? simplenews-361071-11.patch
Index: simplenews.install
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/simplenews/simplenews.install,v
retrieving revision 1.8.2.33
diff -u -p -r1.8.2.33 simplenews.install
--- simplenews.install	21 May 2010 15:37:41 -0000	1.8.2.33
+++ simplenews.install	8 Aug 2010 19:49:36 -0000
@@ -180,6 +180,20 @@ function simplenews_schema() {
         'not null' => TRUE,
         'default' => 0,
       ),
+      'pid' => array(
+        'description' => 'ID of the PHP process handling the batch',
+        'type' => 'int',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+        'default' => 0,
+      ),
+      'begin_send_timestamp' => array(
+        'description' => 'Time the batch began processing',
+        'type' => 'int',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+        'default' => 0,
+      ),
     ),
     'primary key' => array('msid'),
     'indexes' => array('tid' => array('tid'), 'status' => array('status')),
@@ -635,3 +649,15 @@ function simplenews_update_6011() {
   ));
   return $ret;
 }
+
+/**
+ * Add some fields to track which PHP process is handling a batch of messages
+ */
+function simplenews_update_6201() {
+  $ret = array();
+  db_add_field($ret, 'simplenews_mail_spool', 'pid', 
+      array('type' => 'int', 'not null' => TRUE, 'default' => 0, 'description' => 'ID of the PHP process handling the batch'));
+  db_add_field($ret, 'simplenews_mail_spool', 'begin_send_timestamp', 
+      array('type' => 'int', 'not null' => TRUE, 'default' => 0, 'description' => 'Time the batch began processing'));
+  return $ret;
+}
Index: simplenews.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/simplenews/simplenews.module,v
retrieving revision 1.76.2.156
diff -u -p -r1.76.2.156 simplenews.module
--- simplenews.module	19 May 2010 14:01:22 -0000	1.76.2.156
+++ simplenews.module	8 Aug 2010 19:49:36 -0000
@@ -1867,7 +1867,23 @@ function simplenews_save_spool($message)
 function simplenews_get_spool($status, $nid = NULL, $vid = NULL, $limit = 999999) {
   $messages = array();
 
-  $result = db_query_range("SELECT * FROM {simplenews_mail_spool} s WHERE s.status = %d ORDER BY s.timestamp ASC", $status, 0, $limit);
+  /**
+   * Choose the messages that will be sent by this process
+   * This query will mark pending messages as belonging to this PHP process ID, and includes the current timestamp 
+   * as the begin time. This way, no other processes will try to send the same messages, which could result in 
+   * duplicates messages sent (this was a problem with poormanscron). 
+   * The query will also claim any messages that had already been claimed by another process, but were started over 
+   * an hour ago. This way, if a process fails before completing its batch, another process will take care of it later.
+   */
+  $pid = getmypid();
+  $now = time();
+  $an_hour_ago = $now - (60 * 60);
+  $sql = "UPDATE {simplenews_mail_spool} SET pid=%d, begin_send_timestamp=%d 
+          WHERE status = %d AND (pid = 0 OR begin_send_timestamp < %d) LIMIT %d";
+  $ret = db_query($sql, array($pid, $now, $status, $an_hour_ago, $limit));
+
+  // Get the messages that were claimed for this process
+  $result = db_query("SELECT * FROM {simplenews_mail_spool} s WHERE s.pid = %d ORDER BY s.timestamp ASC", array($pid));
   while ($data = db_fetch_array($result)) {
     $message = array();
     foreach ($data as $key => $value) {