popen.c revision 1.11
1/* $OpenBSD: popen.c,v 1.11 1999/12/08 13:15:21 itojun Exp $ */ 2/* $NetBSD: popen.c,v 1.5 1995/04/11 02:45:00 cgd Exp $ */ 3 4/* 5 * Copyright (c) 1988, 1993, 1994 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software written by Ken Arnold and 9 * published in UNIX Review, Vol. 6, No. 8. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 */ 40 41#ifndef lint 42#if 0 43static char sccsid[] = "@(#)popen.c 8.3 (Berkeley) 4/6/94"; 44#else 45static char rcsid[] = "$NetBSD: popen.c,v 1.5 1995/04/11 02:45:00 cgd Exp $"; 46#endif 47#endif /* not lint */ 48 49#include <sys/types.h> 50#include <sys/wait.h> 51 52#include <errno.h> 53#include <glob.h> 54#include <signal.h> 55#include <stdio.h> 56#include <stdlib.h> 57#include <string.h> 58#include <syslog.h> 59#include <unistd.h> 60 61#include <netinet/in.h> 62#include "extern.h" 63 64/* 65 * Special version of popen which avoids call to shell. This ensures noone 66 * may create a pipe to a hidden program as a side effect of a list or dir 67 * command. 68 */ 69static int *pids; 70static int fds; 71 72#define MAX_ARGV 100 73#define MAX_GARGV 1000 74 75FILE * 76ftpd_popen(program, type) 77 char *program, *type; 78{ 79 char *cp; 80 FILE *iop; 81 int argc, gargc, pdes[2], pid; 82 char **pop, *argv[MAX_ARGV], *gargv[MAX_GARGV]; 83 84 if ((*type != 'r' && *type != 'w') || type[1]) 85 return (NULL); 86 87 if (!pids) { 88 if ((fds = getdtablesize()) <= 0) 89 return (NULL); 90 if ((pids = (int *)malloc((u_int)(fds * sizeof(int)))) == NULL) 91 return (NULL); 92 memset(pids, 0, fds * sizeof(int)); 93 } 94 if (pipe(pdes) < 0) 95 return (NULL); 96 97 /* break up string into pieces */ 98 for (argc = 0, cp = program;argc < MAX_ARGV-1; cp = NULL) 99 if (!(argv[argc++] = strtok(cp, " \t\n"))) 100 break; 101 argv[MAX_ARGV-1] = NULL; 102 103 /* glob each piece */ 104 gargv[0] = argv[0]; 105 for (gargc = argc = 1; argv[argc]; argc++) { 106 glob_t gl; 107 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE; 108 109 memset(&gl, 0, sizeof(gl)); 110 if (glob(argv[argc], flags, NULL, &gl)) { 111 if (gargc < MAX_GARGV-1) { 112 gargv[gargc++] = strdup(argv[argc]); 113 if (gargv[gargc -1] == NULL) 114 fatal ("Out of memory"); 115 } 116 117 } else 118 for (pop = gl.gl_pathv; *pop && gargc < MAX_GARGV-1; pop++) { 119 gargv[gargc++] = strdup(*pop); 120 if (gargv[gargc - 1] == NULL) 121 fatal ("Out of memory"); 122 } 123 globfree(&gl); 124 } 125 gargv[gargc] = NULL; 126 127 iop = NULL; 128 129 switch(pid = fork()) { 130 case -1: /* error */ 131 (void)close(pdes[0]); 132 (void)close(pdes[1]); 133 goto pfree; 134 /* NOTREACHED */ 135 case 0: /* child */ 136 if (*type == 'r') { 137 if (pdes[1] != STDOUT_FILENO) { 138 dup2(pdes[1], STDOUT_FILENO); 139 (void)close(pdes[1]); 140 } 141 dup2(STDOUT_FILENO, STDERR_FILENO); /* stderr too! */ 142 (void)close(pdes[0]); 143 } else { 144 if (pdes[0] != STDIN_FILENO) { 145 dup2(pdes[0], STDIN_FILENO); 146 (void)close(pdes[0]); 147 } 148 (void)close(pdes[1]); 149 } 150 closelog(); 151 152 if (strcmp(gargv[0], "/bin/ls") == 0) { 153 extern int optreset; 154 /* reset getopt for ls_main */ 155 optreset = optind = 1; 156 exit(ls_main(gargc, gargv)); 157 } 158 159 execv(gargv[0], gargv); 160 _exit(1); 161 } 162 /* parent; assume fdopen can't fail... */ 163 if (*type == 'r') { 164 iop = fdopen(pdes[0], type); 165 (void)close(pdes[1]); 166 } else { 167 iop = fdopen(pdes[1], type); 168 (void)close(pdes[0]); 169 } 170 pids[fileno(iop)] = pid; 171 172pfree: for (argc = 1; gargv[argc] != NULL; argc++) 173 free(gargv[argc]); 174 175 return (iop); 176} 177 178int 179ftpd_pclose(iop) 180 FILE *iop; 181{ 182 int fdes, status; 183 pid_t pid; 184 sigset_t sigset, osigset; 185 186 /* 187 * pclose returns -1 if stream is not associated with a 188 * `popened' command, or, if already `pclosed'. 189 */ 190 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 191 return (-1); 192 (void)fclose(iop); 193 sigemptyset(&sigset); 194 sigaddset(&sigset, SIGINT); 195 sigaddset(&sigset, SIGQUIT); 196 sigaddset(&sigset, SIGHUP); 197 sigprocmask(SIG_BLOCK, &sigset, &osigset); 198 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR) 199 continue; 200 sigprocmask(SIG_SETMASK, &osigset, NULL); 201 pids[fdes] = 0; 202 if (pid < 0) 203 return (pid); 204 if (WIFEXITED(status)) 205 return (WEXITSTATUS(status)); 206 return (1); 207} 208