1 /* $NetBSD: popen.c,v 1.12 1998/12/28 04:54:01 lukem Exp $ */ 2 3 /* 4 * Copyright (c) 1988, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software written by Ken Arnold and 8 * published in UNIX Review, Vol. 6, No. 8. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 */ 39 40 #include <sys/cdefs.h> 41 #ifndef lint 42 #if 0 43 static char sccsid[] = "@(#)popen.c 8.3 (Berkeley) 4/6/94"; 44 #else 45 __RCSID("$NetBSD: popen.c,v 1.12 1998/12/28 04:54:01 lukem 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 <unistd.h> 59 60 #include "extern.h" 61 62 #define INCR 100 63 /* 64 * Special version of popen which avoids call to shell. This ensures no-one 65 * may create a pipe to a hidden program as a side effect of a list or dir 66 * command. 67 * If stderrfd != -1, then send stderr of a read command there, 68 * otherwise close stderr. 69 */ 70 static int *pids; 71 static int fds; 72 73 FILE * 74 ftpd_popen(program, type, stderrfd) 75 char *program, *type; 76 int stderrfd; 77 { 78 char *cp; 79 FILE *iop = NULL; 80 int argc, gargc, pdes[2], pid; 81 char **pop, **np; 82 char **argv = NULL, **gargv = NULL; 83 size_t nargc = 100, ngargc = 100; 84 #ifdef __GNUC__ 85 (void) &iop; 86 (void) &gargc; 87 (void) &gargv; 88 (void) &argv; 89 #endif 90 91 if ((*type != 'r' && *type != 'w') || type[1]) 92 return (NULL); 93 94 if (!pids) { 95 if ((fds = getdtablesize()) <= 0) 96 return (NULL); 97 if ((pids = (int *)malloc((u_int)(fds * sizeof(int)))) == NULL) 98 return (NULL); 99 memset(pids, 0, fds * sizeof(int)); 100 } 101 if (pipe(pdes) < 0) 102 return (NULL); 103 104 if ((argv = malloc(nargc * sizeof(char *))) == NULL) 105 return NULL; 106 107 #define CHECKMORE(c, v, n) \ 108 if (c >= n + 2) { \ 109 n += INCR; \ 110 if ((np = realloc(v, n * sizeof(char *))) == NULL) \ 111 goto pfree; \ 112 else \ 113 v = np; \ 114 } 115 116 /* break up string into pieces */ 117 for (argc = 0, cp = program;; cp = NULL) { 118 CHECKMORE(argc, argv, nargc) 119 if (!(argv[argc++] = strtok(cp, " \t\n"))) 120 break; 121 } 122 123 if ((gargv = malloc(ngargc * sizeof(char *))) == NULL) 124 goto pfree; 125 126 /* glob each piece */ 127 gargv[0] = argv[0]; 128 for (gargc = argc = 1; argv[argc]; argc++) { 129 glob_t gl; 130 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE; 131 132 memset(&gl, 0, sizeof(gl)); 133 if (glob(argv[argc], flags, NULL, &gl)) { 134 CHECKMORE(gargc, gargv, ngargc) 135 if ((gargv[gargc++] = strdup(argv[argc])) == NULL) 136 goto pfree; 137 } 138 else 139 for (pop = gl.gl_pathv; *pop; pop++) { 140 CHECKMORE(gargc, gargv, ngargc) 141 if ((gargv[gargc++] = strdup(*pop)) == NULL) 142 goto pfree; 143 } 144 globfree(&gl); 145 } 146 gargv[gargc] = NULL; 147 148 switch(pid = vfork()) { 149 case -1: /* error */ 150 (void)close(pdes[0]); 151 (void)close(pdes[1]); 152 goto pfree; 153 /* NOTREACHED */ 154 case 0: /* child */ 155 if (*type == 'r') { 156 if (pdes[1] != STDOUT_FILENO) { 157 dup2(pdes[1], STDOUT_FILENO); 158 (void)close(pdes[1]); 159 } 160 if (stderrfd == -1) 161 (void)close(STDERR_FILENO); 162 else 163 dup2(stderrfd, STDERR_FILENO); 164 (void)close(pdes[0]); 165 } else { 166 if (pdes[0] != STDIN_FILENO) { 167 dup2(pdes[0], STDIN_FILENO); 168 (void)close(pdes[0]); 169 } 170 (void)close(pdes[1]); 171 } 172 execv(gargv[0], gargv); 173 _exit(1); 174 } 175 /* parent; assume fdopen can't fail... */ 176 if (*type == 'r') { 177 iop = fdopen(pdes[0], type); 178 (void)close(pdes[1]); 179 } else { 180 iop = fdopen(pdes[1], type); 181 (void)close(pdes[0]); 182 } 183 pids[fileno(iop)] = pid; 184 185 pfree: if (gargv) { 186 for (argc = 1; argc < gargc; argc++) 187 free(gargv[argc]); 188 free(gargv); 189 } 190 if (argv) 191 free(argv); 192 193 return (iop); 194 } 195 196 int 197 ftpd_pclose(iop) 198 FILE *iop; 199 { 200 int fdes, status; 201 pid_t pid; 202 sigset_t sigset, osigset; 203 204 /* 205 * pclose returns -1 if stream is not associated with a 206 * `popened' command, or, if already `pclosed'. 207 */ 208 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 209 return (-1); 210 (void)fclose(iop); 211 sigemptyset(&sigset); 212 sigaddset(&sigset, SIGINT); 213 sigaddset(&sigset, SIGQUIT); 214 sigaddset(&sigset, SIGHUP); 215 sigprocmask(SIG_BLOCK, &sigset, &osigset); 216 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR) 217 continue; 218 sigprocmask(SIG_SETMASK, &osigset, NULL); 219 pids[fdes] = 0; 220 if (pid < 0) 221 return (pid); 222 if (WIFEXITED(status)) 223 return (WEXITSTATUS(status)); 224 return (1); 225 } 226