Fix a race condition in llvm::sys::path::unique_file: when we end up
failing to create the unique file because the path doesn't exist,
don't fail if someone else manages to create the path before we do.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172032 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Unix/PathV2.inc b/lib/Support/Unix/PathV2.inc
index 25712a8..741f44a 100644
--- a/lib/Support/Unix/PathV2.inc
+++ b/lib/Support/Unix/PathV2.inc
@@ -421,11 +421,12 @@
rety_open_create:
int RandomFD = ::open(RandomPath.c_str(), O_RDWR | O_CREAT | O_EXCL, mode);
if (RandomFD == -1) {
+ int SavedErrno = errno;
// If the file existed, try again, otherwise, error.
- if (errno == errc::file_exists)
+ if (SavedErrno == errc::file_exists)
goto retry_random_path;
// If path prefix doesn't exist, try to create it.
- if (errno == errc::no_such_file_or_directory &&
+ if (SavedErrno == errc::no_such_file_or_directory &&
!exists(path::parent_path(RandomPath))) {
StringRef p(RandomPath);
SmallString<64> dir_to_create;
@@ -440,13 +441,15 @@
(*i)[1] == '/' &&
(*i)[2] != '/')
return make_error_code(errc::no_such_file_or_directory);
- if (::mkdir(dir_to_create.c_str(), 0700) == -1)
+ if (::mkdir(dir_to_create.c_str(), 0700) == -1 &&
+ errno != errc::file_exists)
return error_code(errno, system_category());
}
}
goto rety_open_create;
}
- return error_code(errno, system_category());
+
+ return error_code(SavedErrno, system_category());
}
// Make the path absolute.