diff options
Diffstat (limited to 'src/diff.c')
| -rw-r--r-- | src/diff.c | 2151 |
1 files changed, 2151 insertions, 0 deletions
diff --git a/src/diff.c b/src/diff.c new file mode 100644 index 0000000..edfcb34 --- /dev/null +++ b/src/diff.c @@ -0,0 +1,2151 @@ +/** + * @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_exts.h" +#include "plugins_exts/metadata.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" + +#define LOGERR_META(ctx, meta_name, node) \ + { \ + char *__path = lyd_path(node, LYD_PATH_STD, NULL, 0); \ + LOGERR(ctx, LY_EINVAL, "Failed to find metadata \"%s\" for node \"%s\".", meta_name, __path); \ + free(__path); \ + } + +#define LOGERR_NOINST(ctx, node) \ + { \ + char *__path = lyd_path(node, LYD_PATH_STD, NULL, 0); \ + LOGERR(ctx, LY_EINVAL, "Failed to find node \"%s\" instance in data.", __path); \ + free(__path); \ + } + +#define LOGERR_UNEXPVAL(ctx, node, data_source) \ + { \ + char *__path = lyd_path(node, LYD_PATH_STD, NULL, 0); \ + LOGERR(ctx, LY_EINVAL, "Unexpected value of node \"%s\" in %s.", __path, data_source); \ + free(__path); \ + } + +#define LOGERR_MERGEOP(ctx, node, src_op, trg_op) \ + { \ + char *__path = lyd_path(node, LYD_PATH_STD, NULL, 0); \ + LOGERR(ctx, LY_EINVAL, "Unable to merge operation \"%s\" with \"%s\" for node \"%s\".", \ + lyd_diff_op2str(trg_op), lyd_diff_op2str(src_op), __path); \ + free(__path); \ + } + +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; +} + +/** + * @brief Create diff metadata for a nested user-ordered node with the effective operation "create". + * + * @param[in] node User-rodered node to update. + * @return LY_ERR value. + */ +static LY_ERR +lyd_diff_add_create_nested_userord(struct lyd_node *node) +{ + LY_ERR rc = LY_SUCCESS; + const char *meta_name, *meta_val; + size_t buflen = 0, bufused = 0; + uint32_t pos; + char *dyn = NULL; + + assert(lysc_is_userordered(node->schema)); + + /* get correct metadata name and value */ + if (lysc_is_dup_inst_list(node->schema)) { + meta_name = "yang:position"; + + pos = lyd_list_pos(node); + if (asprintf(&dyn, "%" PRIu32, pos) == -1) { + LOGMEM(LYD_CTX(node)); + rc = LY_EMEM; + goto cleanup; + } + meta_val = dyn; + } else if (node->schema->nodetype == LYS_LIST) { + meta_name = "yang:key"; + + if (node->prev->next && (node->prev->schema == node->schema)) { + LY_CHECK_GOTO(rc = lyd_path_list_predicate(node->prev, &dyn, &buflen, &bufused, 0), cleanup); + meta_val = dyn; + } else { + meta_val = ""; + } + } else { + meta_name = "yang:value"; + + if (node->prev->next && (node->prev->schema == node->schema)) { + meta_val = lyd_get_value(node->prev); + } else { + meta_val = ""; + } + } + + /* create the metadata */ + LY_CHECK_GOTO(rc = lyd_new_meta(NULL, node, NULL, meta_name, meta_val, 0, NULL), cleanup); + +cleanup: + free(dyn); + return rc; +} + +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, *elem; + const struct lyd_node *parent = NULL; + + 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); + } + + /* add parent operation, if any */ + if (diff_parent && (diff_parent != dup)) { + LY_CHECK_RET(lyd_new_meta(NULL, diff_parent, NULL, "yang:operation", "none", 0, NULL)); + } + + /* add subtree operation */ + LY_CHECK_RET(lyd_new_meta(NULL, dup, NULL, "yang:operation", lyd_diff_op2str(op), 0, NULL)); + + if (op == LYD_DIFF_OP_CREATE) { + /* all nested user-ordered (leaf-)lists need special metadata for create op */ + LYD_TREE_DFS_BEGIN(dup, elem) { + if ((elem != dup) && lysc_is_userordered(elem->schema)) { + LY_CHECK_RET(lyd_diff_add_create_nested_userord(elem)); + } + LYD_TREE_DFS_END(dup, elem); + } + } + + /* orig-default */ + if (orig_default) { + LY_CHECK_RET(lyd_new_meta(NULL, dup, NULL, "yang:orig-default", orig_default, 0, NULL)); + } + + /* orig-value */ + if (orig_value) { + LY_CHECK_RET(lyd_new_meta(NULL, dup, NULL, "yang:orig-value", orig_value, 0, NULL)); + } + + /* key */ + if (key) { + LY_CHECK_RET(lyd_new_meta(NULL, dup, NULL, "yang:key", key, 0, NULL)); + } + + /* value */ + if (value) { + LY_CHECK_RET(lyd_new_meta(NULL, dup, NULL, "yang:value", value, 0, NULL)); + } + + /* position */ + if (position) { + LY_CHECK_RET(lyd_new_meta(NULL, dup, NULL, "yang:position", position, 0, NULL)); + } + + /* orig-key */ + if (orig_key) { + LY_CHECK_RET(lyd_new_meta(NULL, dup, NULL, "yang:orig-key", orig_key, 0, NULL)); + } + + /* orig-position */ + if (orig_position) { + LY_CHECK_RET(lyd_new_meta(NULL, dup, NULL, "yang: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] userord_item Userord item of @p first and/or @p second node. + * @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_item, enum lyd_diff_op *op, const char **orig_default, char **value, + char **orig_value, char **key, char **orig_key, char **position, char **orig_position) +{ + LY_ERR rc = LY_SUCCESS; + const struct lysc_node *schema; + size_t buflen, bufused; + uint32_t first_pos, second_pos; + + 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)); + + /* 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_GOTO(!