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gerrit.cesnet.cz / github / CESNET / libyang / 63e080d0a25afc2a0e6d660b7abe97b596ead4a1 / . / src / diff.c
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/**
* @file diff.c
* @author Michal Vasko <mvasko@cesnet.cz>
* @brief diff functions
*
* Copyright (c) 2020 - 2021 CESNET, z.s.p.o.
*
* This source code is licensed under BSD 3-Clause License (the "License").
* You may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://opensource.org/licenses/BSD-3-Clause
*/
#define _GNU_SOURCE /* asprintf, strdup */
#include "diff.h"
#include <assert.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "common.h"
#include "compat.h"
#include "context.h"
#include "log.h"
#include "plugins_types.h"
#include "set.h"
#include "tree.h"
#include "tree_data.h"
#include "tree_data_internal.h"
#include "tree_edit.h"
#include "tree_schema.h"
#include "tree_schema_internal.h"
static const char *
lyd_diff_op2str(enum lyd_diff_op op)
{
switch (op) {
case LYD_DIFF_OP_CREATE:
return "create";
case LYD_DIFF_OP_DELETE:
return "delete";
case LYD_DIFF_OP_REPLACE:
return "replace";
case LYD_DIFF_OP_NONE:
return "none";
}
LOGINT(NULL);
return NULL;
}
static enum lyd_diff_op
lyd_diff_str2op(const char *str)
{
switch (str[0]) {
case 'c':
assert(!strcmp(str, "create"));
return LYD_DIFF_OP_CREATE;
case 'd':
assert(!strcmp(str, "delete"));
return LYD_DIFF_OP_DELETE;
case 'r':
assert(!strcmp(str, "replace"));
return LYD_DIFF_OP_REPLACE;
case 'n':
assert(!strcmp(str, "none"));
return LYD_DIFF_OP_NONE;
}
LOGINT(NULL);
return 0;
}
LY_ERR
lyd_diff_add(const struct lyd_node *node, enum lyd_diff_op op, const char *orig_default, const char *orig_value,
const char *key, const char *value, const char *position, const char *orig_key, const char *orig_position,
struct lyd_node **diff)
{
struct lyd_node *dup, *siblings, *match = NULL, *diff_parent = NULL;
const struct lyd_node *parent = NULL;
const struct lys_module *yang_mod;
assert(diff);
/* replace leaf always needs orig-default and orig-value */
assert((node->schema->nodetype != LYS_LEAF) || (op != LYD_DIFF_OP_REPLACE) || (orig_default && orig_value));
/* create on userord needs key/value */
assert((node->schema->nodetype != LYS_LIST) || !(node->schema->flags & LYS_ORDBY_USER) || (op != LYD_DIFF_OP_CREATE) ||
(lysc_is_dup_inst_list(node->schema) && position) || key);
assert((node->schema->nodetype != LYS_LEAFLIST) || !(node->schema->flags & LYS_ORDBY_USER) ||
(op != LYD_DIFF_OP_CREATE) || (lysc_is_dup_inst_list(node->schema) && position) || value);
/* move on userord needs both key and orig-key/value and orig-value */
assert((node->schema->nodetype != LYS_LIST) || !(node->schema->flags & LYS_ORDBY_USER) || (op != LYD_DIFF_OP_REPLACE) ||
(lysc_is_dup_inst_list(node->schema) && position && orig_position) || (key && orig_key));
assert((node->schema->nodetype != LYS_LEAFLIST) || !(node->schema->flags & LYS_ORDBY_USER) ||
(op != LYD_DIFF_OP_REPLACE) || (lysc_is_dup_inst_list(node->schema) && position && orig_position) ||
(value && orig_value));
/* find the first existing parent */
siblings = *diff;
while (1) {
/* find next node parent */
parent = node;
while (parent->parent && (!diff_parent || (parent->parent->schema != diff_parent->schema))) {
parent = lyd_parent(parent);
}
if (parent == node) {
/* no more parents to find */
break;
}
/* check whether it exists in the diff */
if (lyd_find_sibling_first(siblings, parent, &match)) {
break;
}
/* another parent found */
diff_parent = match;
/* move down in the diff */
siblings = lyd_child_no_keys(match);
}
/* duplicate the subtree (and connect to the diff if possible) */
LY_CHECK_RET(lyd_dup_single(node, (struct lyd_node_inner *)diff_parent,
LYD_DUP_RECURSIVE | LYD_DUP_NO_META | LYD_DUP_WITH_PARENTS | LYD_DUP_WITH_FLAGS, &dup));
/* find the first duplicated parent */
if (!diff_parent) {
diff_parent = lyd_parent(dup);
while (diff_parent && diff_parent->parent) {
diff_parent = lyd_parent(diff_parent);
}
} else {
diff_parent = dup;
while (diff_parent->parent && (diff_parent->parent->schema == parent->schema)) {
diff_parent = lyd_parent(diff_parent);
}
}
/* no parent existed, must be manually connected */
if (!diff_parent) {
/* there actually was no parent to duplicate */
lyd_insert_sibling(*diff, dup, diff);
} else if (!diff_parent->parent) {
lyd_insert_sibling(*diff, diff_parent, diff);
}
/* get module with the operation metadata */
yang_mod = LYD_CTX(node)->list.objs[1];
assert(!strcmp(yang_mod->name, "yang"));
/* add parent operation, if any */
if (diff_parent && (diff_parent != dup)) {
LY_CHECK_RET(lyd_new_meta(LYD_CTX(node), diff_parent, yang_mod, "operation", "none", 0, NULL));
}
/* add subtree operation */
LY_CHECK_RET(lyd_new_meta(LYD_CTX(node), dup, yang_mod, "operation", lyd_diff_op2str(op), 0, NULL));
/* orig-default */
if (orig_default) {
LY_CHECK_RET(lyd_new_meta(LYD_CTX(node), dup, yang_mod, "orig-default", orig_default, 0, NULL));
}
/* orig-value */
if (orig_value) {
LY_CHECK_RET(lyd_new_meta(LYD_CTX(node), dup, yang_mod, "orig-value", orig_value, 0, NULL));
}
/* key */
if (key) {
LY_CHECK_RET(lyd_new_meta(LYD_CTX(node), dup, yang_mod, "key", key, 0, NULL));
}
/* value */
if (value) {
LY_CHECK_RET(lyd_new_meta(LYD_CTX(node), dup, yang_mod, "value", value, 0, NULL));
}
/* position */
if (position) {
LY_CHECK_RET(lyd_new_meta(LYD_CTX(node), dup, yang_mod, "position", position, 0, NULL));
}
/* orig-key */
if (orig_key) {
LY_CHECK_RET(lyd_new_meta(LYD_CTX(node), dup, yang_mod, "orig-key", orig_key, 0, NULL));
}
/* orig-position */
if (orig_position) {
LY_CHECK_RET(lyd_new_meta(LYD_CTX(node), dup, yang_mod, "orig-position", orig_position, 0, NULL));
}
return LY_SUCCESS;
}
/**
* @brief Get a userord entry for a specific user-ordered list/leaf-list. Create if does not exist yet.
*
* @param[in] first Node from the first tree, can be NULL (on create).
* @param[in] schema Schema node of the list/leaf-list.
* @param[in,out] userord Sized array of userord items.
* @return Userord item for all the user-ordered list/leaf-list instances.
*/
static struct lyd_diff_userord *
lyd_diff_userord_get(const struct lyd_node *first, const struct lysc_node *schema, struct lyd_diff_userord **userord)
{
struct lyd_diff_userord *item;
struct lyd_node *iter;
const struct lyd_node **node;
LY_ARRAY_COUNT_TYPE u;
LY_ARRAY_FOR(*userord, u) {
if ((*userord)[u].schema == schema) {
return &(*userord)[u];
}
}
/* it was not added yet, add it now */
LY_ARRAY_NEW_RET(schema->module->ctx, *userord, item, NULL);
item->schema = schema;
item->pos = 0;
item->inst = NULL;
/* store all the instance pointers in the current order */
if (first) {
LYD_LIST_FOR_INST(lyd_first_sibling(first), first->schema, iter) {
LY_ARRAY_NEW_RET(schema->module->ctx, item->inst, node, NULL);
*node = iter;
}
}
return item;
}
/**
* @brief Get all the metadata to be stored in a diff for the 2 nodes. Can be used only for user-ordered
* lists/leaf-lists.
*
* @param[in] first Node from the first tree, can be NULL (on create).
* @param[in] second Node from the second tree, can be NULL (on delete).
* @param[in] options Diff options.
* @param[in,out] userord Sized array of userord items for keeping the current node order.
* @param[out] op Operation.
* @param[out] orig_default Original default metadata.
* @param[out] value Value metadata.
* @param[out] orig_value Original value metadata
* @param[out] key Key metadata.
* @param[out] orig_key Original key metadata.
* @param[out] position Position metadata.
* @param[out] orig_position Original position metadata.
