Provide ap_set_retained_data()/ap_get_retained_data() for preservation

of module state across unload/load.

The existing idiom used by modules to associate userdata with pglobal
doesn't work in the earliest phases of module execution.

(This does expose pglobal as an implementation detail, but it would be great
to unexpose it if at all possible (but modules already have access to pglobal
at almost all stages of execution anyway).)

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@758173 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/CHANGES b/CHANGES
index e16d0be1b1f9a0b6f02f10f38477d86d479e4cb2..e8c8e8175399c367e6652cad288c1f678f954f8c 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -2,6 +2,9 @@
 
 Changes with Apache 2.3.3
 
+  *) Provide ap_set_retained_data()/ap_get_retained_data() for preservation
+     of module state across unload/load.  [Jeff Trawick]
+
   *) mod_substitute: Fix a memory leak. PR 44948
      [Dan Poirier <poirier pobox.com>]
 

diff --git a/include/ap_mmn.h b/include/ap_mmn.h
index 8c003d28bbc32802b3e0baf7ca5dd09b19192d82..aaaff2e456c5a10cf02a33864661f80caecedde6 100644 (file)
--- a/include/ap_mmn.h
+++ b/include/ap_mmn.h
@@ -189,6 +189,7 @@
  * 20090130.0 (2.3.2-dev)  Add ap_ prefix to unixd_setup_child().
  * 20090131.0 (2.3.2-dev)  Remove ap_default_type(), disable DefaultType
  * 20090208.0 (2.3.2-dev)  Add conn_rec::current_thread.
+ * 20090208.1 (2.3.3-dev)  Add ap_set_retained_data()/ap_get_retained_data()
  */
 
 #define MODULE_MAGIC_COOKIE 0x41503234UL /* "AP24" */
@@ -196,7 +197,7 @@
 #ifndef MODULE_MAGIC_NUMBER_MAJOR
 #define MODULE_MAGIC_NUMBER_MAJOR 20090208
 #endif
-#define MODULE_MAGIC_NUMBER_MINOR 0                     /* 0...n */
+#define MODULE_MAGIC_NUMBER_MINOR 1                     /* 0...n */
 
 /**
  * Determine if the server's current MODULE_MAGIC_NUMBER is at least a

diff --git a/include/http_config.h b/include/http_config.h
index cba626ea5883d46ff7d6bb27e712c58682d2e175..6ad90870461fbaf6407f3e0a62440773c12bd455 100644 (file)
--- a/include/http_config.h
+++ b/include/http_config.h
@@ -915,6 +915,21 @@ AP_DECLARE(int) ap_process_config_tree(server_rec *s,
                                        apr_pool_t *p,
                                        apr_pool_t *ptemp);
 
+/**
+ * Store data which will be retained across unload/load of modules
+ * @param key The unique key associated with this module's retained data
+ * @param Size in bytes of the retained data (to be allocated)
+ * @return Address of new retained data structure, initially cleared
+ */
+AP_DECLARE(void *) ap_set_retained_data(const char *key, apr_size_t size);
+
+/**
+ * Retrieve data which was stored by ap_set_retained_data()
+ * @param key The unique key associated with this module's retained data
+ * @return Address of previously retained data structure, or NULL if not yet saved
+ */
+AP_DECLARE(void *) ap_get_retained_data(const char *key);
+    
 /* Module-method dispatchers, also for http_request.c */
 /**
  * Run the handler phase of each module until a module accepts the

diff --git a/include/http_main.h b/include/http_main.h
index 545ba5ac13b602b3b5b4589a924bdb4143db9020..dc0a0de61b415464a4b4be20676fc7fe0823807f 100644 (file)
--- a/include/http_main.h
+++ b/include/http_main.h
@@ -45,6 +45,8 @@ AP_DECLARE_DATA extern const char *ap_server_argv0;
 AP_DECLARE_DATA extern const char *ap_server_root;
 /** The global server's server_rec */
 AP_DECLARE_DATA extern server_rec *ap_server_conf;
+/** global pool, for access prior to creation of server_rec */
+AP_DECLARE_DATA extern apr_pool_t *ap_pglobal;
 
