Commit 8b0dada0 authored by Bradley Nicholes's avatar Bradley Nicholes
Browse files

Switch the caching mutexes from reader/writer thread locks to global mutexes... 

Switch the caching mutexes from reader/writer thread locks to global mutexes to allow for protection across processes rather than just across threads.

Reviewed by: bnicholes, minfrin, jjclar


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/APACHE_2_0_BRANCH@104493 13f79535-47bb-0310-9956-ffa450edef68
parent 2a0e25b2

include/util_ldap.h

+2 −1
Changes for include/util_ldap.h: 2 added lines, 1 removed line.
Original line number Diff line number Diff line
@@ -102,8 +102,8 @@ typedef struct util_ldap_state_t { 
    apr_pool_t *pool;           /* pool from which this state is allocated */

#if APR_HAS_THREADS

    apr_thread_mutex_t *mutex;          /* mutex lock for the connection list */

    apr_thread_rwlock_t *util_ldap_cache_lock;

#endif

    apr_global_mutex_t *util_ldap_cache_lock;



    apr_size_t cache_bytes;     /* Size (in bytes) of shared memory cache */

    char *cache_file;           /* filename for shm */
@@ -124,6 +124,7 @@ typedef struct util_ldap_state_t { 


    /* cache ald */

    void *util_ldap_cache;

    char *lock_file;           /* filename for shm lock mutex */



} util_ldap_state_t;

modules/experimental/util_ldap.c

+76 −24
Changes for modules/experimental/util_ldap.c: 76 added lines, 24 removed lines.
Original line number Diff line number Diff line
@@ -88,6 +88,11 @@ void *util_ldap_create_config(apr_pool_t *p, server_rec *s); 
                          "\"http://www.w3.org/TR/REC-html40/frameset.dtd\">\n"

#endif



#define LDAP_CACHE_LOCK() \

    apr_global_mutex_lock(st->util_ldap_cache_lock)

#define LDAP_CACHE_UNLOCK() \

    apr_global_mutex_unlock(st->util_ldap_cache_lock)





static void util_ldap_strdup (char **str, const char *newstr)

{
@@ -498,11 +503,8 @@ LDAP_DECLARE(int) util_ldap_cache_comparedn(request_rec *r, util_ldap_connection 


    util_ldap_state_t *st =  (util_ldap_state_t *)ap_get_module_config(r->server->module_config, &ldap_module);



    /* read lock this function */

    LDAP_CACHE_LOCK_CREATE(st->pool);



    /* get cache entry (or create one) */

    LDAP_CACHE_WRLOCK();

    LDAP_CACHE_LOCK();



    curnode.url = url;

    curl = util_ald_cache_fetch(st->util_ldap_cache, &curnode);
@@ -526,7 +528,7 @@ LDAP_DECLARE(int) util_ldap_cache_comparedn(request_rec *r, util_ldap_connection 


    if (curl) {

        /* no - it's a server side compare */

        LDAP_CACHE_RDLOCK();

        LDAP_CACHE_LOCK();

    

        /* is it in the compare cache? */

        newnode.reqdn = (char *)reqdn;
@@ -581,7 +583,7 @@ start_over: 
    else {

        if (curl) {

            /* compare successful - add to the compare cache */

            LDAP_CACHE_WRLOCK();

            LDAP_CACHE_LOCK();

            newnode.reqdn = (char *)reqdn;

            newnode.dn = (char *)dn;
@@ -625,11 +627,8 @@ LDAP_DECLARE(int) util_ldap_cache_compare(request_rec *r, util_ldap_connection_t 
        (util_ldap_state_t *)ap_get_module_config(r->server->module_config,

        &ldap_module);



    /* read lock this function */

    LDAP_CACHE_LOCK_CREATE(st->pool);



    /* get cache entry (or create one) */

    LDAP_CACHE_WRLOCK();

    LDAP_CACHE_LOCK();

    curnode.url = url;

    curl = util_ald_cache_fetch(st->util_ldap_cache, &curnode);

    if (curl == NULL) {
@@ -639,7 +638,7 @@ LDAP_DECLARE(int) util_ldap_cache_compare(request_rec *r, util_ldap_connection_t 


    if (curl) {

        /* make a comparison to the cache */

        LDAP_CACHE_RDLOCK();

        LDAP_CACHE_LOCK();

        curtime = apr_time_now();

