From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp63.i.mail.ru (smtp63.i.mail.ru [217.69.128.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dev.tarantool.org (Postfix) with ESMTPS id 3FABA4696C3 for ; Tue, 24 Dec 2019 01:41:53 +0300 (MSK) From: Vladislav Shpilevoy Date: Mon, 23 Dec 2019 23:41:48 +0100 Message-Id: <679a1d9daedb82276388320f4078be590c1979df.1577140688.git.v.shpilevoy@tarantool.org> In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [Tarantool-patches] [PATCH 1/3] tuple: make update operation tokens consumable List-Id: Tarantool development patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: tarantool-patches@dev.tarantool.org There is a case: [1][2][3][4] = 100. It is not a problem when it is a single operation, not intersecting with anything. It is an isolated update then, and works ok. But the next patch allows several update operations have the same prefix, and the path [1][2][3][4] can become a tree of updated arrays. For example, a trivial tree like this: root: [ [1] ] | [ [1] [2] ] | [ [1] [2] [3] ] | [ [1] [2] [3] [4] ] =100 When the update is applied to root, the JSON path [1][2][3][4] is decoded one part by one. And the operation goes down the tree until reaches the leaf, where [4] = 100 is applied. Each time when the update goes one level down, somebody should update xrow_update_op.field_no so as on the first level it would be 1, then 2, 3, 4. Does it mean that each level of the update [1][2][3][4] should prepare field_no for the next child? No, because then they would need to check type of the child if it is an array or map, or whatever expects a valid field_no/key in xrow_update_op, and ensure that map-child gets a key, array-child gets a field_no. That would complicate the code to a totally unreadable state, and would break encapsulation between xrow_update_array/map/bar... . Each array update operation would check a child for all existing types to ensure that the next token matches it. The same would happen to map updates. This patch goes another way - let each level of update check if its field_no/key is already prepared by the caller. And if not, extract a next token from the operation path. So the map update will ensure that it has a valid key, an array update will ensure that it has a valid field no. Part of #1261 --- src/box/xrow_update_array.c | 47 +++++++++++++++++++++++++++++++++++-- src/box/xrow_update_field.c | 22 +++++++++++++++++ src/box/xrow_update_field.h | 25 ++++++++++++++++++-- 3 files changed, 90 insertions(+), 4 deletions(-) diff --git a/src/box/xrow_update_array.c b/src/box/xrow_update_array.c index 57427e39c..6a7ce09ff 100644 --- a/src/box/xrow_update_array.c +++ b/src/box/xrow_update_array.c @@ -32,6 +32,31 @@ #include "msgpuck.h" #include "fiber.h" +/** + * Make sure @a op contains a valid field number to where the + * operation should be applied next. Field number may be not + * known, if the array's parent didn't propagate operation's + * lexer. In fact, the parent fills fieldno only in some rare + * cases like branching. Generally, an array should care about + * fieldno by itself. + */ +static inline int +xrow_update_op_prepare_num_token(struct xrow_update_op *op) +{ + /* + * Token type END is a special value meaning that the + * current token needs to be parsed. + */ + if (op->token_type == JSON_TOKEN_END && + xrow_update_op_consume_token(op) != 0) + return -1; + if (op->token_type != JSON_TOKEN_NUM) { + return xrow_update_err(op, "can't update an array by not a "\ + "number index"); + } + return 0; +} + /** * Make field index non-negative and check for the field * existence. @@ -39,6 +64,7 @@ static inline int xrow_update_op_adjust_field_no(struct xrow_update_op *op, int32_t field_count) { + assert(op->token_type == JSON_TOKEN_NUM); if (op->field_no >= 0) { if (op->field_no < field_count) return 0; @@ -221,10 +247,14 @@ xrow_update_op_do_array_insert(struct xrow_update_op *op, { assert(field->type == XUPDATE_ARRAY); struct xrow_update_array_item *item; + if (xrow_update_op_prepare_num_token(op) != 0) + return -1; + if (!xrow_update_op_is_term(op)) { item = xrow_update_array_extract_item(field, op); if (item == NULL) return -1; + op->token_type = JSON_TOKEN_END; return xrow_update_op_do_field_insert(op, &item->field); } @@ -248,6 +278,9 @@ xrow_update_op_do_array_set(struct xrow_update_op *op, { assert(field->type == XUPDATE_ARRAY); struct xrow_update_rope *rope = field->array.rope; + if (xrow_update_op_prepare_num_token(op) != 0) + return -1; + /* Interpret '=' for n + 1 field as insert. */ if (op->field_no == (int32_t) xrow_update_rope_size(rope)) return xrow_update_op_do_array_insert(op, field); @@ -256,8 +289,10 @@ xrow_update_op_do_array_set(struct xrow_update_op *op, xrow_update_array_extract_item(field, op); if (item == NULL) return -1; - if (!xrow_update_op_is_term(op)) + if (!xrow_update_op_is_term(op)) { + op->token_type = JSON_TOKEN_END; return xrow_update_op_do_field_set(op, &item->field); + } op->new_field_len = op->arg.set.length; /* * Ignore the previous op, if any. It is not correct, @@ -275,11 +310,15 @@ xrow_update_op_do_array_delete(struct xrow_update_op *op, struct xrow_update_field *field) { assert(field->type == XUPDATE_ARRAY); + if (xrow_update_op_prepare_num_token(op) != 0) + return -1; + if (!xrow_update_op_is_term(op)) { struct xrow_update_array_item *item = xrow_update_array_extract_item(field, op); if (item == NULL) return -1; + op->token_type = JSON_TOKEN_END; return xrow_update_op_do_field_delete(op, &item->field); } @@ -301,12 +340,16 @@ int \ xrow_update_op_do_array_##op_type(struct xrow_update_op *op, \ struct xrow_update_field *field) \ { \ + if (xrow_update_op_prepare_num_token(op) != 0) \ + return -1; \ struct xrow_update_array_item *item = \ xrow_update_array_extract_item(field, op); \ if (item == NULL) \ return -1; \ - if (!xrow_update_op_is_term(op)) \ + if (!xrow_update_op_is_term(op)) { \ + op->token_type = JSON_TOKEN_END; \ return xrow_update_op_do_field_##op_type(op, &item->field); \ + } \ if (item->field.type != XUPDATE_NOP) \ return xrow_update_err_double(op); \ if (xrow_update_op_do_##op_type(op, item->field.data) != 0) \ diff --git a/src/box/xrow_update_field.c b/src/box/xrow_update_field.c index de865a21d..96fcaf747 100644 --- a/src/box/xrow_update_field.c +++ b/src/box/xrow_update_field.c @@ -611,6 +611,22 @@ xrow_update_op_by(char opcode) } } +int +xrow_update_op_consume_token(struct xrow_update_op *op) +{ + struct json_token token; + int rc = json_lexer_next_token(&op->lexer, &token); + if (rc != 0) + return xrow_update_err_bad_json(op, rc); + if (token.type == JSON_TOKEN_END) + return xrow_update_err_no_such_field(op); + op->token_type = token.type; + op->key = token.str; + op->key_len = token.len; + op->field_no = token.num; + return 0; +} + int xrow_update_op_decode(struct xrow_update_op *op, int index_base, struct tuple_dictionary *dict, const char **expr) @@ -639,6 +655,12 @@ xrow_update_op_decode(struct xrow_update_op *op, int index_base, diag_set(ClientError, ER_UNKNOWN_UPDATE_OP); return -1; } + /* + * First token is always num. Even if a user specified a + * field name it is converted to num by the tuple + * dictionary. + */ + op->token_type = JSON_TOKEN_NUM; int32_t field_no = 0; switch(mp_typeof(**expr)) { case MP_INT: diff --git a/src/box/xrow_update_field.h b/src/box/xrow_update_field.h index bda9222cc..fbaf45c5d 100644 --- a/src/box/xrow_update_field.h +++ b/src/box/xrow_update_field.h @@ -179,8 +179,18 @@ struct xrow_update_op { const struct xrow_update_op_meta *meta; /** Operation arguments. */ union xrow_update_arg arg; - /** First level field no. */ - int32_t field_no; + /** + * Current level token. END means that it is invalid and + * a next token should be extracted from the lexer. + */ + enum json_token_type token_type; + union { + struct { + const char *key; + uint32_t key_len; + }; + int32_t field_no; + }; /** Size of a new field after it is updated. */ uint32_t new_field_len; /** Opcode symbol: = + - / ... */ @@ -193,6 +203,17 @@ struct xrow_update_op { struct json_lexer lexer; }; +/** + * Extract a next token from the operation path lexer. The result + * is used to decide to which child of a current map/array the + * operation should be forwarded. It is not just a synonym to + * json_lexer_next_token, because fills some fields of @a op, + * and should be used only to chose a next child inside a current + * map/array. + */ +int +xrow_update_op_consume_token(struct xrow_update_op *op); + /** * Decode an update operation from MessagePack. * @param[out] op Update operation. -- 2.21.0 (Apple Git-122.2)