/* Subprocesses with pipes.
Copyright (C) 2002 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
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program 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 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* Written by Paul Eggert
and Florian Krohm . */
#if HAVE_CONFIG_H
# include
#endif
// (BH)
#ifdef MSDOS // For Subpipe
#include // For execv()
#include // For _O_TEXT
#include // For _fileno,stdin,stdout
#include // For _pipe,open,dup2
#define pipe(fd) _pipe(fd,1024*1024*256,_O_TEXT|_O_NOINHERIT)
#endif
#if HAVE_SYS_TYPES_H
# include
#endif
#include
#ifndef errno
extern int errno;
#endif
#include
#if ! defined SIGCHLD && defined SIGCLD
# define SIGCHLD SIGCLD
#endif
#if HAVE_STDLIB_H
# include
#endif
/* The following test is to work around the gross typo in
systems like Sony NEWS-OS Release 4.0C, whereby EXIT_FAILURE
is defined to 0, not 1. */
#if ! EXIT_FAILURE
# undef EXIT_FAILURE
# define EXIT_FAILURE 1
#endif
#if HAVE_UNISTD_H
# include
#endif
#ifndef STDIN_FILENO
# define STDIN_FILENO 0
#endif
#ifndef STDOUT_FILENO
# define STDOUT_FILENO 1
#endif
#if ! HAVE_DUP2 && ! defined dup2
# if HAVE_FCNTL_H
# include
# endif
# define dup2(f, t) (close (t), fcntl (f, F_DUPFD, t))
#endif
#if HAVE_SYS_WAIT_H
# include
#endif
#ifndef WEXITSTATUS
# define WEXITSTATUS(stat_val) ((unsigned int) (stat_val) >> 8)
#endif
#ifndef WIFEXITED
# define WIFEXITED(stat_val) (((stat_val) & 255) == 0)
#endif
#if HAVE_VFORK_H
# include
#endif
#if ! HAVE_WORKING_VFORK
# define vfork fork
#endif
#include "error.h"
#include "gettext.h"
#define _(Msgid) gettext (Msgid)
#include "subpipe.h"
/* Initialize this module. */
void
init_subpipe (void)
{
#ifdef SIGCHLD
/* System V fork+wait does not work if SIGCHLD is ignored. */
signal (SIGCHLD, SIG_DFL);
#endif
}
/* Create a subprocess that is run as a filter. ARGV is the
NULL-terminated argument vector for the subprocess. Store read and
write file descriptors for communication with the subprocess into
FD[0] and FD[1]: input meant for the process can be written into
FD[0], and output from the process can be read from FD[1]. Return
the subprocess id.
To avoid deadlock, the invoker must not let incoming data pile up
in FD[1] while writing data to FD[0]. */
pid_t
create_subpipe (char const * const *argv, int fd[2])
{
int pipe_fd[2];
int from_in_fd;
int from_out_fd;
int to_in_fd;
int to_out_fd;
pid_t pid;
if (pipe (pipe_fd) != 0)
error (EXIT_FAILURE, errno, "pipe");
to_in_fd = pipe_fd[0]; // Read Handle
to_out_fd = pipe_fd[1]; // Write Handle
if (pipe (pipe_fd) != 0)
error (EXIT_FAILURE, errno, "pipe");
from_in_fd = pipe_fd[0]; // Read Handle
from_out_fd = pipe_fd[1]; // Write Handle
// Duplicate stdio file descriptors (next line will close original)
pipe_fd[0] = _dup(_fileno(stdin));
pipe_fd[1] = _dup(_fileno(stdout));
// Duplicate read/write end of pipes to stdio file descriptors
if(_dup2(to_in_fd, _fileno(stdin)) != 0) return 2;
if(_dup2(from_out_fd, _fileno(stdout)) != 0) return 3;
// Close original read/write end of pipes
close(to_in_fd);
close(from_out_fd);
// Spawn process
pid = _spawnv(_P_NOWAITO, argv[0], (const char* const*)&argv[0]); //
if (pid == -1)
{
switch (errno) {
case E2BIG : error (EXIT_FAILURE, errno, "spawnv E2BIG"); break;
case EINVAL : error (EXIT_FAILURE, errno, "spawnv EINVAL"); break;
case ENOENT : error (EXIT_FAILURE, errno, "spawnv ENOENT"); break;
case ENOEXEC : error (EXIT_FAILURE, errno, "spawnv ENOEXEC"); break;
case ENOMEM : error (EXIT_FAILURE, errno, "spawnv ENOMEM"); break;
default : error (EXIT_FAILURE, errno, "spawnv");
}
}
// Duplicate copy of original stdout back into stdout
if(_dup2(pipe_fd[0], _fileno(stdin)) != 0) return 4;
if(_dup2(pipe_fd[1], _fileno(stdout)) != 0) return 5;
// Close duplicate copy of original stdout
close(pipe_fd[0]);
close(pipe_fd[1]);
/* Parent. */
close (to_in_fd);
close (from_out_fd);
fd[0] = to_out_fd;
fd[1] = from_in_fd;
return pid;
}
/* Wait for the subprocess to exit. */
void
reap_subpipe (pid_t pid, char const *program)
{
#if HAVE_WAITPID || defined waitpid
int wstatus;
if (waitpid (pid, &wstatus, 0) < 0)
error (EXIT_FAILURE, errno, "waitpid");
else
{
int status = WIFEXITED (wstatus) ? WEXITSTATUS (wstatus) : -1;
if (status)
error (EXIT_FAILURE, 0,
_(status == 126
? "subsidiary program `%s' could not be invoked"
: status == 127
? "subsidiary program `%s' not found"
: status < 0
? "subsidiary program `%s' failed"
: "subsidiary program `%s' failed (exit status %d)"),
program, status);
}
#endif
}