    

        the_compare_node.dn = (char *)dn;
@@ -705,7 +704,7 @@ start_over: 
        (LDAP_NO_SUCH_ATTRIBUTE == result)) {

        if (curl) {

            /* compare completed; caching result */

            LDAP_CACHE_WRLOCK();

            LDAP_CACHE_LOCK();

            the_compare_node.lastcompare = curtime;

            the_compare_node.result = result;
@@ -762,11 +761,8 @@ LDAP_DECLARE(int) util_ldap_cache_checkuserid(request_rec *r, util_ldap_connecti 
        (util_ldap_state_t *)ap_get_module_config(r->server->module_config,

        &ldap_module);



    /* read lock this function */

    LDAP_CACHE_LOCK_CREATE(st->pool);



    /* Get the cache node for this url */

    LDAP_CACHE_WRLOCK();

    LDAP_CACHE_LOCK();

    curnode.url = url;

    curl = (util_url_node_t *)util_ald_cache_fetch(st->util_ldap_cache, &curnode);

    if (curl == NULL) {
@@ -775,7 +771,7 @@ LDAP_DECLARE(int) util_ldap_cache_checkuserid(request_rec *r, util_ldap_connecti 
    LDAP_CACHE_UNLOCK();



    if (curl) {

        LDAP_CACHE_RDLOCK();

        LDAP_CACHE_LOCK();

        the_search_node.username = filter;

        search_nodep = util_ald_cache_fetch(curl->search_cache, &the_search_node);

        if (search_nodep != NULL && search_nodep->bindpw) {
@@ -934,7 +930,7 @@ start_over: 
     * Add the new username to the search cache.

     */

    if (curl) {

        LDAP_CACHE_WRLOCK();

        LDAP_CACHE_LOCK();

        the_search_node.username = filter;

        the_search_node.dn = *binddn;

        the_search_node.bindpw = bindpw;
@@ -1172,14 +1168,36 @@ static int util_ldap_post_config(apr_pool_t *p, apr_pool_t *plog, 
    int rc = LDAP_SUCCESS;

    apr_status_t result;

    char buf[MAX_STRING_LEN];

    server_rec *s_vhost;

    util_ldap_state_t *st_vhost;



    util_ldap_state_t *st =

        (util_ldap_state_t *)ap_get_module_config(s->module_config, &ldap_module);



    void *data;

    const char *userdata_key = "util_ldap_init";



    /* util_ldap_post_config() will be called twice. Don't bother

     * going through all of the initialization on the first call

     * because it will just be thrown away.*/

    apr_pool_userdata_get(&data, userdata_key, s->process->pool);

    if (!data) {

        apr_pool_userdata_set((const void *)1, userdata_key,

                               apr_pool_cleanup_null, s->process->pool);



#if APR_HAS_SHARED_MEMORY

    server_rec *s_vhost;

    util_ldap_state_t *st_vhost;

        /* If the cache file already exists then delete it.  Otherwise we are

         * going to run into problems creating the shared memory. */

        if (st->cache_file) {

            char *lck_file = apr_pstrcat (st->pool, st->cache_file, ".lck", NULL);

            apr_file_remove(st->cache_file, ptemp);

            apr_file_remove(lck_file, ptemp);

        }

#endif

        return OK;

    }



#if APR_HAS_SHARED_MEMORY

    /* initializing cache if shared memory size is not zero and we already don't have shm address */

    if (!st->cache_shm && st->cache_bytes > 0) {

#endif
@@ -1190,20 +1208,37 @@ static int util_ldap_post_config(apr_pool_t *p, apr_pool_t *plog, 
                         "LDAP cache: error while creating a shared memory segment: %s", buf);

        }





#if APR_HAS_SHARED_MEMORY

        if (st->cache_file) {

            st->lock_file = apr_pstrcat (st->pool, st->cache_file, ".lck", NULL);

        }

        else

#endif

            st->lock_file = ap_server_root_relative(st->pool, tmpnam(NULL));



        result = apr_global_mutex_create(&st->util_ldap_cache_lock, st->lock_file, APR_LOCK_DEFAULT, st->pool);

        if (result != APR_SUCCESS) {

            return result;

        }



        /* merge config in all vhost */

        s_vhost = s->next;

        while (s_vhost) {

            ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, result, s, 

                         "LDAP merging Shared Cache conf: shm=0x%pp rmm=0x%pp for VHOST: %s",

                         st->cache_shm, st->cache_rmm, s_vhost->server_hostname);



            st_vhost = (util_ldap_state_t *)ap_get_module_config(s_vhost->module_config, &ldap_module);



