add base plumbing for (later) dynamic table reload

among others, we change some internal interfaces. So far, we only
add the necessary locks. More work in later commits.

3 files changed, 23 insertions, 11 deletions

diff --git a/grammar/rainerscript.c b/grammar/rainerscript.c
index ef44a410..53e56f05 100644
--- a/grammar/rainerscript.c
+++ b/grammar/rainerscript.c
@@ -1481,8 +1481,7 @@ dbgprintf("DDDD: executing lookup\n");
 		}
 		cnfexprEval(func->expr[1], &r[1], usrptr);
 		str = (char*) var2CString(&r[1], &bMustFree);
-		s = (char*)lookupKey(func->funcdata, (uchar*)str);
-		ret->d.estr = es_newStrFromCStr(s, strlen(s));
+		ret->d.estr = lookupKey_estr(func->funcdata, (uchar*)str);
 		if(bMustFree) free(str);
 		if(r[1].datatype == 'S') es_deleteStr(r[1].d.estr);
 		break;
diff --git a/runtime/lookup.c b/runtime/lookup.c
index e83f5979..b0780354 100644
--- a/runtime/lookup.c
+++ b/runtime/lookup.c
@@ -67,6 +67,7 @@ lookupNew(lookup_t **ppThis)
 	DEFiRet;
 
 	CHKmalloc(pThis = malloc(sizeof(lookup_t)));
+	pthread_rwlock_init(&pThis->rwlock, NULL);
 	pThis->name = NULL;
 
 	if(loadConf->lu_tabs.root == NULL) {
@@ -85,9 +86,11 @@ finalize_it:
 	RETiRet;
 }
 void
-lookupDestruct(lookup_t *lookup)
+lookupDestruct(lookup_t *pThis)
 {
-	free(lookup);
+	pthread_rwlock_destroy(&pThis->rwlock);
+	free(pThis->name);
+	free(pThis);
 }
 
 void
@@ -171,19 +174,26 @@ lookupFindTable(uchar *name)
 
 /* returns either a pointer to the value (read only!) or NULL
  * if either the key could not be found or an error occured.
+ * Note that an estr_t object is returned. The caller is 
+ * responsible for freeing it.
  */
-uchar *
-lookupKey(lookup_t *pThis, uchar *key)
+es_str_t *
+lookupKey_estr(lookup_t *pThis, uchar *key)
 {
 	lookup_string_tab_etry_t *etry;
-	uchar *r;
+	char *r;
+	es_str_t *estr;
+
+	pthread_rwlock_rdlock(&pThis->rwlock);
 	etry = bsearch(key, pThis->d.strtab, pThis->nmemb, sizeof(lookup_string_tab_etry_t), bs_arrcmp_strtab);
 	if(etry == NULL) {
-		r = (uchar*)""; // TODO: use set default 
+		r = ""; // TODO: use set default 
 	} else {
-		r = etry->val;
+		r = (char*)etry->val;
 	}
-	return r;
+	estr = es_newStrFromCStr(r, strlen(r));
+	pthread_rwlock_unlock(&pThis->rwlock);
+	return estr;
 }
 
 
diff --git a/runtime/lookup.h b/runtime/lookup.h
index db2737a2..12bd9336 100644
--- a/runtime/lookup.h
+++ b/runtime/lookup.h
@@ -20,6 +20,7 @@
  */
 #ifndef INCLUDED_LOOKUP_H
 #define INCLUDED_LOOKUP_H
+#include <libestr.h>
 
 struct lookup_tables_s {
 	lookup_t *root;	/* the root of the template list */
@@ -31,7 +32,9 @@ struct lookup_string_tab_etry_s {
 	uchar *val;
 };
 
+/* a single lookup table */
 struct lookup_s {
+	pthread_rwlock_t rwlock;	/* protect us in case of dynamic reloads */
 	uchar *name;
 	uchar *filename;
 	uint32_t nmemb;
@@ -45,7 +48,7 @@ struct lookup_s {
 void lookupInitCnf(lookup_tables_t *lu_tabs);
 rsRetVal lookupProcessCnf(struct cnfobj *o);
 lookup_t *lookupFindTable(uchar *name);
-uchar *lookupKey(lookup_t *pThis, uchar *key);
+es_str_t *lookupKey(lookup_t *pThis, uchar *key);
 void lookupDestruct(lookup_t *pThis);
 void lookupClassExit(void);
 rsRetVal lookupClassInit(void);