* @return LY_SUCCESS on success,
* @return LY_ENOT if there is no change to be added into diff,
* @return LY_ERR value on other errors.
*/
static LY_ERR
lyd_diff_userord_attrs(const struct lyd_node *first, const struct lyd_node *second, uint16_t options,
struct lyd_diff_userord **userord, enum lyd_diff_op *op, const char **orig_default, char **value,
char **orig_value, char **key, char **orig_key, char **position, char **orig_position)
{
const struct lysc_node *schema;
size_t buflen, bufused;
uint32_t first_pos, second_pos;
struct lyd_diff_userord *userord_item;
assert(first || second);
*orig_default = NULL;
*value = NULL;
*orig_value = NULL;
*key = NULL;
*orig_key = NULL;
*position = NULL;
*orig_position = NULL;
schema = first ? first->schema : second->schema;
assert(lysc_is_userordered(schema));
/* get userord entry */
userord_item = lyd_diff_userord_get(first, schema, userord);
LY_CHECK_RET(!userord_item, LY_EMEM);
/* find user-ordered first position */
if (first) {
for (first_pos = 0; first_pos < LY_ARRAY_COUNT(userord_item->inst); ++first_pos) {
if (userord_item->inst[first_pos] == first) {
break;
}
}
assert(first_pos < LY_ARRAY_COUNT(userord_item->inst));
} else {
first_pos = 0;
}
/* prepare position of the next instance */
second_pos = userord_item->pos++;
/* learn operation first */
if (!second) {
*op = LYD_DIFF_OP_DELETE;
} else if (!first) {
*op = LYD_DIFF_OP_CREATE;
} else {
if (lyd_compare_single(second, userord_item->inst[second_pos], 0)) {
/* in first, there is a different instance on the second position, we are going to move 'first' node */
*op = LYD_DIFF_OP_REPLACE;
} else if ((options & LYD_DIFF_DEFAULTS) && ((first->flags & LYD_DEFAULT) != (second->flags & LYD_DEFAULT))) {
/* default flag change */
*op = LYD_DIFF_OP_NONE;
} else {
/* no changes */
return LY_ENOT;
}
}
/*
* set each attribute correctly based on the operation and node type
*/
/* orig-default */
if ((schema->nodetype == LYS_LEAFLIST) && ((*op == LYD_DIFF_OP_REPLACE) || (*op == LYD_DIFF_OP_NONE))) {
if (first->flags & LYD_DEFAULT) {
*orig_default = "true";
} else {
*orig_default = "false";
}
}
/* value */
if ((schema->nodetype == LYS_LEAFLIST) && !lysc_is_dup_inst_list(schema) &&
((*op == LYD_DIFF_OP_REPLACE) || (*op == LYD_DIFF_OP_CREATE))) {
if (second_pos) {
*value = strdup(lyd_get_value(userord_item->inst[second_pos - 1]));
LY_CHECK_ERR_RET(!*value, LOGMEM(schema->module->ctx), LY_EMEM);
} else {
*value = strdup("");
LY_CHECK_ERR_RET(!*value, LOGMEM(schema->module->ctx), LY_EMEM);
}
}
/* orig-value */
if ((schema->nodetype == LYS_LEAFLIST) && !lysc_is_dup_inst_list(schema) &&
((*op == LYD_DIFF_OP_REPLACE) || (*op == LYD_DIFF_OP_DELETE))) {
if (first_pos) {
*orig_value = strdup(lyd_get_value(userord_item->inst[first_pos - 1]));
LY_CHECK_ERR_RET(!*orig_value, LOGMEM(schema->module->ctx), LY_EMEM);
} else {
*orig_value = strdup("");
LY_CHECK_ERR_RET(!*orig_value, LOGMEM(schema->module->ctx), LY_EMEM);
}
}
/* key */
if ((schema->nodetype == LYS_LIST) && !lysc_is_dup_inst_list(schema) &&
((*op == LYD_DIFF_OP_REPLACE) || (*op == LYD_DIFF_OP_CREATE))) {
if (second_pos) {
buflen = bufused = 0;
LY_CHECK_RET(lyd_path_list_predicate(userord_item->inst[second_pos - 1], key, &buflen, &bufused, 0));
} else {
*key = strdup("");
LY_CHECK_ERR_RET(!*key, LOGMEM(schema->module->ctx), LY_EMEM);
}
}
/* orig-key */
if ((schema->nodetype == LYS_LIST) && !lysc_is_dup_inst_list(schema) &&
((*op == LYD_DIFF_OP_REPLACE) || (*op == LYD_DIFF_OP_DELETE))) {
if (first_pos) {
buflen = bufused = 0;
LY_CHECK_RET(lyd_path_list_predicate(userord_item->inst[first_pos - 1], orig_key, &buflen, &bufused, 0));
} else {
*orig_key = strdup("");
LY_CHECK_ERR_RET(!*orig_key, LOGMEM(schema->module->ctx), LY_EMEM);
}
}
/* position */
if (lysc_is_dup_inst_list(schema) && ((*op == LYD_DIFF_OP_REPLACE) || (*op == LYD_DIFF_OP_CREATE))) {
if (second_pos) {
if (asprintf(position, "%" PRIu32, second_pos) == -1) {
LOGMEM(schema->module->ctx);
return LY_EMEM;
}
} else {
*position = strdup("");
LY_CHECK_ERR_RET(!*position, LOGMEM(schema->module->ctx), LY_EMEM);
}
}
/* orig-position */
if (lysc_is_dup_inst_list(schema) && ((*op == LYD_DIFF_OP_REPLACE) || (*op == LYD_DIFF_OP_DELETE))) {
if (first_pos) {
if (asprintf(orig_position, "%" PRIu32, first_pos) == -1) {
LOGMEM(schema->module->ctx);
return LY_EMEM;
}
} else {
*orig_position = strdup("");
LY_CHECK_ERR_RET(!*orig_position, LOGMEM(schema->module->ctx), LY_EMEM);
}
}
/*
* update our instances - apply the change
*/
if (*op == LYD_DIFF_OP_CREATE) {
/* insert the instance */
LY_ARRAY_CREATE_RET(schema->module->ctx, userord_item->inst, 1, LY_EMEM);
if (second_pos < LY_ARRAY_COUNT(userord_item->inst)) {
memmove(userord_item->inst + second_pos + 1, userord_item->inst + second_pos,
(LY_ARRAY_COUNT(userord_item->inst) - second_pos) * sizeof *userord_item->inst);
}
LY_ARRAY_INCREMENT(userord_item->inst);
userord_item->inst[second_pos] = second;
} else if (*op == LYD_DIFF_OP_DELETE) {
/* remove the instance */
if (first_pos + 1 < LY_ARRAY_COUNT(userord_item->inst)) {
memmove(userord_item->inst + first_pos, userord_item->inst + first_pos + 1,
(LY_ARRAY_COUNT(userord_item->inst) - first_pos - 1) * sizeof *userord_item->inst);
}
LY_ARRAY_DECREMENT(userord_item->inst);
} else if (*op == LYD_DIFF_OP_REPLACE) {
/* move the instances */
memmove(userord_item->inst + second_pos + 1, userord_item->inst + second_pos,
(first_pos - second_pos) * sizeof *userord_item->inst);
userord_item->inst[second_pos] = first;
}
return LY_SUCCESS;
}
/**
* @brief Get all the metadata to be stored in a diff for the 2 nodes. Cannot be used for user-ordered
* lists/leaf-lists.
*
* @param[in] first Node from the first tree, can be NULL (on create).
* @param[in] second Node from the second tree, can be NULL (on delete).
* @param[in] options Diff options.
* @param[out] op Operation.
* @param[out] orig_default Original default metadata.
* @param[out] orig_value Original value metadata.
* @return LY_SUCCESS on success,
* @return LY_ENOT if there is no change to be added into diff,
* @return LY_ERR value on other errors.
