#include <unistd.h>
#include "httpd.h"
#include "http_config.h"
#include "http_protocol.h"
#include "ap_config.h"
#include "ap_listen.h"
#include "apr_strings.h"
#include "http_log.h"

static ap_listen_rec *
alloc_unix_listener (process_rec * process, const char *path,
		     const char *proto)
{
  struct sockaddr_un sun = {
    .sun_family = AF_UNIX,
  };
  apr_os_sock_info_t si;
  ap_listen_rec *rec;
  apr_status_t rv;
  int one = 1;
  int fd;

  apr_cpystrn (sun.sun_path, path, sizeof (sun.sun_path));

  rec = apr_palloc (process->pool, sizeof (*rec));
  rec->protocol = apr_pstrdup (process->pool, proto);
  rec->accept_func = NULL;
  rec->next = NULL;
  rec->active = 1;

  if (unlink (sun.sun_path))
    {
      ap_log_perror (APLOG_MARK, APLOG_CRIT, APR_EGENERAL, process->pool,
		     APLOGNO (10100) "unlink failed: %s", strerror (errno));
      return NULL;
    }

  fd = socket (AF_UNIX, SOCK_STREAM, 0);
  if (fd == -1)
    {
      ap_log_perror (APLOG_MARK, APLOG_CRIT, APR_EGENERAL, process->pool,
		     APLOGNO (10101) "socket failed: %s", strerror (errno));
      return NULL;
    }

  if (setsockopt (fd, SOL_SOCKET, SO_REUSEPORT,
		  (void *) &one, sizeof (one)) < 0)
    {
      ap_log_perror (APLOG_MARK, APLOG_CRIT, APR_EGENERAL, process->pool,
		     APLOGNO (10102) "setsockopt failed: %s",
		     strerror (errno));
      close (fd);
      return NULL;
    }

  /* apr_socket_bind() is not used because apr_sockaddr_t is not compatible
   * with sockaddr_un
   */
  if (bind (fd, (struct sockaddr *) &sun, sizeof (sun)))
    {
      ap_log_perror (APLOG_MARK, APLOG_CRIT, APR_EGENERAL, process->pool,
		     APLOGNO (10103) "bind failed: %s", strerror (errno));
      close (fd);
      return NULL;
    }

  /* FIXME (ugly hack): configure fake socket information to allow
   * ap_setup_listeners() to set the protocol of servers.
   * I don't know if it interacts well with other parts of the codebase
   * (I haven't even checked properly the whole server/listen.c file!)
   */
  si.os_sock = &fd;
  si.remote = NULL;
  si.local = NULL;
  si.family = APR_INET;
  si.type = SOCK_STREAM;
  si.protocol = APR_PROTO_TCP;

  rv = apr_os_sock_make (&rec->sd, &si, process->pool);
  if (rv != APR_SUCCESS)
    {
      ap_log_perror (APLOG_MARK, APLOG_CRIT, APR_EGENERAL, process->pool,
		     APLOGNO (10104) "apr_os_sock_make failed (%d)", fd);
      close (fd);
      return NULL;
    }

  rv = apr_socket_listen (rec->sd, 10);
  if (rv != APR_SUCCESS)
    {
      ap_log_perror (APLOG_MARK, APLOG_CRIT, rv, process->pool,
		     APLOGNO (10105) "apr_socket_listen failed (%d)", fd);
      return NULL;
    }

  rv = apr_socket_addr_get (&rec->bind_addr, APR_LOCAL, rec->sd);
  if (rv != APR_SUCCESS)
    {
      ap_log_perror (APLOG_MARK, APLOG_CRIT, rv, process->pool,
		     APLOGNO (10106) "apr_socket_addr_get failed (%d)", fd);
      return NULL;
    }

  /* TODO: implement useful parts of make_sock (server/listen.c) */

  return rec;
}


static const char *
set_listen_path (cmd_parms * cmd, void *cfg, const char *path,
		 const char *proto)
{
  ap_listen_rec *last;
  ap_listen_rec *new;
  apr_status_t rv;
  const char *err;

  err = ap_check_cmd_context (cmd, GLOBAL_ONLY);
  if (err)
    {
      return err;
    }

  if (strcmp (proto, "http") && strcmp (proto, "https"))
    {
      return "Proto must be either 'http' or 'https'";
    }

  new = alloc_unix_listener (cmd->server->process, path, proto);
  if (!new)
    {
      return "Failed to listen on Unix socket";
    }

  last = ap_listeners;

  while (last && last->next)
    {
      last = last->next;
    }

  if (!last)
    {
      ap_listeners = new;
    }
  else
    {
      last->next = new;
    }

  return NULL;
}

static const command_rec directives[] = {
  AP_INIT_TAKE2 ("ListenUnixPath", set_listen_path, NULL, RSRC_CONF,
		 "Listen to Unix socket"),
  {NULL},
};


module AP_MODULE_DECLARE_DATA unix_socket_module = {
  STANDARD20_MODULE_STUFF,
  NULL,
  NULL,
  NULL,
  NULL,
  directives,
  NULL,
};