1*8a16b7a1SPedro F. Giffuni /*- 2*8a16b7a1SPedro F. Giffuni * SPDX-License-Identifier: BSD-3-Clause 3*8a16b7a1SPedro F. Giffuni * 458f0484fSRodney W. Grimes * Copyright (c) 1988, 1993 558f0484fSRodney W. Grimes * The Regents of the University of California. All rights reserved. 658f0484fSRodney W. Grimes * 758f0484fSRodney W. Grimes * This code is derived from software written by Ken Arnold and 858f0484fSRodney W. Grimes * published in UNIX Review, Vol. 6, No. 8. 958f0484fSRodney W. Grimes * 1058f0484fSRodney W. Grimes * Redistribution and use in source and binary forms, with or without 1158f0484fSRodney W. Grimes * modification, are permitted provided that the following conditions 1258f0484fSRodney W. Grimes * are met: 1358f0484fSRodney W. Grimes * 1. Redistributions of source code must retain the above copyright 1458f0484fSRodney W. Grimes * notice, this list of conditions and the following disclaimer. 1558f0484fSRodney W. Grimes * 2. Redistributions in binary form must reproduce the above copyright 1658f0484fSRodney W. Grimes * notice, this list of conditions and the following disclaimer in the 1758f0484fSRodney W. Grimes * documentation and/or other materials provided with the distribution. 18fbbd9655SWarner Losh * 3. Neither the name of the University nor the names of its contributors 1958f0484fSRodney W. Grimes * may be used to endorse or promote products derived from this software 2058f0484fSRodney W. Grimes * without specific prior written permission. 2158f0484fSRodney W. Grimes * 2258f0484fSRodney W. Grimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 2358f0484fSRodney W. Grimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2458f0484fSRodney W. Grimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2558f0484fSRodney W. Grimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2658f0484fSRodney W. Grimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2758f0484fSRodney W. Grimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2858f0484fSRodney W. Grimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2958f0484fSRodney W. Grimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 3058f0484fSRodney W. Grimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 3158f0484fSRodney W. Grimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3258f0484fSRodney W. Grimes * SUCH DAMAGE. 3358f0484fSRodney W. Grimes */ 3458f0484fSRodney W. Grimes 3558f0484fSRodney W. Grimes #if defined(LIBC_SCCS) && !defined(lint) 36adf6ad9eSPeter Wemm static char sccsid[] = "@(#)popen.c 8.3 (Berkeley) 5/3/95"; 3758f0484fSRodney W. Grimes #endif /* LIBC_SCCS and not lint */ 3822626efaSDavid E. O'Brien #include <sys/cdefs.h> 3922626efaSDavid E. O'Brien __FBSDID("$FreeBSD$"); 4058f0484fSRodney W. Grimes 41d201fe46SDaniel Eischen #include "namespace.h" 4258f0484fSRodney W. Grimes #include <sys/param.h> 437e7f7ca3SEd Schouten #include <sys/queue.h> 4458f0484fSRodney W. Grimes #include <sys/wait.h> 4558f0484fSRodney W. Grimes 4658f0484fSRodney W. Grimes #include <signal.h> 4758f0484fSRodney W. Grimes #include <errno.h> 48e9dec775SJilles Tjoelker #include <fcntl.h> 4958f0484fSRodney W. Grimes #include <unistd.h> 5058f0484fSRodney W. Grimes #include <stdio.h> 5158f0484fSRodney W. Grimes #include <stdlib.h> 5258f0484fSRodney W. Grimes #include <string.h> 5358f0484fSRodney W. Grimes #include <paths.h> 5477e2381aSTim J. Robbins #include <pthread.h> 55d201fe46SDaniel Eischen #include "un-namespace.h" 5677e2381aSTim J. Robbins #include "libc_private.h" 5758f0484fSRodney W. Grimes 580c372549SPeter Wemm extern char **environ; 590c372549SPeter Wemm 607e7f7ca3SEd Schouten struct pid { 617e7f7ca3SEd Schouten SLIST_ENTRY(pid) next; 6258f0484fSRodney W. Grimes FILE *fp; 6358f0484fSRodney W. Grimes pid_t pid; 647e7f7ca3SEd Schouten }; 657e7f7ca3SEd Schouten static SLIST_HEAD(, pid) pidlist = SLIST_HEAD_INITIALIZER(pidlist); 6677e2381aSTim J. Robbins static pthread_mutex_t pidlist_mutex = PTHREAD_MUTEX_INITIALIZER; 6777e2381aSTim J. Robbins 6877e2381aSTim J. Robbins #define THREAD_LOCK() if (__isthreaded) _pthread_mutex_lock(&pidlist_mutex) 6977e2381aSTim J. Robbins #define THREAD_UNLOCK() if (__isthreaded) _pthread_mutex_unlock(&pidlist_mutex) 7058f0484fSRodney W. Grimes 7158f0484fSRodney W. Grimes FILE * 7255b6b759SCraig Rodrigues popen(const char *command, const char *type) 7358f0484fSRodney W. Grimes { 7458f0484fSRodney W. Grimes struct pid *cur; 7558f0484fSRodney W. Grimes FILE *iop; 76e9dec775SJilles Tjoelker int pdes[2], pid, twoway, cloexec; 773945141fSRavi Pokala int pdes_unused_in_parent; 780c372549SPeter Wemm char *argv[4]; 7926c51fb4SMike Smith struct pid *p; 8058f0484fSRodney W. Grimes 81e9dec775SJilles Tjoelker cloexec = strchr(type, 'e') != NULL; 82adf6ad9eSPeter Wemm /* 83d201fe46SDaniel Eischen * Lite2 introduced two-way popen() pipes using _socketpair(). 84adf6ad9eSPeter Wemm * FreeBSD's pipe() is bidirectional, so we use that. 85adf6ad9eSPeter Wemm */ 86adf6ad9eSPeter Wemm if (strchr(type, '+')) { 87adf6ad9eSPeter Wemm twoway = 1; 88adf6ad9eSPeter Wemm type = "r+"; 89adf6ad9eSPeter Wemm } else { 90adf6ad9eSPeter Wemm twoway = 0; 91e9dec775SJilles Tjoelker if ((*type != 'r' && *type != 'w') || 92e9dec775SJilles Tjoelker (type[1] && (type[1] != 'e' || type[2]))) 93adf6ad9eSPeter Wemm return (NULL); 94adf6ad9eSPeter Wemm } 9502804449SJilles Tjoelker if (pipe2(pdes, O_CLOEXEC) < 0) 9658f0484fSRodney W. Grimes return (NULL); 9758f0484fSRodney W. Grimes 98035e5608SBruce Evans if ((cur = malloc(sizeof(struct pid))) == NULL) { 999233c4d9SJason Evans (void)_close(pdes[0]); 1009233c4d9SJason Evans (void)_close(pdes[1]); 10158f0484fSRodney W. Grimes return (NULL); 102035e5608SBruce Evans } 10358f0484fSRodney W. Grimes 1043945141fSRavi Pokala if (*type == 'r') { 1053945141fSRavi Pokala iop = fdopen(pdes[0], type); 1063945141fSRavi Pokala pdes_unused_in_parent = pdes[1]; 