 /* for -C, -c and -D switches */
 /** An array of all -C directives.  These are processed before the server's

diff --git a/server/config.c b/server/config.c
index fc2cb31dfada2945e6d68af1f398df9430e1105f..f87c44c384248bc069987bbd75f52c8f61f0cb6f 100644 (file)
--- a/server/config.c
+++ b/server/config.c
@@ -53,6 +53,7 @@
 AP_DECLARE_DATA const char *ap_server_argv0 = NULL;
 AP_DECLARE_DATA const char *ap_server_root = NULL;
 AP_DECLARE_DATA server_rec *ap_server_conf = NULL;
+AP_DECLARE_DATA apr_pool_t *ap_pglobal = NULL;
 
 AP_DECLARE_DATA apr_array_header_t *ap_server_pre_read_config = NULL;
 AP_DECLARE_DATA apr_array_header_t *ap_server_post_read_config = NULL;
@@ -2193,3 +2194,19 @@ AP_DECLARE(void) ap_show_modules(void)
         printf("  %s\n", ap_loaded_modules[n]->name);
 }
 
+AP_DECLARE(void *) ap_get_retained_data(const char *key)
+{
+    void *retained;
+
+    apr_pool_userdata_get((void *)&retained, key, ap_pglobal);
+    return retained;
+}
+
+AP_DECLARE(void *) ap_set_retained_data(const char *key, apr_size_t size)
+{
+    void *retained;
+
+    retained = apr_pcalloc(ap_pglobal, size);
+    apr_pool_userdata_set((const void *)retained, key, apr_pool_cleanup_null, ap_pglobal);
+    return retained;
+}

diff --git a/server/main.c b/server/main.c
index 48a5c234f1dbe9ef4661f908eecec98cb0c7731f..5dff38339a02443c5682116b83a9f1d80209c40f 100644 (file)
--- a/server/main.c
+++ b/server/main.c
@@ -471,7 +471,6 @@ int main(int argc, const char * const argv[])
     const char *temp_error_log = NULL;
     const char *error;
     process_rec *process;
-    apr_pool_t *pglobal;
     apr_pool_t *pconf;
     apr_pool_t *plog; /* Pool of log streams, reset _after_ each read of conf */
     apr_pool_t *ptemp; /* Pool for temporary config stuff, reset often */
@@ -485,7 +484,7 @@ int main(int argc, const char * const argv[])
     AP_MONCONTROL(0); /* turn off profiling of startup */
 
     process = init_process(&argc, &argv);
-    pglobal = process->pool;
+    ap_pglobal = process->pool;
     pconf = process->pconf;
     ap_server_argv0 = process->short_name;
 
@@ -494,15 +493,15 @@ int main(int argc, const char * const argv[])
     apr_pool_abort_set(abort_on_oom, apr_pool_parent_get(process->pool));
 
 #if APR_CHARSET_EBCDIC
-    if (ap_init_ebcdic(pglobal) != APR_SUCCESS) {
+    if (ap_init_ebcdic(ap_pglobal) != APR_SUCCESS) {
         destroy_and_exit_process(process, 1);
     }
 #endif
-    if (ap_expr_init(pglobal) != APR_SUCCESS) {
+    if (ap_expr_init(ap_pglobal) != APR_SUCCESS) {
         destroy_and_exit_process(process, 1);
     }
 
-    apr_pool_create(&pcommands, pglobal);
+    apr_pool_create(&pcommands, ap_pglobal);
     apr_pool_tag(pcommands, "pcommands");
     ap_server_pre_read_config  = apr_array_make(pcommands, 1, sizeof(char *));
     ap_server_post_read_config = apr_array_make(pcommands, 1, sizeof(char *));
@@ -639,7 +638,7 @@ int main(int argc, const char * const argv[])
         usage(process);
     }
 
-    apr_pool_create(&plog, pglobal);
+    apr_pool_create(&plog, ap_pglobal);
     apr_pool_tag(plog, "plog");
     apr_pool_create(&ptemp, pconf);
     apr_pool_tag(ptemp, "ptemp");