Add FileWriteMode::kCreateOrFail

util/file/file_io_posix.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 57 matching lines @@
 }  // namespace
 
 namespace crashpad {
 
 namespace {
 
 FileHandle LoggingOpenFileForOutput(int rdwr_or_wronly,
                                     const base::FilePath& path,
                                     FileWriteMode mode,
                                     FilePermissions permissions) {
-  int flags = rdwr_or_wronly | O_CREAT;
-  // kReuseOrCreate does not need any additional flags.
-  if (mode == FileWriteMode::kTruncateOrCreate)
-    flags |= O_TRUNC;
-  else if (mode == FileWriteMode::kCreateOrFail)
-    flags |= O_EXCL;
+  int flags = rdwr_or_wronly & (O_RDWR | O_WRONLY);
+  DCHECK_NE(flags, 0);
+
+  switch (mode) {
+    case FileWriteMode::kReuseOrFail:
+      break;
+    case FileWriteMode::kReuseOrCreate:
+      flags |= O_CREAT;
+      break;
+    case FileWriteMode::kTruncateOrCreate:
+      flags |= O_CREAT | O_TRUNC;
+      break;
+    case FileWriteMode::kCreateOrFail:
+      flags |= O_CREAT | O_EXCL;
+      break;
+  }
 
   int fd = HANDLE_EINTR(
       open(path.value().c_str(),
            flags,
            permissions == FilePermissions::kWorldReadable ? 0644 : 0600));
   PLOG_IF(ERROR, fd < 0) << "open " << path.value();
   return fd;
 }
 
 }  // namespace
@@ skipping 51 matching lines @@
   return true;
 }
 
 bool LoggingCloseFile(FileHandle file) {
   int rv = IGNORE_EINTR(close(file));
   PLOG_IF(ERROR, rv != 0) << "close";
   return rv == 0;
 }
 
 }  // namespace crashpad