1 /* Copyright (C) 1993-2013 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Written by Per Bothner <bothner@cygnus.com>.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>.
19 As a special exception, if you link the code in this file with
20 files compiled with a GNU compiler to produce an executable,
21 that does not cause the resulting executable to be covered by
22 the GNU Lesser General Public License. This exception does not
23 however invalidate any other reasons why the executable file
24 might be covered by the GNU Lesser General Public License.
25 This exception applies to code released by its copyright holders
26 in files containing the exception. */
29 # define _POSIX_SOURCE
37 # include <shlib-compat.h>
38 # include <not-cancel.h>
40 #include <sys/types.h>
42 #include <kernel-features.h>
46 #define _IO_fork __fork
48 #define _IO_fork fork /* defined in libiberty, if needed */
50 extern _IO_pid_t _IO_fork (void) __THROW;
55 #define _IO_dup2 __dup2
59 extern int _IO_dup2 (int fd, int fd2) __THROW;
64 #define _IO_waitpid waitpid_not_cancel
66 #define _IO_waitpid waitpid
71 #define _IO_execl execl
74 #define _IO__exit _exit
79 #define _IO_close close_not_cancel
81 #define _IO_close close
87 struct _IO_FILE_plus file;
88 /* Following fields must match those in class procbuf (procbuf.h) */
90 struct _IO_proc_file *next;
92 typedef struct _IO_proc_file _IO_proc_file;
94 static const struct _IO_jump_t _IO_proc_jumps;
96 static struct _IO_proc_file *proc_file_chain;
99 static _IO_lock_t proc_file_chain_lock = _IO_lock_initializer;
102 unlock (void *not_used)
104 _IO_lock_unlock (proc_file_chain_lock);
109 _IO_new_proc_open (fp, command, mode)
115 int parent_end, child_end;
122 while (*mode != '\0')
136 __set_errno (EINVAL);
140 if ((do_read ^ do_write) == 0)
143 if (_IO_file_is_open (fp))
147 # ifndef __ASSUME_PIPE2
148 if (__have_pipe2 >= 0)
151 int r = __pipe2 (pipe_fds, O_CLOEXEC);
152 # ifndef __ASSUME_PIPE2
153 if (__have_pipe2 == 0)
154 __have_pipe2 = r != -1 || errno != ENOSYS ? 1 : -1;
156 if (__have_pipe2 > 0)
162 #ifndef __ASSUME_PIPE2
164 if (__have_pipe2 < 0)
166 if (__pipe (pipe_fds) < 0)
172 parent_end = pipe_fds[0];
173 child_end = pipe_fds[1];
174 read_or_write = _IO_NO_WRITES;
178 parent_end = pipe_fds[1];
179 child_end = pipe_fds[0];
180 read_or_write = _IO_NO_READS;
183 ((_IO_proc_file *) fp)->pid = child_pid = _IO_fork ();
186 int child_std_end = do_read ? 1 : 0;
187 struct _IO_proc_file *p;
189 #ifndef __ASSUME_PIPE2
190 /* If we have pipe2 the descriptor is marked for close-on-exec. */
191 _IO_close (parent_end);
193 if (child_end != child_std_end)
195 _IO_dup2 (child_end, child_std_end);
196 #ifndef __ASSUME_PIPE2
197 _IO_close (child_end);
203 /* The descriptor is already the one we will use. But it must
204 not be marked close-on-exec. Undo the effects. */
205 # ifndef __ASSUME_PIPE2
206 if (__have_pipe2 > 0)
208 __fcntl (child_end, F_SETFD, 0);
211 /* POSIX.2: "popen() shall ensure that any streams from previous
212 popen() calls that remain open in the parent process are closed
213 in the new child process." */
214 for (p = proc_file_chain; p; p = p->next)
216 int fd = _IO_fileno ((_IO_FILE *) p);
218 /* If any stream from previous popen() calls has fileno
219 child_std_end, it has been already closed by the dup2 syscall
221 if (fd != child_std_end)
