This might make the fuzzer error debuggable. (simdjson#1345)

lemire · web-flow · commit c90ee572035c · 2020-12-16T18:31:29.000-05:00
diff --git a/fuzz/fuzz_utf8.cpp b/fuzz/fuzz_utf8.cpp
@@ -45,6 +45,12 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
             const bool current=utf8verify(e);
             std::cerr<<e->name()<<" returns "<<current<<std::endl;
         }
+        std::cerr << "Offending input: \"";
+        for(size_t i = 0; i < Size; i++) {
+            std::cerr << "\\x" << std::hex << std::setw(2) << std::setfill('0')  << uint32_t(Data[i]);
+        }
+        std::cerr << "\"" <<std::endl;
+
         std::abort();
     }
 

Original file line number	Diff line number	Diff line change
`@@ -45,6 +45,12 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {`
`45`	`45`	`const bool current=utf8verify(e);`
`46`	`46`	`std::cerr<<e->name()<<" returns "<<current<<std::endl;`
`47`	`47`	`}`
	`48`	`+ std::cerr << "Offending input: \"";`
	`49`	`+ for(size_t i = 0; i < Size; i++) {`
	`50`	`+ std::cerr << "\\x" << std::hex << std::setw(2) << std::setfill('0') << uint32_t(Data[i]);`
	`51`	`+ }`
	`52`	`+ std::cerr << "\"" <<std::endl;`
	`53`	`+`
`48`	`54`	`std::abort();`
`49`	`55`	`}`
`50`	`56`