path: root/apps/sympathy.c

/*
 * sympathy.c:
 *
 * Copyright (c) 2008 James McKenzie <james@fishsoup.dhs.org>,
 * All rights reserved.
 *
 */

static char rcsid[] =
  "$Id$";

/*
 * $Log$
 * Revision 1.32  2008/03/03 06:04:42  james
 * *** empty log message ***
 *
 * Revision 1.31  2008/03/03 06:04:18  james
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 *
 * Revision 1.30  2008/03/02 10:38:18  james
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 *
 * Revision 1.29  2008/03/02 10:37:56  james
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 *
 * Revision 1.28  2008/03/02 10:27:24  james
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 *
 * Revision 1.27  2008/03/02 09:55:37  james
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 *
 * Revision 1.26  2008/02/29 14:55:09  james
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 *
 * Revision 1.25  2008/02/28 22:43:25  james
 * *** empty log message ***
 *
 * Revision 1.24  2008/02/28 22:00:42  james
 * *** empty log message ***
 *
 * Revision 1.23  2008/02/28 16:57:51  james
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 *
 * Revision 1.22  2008/02/28 01:47:44  james
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 *
 * Revision 1.21  2008/02/27 16:01:24  james
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 *
 * Revision 1.20  2008/02/27 10:00:34  james
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 *
 * Revision 1.19  2008/02/27 09:47:05  james
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 *
 * Revision 1.18  2008/02/27 09:42:53  james
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 *
 * Revision 1.17  2008/02/27 09:42:21  james
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 *
 * Revision 1.16  2008/02/27 01:31:38  james
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 *
 * Revision 1.15  2008/02/27 01:31:14  james
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 *
 * Revision 1.14  2008/02/24 00:43:55  james
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 *
 * Revision 1.13  2008/02/24 00:42:53  james
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 *
 * Revision 1.12  2008/02/23 11:48:52  james
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 * Revision 1.11  2008/02/20 20:16:07  james
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 *
 * Revision 1.10  2008/02/20 19:44:37  james
 * @@
 *
 * Revision 1.9  2008/02/20 18:49:11  staffcvs
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 *
 * Revision 1.8  2008/02/20 18:33:37  james
 * *** empty log message ***
 *
 * Revision 1.7  2008/02/20 18:31:44  james
 * *** empty log message ***
 *
 * Revision 1.6  2008/02/20 17:18:33  james
 * *** empty log message ***
 *
 * Revision 1.5  2008/02/20 15:50:14  james
 * *** empty log message ***
 *
 * Revision 1.4  2008/02/20 02:11:35  james
 * *** empty log message ***
 *
 * Revision 1.3  2008/02/14 02:46:44  james
 * *** empty log message ***
 *
 * Revision 1.2  2008/02/14 00:57:58  james
 * *** empty log message ***
 *
 * Revision 1.1  2008/02/05 14:25:49  james
 * *** empty log message ***
 *
 */

#include <sys/types.h>
#include <stdarg.h>
#include <sympathy.h>
#include <stdlib.h>
#include <sys/utsname.h>
#include <sys/stat.h>
#include <dirent.h>
#include <string.h>
#include <strings.h>
#include <malloc.h>
#include <fcntl.h>
#include <sys/resource.h>
#include <sys/wait.h>


#include "mainloop.h"

extern void usage (void);
static char hostname[1024];

char *socket_dirs[] =
  { "~/.sympathy", "~/sympathy", "/etc/sympathy", "/var/sympathy", NULL };

int
safe_atoi (char *a)
{
  char *end;
  int ret;

  if (!a)
    return -1;

  ret = (int) strtol (a, &end, 0);

  if (end == a)
    return -1;

  return ret;
}

char *
fatal_moan (char *fmt, ...)
{
  va_list ap;


  va_start (ap, fmt);
  vfprintf (stderr, fmt, ap);
  va_end (ap);

  putc ('\n', stderr);
  exit (1);
}

static void
sigchld (int dummy)
{
  int status;
  wait3 (&status, WNOHANG, NULL);
}

