update_daemon2.php

   1 #!/usr/bin/env php
   2 <?php
   3         set_include_path(dirname(__FILE__) ."/include" . PATH_SEPARATOR .
   4                 get_include_path());
   5
   6         declare(ticks = 1);
   7         chdir(dirname(__FILE__));
   8
   9         define('DISABLE_SESSIONS', true);
  10
  11         require_once "version.php";
  12         require_once "autoload.php";
  13         require_once "functions.php";
  14         require_once "config.php";
  15         require_once "rssfuncs.php";
  16
  17         // defaults
  18         define_default('PURGE_INTERVAL', 3600); // seconds
  19         define_default('MAX_CHILD_RUNTIME', 1800); // seconds
  20         define_default('MAX_JOBS', 2);
  21         define_default('SPAWN_INTERVAL', DAEMON_SLEEP_INTERVAL); // seconds
  22
  23         require_once "sanity_check.php";
  24         require_once "db.php";
  25         require_once "db-prefs.php";
  26
  27         if (!function_exists('pcntl_fork')) {
  28                 die("error: This script requires PHP compiled with PCNTL module.\n");
  29         }
  30
  31         $options = getopt("");
  32
  33         if (!is_array($options)) {
  34                 die("error: getopt() failed. ".
  35                         "Most probably you are using PHP CGI to run this script ".
  36                         "instead of required PHP CLI. Check tt-rss wiki page on updating feeds for ".
  37                         "additional information.\n");
  38         }
  39
  40
  41         $master_handlers_installed = false;
  42
  43         $children = array();
  44         $ctimes = array();
  45
  46         $last_checkpoint = -1;
  47
  48         function reap_children() {
  49                 global $children;
  50                 global $ctimes;
  51
  52                 $tmp = array();
  53
  54                 foreach ($children as $pid) {
  55                         if (pcntl_waitpid($pid, $status, WNOHANG) != $pid) {
  56
  57                                 if (file_is_locked("update_daemon-$pid.lock")) {
  58                                         array_push($tmp, $pid);
  59                                 } else {
  60                                         _debug("[reap_children] child $pid seems active but lockfile is unlocked.");
  61                                         unset($ctimes[$pid]);
  62
  63                                 }
  64                         } else {
  65                                 _debug("[reap_children] child $pid reaped.");
  66                                 unset($ctimes[$pid]);
  67                         }
  68                 }
  69
  70                 $children = $tmp;
  71
  72                 return count($tmp);
  73         }
  74
  75         function check_ctimes() {
  76                 global $ctimes;
  77
  78                 foreach (array_keys($ctimes) as $pid) {
  79                         $started = $ctimes[$pid];
  80
  81                         if (time() - $started > MAX_CHILD_RUNTIME) {
  82                                 _debug("[MASTER] child process $pid seems to be stuck, aborting...");
  83                                 posix_kill($pid, SIGKILL);
  84                         }
  85                 }
  86         }
  87
  88         function sigchld_handler($signal) {
  89                 $running_jobs = reap_children();
  90
  91                 _debug("[SIGCHLD] jobs left: $running_jobs");
  92
  93                 pcntl_waitpid(-1, $status, WNOHANG);
  94         }
  95
  96         function shutdown($caller_pid) {
  97                 if ($caller_pid == posix_getpid()) {
  98                         if (file_exists(LOCK_DIRECTORY . "/update_daemon.lock")) {
  99                                 _debug("removing lockfile (master)...");
 100                                 unlink(LOCK_DIRECTORY . "/update_daemon.lock");
 101                         }
 102                 }
 103         }
 104
 105         function task_shutdown() {
 106                 $pid = posix_getpid();
 107
 108                 if (file_exists(LOCK_DIRECTORY . "/update_daemon-$pid.lock")) {
 109                         _debug("removing lockfile ($pid)...");
 110                         unlink(LOCK_DIRECTORY . "/update_daemon-$pid.lock");
 111                 }
 112         }
 113
 114         function sigint_handler() {
 115                 _debug("[MASTER] SIG_INT received.\n");
 116                 shutdown(posix_getpid());
 117                 die;
 118         }
 119
 120         function task_sigint_handler() {
 121                 _debug("[TASK] SIG_INT received.\n");
 122                 task_shutdown();
 123                 die;
 124         }
 125
 126         pcntl_signal(SIGCHLD, 'sigchld_handler');
 127
 128         $longopts = array("log:",
 129                         "tasks:",
 130                         "interval:",
 131                         "quiet",
 132                         "help");
 133
 134         $options = getopt("", $longopts);
 135
 136         if (isset($options["help"]) ) {
 137                 print "Tiny Tiny RSS update daemon.\n\n";
 138                 print "Options:\n";
 139                 print "  --log FILE           - log messages to FILE\n";
