add locking to rlm_cache

diff --git a/src/modules/rlm_cache/rlm_cache.c b/src/modules/rlm_cache/rlm_cache.c
index 816a2eb..4fcb569 100644 (file)
--- a/src/modules/rlm_cache/rlm_cache.c
+++ b/src/modules/rlm_cache/rlm_cache.c
@@ -44,6 +44,9 @@ typedef struct rlm_cache_t {
        CONF_SECTION    *cs;
        rbtree_t        *cache;
        fr_heap_t       *heap;
+#ifdef HAVE_PTHREAD_H
+       pthread_mutex_t cache_mutex;
+#endif
 } rlm_cache_t;
 
 typedef struct rlm_cache_entry_t {
@@ -57,6 +60,14 @@ typedef struct rlm_cache_entry_t {
        VALUE_PAIR      *reply;
 } rlm_cache_entry_t;
 
+#ifdef HAVE_PTHREAD_H
+#define PTHREAD_MUTEX_LOCK pthread_mutex_lock
+#define PTHREAD_MUTEX_UNLOCK pthread_mutex_unlock
+#else
+#define PTHREAD_MUTEX_LOCK(_x)
+#define PTHREAD_MUTEX_UNLOCK(_x)
+#endif
+
 
 /*
  *     Compare two entries by key.  There may only be one entry with
@@ -371,15 +382,16 @@ static size_t cache_xlat(void *instance, REQUEST *request,
        DICT_ATTR *target;
        const char *p = fmt;
        char buffer[1024];
+       int ret=0;
 
        radius_xlat(buffer, sizeof(buffer), inst->key, request, NULL, NULL);
 
+       PTHREAD_MUTEX_LOCK(&inst->cache_mutex);
        c = cache_find(inst, request, buffer);
        
        if (!c) {
                RDEBUG("No cache entry for key \"%s\"", buffer);
-               
-               return 0;
+               goto done;
        }
        
        list = radius_list_name(&p, PAIR_LIST_REQUEST);
@@ -409,18 +421,20 @@ static size_t cache_xlat(void *instance, REQUEST *request,
        target = dict_attrbyname(p);
        if (!target) {
                radlog(L_ERR, "rlm_cache: Unknown attribute \"%s\"", p);
-               
-               return 0;
+               goto done;
        }
        
        vp = pairfind(vps, target->attr, target->vendor);
        if (!vp) {
                RDEBUG("No instance of this attribute has been cached");
-               
-               return 0;
+               goto done;
        }
        
-       return vp_prints_value(out, freespace, vp, 0);
+       ret = vp_prints_value(out, freespace, vp, 0);
+done:
+       PTHREAD_MUTEX_UNLOCK(&inst->cache_mutex);
+       return ret;
+
 }
 
 
@@ -460,6 +474,9 @@ static int cache_detach(void *instance)
 
        fr_heap_delete(inst->heap);
        rbtree_free(inst->cache);
+#ifdef HAVE_PTHREAD_H
+       pthread_mutex_destroy(&inst->cache_mutex);
+#endif
        free(instance);
        return 0;
 }
@@ -519,6 +536,14 @@ static int cache_instantiate(CONF_SECTION *conf, void **instance)
                return -1;
        }
 
+#ifdef HAVE_PTHREAD_H
+       if (pthread_mutex_init(&inst->cache_mutex, NULL) < 0) {
+               radlog(L_ERR, "rlm_cache: Failed initializing mutex: %s", strerror(errno));
+               cache_detach(inst);
+               return -1;
+       }
+#endif
+
        /*
         *      The cache.
         */
@@ -574,9 +599,11 @@ static int cache_it(void *instance, REQUEST *request)
        rlm_cache_t *inst = instance;
        VALUE_PAIR *vp;
        char buffer[1024];
+       int retcode;
 
        radius_xlat(buffer, sizeof(buffer), inst->key, request, NULL, NULL);
 
+       PTHREAD_MUTEX_LOCK(&inst->cache_mutex);
        c = cache_find(inst, request, buffer);
        
        /*
@@ -584,22 +611,31 @@ static int cache_it(void *instance, REQUEST *request)
         */
        vp = pairfind(request->config_items, PW_CACHE_STATUS_ONLY, 0);
        if (vp && vp->vp_integer) {
-               return c ?
-                       RLM_MODULE_OK:
-                       RLM_MODULE_NOTFOUND;
+               if (c) {
+                       retcode = RLM_MODULE_OK;
+               } else {
+                       retcode = RLM_MODULE_NOTFOUND;
+               }
+               goto done;
        }
        
        if (c) {
                cache_merge(inst, request, c);
-               return RLM_MODULE_OK;
+               retcode = RLM_MODULE_OK;
+               goto done;
        }
 
        c = cache_add(inst, request, buffer);
-       if (!c) return RLM_MODULE_NOOP;
+       if (!c) {
+               retcode = RLM_MODULE_NOOP;
+               goto done;
+       }
 
        cache_merge(inst, request, c);
-
-       return RLM_MODULE_UPDATED;
+       retcode = RLM_MODULE_UPDATED;
+done:
+       PTHREAD_MUTEX_UNLOCK(&inst->cache_mutex);
+       return retcode;
 }