Add support for inheriting lasso_server objects.

Change configuration to inherit the lasso_server objects when nothing
affecting the lasso_server object changes from the parent configuration
object.

This should speed up processing of requests where you have
request-specific configuration changes, such as access control rules.

git-svn-id: https://modmellon.googlecode.com/svn/trunk/mod_mellon2@130 a716ebb1-153a-0410-b759-cfb97c6a1b53

auth_mellon.h

@@ -212,6 +212,8 @@ typedef struct am_dir_cfg_rec {
     int probe_discovery_timeout;
     apr_hash_t *probe_discovery_idp;
 
+    /* The configuration record we "inherit" the lasso server object from. */
+    struct am_dir_cfg_rec *inherit_server_from;
     /* Mutex to prevent us from creating several lasso server objects. */
     apr_thread_mutex_t *server_mutex;
     /* Cached lasso server object. */

auth_mellon_config.c

@@ -19,6 +19,7 @@
  *
  */
 
+#include <stdbool.h>
 
 #include "auth_mellon.h"
 
@@ -1104,13 +1105,46 @@ void *auth_mellon_dir_config(apr_pool_t *p, char *d)
     dir->sp_org_url = apr_hash_make(p);
 
     apr_thread_mutex_create(&dir->server_mutex, APR_THREAD_MUTEX_DEFAULT, p);
-
+    dir->inherit_server_from = dir;
     dir->server = NULL;
 
     return dir;
 }
 
 
+/* Determine whether this configuration changes anything relevant to the
+ * lasso_server configuration.
+ *
+ * Parameters:
+ *  am_dir_cfg_rec *add_cfg   The new configuration.
+ *
+ * Returns:
+ *  true if we can inherit the lasso_server object, false if not.
+ */
+static bool cfg_can_inherit_lasso_server(const am_dir_cfg_rec *add_cfg)
+{
+    if (add_cfg->endpoint_path != default_endpoint_path)
+        return false;
+
+    if (add_cfg->sp_metadata_file != NULL
+        || add_cfg->sp_private_key_file != NULL
+        || add_cfg->sp_cert_file != NULL)
+        return false;
+    if (add_cfg->idp_metadata->nelts > 0
+        || add_cfg->idp_public_key_file != NULL
+        || add_cfg->idp_ca_file != NULL
+        || add_cfg->idp_ignore != NULL)
+        return false;
+
+    if (apr_hash_count(add_cfg->sp_org_name) > 0
+        || apr_hash_count(add_cfg->sp_org_display_name) > 0
+        || apr_hash_count(add_cfg->sp_org_url) > 0)
+        return false;
+
+    return true;
+}
+
+
 /* This function merges two am_dir_cfg_rec structures.
  * It will try to inherit from the base where possible.
  *
@@ -1264,8 +1298,14 @@ void *auth_mellon_dir_merge(apr_pool_t *p, void *base, void *add)
                        add_cfg->probe_discovery_idp : 
                        base_cfg->probe_discovery_idp);
 
-    apr_thread_mutex_create(&new_cfg->server_mutex,
-                            APR_THREAD_MUTEX_DEFAULT, p);
+
+    if (cfg_can_inherit_lasso_server(add_cfg)) {
+        new_cfg->inherit_server_from = base_cfg->inherit_server_from;
+    } else {
+        apr_thread_mutex_create(&new_cfg->server_mutex,
+                                APR_THREAD_MUTEX_DEFAULT, p);
+        new_cfg->inherit_server_from = new_cfg;
+    }
     new_cfg->server = NULL;
 
     return new_cfg;

auth_mellon_handler.c

@@ -206,14 +206,14 @@ static char *am_generate_metadata(apr_pool_t *p, request_rec *r)
  * This function loads all IdP metadata in a lasso server
  *
  * Parameters:
+ *  am_dir_cfg_rec *cfg  The server configuration.
  *  request_rec *r       The request we received.
  *
  * Returns:
  *  number of loaded providers
  */
-static guint am_server_add_providers(request_rec *r)
+static guint am_server_add_providers(am_dir_cfg_rec *cfg, request_rec *r)
 {
-    am_dir_cfg_rec *cfg = am_get_dir_cfg(r);
     const char *idp_public_key_file;
     apr_size_t index;
 
@@ -276,6 +276,8 @@ static LassoServer *am_get_lasso_server(request_rec *r)
 {
     am_dir_cfg_rec *cfg = am_get_dir_cfg(r);
 
+    cfg = cfg->inherit_server_from;
+
     apr_thread_mutex_lock(cfg->server_mutex);
     if(cfg->server == NULL) {
         if(cfg->sp_metadata_file == NULL) {
@@ -308,7 +310,7 @@ static LassoServer *am_get_lasso_server(request_rec *r)
 	    return NULL;
 	}
 
-        if (am_server_add_providers(r) == 0) {
+        if (am_server_add_providers(cfg, r) == 0) {
 	    ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
 			  "Error adding IdP to lasso server object. Please"
 			  " verify the following configuration directives:"
@@ -2265,6 +2267,8 @@ static int am_handle_metadata(request_rec *r)
     if(server == NULL)
         return HTTP_INTERNAL_SERVER_ERROR;
 
+    cfg = cfg->inherit_server_from;
+
     data = cfg->sp_metadata_file;
     if (data == NULL)
         return HTTP_INTERNAL_SERVER_ERROR;