Fix performance problem in fuzzer.

Author: kevinbackhouse

fuzz/fuzz-read-print-write.cpp

@@ -21,16 +21,22 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
 
     image->readMetadata();
     for (auto& md : image->exifData()) {
-      md.print();
-      md.print(&image->exifData());
+      if (md.tagName().substr(0, 2) != "0x") {
+        md.print();
+        md.print(&image->exifData());
+      }
     }
     for (auto& md : image->iptcData()) {
-      md.print();
-      md.print(&image->exifData());
+      if (md.tagName().substr(0, 2) != "0x") {
+        md.print();
+        md.print(&image->exifData());
+      }
     }
     for (auto& md : image->xmpData()) {
-      md.print();
-      md.print(&image->exifData());
+      if (md.tagName().substr(0, 2) != "0x") {
+        md.print();
+        md.print(&image->exifData());
+      }
     }
 
     // Print to a std::ostringstream so that the fuzzer doesn't