From: Anbang Wen <xofyarg@gmail.com>
Date: Sun, 13 May 2018 21:55:24 +0000 (-0700)
Subject: cache: restore kr_cache_match and kr_cache_remove
X-Git-Tag: v3.0.0~1^2~24
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f5b29467ef23800d3f063bd56d5c357eb4ff888a;p=thirdparty%2Fknot-resolver.git

cache: restore kr_cache_match and kr_cache_remove

1. Restore two cache op which got dropped in 2.0;
2. Add kr_unpack_cache_key to parse cache key;
3. Fix the lua binding for cache.get and cache.clear.
---

diff --git a/daemon/bindings.c b/daemon/bindings.c
index 5922c519e..95823d210 100644
--- a/daemon/bindings.c
+++ b/daemon/bindings.c
@@ -1075,18 +1075,9 @@ static int cache_close(lua_State *L)
 	return 1;
 }
 
-#if 0
 /** @internal Prefix walk. */
 static int cache_prefixed(struct kr_cache *cache, const char *args, knot_db_val_t *results, int maxresults)
 {
-	/* Decode parameters */
-	uint8_t namespace = 'R';
-	char *extra = strchr(args, ' ');
-	if (extra != NULL) {
-		extra[0] = '\0';
-		namespace = extra[1];
-	}
-
 	/* Convert to domain name */
 	uint8_t buf[KNOT_DNAME_MAXLEN];
 	if (!knot_dname_from_str(buf, args, sizeof(buf))) {
@@ -1094,7 +1085,7 @@ static int cache_prefixed(struct kr_cache *cache, const char *args, knot_db_val_
 	}
 
 	/* Start prefix search */
-	int ret = kr_cache_match(cache, namespace, buf, results, maxresults);
+	int ret = kr_cache_match(cache, buf, results, maxresults);
 	kr_cache_sync(cache);
 	return ret;
 }
@@ -1129,7 +1120,6 @@ static int cache_remove_prefix(struct kr_cache *cache, const char *args)
 	}
 	return ret;
 }
-#endif
 
 /** Prune expired/invalid records. */
 static int cache_prune(lua_State *L)
@@ -1170,7 +1160,7 @@ static int cache_clear(lua_State *L)
 
 	/* Clear a sub-tree in cache. */
 	if (args && strlen(args) > 0) {
-		int ret = kr_error(ENOSYS); // FIXME cache_remove_prefix(cache, args);
+		int ret = cache_remove_prefix(cache, args);
 		if (ret < 0) {
 			format_error(L, kr_strerror(ret));
 			lua_error(L);
@@ -1198,28 +1188,19 @@ static int cache_clear(lua_State *L)
 /** @internal Dump cache key into table on Lua stack. */
 static void cache_dump_key(lua_State *L, knot_db_val_t *key)
 {
-	char buf[KNOT_DNAME_MAXLEN];
-	/* Extract type */
-	uint16_t type = 0;
-	const char *endp = (const char *)key->data + key->len - sizeof(uint16_t);
-	memcpy(&type, endp, sizeof(uint16_t));
-	endp -= 1;
-	/* Extract domain name */
-	char *dst = buf;
-	const char *scan = endp - 1;
-	while (scan > (const char *)key->data) {
-		if (*scan == '\0') {
-			const size_t lblen = endp - scan - 1;
-			memcpy(dst, scan + 1, lblen);
-			dst += lblen;
-			*dst++ = '.';
-			endp = scan;
-		}
-		--scan;
+	knot_dname_t dname[KNOT_DNAME_MAXLEN];
+	char name[KNOT_DNAME_MAXLEN];
+	uint16_t type;
+
+	int ret = kr_unpack_cache_key(key, dname, &type);
+	if (ret < 0) {
+		return;
 	}
-	memcpy(dst, scan + 1, endp - scan);
+
+	knot_dname_to_str(name, dname, sizeof(dname));
+
 	/* If name typemap doesn't exist yet, create it */
-	lua_getfield(L, -1, buf);
+	lua_getfield(L, -1, name);
 	if (lua_isnil(L, -1)) {
 		lua_pop(L, 1);
 		lua_newtable(L);
@@ -1230,7 +1211,7 @@ static void cache_dump_key(lua_State *L, knot_db_val_t *key)
 	lua_pushboolean(L, true);
 	lua_setfield(L, -2, type_buf);
 	/* Set name typemap */
-	lua_setfield(L, -2, buf);
+	lua_setfield(L, -2, name);
 }
 
 /** Query cached records. */
@@ -1246,9 +1227,9 @@ static int cache_get(lua_State *L)
 	}
 