 140                 print "  --tasks N            - amount of update tasks to spawn\n";
 141                 print "                         default: " . MAX_JOBS . "\n";
 142                 print "  --interval N         - task spawn interval\n";
 143                 print "                         default: " . SPAWN_INTERVAL . " seconds.\n";
 144                 print "  --quiet              - don't output messages to stdout\n";
 145                 return;
 146         }
 147
 148         define('QUIET', isset($options['quiet']));
 149
 150         if (isset($options["tasks"])) {
 151                 _debug("Set to spawn " . $options["tasks"] . " children.");
 152                 $max_jobs = $options["tasks"];
 153         } else {
 154                 $max_jobs = MAX_JOBS;
 155         }
 156
 157         if (isset($options["interval"])) {
 158                 _debug("Spawn interval: " . $options["interval"] . " seconds.");
 159                 $spawn_interval = $options["interval"];
 160         } else {
 161                 $spawn_interval = SPAWN_INTERVAL;
 162         }
 163
 164         if (isset($options["log"])) {
 165                 _debug("Logging to " . $options["log"]);
 166                 define('LOGFILE', $options["log"]);
 167         }
 168
 169         if (file_is_locked("update_daemon.lock")) {
 170                 die("error: Can't create lockfile. ".
 171                         "Maybe another daemon is already running.\n");
 172         }
 173
 174         // Try to lock a file in order to avoid concurrent update.
 175         $lock_handle = make_lockfile("update_daemon.lock");
 176
 177         if (!$lock_handle) {
 178                 die("error: Can't create lockfile. ".
 179                         "Maybe another daemon is already running.\n");
 180         }
 181
 182         $schema_version = get_schema_version();
 183
 184         if ($schema_version != SCHEMA_VERSION) {
 185                 die("Schema version is wrong, please upgrade the database.\n");
 186         }
 187
 188         // Protip: children close shared database handle when terminating, it's a bad idea to
 189         // do database stuff on main process from now on.
 190
 191         while (true) {
 192
 193                 // Since sleep is interupted by SIGCHLD, we need another way to
 194                 // respect the spawn interval
 195                 $next_spawn = $last_checkpoint + $spawn_interval - time();
 196
 197                 if ($next_spawn % 60 == 0) {
 198                         $running_jobs = count($children);
 199                         _debug("[MASTER] active jobs: $running_jobs, next spawn at $next_spawn sec.");
 200                 }
 201
 202                 if ($last_checkpoint + $spawn_interval < time()) {
 203                         check_ctimes();
 204                         reap_children();
 205
 206                         for ($j = count($children); $j < $max_jobs; $j++) {
 207                                 $pid = pcntl_fork();
 208                                 if ($pid == -1) {
 209                                         die("fork failed!\n");
 210                                 } else if ($pid) {
 211
 212                                         if (!$master_handlers_installed) {
 213                                                 _debug("[MASTER] installing shutdown handlers");
 214                                                 pcntl_signal(SIGINT, 'sigint_handler');
 215                                                 pcntl_signal(SIGTERM, 'sigint_handler');
 216                                                 register_shutdown_function('shutdown', posix_getpid());
 217                                                 $master_handlers_installed = true;
 218                                         }
 219
 220                                         _debug("[MASTER] spawned client $j [PID:$pid]...");
 221                                         array_push($children, $pid);
 222                                         $ctimes[$pid] = time();
 223                                 } else {
 224                                         pcntl_signal(SIGCHLD, SIG_IGN);
 225                                         pcntl_signal(SIGINT, 'task_sigint_handler');
 226
 227                                         register_shutdown_function('task_shutdown');
 228
 229                                         $quiet = (isset($options["quiet"])) ? "--quiet" : "";
 230                                         $log = function_exists("flock") && isset($options['log']) ? '--log '.$options['log'] : '';
 231
 232                                         $my_pid = posix_getpid();
 233
 234                                         passthru(PHP_EXECUTABLE . " update.php --daemon-loop $quiet $log --task $j --pidlock $my_pid");
 235
 236                                         sleep(1);
 237
 238                                         // We exit in order to avoid fork bombing.
 239                                         exit(0);
 240                                 }
 241                         }
 242                         $last_checkpoint = time();
 243                 }
 244                 sleep(1);
 245         }
 246
 247 ?>