NetBSD/usr.bin/mail/popen.c

424 lines
8.5 KiB
C
Raw Normal View History

/* $NetBSD: popen.c,v 1.17 2003/08/07 11:14:40 agc Exp $ */
1993-03-21 12:45:37 +03:00
/*
1994-06-29 09:09:04 +04:00
* Copyright (c) 1980, 1993
* The Regents of the University of California. All rights reserved.
1993-03-21 12:45:37 +03:00
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
1993-03-21 12:45:37 +03:00
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
1993-03-21 12:45:37 +03:00
#ifndef lint
#if 0
static char sccsid[] = "@(#)popen.c 8.1 (Berkeley) 6/6/93";
#else
__RCSID("$NetBSD: popen.c,v 1.17 2003/08/07 11:14:40 agc Exp $");
#endif
1993-03-21 12:45:37 +03:00
#endif /* not lint */
#include "rcv.h"
#include <sys/wait.h>
#include <fcntl.h>
#include <errno.h>
#include <stdarg.h>
1994-06-29 09:09:04 +04:00
#include "extern.h"
1993-03-21 12:45:37 +03:00
#define READ 0
#define WRITE 1
struct fp {
FILE *fp;
int pipe;
pid_t pid;
1993-03-21 12:45:37 +03:00
struct fp *link;
};
static struct fp *fp_head;
1994-06-29 09:09:04 +04:00
struct child {
pid_t pid;
1994-06-29 09:09:04 +04:00
char done;
char free;
1998-12-19 19:34:04 +03:00
int status;
1994-06-29 09:09:04 +04:00
struct child *link;
};
static struct child *child, *child_freelist = NULL;
static struct child *findchild(pid_t, int);
2002-03-02 17:59:35 +03:00
static void delchild(struct child *);
static pid_t file_pid(FILE *);
static pid_t start_commandv(char *, sigset_t *, int, int, va_list);
1994-06-29 09:09:04 +04:00
1993-03-21 12:45:37 +03:00
FILE *
2002-03-02 18:27:51 +03:00
Fopen(char *fn, char *mode)
1993-03-21 12:45:37 +03:00
{
FILE *fp;
2002-03-02 18:27:51 +03:00
if ((fp = fopen(fn, mode)) != NULL) {
1994-06-29 09:09:04 +04:00
register_file(fp, 0, 0);
2002-03-06 00:18:14 +03:00
(void)fcntl(fileno(fp), F_SETFD, 1);
1994-06-29 09:09:04 +04:00
}
1993-03-21 12:45:37 +03:00
return fp;
}
FILE *
2002-03-02 17:59:35 +03:00
Fdopen(int fd, char *mode)
1993-03-21 12:45:37 +03:00
{
FILE *fp;
1994-06-29 09:09:04 +04:00
if ((fp = fdopen(fd, mode)) != NULL) {
register_file(fp, 0, 0);
2002-03-06 00:18:14 +03:00
(void)fcntl(fileno(fp), F_SETFD, 1);
1994-06-29 09:09:04 +04:00
}
1993-03-21 12:45:37 +03:00
return fp;
}
1994-06-29 09:09:04 +04:00
int
2002-03-02 17:59:35 +03:00
Fclose(FILE *fp)
1993-03-21 12:45:37 +03:00
{
1993-03-21 12:45:37 +03:00
unregister_file(fp);
return fclose(fp);
}
FILE *
2002-03-02 17:59:35 +03:00
Popen(char *cmd, char *mode)
1993-03-21 12:45:37 +03:00
{
int p[2];
int myside, hisside, fd0, fd1;
pid_t pid;
sigset_t nset;
1993-03-21 12:45:37 +03:00
FILE *fp;
if (pipe(p) < 0)
return NULL;
2002-03-06 00:18:14 +03:00
(void)fcntl(p[READ], F_SETFD, 1);
(void)fcntl(p[WRITE], F_SETFD, 1);
1993-03-21 12:45:37 +03:00
if (*mode == 'r') {
myside = p[READ];
hisside = fd0 = fd1 = p[WRITE];
1993-03-21 12:45:37 +03:00
} else {
myside = p[WRITE];
hisside = fd0 = p[READ];
fd1 = -1;
}
sigemptyset(&nset);
pid = start_command(value("SHELL"), &nset, fd0, fd1, "-c", cmd, NULL);
if (pid < 0) {
(void)close(p[READ]);
(void)close(p[WRITE]);
1993-03-21 12:45:37 +03:00
return NULL;
}
2002-03-06 00:18:14 +03:00
(void)close(hisside);
1993-03-21 12:45:37 +03:00
if ((fp = fdopen(myside, mode)) != NULL)
1994-06-29 09:09:04 +04:00
register_file(fp, 1, pid);
1993-03-21 12:45:37 +03:00
return fp;
}
1994-06-29 09:09:04 +04:00
int
2002-03-02 17:59:35 +03:00
Pclose(FILE *ptr)
1993-03-21 12:45:37 +03:00
{
int i;
sigset_t nset, oset;
1993-03-21 12:45:37 +03:00