*/
static LY_ERR
lyd_diff_attrs(const struct lyd_node *first, const struct lyd_node *second, uint16_t options, enum lyd_diff_op *op,
const char **orig_default, char **orig_value)
{
const struct lysc_node *schema;
assert(first || second);
*orig_default = NULL;
*orig_value = NULL;
schema = first ? first->schema : second->schema;
assert(!lysc_is_userordered(schema));
/* learn operation first */
if (!second) {
*op = LYD_DIFF_OP_DELETE;
} else if (!first) {
*op = LYD_DIFF_OP_CREATE;
} else {
switch (schema->nodetype) {
case LYS_CONTAINER:
case LYS_RPC:
case LYS_ACTION:
case LYS_NOTIF:
/* no changes */
return LY_ENOT;
case LYS_LIST:
case LYS_LEAFLIST:
if ((options & LYD_DIFF_DEFAULTS) && ((first->flags & LYD_DEFAULT) != (second->flags & LYD_DEFAULT))) {
/* default flag change */
*op = LYD_DIFF_OP_NONE;
} else {
/* no changes */
return LY_ENOT;
}
break;
case LYS_LEAF:
case LYS_ANYXML:
case LYS_ANYDATA:
if (lyd_compare_single(first, second, 0)) {
/* different values */
*op = LYD_DIFF_OP_REPLACE;
} else if ((options & LYD_DIFF_DEFAULTS) && ((first->flags & LYD_DEFAULT) != (second->flags & LYD_DEFAULT))) {
/* default flag change */
*op = LYD_DIFF_OP_NONE;
} else {
/* no changes */
return LY_ENOT;
}
break;
default:
LOGINT_RET(schema->module->ctx);
}
}
/*
* set each attribute correctly based on the operation and node type
*/
/* orig-default */
if ((schema->nodetype & LYD_NODE_TERM) && ((*op == LYD_DIFF_OP_REPLACE) || (*op == LYD_DIFF_OP_NONE))) {
if (first->flags & LYD_DEFAULT) {
*orig_default = "true";
} else {
*orig_default = "false";
}
}
/* orig-value */
if ((schema->nodetype & (LYS_LEAF | LYS_ANYDATA)) && (*op == LYD_DIFF_OP_REPLACE)) {
if (schema->nodetype == LYS_LEAF) {
*orig_value = strdup(lyd_get_value(first));
LY_CHECK_ERR_RET(!*orig_value, LOGMEM(schema->module->ctx), LY_EMEM);
} else {
LY_CHECK_RET(lyd_any_value_str(first, orig_value));
}
}
return LY_SUCCESS;
}
/**
* @brief Find a matching instance of a node in a data tree.
*
* @param[in] siblings Siblings to search in.
* @param[in] target Target node to search for.
* @param[in] defaults Whether to consider (or ignore) default values.
* @param[in,out] dup_inst_cache Duplicate instance cache.
* @param[out] match Found match, NULL if no matching node found.
* @return LY_ERR value.
*/
static LY_ERR
lyd_diff_find_match(const struct lyd_node *siblings, const struct lyd_node *target, ly_bool defaults,
struct lyd_dup_inst **dup_inst_cache, struct lyd_node **match)
{
if (target->schema->nodetype & (LYS_LIST | LYS_LEAFLIST)) {
/* try to find the exact instance */
lyd_find_sibling_first(siblings, target, match);
} else {
/* try to simply find the node, there cannot be more instances */
lyd_find_sibling_val(siblings, target->schema, NULL, 0, match);
}
/* update match as needed */
LY_CHECK_RET(lyd_dup_inst_next(match, siblings, dup_inst_cache));
if (*match && ((*match)->flags & LYD_DEFAULT) && !defaults) {
/* ignore default nodes */
*match = NULL;
}
return LY_SUCCESS;
}
/**
* @brief Perform diff for all siblings at certain depth, recursively.
*
* For user-ordered lists/leaf-lists a specific structure is used for storing
* the current order. The idea is to apply all the generated diff changes
* virtually on the first tree so that we can continue to generate correct
* changes after some were already generated.
*
* The algorithm then uses second tree position-based changes with a before
* (preceding) item anchor.
*
* Example:
*
* Virtual first tree leaf-list order:
* 1 2 [3] 4 5
*
* Second tree leaf-list order:
* 1 2 [5] 3 4
*
* We are at the 3rd node now. We look at whether the nodes on the 3rd position
* match - they do not - move nodes so that the 3rd position node is final ->
* -> move node 5 to the 3rd position -> move node 5 after node 2.
*
* Required properties:
* Stored operations (move) should not be affected by later operations -
* - would cause a redundantly long list of operations, possibly inifinite.
*
* Implemenation justification:
* First, all delete operations and only then move/create operations are stored.
* Also, preceding anchor is used and after each iteration another node is
* at its final position. That results in the invariant that all preceding
* nodes are final and will not be changed by the later operations, meaning
* they can safely be used as anchors for the later operations.
*
* @param[in] first First tree first sibling.
* @param[in] second Second tree first sibling.
* @param[in] options Diff options.
* @param[in] nosiblings Whether to skip following siblings.
* @param[in,out] diff Diff to append to.
* @return LY_ERR value.
*/
static LY_ERR
lyd_diff_siblings_r(const struct lyd_node *first, const struct lyd_node *second, uint16_t options, ly_bool nosiblings,
struct lyd_node **diff)
{
LY_ERR ret = LY_SUCCESS;
const struct lyd_node *iter_first, *iter_second;
struct lyd_node *match_second, *match_first;
struct lyd_diff_userord *userord = NULL;
struct lyd_dup_inst *dup_inst_first = NULL, *dup_inst_second = NULL;
LY_ARRAY_COUNT_TYPE u;
enum lyd_diff_op op;
const char *orig_default;
char *orig_value, *key, *value, *position, *orig_key, *orig_position;
/* compare first tree to the second tree - delete, replace, none */
LY_LIST_FOR(first, iter_first) {
assert(!(iter_first->schema->flags & LYS_KEY));
if ((iter_first->flags & LYD_DEFAULT) && !(options & LYD_DIFF_DEFAULTS)) {
/* skip default nodes */
continue;
}
/* find a match in the second tree */
LY_CHECK_GOTO(ret = lyd_diff_find_match(second, iter_first, options & LYD_DIFF_DEFAULTS, &dup_inst_second,
&match_second), cleanup);
if (lysc_is_userordered(iter_first->schema)) {
/* we are handling only user-ordered node delete now */
if (!match_second) {
/* get all the attributes */
LY_CHECK_GOTO(ret = lyd_diff_userord_attrs(iter_first, match_second, options, &userord, &op, &orig_default,
&value, &orig_value, &key, &orig_key, &position, &orig_position), cleanup);
/* there must be changes, it is deleted */
assert(op == LYD_DIFF_OP_DELETE);
ret = lyd_diff_add(iter_first, op, orig_default, orig_value, key, value, position, orig_key, orig_position, diff);
free(orig_value);
free(key);
free(value);
free(position);
free(orig_key);
free(orig_position);
LY_CHECK_GOTO(ret, cleanup);
}
} else {
/* get all the attributes */
ret = lyd_diff_attrs(iter_first, match_second, options, &op, &orig_default, &orig_value);
/* add into diff if there are any changes */
if (!ret) {
if (op == LYD_DIFF_OP_DELETE) {
ret = lyd_diff_add(iter_first, op, orig_default, orig_value, NULL, NULL, NULL, NULL, NULL, diff);
} else {
assert(match_second);
ret = lyd_diff_add(match_second, op, orig_default, orig_value, NULL, NULL, NULL, NULL, NULL, diff);
}
free(orig_value);
LY_CHECK_GOTO(ret, cleanup);
} else if (ret == LY_ENOT) {
ret = LY_SUCCESS;
} else {
goto cleanup;
}
}
/* check descendants, if any, recursively */
if (match_second) {
LY_CHECK_GOTO(ret = lyd_diff_siblings_r(lyd_child_no_keys(iter_first), lyd_child_no_keys(match_second),
options, 0, diff), cleanup);
}
if (nosiblings) {
break;
}
}
/* reset all cached positions */
LY_ARRAY_FOR(userord, u) {
userord[u].pos = 0;
}
/* compare second tree to the first tree - create, user-ordered move */
LY_LIST_FOR(second, iter_second) {
assert(!(iter_second->schema->flags & LYS_KEY));
if ((iter_second->flags & LYD_DEFAULT) && !(options & LYD_DIFF_DEFAULTS)) {
/* skip default nodes */
continue;
}
/* find a match in the first tree */
LY_CHECK_GOTO(ret = lyd_diff_find_match(first, iter_second, options & LYD_DIFF_DEFAULTS, &dup_inst_first,
&match_first), cleanup);
if (lysc_is_userordered(iter_second->schema)) {
/* get all the attributes */
ret = lyd_diff_userord_attrs(match_first, iter_second, options, &userord, &op, &orig_default,
&value, &orig_value, &key, &orig_key, &position, &orig_position);
/* add into diff if there are any changes */
if (!ret) {
ret = lyd_diff_add(iter_second, op, orig_default, orig_value, key, value, position, orig_key,
orig_position, diff);
free(orig_value);
free(key);
free(value);
free(position);
free(orig_key);
free(orig_position);
LY_CHECK_GOTO(ret, cleanup);
} else if (ret == LY_ENOT) {
ret = LY_SUCCESS;
} else {
goto cleanup;
}
} else if (!match_first) {
/* get all the attributes */
LY_CHECK_GOTO(ret = lyd_diff_attrs(match_first, iter_second, options, &op, &orig_default, &orig_value), cleanup);
/* there must be changes, it is created */
assert(op == LYD_DIFF_OP_CREATE);
ret = lyd_diff_add(iter_second, op, orig_default, orig_value, NULL, NULL, NULL, NULL, NULL, diff);
free(orig_value);
LY_CHECK_GOTO(ret, cleanup);
} /* else was handled */
if (nosiblings) {
break;
}
}
cleanup:
lyd_dup_inst_free(dup_inst_first);
lyd_dup_inst_free(dup_inst_second);
LY_ARRAY_FOR(userord, u) {
LY_ARRAY_FREE(userord[u].inst);
}
LY_ARRAY_FREE(userord);
return ret;
}
static LY_ERR
lyd_diff(const struct lyd_node *first, const struct lyd_node *second, uint16_t options, ly_bool nosiblings, struct lyd_node **diff)
{
const struct ly_ctx *ctx;
LY_CHECK_ARG_RET(NULL, diff, LY_EINVAL);
if (first) {
ctx = LYD_CTX(first);
} else if (second) {
ctx = LYD_CTX(second);
} else {
ctx = NULL;
}
if (first && second && (lysc_data_parent(first->schema) != lysc_data_parent(second->schema))) {
LOGERR(ctx, LY_EINVAL, "Invalid arguments - cannot create diff for unrelated data (%s()).", __func__);
return LY_EINVAL;
}
*diff = NULL;
return lyd_diff_siblings_r(first, second, options, nosiblings, diff);
}
API LY_ERR
lyd_diff_tree(const struct lyd_node *first, const struct lyd_node *second, uint16_t options, struct lyd_node **diff)
{
return lyd_diff(first, second, options, 1, diff);
}
API LY_ERR
lyd_diff_siblings(const struct lyd_node *first, const struct lyd_node *second, uint16_t options, struct lyd_node **diff)
{
return lyd_diff(first, second, options, 0, diff);
}
/**
* @brief Learn operation of a diff node.
