1 /* $NetBSD: popen.c,v 1.13 1999/02/24 16:45:13 explorer 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 1.13 1999/02/24 16:45:13 explorer 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 #ifdef KERBEROS5 61 #include <krb5.h> 62 #endif 63 64 #include "extern.h" 65 66 #define INCR 100 67 /* 68 * Special version of popen which avoids call to shell. This ensures no-one 69 * may create a pipe to a hidden program as a side effect of a list or dir 70 * command. 71 * If stderrfd != -1, then send stderr of a read command there, 72 * otherwise close stderr. 73 */ 74 static int *pids; 75 static int fds; 76 77 FILE * 78 ftpd_popen(program, type, stderrfd) 79 char *program, *type; 80 int stderrfd; 81 { 82 char *cp; 83 FILE *iop = NULL; 84 int argc, gargc, pdes[2], pid; 85 char **pop, **np; 86 char **argv = NULL, **gargv = NULL; 87 size_t nargc = 100, ngargc = 100; 88 #ifdef __GNUC__ 89 (void) &iop; 90 (void) &gargc; 91 (void) &gargv; 92 (void) &argv; 93 #endif 94 95 if ((*type != 'r' && *type != 'w') || type[1]) 96 return (NULL); 97 98 if (!pids) { 99 if ((fds = getdtablesize()) <= 0) 100 return (NULL); 101 if ((pids = (int *)malloc((u_int)(fds * sizeof(int)))) == NULL) 102 return (NULL); 103 memset(pids, 0, fds * sizeof(int)); 104 } 105 if (pipe(pdes) < 0) 106 return (NULL); 107 108 if ((argv = malloc(nargc * sizeof(char *))) == NULL) 109 return NULL; 110 111 #define CHECKMORE(c, v, n) \ 112 if (c >= n + 2) { \ 113 n += INCR; \ 114 if ((np = realloc(v, n * sizeof(char *))) == NULL) \ 115 goto pfree; \ 116 else \ 117 v = np; \ 118 } 119 120 /* break up string into pieces */ 121 for (argc = 0, cp = program;; cp = NULL) { 122 CHECKMORE(argc, argv, nargc) 123 if (!(argv[argc++] = strtok(cp, " \t\n"))) 124 break; 125 } 126 127 if ((gargv = malloc(ngargc * sizeof(char *))) == NULL) 128 goto pfree; 129 130 /* glob each piece */ 131 gargv[0] = argv[0]; 132 for (gargc = argc = 1; argv[argc]; argc++) { 133 glob_t gl; 134 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE; 135 136 memset(&gl, 0, sizeof(gl)); 137 if (glob(argv[argc], flags, NULL, &gl)) { 138 CHECKMORE(gargc, gargv, ngargc) 139 if ((gargv[gargc++] = strdup(argv[argc])) == NULL) 140 goto pfree; 141 } 142 else 143 for (pop = gl.gl_pathv; *pop; pop++) { 144 CHECKMORE(gargc, gargv, ngargc) 145 if ((gargv[gargc++] = strdup(*pop)) == NULL) 146 goto pfree; 147 } 148 globfree(&gl); 149 } 150 gargv[gargc] = NULL; 151 152 switch(pid = vfork()) { 153 case -1: /* error */ 154 (void)close(pdes[0]); 155 (void)close(pdes[1]); 156 goto pfree; 157 /* NOTREACHED */ 158 case 0: /* child */ 159 if (*type == 'r') { 160 if (pdes[1] != STDOUT_FILENO) { 161 dup2(pdes[1], STDOUT_FILENO); 162 (void)close(pdes[1]); 163 } 164 if (stderrfd == -1) 165 (void)close(STDERR_FILENO); 166 else 167 dup2(stderrfd, STDERR_FILENO); 168 (void)close(pdes[0]); 169 } else { 170 if (pdes[0] != STDIN_FILENO) { 171 dup2(pdes[0], STDIN_FILENO); 172 (void)close(pdes[0]); 173 } 174 (void)close(pdes[1]); 175 } 176 execv(gargv[0], gargv); 177 _exit(1); 178 } 179 /* parent; assume fdopen can't fail... */ 180 if (*type == 'r') { 181 iop = fdopen(pdes[0], type); 182 (void)close(pdes[1]); 183 } else { 184 iop = fdopen(pdes[1], type); 185 (void)close(pdes[0]); 186 } 187 pids[fileno(iop)] = pid; 188 189 pfree: if (gargv) { 190 for (argc = 1; argc < gargc; argc++) 191 free(gargv[argc]); 192 free(gargv); 193 } 194 if (argv) 195 free(argv); 196 197 return (iop); 198 } 199 200 int 201 ftpd_pclose(iop) 202 FILE *iop; 203 { 204 int fdes, status; 205 pid_t pid; 206 sigset_t sigset, osigset; 207 208 /* 209 * pclose returns -1 if stream is not associated with a 210 * `popened' command, or, if already `pclosed'. 211 */ 212 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 213 return (-1); 214 (void)fclose(iop); 215 sigemptyset(&sigset); 216 sigaddset(&sigset, SIGINT); 217 sigaddset(&sigset, SIGQUIT); 218 sigaddset(&sigset, SIGHUP); 219 sigprocmask(SIG_BLOCK, &sigset, &osigset); 220 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR) 221 continue; 222 sigprocmask(SIG_SETMASK, &osigset, NULL); 223 pids[fdes] = 0; 224 if (pid < 0) 225 return (pid); 226 if (WIFEXITED(status)) 227 return (WEXITSTATUS(status)); 228 return (1); 229 } 230