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authorUlrich Drepper <drepper@redhat.com>2008-07-27 18:26:13 +0000
committerUlrich Drepper <drepper@redhat.com>2008-07-27 18:26:13 +0000
commitd6e0c2a67dbdb3f940d60f68bbcf58a5bdee4a97 (patch)
tree80154bbf66005a9d32db583091847ec051519012 /libio/iopopen.c
parent11ed3eaed92bf9e04925ec50a696eda5b6df0c33 (diff)
downloadglibc-d6e0c2a67dbdb3f940d60f68bbcf58a5bdee4a97.tar.gz
* sysdeps/unix/sysv/linux/syscalls.list: Add __pipe2 alias.
* io/pipe2.c: Likewise. * sysdeps/unix/sysv/linux/kernel-features.h: Define __ASSUME_PIPE2 instead of __ASSUME_PACCEPT. * include/unistd.h: Declare __have_pipe2. * libio/iopopen.c: Implement "e" flag. * libio/Makefile (tests): Add tst-popen1. * libio/tst-popen1.c: New file.
Diffstat (limited to 'libio/iopopen.c')
-rw-r--r--libio/iopopen.c115
1 files changed, 93 insertions, 22 deletions
diff --git a/libio/iopopen.c b/libio/iopopen.c
index d5c6305b09..0ea7c2317b 100644
--- a/libio/iopopen.c
+++ b/libio/iopopen.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1993, 1997-2002, 2003, 2004, 2007
+/* Copyright (C) 1993, 1997-2002, 2003, 2004, 2007, 2008
Free Software Foundation, Inc.
This file is part of the GNU C Library.
Written by Per Bothner <bothner@cygnus.com>.
@@ -56,15 +56,6 @@ extern _IO_pid_t _IO_fork (void) __THROW;
#endif /* _IO_HAVE_SYS_WAIT */
-#ifndef _IO_pipe
-#ifdef _LIBC
-#define _IO_pipe __pipe
-#else
-#define _IO_pipe pipe
-#endif
-extern int _IO_pipe (int des[2]) __THROW;
-#endif
-
#ifndef _IO_dup2
#ifdef _LIBC
#define _IO_dup2 __dup2
@@ -131,41 +122,99 @@ _IO_new_proc_open (fp, command, mode)
volatile int parent_end, child_end;
int pipe_fds[2];
_IO_pid_t child_pid;
+
+ int do_read = 0;
+ int do_write = 0;
+ int do_cloexec = 0;
+ while (*mode != '\0')
+ switch (*mode++)
+ {
+ case 'r':
+ do_read = 1;
+ break;
+ case 'w':
+ do_write = 1;
+ break;
+ case 'e':
+ do_cloexec = 1;
+ break;
+ default:
+ errout:
+ __set_errno (EINVAL);
+ return NULL;
+ }
+
+ if ((do_read ^ do_write) == 0)
+ goto errout;
+
if (_IO_file_is_open (fp))
return NULL;
- if (_IO_pipe (pipe_fds) < 0)
- return NULL;
- if (mode[0] == 'r' && mode[1] == '\0')
+
+#ifdef O_CLOEXEC
+# ifndef __ASSUME_PIPE2
+ if (__have_pipe2 >= 0)
+# endif
+ {
+ int r = __pipe2 (pipe_fds, O_CLOEXEC);
+# ifndef __ASSUME_PIPE2
+ if (__have_pipe2 == 0)
+ __have_pipe2 = r != -1 || errno != ENOSYS ? 1 : -1;
+
+ if (__have_pipe2 > 0)
+# endif
+ if (r < 0)
+ return NULL;
+ }
+#endif
+#ifndef __ASSUME_PIPE2
+# ifdef O_CLOEXEC
+ if (__have_pipe2 < 0)
+# endif
+ if (__pipe (pipe_fds) < 0)
+ return NULL;
+#endif
+
+ if (do_read)
{
parent_end = pipe_fds[0];
child_end = pipe_fds[1];
read_or_write = _IO_NO_WRITES;
}
- else if (mode[0] == 'w' && mode[1] == '\0')
+ else
{
parent_end = pipe_fds[1];
child_end = pipe_fds[0];
read_or_write = _IO_NO_READS;
}
- else
- {
- _IO_close (pipe_fds[0]);
- _IO_close (pipe_fds[1]);
- __set_errno (EINVAL);
- return NULL;
- }
+
((_IO_proc_file *) fp)->pid = child_pid = _IO_fork ();
if (child_pid == 0)
{
- int child_std_end = mode[0] == 'r' ? 1 : 0;
+ int child_std_end = do_read ? 1 : 0;
struct _IO_proc_file *p;
+#ifndef __ASSUME_PIPE2
+ /* If we have pipe2 the descriptor is marked for close-on-exec. */
_IO_close (parent_end);
+#endif
if (child_end != child_std_end)
{
_IO_dup2 (child_end, child_std_end);
+#ifndef __ASSUME_PIPE2
_IO_close (child_end);
+#endif
+ }
+#ifdef O_CLOEXEC
+ else
+ {
+ /* The descriptor is already the one we will use. But it must
+ not be marked close-on-exec. Undo the effects. */
+# ifndef __ASSUME_PIPE2
+ if (__have_pipe2 > 0)
+# endif
+ __fcntl (child_end, F_SETFD, 0);
}
+#endif
/* POSIX.2: "popen() shall ensure that any streams from previous
popen() calls that remain open in the parent process are closed
in the new child process." */
@@ -189,6 +238,28 @@ _IO_new_proc_open (fp, command, mode)
_IO_close (parent_end);
return NULL;
}
+
+ if (do_cloexec)
+ {
+#ifndef __ASSUME_PIPE2
+# ifdef O_CLOEXEC
+ if (__have_pipe2 < 0)
+# endif
+ __fcntl (parent_end, F_SETFD, FD_CLOEXEC);
+#endif
+ }
+ else
+ {
+#ifdef O_CLOEXEC
+ /* Undo the effects of the pipe2 call which set the
+ close-on-exec flag. */
+# ifndef __ASSUME_PIPE2
+ if (__have_pipe2 > 0)
+# endif
+ __fcntl (parent_end, F_SETFD, 0);
+#endif
+ }
+
_IO_fileno (fp) = parent_end;
/* Link into proc_file_chain. */