1 files changed, 75 insertions, 0 deletions
diff --git a/includes/install.inc b/includes/install.inc
new file mode 100644
index 000000000..6f8a86f65
--- /dev/null
+++ b/includes/install.inc
@@ -0,0 +1,75 @@
+<?php
+// $Id$
+
+define('SCHEMA', 0);
+define('SCHEMA_MIN', 1);
+
+
+// The system module (Drupal core) is currently a special case
+include_once './database/updates.inc';
+
+// Include install files for each module
+foreach (module_list() as $module) {
+  $install_file = './'. drupal_get_path('module', $module) .'/'. $module .'.install';
+  if (is_file($install_file)) {
+    include_once $install_file;
+  }
+}
+
+
+/**
+ * Returns an array of availiable schema versions for a module.
+ *
+ * @param $module
+ *   A module name.
+ * @return
+ *   If the module has updates, an array of available updates. Otherwise,
+ *   FALSE.
+ */
+function drupal_get_schema_versions($module) {
+  if (!($max = module_invoke($module, 'version', SCHEMA))) {
+    return FALSE;
+  }
+  if (!($min = module_invoke($module, 'version', SCHEMA_MIN))) {
+    $min = 1;
+  }
+  return range($min, $max);
+}
+
+/**
+ * Returns the currently installed schema version for a module.
+ *
+ * @param $module
+ *   A module name.
+ * @return
+ *   The currently installed schema version.
+ */
+function drupal_get_installed_schema_version($module, $reset = FALSE) {
+  static $versions;
+
+  if ($reset) {
+    unset($versions);
+  }
+
+  if (!$versions) {
+    $versions = array();
+    $result = db_query("SELECT name, schema_version FROM {system} WHERE type = 'module'");
+    while ($row = db_fetch_object($result)) {
+      $versions[$row->name] = $row->schema_version;
+    }
+  }
+
+  return $versions[$module];
+}
+
+/**
+ * Update the installed version information for a module.
+ *
+ * @param $module
+ *   A module name.
+ * @param $version
+ *   The new schema version.
+ */
+function drupal_set_installed_schema_version($module, $version) {
+  db_query("UPDATE {system} SET schema_version = %d WHERE name = '%s'", $version, $module);
+}