/* Create a pipe, with specific opening flags.
- Copyright (C) 2009 Free Software Foundation, Inc.
+ Copyright (C) 2009-2013 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
- with this program; if not, write to the Free Software Foundation,
- Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+ with this program; if not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
#include <errno.h>
#include <fcntl.h>
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
-/* Native Woe32 API. */
+#include "binary-io.h"
+#include "verify.h"
-# include <io.h>
+#if GNULIB_defined_O_NONBLOCK
+# include "nonblocking.h"
+#endif
-#else
-/* Unix API. */
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+/* Native Windows API. */
-# ifndef O_CLOEXEC
-# define O_CLOEXEC 0
-# endif
+# include <io.h>
#endif
int
pipe2 (int fd[2], int flags)
{
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
-/* Native Woe32 API. */
+ /* Mingw _pipe() corrupts fd on failure; also, if we succeed at
+ creating the pipe but later fail at changing fcntl, we want
+ to leave fd unchanged: http://austingroupbugs.net/view.php?id=467 */
+ int tmp[2];
+ tmp[0] = fd[0];
+ tmp[1] = fd[1];
+
+#if HAVE_PIPE2
+# undef pipe2
+ /* Try the system call first, if it exists. (We may be running with a glibc
+ that has the function but with an older kernel that lacks it.) */
+ {
+ /* Cache the information whether the system call really exists. */
+ static int have_pipe2_really; /* 0 = unknown, 1 = yes, -1 = no */
+ if (have_pipe2_really >= 0)
+ {
+ int result = pipe2 (fd, flags);
+ if (!(result < 0 && errno == ENOSYS))
+ {
+ have_pipe2_really = 1;
+ return result;
+ }
+ have_pipe2_really = -1;
+ }
+ }
+#endif
/* Check the supported flags. */
- if ((flags & ~(O_CLOEXEC | O_BINARY | O_TEXT)) != 0)
+ if ((flags & ~(O_CLOEXEC | O_NONBLOCK | O_BINARY | O_TEXT)) != 0)
{
errno = EINVAL;
return -1;
}
- return _pipe (fd, 4096, flags);
-
-#else
-/* Unix API. */
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+/* Native Windows API. */
- /* Check the supported flags. */
- if ((flags & ~(O_CLOEXEC | O_NONBLOCK | O_TEXT | O_BINARY)) != 0)
+ if (_pipe (fd, 4096, flags & ~O_NONBLOCK) < 0)
{
- errno = EINVAL;
+ fd[0] = tmp[0];
+ fd[1] = tmp[1];
return -1;
}
+ /* O_NONBLOCK handling.
+ On native Windows platforms, O_NONBLOCK is defined by gnulib. Use the
+ functions defined by the gnulib module 'nonblocking'. */
+# if GNULIB_defined_O_NONBLOCK
+ if (flags & O_NONBLOCK)
+ {
+ if (set_nonblocking_flag (fd[0], true) != 0
+ || set_nonblocking_flag (fd[1], true) != 0)
+ goto fail;
+ }
+# else
+ {
+ verify (O_NONBLOCK == 0);
+ }
+# endif
+
+ return 0;
+
+#else
+/* Unix API. */
+
if (pipe (fd) < 0)
return -1;
/* POSIX <http://www.opengroup.org/onlinepubs/9699919799/functions/pipe.html>
says that initially, the O_NONBLOCK and FD_CLOEXEC flags are cleared on
- both fd[0] amd fd[1]. */
+ both fd[0] and fd[1]. */
+ /* O_NONBLOCK handling.
+ On Unix platforms, O_NONBLOCK is defined by the system. Use fcntl(). */
if (flags & O_NONBLOCK)
{
int fcntl_flags;
if ((fcntl_flags = fcntl (fd[1], F_GETFL, 0)) < 0
- || fcntl (fd[1], F_SETFL, fcntl_flags | O_NONBLOCK) == -1
- || (fcntl_flags = fcntl (fd[0], F_GETFL, 0)) < 0
- || fcntl (fd[0], F_SETFL, fcntl_flags | O_NONBLOCK) == -1)
- goto fail;
+ || fcntl (fd[1], F_SETFL, fcntl_flags | O_NONBLOCK) == -1
+ || (fcntl_flags = fcntl (fd[0], F_GETFL, 0)) < 0
+ || fcntl (fd[0], F_SETFL, fcntl_flags | O_NONBLOCK) == -1)
+ goto fail;
}
if (flags & O_CLOEXEC)
int fcntl_flags;
if ((fcntl_flags = fcntl (fd[1], F_GETFD, 0)) < 0
- || fcntl (fd[1], F_SETFD, fcntl_flags | FD_CLOEXEC) == -1
- || (fcntl_flags = fcntl (fd[0], F_GETFD, 0)) < 0
- || fcntl (fd[0], F_SETFD, fcntl_flags | FD_CLOEXEC) == -1)
- goto fail;
+ || fcntl (fd[1], F_SETFD, fcntl_flags | FD_CLOEXEC) == -1
+ || (fcntl_flags = fcntl (fd[0], F_GETFD, 0)) < 0
+ || fcntl (fd[0], F_SETFD, fcntl_flags | FD_CLOEXEC) == -1)
+ goto fail;
}
# if O_BINARY
if (flags & O_BINARY)
{
- setmode (fd[1], O_BINARY);
- setmode (fd[0], O_BINARY);
+ set_binary_mode (fd[1], O_BINARY);
+ set_binary_mode (fd[0], O_BINARY);
}
else if (flags & O_TEXT)
{
- setmode (fd[1], O_TEXT);
- setmode (fd[0], O_TEXT);
+ set_binary_mode (fd[1], O_TEXT);
+ set_binary_mode (fd[0], O_TEXT);
}
# endif
return 0;
+#endif
+
+#if GNULIB_defined_O_NONBLOCK || \
+ !((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__)
fail:
{
int saved_errno = errno;
close (fd[0]);
close (fd[1]);
+ fd[0] = tmp[0];
+ fd[1] = tmp[1];
errno = saved_errno;
return -1;
}
-
#endif
}
projects / gnulib.git / blobdiff