contrib/opie/popen.c

   1 /* popen.c: A "safe" pipe open routine.
   2
   3 %%% portions-copyright-cmetz-96
   4 Portions of this software are Copyright 1996-1999 by Craig Metz, All Rights
   5 Reserved. The Inner Net License Version 2 applies to these portions of
   6 the software.
   7 You should have received a copy of the license with this software. If
   8 you didn't get a copy, you may request one from <license@inner.net>.
   9
  10 Portions of this software are Copyright 1995 by Randall Atkinson and Dan
  11 McDonald, All Rights Reserved. All Rights under this copyright are assigned
  12 to the U.S. Naval Research Laboratory (NRL). The NRL Copyright Notice and
  13 License Agreement applies to this software.
  14
  15         History:
  16
  17         Modified by cmetz for OPIE 2.31. Merged in some 4.4BSD-Lite fixes.
  18         Modified by cmetz for OPIE 2.2. Use FUNCTION declaration et al.
  19                 Removed useless string. ifdef around some headers.
  20         Modified at NRL for OPIE 2.1. Optimized for only one pipe at a time.
  21                 Added minimal version of sigprocmask(). Moved some pid_t
  22                 dancing to the config headers.
  23         Modified at NRL for OPIE 2.0.
  24         Originally from BSD.
  25
  26 */
  27 /*
  28  * Copyright (c) 1988, 1993, 1994
  29  *     The Regents of the University of California.  All rights reserved.
  30  *
  31  * This code is derived from software written by Ken Arnold and
  32  * published in UNIX Review, Vol. 6, No. 8.
  33  *
  34  * Redistribution and use in source and binary forms, with or without
  35  * modification, are permitted provided that the following conditions
  36  * are met:
  37  * 1. Redistributions of source code must retain the above copyright
  38  *    notice, this list of conditions and the following disclaimer.
  39  * 2. Redistributions in binary form must reproduce the above copyright
  40  *    notice, this list of conditions and the following disclaimer in the
  41  *    documentation and/or other materials provided with the distribution.
  42  * 3. All advertising materials mentioning features or use of this software
  43  *    must display the following acknowledgement:
  44  *      This product includes software developed by the University of
  45  *      California, Berkeley and its contributors.
  46  * 4. Neither the name of the University nor the names of its contributors
  47  *    may be used to endorse or promote products derived from this software
  48  *    without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  53  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  60  * SUCH DAMAGE.
  61  *
  62  */
  63
  64 #include "opie_cfg.h"
  65
  66 #include <sys/types.h>
  67 #include <sys/wait.h>
  68 #if HAVE_SIGNAL_H
  69 #include <signal.h>
  70 #endif /* HAVE_SIGNAL_H */
  71 #if HAVE_SYS_SIGNAL_H
  72 #include <sys/signal.h>
  73 #endif /* HAVE_SYS_SIGNAL_H */
  74 #if HAVE_UNISTD_H
  75 #include <unistd.h>
  76 #endif /* HAVE_UNISTD_H */
  77 #include <stdio.h>
  78 #if HAVE_STDLIB_H
  79 #include <stdlib.h>
  80 #endif /* HAVE_STDLIB_H */
  81 #if HAVE_STRING_H
  82 #include <string.h>
  83 #endif /* HAVE_STRING_H */
  84
  85 #include "opie.h"
  86
  87 char **ftpglob __P((register char *));
  88 char **copyblk __P((char **));
  89 VOIDRET blkfree __P((char **));
  90
  91 /*
  92  * Special version of popen which avoids call to shell.  This ensures noone
  93  * may create a pipe to a hidden program as a side effect of a list or dir
  94  * command.