/*Dispell zombies, from for example log compression*/
void
garlic (void)
{
  struct sigaction sa;

  sa.sa_handler = sigchld;
  sa.sa_flags = SA_RESTART;
  sigaction (SIGCHLD, &sa, NULL);
}

char *
teedious_snprintf (char *fmt, va_list ap)
{
  va_list aq;
  int size = 1024;
  char *buf = malloc (size);
  int n;

  if (!buf)
    fatal_moan ("malloc failed");

  while (1)
    {

      va_copy (aq, ap);
      n = vsnprintf (buf, size, fmt, aq);
      va_end (aq);

      if (n > -1 && n < (size))
        return buf;

      if (n > -1)               /* glibc 2.1 */
        size = n + 1;
      else                      /* glibc 2.0 */
        size *= 2;              /* twice the old size */

      buf = realloc (buf, size);

      if (!buf)
        fatal_moan ("malloc failed");
    }

}

char *
gloo_paths (char *dir, char *leaf)
{
  int i;
  char *ret, *ptr;
  if (!dir)
    dir = "";
  if (!leaf)
    leaf = "";
  ret = ptr = malloc (strlen (dir) + strlen (leaf) + 2);

  while (*dir)
    *(ptr++) = *(dir++);
  *(ptr++) = '/';
  while (*leaf)
    *(ptr++) = *(leaf++);
  *ptr = 0;

  return ret;
}


/*make the path in fmt from home (hence the name) */
char *
mome (char *fmt, ...)
{
  char *ret, *home, *leaf;
  va_list ap;


  home = getenv ("HOME");
  if (!home)
    return NULL;

  if (fmt)
    {
      va_start (ap, fmt);
      leaf = teedious_snprintf (fmt, ap);
      va_end (ap);
    }
  else
    {
      leaf = NULL;
    }

  ret = gloo_paths (home, leaf);
  if (leaf)
    free (leaf);

  return ret;
}


Socket *
find_socket (char *fmt, ...)
{
  Socket *ret;
  char *path, *leaf, *h, **ptr;
  va_list ap;


  if (fmt)
    {
      va_start (ap, fmt);
      leaf = teedious_snprintf (fmt, ap);
      va_end (ap);
    }
  else
    {
      leaf = NULL;
    }


  for (ptr = socket_dirs; *ptr; ptr++)
    {
      if (**ptr == '~')
        {
          h = mome (*ptr + 1);
        }
      else
        {
          h = *ptr;
        }

      if (!h)
        continue;


      path = gloo_paths (h, leaf);
      if (**ptr == '~')
        free (h);

      ret = socket_connect (path);

      free (path);

      if (ret)
        {
          free (leaf);
          return ret;
        }

    }

  free (leaf);
  return NULL;

}



int
list_sockets_in_dir (char *sockdir)
{
  struct dirent *ent;
  struct stat buf;
  char *sn = NULL;
  Socket *s;
  DIR *dir = opendir (sockdir);



  int hostname_len = strlen (hostname);

  if (!dir)
    return;

  rewinddir (dir);


  while ((ent = readdir (dir)))
    {
      sn = gloo_paths (sockdir, ent->d_name);
      if (stat (sn, &buf) || (!S_ISSOCK (buf.st_mode)))
        {
          free (sn);
          continue;
        }

      s = socket_connect (sn);

      if (s)
        {
          printf ("\t%s 	(Active)\n", sn);
          socket_free (s);
        }
      else
        {
          if (strncmp (ent->d_name, hostname, hostname_len))
            {
              printf ("\t%s	(Unknown - not this host)\n", sn);
            }
          else
            {
              printf ("\t%s	(Dead, wiped)\n", sn);
              unlink (sn);
            }
        }

      free (sn);
    }

  closedir (dir);

  return 0;
}

int
list_sockets (void)
{
  char **ptr, *h;


  for (ptr = socket_dirs; *ptr; ptr++)
    {
      if (**ptr == '~')
        {
          h = mome (*ptr + 1);
        }
      else
        {
          h = *ptr;
        }

      if (!h)
        continue;

      list_sockets_in_dir (h);

      if (**ptr == '~')
        free (h);

    }

  return 0;
}


void
get_hostname (void)
{
  struct utsname name;

  if (uname (&name))
    {
      strcpy (hostname, "unknown.");
      return;
    }


  strcpy (hostname, name.nodename);
  strcat (hostname, ".");
}


int
main (int argc, char *argv[])
{
  int c;
  extern char *optarg;
  extern int optind, opterr, optopt;
  CRT_Pos size = { VT102_COLS_80, VT102_ROWS_24 };

  int csnok_pipe[2] = { 0 };
  int csnok = 0;

  int oflags[128];
  char *oargs[128];

  Socket *server_socket = NULL, *client_socket = NULL;
  ANSI *ansi = NULL;
  TTY *tty = NULL;
  Log *log = NULL;

  int history = 200;
  int pid;

  char *pid_file = NULL;

  get_hostname ();

  memset (oflags, 0, sizeof (oflags));
  memset (oargs, 0, sizeof (oargs));
  while ((c = getopt (argc, argv, "RP:vw:utscr:lKHd:pb:fL:Fk:n:")) != EOF)
    {
      switch (c)
        {
        case ':':
        case 'h':
        case '?':
          usage ();
        default:
          if ((c > 64) && (c < 91))
            {
              oflags[c]++;
              oargs[c] = optarg;
            }
          else if ((c > 96) && (c < 123))
            {
              oflags[c]++;
              oargs[c] = optarg;
            }
          else
            {
              fprintf (stderr, "unknown option %c\n", c);
              usage ();
            }
        }

