update_daemon2.php

   1 #!/usr/bin/php
   2 <?php
   3         set_include_path(get_include_path() . PATH_SEPARATOR . "include");
   4
   5         // This is an experimental multiprocess update daemon.
   6         // Some configurable variable may be found below.
   7
   8         declare(ticks = 1);
   9         chdir(dirname(__FILE__));
  10
  11         define('DISABLE_SESSIONS', true);
  12
  13         require_once "version.php";
  14
  15         if (strpos(VERSION, ".99") !== false || getenv('DAEMON_XDEBUG')) {
  16                 define('DAEMON_EXTENDED_DEBUG', true);
  17         }
  18
  19         define('PURGE_INTERVAL', 3600); // seconds
  20         define('MAX_CHILD_RUNTIME', 600); // seconds
  21
  22         require_once "sanity_check.php";
  23         require_once "config.php";
  24
  25         define('MAX_JOBS', 2);
  26         define('SPAWN_INTERVAL', DAEMON_SLEEP_INTERVAL);
  27
  28         if (!function_exists('pcntl_fork')) {
  29                 die("error: This script requires PHP compiled with PCNTL module.\n");
  30         }
  31
  32         require_once "db.php";
  33         require_once "db-prefs.php";
  34         require_once "functions.php";
  35         require_once "rssfuncs.php";
  36         require_once "lib/magpierss/rss_fetch.inc";
  37
  38         $children = array();
  39         $ctimes = array();
  40
  41         $last_checkpoint = -1;
  42
  43         function reap_children() {
  44                 global $children;
  45                 global $ctimes;
  46
  47                 $tmp = array();
  48
  49                 foreach ($children as $pid) {
  50                         if (pcntl_waitpid($pid, $status, WNOHANG) != $pid) {
  51
  52                                 if (file_is_locked("update_daemon-$pid.lock")) {
  53                                         array_push($tmp, $pid);
  54                                 } else {
  55                                         _debug("[reap_children] child $pid seems active but lockfile is unlocked.");
  56                                 }
  57                         } else {
  58                                 _debug("[reap_children] child $pid reaped.");
  59                                 unset($ctimes[$pid]);
  60                         }
  61                 }
  62
  63                 $children = $tmp;
  64
  65                 return count($tmp);
  66         }
  67
  68         function check_ctimes() {
  69                 global $ctimes;
  70
  71                 foreach (array_keys($ctimes) as $pid) {
  72                         $started = $ctimes[$pid];
  73
  74                         if (time() - $started > MAX_CHILD_RUNTIME) {
  75                                 _debug("[MASTER] child process $pid seems to be stuck, aborting...");
  76                                 posix_kill($pid, SIGKILL);
  77                         }
  78                 }
  79         }
  80
  81         function sigchld_handler($signal) {
  82                 $running_jobs = reap_children();
  83
  84                 _debug("[SIGCHLD] jobs left: $running_jobs");
  85
  86                 pcntl_waitpid(-1, $status, WNOHANG);
  87         }
  88
  89         function shutdown() {
  90                 if (file_exists(LOCK_DIRECTORY . "/update_daemon.lock"))
  91                         unlink(LOCK_DIRECTORY . "/update_daemon.lock");
  92         }
  93
  94         function task_shutdown() {
  95                 $pid = posix_getpid();
  96
  97                 if (file_exists(LOCK_DIRECTORY . "/update_daemon-$pid.lock"))
  98                         unlink(LOCK_DIRECTORY . "/update_daemon-$pid.lock");
  99         }
 100
 101         function sigint_handler() {
 102                 shutdown();
 103                 die("[SIGINT] removing lockfile and exiting.\n");
 104         }
 105
 106         function task_sigint_handler() {
 107                 task_shutdown();
 108                 die("[SIGINT] removing lockfile and exiting.\n");
 109         }
 110
 111         pcntl_signal(SIGCHLD, 'sigchld_handler');
 112
 113         if (file_is_locked("update_daemon.lock")) {
 114                 die("error: Can't create lockfile. ".
 115                         "Maybe another daemon is already running.\n");
 116         }
 117
 118         if (!pcntl_fork()) {
 119                 pcntl_signal(SIGINT, 'sigint_handler');
 120                 register_shutdown_function('shutdown');
 121
 122                 // Try to lock a file in order to avoid concurrent update.
