update_daemon2.php

   1 #!/usr/bin/php
   2 <?php
   3         set_include_path(get_include_path() . PATH_SEPARATOR .
   4                 dirname(__FILE__) . "/include");
   5
   6         // This is an experimental multiprocess update daemon.
   7         // Some configurable variable may be found below.
   8
   9         declare(ticks = 1);
  10         chdir(dirname(__FILE__));
  11
  12         define('DISABLE_SESSIONS', true);
  13
  14         require_once "version.php";
  15
  16         if (strpos(VERSION, ".99") !== false || getenv('DAEMON_XDEBUG')) {
  17                 define('DAEMON_EXTENDED_DEBUG', true);
  18         }
  19
  20         define('PURGE_INTERVAL', 3600); // seconds
  21         define('MAX_CHILD_RUNTIME', 600); // seconds
  22
  23         require_once "sanity_check.php";
  24         require_once "config.php";
  25
  26         define('MAX_JOBS', 2);
  27         define('SPAWN_INTERVAL', DAEMON_SLEEP_INTERVAL);
  28
  29         if (!function_exists('pcntl_fork')) {
  30                 die("error: This script requires PHP compiled with PCNTL module.\n");
  31         }
  32
  33         require_once "db.php";
  34         require_once "db-prefs.php";
  35         require_once "functions.php";
  36         require_once "rssfuncs.php";
  37         require_once "lib/magpierss/rss_fetch.inc";
  38
  39         $children = array();
  40         $ctimes = array();
  41
  42         $last_checkpoint = -1;
  43
  44         function reap_children() {
  45                 global $children;
  46                 global $ctimes;
  47
  48                 $tmp = array();
  49
  50                 foreach ($children as $pid) {
  51                         if (pcntl_waitpid($pid, $status, WNOHANG) != $pid) {
  52
  53                                 if (file_is_locked("update_daemon-$pid.lock")) {
  54                                         array_push($tmp, $pid);
  55                                 } else {
  56                                         _debug("[reap_children] child $pid seems active but lockfile is unlocked.");
  57                                 }
  58                         } else {
  59                                 _debug("[reap_children] child $pid reaped.");
  60                                 unset($ctimes[$pid]);
  61                         }
  62                 }
  63
  64                 $children = $tmp;
  65
  66                 return count($tmp);
  67         }
  68
  69         function check_ctimes() {
  70                 global $ctimes;
  71
  72                 foreach (array_keys($ctimes) as $pid) {
  73                         $started = $ctimes[$pid];
  74
  75                         if (time() - $started > MAX_CHILD_RUNTIME) {
  76                                 _debug("[MASTER] child process $pid seems to be stuck, aborting...");
  77                                 posix_kill($pid, SIGKILL);
  78                         }
  79                 }
  80         }
  81
  82         function sigchld_handler($signal) {
  83                 $running_jobs = reap_children();
  84
  85                 _debug("[SIGCHLD] jobs left: $running_jobs");
  86
  87                 pcntl_waitpid(-1, $status, WNOHANG);
  88         }
  89
  90         function shutdown() {
  91                 if (file_exists(LOCK_DIRECTORY . "/update_daemon.lock"))
  92                         unlink(LOCK_DIRECTORY . "/update_daemon.lock");
  93         }
  94
  95         function task_shutdown() {
  96                 $pid = posix_getpid();
  97
  98                 if (file_exists(LOCK_DIRECTORY . "/update_daemon-$pid.lock"))
  99                         unlink(LOCK_DIRECTORY . "/update_daemon-$pid.lock");
 100         }
 101
 102         function sigint_handler() {
 103                 shutdown();
 104                 die("[SIGINT] removing lockfile and exiting.\n");
 105         }
 106
 107         function task_sigint_handler() {
 108                 task_shutdown();
 109                 die("[SIGINT] removing lockfile and exiting.\n");
 110         }
 111
 112         pcntl_signal(SIGCHLD, 'sigchld_handler');
 113
 114         if (file_is_locked("update_daemon.lock")) {
 115                 die("error: Can't create lockfile. ".
 116                         "Maybe another daemon is already running.\n");
 117         }
 118
 119         if (!pcntl_fork()) {
 120                 pcntl_signal(SIGINT, 'sigint_handler');
 121                 register_shutdown_function('shutdown');
 122
 123                 // Try to lock a file in order to avoid concurrent update.
