ftpd.tproj/popen.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * "Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.0 (the 'License').  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License."
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*
  25  * Copyright (c) 1988, 1993, 1994
  26  *      The Regents of the University of California.  All rights reserved.
  27  *
  28  * This code is derived from software written by Ken Arnold and
  29  * published in UNIX Review, Vol. 6, No. 8.
  30  *
  31  * Redistribution and use in source and binary forms, with or without
  32  * modification, are permitted provided that the following conditions
  33  * are met:
  34  * 1. Redistributions of source code must retain the above copyright
  35  *    notice, this list of conditions and the following disclaimer.
  36  * 2. Redistributions in binary form must reproduce the above copyright
  37  *    notice, this list of conditions and the following disclaimer in the
  38  *    documentation and/or other materials provided with the distribution.
  39  * 3. All advertising materials mentioning features or use of this software
  40  *    must display the following acknowledgement:
  41  *      This product includes software developed by the University of
  42  *      California, Berkeley and its contributors.
  43  * 4. Neither the name of the University nor the names of its contributors
  44  *    may be used to endorse or promote products derived from this software
  45  *    without specific prior written permission.
  46  *
  47  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  48  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  49  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  50  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  51  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  52  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  53  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  54  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  55  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  56  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  57  * SUCH DAMAGE.
  58  *
  59  */
  60
  61 #ifndef lint
  62 static char sccsid[] = "@(#)popen.c     8.3 (Berkeley) 4/6/94";
  63 #endif /* not lint */
  64
  65 #include <sys/types.h>
  66 #include <sys/wait.h>
  67
  68 #include <errno.h>
  69 #include <glob.h>
  70 #include <signal.h>
  71 #include <stdio.h>
  72 #include <stdlib.h>
  73 #include <string.h>
  74 #include <unistd.h>
  75
  76 #include "extern.h"
  77
  78 /*
  79  * Special version of popen which avoids call to shell.  This ensures noone
  80  * may create a pipe to a hidden program as a side effect of a list or dir
  81  * command.
  82  */
  83 static int *pids;
  84 static int fds;
  85
  86 FILE *
  87 ftpd_popen(program, type)
  88         char *program, *type;
  89 {
  90         char *cp;
  91         FILE *iop;
  92         int argc, gargc, pdes[2], pid;
  93         char **pop, *argv[100], *gargv[1000];
  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         /* break up string into pieces */
 109         for (argc = 0, cp = program;; cp = NULL)
 110                 if (!(argv[argc++] = strtok(cp, " \t\n")))
 111                         break;
 112
 113         /* glob each piece */
 114         gargv[0] = argv[0];
 115         for (gargc = argc = 1; argv[argc]; argc++) {
 116                 glob_t gl;
 117                 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE;
 118
 119                 memset(&gl, 0, sizeof(gl));
 120                 if (glob(argv[argc], flags, NULL, &gl))
 121                         gargv[gargc++] = strdup(argv[argc]);
 122                 else
 123                         for (pop = gl.gl_pathv; *pop; pop++)
 124                                 gargv[gargc++] = strdup(*pop);
 125                 globfree(&gl);
 126         }
 127         gargv[gargc] = NULL;
 128
 129         iop = NULL;
 130         switch(pid = vfork()) {
 131         case -1:                        /* error */
 132                 (void)close(pdes[0]);
 133                 (void)close(pdes[1]);
 134                 goto pfree;
 135                 /* NOTREACHED */
 136         case 0:                         /* child */
 137                 if (*type == 'r') {
 138                         if (pdes[1] != STDOUT_FILENO) {
 139                                 dup2(pdes[1], STDOUT_FILENO);
 140                                 (void)close(pdes[1]);
 141                         }
 142                         dup2(STDOUT_FILENO, STDERR_FILENO); /* stderr too! */
 143                         (void)close(pdes[0]);
 144                 } else {
 145                         if (pdes[0] != STDIN_FILENO) {
 146                                 dup2(pdes[0], STDIN_FILENO);
 147                                 (void)close(pdes[0]);
 148                         }
 149                         (void)close(pdes[1]);
 150                 }
 151                 execv(gargv[0], gargv);
 152                 _exit(1);
 153         }
 154         /* parent; assume fdopen can't fail...  */
 155         if (*type == 'r') {
 156                 iop = fdopen(pdes[0], type);
 157                 (void)close(pdes[1]);
 158         } else {
 159                 iop = fdopen(pdes[1], type);
 160                 (void)close(pdes[0]);
 161         }
 162         pids[fileno(iop)] = pid;
 163
 164 pfree:  for (argc = 1; gargv[argc] != NULL; argc++)
 165                 free(gargv[argc]);
 166
 167         return (iop);
 168 }
 169
 170 int
 171 ftpd_pclose(iop)
 172         FILE *iop;
 173 {
 174         int fdes, omask, status;
 175         pid_t pid;
 176
 177         /*
 178          * pclose returns -1 if stream is not associated with a
 179          * `popened' command, or, if already `pclosed'.
 180          */
 181         if (pids == 0 || pids[fdes = fileno(iop)] == 0)
 182                 return (-1);
 183         (void)fclose(iop);
 184         omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP));
 185         while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR)
 186                 continue;
 187         (void)sigsetmask(omask);
 188         pids[fdes] = 0;
 189         if (pid < 0)
 190                 return (pid);
 191         if (WIFEXITED(status))
 192                 return (WEXITSTATUS(status));
 193         return (1);
 194 }