 123                 $lock_handle = make_lockfile("update_daemon.lock");
 124
 125                 if (!$lock_handle) {
 126                         die("error: Can't create lockfile. ".
 127                                 "Maybe another daemon is already running.\n");
 128                 }
 129
 130                 while (true) { sleep(100); }
 131         }
 132
 133         // Testing database connection.
 134         // It is unnecessary to start the fork loop if database is not ok.
 135         $link = db_connect(DB_HOST, DB_USER, DB_PASS, DB_NAME);
 136
 137         if (!init_connection($link)) return;
 138
 139         db_close($link);
 140
 141         while (true) {
 142
 143                 // Since sleep is interupted by SIGCHLD, we need another way to
 144                 // respect the SPAWN_INTERVAL
 145                 $next_spawn = $last_checkpoint + SPAWN_INTERVAL - time();
 146
 147                 if ($next_spawn % 10 == 0) {
 148                         $running_jobs = count($children);
 149                         _debug("[MASTER] active jobs: $running_jobs, next spawn at $next_spawn sec.");
 150                 }
 151
 152                 if ($last_checkpoint + SPAWN_INTERVAL < time()) {
 153
 154                         check_ctimes();
 155                         reap_children();
 156
 157                         for ($j = count($children); $j < MAX_JOBS; $j++) {
 158                                 $pid = pcntl_fork();
 159                                 if ($pid == -1) {
 160                                         die("fork failed!\n");
 161                                 } else if ($pid) {
 162                                         _debug("[MASTER] spawned client $j [PID:$pid]...");
 163                                         array_push($children, $pid);
 164                                         $ctimes[$pid] = time();
 165                                 } else {
 166                                         pcntl_signal(SIGCHLD, SIG_IGN);
 167                                         pcntl_signal(SIGINT, 'task_sigint_handler');
 168
 169                                         register_shutdown_function('task_shutdown');
 170
 171                                         $my_pid = posix_getpid();
 172                                         $lock_filename = "update_daemon-$my_pid.lock";
 173
 174                                         $lock_handle = make_lockfile($lock_filename);
 175
 176                                         if (!$lock_handle) {
 177                                                 die("error: Can't create lockfile ($lock_filename). ".
 178                                                 "Maybe another daemon is already running.\n");
 179                                         }
 180
 181                                         // ****** Updating RSS code *******
 182                                         // Only run in fork process.
 183
 184                                         $start_timestamp = time();
 185
 186                                         $link = db_connect(DB_HOST, DB_USER, DB_PASS, DB_NAME);
 187
 188                                         if (!init_connection($link)) return;
 189
 190                                         // We disable stamp file, since it is of no use in a multiprocess update.
 191                                         // not really, tho for the time being -fox
 192                                         if (!make_stampfile('update_daemon.stamp')) {
 193                                                 print "warning: unable to create stampfile";
 194                                         }
 195
 196                                         // Call to the feed batch update function
 197                                         // or regenerate feedbrowser cache
 198
 199                                         if (rand(0,100) > 30) {
 200                                                 update_daemon_common($link);
 201                                         } else {
 202                                                 $count = update_feedbrowser_cache($link);
 203                                                 _debug("Feedbrowser updated, $count feeds processed.");
 204
 205                                                 purge_orphans($link, true);
 206
 207                                                 $rc = cleanup_tags($link, 14, 50000);
 208
 209                                                 _debug("Cleaned $rc cached tags.");
 210
 211                                                 _debug("Updating linked feeds...");
 212                                                 get_linked_feeds($link);
 213
 214                                         }
 215
 216                                         _debug("Elapsed time: " . (time() - $start_timestamp) . " second(s)");
 217
 218                                         db_close($link);
 219
 220                                         // We are in a fork.
 221                                         // We wait a little before exiting to avoid to be faster than our parent process.
 222                                         sleep(1);
 223
 224                                         unlink(LOCK_DIRECTORY . "/$lock_filename");
 225
 226                                         // We exit in order to avoid fork bombing.
 227                                         exit(0);
 228                                 }
 229
 230                                 // We wait a little time before the next fork, in order to let the first fork
 231                                 // mark the feeds it update :
 232                                 sleep(1);
 233                         }
 234                         $last_checkpoint = time();
 235                 }
 236                 sleep(1);
 237         }
 238
 239 ?>