mirror_corosync/lib/sa-confdb.c
Christine Caulfield 1d2d771f99 This patch adds key_increment and key_decrement calls to the objdb and
confdb subsystems.

This is useful to provide atomic counters (ag handle numbers) for
long-running (though not persistent) connections. It's not currently
possible via confdb to atomically get a new number from objdb due to the
lack of locking. Doing it via increment operations in the IPC thread
provides enough atomicity to make it useful. Fabio has already
identified a use for these calls.

It could also provide some form of basic co-operative locking mechanism
for IPC-using processes (not direct objdb calls).



git-svn-id: http://svn.fedorahosted.org/svn/corosync/trunk@1662 fd59a12c-fef9-0310-b244-a6a79926bd2f
2008-09-03 07:58:08 +00:00

379 lines
8.1 KiB
C

/*
* Copyright (c) 2008 Red Hat, Inc.
*
* All rights reserved.
*
* Author: Christine Caulfield (ccaulfie@redhat.com)
*
* This software licensed under BSD license, the text of which follows:
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* - Neither the name of the MontaVista Software, Inc. nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Provides stand-alone access to data in the corosync object database
* when aisexec is not running.
*/
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <pthread.h>
#include <sys/types.h>
#include <errno.h>
#include <corosync/saAis.h>
#include <corosync/ais_util.h>
#include <corosync/engine/objdb.h>
#include <corosync/engine/config.h>
#include <corosync/engine/logsys.h>
#include <corosync/lcr/lcr_comp.h>
#include <corosync/lcr/lcr_ifact.h>
static struct objdb_iface_ver0 *objdb;
static int num_config_modules;
static struct config_iface_ver0 *config_modules[128];
static int load_objdb()
{
unsigned int objdb_handle;
void *objdb_p;
int res;
/*
* Load the object database interface
*/
res = lcr_ifact_reference (
&objdb_handle,
"objdb",
0,
&objdb_p,
0);
if (res == -1) {
return -1;
}
objdb = (struct objdb_iface_ver0 *)objdb_p;
objdb->objdb_init ();
return SA_AIS_OK;
}
static int load_config()
{
char *config_iface;
char *iface;
int res;
unsigned int config_handle;
unsigned int config_version = 0;
void *config_p;
struct config_iface_ver0 *config;
char *error_string;
/* User's bootstrap config service */
config_iface = getenv("COROSYNC_DEFAULT_CONFIG_IFACE");
if (!config_iface) {
config_iface = "corosync_parser";
}
/* Make a copy so we can deface it with strtok */
config_iface = strdup(config_iface);
iface = strtok(config_iface, ":");
while (iface)
{
res = lcr_ifact_reference (
&config_handle,
iface,
config_version,
&config_p,
0);
config = (struct config_iface_ver0 *)config_p;
if (res == -1) {
return -1;
}
res = config->config_readconfig(objdb, &error_string);
if (res == -1) {
return -1;
}
config_modules[num_config_modules++] = config;
iface = strtok(NULL, ":");
}
if (config_iface)
free(config_iface);
return SA_AIS_OK;
}
/* Needed by objdb when it writes back the configuration */
void main_get_config_modules(struct config_iface_ver0 ***modules, int *num)
{
*modules = config_modules;
*num = num_config_modules;
}
/* Needed by some modules ... */
char *strstr_rs (const char *haystack, const char *needle)
{
char *end_address;
char *new_needle;
new_needle = (char *)strdup (needle);
new_needle[strlen (new_needle) - 1] = '\0';
end_address = strstr (haystack, new_needle);
if (end_address) {
end_address += strlen (new_needle);
end_address = strstr (end_address, needle + strlen (new_needle));
}
if (end_address) {
end_address += 1; /* skip past { or = */
do {
if (*end_address == '\t' || *end_address == ' ') {
end_address++;
} else {
break;
}
} while (*end_address != '\0');
