1 files changed, 377 insertions, 0 deletions
diff --git a/runtime/lookup.c b/runtime/lookup.c
new file mode 100644
index 0000000..f7ed899
--- /dev/null
+++ b/runtime/lookup.c
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+/* lookup.c
+ * Support for lookup tables in RainerScript.
+ *
+ * Copyright 2013 Adiscon GmbH.
+ *
+ * This file is part of the rsyslog runtime library.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *       -or-
+ *       see COPYING.ASL20 in the source distribution
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "config.h"
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <json.h>
+#include <assert.h>
+
+#include "rsyslog.h"
+#include "srUtils.h"
+#include "errmsg.h"
+#include "lookup.h"
+#include "msg.h"
+#include "rsconf.h"
+#include "dirty.h"
+#include "unicode-helper.h"
+
+/* definitions for objects we access */
+DEFobjStaticHelpers
+DEFobjCurrIf(errmsg)
+DEFobjCurrIf(glbl)
+
+/* forward definitions */
+static rsRetVal lookupReadFile(lookup_t *pThis);
+
+/* static data */
+/* tables for interfacing with the v6 config system (as far as we need to) */
+static struct cnfparamdescr modpdescr[] = {
+	{ "name", eCmdHdlrString, CNFPARAM_REQUIRED },
+	{ "file", eCmdHdlrString, CNFPARAM_REQUIRED }
+};
+static struct cnfparamblk modpblk =
+	{ CNFPARAMBLK_VERSION,
+	  sizeof(modpdescr)/sizeof(struct cnfparamdescr),
+	  modpdescr
+	};
+
+
+/* create a new lookup table object AND include it in our list of
+ * lookup tables.
+ */
+rsRetVal
+lookupNew(lookup_t **ppThis)
+{
+	lookup_t *pThis = NULL;
+	DEFiRet;
+
+	CHKmalloc(pThis = malloc(sizeof(lookup_t)));
+	pthread_rwlock_init(&pThis->rwlock, NULL);
+	pThis->name = NULL;
+
+	if(loadConf->lu_tabs.root == NULL) {
+		loadConf->lu_tabs.root = pThis;
+		pThis->next = NULL;
+	} else {
+		pThis->next = loadConf->lu_tabs.last;
+	}
+	loadConf->lu_tabs.last = pThis;
+
+	*ppThis = pThis;
+finalize_it:
+	if(iRet != RS_RET_OK) {
+		free(pThis);
+	}
+	RETiRet;
+}
+void
+lookupDestruct(lookup_t *pThis)
+{
+	pthread_rwlock_destroy(&pThis->rwlock);
+	free(pThis->name);
+	free(pThis);
+}
+
+void
+lookupInitCnf(lookup_tables_t *lu_tabs)
+{
+	lu_tabs->root = NULL;
+	lu_tabs->last = NULL;
+}
+
+
+/* comparison function for qsort() and string array compare
+ * this is for the string lookup table type
+ */
+static int
+qs_arrcmp_strtab(const void *s1, const void *s2)
+{
+	return ustrcmp(((lookup_string_tab_etry_t*)s1)->key, ((lookup_string_tab_etry_t*)s2)->key);
+}
+/* comparison function for bsearch() and string array compare
+ * this is for the string lookup table type
+ */
+static int
+bs_arrcmp_strtab(const void *s1, const void *s2)
+{
+	return strcmp((char*)s1, (char*)((lookup_string_tab_etry_t*)s2)->key);
+}
+
+rsRetVal
+lookupBuildTable(lookup_t *pThis, struct json_object *jroot)
+{
+	//struct json_object *jversion, *jnomatch, *jtype, *jtab;
+	struct json_object *jtab;
+	struct json_object *jrow, *jindex, *jvalue;
+	uint32_t i;
+	uint32_t maxStrSize;
+	DEFiRet;
+
+#if 0 // enable when we continue to work on this module
+	jversion = json_object_object_get(jroot, "version");
+	jnomatch = json_object_object_get(jroot, "nomatch");
+	jtype = json_object_object_get(jroot, "type");
+#endif
+	jtab = json_object_object_get(jroot, "table");
+	pThis->nmemb = json_object_array_length(jtab);
+	CHKmalloc(pThis->d.strtab = malloc(pThis->nmemb * sizeof(lookup_string_tab_etry_t)));
+
+	maxStrSize = 0;
+	for(i = 0 ; i < pThis->nmemb ; ++i) {
+		jrow = json_object_array_get_idx(jtab, i);
+		jindex = json_object_object_get(jrow, "index");
+		jvalue = json_object_object_get(jrow, "value");
+		CHKmalloc(pThis->d.strtab[i].key = (uchar*) strdup(json_object_get_string(jindex)));
+		CHKmalloc(pThis->d.strtab[i].val = (uchar*) strdup(json_object_get_string(jvalue)));
+		maxStrSize += ustrlen(pThis->d.strtab[i].val);
+	}
+
+	qsort(pThis->d.strtab, pThis->nmemb, sizeof(lookup_string_tab_etry_t), qs_arrcmp_strtab);
+dbgprintf("DDDD: table loaded (max size %u):\n", maxStrSize);
+for(i = 0 ; i < pThis->nmemb ; ++i)
+  dbgprintf("key: '%s', val: '%s'\n", pThis->d.strtab[i].key, pThis->d.strtab[i].val);
+
+finalize_it:
+	RETiRet;
+}
+
+
+/* find a lookup table. This is a naive O(n) algo, but this really
+ * doesn't matter as it is called only a few times during config
+ * load. The function returns either a pointer to the requested
+ * table or NULL, if not found.
