[libFUzzer] change the way we load the seed corpora: instead of loading all files and these executing all files, load and execute them one-by-one. This should reduce the memory usage in many cases

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk/lib/fuzzer@312033 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/FuzzerIOPosix.cpp b/FuzzerIOPosix.cpp
index d642b34..2c452a7 100644
--- a/FuzzerIOPosix.cpp
+++ b/FuzzerIOPosix.cpp
@@ -32,6 +32,13 @@
   return S_ISREG(St.st_mode);
 }
 
+size_t FileSize(const std::string &Path) {
+  struct stat St;
+  if (stat(Path.c_str(), &St))
+    return 0;
+  return St.st_size;
+}
+
 void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
                              Vector<std::string> *V, bool TopDir) {
   auto E = GetEpoch(Dir);