Index: simplenews.install
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/simplenews/simplenews.install,v
retrieving revision 1.8.2.34
diff -u -p -r1.8.2.34 simplenews.install
--- simplenews.install	20 Aug 2010 14:44:37 -0000	1.8.2.34
+++ simplenews.install	8 Sep 2010 20:41:00 -0000
@@ -180,6 +180,20 @@ function simplenews_schema() {
         'not null' => TRUE,
         'default' => 0,
       ),
+      'sid' => array(
+        'description' => 'ID from the PHP process handling the batch',
+        'type' => 'varchar',
+        'length' => 255,
+        'not null' => TRUE,
+        'default' => '',
+      ),
+      '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')),
@@ -628,3 +642,15 @@ function simplenews_update_6201() {
   ));
   return $ret;
 }
+
+/**
+ * Add some fields to track which PHP process is handling a batch of messages
+ */
+function simplenews_update_6202() {
+  $ret = array();
+  db_add_field($ret, 'simplenews_mail_spool', 'sid', 
+      array('type' => 'varchar', 'length' => 255, 'not null' => TRUE, 'default' => '', 'description' => 'ID from 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 $ret;
+}
Index: simplenews.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/simplenews/simplenews.module,v
retrieving revision 1.76.2.157
diff -u -p -r1.76.2.157 simplenews.module
--- simplenews.module	7 Sep 2010 02:10:14 -0000	1.76.2.157
+++ simplenews.module	8 Sep 2010 20:41:05 -0000
@@ -1868,7 +1868,23 @@ function simplenews_save_spool($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 process, 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.
+   */
+  $sid = rand();  /* Random number to identify this process */
+  $now = time();
+  $an_hour_ago = $now - (60 * 60);
+  $sql = "UPDATE {simplenews_mail_spool} SET sid='%s', begin_send_timestamp=%d 
+          WHERE status = %d AND ((sid IS NULL OR sid = '') OR begin_send_timestamp < %d) LIMIT %d";
+  $ret = db_query($sql, array($sid, $now, $status, $an_hour_ago, $limit));
+
+  // Get the messages that were claimed for this process
+  $result = db_query("SELECT * FROM {simplenews_mail_spool} s WHERE s.sid = '%s' ORDER BY s.timestamp ASC", array($sid));
   while ($data = db_fetch_array($result)) {
     $message = array();
     foreach ($data as $key => $value) {
@@ -1913,6 +1929,18 @@ function simplenews_count_spool($nid, $v
 }
 
 /**
+ * Count all data in mail spool table that has not been claimed by a send process
+ *
+ * @param string $status email sent status
+ *
+ * @return array Mail message array
+ */
+function simplenews_count_unclaimed_spool($status = SIMPLENEWS_SPOOL_PENDING) {
+  $an_hour_ago = time() - (60 * 60);  
+  return db_result(db_query("SELECT COUNT(*) FROM {simplenews_mail_spool} WHERE status = %d AND ((sid IS NULL OR sid = '') OR begin_send_timestamp < %d)", $status, $an_hour_ago));
+}
+
+/**
  * Remove records from mail spool table.
  *
  * All records with status 'send' and time stamp before the expiration date