*
* @param[in] diff_node Diff node.
* @param[out] op Operation.
* @return LY_ERR value.
*/
static LY_ERR
lyd_diff_get_op(const struct lyd_node *diff_node, enum lyd_diff_op *op)
{
struct lyd_meta *meta = NULL;
const struct lyd_node *diff_parent;
const char *str;
for (diff_parent = diff_node; diff_parent; diff_parent = lyd_parent(diff_parent)) {
LY_LIST_FOR(diff_parent->meta, meta) {
if (!strcmp(meta->name, "operation") && !strcmp(meta->annotation->module->name, "yang")) {
str = lyd_get_meta_value(meta);
if ((str[0] == 'r') && (diff_parent != diff_node)) {
/* we do not care about this operation if it's in our parent */
continue;
}
*op = lyd_diff_str2op(str);
break;
}
}
if (meta) {
break;
}
}
LY_CHECK_ERR_RET(!meta, LOGINT(LYD_CTX(diff_node)), LY_EINT);
return LY_SUCCESS;
}
/**
* @brief Insert a diff node into a data tree.
*
* @param[in,out] first_node First sibling of the data tree.
* @param[in] parent_node Data tree sibling parent node.
* @param[in] new_node Node to insert.
* @param[in] userord_anchor Optional anchor (key, value, or position) of relative (leaf-)list instance. If not set,
* the user-ordered instance will be inserted at the first position.
* @return err_info, NULL on success.
*/
static LY_ERR
lyd_diff_insert(struct lyd_node **first_node, struct lyd_node *parent_node, struct lyd_node *new_node,
const char *userord_anchor)
{
LY_ERR ret;
struct lyd_node *anchor;
uint32_t pos, anchor_pos;
int found;
assert(new_node);
if (!*first_node) {
if (!parent_node) {
/* no parent or siblings */
*first_node = new_node;
return LY_SUCCESS;
}
/* simply insert into parent, no other children */
if (userord_anchor) {
LOGERR(LYD_CTX(new_node), LY_EINVAL, "Node \"%s\" instance to insert next to not found.",
new_node->schema->name);
return LY_EINVAL;
}
return lyd_insert_child(parent_node, new_node);
}
assert(!(*first_node)->parent || (lyd_parent(*first_node) == parent_node));
if (!lysc_is_userordered(new_node->schema)) {
/* simple insert */
return lyd_insert_sibling(*first_node, new_node, first_node);
}
if (userord_anchor) {
/* find the anchor sibling */
if (lysc_is_dup_inst_list(new_node->schema)) {
anchor_pos = atoi(userord_anchor);
LY_CHECK_ERR_RET(!anchor_pos, LOGINT(LYD_CTX(new_node)), LY_EINT);
found = 0;
pos = 1;
LYD_LIST_FOR_INST(*first_node, new_node->schema, anchor) {
if (pos == anchor_pos) {
found = 1;
break;
}
++pos;
}
if (!found) {
LOGERR(LYD_CTX(new_node), LY_EINVAL, "Node \"%s\" instance to insert next to not found.",
new_node->schema->name);
return LY_EINVAL;
}
} else {
ret = lyd_find_sibling_val(*first_node, new_node->schema, userord_anchor, 0, &anchor);
if (ret == LY_ENOTFOUND) {
LOGERR(LYD_CTX(new_node), LY_EINVAL, "Node \"%s\" instance to insert next to not found.",
new_node->schema->name);
return LY_EINVAL;
} else if (ret) {
return ret;
}
}
/* insert after */
LY_CHECK_RET(lyd_insert_after(anchor, new_node));
assert(new_node->prev == anchor);
if (*first_node == new_node) {
*first_node = anchor;
}
} else {
if ((*first_node)->schema->flags & LYS_KEY) {
assert(parent_node && (parent_node->schema->nodetype == LYS_LIST));
/* find last key */
anchor = *first_node;
while (anchor->next && (anchor->next->schema->flags & LYS_KEY)) {
anchor = anchor->next;
}
/* insert after the last key */
LY_CHECK_RET(lyd_insert_after(anchor, new_node));
} else {
/* insert at the beginning */
LY_CHECK_RET(lyd_insert_before(*first_node, new_node));
*first_node = new_node;
}
}
return LY_SUCCESS;
}
/**
* @brief Apply diff subtree on data tree nodes, recursively.
*
* @param[in,out] first_node First sibling of the data tree.
* @param[in] parent_node Parent of the first sibling.
* @param[in] diff_node Current diff node.
* @param[in] diff_cb Optional diff callback.
* @param[in] cb_data User data for @p diff_cb.
* @param[in,out] dup_inst Duplicate instance cache for all @p diff_node siblings.
* @return LY_ERR value.
*/
static LY_ERR
lyd_diff_apply_r(struct lyd_node **first_node, struct lyd_node *parent_node, const struct lyd_node *diff_node,
lyd_diff_cb diff_cb, void *cb_data, struct lyd_dup_inst **dup_inst)
{
LY_ERR ret;
struct lyd_node *match, *diff_child;
const char *str_val, *meta_str;
enum lyd_diff_op op;
struct lyd_meta *meta;
struct lyd_dup_inst *child_dup_inst = NULL;
const struct ly_ctx *ctx = LYD_CTX(diff_node);
/* read all the valid attributes */
LY_CHECK_RET(lyd_diff_get_op(diff_node, &op));
/* handle specific user-ordered (leaf-)lists operations separately */
if (lysc_is_userordered(diff_node->schema) && ((op == LYD_DIFF_OP_CREATE) || (op == LYD_DIFF_OP_REPLACE))) {
if (op == LYD_DIFF_OP_REPLACE) {
/* find the node (we must have some siblings because the node was only moved) */
LY_CHECK_RET(lyd_diff_find_match(*first_node, diff_node, 1, dup_inst, &match));
LY_CHECK_ERR_RET(!match, LOGINT(ctx), LY_EINT);
} else {
/* duplicate the node */
LY_CHECK_RET(lyd_dup_single(diff_node, NULL, LYD_DUP_NO_META, &match));
}
/* get "key", "value", or "position" metadata string value */
if (lysc_is_dup_inst_list(diff_node->schema)) {
meta_str = "yang:position";
} else if (diff_node->schema->nodetype == LYS_LIST) {
meta_str = "yang:key";
} else {
meta_str = "yang:value";
}
meta = lyd_find_meta(diff_node->meta, NULL, meta_str);
LY_CHECK_ERR_RET(!meta, LOGINT(ctx), LY_EINT);
str_val = lyd_get_meta_value(meta);
/* insert/move the node */
if (str_val[0]) {
ret = lyd_diff_insert(first_node, parent_node, match, str_val);
} else {
ret = lyd_diff_insert(first_node, parent_node, match, NULL);
}
if (ret) {
if (op == LYD_DIFF_OP_CREATE) {
lyd_free_tree(match);
}
return ret;
}
goto next_iter_r;
}
/* apply operation */
switch (op) {
case LYD_DIFF_OP_NONE:
/* find the node */
LY_CHECK_RET(lyd_diff_find_match(*first_node, diff_node, 1, dup_inst, &match));
LY_CHECK_ERR_RET(!match, LOGINT(ctx), LY_EINT);
if (match->schema->nodetype & LYD_NODE_TERM) {
/* special case of only dflt flag change */
if (diff_node->flags & LYD_DEFAULT) {
match->flags |= LYD_DEFAULT;
} else {
match->flags &= ~LYD_DEFAULT;
}
} else {
/* none operation on nodes without children is redundant and hence forbidden */
if (!lyd_child_no_keys(diff_node)) {
LOGINT_RET(ctx);
}
}
break;
case LYD_DIFF_OP_CREATE:
/* duplicate the node */
LY_CHECK_RET(lyd_dup_single(diff_node, NULL, LYD_DUP_NO_META, &match));
/* insert it at the end */
ret = 0;
if (parent_node) {
ret = lyd_insert_child(parent_node, match);
} else {
ret = lyd_insert_sibling(*first_node, match, first_node);
}
if (ret) {
lyd_free_tree(match);
return ret;
}
break;
case LYD_DIFF_OP_DELETE:
/* find the node */
LY_CHECK_RET(lyd_diff_find_match(*first_node, diff_node, 1, dup_inst, &match));
LY_CHECK_ERR_RET(!match, LOGINT(ctx), LY_EINT);
/* remove it */
if ((match == *first_node) && !match->parent) {
assert(!parent_node);
/* we have removed the top-level node */
*first_node = (*first_node)->next;
}
lyd_free_tree(match);
/* we are not going recursively in this case, the whole subtree was already deleted */
return LY_SUCCESS;
case LYD_DIFF_OP_REPLACE:
LY_CHECK_ERR_RET(!(diff_node->schema->nodetype & (LYS_LEAF | LYS_ANYDATA)), LOGINT(ctx), LY_EINT);