#if APR_HAS_SHARED_MEMORY

            st_vhost->cache_shm = st->cache_shm;

            st_vhost->cache_rmm = st->cache_rmm;

            st_vhost->cache_file = st->cache_file;

            ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, result, s, 

                         "LDAP merging Shared Cache conf: shm=0x%pp rmm=0x%pp for VHOST: %s",

                         st->cache_shm, st->cache_rmm, s_vhost->server_hostname);

#endif

            st_vhost->lock_file = st->lock_file;

            s_vhost = s_vhost->next;

        }

#if APR_HAS_SHARED_MEMORY

    }

    else {

        ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, "LDAP cache: LDAPSharedCacheSize is zero, disabling shared memory cache");
@@ -1368,6 +1403,22 @@ static int util_ldap_post_config(apr_pool_t *p, apr_pool_t *plog, 
    return(OK);

}



static void util_ldap_child_init(apr_pool_t *p, server_rec *s)

{

    apr_status_t sts;

    util_ldap_state_t *st =

        (util_ldap_state_t *)ap_get_module_config(s->module_config, &ldap_module);



    sts = apr_global_mutex_child_init(&st->util_ldap_cache_lock, st->lock_file, p);

    if (sts != APR_SUCCESS) {

        ap_log_error(APLOG_MARK, APLOG_CRIT, sts, s, "failed to init caching lock in child process");

        return;

    }

    else {

        ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, s, 

                     "INIT global mutex %s in child %d ", st->lock_file, getpid());

    }

}



command_rec util_ldap_cmds[] = {

    AP_INIT_TAKE1("LDAPSharedCacheSize", util_ldap_set_cache_bytes, NULL, RSRC_CONF,
@@ -1413,6 +1464,7 @@ static void util_ldap_register_hooks(apr_pool_t *p) 
{

    ap_hook_post_config(util_ldap_post_config,NULL,NULL,APR_HOOK_MIDDLE);

    ap_hook_handler(util_ldap_handler, NULL, NULL, APR_HOOK_MIDDLE);

    ap_hook_child_init(util_ldap_child_init, NULL, NULL, APR_HOOK_MIDDLE);

}



module ldap_module = {

modules/experimental/util_ldap_cache.c

+5 −1
Changes for modules/experimental/util_ldap_cache.c: 5 added lines, 1 removed line.
Original line number Diff line number Diff line
@@ -376,7 +376,12 @@ apr_status_t util_ldap_cache_module_kill(void *data) 
{

    util_ldap_state_t *st = (util_ldap_state_t *)data;



    util_ald_destroy_cache(st->util_ldap_cache);

#if APR_HAS_SHARED_MEMORY

    if (st->cache_rmm != NULL) {

        apr_rmm_destroy (st->cache_rmm);

        st->cache_rmm = NULL;

    }

    if (st->cache_shm != NULL) {

        apr_status_t result = apr_shm_destroy(st->cache_shm);

        st->cache_shm = NULL;
@@ -384,7 +389,6 @@ apr_status_t util_ldap_cache_module_kill(void *data) 
        return result;

    }

#endif

    util_ald_destroy_cache(st->util_ldap_cache);

    return APR_SUCCESS;

}

modules/experimental/util_ldap_cache.h

+0 −16
Changes for modules/experimental/util_ldap_cache.h: 0 added lines, 16 removed lines.
Original line number Diff line number Diff line
@@ -73,22 +73,6 @@ struct util_ald_cache { 


};



#if APR_HAS_THREADS

#define LDAP_CACHE_LOCK_CREATE(p) \

    if (!st->util_ldap_cache_lock) apr_thread_rwlock_create(&st->util_ldap_cache_lock, st->pool)

#define LDAP_CACHE_WRLOCK() \

    apr_thread_rwlock_wrlock(st->util_ldap_cache_lock)

#define LDAP_CACHE_UNLOCK() \

    apr_thread_rwlock_unlock(st->util_ldap_cache_lock)

#define LDAP_CACHE_RDLOCK() \

    apr_thread_rwlock_rdlock(st->util_ldap_cache_lock)

#else

#define LDAP_CACHE_LOCK_CREATE(p)

#define LDAP_CACHE_WRLOCK()

#define LDAP_CACHE_UNLOCK()

#define LDAP_CACHE_RDLOCK()

#endif



#ifndef WIN32

#define ALD_MM_FILE_MODE ( S_IRUSR|S_IWUSR )

#else