/*
 * Service monitor: notification module
 *
 * Nickolai Zeldovich <kolya@MIT.EDU>
 * February 2002
 */

#include <async.h>
#include "svcmon.h"

static const char zwrite_script_path[] = "/var/ops/svcmon/zwrite.sh";

static str zephyr_buf ("");
static timecb_t *zephyr_cb;

static str
notify_tostr (service *svc)
{
  strbuf m;

  m << svc->descr () << " is ";
  if (svc->ok ())
    m << "back up\n";
  else
    m << "down: " << svc->errmsg () << "\n";
  return m;
}

void
notify_cons (service *svc)
{
  warn << notify_tostr (svc);
}

static void
notify_zephyr_close (int s, bool ok)
{
  close (s);
}

static void
notify_zephyr_flush ()
{
  const char *argv[2];
  int fds[2];
  str buf = zephyr_buf;

  zephyr_cb = NULL;
  zephyr_buf = "";
  if (pipe (fds) < 0) {
    warn << "Failed to create pipe: " << strerror (errno) << "\n";
    return;
  }

  argv[0] = zwrite_script_path;
  argv[1] = NULL;

  make_async (fds[1]);
  close_on_exec (fds[1]);
  pid_t pid = spawn (argv[0], argv, fds[0]);
  close (fds[0]);
  if (pid < 0) {
    warn << "Failure spawning zwrite: " << strerror (errno) << "\n";
    close (fds[1]);
    return;
  }

  net_write (fds[1], strbuf (buf), wrap (&notify_zephyr_close, fds[1]));
}

void
notify_zephyr (service *svc)
{
  zephyr_buf = zephyr_buf << notify_tostr (svc);

  if (zephyr_cb == NULL)
    zephyr_cb = delaycb (2, wrap (&notify_zephyr_flush));
}