    }

  /*Compatability for screen's ls */
  if (oflags['l'])
    oflags['s'] = 0;


  {
    int sum = 0;
    sum += oflags['t'];
    sum += (oflags['s'] || oflags['c']) ? 1 : 0;
    sum += oflags['r'];
    sum += oflags['l'];
    sum += oflags['v'];

    if (!sum)
      {
        /*If no mode is specified behave like screen */
        oflags['s']++;
        oflags['c']++;
        sum++;
      }

    if (sum != 1)
      fatal_moan
        ("specifiy exactly one of ( -c and or -s ), -t, -r, -l and -v");
  }

  if (oflags['v'])
    {
      fprintf (stderr, "Version: %s\n", libsympathy_version ());
      fprintf (stderr, "Version: %s\n", rcsid);
      return 0;
    }

  if (oflags['l'])
    return list_sockets ();


  if (oflags['r'] && oflags['k'])
    fatal_moan ("-k is incompatible with -r");


  if (oflags['n'])
    {
      history = safe_atoi (oargs['n']);
      if (history < 0)
        fatal_moan ("cannot parse -n %s as an integer", oargs['n']);

      if (!history)
        fatal_moan ("agrument to -n must be greater than zero");
    }

  /*Fold -r implies -c */
  if (oflags['r'])
    oflags['c']++;

  if (oflags['p'] && oflags['d'])
    fatal_moan ("-p incompatible with -d");


  if (oflags['c'] && oflags['s'] && oflags['F'])
    fatal_moan ("-F is incompatible with -c -s");

  /*implement server and client: this process forks. The parent */
  /*becomes the client and the child forks again to become the */
  /*server. If there's no -k argument the client (parent) needs */
  /*to find out the pid of the server, we use a pipe */

  if (oflags['s'] && oflags['c'])
    {
      if (!oflags['k'])
        {
          csnok++;
          pipe (csnok_pipe);
        }

      switch (pid = fork ())
        {
        case 0:                /*child becomes the server */
          oflags['c'] = 0;
          oflags['H'] = 0;

          if (csnok)
            close (csnok_pipe[0]);
          break;
        case -1:
          fatal_moan ("fork failed");
        default:               /*parent becomes client */
          oflags['s'] = 0;
          oflags['K'] = 0;
          oflags['d'] = 0;
          oflags['p'] = 0;
          oflags['b'] = 0;
          oflags['f'] = 0;
          oflags['L'] = 0;
          oflags['R'] = 0;
          oflags['P'] = 0;
          oflags['n'] = 0;
          oflags['w'] = 0;

          /*Collect the child */
          waitpid (pid, NULL, 0);

          /*if there was no k argument we need to find the */
          /*pid of the server process so that we can work out */
          /*what the socket is called. The server tells us on */
          /*a pipe */

          if (csnok)
            {
              close (csnok_pipe[1]);

              if (read (csnok_pipe[0], &pid, sizeof (pid)) != sizeof (pid))
                fatal_moan ("Failed to receive pid of server process");

              close (csnok_pipe[0]);

              oargs['k'] = mome ("/.sympathy/%s%d", hostname, pid);
              oflags['k']++;
            }
        }
    }


  if (oflags['c'] && !oflags['k'] && !oflags['r'])
    fatal_moan ("-c requires a socket to be specified with -s or -k or -r");

  if ((oflags['p'] || oflags['d'] || oflags['K'] || oflags['b'] || oflags['f']
       || oflags['L'] || oflags['R'] || oflags['P']) && oflags['c'])
    fatal_moan
      ("-c or -r are incompatible with -p, -d, -K, -b, -f, -R, -P or -L");

  if (oflags['t'] || oflags['s'])
    {
      if (!oflags['p'] && !oflags['d'])
        oflags['p']++;
    }

  if (oflags['w'])
    {
      char buf[128], *ptr;
      strcpy (buf, oargs['w']);
      ptr = index (buf, 'x');
      if (ptr)
        {
          *ptr = 0;
          ptr++;
          size.y = safe_atoi (ptr);
        }
      size.x = safe_atoi (buf);

      if ((size.x > VT102_MAX_COLS) || (size.x < 1))
        fatal_moan ("-w requires a width between 1 and %d\n", VT102_MAX_COLS);

      if ((size.y > VT102_MAX_ROWS) || (size.y < 1))
        fatal_moan ("-w requires a height between 1 and %d\n",
                    VT102_MAX_ROWS);

