Add g_unix_open_pipe_internal () for pipes with the close-on-exec flag

Based on the existing g_unix_open_pipe () but for internal use where
returning a raw errno is needed, not a GError.

docs/reference/glib/meson.build

@@ -38,6 +38,7 @@ if get_option('gtk_doc')
     'gutilsprivate.h',
     'gvalgrind.h',
     'dirent.h',
+    'glib-unixprivate.h',
     'glib-visibility.h',
     'gmodule-visibility.h',
   ]

glib/glib-unix.c

@@ -23,12 +23,8 @@
 
 #include "config.h"
 
-/* To make bionic export pipe2() */
-#ifndef _GNU_SOURCE
-#define _GNU_SOURCE 1
-#endif
-
 #include "glib-unix.h"
+#include "glib-unixprivate.h"
 #include "gmain-internal.h"
 
 #include <string.h>
@@ -94,48 +90,13 @@ g_unix_open_pipe (int     *fds,
                   int      flags,
                   GError **error)
 {
-  int ecode;
-
   /* We only support FD_CLOEXEC */
   g_return_val_if_fail ((flags & (FD_CLOEXEC)) == flags, FALSE);
 
-#ifdef HAVE_PIPE2
-  {
-    int pipe2_flags = 0;
-    if (flags & FD_CLOEXEC)
-      pipe2_flags |= O_CLOEXEC;
-    /* Atomic */
-    ecode = pipe2 (fds, pipe2_flags);
-    if (ecode == -1 && errno != ENOSYS)
-      return g_unix_set_error_from_errno (error, errno);
-    else if (ecode == 0)
-      return TRUE;
-    /* Fall through on -ENOSYS, we must be running on an old kernel */
-  }
-#endif
-  ecode = pipe (fds);
-  if (ecode == -1)
+  if (!g_unix_open_pipe_internal (fds,
+                                  (flags & FD_CLOEXEC) != 0))
     return g_unix_set_error_from_errno (error, errno);
 
-  if (flags == 0)
-    return TRUE;
-
-  ecode = fcntl (fds[0], F_SETFD, flags);
-  if (ecode == -1)
-    {
-      int saved_errno = errno;
-      close (fds[0]);
-      close (fds[1]);
-      return g_unix_set_error_from_errno (error, saved_errno);
-    }
-  ecode = fcntl (fds[1], F_SETFD, flags);
-  if (ecode == -1)
-    {
-      int saved_errno = errno;
-      close (fds[0]);
-      close (fds[1]);
-      return g_unix_set_error_from_errno (error, saved_errno);
-    }
   return TRUE;
 }
 

glib/glib-unixprivate.h

@@ -0,0 +1,87 @@
+/* glib-unixprivate.h - Unix specific integration private functions
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __G_UNIXPRIVATE_H__
+#define __G_UNIXPRIVATE_H__
+
+#include "config.h"
+
+#ifndef G_OS_UNIX
+#error "This header may only be used on UNIX"
+#endif
+
+/* To make bionic export pipe2() */
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE 1
+#endif
+
+#include "gmacros.h"
+#include "gtypes.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+G_BEGIN_DECLS
+
+static inline gboolean
+g_unix_open_pipe_internal (int *fds,
+                           gboolean close_on_exec)
+  {
+#ifdef HAVE_PIPE2
+  do
+    {
+      int ecode;
+
+      /* Atomic */
+      ecode = pipe2 (fds, close_on_exec ? O_CLOEXEC : 0);
+      if (ecode == -1 && errno != ENOSYS)
+        return FALSE;
+      else if (ecode == 0)
+        return TRUE;
+      /* Fall through on -ENOSYS, we must be running on an old kernel */
+    }
+  while (FALSE);
+#endif
+
+  if (pipe (fds) == -1)
+    return FALSE;
+
+  if (!close_on_exec)
+    return TRUE;
+
+  if (fcntl (fds[0], F_SETFD, FD_CLOEXEC) == -1 ||
+      fcntl (fds[1], F_SETFD, FD_CLOEXEC) == -1)
+    {
+      int saved_errno = errno;
+
+      close (fds[0]);
+      close (fds[1]);
+      fds[0] = -1;
+      fds[1] = -1;
+
+      errno = saved_errno;
+      return FALSE;
+    }
+
+  return TRUE;
+}
+
+G_END_DECLS
+
+#endif  /* __G_UNIXPRIVATE_H__ */

glib/meson.build

@@ -365,7 +365,7 @@ if host_system == 'windows'
     glib_sources += files('dirent/wdirent.c')
   endif
 else
-  glib_sources += files('glib-unix.c', 'gspawn.c', 'giounix.c')
+  glib_sources += files('glib-unix.c', 'glib-unixprivate.h', 'gspawn.c', 'giounix.c')
   platform_deps = []
 endif