/* find the node */
LY_CHECK_RET(lyd_diff_find_match(*first_node, diff_node, 1, dup_inst, &match));
LY_CHECK_ERR_RET(!match, LOGINT(ctx), LY_EINT);
/* update the value */
if (diff_node->schema->nodetype == LYS_LEAF) {
ret = lyd_change_term(match, lyd_get_value(diff_node));
if (ret && (ret != LY_EEXIST)) {
LOGINT_RET(ctx);
}
} else {
struct lyd_node_any *any = (struct lyd_node_any *)diff_node;
LY_CHECK_RET(lyd_any_copy_value(match, &any->value, any->value_type));
}
/* with flags */
match->flags = diff_node->flags;
break;
default:
LOGINT_RET(ctx);
}
next_iter_r:
if (diff_cb) {
/* call callback */
LY_CHECK_RET(diff_cb(diff_node, match, cb_data));
}
/* apply diff recursively */
ret = LY_SUCCESS;
LY_LIST_FOR(lyd_child_no_keys(diff_node), diff_child) {
ret = lyd_diff_apply_r(lyd_node_child_p(match), match, diff_child, diff_cb, cb_data, &child_dup_inst);
if (ret) {
break;
}
}
lyd_dup_inst_free(child_dup_inst);
return ret;
}
API LY_ERR
lyd_diff_apply_module(struct lyd_node **data, const struct lyd_node *diff, const struct lys_module *mod,
lyd_diff_cb diff_cb, void *cb_data)
{
const struct lyd_node *root;
struct lyd_dup_inst *dup_inst = NULL;
LY_ERR ret = LY_SUCCESS;
LY_LIST_FOR(diff, root) {
if (mod && (lyd_owner_module(root) != mod)) {
/* skip data nodes from different modules */
continue;
}
/* apply relevant nodes from the diff datatree */
ret = lyd_diff_apply_r(data, NULL, root, diff_cb, cb_data, &dup_inst);
if (ret) {
break;
}
}
lyd_dup_inst_free(dup_inst);
return ret;
}
API LY_ERR
lyd_diff_apply_all(struct lyd_node **data, const struct lyd_node *diff)
{
return lyd_diff_apply_module(data, diff, NULL, NULL, NULL);
}
/**
* @brief Update operations on a diff node when the new operation is NONE.
*
* @param[in] diff_match Node from the diff.
* @param[in] cur_op Current operation of @p diff_match.
* @param[in] src_diff Current source diff node.
* @return LY_ERR value.
*/
static LY_ERR
lyd_diff_merge_none(struct lyd_node *diff_match, enum lyd_diff_op cur_op, const struct lyd_node *src_diff)
{
switch (cur_op) {
case LYD_DIFF_OP_NONE:
case LYD_DIFF_OP_CREATE:
case LYD_DIFF_OP_REPLACE:
if (src_diff->schema->nodetype & LYD_NODE_TERM) {
/* NONE on a term means only its dflt flag was changed */
diff_match->flags &= ~LYD_DEFAULT;
diff_match->flags |= src_diff->flags & LYD_DEFAULT;
}
break;
default:
/* delete operation is not valid */
LOGINT_RET(LYD_CTX(src_diff));
}
return LY_SUCCESS;
}
/**
* @brief Remove an attribute from a node.
*
* @param[in] node Node with the metadata.
* @param[in] name Metadata name.
*/
static void
lyd_diff_del_meta(struct lyd_node *node, const char *name)
{
struct lyd_meta *meta;
LY_LIST_FOR(node->meta, meta) {
if (!strcmp(meta->name, name) && !strcmp(meta->annotation->module->name, "yang")) {
lyd_free_meta_single(meta);
return;
}
}
assert(0);
}
/**
* @brief Set a specific operation of a node. Delete the previous operation, if any.
* Does not change the default flag.
*
* @param[in] node Node to change.
* @param[in] op Operation to set.
* @return LY_ERR value.
*/
static LY_ERR
lyd_diff_change_op(struct lyd_node *node, enum lyd_diff_op op)
{
struct lyd_meta *meta;
LY_LIST_FOR(node->meta, meta) {
if (!strcmp(meta->name, "operation") && !strcmp(meta->annotation->module->name, "yang")) {
lyd_free_meta_single(meta);
break;
}
}
return lyd_new_meta(LYD_CTX(node), node, NULL, "yang:operation", lyd_diff_op2str(op), 0, NULL);
}
/**
* @brief Update operations on a diff node when the new operation is REPLACE.
*
* @param[in] diff_match Node from the diff.
* @param[in] cur_op Current operation of @p diff_match.
* @param[in] src_diff Current source diff node.
* @return LY_ERR value.
*/
static LY_ERR
lyd_diff_merge_replace(struct lyd_node *diff_match, enum lyd_diff_op cur_op, const struct lyd_node *src_diff)
{
LY_ERR ret;
const char *str_val, *meta_name, *orig_meta_name;
struct lyd_meta *meta;
const struct lys_module *mod;
const struct lyd_node_any *any;
/* get "yang" module for the metadata */
mod = ly_ctx_get_module_latest(LYD_CTX(diff_match), "yang");
assert(mod);
switch (cur_op) {
case LYD_DIFF_OP_REPLACE:
case LYD_DIFF_OP_CREATE:
switch (diff_match->schema->nodetype) {
case LYS_LIST:
case LYS_LEAFLIST:
/* it was created/moved somewhere, but now it will be created/moved somewhere else,
* keep orig_key/orig_value (only replace oper) and replace key/value */
assert(lysc_is_userordered(diff_match->schema));
if (lysc_is_dup_inst_list(diff_match->schema)) {
meta_name = "position";
} else if (diff_match->schema->nodetype == LYS_LIST) {
meta_name = "key";
} else {
meta_name = "value";
}
lyd_diff_del_meta(diff_match, meta_name);
meta = lyd_find_meta(src_diff->meta, mod, meta_name);
LY_CHECK_ERR_RET(!meta, LOGINT(LYD_CTX(src_diff)), LY_EINT);
LY_CHECK_RET(lyd_dup_meta_single(meta, diff_match, NULL));
break;
case LYS_LEAF:
/* replaced with the exact same value, impossible */
if (!lyd_compare_single(diff_match, src_diff, 0)) {
LOGINT_RET(LYD_CTX(src_diff));
}
/* modify the node value */
if (lyd_change_term(diff_match, lyd_get_value(src_diff))) {
LOGINT_RET(LYD_CTX(src_diff));
}
if (cur_op == LYD_DIFF_OP_REPLACE) {
/* compare values whether there is any change at all */
meta = lyd_find_meta(diff_match->meta, mod, "orig-value");
LY_CHECK_ERR_RET(!meta, LOGINT(LYD_CTX(diff_match)), LY_EINT);
str_val = lyd_get_meta_value(meta);
ret = lyd_value_compare((struct lyd_node_term *)diff_match, str_val, strlen(str_val));
if (!ret) {
/* values are the same, remove orig-value meta and set oper to NONE */
lyd_free_meta_single(meta);
LY_CHECK_RET(lyd_diff_change_op(diff_match, LYD_DIFF_OP_NONE));
}
}
/* modify the default flag */
diff_match->flags &= ~LYD_DEFAULT;
diff_match->flags |= src_diff->flags & LYD_DEFAULT;
break;
case LYS_ANYXML:
case LYS_ANYDATA:
if (!lyd_compare_single(diff_match, src_diff, 0)) {
/* replaced with the exact same value, impossible */
LOGINT_RET(LYD_CTX(src_diff));
}
/* modify the node value */
any = (struct lyd_node_any *)src_diff;
LY_CHECK_RET(lyd_any_copy_value(diff_match, &any->value, any->value_type));
break;
default:
LOGINT_RET(LYD_CTX(src_diff));
}
break;
case LYD_DIFF_OP_NONE:
/* it is moved now */
assert(lysc_is_userordered(diff_match->schema) && (diff_match->schema->nodetype == LYS_LIST));
/* change the operation */
LY_CHECK_RET(lyd_diff_change_op(diff_match, LYD_DIFF_OP_REPLACE));
/* set orig-meta and meta */
if (lysc_is_dup_inst_list(diff_match->schema)) {
meta_name = "position";
orig_meta_name = "orig-position";
} else {
meta_name = "key";
orig_meta_name = "orig-key";
}
meta = lyd_find_meta(src_diff->meta, mod, orig_meta_name);
LY_CHECK_ERR_RET(!meta, LOGINT(LYD_CTX(src_diff)), LY_EINT);
LY_CHECK_RET(lyd_dup_meta_single(meta, diff_match, NULL));
meta = lyd_find_meta(src_diff->meta, mod, meta_name);
LY_CHECK_ERR_RET(!meta, LOGINT(LYD_CTX(src_diff)), LY_EINT);
LY_CHECK_RET(lyd_dup_meta_single(meta, diff_match, NULL));
break;
default:
/* delete operation is not valid */
LOGINT_RET(LYD_CTX(src_diff));
}
return LY_SUCCESS;
}
/**
* @brief Update operations in a diff node when the new operation is CREATE.
