rssbgr.c

Go to the documentation of this file.

/*
 *  $Id: rssbgr.c,v 1.37 2006/04/17 22:45:19 ghost666 Exp $
 *
 *  rssbgr - RSS backgroud reader
 *  Copyright (C) 2005, 2006 Piotr 'GhosT' Wydrych
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

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

#include "share.h"
#include "execute.h"
#include "fetch.h"
#include "lockfile.h"
#include "md5.h"
#include "readconfig.h"
#include "replace_fields.h"
#include "signal.h"

#define FETCH_BUFFER_SIZE 10240
#define WRITE_BUFFER_SIZE 100

char *home; /* $HOME */

int main(void)
{
 pid_t child_pid, grandchild_pid;
 pthread_t *fetch_threads;
 int status;
 directory = (char *)malloc(PATH_MAX);
 lockfile = (char *)malloc(PATH_MAX);
 configfile = (char *)malloc(PATH_MAX);
 home = (char *)getenv("HOME");
 if (home == NULL) DIE("HOME variable not set. Program will exit.")
 sprintf(directory, "%s/" DIRECTORY, home);   directory = (char *)realloc(directory, strlen(directory)+1);
 sprintf(lockfile, "%s/" LOCKFILE, home);     lockfile = (char *)realloc(lockfile, strlen(lockfile)+1);
 sprintf(configfile, "%s/" CONFIGFILE, home); configfile = (char *)realloc(configfile, strlen(configfile)+1);
 i_am = I_AM_PARENT;
 unsigned int i;

 if ((child_pid = fork())<0)
  DIE("Cannot fork. Program will exit.")
 
 switch(child_pid)
 {
  case 0:
   i_am = I_AM_CHILD;
   DEBUG2("Child starts. PID: %i", (int) getpid())
   do
   {
    if ((grandchild_pid = fork())<0)
     DIE("Cannot fork. Program will exit.")
    switch(grandchild_pid)
    {
     case 0:
      i_am = I_AM_GRANDCHILD;
      set_signal_handlers();
      DEBUG2("Grandchild starts. PID: %i", (int) getpid())
      create_lockfile();
      readconfig();
      if (!config_items_count)
      {
       fprintf(stdout, "No valid entries in config file. Please run rssbgr-conf.\n");
       unlink(lockfile);
       _exit(1);
      }
      fetch_threads = (pthread_t *)malloc(config_items_count*sizeof(pthread_t));
      for (i=0; i<config_items_count; i++)
       pthread_create(&(fetch_threads[i]), NULL, fetch_thread, (void *)((size_t)i));
      check_lockfile();
      fprintf(stderr, "Lockfile violation.\n");
      for (i=0; i<config_items_count; i++)
       pthread_cancel(fetch_threads[i]);
      unlink(lockfile);
      DEBUG1("Grandchild ends")
      break;
     default:
      set_signal_handlers();
      waitpid(grandchild_pid, &status, 0);
      DEBUG2("Grandchild returned %i", status>>8)
      if (!status) fprintf(stderr, "RSS background reader will restart.\n");
    }
   } while(grandchild_pid && (!(status>>8)));
   if (grandchild_pid) DEBUG1("Child ends")
   break;
  default:
   DEBUG2("Parent starts. PID: %i", (int) getpid())
   sleep(1);
   DEBUG1("Parent ends")
 }
 return 0;
}

---