/*

  chronyd/chronyc - Programs for keeping computer clocks accurate.

 **********************************************************************

 * Copyright (C) Miroslav Lichvar  2009

 * 

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of version 2 of the GNU General Public License as

 * published by the Free Software Foundation.

 * 

 * 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 Street, Fifth Floor, Boston, MA  02110-1301, USA.

 * 

 **********************************************************************

  =======================================================================

  Unix domain socket refclock driver.

  */

#include "config.h"

#include "sysincl.h"

#include "refclock.h"

#include "logging.h"

#include "util.h"

#include "sched.h"

#define SOCK_MAGIC 0x534f434b

struct sock_sample {

  /* Time of the measurement (system time) */

  struct timeval tv;

  /* Offset between the true time and the system time (in seconds) */

  double offset;

  /* Non-zero if the sample is from a PPS signal, i.e. another source

     is needed to obtain seconds */

  int pulse;

  /* 0 - normal, 1 - insert leap second, 2 - delete leap second */

  int leap;

  /* Padding, ignored */

  int _pad;

  /* Protocol identifier (0x534f434b) */

  int magic;

};

static void read_sample(int sockfd, int event, void *anything)

{

  struct sock_sample sample;

  struct timespec ts;

  RCL_Instance instance;

  int s;

  instance = (RCL_Instance)anything;

  s = recv(sockfd, &sample, sizeof (sample), 0);

  if (s < 0) {

    DEBUG_LOG("Could not read SOCK sample : %s", strerror(errno));

    return;

  }

  if (s != sizeof (sample)) {

    DEBUG_LOG("Unexpected length of SOCK sample : %d != %ld",

              s, (long)sizeof (sample));

    return;

  }

  if (sample.magic != SOCK_MAGIC) {

    DEBUG_LOG("Unexpected magic number in SOCK sample : %x != %x",

              (unsigned int)sample.magic, (unsigned int)SOCK_MAGIC);

    return;

  }

  UTI_TimevalToTimespec(&sample.tv, &ts);

  UTI_NormaliseTimespec(&ts);

  if (sample.pulse) {

    RCL_AddPulse(instance, &ts, sample.offset);

  } else {

    RCL_AddSample(instance, &ts, sample.offset, sample.leap);

  }

}

static int sock_initialise(RCL_Instance instance)

{

  struct sockaddr_un s;

  int sockfd;

  char *path;

  RCL_CheckDriverOptions(instance, NULL);

  path = RCL_GetDriverParameter(instance);

  s.sun_family = AF_UNIX;

  if (snprintf(s.sun_path, sizeof (s.sun_path), "%s", path) >= sizeof (s.sun_path)) {

    LOG_FATAL("Path %s too long", path);

    return 0;

  }

  sockfd = socket(AF_UNIX, SOCK_DGRAM, 0);

  if (sockfd < 0) {

    LOG_FATAL("socket() failed");

    return 0;

  }

  UTI_FdSetCloexec(sockfd);

  unlink(path);

  if (bind(sockfd, (struct sockaddr *)&s, sizeof (s)) < 0) {

    LOG_FATAL("bind(%s) failed : %s", path, strerror(errno));

    return 0;

  }

  RCL_SetDriverData(instance, (void *)(long)sockfd);

  SCH_AddFileHandler(sockfd, SCH_FILE_INPUT, read_sample, instance);

  return 1;

}

static void sock_finalise(RCL_Instance instance)

{

  int sockfd;

  sockfd = (long)RCL_GetDriverData(instance);

  SCH_RemoveFileHandler(sockfd);

  close(sockfd);

}

RefclockDriver RCL_SOCK_driver = {

  sock_initialise,

  sock_finalise,

  NULL

};