*
* @param[in] diff_match Node from the diff.
* @param[in] cur_op Current operation of @p diff_match.
* @param[in] src_diff Current source diff node.
* @param[in] options Diff merge options.
* @return LY_ERR value.
*/
static LY_ERR
lyd_diff_merge_create(struct lyd_node *diff_match, enum lyd_diff_op cur_op, const struct lyd_node *src_diff, uint16_t options)
{
struct lyd_node *child;
const struct lysc_node_leaf *sleaf = NULL;
uint32_t trg_flags;
const char *meta_name, *orig_meta_name;
struct lyd_meta *meta, *orig_meta;
switch (cur_op) {
case LYD_DIFF_OP_DELETE:
/* remember current flags */
trg_flags = diff_match->flags;
if (lysc_is_userordered(diff_match->schema)) {
/* get anchor metadata */
if (lysc_is_dup_inst_list(diff_match->schema)) {
meta_name = "yang:position";
orig_meta_name = "yang:orig-position";
} else if (diff_match->schema->nodetype == LYS_LIST) {
meta_name = "yang:key";
orig_meta_name = "yang:orig-key";
} else {
meta_name = "yang:value";
orig_meta_name = "yang:orig-value";
}
meta = lyd_find_meta(src_diff->meta, NULL, meta_name);
orig_meta = lyd_find_meta(diff_match->meta, NULL, orig_meta_name);
LY_CHECK_ERR_RET(!meta || !orig_meta, LOGINT(LYD_CTX(src_diff)), LY_EINT);
/* the (incorrect) assumption made here is that there are no previous diff nodes that would affect
* the anchors stored in the metadata */
if (strcmp(lyd_get_meta_value(meta), lyd_get_meta_value(orig_meta))) {
/* deleted + created at another position -> operation REPLACE */
LY_CHECK_RET(lyd_diff_change_op(diff_match, LYD_DIFF_OP_REPLACE));
/* add anchor metadata */
LY_CHECK_RET(lyd_dup_meta_single(meta, diff_match, NULL));
} else {
/* deleted + created at the same position -> operation NONE */
LY_CHECK_RET(lyd_diff_change_op(diff_match, LYD_DIFF_OP_NONE));
/* delete anchor metadata */
lyd_free_meta_single(orig_meta);
}
} else if (diff_match->schema->nodetype == LYS_LEAF) {
if (options & LYD_DIFF_MERGE_DEFAULTS) {
/* we are dealing with a leaf and are handling default values specially (as explicit nodes) */
sleaf = (struct lysc_node_leaf *)diff_match->schema;
}
if (sleaf && sleaf->dflt && !sleaf->dflt->realtype->plugin->compare(sleaf->dflt,
&((struct lyd_node_term *)src_diff)->value)) {
/* we deleted it, so a default value was in-use, and it matches the created value -> operation NONE */
LY_CHECK_RET(lyd_diff_change_op(diff_match, LYD_DIFF_OP_NONE));
} else if (!lyd_compare_single(diff_match, src_diff, 0)) {
/* deleted + created -> operation NONE */
LY_CHECK_RET(lyd_diff_change_op(diff_match, LYD_DIFF_OP_NONE));
} else {
/* we deleted it, but it was created with a different value -> operation REPLACE */
LY_CHECK_RET(lyd_diff_change_op(diff_match, LYD_DIFF_OP_REPLACE));
/* current value is the previous one (meta) */
LY_CHECK_RET(lyd_new_meta(LYD_CTX(src_diff), diff_match, NULL, "yang:orig-value",
lyd_get_value(diff_match), 0, NULL));
/* update the value itself */
LY_CHECK_RET(lyd_change_term(diff_match, lyd_get_value(src_diff)));
}
} else {
/* deleted + created -> operation NONE */
LY_CHECK_RET(lyd_diff_change_op(diff_match, LYD_DIFF_OP_NONE));
}
if (diff_match->schema->nodetype & LYD_NODE_TERM) {
/* add orig-dflt metadata */
LY_CHECK_RET(lyd_new_meta(LYD_CTX(src_diff), diff_match, NULL, "yang:orig-default",
trg_flags & LYD_DEFAULT ? "true" : "false", 0, NULL));
/* update dflt flag itself */
diff_match->flags &= ~LYD_DEFAULT;
diff_match->flags |= src_diff->flags & LYD_DEFAULT;
}
/* but the operation of its children should remain DELETE */
LY_LIST_FOR(lyd_child_no_keys(diff_match), child) {
LY_CHECK_RET(lyd_diff_change_op(child, LYD_DIFF_OP_DELETE));
}
break;
default:
/* create and replace operations are not valid */
LOGINT_RET(LYD_CTX(src_diff));
}
return LY_SUCCESS;
}
/**
* @brief Update operations on a diff node when the new operation is DELETE.
*
* @param[in] diff_match Node from the diff.
* @param[in] cur_op Current operation of @p diff_match.
* @param[in] src_diff Current source diff node.
* @return LY_ERR value.
*/
static LY_ERR
lyd_diff_merge_delete(struct lyd_node *diff_match, enum lyd_diff_op cur_op, const struct lyd_node *src_diff)
{
struct lyd_node *next, *child;
struct lyd_meta *meta;
const char *meta_name;
/* we can delete only exact existing nodes */
LY_CHECK_ERR_RET(lyd_compare_single(diff_match, src_diff, 0), LOGINT(LYD_CTX(src_diff)), LY_EINT);
switch (cur_op) {
case LYD_DIFF_OP_CREATE:
/* it was created, but then deleted -> set NONE operation */
LY_CHECK_RET(lyd_diff_change_op(diff_match, LYD_DIFF_OP_NONE));
if (diff_match->schema->nodetype & LYD_NODE_TERM) {
/* add orig-default meta because it is expected */
LY_CHECK_RET(lyd_new_meta(LYD_CTX(src_diff), diff_match, NULL, "yang:orig-default",
diff_match->flags & LYD_DEFAULT ? "true" : "false", 0, NULL));
} else if (!lysc_is_dup_inst_list(diff_match->schema)) {
/* keep operation for all descendants (for now) */
LY_LIST_FOR(lyd_child_no_keys(diff_match), child) {
LY_CHECK_RET(lyd_diff_change_op(child, cur_op));
}
} /* else key-less list, for which all the descendants act as keys */
break;
case LYD_DIFF_OP_REPLACE:
/* similar to none operation but also remove the redundant metadata */
if (lysc_is_userordered(diff_match->schema)) {
if (lysc_is_dup_inst_list(diff_match->schema)) {
meta_name = "position";
} else if (diff_match->schema->nodetype == LYS_LIST) {
meta_name = "key";
} else {
meta_name = "value";
}
} else {
assert(diff_match->schema->nodetype == LYS_LEAF);
/* switch value for the original one */
meta = lyd_find_meta(diff_match->meta, NULL, "yang:orig-value");
LY_CHECK_ERR_RET(!meta, LOGINT(LYD_CTX(src_diff)), LY_EINT);
if (lyd_change_term(diff_match, lyd_get_meta_value(meta))) {
LOGINT_RET(LYD_CTX(src_diff));
}
/* switch default for the original one, then remove the meta */
meta = lyd_find_meta(diff_match->meta, NULL, "yang:orig-default");
LY_CHECK_ERR_RET(!meta, LOGINT(LYD_CTX(src_diff)), LY_EINT);
diff_match->flags &= ~LYD_DEFAULT;
if (meta->value.boolean) {
diff_match->flags |= LYD_DEFAULT;
}
lyd_free_meta_single(meta);
meta_name = "orig-value";
}
lyd_diff_del_meta(diff_match, meta_name);
/* fall through */
case LYD_DIFF_OP_NONE:
/* it was not modified, but should be deleted -> set DELETE operation */
LY_CHECK_RET(lyd_diff_change_op(diff_match, LYD_DIFF_OP_DELETE));
/* all descendants not in the diff will be deleted and redundant in the diff, so remove them */
LY_LIST_FOR_SAFE(lyd_child_no_keys(diff_match), next, child) {
if (lyd_find_sibling_first(lyd_child(src_diff), child, NULL) == LY_ENOTFOUND) {
lyd_free_tree(child);
}
}
break;
default:
/* delete operation is not valid */
LOGINT_RET(LYD_CTX(src_diff));
}
return LY_SUCCESS;
}
/**
* @brief Check whether this diff node is redundant (does not change data).
