date and time created 92/07/09 14:47:41 by pendry

[unix-history] / usr / src / sbin / mount_portal / mount_portal.c

/*
* Copyright (c) 1992 The Regents of the University of California
* Copyright (c) 1990, 1992 Jan-Simon Pendry
* All rights reserved.
*
* This code is derived from software donated to Berkeley by
* Jan-Simon Pendry.
*
* %sccs.include.redist.c%
*
*      @(#)mount_portal.c      1.1 (Berkeley) %G%
*
* $Id: portald.c,v 1.3 1992/05/27 07:09:27 jsp Exp jsp $
*/

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/wait.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/syslog.h>
#include <sys/mount.h>

#include "pathnames.h"
#include "portald.h"

static sig_atomic_t readcf;     /* Set when SIGHUP received */

static void sigchld(sig)
int sig;
{
       pid_t pid;

       while ((pid = waitpid((pid_t) -1, (int *) 0, WNOHANG)) > 0)
               ;
       if (pid < 0)
               syslog(LOG_WARNING, "waitpid: %s", strerror(errno));
}

int main(c, v)
int c;
char *v[];
{
       struct portal_args args;
       struct sockaddr_un un;
       char *conf;
       char *mountpt;
       int mntflags = 0;
       int usage = 0;
       char tag[32];

       qelem q;
       int rc;
       int so;

       /*
        * Crack command line args
        */
       int ch;

       while ((ch = getopt(c, v, "F:")) != EOF) {
               switch (ch) {
               case 'F':
                       mntflags = atoi(optarg);
                       break;
               default:
                       usage = 1;
                       break;
               }
       }

       if (optind != (c - 2))
               usage = 1;

       if (usage) {
               fprintf(stderr, "Usage: mount_portal [ fsoptions ] config mount-point\n");
               exit(1);
       }

       /*
        * Get config file and mount point
        */
       conf = v[optind];
       mountpt = v[optind+1];

       /*
        * Construct the listening socket
        */
       un.sun_family = AF_UNIX;
       if (sizeof(_PATH_TMPPORTAL) >= sizeof(un.sun_path)) {
               fprintf(stderr, "mount_portal: portal socket name too long\n");
               exit(1);
       }
       strcpy(un.sun_path, _PATH_TMPPORTAL);
       mktemp(un.sun_path);
       un.sun_len = strlen(un.sun_path);

       so = socket(AF_UNIX, SOCK_STREAM, 0);
       if (so < 0) {
               fprintf(stderr, "mount_portal: socket: %s\n", strerror(errno));
               exit(1);
       }
       (void) unlink(un.sun_path);
       if (bind(so, (struct sockaddr *) &un, sizeof(un)) < 0) {
               fprintf(stderr, "mount_portal: bind: %s\n", strerror(errno));
               exit(1);
       }
       (void) unlink(un.sun_path);

       (void) listen(so, 5);

       args.pa_socket = so;
       sprintf(tag, "portal:%d", getpid());
       args.pa_config = tag;

       rc = mount(MOUNT_PORTAL, mountpt, mntflags, &args);
       if (rc < 0) {
               fprintf(stderr, "mount_portal: mount: %s\n", strerror(errno));
               exit(1);
       }

#ifdef notdef
       /*
        * Everything is ready to go - now is a good time to fork
        */
       daemon(0, 0);
#endif

       /*
        * Start logging (and change name)
        */
       openlog("portald", LOG_CONS|LOG_PID, LOG_DAEMON);

       q.q_forw = q.q_back = &q;
       readcf = 1;

       signal(SIGCHLD, sigchld);

       /*
        * Just loop waiting for new connections and activating them
        */
       for (;;) {
               struct sockaddr_un un2;
               int len2 = sizeof(un2);
               int so2;
               pid_t pid;
               fd_set fdset;
               int rc;

               /*
                * Check whether we need to re-read the configuration file
                */
               if (readcf) {
                       readcf = 0;
                       conf_read(&q, conf);
                       continue;
               }
       
               /*
                * Accept a new connection
                * Will get EINTR if a signal has arrived, so just
                * ignore that error code
                */
               FD_SET(so, &fdset);
               rc = select(so+1, &fdset, (void *) 0, (void *) 0, (void *) 0);
               if (rc < 0) {
                       if (errno == EINTR)
                               continue;
                       syslog(LOG_ERR, "select: %s", strerror(errno));
                       exit(1);
               }
               if (rc == 0)
                       break;
               so2 = accept(so, (struct sockaddr *) &un2, &len2);
               if (so2 < 0) {
                       /*
                        * The unmount function does a shutdown on the socket
                        * which will generated ECONNABORTED on the accept.
                        */
                       if (errno == ECONNABORTED)
                               break;
                       if (errno != EINTR) {
                               syslog(LOG_ERR, "accept: %s", strerror(errno));
                               exit(1);
                       }
                       continue;
               }

               /*
                * Now fork a new child to deal with the connection
                */
#ifdef notdef
       eagain:;
               switch (pid = fork()) {
               case -1:
                       if (errno == EAGAIN) {
                               sleep(1);
                               goto eagain;
                       }
                       syslog(LOG_ERR, "fork: %s", strerror(errno));
                       break;
               case 0:
                       (void) close(so);
                       activate(&q, so2);
                       break;
               default:
                       (void) close(so2);
                       break;
               }
#endif
               activate(&q, so2);
       }
       syslog(LOG_INFO, "%s unmounted", mountpt);
       exit(0);
}