From 7fe250a19749a259782b98a26ce17085de7d6976 Mon Sep 17 00:00:00 2001
From: Josh Fried <joshuafried@gmail.com>
Date: Sat, 22 Jun 2024 21:00:03 -0400
Subject: [PATCH] close-on-exec fixes

---
 junction/fs/file.cc          | 12 ++++++++----
 junction/fs/file.h           |  2 +-
 junction/fs/procfs/procfs.cc |  2 +-
 3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/junction/fs/file.cc b/junction/fs/file.cc
index f7ab9d9..982ebf0 100644
--- a/junction/fs/file.cc
+++ b/junction/fs/file.cc
@@ -84,7 +84,7 @@ std::shared_ptr<File> FileTable::Dup(int fd) {
   return tbl->files[fd];
 }
 
-int FileTable::Insert(std::shared_ptr<File> f, size_t lowest, bool cloexec) {
+int FileTable::Insert(std::shared_ptr<File> f, bool cloexec, size_t lowest) {
   rt::SpinGuard g(lock_);
   size_t i;
   auto fin = finally([this, cloexec, &i] {
@@ -567,13 +567,17 @@ long usys_fcntl(int fd, unsigned int cmd, unsigned long arg) {
       std::shared_ptr<File> fdup;
       fdup = ftbl.Dup(fd);
       if (!fdup) return -EBADF;
-      return ftbl.Insert(std::move(fdup), arg, cmd == F_DUPFD_CLOEXEC);
+      return ftbl.Insert(std::move(fdup), cmd == F_DUPFD_CLOEXEC, arg);
     }
     case F_GETFD:
       return ftbl.TestCloseOnExec(fd) ? FD_CLOEXEC : 0;
     case F_SETFD:
-      if (arg != FD_CLOEXEC) return -EINVAL;
-      ftbl.SetCloseOnExec(fd);
+      if (arg == FD_CLOEXEC)
+        ftbl.SetCloseOnExec(fd);
+      else if (arg == 0)
+        ftbl.ClearCloseOnExec(fd);
+      else
+        return -EINVAL;
       return 0;
     case F_GETFL:
       return ToFlags(f->get_mode()) | f->get_flags();
diff --git a/junction/fs/file.h b/junction/fs/file.h
index a8e58c0..3f46cac 100644
--- a/junction/fs/file.h
+++ b/junction/fs/file.h
@@ -356,7 +356,7 @@ class FileTable {
   std::shared_ptr<File> Dup(int fd);
 
   // Inserts a file into the file table and refcounts it. Returns the fd number.
-  int Insert(std::shared_ptr<File> f, size_t lowest = 0, bool cloexec = false);
+  int Insert(std::shared_ptr<File> f, bool cloexec = false, size_t lowest = 0);
 
   // Inserts a file into the file table at a specific fd number and refcounts
   // it. If a file already exists for the fd number, it will be replaced
diff --git a/junction/fs/procfs/procfs.cc b/junction/fs/procfs/procfs.cc
index a8a3020..7047453 100644
--- a/junction/fs/procfs/procfs.cc
+++ b/junction/fs/procfs/procfs.cc
@@ -68,7 +68,7 @@ class ProcFSInode : public Inode {
   std::shared_ptr<IDir> parent_;
 };
 
-constexpr std::optional<pid_t> ParsePid(std::string_view s) {
+std::optional<pid_t> ParsePid(std::string_view s) {
   pid_t result;
   if (std::from_chars(s.data(), s.data() + s.size(), result).ec == std::errc{})
     return result;