    }

  if (oflags['s'] && !oflags['F'])
    {
      /*nochdir incase socket is relative path, unlink then will fail */
      daemon (1, 0);

    }


  if (oflags['s'])
    {
      char *path;
      path = mome ("/.sympathy");
      mkdir (path, 0700);
      free (path);


      if (!oflags['k'])
        {
          pid = getpid ();

          oargs['k'] = mome ("/.sympathy/%s%d", hostname, pid);
          oflags['k']++;
        }

      server_socket = socket_listen (oargs['k']);

      /*Tell our parent's parent what our pid is */
      if (csnok)
        {
          pid = getpid ();

          write (csnok_pipe[1], &pid, sizeof (pid));
          close (csnok_pipe[1]);
        }

      if (!server_socket)
        fatal_moan ("failed to create socket %s for listening", oargs['k']);

    }

  if (oflags['s'] || oflags['t'])
    {
      if (oflags['P'])
        {
          FILE *fp;
          pid_file = oargs['P'];
          fp = fopen (pid_file, "w");
          if (fp)
            {
              fprintf (fp, "%d", getpid ());
              fclose (fp);
            }
        }

      if (oflags['L'])
        {
          log = file_log_new (oargs['L'], oflags['R']);
          if (!log)
            fatal_moan ("unable to access log file %s", oargs['L']);
        }

      if (oflags['p'])
        {
          tty = ptty_open (NULL, NULL, &size);
          if (!tty)
            fatal_moan ("unable to open a ptty");
        }
      else
        {
          /*HACK-- check that console=device does not occur in */
          /*/proc/cmdline */
          if (!oargs['d'])
            fatal_moan ("no argument to -d");

          {
            char kernel_cmdline[4096] = { 0 };
            char search_string[1024] = "console=";
            char *ptr = oargs['d'];
            int fd;

            if (!strncmp ("/dev/", ptr, 5))
              ptr += 5;

            strcat (search_string, ptr);

            fd = open ("/proc/cmdline", O_RDONLY);
            read (fd, kernel_cmdline, sizeof (kernel_cmdline));
            close (fd);

            kernel_cmdline[sizeof (kernel_cmdline) - 1] = 0;

            if (strstr (kernel_cmdline, search_string))
              fatal_moan ("/proc/cmdline contains %s", search_string);
          }

          tty =
            serial_open (oargs['d'],
                         oflags['K'] ? SERIAL_LOCK_ACTIVE :
                         SERIAL_LOCK_PASSIVE);
          if (!tty)
            fatal_moan ("unable to open serial port %s", oargs['d']);
        }

      if (oflags['b'])
        {
          int baud = safe_atoi (oargs['b']);

          if (baud < 0)
            fatal_moan ("Unable to parse baudrate %s", oargs['b']);

          tty_set_baud (tty, baud);

        }

      tty_set_flow (tty, oflags['f'] ? 1 : 0);
    }


  if (oflags['r'])
    {
      char *id = oargs['r'];

      if (!id)
        fatal_moan ("-r requires an argument");

      if (safe_atoi (id) > 0)
        {
          client_socket = find_socket ("%s%d", hostname, safe_atoi (id));
        }
      else
        {
          client_socket = find_socket ("%s", id);
        }

      if (!client_socket)
        fatal_moan ("failed to find socket %s", oargs['r']);

    }
  else if (oflags['c'])
    {
      client_socket = socket_connect (oargs['k']);

      if (!client_socket)
        fatal_moan ("failed to connect to socket %s", oargs['k']);

    }


  if (oflags['c'] || oflags['t'])
    {

      if (oflags['H'])
        {
          ansi = ansi_new_html (stdout);
        }
      else
        {
          terminal_register_handlers ();
          ansi =
            ansi_new_from_terminal (terminal_open (0, 1),
                                    oflags['u'] ? 0 : 1);
          ansi->reset (ansi, NULL);
        }
    }

  mainloop (tty, server_socket, client_socket, ansi, log, history, &size);

  if (ansi)
    {
      ansi->close (ansi);
      terminal_atexit ();
    }

  if (tty)
    tty->close (tty);

  if (log)
    log->close (log);
  if (server_socket)
    socket_free (server_socket);
  if (client_socket)
    socket_free (client_socket);

  if (pid_file)
    unlink (pid_file);

  if (!oflags['H'])
    printf ("you have now exited sympathy\n");
  return 0;
}