1994-06-29 09:09:04 +04:00
i = file_pid(ptr);
1993-03-21 12:45:37 +03:00
unregister_file(ptr);
2002-03-06 00:18:14 +03:00
(void)fclose(ptr);
sigemptyset(&nset);
sigaddset(&nset, SIGINT);
sigaddset(&nset, SIGHUP);
sigprocmask(SIG_BLOCK, &nset, &oset);
1994-06-29 09:09:04 +04:00
i = wait_child(i);
sigprocmask(SIG_SETMASK, &oset, NULL);
1993-03-21 12:45:37 +03:00
return i;
}
1994-06-29 09:09:04 +04:00
void
2002-03-02 17:59:35 +03:00
close_all_files(void)
1993-03-21 12:45:37 +03:00
{
while (fp_head)
if (fp_head->pipe)
2002-03-06 00:18:14 +03:00
(void)Pclose(fp_head->fp);
1993-03-21 12:45:37 +03:00
else
2002-03-06 00:18:14 +03:00
(void)Fclose(fp_head->fp);
1993-03-21 12:45:37 +03:00
}
1994-06-29 09:09:04 +04:00
void
register_file(FILE *fp, int pipefd, pid_t pid)
1993-03-21 12:45:37 +03:00
{
struct fp *fpp;
if ((fpp = (struct fp *)malloc(sizeof(*fpp))) == NULL)
errx(1, "Out of memory");
1993-03-21 12:45:37 +03:00
fpp->fp = fp;
2002-03-02 18:27:51 +03:00
fpp->pipe = pipefd;
1994-06-29 09:09:04 +04:00
fpp->pid = pid;
1993-03-21 12:45:37 +03:00
fpp->link = fp_head;
fp_head = fpp;
}
1994-06-29 09:09:04 +04:00
void
2002-03-02 17:59:35 +03:00
unregister_file(FILE *fp)
1993-03-21 12:45:37 +03:00
{
struct fp **pp, *p;
for (pp = &fp_head; (p = *pp) != NULL; pp = &p->link)
1993-03-21 12:45:37 +03:00
if (p->fp == fp) {
*pp = p->link;
(void)free(p);
1993-03-21 12:45:37 +03:00
return;
}
errx(1, "Invalid file pointer");
1994-06-29 09:09:04 +04:00
}
static pid_t
2002-03-02 17:59:35 +03:00
file_pid(FILE *fp)
1994-06-29 09:09:04 +04:00
{
struct fp *p;
for (p = fp_head; p; p = p->link)
if (p->fp == fp)
return p->pid;
errx(1, "Invalid file pointer");
1994-06-29 09:09:04 +04:00
/*NOTREACHED*/
1993-03-21 12:45:37 +03:00
}
/*
* Run a command without a shell, with optional arguments and splicing
* of stdin (-1 means none) and stdout. The command name can be a sequence
* of words.
1993-03-21 12:45:37 +03:00
* Signals must be handled by the caller.
* "nset" contains the signals to ignore in the new process.
* SIGINT is enabled unless it's in "nset".
1993-03-21 12:45:37 +03:00
*/
static pid_t
start_commandv(char *cmd, sigset_t *nset, int infd, int outfd, va_list args)
1993-03-21 12:45:37 +03:00
{
pid_t pid;
1993-03-21 12:45:37 +03:00
if ((pid = fork()) < 0) {
2002-03-06 00:29:30 +03:00
warn("fork");
1993-03-21 12:45:37 +03:00
return -1;
}
if (pid == 0) {
char *argv[100];
int i = getrawlist(cmd, argv, sizeof(argv)/ sizeof(*argv));
1993-03-21 12:45:37 +03:00
while ((argv[i++] = va_arg(args, char *)))
;
argv[i] = NULL;
prepare_child(nset, infd, outfd);
1993-03-21 12:45:37 +03:00
execvp(argv[0], argv);
2002-03-06 00:29:30 +03:00
warn("%s", argv[0]);
1993-03-21 12:45:37 +03:00
_exit(1);
}
return pid;
}
int
run_command(char *cmd, sigset_t *nset, int infd, int outfd, ...)
{
pid_t pid;
va_list args;
va_start(args, outfd);
pid = start_commandv(cmd, nset, infd, outfd, args);
va_end(args);
if (pid < 0)
return -1;
return wait_command(pid);
}
int
start_command(char *cmd, sigset_t *nset, int infd, int outfd, ...)
{
va_list args;
int r;
va_start(args, outfd);
r = start_commandv(cmd, nset, infd, outfd, args);
va_end(args);
return r;
}
1994-06-29 09:09:04 +04:00
void
2002-03-02 17:59:35 +03:00
prepare_child(sigset_t *nset, int infd, int outfd)
1993-03-21 12:45:37 +03:00
{
int i;
sigset_t eset;
1993-03-21 12:45:37 +03:00
1994-06-29 09:09:04 +04:00
/*
* All file descriptors other than 0, 1, and 2 are supposed to be
* close-on-exec.
