[libFuzzer] don't print large artifacts to stderr

[oota-llvm.git] / lib / Fuzzer / FuzzerIO.cpp

diff --git a/lib/Fuzzer/FuzzerIO.cpp b/lib/Fuzzer/FuzzerIO.cpp
index 1d25389770fa27f38735fad7894d2189e494fa72..b6ffb752de310dd8afbf78c15d4ce8ee6316894f 100644 (file)
--- a/lib/Fuzzer/FuzzerIO.cpp
+++ b/lib/Fuzzer/FuzzerIO.cpp
@@ -21,10 +21,8 @@ namespace fuzzer {
 
 static long GetEpoch(const std::string &Path) {
   struct stat St;
-  if (stat(Path.c_str(), &St)) {
-    Printf("Can not stat: %s; exiting\n", Path.c_str());
-    exit(1);
-  }
+  if (stat(Path.c_str(), &St))
+    return 0;  // Can't stat, be conservative.
   return St.st_mtime;
 }
 
@@ -32,7 +30,7 @@ static std::vector<std::string> ListFilesInDir(const std::string &Dir,
                                                long *Epoch) {
   std::vector<std::string> V;
   if (Epoch) {
-    auto E = GetEpoch(Dir.c_str());
+    auto E = GetEpoch(Dir);
     if (*Epoch >= E) return V;
     *Epoch = E;
   }
@@ -66,8 +64,11 @@ void CopyFileToErr(const std::string &Path) {
 }
 
 void WriteToFile(const Unit &U, const std::string &Path) {
-  std::ofstream OF(Path);
-  OF.write((const char*)U.data(), U.size());
+  // Use raw C interface because this function may be called from a sig handler.
+  FILE *Out = fopen(Path.c_str(), "w");
+  if (!Out) return;
+  fwrite(U.data(), sizeof(U[0]), U.size(), Out);
+  fclose(Out);
 }
 
 void ReadDirToVectorOfUnits(const char *Path, std::vector<Unit> *V,