proto writer: fix created file permissions

Following the change to use protobuf zero copy output streams, files
were being created with no group or other permissions, regardless of
umask. We now pass `0666` to `open(2)`.

PiperOrigin-RevId: 608588716
Change-Id: I92d5bdf98966e063f698ba09d4fd8b3ee258e3f2

1 files changed, 4 insertions, 3 deletions

diff --git a/stg.cc b/stg.cc
index 8c97a6b..c046c3b 100644
--- a/stg.cc
+++ b/stg.cc
@@ -101,9 +101,10 @@ void FilterSymbols(Graph& graph, Id root, const Filter& filter) {
 }
 
 void Write(Runtime& runtime, const Graph& graph, Id root, const char* output) {
-  FileDescriptor output_file_descriptor(output, O_CREAT | O_WRONLY | O_TRUNC,
-                                        S_IRUSR | S_IWUSR);
-  google::protobuf::io::FileOutputStream os(output_file_descriptor.Value());
+  const FileDescriptor output_fd(
+      output, O_CREAT | O_WRONLY | O_TRUNC,
+      S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
+  google::protobuf::io::FileOutputStream os(output_fd.Value());
   {
     const Time x(runtime, "write");
     proto::Writer writer(graph);