  95  */
  96 static pid_t child_pid = -1;
  97 static int pipe_fd;
  98
  99 extern char **environ;
 100
 101 FILE *ftpd_popen FUNCTION((program, type), char *program AND char *type)
 102 {
 103   char *cp;
 104   FILE *iop;
 105   int argc, gargc, pdes[2];
 106   char **pop, *argv[100], *gargv[1000], *vv[2];
 107
 108   if ((*type != 'r' && *type != 'w') || type[1])
 109     return (NULL);
 110
 111   if (pipe(pdes) < 0)
 112     return (NULL);
 113
 114   /* break up string into pieces */
 115   for (argc = 0, cp = program;; cp = NULL)
 116     if (!(argv[argc++] = strtok(cp, " \t\n")))
 117       break;
 118
 119   /* glob each piece */
 120   gargv[0] = argv[0];
 121   for (gargc = argc = 1; argv[argc]; argc++) {
 122     if (!(pop = (char **) ftpglob(argv[argc]))) {
 123       /* globbing failed */
 124       vv[0] = argv[argc];
 125       vv[1] = NULL;
 126       pop = (char **) copyblk(vv);
 127     }
 128     argv[argc] = (char *) pop;  /* save to free later */
 129     while (*pop && gargc < 1000)
 130       gargv[gargc++] = *pop++;
 131   }
 132   gargv[gargc] = NULL;
 133
 134   iop = NULL;
 135   switch (child_pid = fork()) {
 136   case -1:      /* error */
 137     close(pdes[0]);
 138     close(pdes[1]);
 139     goto pfree;
 140     /* NOTREACHED */
 141   case 0:       /* child */
 142     if (*type == 'r') {
 143       if (pdes[1] != 1) {
 144         dup2(pdes[1], 1);
 145         dup2(pdes[1], 2);       /* stderr, too! */
 146         close(pdes[1]);
 147       }
 148       close(pdes[0]);
 149     } else {
 150       if (pdes[0] != 0) {
 151         dup2(pdes[0], 0);
 152         close(pdes[0]);
 153       }
 154       close(pdes[1]);
 155     }
 156     environ = NULL;
 157     execv(gargv[0], gargv);
 158     _exit(1);
 159   }
 160
 161   /* parent; assume fdopen can't fail...  */
 162   if (*type == 'r') {
 163     iop = fdopen(pipe_fd = pdes[0], type);
 164     close(pdes[1]);
 165   } else {
 166     iop = fdopen(pipe_fd = pdes[1], type);
 167     close(pdes[0]);
 168   }
 169
 170 pfree: for (argc = 1; argv[argc] != NULL; argc++) {
 171     blkfree((char **) argv[argc]);
 172     free((char *) argv[argc]);
 173   }
 174   return (iop);
 175 }
 176
 177 int ftpd_pclose FUNCTION((iop), FILE *iop)
 178 {
 179   int status;
 180   pid_t pid;
 181   sigset_t omask, mask;
 182
 183   sigemptyset(&mask);
 184   sigaddset(&mask, SIGINT);
 185   sigaddset(&mask, SIGQUIT);
 186   sigaddset(&mask, SIGHUP);
 187
 188   /* pclose returns -1 if stream is not associated with a `popened' command,
 189      or, if already `pclosed'. */
 190   if ((child_pid < 0) || (fileno(iop) != pipe_fd))
 191     return (-1);
 192
 193   fclose(iop);
 194   sigprocmask(SIG_BLOCK, &mask, &omask);
 195
 196   while ((pid = wait(&status)) != child_pid && (pid != -1));
 197   sigprocmask(SIG_SETMASK, &omask, NULL);
 198
 199   child_pid = -1;
 200   pipe_fd = -1;
 201
 202 #if defined(WEXITSTATUS) && defined(WIFEXITED)
 203   if ((pid > 0) && WIFEXITED(status))
 204     return WEXITSTATUS(status);
 205
 206   return -1;
 207 #else /* defined(WEXITSTATUS) && defined(WIFEXITED) */
 208   return (pid == -1 ? -1 : status.w_status);
 209 #endif /* defined(WEXITSTATUS) && defined(WIFEXITED) */
 210 }