1073945141fSRavi Pokala } else { 1083945141fSRavi Pokala iop = fdopen(pdes[1], type); 1093945141fSRavi Pokala pdes_unused_in_parent = pdes[0]; 1103945141fSRavi Pokala } 1113945141fSRavi Pokala if (iop == NULL) { 1123945141fSRavi Pokala (void)_close(pdes[0]); 1133945141fSRavi Pokala (void)_close(pdes[1]); 1143945141fSRavi Pokala free(cur); 1153945141fSRavi Pokala return (NULL); 1163945141fSRavi Pokala } 1173945141fSRavi Pokala 1180c372549SPeter Wemm argv[0] = "sh"; 1190c372549SPeter Wemm argv[1] = "-c"; 1200c372549SPeter Wemm argv[2] = (char *)command; 1210c372549SPeter Wemm argv[3] = NULL; 1220c372549SPeter Wemm 12377e2381aSTim J. Robbins THREAD_LOCK(); 1240c372549SPeter Wemm switch (pid = vfork()) { 12558f0484fSRodney W. Grimes case -1: /* Error. */ 12677e2381aSTim J. Robbins THREAD_UNLOCK(); 1273945141fSRavi Pokala /* 1283945141fSRavi Pokala * The _close() closes the unused end of pdes[], while 1293945141fSRavi Pokala * the fclose() closes the used end of pdes[], *and* cleans 1303945141fSRavi Pokala * up iop. 1313945141fSRavi Pokala */ 1323945141fSRavi Pokala (void)_close(pdes_unused_in_parent); 133e78bad23SJeffrey Hsu free(cur); 1343945141fSRavi Pokala (void)fclose(iop); 13558f0484fSRodney W. Grimes return (NULL); 13658f0484fSRodney W. Grimes /* NOTREACHED */ 13758f0484fSRodney W. Grimes case 0: /* Child. */ 13858f0484fSRodney W. Grimes if (*type == 'r') { 1391174d9f9SJohn Dyson /* 140d201fe46SDaniel Eischen * The _dup2() to STDIN_FILENO is repeated to avoid 1415ae9116aSJohn Dyson * writing to pdes[1], which might corrupt the 1425ae9116aSJohn Dyson * parent's copy. This isn't good enough in 1435ae9116aSJohn Dyson * general, since the _exit() is no return, so 1445ae9116aSJohn Dyson * the compiler is free to corrupt all the local 1455ae9116aSJohn Dyson * variables. 1461174d9f9SJohn Dyson */ 1475ae9116aSJohn Dyson if (pdes[1] != STDOUT_FILENO) { 148d201fe46SDaniel Eischen (void)_dup2(pdes[1], STDOUT_FILENO); 1492b9ac168SBruce Evans if (twoway) 150d201fe46SDaniel Eischen (void)_dup2(STDOUT_FILENO, STDIN_FILENO); 151e9dec775SJilles Tjoelker } else if (twoway && (pdes[1] != STDIN_FILENO)) { 152d201fe46SDaniel Eischen (void)_dup2(pdes[1], STDIN_FILENO); 153e9dec775SJilles Tjoelker (void)_fcntl(pdes[1], F_SETFD, 0); 15402804449SJilles Tjoelker } else 155e9dec775SJilles Tjoelker (void)_fcntl(pdes[1], F_SETFD, 0); 15658f0484fSRodney W. Grimes } else { 15758f0484fSRodney W. Grimes if (pdes[0] != STDIN_FILENO) { 158d201fe46SDaniel Eischen (void)_dup2(pdes[0], STDIN_FILENO); 15902804449SJilles Tjoelker } else 160e9dec775SJilles Tjoelker (void)_fcntl(pdes[0], F_SETFD, 0); 16158f0484fSRodney W. Grimes } 1627e7f7ca3SEd Schouten SLIST_FOREACH(p, &pidlist, next) 1639233c4d9SJason Evans (void)_close(fileno(p->fp)); 164d201fe46SDaniel Eischen _execve(_PATH_BSHELL, argv, environ); 16558f0484fSRodney W. Grimes _exit(127); 16658f0484fSRodney W. Grimes /* NOTREACHED */ 16758f0484fSRodney W. Grimes } 