*
* @param[in] diff Diff node.
* @return 0 if not, non-zero if it is.
*/
static int
lyd_diff_is_redundant(struct lyd_node *diff)
{
enum lyd_diff_op op;
struct lyd_meta *meta, *orig_val_meta = NULL, *val_meta = NULL;
struct lyd_node *child;
const struct lys_module *mod;
const char *str, *orig_meta_name, *meta_name;
assert(diff);
if (lysc_is_dup_inst_list(diff->schema)) {
/* all descendants are keys */
child = NULL;
} else {
child = lyd_child_no_keys(diff);
}
mod = ly_ctx_get_module_latest(LYD_CTX(diff), "yang");
assert(mod);
/* get node operation */
LY_CHECK_RET(lyd_diff_get_op(diff, &op), 0);
if ((op == LYD_DIFF_OP_REPLACE) && lysc_is_userordered(diff->schema)) {
/* get metadata names */
if (lysc_is_dup_inst_list(diff->schema)) {
meta_name = "position";
orig_meta_name = "orig-position";
} else if (diff->schema->nodetype == LYS_LIST) {
meta_name = "key";
orig_meta_name = "orig-key";
} else {
meta_name = "value";
orig_meta_name = "orig-value";
}
/* check for redundant move */
orig_val_meta = lyd_find_meta(diff->meta, mod, orig_meta_name);
val_meta = lyd_find_meta(diff->meta, mod, meta_name);
assert(orig_val_meta && val_meta);
if (!lyd_compare_meta(orig_val_meta, val_meta)) {
/* there is actually no move */
lyd_free_meta_single(orig_val_meta);
lyd_free_meta_single(val_meta);
if (child) {
/* change operation to NONE, we have siblings */
lyd_diff_change_op(diff, LYD_DIFF_OP_NONE);
return 0;
}
/* redundant node, BUT !!
* In diff the move operation is always converted to be INSERT_AFTER, which is fine
* because the data that this is applied on should not change for the diff lifetime.
* However, when we are merging 2 diffs, this conversion is actually lossy because
* if the data change, the move operation can also change its meaning. In this specific
* case the move operation will be lost. But it can be considered a feature, it is not supported.
*/
return 1;
}
} else if ((op == LYD_DIFF_OP_NONE) && (diff->schema->nodetype & LYD_NODE_TERM)) {
/* check whether at least the default flags are different */
meta = lyd_find_meta(diff->meta, mod, "orig-default");
assert(meta);
str = lyd_get_meta_value(meta);
/* if previous and current dflt flags are the same, this node is redundant */
if ((!strcmp(str, "true") && (diff->flags & LYD_DEFAULT)) || (!strcmp(str, "false") && !(diff->flags & LYD_DEFAULT))) {
return 1;
}
return 0;
}
if (!child && (op == LYD_DIFF_OP_NONE)) {
return 1;
}
return 0;
}
/**
* @brief Merge sysrepo diff subtree with another diff, recursively.
*
* @param[in] src_diff Source diff node.
* @param[in] diff_parent Current sysrepo diff parent.
* @param[in] diff_cb Optional diff callback.
* @param[in] cb_data User data for @p diff_cb.
* @param[in,out] dup_inst Duplicate instance cache for all @p src_diff siblings.
* @param[in] options Diff merge options.
* @param[in,out] diff Diff root node.
* @return LY_ERR value.
*/
static LY_ERR
lyd_diff_merge_r(const struct lyd_node *src_diff, struct lyd_node *diff_parent, lyd_diff_cb diff_cb, void *cb_data,
struct lyd_dup_inst **dup_inst, uint16_t options, struct lyd_node **diff)
{
LY_ERR ret = LY_SUCCESS;
struct lyd_node *child, *diff_node = NULL;
enum lyd_diff_op src_op, cur_op;
struct lyd_dup_inst *child_dup_inst = NULL;
/* get source node operation */
LY_CHECK_RET(lyd_diff_get_op(src_diff, &src_op));
/* find an equal node in the current diff */
LY_CHECK_RET(lyd_diff_find_match(diff_parent ? lyd_child_no_keys(diff_parent) : *diff, src_diff, 1, dup_inst, &diff_node));
if (diff_node) {
/* get target (current) operation */
LY_CHECK_RET(lyd_diff_get_op(diff_node, &cur_op));
/* merge operations */
switch (src_op) {
case LYD_DIFF_OP_REPLACE:
ret = lyd_diff_merge_replace(diff_node, cur_op, src_diff);
break;
case LYD_DIFF_OP_CREATE:
if ((cur_op == LYD_DIFF_OP_CREATE) && lysc_is_dup_inst_list(diff_node->schema)) {
/* special case of creating duplicate (leaf-)list instances */
goto add_diff;
}
ret = lyd_diff_merge_create(diff_node, cur_op, src_diff, options);
break;
case LYD_DIFF_OP_DELETE:
ret = lyd_diff_merge_delete(diff_node, cur_op, src_diff);
break;
case LYD_DIFF_OP_NONE:
/* key-less list can never have "none" operation since all its descendants are acting as "keys" */
assert((src_diff->schema->nodetype != LYS_LIST) || !lysc_is_dup_inst_list(src_diff->schema));
ret = lyd_diff_merge_none(diff_node, cur_op, src_diff);
break;
default:
LOGINT_RET(LYD_CTX(src_diff));
}
if (ret) {
LOGERR(LYD_CTX(src_diff), LY_EOTHER, "Merging operation \"%s\" failed.", lyd_diff_op2str(src_op));
return ret;
}
if (diff_cb) {
/* call callback */
LY_CHECK_RET(diff_cb(src_diff, diff_node, cb_data));
}
/* update diff parent */
diff_parent = diff_node;
/* for diff purposes, all key-less list descendants actually act as keys (identifying the same instances),
* so there is nothing to merge for these "keys" */
if (!lysc_is_dup_inst_list(src_diff->schema)) {
/* merge src_diff recursively */
LY_LIST_FOR(lyd_child_no_keys(src_diff), child) {
ret = lyd_diff_merge_r(child, diff_parent, diff_cb, cb_data, &child_dup_inst, options, diff);
if (ret) {
break;
}
}
lyd_dup_inst_free(child_dup_inst);
LY_CHECK_RET(ret);
}
} else {
add_diff:
/* add new diff node with all descendants */
LY_CHECK_RET(lyd_dup_single(src_diff, (struct lyd_node_inner *)diff_parent, LYD_DUP_RECURSIVE | LYD_DUP_WITH_FLAGS,
&diff_node));
/* insert node into diff if not already */
if (!diff_parent) {
lyd_insert_sibling(*diff, diff_node, diff);
}
/* update operation */
LY_CHECK_RET(lyd_diff_change_op(diff_node, src_op));
if (diff_cb) {
/* call callback with no source diff node since it was duplicated and just added */
LY_CHECK_RET(diff_cb(NULL, diff_node, cb_data));
}
/* update diff parent */
diff_parent = diff_node;
}
/* remove any redundant nodes */
if (lyd_diff_is_redundant(diff_parent)) {
if (diff_parent == *diff) {
*diff = (*diff)->next;
}
lyd_free_tree(diff_parent);
}
return LY_SUCCESS;
}
API LY_ERR
lyd_diff_merge_module(struct lyd_node **diff, const struct lyd_node *src_diff, const struct lys_module *mod,
lyd_diff_cb diff_cb, void *cb_data, uint16_t options)
{
const struct lyd_node *src_root;
struct lyd_dup_inst *dup_inst = NULL;
LY_ERR ret = LY_SUCCESS;
LY_LIST_FOR(src_diff, src_root) {
if (mod && (lyd_owner_module(src_root) != mod)) {
/* skip data nodes from different modules */
continue;
}
/* apply relevant nodes from the diff datatree */
LY_CHECK_GOTO(ret = lyd_diff_merge_r(src_root, NULL, diff_cb, cb_data, &dup_inst, options, diff), cleanup);
}
cleanup:
lyd_dup_inst_free(dup_inst);