+ */
+lookup_t *
+lookupFindTable(uchar *name)
+{
+	lookup_t *curr;
+
+	for(curr = loadConf->lu_tabs.root ; curr != NULL ; curr = curr->next) {
+		if(!ustrcmp(curr->name, name))
+			break;
+	}
+	return curr;
+}
+
+
+/* this reloads a lookup table. This is done while the engine is running,
+ * as such the function must ensure proper locking and proper order of
+ * operations (so that nothing can interfere). If the table cannot be loaded,
+ * the old table is continued to be used.
+ */
+static rsRetVal
+lookupReload(lookup_t *pThis)
+{
+	uint32_t i;
+	lookup_t newlu; /* dummy to be able to use support functions without 
+	                   affecting current settings. */
+	DEFiRet;
+	
+	DBGPRINTF("reload requested for lookup table '%s'\n", pThis->name);
+	memset(&newlu, 0, sizeof(newlu));
+	CHKmalloc(newlu.name = ustrdup(pThis->name));
+	CHKmalloc(newlu.filename = ustrdup(pThis->filename));
+	CHKiRet(lookupReadFile(&newlu));
+	/* all went well, copy over data members */
+	pthread_rwlock_wrlock(&pThis->rwlock);
+	for(i = 0 ; i < pThis->nmemb ; ++i) {
+		free(pThis->d.strtab[i].key), /* we don't care about exec order of frees */
+		free(pThis->d.strtab[i].val);
+	}
+	free(pThis->d.strtab);
+	pThis->d.strtab = newlu.d.strtab; /* hand table AND ALL STRINGS over! */
+	pthread_rwlock_unlock(&pThis->rwlock);
+	errmsg.LogError(0, RS_RET_OK, "lookup table '%s' reloaded from file '%s'",
+			pThis->name, pThis->filename);
+finalize_it:
+	free(newlu.name);
+	free(newlu.filename);
+	RETiRet;
+}
+
+
+/* reload all lookup tables on HUP */
+void
+lookupDoHUP()
+{
+	lookup_t *lu;
+	for(lu = loadConf->lu_tabs.root ; lu != NULL ; lu = lu->next) {
+		lookupReload(lu);
+	}
+}
+
+
+/* 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.
+ */
+es_str_t *
+lookupKey_estr(lookup_t *pThis, uchar *key)
+{
+	lookup_string_tab_etry_t *etry;
+	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 = ""; // TODO: use set default 
+	} else {
+		r = (char*)etry->val;
+	}
+	estr = es_newStrFromCStr(r, strlen(r));
+	pthread_rwlock_unlock(&pThis->rwlock);
+	return estr;
+}
+
+
+/* note: widely-deployed json_c 0.9 does NOT support incremental
+ * parsing. In order to keep compatible with e.g. Ubuntu 12.04LTS,
+ * we read the file into one big memory buffer and parse it at once.
+ * While this is not very elegant, it will not pose any real issue
+ * for "reasonable" lookup tables (and "unreasonably" large ones
+ * will probably have other issues as well...).