16877e2381aSTim J. Robbins THREAD_UNLOCK(); 16958f0484fSRodney W. Grimes 1703945141fSRavi Pokala /* Parent. */ 1713945141fSRavi Pokala (void)_close(pdes_unused_in_parent); 17258f0484fSRodney W. Grimes 17358f0484fSRodney W. Grimes /* Link into list of file descriptors. */ 17458f0484fSRodney W. Grimes cur->fp = iop; 17558f0484fSRodney W. Grimes cur->pid = pid; 17677e2381aSTim J. Robbins THREAD_LOCK(); 1777e7f7ca3SEd Schouten SLIST_INSERT_HEAD(&pidlist, cur, next); 17877e2381aSTim J. Robbins THREAD_UNLOCK(); 17958f0484fSRodney W. Grimes 18002804449SJilles Tjoelker /* 18102804449SJilles Tjoelker * To guard against undesired fd passing with concurrent calls, 18202804449SJilles Tjoelker * only clear the close-on-exec flag after linking the file into 18302804449SJilles Tjoelker * the list which will cause an explicit close. 18402804449SJilles Tjoelker */ 18502804449SJilles Tjoelker if (!cloexec) 18602804449SJilles Tjoelker (void)_fcntl(*type == 'r' ? pdes[0] : pdes[1], F_SETFD, 0); 18702804449SJilles Tjoelker 18858f0484fSRodney W. Grimes return (iop); 18958f0484fSRodney W. Grimes } 19058f0484fSRodney W. Grimes 19158f0484fSRodney W. Grimes /* 19258f0484fSRodney W. Grimes * pclose -- 19358f0484fSRodney W. Grimes * Pclose returns -1 if stream is not associated with a `popened' command, 19458f0484fSRodney W. Grimes * if already `pclosed', or waitpid returns an error. 19558f0484fSRodney W. Grimes */ 19658f0484fSRodney W. Grimes int 19755b6b759SCraig Rodrigues pclose(FILE *iop) 19858f0484fSRodney W. Grimes { 1997e7f7ca3SEd Schouten struct pid *cur, *last = NULL; 200adf6ad9eSPeter Wemm int pstat; 20158f0484fSRodney W. Grimes pid_t pid; 20258f0484fSRodney W. Grimes 20377e2381aSTim J. Robbins /* 20477e2381aSTim J. Robbins * Find the appropriate file pointer and remove it from the list. 20577e2381aSTim J. Robbins */ 20677e2381aSTim J. Robbins THREAD_LOCK(); 2077e7f7ca3SEd Schouten SLIST_FOREACH(cur, &pidlist, next) { 20858f0484fSRodney W. Grimes if (cur->fp == iop) 20958f0484fSRodney W. Grimes break; 2107e7f7ca3SEd Schouten last = cur; 2117e7f7ca3SEd Schouten } 21277e2381aSTim J. Robbins if (cur == NULL) { 21377e2381aSTim J. Robbins THREAD_UNLOCK(); 21458f0484fSRodney W. Grimes return (-1); 21577e2381aSTim J. Robbins } 21677e2381aSTim J. Robbins if (last == NULL) 2177e7f7ca3SEd Schouten SLIST_REMOVE_HEAD(&pidlist, next); 21877e2381aSTim J. Robbins else 2193d98b75bSEd Schouten SLIST_REMOVE_AFTER(last, next); 22077e2381aSTim J. Robbins THREAD_UNLOCK(); 22158f0484fSRodney W. Grimes 222adf6ad9eSPeter Wemm (void)fclose(iop); 223adf6ad9eSPeter Wemm 22458f0484fSRodney W. Grimes do { 2259233c4d9SJason Evans pid = _wait4(cur->pid, &pstat, 0, (struct rusage *)0); 22658f0484fSRodney W. Grimes } while (pid == -1 && errno == EINTR); 22758f0484fSRodney W. Grimes 22858f0484fSRodney W. Grimes free(cur); 22958f0484fSRodney W. Grimes 230adf6ad9eSPeter Wemm return (pid == -1 ? -1 : pstat); 23158f0484fSRodney W. Grimes } 232