return ret;
}
API LY_ERR
lyd_diff_merge_tree(struct lyd_node **diff_first, struct lyd_node *diff_parent, const struct lyd_node *src_sibling,
lyd_diff_cb diff_cb, void *cb_data, uint16_t options)
{
LY_ERR ret;
struct lyd_dup_inst *dup_inst = NULL;
if (!src_sibling) {
return LY_SUCCESS;
}
ret = lyd_diff_merge_r(src_sibling, diff_parent, diff_cb, cb_data, &dup_inst, options, diff_first);
lyd_dup_inst_free(dup_inst);
return ret;
}
API LY_ERR
lyd_diff_merge_all(struct lyd_node **diff, const struct lyd_node *src_diff, uint16_t options)
{
return lyd_diff_merge_module(diff, src_diff, NULL, NULL, NULL, options);
}
static LY_ERR
lyd_diff_reverse_value(struct lyd_node *node, const struct lys_module *mod)
{
LY_ERR ret = LY_SUCCESS;
struct lyd_meta *meta;
const char *val1 = NULL;
char *val2;
uint32_t flags;
assert(node->schema->nodetype & (LYS_LEAF | LYS_ANYDATA));
meta = lyd_find_meta(node->meta, mod, "orig-value");
LY_CHECK_ERR_RET(!meta, LOGINT(LYD_CTX(node)), LY_EINT);
/* orig-value */
val1 = lyd_get_meta_value(meta);
/* current value */
if (node->schema->nodetype == LYS_LEAF) {
val2 = strdup(lyd_get_value(node));
} else {
LY_CHECK_RET(lyd_any_value_str(node, &val2));
}
/* switch values, keep default flag */
flags = node->flags;
if (node->schema->nodetype == LYS_LEAF) {
LY_CHECK_GOTO(ret = lyd_change_term(node, val1), cleanup);
} else {
union lyd_any_value anyval = {.str = val1};
LY_CHECK_GOTO(ret = lyd_any_copy_value(node, &anyval, LYD_ANYDATA_STRING), cleanup);
}
node->flags = flags;
LY_CHECK_GOTO(ret = lyd_change_meta(meta, val2), cleanup);
cleanup:
free(val2);
return ret;
}
static LY_ERR
lyd_diff_reverse_default(struct lyd_node *node, const struct lys_module *mod)
{
struct lyd_meta *meta;
uint32_t flag1, flag2;
meta = lyd_find_meta(node->meta, mod, "orig-default");
LY_CHECK_ERR_RET(!meta, LOGINT(mod->ctx), LY_EINT);
/* orig-default */
if (meta->value.boolean) {
flag1 = LYD_DEFAULT;
} else {
flag1 = 0;
}
/* current default */
flag2 = node->flags & LYD_DEFAULT;
if (flag1 == flag2) {
/* no default state change so nothing to reverse */
return LY_SUCCESS;
}
/* switch defaults */
node->flags &= ~LYD_DEFAULT;
node->flags |= flag1;
LY_CHECK_RET(lyd_change_meta(meta, flag2 ? "true" : "false"));
return LY_SUCCESS;
}
static LY_ERR
lyd_diff_reverse_meta(struct lyd_node *node, const struct lys_module *mod, const char *name1, const char *name2)
{
LY_ERR ret = LY_SUCCESS;
struct lyd_meta *meta1, *meta2;
const char *val1 = NULL;
char *val2 = NULL;
meta1 = lyd_find_meta(node->meta, mod, name1);
LY_CHECK_ERR_RET(!meta1, LOGINT(LYD_CTX(node)), LY_EINT);
meta2 = lyd_find_meta(node->meta, mod, name2);
LY_CHECK_ERR_RET(!meta2, LOGINT(LYD_CTX(node)), LY_EINT);
/* value1 */
val1 = lyd_get_meta_value(meta1);
/* value2 */
val2 = strdup(lyd_get_meta_value(meta2));
/* switch values */
LY_CHECK_GOTO(ret = lyd_change_meta(meta1, val2), cleanup);
LY_CHECK_GOTO(ret = lyd_change_meta(meta2, val1), cleanup);
cleanup:
free(val2);
return ret;
}
/**
* @brief Remove specific operation from all the nodes in a subtree.
*
* @param[in] diff Diff subtree to process.
* @param[in] op Only expected operation.
* @return LY_ERR value.
*/
static LY_ERR
lyd_diff_reverse_remove_op_r(struct lyd_node *diff, enum lyd_diff_op op)
{
struct lyd_node *elem;
struct lyd_meta *meta;
LYD_TREE_DFS_BEGIN(diff, elem) {
meta = lyd_find_meta(elem->meta, NULL, "yang:operation");
if (meta) {
LY_CHECK_ERR_RET(lyd_diff_str2op(lyd_get_meta_value(meta)) != op, LOGINT(LYD_CTX(diff)), LY_EINT);
lyd_free_meta_single(meta);
}
LYD_TREE_DFS_END(diff, elem);
}
return LY_SUCCESS;
}
API LY_ERR
lyd_diff_reverse_all(const struct lyd_node *src_diff, struct lyd_node **diff)
{
LY_ERR ret = LY_SUCCESS;
const struct lys_module *mod;
struct lyd_node *root, *elem, *iter;
enum lyd_diff_op op;
LY_CHECK_ARG_RET(NULL, diff, LY_EINVAL);
if (!src_diff) {
*diff = NULL;
return LY_SUCCESS;
}
/* duplicate diff */
LY_CHECK_RET(lyd_dup_siblings(src_diff, NULL, LYD_DUP_RECURSIVE, diff));
/* find module with metadata needed for later */
mod = ly_ctx_get_module_latest(LYD_CTX(src_diff), "yang");
LY_CHECK_ERR_GOTO(!mod, LOGINT(LYD_CTX(src_diff)); ret = LY_EINT, cleanup);
LY_LIST_FOR(*diff, root) {
LYD_TREE_DFS_BEGIN(root, elem) {
/* skip all keys */
if (!lysc_is_key(elem->schema)) {
/* find operation attribute, if any */
LY_CHECK_GOTO(ret = lyd_diff_get_op(elem, &op), cleanup);
switch (op) {
case LYD_DIFF_OP_CREATE:
/* reverse create to delete */
LY_CHECK_GOTO(ret = lyd_diff_change_op(elem, LYD_DIFF_OP_DELETE), cleanup);
/* check all the children for the same operation, nothing else is expected */
LY_LIST_FOR(lyd_child(elem), iter) {
lyd_diff_reverse_remove_op_r(iter, LYD_DIFF_OP_CREATE);
}
LYD_TREE_DFS_continue = 1;
break;
case LYD_DIFF_OP_DELETE:
/* reverse delete to create */
LY_CHECK_GOTO(ret = lyd_diff_change_op(elem, LYD_DIFF_OP_CREATE), cleanup);
/* check all the children for the same operation, nothing else is expected */
LY_LIST_FOR(lyd_child(elem), iter) {
lyd_diff_reverse_remove_op_r(iter, LYD_DIFF_OP_DELETE);
}
LYD_TREE_DFS_continue = 1;
break;
case LYD_DIFF_OP_REPLACE:
switch (elem->schema->nodetype) {
case LYS_LEAF:
/* leaf value change */
LY_CHECK_GOTO(ret = lyd_diff_reverse_value(elem, mod), cleanup);
LY_CHECK_GOTO(ret = lyd_diff_reverse_default(elem, mod), cleanup);
break;
case LYS_ANYXML:
case LYS_ANYDATA:
/* any value change */
LY_CHECK_GOTO(ret = lyd_diff_reverse_value(elem, mod), cleanup);
break;
case LYS_LEAFLIST:
/* leaf-list move */
LY_CHECK_GOTO(ret = lyd_diff_reverse_default(elem, mod), cleanup);
if (lysc_is_dup_inst_list(elem->schema)) {
LY_CHECK_GOTO(ret = lyd_diff_reverse_meta(elem, mod, "orig-position", "position"), cleanup);
} else {
LY_CHECK_GOTO(ret = lyd_diff_reverse_meta(elem, mod, "orig-value", "value"), cleanup);
}
break;
case LYS_LIST:
/* list move */
if (lysc_is_dup_inst_list(elem->schema)) {
LY_CHECK_GOTO(ret = lyd_diff_reverse_meta(elem, mod, "orig-position", "position"), cleanup);
} else {
LY_CHECK_GOTO(ret = lyd_diff_reverse_meta(elem, mod, "orig-key", "key"), cleanup);
}
break;
default:
LOGINT(LYD_CTX(src_diff));
ret = LY_EINT;
goto cleanup;
}
break;
case LYD_DIFF_OP_NONE:
switch (elem->schema->nodetype) {
case LYS_LEAF:
case LYS_LEAFLIST:
/* default flag change */
LY_CHECK_GOTO(ret = lyd_diff_reverse_default(elem, mod), cleanup);
break;
default:
/* nothing to do */
break;
}
break;
}
}
LYD_TREE_DFS_END(root, elem);
}
}
cleanup:
if (ret) {
lyd_free_siblings(*diff);
*diff = NULL;
}
return ret;
}