eliminate local version of glob (cf ftp)

[unix-history] / usr / src / libexec / ftpd / popen.c

/*
* Copyright (c) 1988, 1993, 1994
*      The Regents of the University of California.  All rights reserved.
*
* This code is derived from software written by Ken Arnold and
* published in UNIX Review, Vol. 6, No. 8.
*
* %sccs.include.redist.c%
*
*/

#ifndef lint
static char sccsid[] = "@(#)popen.c     8.2 (Berkeley) %G%";
#endif /* not lint */

#include <sys/types.h>
#include <sys/wait.h>

#include <errno.h>
#include <glob.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "extern.h"

/*
* Special version of popen which avoids call to shell.  This ensures noone
* may create a pipe to a hidden program as a side effect of a list or dir
* command.
*/
static int *pids;
static int fds;

FILE *
ftpd_popen(program, type)
       char *program, *type;
{
       char *cp;
       FILE *iop;
       int argc, gargc, pdes[2], pid;
       char **pop, *argv[100], *gargv[1000];

       if (*type != 'r' && *type != 'w' || type[1])
               return (NULL);

       if (!pids) {
               if ((fds = getdtablesize()) <= 0)
                       return (NULL);
               if ((pids = (int *)malloc((u_int)(fds * sizeof(int)))) == NULL)
                       return (NULL);
               memset(pids, 0, fds * sizeof(int));
       }
       if (pipe(pdes) < 0)
               return (NULL);

       /* break up string into pieces */
       for (argc = 0, cp = program;; cp = NULL)
               if (!(argv[argc++] = strtok(cp, " \t\n")))
                       break;

       /* glob each piece */
       gargv[0] = argv[0];
       for (gargc = argc = 1; argv[argc]; argc++) {
               glob_t gl;
               int flags = GLOB_BRACE|GLOB_QUOTE|GLOB_TILDE;

               memset(&gl, 0, sizeof(gl));
               if (glob(argv[argc], flags, NULL, &gl))
                       gargv[gargc++] = strdup(argv[argc]);
               else
                       for (pop = gl.gl_pathv; *pop; pop++)
                               gargv[gargc++] = strdup(*pop);
               globfree(&gl);
       }
       gargv[gargc] = NULL;

       iop = NULL;
       switch(pid = vfork()) {
       case -1:                        /* error */
               (void)close(pdes[0]);
               (void)close(pdes[1]);
               goto pfree;
               /* NOTREACHED */
       case 0:                         /* child */
               if (*type == 'r') {
                       if (pdes[1] != STDOUT_FILENO) {
                               dup2(pdes[1], STDOUT_FILENO);
                               (void)close(pdes[1]);
                       }
                       dup2(STDOUT_FILENO, STDERR_FILENO); /* stderr too! */
                       (void)close(pdes[0]);
               } else {
                       if (pdes[0] != STDIN_FILENO) {
                               dup2(pdes[0], STDIN_FILENO);
                               (void)close(pdes[0]);
                       }
                       (void)close(pdes[1]);
               }
               execv(gargv[0], gargv);
               _exit(1);
       }
       /* parent; assume fdopen can't fail...  */
       if (*type == 'r') {
               iop = fdopen(pdes[0], type);
               (void)close(pdes[1]);
       } else {
               iop = fdopen(pdes[1], type);
               (void)close(pdes[0]);
       }
       pids[fileno(iop)] = pid;

pfree:  for (argc = 1; gargv[argc] != NULL; argc++)
               free(gargv[argc]);

       return (iop);
}

int
ftpd_pclose(iop)
       FILE *iop;
{
       int fdes, omask, status;
       pid_t pid;

       /*
        * pclose returns -1 if stream is not associated with a
        * `popened' command, or, if already `pclosed'.
        */
       if (pids == 0 || pids[fdes = fileno(iop)] == 0)
               return (-1);
       (void)fclose(iop);
       omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP));
       while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR)
               continue;
       (void)sigsetmask(omask);
       pids[fdes] = 0;
       if (pid < 0)
               return (pid);
       if (WIFEXITED(status))
               return (WEXITSTATUS(status));
       return (1);
}