From 440bf5bee50a0abca990d69ce12fc2a844bda95c Mon Sep 17 00:00:00 2001 From: Matthias Clasen Date: Fri, 19 Jun 2009 23:44:29 -0400 Subject: [PATCH] Use pipe2 when available This avoids a small window for races between pipe and fdset. Reported in bug 579933 by Thiago Macieira. --- configure.in | 11 ++--------- glib/gmain.c | 20 +++++++++++++++----- 2 files changed, 17 insertions(+), 14 deletions(-) diff --git a/configure.in b/configure.in index d253f60bb..1e070d8a5 100644 --- a/configure.in +++ b/configure.in @@ -559,15 +559,8 @@ AC_HEADER_STDC # Checks for library functions. AC_FUNC_VPRINTF AC_FUNC_ALLOCA -AC_CHECK_FUNCS(mmap) -AC_CHECK_FUNCS(posix_memalign) -AC_CHECK_FUNCS(memalign) -AC_CHECK_FUNCS(valloc) -AC_CHECK_FUNCS(fsync) - -AC_CHECK_FUNCS(atexit on_exit) - -AC_CHECK_FUNCS(timegm gmtime_r) +AC_CHECK_FUNCS(mmap posix_memalign memalign valloc fsync pipe2) +AC_CHECK_FUNCS(atexit on_exit timegm gmtime_r) AC_CHECK_SIZEOF(char) AC_CHECK_SIZEOF(short) diff --git a/glib/gmain.c b/glib/gmain.c index 331c0a86b..6d6b59411 100644 --- a/glib/gmain.c +++ b/glib/gmain.c @@ -46,6 +46,8 @@ #define G_MAIN_POLL_DEBUG #endif +#define _GNU_SOURCE /* for pipe2 */ + #include "glib.h" #include "gthreadprivate.h" #include @@ -402,12 +404,20 @@ g_main_context_init_pipe (GMainContext *context) # ifndef G_OS_WIN32 if (context->wake_up_pipe[0] != -1) return; - if (pipe (context->wake_up_pipe) < 0) - g_error ("Cannot create pipe main loop wake-up: %s\n", - g_strerror (errno)); + +#ifdef HAVE_PIPE2 + /* if this fails, we fall through and try pipe */ + pipe2 (context->wake_up_pipe, O_CLOEXEC); +#endif + if (context->wake_up_pipe[0] == -1) + { + if (pipe (context->wake_up_pipe) < 0) + g_error ("Cannot create pipe main loop wake-up: %s\n", + g_strerror (errno)); - fcntl (context->wake_up_pipe[0], F_SETFD, FD_CLOEXEC); - fcntl (context->wake_up_pipe[1], F_SETFD, FD_CLOEXEC); + fcntl (context->wake_up_pipe[0], F_SETFD, FD_CLOEXEC); + fcntl (context->wake_up_pipe[1], F_SETFD, FD_CLOEXEC); + } context->wake_up_rec.fd = context->wake_up_pipe[0]; context->wake_up_rec.events = G_IO_IN; -- 2.34.1