*/
if (infd > 0) {
1993-03-21 12:45:37 +03:00
dup2(infd, 0);
} else if (infd != 0) {
/* we don't want the child stealing my stdin input */
close(0);
open(_PATH_DEVNULL, O_RDONLY, 0);
}
if (outfd >= 0 && outfd != 1)
1993-03-21 12:45:37 +03:00
dup2(outfd, 1);
if (nset == NULL)
return;
if (nset != NULL) {
for (i = 1; i < NSIG; i++)
if (sigismember(nset, i))
(void)signal(i, SIG_IGN);
}
if (nset == NULL || !sigismember(nset, SIGINT))
2002-03-06 00:18:14 +03:00
(void)signal(SIGINT, SIG_DFL);
sigemptyset(&eset);
2002-03-06 00:18:14 +03:00
(void)sigprocmask(SIG_SETMASK, &eset, NULL);
1993-03-21 12:45:37 +03:00
}
1994-06-29 09:09:04 +04:00
int
wait_command(pid_t pid)
1993-03-21 12:45:37 +03:00
{
if (wait_child(pid) < 0) {
puts("Fatal error in process.");
1993-03-21 12:45:37 +03:00
return -1;
}
return 0;
}
1994-06-29 09:09:04 +04:00
static struct child *
findchild(pid_t pid, int dont_alloc)
1993-03-21 12:45:37 +03:00
{
struct child **cpp;
1993-03-21 12:45:37 +03:00
for (cpp = &child; *cpp != NULL && (*cpp)->pid != pid;
cpp = &(*cpp)->link)
;
if (*cpp == NULL) {
if (dont_alloc)
return NULL;
if (child_freelist) {
*cpp = child_freelist;
child_freelist = (*cpp)->link;
} else {
*cpp = (struct child *)malloc(sizeof(struct child));
if (*cpp == NULL)
errx(1, "Out of memory");
}
1993-03-21 12:45:37 +03:00
(*cpp)->pid = pid;
(*cpp)->done = (*cpp)->free = 0;
(*cpp)->link = NULL;
}
return *cpp;
}
1994-06-29 09:09:04 +04:00
static void
2002-03-02 17:59:35 +03:00
delchild(struct child *cp)
1993-03-21 12:45:37 +03:00
{
struct child **cpp;
1993-03-21 12:45:37 +03:00
for (cpp = &child; *cpp != cp; cpp = &(*cpp)->link)
;
*cpp = cp->link;
cp->link = child_freelist;
child_freelist = cp;
1993-03-21 12:45:37 +03:00
}
void
2002-03-02 17:59:35 +03:00
sigchild(int signo)
1993-03-21 12:45:37 +03:00
{
pid_t pid;
1998-12-19 19:34:04 +03:00
int status;
struct child *cp;
int save_errno = errno;
1993-03-21 12:45:37 +03:00
while ((pid =
waitpid((pid_t)-1, &status, WNOHANG)) > 0) {
cp = findchild(pid, 1);
if (!cp)
continue;
1993-03-21 12:45:37 +03:00
if (cp->free)
delchild(cp);
else {
cp->done = 1;
cp->status = status;
}
}
errno = save_errno;
1993-03-21 12:45:37 +03:00
}
1998-12-19 19:34:04 +03:00
int wait_status;
1993-03-21 12:45:37 +03:00
/*
* Wait for a specific child to die.
*/
1994-06-29 09:09:04 +04:00
int
wait_child(pid_t pid)
1993-03-21 12:45:37 +03:00
{
struct child *cp;
sigset_t nset, oset;
pid_t rv = 0;
sigemptyset(&nset);
sigaddset(&nset, SIGCHLD);
sigprocmask(SIG_BLOCK, &nset, &oset);
/*
* If we have not already waited on the pid (via sigchild)
* wait on it now. Otherwise, use the wait status stashed
* by sigchild.
*/
cp = findchild(pid, 1);
if (cp == NULL || !cp->done)
rv = waitpid(pid, &wait_status, 0);
else
wait_status = cp->status;
if (cp != NULL)
delchild(cp);
sigprocmask(SIG_SETMASK, &oset, NULL);
if (rv == -1 || (WIFEXITED(wait_status) && WEXITSTATUS(wait_status)))
return -1;
else
return 0;
1993-03-21 12:45:37 +03:00
}
/*
* Mark a child as don't care.
*/
1994-06-29 09:09:04 +04:00
void
free_child(pid_t pid)
1993-03-21 12:45:37 +03:00
{
struct child *cp;
sigset_t nset, oset;
sigemptyset(&nset);
sigaddset(&nset, SIGCHLD);
sigprocmask(SIG_BLOCK, &nset, &oset);
if ((cp = findchild(pid, 0)) != NULL) {
if (cp->done)
delchild(cp);
else
cp->free = 1;
}
sigprocmask(SIG_SETMASK, &oset, NULL);
1993-03-21 12:45:37 +03:00
}