}
free (new_needle);
return (end_address);
}
int confdb_sa_init (void)
{
int res;
res = load_objdb();
if (res != SA_AIS_OK)
return res;
res = load_config();
return res;
}
int confdb_sa_object_create (
unsigned int parent_object_handle,
void *object_name,
int object_name_len,
unsigned int *object_handle)
{
return objdb->object_create(parent_object_handle,
object_handle,
object_name, object_name_len);
}
int confdb_sa_object_destroy (
unsigned int object_handle)
{
return objdb->object_destroy(object_handle);
}
int confdb_sa_object_parent_get (
unsigned int object_handle,
unsigned int *parent_object_handle)
{
return objdb->object_parent_get(object_handle, parent_object_handle);
}
int confdb_sa_key_create (
unsigned int parent_object_handle,
void *key_name,
int key_name_len,
void *value,
int value_len)
{
return objdb->object_key_create(parent_object_handle,
key_name, key_name_len,
value, value_len);
}
int confdb_sa_key_delete (
unsigned int parent_object_handle,
void *key_name,
int key_name_len,
void *value,
int value_len)
{
return objdb->object_key_delete(parent_object_handle,
key_name, key_name_len,
value, value_len);
}
int confdb_sa_key_get (
unsigned int parent_object_handle,
void *key_name,
int key_name_len,
void *value,
int *value_len)
{
int res;
void *kvalue;
res = objdb->object_key_get(parent_object_handle,
key_name, key_name_len,
&kvalue, value_len);
if (!res) {
memcpy(value, kvalue, *value_len);
}
return res;
}
int confdb_sa_key_increment (
unsigned int parent_object_handle,
void *key_name,
int key_name_len,
unsigned int *value)
{
int res;
res = objdb->object_key_increment(parent_object_handle,
key_name, key_name_len,
value);
return res;
}
int confdb_sa_key_decrement (
unsigned int parent_object_handle,
void *key_name,
int key_name_len,
unsigned int *value)
{
int res;
res = objdb->object_key_decrement(parent_object_handle,
key_name, key_name_len,
value);
return res;
}
int confdb_sa_key_replace (
unsigned int parent_object_handle,
void *key_name,
int key_name_len,
void *old_value,
int old_value_len,
void *new_value,
int new_value_len)
{
return objdb->object_key_replace(parent_object_handle,
key_name, key_name_len,
old_value, old_value_len,
new_value, new_value_len);
}
int confdb_sa_write (
unsigned int parent_object_handle,
char *error_text)
{
char *errtext;
int ret;
ret = objdb->object_write_config(&errtext);
if (!ret)
strcpy(error_text, errtext);
return ret;
}
int confdb_sa_reload (
unsigned int parent_object_handle,
int flush,
char *error_text)
{
char *errtext;
int ret;
ret = objdb->object_reload_config(flush, &errtext);
if (!ret)
strcpy(error_text, errtext);
return ret;
}
int confdb_sa_object_find (
unsigned int parent_object_handle,
unsigned int *find_handle,
unsigned int *object_handle,
void *object_name,
int *object_name_len,
int copy_name)
{
int res;
if (!*find_handle) {
objdb->object_find_create(parent_object_handle,
object_name, *object_name_len,
find_handle);
}
res = objdb->object_find_next(*find_handle,
object_handle);
/* Return object name if we were called as _iter */
if (copy_name && !res) {
objdb->object_name_get(*object_handle,
object_name, object_name_len);
}
return res;
}
int confdb_sa_key_iter (
unsigned int parent_object_handle,
unsigned int start_pos,
void *key_name,
int *key_name_len,
void *value,
int *value_len)
{
int res;
void *kname, *kvalue;
res = objdb->object_key_iter_from(parent_object_handle,
start_pos,
&kname, key_name_len,
&kvalue, value_len);
if (!res) {
memcpy(key_name, kname, *key_name_len);
memcpy(value, kvalue, *value_len);
}
return res;
}
int confdb_sa_find_destroy(unsigned int find_handle)
{
return objdb->object_find_destroy(find_handle);
}