view_compiler.cpp: clean up file descriptor handling
For file descriptors which are explicitly passed across an exec()
boundary, mark them as // NOLINT(android-cloexec-open). This suppresses
clang-tidy link checks (intended to be added as part of b/129350825)
Don't call close(STDOUT_FILENO). The dup2() syscall atomically closes
this for us, so we don't need to do it ourselves. Additionally, this
also fixes a race condition where another thread may call open() and get
an FD corresponding to STDOUT_FILENO, which we will then close as part
of the dup2() call. Removing the close() makes file descriptor handling
atomic.
Set O_CLOEXEC on outfd. The pre-duped file descriptor should have
O_CLOEXEC set on it. Calling dup2() will dup the file descriptor, but
NOT preserve the O_CLOEXEC flag. Quoting "man dup2":
The two file descriptors do not share file descriptor flags
(the close-on-exec flag). The close-on-exec flag (FD_CLOEXEC;
see fcntl(2)) for the duplicate descriptor is off.
If we don't set the O_CLOEXEC flag on outfd, we'll be leaking the file
descriptor twice, once as STDOUT_FILENO, and once as outfd. The second
leak is undesirable although harmless.
Additional cleanup: Add missing newlines at end of file.
Bug: 129350825
Test: compiles
Change-Id: Ic83ad72ef8a38106ad95ec0202c5c09c61fcf3e7
diff --git a/cmds/installd/view_compiler.h b/cmds/installd/view_compiler.h
index f7c6e57..aa141ca 100644
--- a/cmds/installd/view_compiler.h
+++ b/cmds/installd/view_compiler.h
@@ -26,4 +26,4 @@
} // namespace installd
} // namespace android
-#endif // VIEW_COMPILER_H_
\ No newline at end of file
+#endif // VIEW_COMPILER_H_