/*
 *  dropnroll
 *
 *  Copyright (C) 2009-2015 Christian Pointner <equinox@spreadspace.org>
 *
 *  This file is part of dropnroll.
 *
 *  dropnroll 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 3 of the License, or
 *  any later version.
 *
 *  dropnroll 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 dropnroll. If not, see <http://www.gnu.org/licenses/>.
 */

#include "datatypes.h"

#include <sys/un.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/inotify.h>

#include "log.h"

#include "utils.h"

int init_command_socket(const char* path)
{
  int fd = socket(AF_UNIX, SOCK_STREAM, 0);
  if(fd < 0) {
    log_printf(ERROR, "unable to open socket: %s", strerror(errno));
    return -1;
  }

  struct sockaddr_un local;
  local.sun_family = AF_UNIX;
  if(sizeof(local.sun_path) <= strlen(path)) {
    log_printf(ERROR, "socket path is to long (max %d)", sizeof(local.sun_path)-1);
    return -1;
  }
  strcpy(local.sun_path, path);
  unlink(local.sun_path);
  int len = SUN_LEN(&local);
  int ret = bind(fd, (struct sockaddr*)&local, len);
  if(ret) {
    log_printf(ERROR, "unable to bind to '%s': %s", local.sun_path, strerror(errno));
    return -1;
  }

  ret = listen(fd, 4);
  if(ret) {
    log_printf(ERROR, "unable to listen on command socket: %s", local.sun_path, strerror(errno));
    return -1;
  }

  log_printf(INFO, "now listening on %s for incoming commands", path);

  return fd;
}

int connect_command_socket(const char* path)
{
  int fd = socket(AF_UNIX, SOCK_STREAM, 0);
  if(fd < 0) {
    log_printf(ERROR, "unable to open socket: %s", strerror(errno));
    return -1;
  }

  struct sockaddr_un remote;
  remote.sun_family = AF_UNIX;
  if(sizeof(remote.sun_path) <= strlen(path)) {
    log_printf(ERROR, "socket path is to long (max %d)", sizeof(remote.sun_path)-1);
    return -1;
  }
  strcpy(remote.sun_path, path);
  int len = SUN_LEN(&remote);
  int ret = connect(fd, (struct sockaddr*)&remote, len);
  if(ret) {
    log_printf(ERROR, "unable to connect to '%s': %s", remote.sun_path, strerror(errno));
    return -1;
  }

  return fd;
}

int send_string(int fd, const char* string)
{
  int len = strlen(string);
  int offset = 0;
  int ret;
  for(;;) {
    ret = write(fd, &string[offset], len - offset);
    if(ret < 0) {
      if(errno != EINTR)
        return ret;

      ret = 0;
    }

    offset += ret;
    if(offset+1 >= len)
      break;
  }
  return ret;
}

int create_inotify()
{
  int fd = inotify_init();
  if(fd < 0) {
    log_printf(ERROR, "error at inotify_init: %s", strerror(errno));
    return -1;
  }

  int fs_flags = fcntl(fd, F_GETFL);
  if(fs_flags == -1) {
    log_printf(ERROR, "inotify init failed (fcntl read flags error: %s)", strerror(errno));
    return -1;
  }
  if(fcntl(fd, F_SETFL, fs_flags | O_NONBLOCK) == -1) {
    log_printf(ERROR, "inotify init failed (fcntl write flags error: %s)", strerror(errno));
    return -1;
  }

  int fd_flags = fcntl(fd, F_GETFD);
  if(fd_flags == -1) {
    log_printf(ERROR, "inotify init failed (fcntl read flags error: %s)", strerror(errno));
    return -1;
  }
  if(fcntl(fd, F_SETFD, fd_flags | FD_CLOEXEC) == -1) {
    log_printf(ERROR, "inotify init failed (fcntl write flags error: %s)", strerror(errno));
    return -1;
  }

  return fd;
}