 124                 $lock_handle = make_lockfile("update_daemon.lock");
 125
 126                 if (!$lock_handle) {
 127                         die("error: Can't create lockfile. ".
 128                                 "Maybe another daemon is already running.\n");
 129                 }
 130
 131                 while (true) { sleep(100); }
 132         }
 133
 134         // Testing database connection.
 135         // It is unnecessary to start the fork loop if database is not ok.
 136         $link = db_connect(DB_HOST, DB_USER, DB_PASS, DB_NAME);
 137
 138         if (!init_connection($link)) return;
 139
 140         db_close($link);
 141
 142         while (true) {
 143
 144                 // Since sleep is interupted by SIGCHLD, we need another way to
 145                 // respect the SPAWN_INTERVAL
 146                 $next_spawn = $last_checkpoint + SPAWN_INTERVAL - time();
 147
 148                 if ($next_spawn % 10 == 0) {
 149                         $running_jobs = count($children);
 150                         _debug("[MASTER] active jobs: $running_jobs, next spawn at $next_spawn sec.");
 151                 }
 152
 153                 if ($last_checkpoint + SPAWN_INTERVAL < time()) {
 154
 155                         check_ctimes();
 156                         reap_children();
 157
 158                         for ($j = count($children); $j < MAX_JOBS; $j++) {
 159                                 $pid = pcntl_fork();
 160                                 if ($pid == -1) {
 161                                         die("fork failed!\n");
 162                                 } else if ($pid) {
 163                                         _debug("[MASTER] spawned client $j [PID:$pid]...");
 164                                         array_push($children, $pid);
 165                                         $ctimes[$pid] = time();
 166                                 } else {
 167                                         pcntl_signal(SIGCHLD, SIG_IGN);
 168                                         pcntl_signal(SIGINT, 'task_sigint_handler');
 169
 170                                         register_shutdown_function('task_shutdown');
 171
 172                                         $my_pid = posix_getpid();
 173                                         $lock_filename = "update_daemon-$my_pid.lock";
 174
 175                                         $lock_handle = make_lockfile($lock_filename);
 176
 177                                         if (!$lock_handle) {
 178                                                 die("error: Can't create lockfile ($lock_filename). ".
 179                                                 "Maybe another daemon is already running.\n");
 180                                         }
 181
 182                                         // ****** Updating RSS code *******
 183                                         // Only run in fork process.
 184
 185                                         $start_timestamp = time();
 186
 187                                         $link = db_connect(DB_HOST, DB_USER, DB_PASS, DB_NAME);
 188
 189                                         if (!init_connection($link)) return;
 190
 191                                         // We disable stamp file, since it is of no use in a multiprocess update.
 192                                         // not really, tho for the time being -fox
 193                                         if (!make_stampfile('update_daemon.stamp')) {
 194                                                 print "warning: unable to create stampfile";
 195                                         }
 196
 197                                         // Call to the feed batch update function
 198                                         // or regenerate feedbrowser cache
 199
 200                                         if (rand(0,100) > 30) {
 201                                                 update_daemon_common($link);
 202                                         } else {
 203                                                 $count = update_feedbrowser_cache($link);
 204                                                 _debug("Feedbrowser updated, $count feeds processed.");
 205
 206                                                 purge_orphans($link, true);
 207
 208                                                 $rc = cleanup_tags($link, 14, 50000);
 209
 210                                                 _debug("Cleaned $rc cached tags.");
 211
 212                                                 _debug("Updating linked feeds...");
 213                                                 get_linked_feeds($link);
 214
 215                                         }
 216
 217                                         _debug("Elapsed time: " . (time() - $start_timestamp) . " second(s)");
 218
 219                                         db_close($link);
 220
 221                                         // We are in a fork.
 222                                         // We wait a little before exiting to avoid to be faster than our parent process.
 223                                         sleep(1);
 224
 225                                         unlink(LOCK_DIRECTORY . "/$lock_filename");
 226
 227                                         // We exit in order to avoid fork bombing.
 228                                         exit(0);
 229                                 }
 230
 231                                 // We wait a little time before the next fork, in order to let the first fork
 232                                 // mark the feeds it update :
 233                                 sleep(1);
 234                         }
 235                         $last_checkpoint = time();
 236                 }
 237                 sleep(1);
 238         }
 239
 240 ?>