b/src/gif_encoder.cpp
@@ -3,6 +3,8 @@
 #include <cstdlib>
 #include <cstring>
 
+#include "loki/ScopeGuard.h"
+
 #include "gif_encoder.h"
 #include "palette.h"
 #include "quantize.h"
@@ -148,48 +150,36 @@ GifEncoder::encode()
 
     int color_map_size = 256;
     ColorMapObject *output_color_map = MakeMapObject(256, ext_web_safe_palette);
-    if (!output_color_map) {
+    LOKI_ON_BLOCK_EXIT(FreeMapObject, output_color_map);
+    if (!output_color_map)
         throw "MakeMapObject in GifEncoder::encode failed";
-    }
 
     GifByteType *gif_buf = (GifByteType *)malloc(sizeof(GifByteType)*width*height);
-    if (!gif_buf) {
-        FreeMapObject(output_color_map);
+    LOKI_ON_BLOCK_EXIT(free, gif_buf);
+    if (!gif_buf)
         throw "malloc in GifEncoder::encode failed";
-    }
 
     if (web_safe_quantize(width, height, rgb.red, rgb.green, rgb.blue, gif_buf) == GIF_ERROR)
-    {
-        FreeMapObject(output_color_map);
-        free(gif_buf);
         throw "web_safe_quantize in GifEncoder::encode failed";
-    }
 
     /*
     if (QuantizeBuffer(width, height, &color_map_size,
         rgb.red, rgb.green, rgb.blue,
         gif_buf, output_color_map->Colors) == GIF_ERROR)
     {
-        FreeMapObject(output_color_map);
-        free(gif_buf);
         throw "QuantizeBuffer in GifEncoder::encode failed";
     }
     */
 
     GifFileType *gif_file = EGifOpen(&gif, gif_writer);
-    if (!gif_file) {
-        FreeMapObject(output_color_map);
-        free(gif_buf);
+    LOKI_ON_BLOCK_EXIT(EGifCloseFile, gif_file);
+    if (!gif_file)
         throw "EGifOpen in GifEncoder::encode failed";
-    }
 
     EGifSetGifVersion("89a");
     if (EGifPutScreenDesc(gif_file, width, height,
         color_map_size, 0, output_color_map) == GIF_ERROR)
     {
-        FreeMapObject(output_color_map);
-        free(gif_buf);
-        EGifCloseFile(gif_file);
         throw "EGifPutScreenDesc in GifEncoder::encode failed";
     }
 
@@ -206,26 +196,15 @@ GifEncoder::encode()
     }
 
     if (EGifPutImageDesc(gif_file, 0, 0, width, height, FALSE, NULL) == GIF_ERROR) {
-        FreeMapObject(output_color_map);
-        free(gif_buf);
-        EGifCloseFile(gif_file);
         throw "EGifPutImageDesc in GifEncoder::encode failed";
     }
 
     GifByteType *gif_bufp = gif_buf;
     for (int i = 0; i < height; i++) {
-        if (EGifPutLine(gif_file, gif_bufp, width) == GIF_ERROR) {
-            FreeMapObject(output_color_map);
-            free(gif_buf);
-            EGifCloseFile(gif_file);
+        if (EGifPutLine(gif_file, gif_bufp, width) == GIF_ERROR)
             throw "EGifPutLine in GifEncoder::encode failed";
-        }
         gif_bufp += width;
     }
-
-    FreeMapObject(output_color_map);
-    free(gif_buf);
-    EGifCloseFile(gif_file);
 }
 
 void
@@ -300,11 +279,7 @@ AnimatedGifEncoder::new_frame(unsigned char *data, int delay)
     RGBator rgb(data, width, height, buf_type);
 
     if (web_safe_quantize(width, height, rgb.red, rgb.green, rgb.blue, gif_buf) == GIF_ERROR)
-    {
-        FreeMapObject(output_color_map);
-        free(gif_buf);
         throw "web_safe_quantize in AnimatedGifEncoder::new_frame failed";
-    }
 
     /*
     if (QuantizeBuffer(width, height, &color_map_size,