 	/* Retrieve set of keys */
-	//const char *args = lua_tostring(L, 1);
+	const char *args = lua_tostring(L, 1);
 	static knot_db_val_t result_set[100];
-	int ret = kr_error(ENOSYS); // FIXME cache_prefixed(cache, args, result_set, 100);
+	int ret = cache_prefixed(cache, args, result_set, 100);
 	if (ret < 0) {
 		format_error(L, kr_strerror(ret));
 		lua_error(L);
diff --git a/lib/cache/api.c b/lib/cache/api.c
index e08f7e29e..2ed8290aa 100644
--- a/lib/cache/api.c
+++ b/lib/cache/api.c
@@ -762,3 +762,72 @@ int kr_cache_peek_exact(struct kr_cache *cache, const knot_dname_t *name, uint16
 	return ret;
 }
 
+int kr_cache_remove(struct kr_cache *cache, const knot_dname_t *name,
+		    uint16_t type)
+{
+	if (!cache_isvalid(cache)) {
+		return kr_error(EINVAL);
+	}
+	if (!cache->api->remove) {
+		return kr_error(ENOSYS);
+	}
+	struct key k_storage, *k = &k_storage;
+	int ret = kr_dname_lf(k->buf, name, false);
+	if (ret) return kr_error(ret);
+
+	knot_db_val_t key = key_exact_type(k, type);
+	return cache_op(cache, remove, &key, 1);
+}
+
+int kr_cache_match(struct kr_cache *cache, const knot_dname_t *name,
+		   knot_db_val_t *keys, int max)
+{
+	if (!cache_isvalid(cache)) {
+		return kr_error(EINVAL);
+	}
+	if (!cache->api->match) {
+		return kr_error(ENOSYS);
+	}
+
+	struct key k_storage, *k = &k_storage;
+
+	int ret = kr_dname_lf(k->buf, name, false);
+	if (ret) return kr_error(ret);
+
+	// use a mock type
+	knot_db_val_t key = key_exact_type(k, KNOT_RRTYPE_A);
+	key.len -= sizeof((char)('E')) + sizeof(uint16_t);
+	return cache_op(cache, match, &key, keys, max);
+}
+
+int kr_unpack_cache_key(knot_db_val_t *key, knot_dname_t *buf, uint16_t *type)
+{
+	if (key == NULL || buf == NULL) {
+		return kr_error(EINVAL);
+	}
+
+	int len = -1;
+	const void *endp;
+	for (endp = key->data + 1;
+	     endp < key->data + key->len; endp++) {
+		if (*(const char *)(endp-1) == '\0' &&
+		    (*(const char *)endp == 'E')) {
+			len = endp - key->data - 1;
+			break;
+		}
+	}
+
+	if (len == -1 || len > KNOT_DNAME_MAXLEN) {
+		return kr_error(EINVAL);
+	}
+
+	int ret = knot_dname_lf2wire(buf, len, key->data);
+	if (ret < 0) {
+		return kr_error(ret);
+	}
+
+	// jump over "\0 E/1"
+	memcpy(type, key->data + len + 2, sizeof(uint16_t));
+
+	return kr_ok();
+}
diff --git a/lib/cache/api.h b/lib/cache/api.h
index ed73eb7c3..9404fabd5 100644
--- a/lib/cache/api.h
+++ b/lib/cache/api.h
@@ -137,3 +137,34 @@ int kr_cache_materialize(knot_rdataset_t *dst, const struct kr_cache_p *ref,
 			 knot_mm_t *pool);
 
 
+/**
+ * Remove an entry from cache.
+ * @param cache cache structure
+ * @param name dname
+ * @param type rr type
+ * @return 0 or an errcode
+ */
+KR_EXPORT
+int kr_cache_remove(struct kr_cache *cache, const knot_dname_t *name,
+		    uint16_t type);
+
+/**
+ * Get keys matching a dname lf prefix
+ * @param cache cache structure
+ * @param name dname
+ * @param keys matched keys
+ * @return result count or an errcode
+ */
+KR_EXPORT
+int kr_cache_match(struct kr_cache *cache, const knot_dname_t *name,
+		   knot_db_val_t *keys, int max);
+
+/**
+ * Unpack dname and type from db key
+ * @param key db key representation
+ * @param buf output buffer of domain name in dname format
+ * @param type output for type
+ * @return length of dname or an errcode
+ */
+KR_EXPORT
+int kr_unpack_cache_key(knot_db_val_t *key, knot_dname_t *buf, uint16_t *type);
diff --git a/lib/cache/cdb_lmdb.c b/lib/cache/cdb_lmdb.c
index 71d6adc00..2b07f9a1b 100644
--- a/lib/cache/cdb_lmdb.c
+++ b/lib/cache/cdb_lmdb.c
@@ -571,12 +571,6 @@ static int cdb_match(knot_db_t *db, knot_db_val_t *key, knot_db_val_t *val, int
 		return ret;
 	}
 
-	/* Turn wildcard into prefix scan. */
-	const uint8_t *endp = (const uint8_t *)key->data + (key->len - 2);
-	if (key->len > 2 && endp[0] == '*' && endp[1] == '\0') {
-		key->len -= 2; /* Skip '*' label */
-	}
-
 	MDB_cursor *cur = NULL;
 	ret = mdb_cursor_open(txn, env->dbi, &cur);
 	if (ret != 0) {