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