+ */
+static rsRetVal
+lookupReadFile(lookup_t *pThis)
+{
+	struct json_tokener *tokener = NULL;
+	struct json_object *json = NULL;
+	int eno = errno;
+	char errStr[1024];
+	char *iobuf = NULL;
+	int fd;
+	ssize_t nread;
+	struct stat sb;
+	DEFiRet;
+
+
+	if(stat((char*)pThis->filename, &sb) == -1) {
+		eno = errno;
+		errmsg.LogError(0, RS_RET_FILE_NOT_FOUND,
+			"lookup table file '%s' stat failed: %s",
+			pThis->filename, rs_strerror_r(eno, errStr, sizeof(errStr)));
+		ABORT_FINALIZE(RS_RET_FILE_NOT_FOUND);
+	}
+
+	CHKmalloc(iobuf = malloc(sb.st_size));
+
+	if((fd = open((const char*) pThis->filename, O_RDONLY)) == -1) {
+		eno = errno;
+		errmsg.LogError(0, RS_RET_FILE_NOT_FOUND,
+			"lookup table file '%s' could not be opened: %s",
+			pThis->filename, rs_strerror_r(eno, errStr, sizeof(errStr)));
+		ABORT_FINALIZE(RS_RET_FILE_NOT_FOUND);
+	}
+
+	tokener = json_tokener_new();
+	nread = read(fd, iobuf, sb.st_size);
+	if(nread != (ssize_t) sb.st_size) {
+		eno = errno;
+		errmsg.LogError(0, RS_RET_READ_ERR,
+			"lookup table file '%s' read error: %s",
+			pThis->filename, rs_strerror_r(eno, errStr, sizeof(errStr)));
+		ABORT_FINALIZE(RS_RET_READ_ERR);
+	}
+
+	json = json_tokener_parse_ex(tokener, iobuf, sb.st_size);
+	if(json == NULL) {
+		errmsg.LogError(0, RS_RET_JSON_PARSE_ERR,
+			"lookup table file '%s' json parsing error",
+			pThis->filename);
+		ABORT_FINALIZE(RS_RET_JSON_PARSE_ERR);
+	}
+	free(iobuf); /* early free to sever resources*/
+	iobuf = NULL; /* make sure no double-free */
+
+	/* got json object, now populate our own in-memory structure */
+	CHKiRet(lookupBuildTable(pThis, json));
+
+finalize_it:
+	free(iobuf);
+	if(tokener != NULL)
+		json_tokener_free(tokener);
+	if(json != NULL)
+		json_object_put(json);
+	RETiRet;
+}
+
+
+rsRetVal
+lookupProcessCnf(struct cnfobj *o)
+{
+	struct cnfparamvals *pvals;
+	lookup_t *lu;
+	short i;
+	DEFiRet;
+
+	pvals = nvlstGetParams(o->nvlst, &modpblk, NULL);
+	if(pvals == NULL) {
+		ABORT_FINALIZE(RS_RET_MISSING_CNFPARAMS);
+	}
+	DBGPRINTF("lookupProcessCnf params:\n");
+	cnfparamsPrint(&modpblk, pvals);
+	
+	CHKiRet(lookupNew(&lu));
+
+	for(i = 0 ; i < modpblk.nParams ; ++i) {
+		if(!pvals[i].bUsed)
+			continue;
+		if(!strcmp(modpblk.descr[i].name, "file")) {
+			CHKmalloc(lu->filename = (uchar*)es_str2cstr(pvals[i].val.d.estr, NULL));
+		} else if(!strcmp(modpblk.descr[i].name, "name")) {
+			CHKmalloc(lu->name = (uchar*)es_str2cstr(pvals[i].val.d.estr, NULL));
+		} else {
+			dbgprintf("lookup_table: program error, non-handled "
+			  "param '%s'\n", modpblk.descr[i].name);
+		}
+	}
+	CHKiRet(lookupReadFile(lu));
+	DBGPRINTF("lookup table '%s' loaded from file '%s'\n", lu->name, lu->filename);
+
+finalize_it:
+	cnfparamvalsDestruct(pvals, &modpblk);
+	RETiRet;
+}
+
+void
+lookupClassExit(void)
+{
+	objRelease(glbl, CORE_COMPONENT);
+	objRelease(errmsg, CORE_COMPONENT);
+}
+
+rsRetVal
+lookupClassInit(void)
+{
+	DEFiRet;
+	CHKiRet(objGetObjInterface(&obj));
+	CHKiRet(objUse(glbl, CORE_COMPONENT));
+	CHKiRet(objUse(errmsg, CORE_COMPONENT));
+finalize_it:
+	RETiRet;
+}