1 /* 2 * Copyright (c) 1988 The Regents of the University of California. 3 * 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[] = "from: @(#)popen.c 5.9 (Berkeley) 2/25/91";*/ 40 static char rcsid[] = "$Id: popen.c,v 1.2 1993/08/01 18:30:43 mycroft Exp $"; 41 #endif /* not lint */ 42 43 #include <sys/types.h> 44 #include <sys/wait.h> 45 #include <signal.h> 46 #include <unistd.h> 47 #include <stdio.h> 48 #include <stdlib.h> 49 #include <string.h> 50 51 /* 52 * Special version of popen which avoids call to shell. This insures noone 53 * may create a pipe to a hidden program as a side effect of a list or dir 54 * command. 55 */ 56 static int *pids; 57 static int fds; 58 59 FILE * 60 ftpd_popen(program, type) 61 char *program, *type; 62 { 63 register char *cp; 64 FILE *iop; 65 int argc, gargc, pdes[2], pid; 66 char **pop, *argv[100], *gargv[1000], *vv[2]; 67 extern char **ftpglob(), **copyblk(); 68 69 if (*type != 'r' && *type != 'w' || type[1]) 70 return(NULL); 71 72 if (!pids) { 73 if ((fds = getdtablesize()) <= 0) 74 return(NULL); 75 if ((pids = (int *)malloc((u_int)(fds * sizeof(int)))) == NULL) 76 return(NULL); 77 bzero((char *)pids, fds * sizeof(int)); 78 } 79 if (pipe(pdes) < 0) 80 return(NULL); 81 82 /* break up string into pieces */ 83 for (argc = 0, cp = program;; cp = NULL) 84 if (!(argv[argc++] = strtok(cp, " \t\n"))) 85 break; 86 87 /* glob each piece */ 88 gargv[0] = argv[0]; 89 for (gargc = argc = 1; argv[argc]; argc++) { 90 if (!(pop = ftpglob(argv[argc]))) { /* globbing failed */ 91 vv[0] = argv[argc]; 92 vv[1] = NULL; 93 pop = copyblk(vv); 94 } 95 argv[argc] = (char *)pop; /* save to free later */ 96 while (*pop && gargc < 1000) 97 gargv[gargc++] = *pop++; 98 } 99 gargv[gargc] = NULL; 100 101 iop = NULL; 102 switch(pid = vfork()) { 103 case -1: /* error */ 104 (void)close(pdes[0]); 105 (void)close(pdes[1]); 106 goto pfree; 107 /* NOTREACHED */ 108 case 0: /* child */ 109 if (*type == 'r') { 110 if (pdes[1] != 1) { 111 dup2(pdes[1], 1); 112 dup2(pdes[1], 2); /* stderr, too! */ 113 (void)close(pdes[1]); 114 } 115 (void)close(pdes[0]); 116 } else { 117 if (pdes[0] != 0) { 118 dup2(pdes[0], 0); 119 (void)close(pdes[0]); 120 } 121 (void)close(pdes[1]); 122 } 123 execv(gargv[0], gargv); 124 _exit(1); 125 } 126 /* parent; assume fdopen can't fail... */ 127 if (*type == 'r') { 128 iop = fdopen(pdes[0], type); 129 (void)close(pdes[1]); 130 } else { 131 iop = fdopen(pdes[1], type); 132 (void)close(pdes[0]); 133 } 134 pids[fileno(iop)] = pid; 135 136 pfree: for (argc = 1; argv[argc] != NULL; argc++) { 137 blkfree((char **)argv[argc]); 138 free((char *)argv[argc]); 139 } 140 return(iop); 141 } 142 143 ftpd_pclose(iop) 144 FILE *iop; 145 { 146 register int fdes; 147 int omask; 148 union wait stat_loc; 149 int pid; 150 151 /* 152 * pclose returns -1 if stream is not associated with a 153 * `popened' command, or, if already `pclosed'. 154 */ 155 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 156 return(-1); 157 (void)fclose(iop); 158 omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP)); 159 while ((pid = wait((int *)&stat_loc)) != pids[fdes] && pid != -1); 160 (void)sigsetmask(omask); 161 pids[fdes] = 0; 162 return(pid == -1 ? -1 : stat_loc.w_status); 163 } 164