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