Merge pull request #54 from SDWebImage/bugfix_encoding_leak

Fix the encoding leak when input CGImage is not RGBA8888 or RGB888

Author: dreampiggy

SDWebImageWebPCoder/Classes/SDImageWebPCoder.m

@@ -762,20 +762,21 @@ - (nullable NSData *)sd_encodedWebpDataWithImage:(nullable CGImageRef)imageRef
     if (!dataProvider) {
         return nil;
     }
-    CFDataRef dataRef = CGDataProviderCopyData(dataProvider);
-    if (!dataRef) {
-        return nil;
-    }
     // Check colorSpace is RGB/RGBA
     CGColorSpaceRef colorSpace = CGImageGetColorSpace(imageRef);
     BOOL isRGB = CGColorSpaceGetModel(colorSpace) == kCGColorSpaceModelRGB;
 
+    CFDataRef dataRef;
     uint8_t *rgba = NULL; // RGBA Buffer managed by CFData, don't call `free` on it, instead call `CFRelease` on `dataRef`
     // We could not assume that input CGImage's color mode is always RGB888/RGBA8888. Convert all other cases to target color mode using vImage
     BOOL isRGB888 = isRGB && byteOrderNormal && alphaInfo == kCGImageAlphaNone && components == 3;
     BOOL isRGBA8888 = isRGB && byteOrderNormal && alphaInfo == kCGImageAlphaLast && components == 4;
     if (isRGB888 || isRGBA8888) {
         // If the input CGImage is already RGB888/RGBA8888
+        dataRef = CGDataProviderCopyData(dataProvider);
+        if (!dataRef) {
+            return nil;
+        }
         rgba = (uint8_t *)CFDataGetBytePtr(dataRef);
     } else {
         // Convert all other cases to target color mode using vImage
@@ -798,37 +799,37 @@ - (nullable NSData *)sd_encodedWebpDataWithImage:(nullable CGImageRef)imageRef
 
         convertor = vImageConverter_CreateWithCGImageFormat(&srcFormat, &destFormat, NULL, kvImageNoFlags, &error);
         if (error != kvImageNoError) {
-            CFRelease(dataRef);
             return nil;
         }
 
         vImage_Buffer src;
         error = vImageBuffer_InitWithCGImage(&src, &srcFormat, nil, imageRef, kvImageNoFlags);
         if (error != kvImageNoError) {
             vImageConverter_Release(convertor);
-            CFRelease(dataRef);
             return nil;
         }
 
         vImage_Buffer dest;
         error = vImageBuffer_Init(&dest, height, width, destFormat.bitsPerPixel, kvImageNoFlags);
         if (error != kvImageNoError) {
             vImageConverter_Release(convertor);
-            CFRelease(dataRef);
+            free(src.data);
             return nil;
         }
 
         // Convert input color mode to RGB888/RGBA8888
         error = vImageConvert_AnyToAny(convertor, &src, &dest, NULL, kvImageNoFlags);
+        
+        // Free the buffer
+        free(src.data);
         vImageConverter_Release(convertor);
         if (error != kvImageNoError) {
-            CFRelease(dataRef);
+            free(dest.data);
             return nil;
         }
 
         rgba = dest.data; // Converted buffer
         bytesPerRow = dest.rowBytes; // Converted bytePerRow
-        CFRelease(dataRef); // Use CFData to manage bytes for free, the same code path for error handling
         dataRef = CFDataCreateWithBytesNoCopy(kCFAllocatorDefault, rgba, bytesPerRow * height, kCFAllocatorDefault);
     }