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 */ 37 38 #ifndef lint 39 static char sccsid[] = "@(#)popen.c 8.3 (Berkeley) 4/6/94"; 40 #endif /* not lint */ 41 42 #include <sys/types.h> 43 #include <sys/wait.h> 44 45 #include <errno.h> 46 #include <glob.h> 47 #include <signal.h> 48 #include <stdio.h> 49 #include <stdlib.h> 50 #include <string.h> 51 #include <unistd.h> 52 53 #include "extern.h" 54 55 /* 56 * Special version of popen which avoids call to shell. This ensures noone 57 * may create a pipe to a hidden program as a side effect of a list or dir 58 * command. 59 */ 60 static int *pids; 61 static int fds; 62 63 FILE * 64 ftpd_popen(program, type) 65 char *program, *type; 66 { 67 char *cp; 68 FILE *iop; 69 int argc, gargc, pdes[2], pid; 70 char **pop, *argv[100], *gargv[1000]; 71 72 if (*type != 'r' && *type != 'w' || type[1]) 73 return (NULL); 74 75 if (!pids) { 76 if ((fds = getdtablesize()) <= 0) 77 return (NULL); 78 if ((pids = (int *)malloc((u_int)(fds * sizeof(int)))) == NULL) 79 return (NULL); 80 memset(pids, 0, fds * sizeof(int)); 81 } 82 if (pipe(pdes) < 0) 83 return (NULL); 84 85 /* break up string into pieces */ 86 for (argc = 0, cp = program;; cp = NULL) 87 if (!(argv[argc++] = strtok(cp, " \t\n"))) 88 break; 89 90 /* glob each piece */ 91 gargv[0] = argv[0]; 92 for (gargc = argc = 1; argv[argc]; argc++) { 93 glob_t gl; 94 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE; 95 96 memset(&gl, 0, sizeof(gl)); 97 if (glob(argv[argc], flags, NULL, &gl)) 98 gargv[gargc++] = strdup(argv[argc]); 99 else 100 for (pop = gl.gl_pathv; *pop; pop++) 101 gargv[gargc++] = strdup(*pop); 102 globfree(&gl); 103 } 104 gargv[gargc] = NULL; 105 106 iop = NULL; 107 switch(pid = vfork()) { 108 case -1: /* error */ 109 (void)close(pdes[0]); 110 (void)close(pdes[1]); 111 goto pfree; 112 /* NOTREACHED */ 113 case 0: /* child */ 114 if (*type == 'r') { 115 if (pdes[1] != STDOUT_FILENO) { 116 dup2(pdes[1], STDOUT_FILENO); 117 (void)close(pdes[1]); 118 } 119 dup2(STDOUT_FILENO, STDERR_FILENO); /* stderr too! */ 120 (void)close(pdes[0]); 121 } else { 122 if (pdes[0] != STDIN_FILENO) { 123 dup2(pdes[0], STDIN_FILENO); 124 (void)close(pdes[0]); 125 } 126 (void)close(pdes[1]); 127 } 128 execv(gargv[0], gargv); 129 _exit(1); 130 } 131 /* parent; assume fdopen can't fail... */ 132 if (*type == 'r') { 133 iop = fdopen(pdes[0], type); 134 (void)close(pdes[1]); 135 } else { 136 iop = fdopen(pdes[1], type); 137 (void)close(pdes[0]); 138 } 139 pids[fileno(iop)] = pid; 140 141 pfree: for (argc = 1; gargv[argc] != NULL; argc++) 142 free(gargv[argc]); 143 144 return (iop); 145 } 146 147 int 148 ftpd_pclose(iop) 149 FILE *iop; 150 { 151 int fdes, omask, status; 152 pid_t pid; 153 154 /* 155 * pclose returns -1 if stream is not associated with a 156 * `popened' command, or, if already `pclosed'. 157 */ 158 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 159 return (-1); 160 (void)fclose(iop); 161 omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP)); 162 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR) 163 continue; 164 (void)sigsetmask(omask); 165 pids[fdes] = 0; 166 if (pid < 0) 167 return (pid); 168 if (WIFEXITED(status)) 169 return (WEXITSTATUS(status)); 170 return (1); 171 } 172