Using try-catch for CoreSVG vector image before rendering on screen, protect some crash for user

However, this can only solve some of crashes, some of crashes like Danger Pointer are un-catchable

Author: dreampiggy

Example/SDWebImageSVGCoder/SDViewController.m

@@ -25,6 +25,11 @@ - (void)viewDidLoad
     NSURL *svgURL = [NSURL URLWithString:@"https://dev.w3.org/SVG/tools/svgweb/samples/svg-files/w3c.svg"];
     NSURL *svgURL2 = [NSURL URLWithString:@"https://dev.w3.org/SVG/tools/svgweb/samples/svg-files/wikimedia.svg"];
     NSURL *svgURL3 = [NSURL URLWithString:@"https://simpleicons.org/icons/github.svg"];
+    // Some SVG will fail, this demo check them and the C++/Objc exception should be catched by SDK
+    NSURL *badSVGURL = [NSURL URLWithString:@"https://openseauserdata.com/files/b809fe0925eb3629bb1d3edb1fafcc88.svg"];
+    [SDWebImageManager.sharedManager loadImageWithURL:badSVGURL options:0 progress:nil completed:^(UIImage * _Nullable image, NSData * _Nullable data, NSError * _Nullable error, SDImageCacheType cacheType, BOOL finished, NSURL * _Nullable imageURL) {
+        
+    }];
 
     CGSize screenSize = self.view.bounds.size;
 

SDWebImageSVGCoder/Classes/SDImageSVGCoder.m

@@ -49,12 +49,12 @@ + (SDImageSVGCoder *)sharedCoder {
 }
 
 + (void)initialize {
-    SDCGSVGDocumentRetain = dlsym(RTLD_DEFAULT, SDBase64DecodedString(@"Q0dTVkdEb2N1bWVudFJldGFpbg==").UTF8String);
-    SDCGSVGDocumentRelease = dlsym(RTLD_DEFAULT, SDBase64DecodedString(@"Q0dTVkdEb2N1bWVudFJlbGVhc2U=").UTF8String);
-    SDCGSVGDocumentCreateFromData = dlsym(RTLD_DEFAULT, SDBase64DecodedString(@"Q0dTVkdEb2N1bWVudENyZWF0ZUZyb21EYXRh").UTF8String);
-    SDCGSVGDocumentWriteToData = dlsym(RTLD_DEFAULT, SDBase64DecodedString(@"Q0dTVkdEb2N1bWVudFdyaXRlVG9EYXRh").UTF8String);
-    SDCGContextDrawSVGDocument = dlsym(RTLD_DEFAULT, SDBase64DecodedString(@"Q0dDb250ZXh0RHJhd1NWR0RvY3VtZW50").UTF8String);
-    SDCGSVGDocumentGetCanvasSize = dlsym(RTLD_DEFAULT, SDBase64DecodedString(@"Q0dTVkdEb2N1bWVudEdldENhbnZhc1NpemU=").UTF8String);
+    SDCGSVGDocumentRetain = (CGSVGDocumentRef (*)(CGSVGDocumentRef))dlsym(RTLD_DEFAULT, SDBase64DecodedString(@"Q0dTVkdEb2N1bWVudFJldGFpbg==").UTF8String);
+    SDCGSVGDocumentRelease = (void (*)(CGSVGDocumentRef))dlsym(RTLD_DEFAULT, SDBase64DecodedString(@"Q0dTVkdEb2N1bWVudFJlbGVhc2U=").UTF8String);
+    SDCGSVGDocumentCreateFromData = (CGSVGDocumentRef (*)(CFDataRef data, CFDictionaryRef options))dlsym(RTLD_DEFAULT, SDBase64DecodedString(@"Q0dTVkdEb2N1bWVudENyZWF0ZUZyb21EYXRh").UTF8String);
+    SDCGSVGDocumentWriteToData = (void (*)(CGSVGDocumentRef document, CFDataRef data, CFDictionaryRef options))dlsym(RTLD_DEFAULT, SDBase64DecodedString(@"Q0dTVkdEb2N1bWVudFdyaXRlVG9EYXRh").UTF8String);
+    SDCGContextDrawSVGDocument = (void (*)(CGContextRef context, CGSVGDocumentRef document))dlsym(RTLD_DEFAULT, SDBase64DecodedString(@"Q0dDb250ZXh0RHJhd1NWR0RvY3VtZW50").UTF8String);
+    SDCGSVGDocumentGetCanvasSize = (CGSize (*)(CGSVGDocumentRef document))dlsym(RTLD_DEFAULT, SDBase64DecodedString(@"Q0dTVkdEb2N1bWVudEdldENhbnZhc1NpemU=").UTF8String);
 #if SD_UIKIT || SD_WATCH
     SDImageWithCGSVGDocumentSEL = NSSelectorFromString(SDBase64DecodedString(@"X2ltYWdlV2l0aENHU1ZHRG9jdW1lbnQ6"));
     SDCGSVGDocumentSEL = NSSelectorFromString(SDBase64DecodedString(@"X0NHU1ZHRG9jdW1lbnQ="));
@@ -152,7 +152,12 @@ - (NSData *)encodedDataWithImage:(UIImage *)image format:(SDImageFormat)format o
         return nil;
     }
 
-    SDCGSVGDocumentWriteToData(document, (__bridge CFDataRef)data, NULL);
+    @try {
+        SDCGSVGDocumentWriteToData(document, (__bridge CFMutableDataRef)data, NULL);
+    } @catch (...) {
+        // CoreSVG export failed
+        return nil;
+    }
 
     return [data copy];
 }
@@ -178,6 +183,23 @@ - (UIImage *)createVectorSVGWithData:(nonnull NSData *)data {
     image = ((UIImage *(*)(id,SEL,CGSVGDocumentRef))[UIImage.class methodForSelector:SDImageWithCGSVGDocumentSEL])(UIImage.class, SDImageWithCGSVGDocumentSEL, document);
     SDCGSVGDocumentRelease(document);
 #endif
+    
+    // CoreSVG has compatible for some SVG/1.1 format (like Font issue) and may crash when rendering on screen (not here, Core Animation commit time)
+    // So, we snapshot a 1x1 pixel image and try catch here to check :(
+    
+    SDGraphicsImageRenderer *renderer = [[SDGraphicsImageRenderer alloc] initWithSize:CGSizeMake(1, 1)];
+    @try {
+        __unused UIImage *dummyImage = [renderer imageWithActions:^(CGContextRef  _Nonnull context) {
+            // WARNING! Some CoreSVG exceptions can be catched, but not always
+            // If you finally crash here (un-catchable), you can only workaround (or hope Apple fix this)
+            // Change your code to use `SDWebImageContextImageThumbnailPixelSize` context option with enough size to render bitmap SVG instead
+            [image drawInRect:CGRectMake(0, 0, 1, 1)];
+        }];
+    } @catch (...) {
+        // CoreSVG decode failed
+        return nil;
+    }
+    
     return image;
 }