225 _IO_execl ("/bin/sh", "sh", "-c", command, (char *) 0);
228 _IO_close (child_end);
231 _IO_close (parent_end);
237 #ifndef __ASSUME_PIPE2
239 if (__have_pipe2 < 0)
241 __fcntl (parent_end, F_SETFD, FD_CLOEXEC);
247 /* Undo the effects of the pipe2 call which set the
248 close-on-exec flag. */
249 # ifndef __ASSUME_PIPE2
250 if (__have_pipe2 > 0)
252 __fcntl (parent_end, F_SETFD, 0);
256 _IO_fileno (fp) = parent_end;
258 /* Link into proc_file_chain. */
260 _IO_cleanup_region_start_noarg (unlock);
261 _IO_lock_lock (proc_file_chain_lock);
263 ((_IO_proc_file *) fp)->next = proc_file_chain;
264 proc_file_chain = (_IO_proc_file *) fp;
266 _IO_lock_unlock (proc_file_chain_lock);
267 _IO_cleanup_region_end (0);
270 _IO_mask_flags (fp, read_or_write, _IO_NO_READS|_IO_NO_WRITES);
275 _IO_new_popen (command, mode)
281 struct _IO_proc_file fpx;
288 new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE));
292 new_f->fpx.file.file._lock = &new_f->lock;
294 fp = &new_f->fpx.file.file;
296 _IO_JUMPS (&new_f->fpx.file) = &_IO_proc_jumps;
297 _IO_new_file_init (&new_f->fpx.file);
298 #if !_IO_UNIFIED_JUMPTABLES
299 new_f->fpx.file.vtable = NULL;
301 if (_IO_new_proc_open (fp, command, mode) != NULL)
302 return (_IO_FILE *) &new_f->fpx.file;
303 _IO_un_link (&new_f->fpx.file);
309 _IO_new_proc_close (fp)
312 /* This is not name-space clean. FIXME! */
314 _IO_proc_file **ptr = &proc_file_chain;
318 /* Unlink from proc_file_chain. */
320 _IO_cleanup_region_start_noarg (unlock);
321 _IO_lock_lock (proc_file_chain_lock);
323 for ( ; *ptr != NULL; ptr = &(*ptr)->next)
325 if (*ptr == (_IO_proc_file *) fp)
333 _IO_lock_unlock (proc_file_chain_lock);
334 _IO_cleanup_region_end (0);
337 if (status < 0 || _IO_close (_IO_fileno(fp)) < 0)
339 /* POSIX.2 Rationale: "Some historical implementations either block
340 or ignore the signals SIGINT, SIGQUIT, and SIGHUP while waiting
341 for the child process to terminate. Since this behavior is not
342 described in POSIX.2, such implementations are not conforming." */
345 wait_pid = _IO_waitpid (((_IO_proc_file *) fp)->pid, &wstatus, 0);
347 while (wait_pid == -1 && errno == EINTR);
353 static const struct _IO_jump_t _IO_proc_jumps = {
355 JUMP_INIT(finish, _IO_new_file_finish),
356 JUMP_INIT(overflow, _IO_new_file_overflow),
357 JUMP_INIT(underflow, _IO_new_file_underflow),
358 JUMP_INIT(uflow, _IO_default_uflow),
359 JUMP_INIT(pbackfail, _IO_default_pbackfail),
360 JUMP_INIT(xsputn, _IO_new_file_xsputn),
361 JUMP_INIT(xsgetn, _IO_default_xsgetn),
362 JUMP_INIT(seekoff, _IO_new_file_seekoff),
363 JUMP_INIT(seekpos, _IO_default_seekpos),
364 JUMP_INIT(setbuf, _IO_new_file_setbuf),
365 JUMP_INIT(sync, _IO_new_file_sync),
366 JUMP_INIT(doallocate, _IO_file_doallocate),
367 JUMP_INIT(read, _IO_file_read),
368 JUMP_INIT(write, _IO_new_file_write),
369 JUMP_INIT(seek, _IO_file_seek),
370 JUMP_INIT(close, _IO_new_proc_close),
371 JUMP_INIT(stat, _IO_file_stat),
372 JUMP_INIT(showmanyc, _IO_default_showmanyc),
373 JUMP_INIT(imbue, _IO_default_imbue)
376 strong_alias (_IO_new_popen, __new_popen)
377 versioned_symbol (libc, _IO_new_popen, _IO_popen, GLIBC_2_1);
378 versioned_symbol (libc, __new_popen, popen, GLIBC_2_1);
379 versioned_symbol (libc, _IO_new_proc_open, _IO_proc_open, GLIBC_2_1);
380 versioned_symbol (libc, _IO_new_proc_close, _IO_proc_close, GLIBC_2_1);