improved performance of regexp-based filters

Thanks to Arnaud Cornet for providing the idea and initial patch.

4 files changed, 39 insertions, 2 deletions

diff --git a/runtime/stringbuf.c b/runtime/stringbuf.c
index a5dc625a..c0a19ae4 100644
--- a/runtime/stringbuf.c
+++ b/runtime/stringbuf.c
@@ -724,6 +724,36 @@ finalize_it:
 	RETiRet;
 }
 
+/* same as above, only not braindead */
+int rsCStrSzStrMatchRegexCache(cstr_t *pCS1, uchar *psz, void **rc)
+{
+   int ret;
+
+   BEGINfunc
+
+   if(objUse(regexp, LM_REGEXP_FILENAME) == RS_RET_OK) {
+      regex_t **cache = rc;
+      if (*cache == NULL) {
+         *cache = calloc(sizeof(regex_t), 1);
+         regexp.regcomp(*cache, (char*) rsCStrGetSzStr(pCS1), 0);
+      }
+      ret = regexp.regexec(*cache, (char*) psz, 0, NULL, 0);
+   } else {
+      ret = 1; /* simulate "not found" */
+   }
+
+   ENDfunc
+   return ret;
+}
+
+/* free a cached compiled regex */
+void rsRegexDestruct(void **rc) {
+   regex_t **cache = rc;
+   regexp.regfree(*cache);
+   free(*cache);
+   *cache = NULL;
+}
+
 
 /* compare a rsCStr object with a classical sz string.  This function
  * is almost identical to rsCStrZsStrCmp(), but it also takes an offset
diff --git a/runtime/stringbuf.h b/runtime/stringbuf.h
index f3e08439..4b0fb065 100644
--- a/runtime/stringbuf.h
+++ b/runtime/stringbuf.h
@@ -137,6 +137,8 @@ int rsCStrStartsWithSzStr(cstr_t *pCS1, uchar *psz, size_t iLenSz);
 int rsCStrCaseInsensitveStartsWithSzStr(cstr_t *pCS1, uchar *psz, size_t iLenSz);
 int rsCStrSzStrStartsWithCStr(cstr_t *pCS1, uchar *psz, size_t iLenSz);
 rsRetVal rsCStrSzStrMatchRegex(cstr_t *pCS1, uchar *psz, int iType);
+int rsCStrSzStrMatchRegexCache(cstr_t *pCS1, uchar *psz, void **cache);
+void rsRegexDestruct(void **rc);
 rsRetVal rsCStrConvertToNumber(cstr_t *pStr, number_t *pNumber);
 rsRetVal rsCStrConvertToBool(cstr_t *pStr, number_t *pBool);
 rsRetVal rsCStrAppendCStr(cstr_t *pThis, cstr_t *pstrAppend);
diff --git a/tools/syslogd.c b/tools/syslogd.c
index 16f255ea..c7f36b45 100644
--- a/tools/syslogd.c
+++ b/tools/syslogd.c
@@ -432,6 +432,8 @@ selectorDestruct(void *pVal)
 	} else if(pThis->f_filter_type == FILTER_EXPR) {
 		if(pThis->f_filterData.f_expr != NULL)
 			expr.Destruct(&pThis->f_filterData.f_expr);
+		if(pThis->regex_cache != NULL)
+			rsRegexDestruct(&pThis->regex_cache);
 	}
 
 	llDestroy(&pThis->llActList);
@@ -1075,8 +1077,10 @@ static rsRetVal shouldProcessThisMessage(selector_t *f, msg_t *pMsg, int *bProce
 				bRet = 1; /* process message! */
 			break;
 		case FIOP_REGEX:
-			if(rsCStrSzStrMatchRegex(f->f_filterData.prop.pCSCompValue,
-					  (unsigned char*) pszPropVal, 0) == RS_RET_OK)
+			//TODO REGEX: this needs to be merged with new functionality below
+			//rgerhards, 2009-04-02
+			if(rsCStrSzStrMatchRegexCache(f->f_filterData.prop.pCSCompValue,
+					(unsigned char*) pszPropVal, &f->regex_cache) == 0)
 				bRet = 1;
 			break;
 		case FIOP_EREREGEX:
diff --git a/tools/syslogd.h b/tools/syslogd.h
index f1b11a91..ecaaec34 100644
--- a/tools/syslogd.h
+++ b/tools/syslogd.h
@@ -80,6 +80,7 @@ struct filed {
 	} f_filterData;
 
 	linkedList_t llActList;	/* list of configured actions */
+regex_t *regex_cache;
 };