*value, LOGMEM(schema->module->ctx); rc = LY_EMEM, cleanup); + } else { + *value = strdup(""); + LY_CHECK_ERR_GOTO(!*value, LOGMEM(schema->module->ctx); rc = LY_EMEM, cleanup); + } + } + + /* 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_GOTO(!*orig_value, LOGMEM(schema->module->ctx); rc = LY_EMEM, cleanup); + } else { + *orig_value = strdup(""); + LY_CHECK_ERR_GOTO(!*orig_value, LOGMEM(schema->module->ctx); rc = LY_EMEM, cleanup); + } + } + + /* 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_GOTO(rc = lyd_path_list_predicate(userord_item->inst[second_pos - 1], key, &buflen, &bufused, 0), cleanup); + } else { + *key = strdup(""); + LY_CHECK_ERR_GOTO(!*key, LOGMEM(schema->module->ctx); rc = LY_EMEM, cleanup); + } + } + + /* 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_GOTO(rc = lyd_path_list_predicate(userord_item->inst[first_pos - 1], orig_key, &buflen, &bufused, 0), cleanup); + } else { + *orig_key = strdup(""); + LY_CHECK_ERR_GOTO(!*orig_key, LOGMEM(schema->module->ctx); rc = LY_EMEM, cleanup); + } + } + + /* 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); + rc = LY_EMEM; + goto cleanup; + } + } else { + *position = strdup(""); + LY_CHECK_ERR_GOTO(!*position, LOGMEM(schema->module->ctx); rc = LY_EMEM, cleanup); + } + } + + /* 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); + rc = LY_EMEM; + goto cleanup; + } + } else { + *orig_position = strdup(""); + LY_CHECK_ERR_GOTO(!*orig_position, LOGMEM(schema->module->ctx); rc = LY_EMEM, cleanup); + } + } + + /* + * update our instances - apply the change + */ + if (*op == LYD_DIFF_OP_CREATE) { + /* insert the instance */ + LY_ARRAY_CREATE_GOTO(schema->module->ctx, userord_item->inst, 1, rc, cleanup); + 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; + } + +cleanup: + if (rc) { + free(*value); + *value = NULL; + free(*orig_value); + *orig_value = NULL; + free(*key); + *key = NULL; + free(*orig_key); + *orig_key = NULL; + free(*position); + *position = NULL; + free(*orig_position); + *orig_position = NULL; + } + return rc; +} + +/** + * @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; + const char *str_val; + + 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) { + str_val = lyd_get_value(first); + *orig_value = strdup(str_val ? str_val : ""); + 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) +{ + LY_ERR r; + + if (target->schema->nodetype & (LYS_LIST | LYS_LEAFLIST)) { + /* try to find the exact instance */ + r = lyd_find_sibling_first(siblings, target, match); + } else { + /* try to simply find the node, there cannot be more instances */ + r = lyd_find_sibling_val(siblings, target->schema, NULL, 0, match); + } + if (r && (r != LY_ENOTFOUND)) { + return r; + } + + /* 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, *userord_item; + 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) { + if (!iter_first->schema) { + continue; + } + + 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)) { + /* get (create) userord entry */ + userord_item = lyd_diff_userord_get(iter_first, iter_first->schema, &userord); + LY_CHECK_ERR_GOTO(!userord_item, LOGMEM(LYD_CTX(iter_first)); ret = LY_EMEM, cleanup); + + /* 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_item, &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) { + if (!iter_second->schema) { + continue; + } + + 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 userord entry */ + userord_item = lyd_diff_userord_get(match_first, iter_second->schema, &userord); + LY_CHECK_ERR_GOTO(!userord_item, LOGMEM(LYD_CTX(iter_second)); ret = LY_EMEM, cleanup); + + /* get all the attributes */ + ret = lyd_diff_userord_attrs(match_first, iter_second, options, userord_item, &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); +} + +LIBYANG_API_DEF 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); +} + +LIBYANG_API_DEF 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; + char *path; + + 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; + } + } + + if (!meta) { + path = lyd_path(diff_node, LYD_PATH_STD, NULL, 0); + LOGERR(LYD_CTX(diff_node), LY_EINVAL, "Node \"%s\" without an operation.", path); + free(path); + return 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); + if (!anchor_pos) { + LOGERR(LYD_CTX(new_node), LY_EINVAL, "Invalid user-ordered anchor value \"%s\".", userord_anchor); + return LY_EINVAL; + } + + 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 { + /* find the first instance */ + ret = lyd_find_sibling_val(*first_node, new_node->schema, NULL, 0, &anchor); + LY_CHECK_RET(ret && (ret != LY_ENOTFOUND), ret); + + if (anchor) { + /* insert before the first instance */ + LY_CHECK_RET(lyd_insert_before(anchor, new_node)); + if ((*first_node)->prev->next) { + assert(!new_node->prev->next); + *first_node = new_node; + } + } else { + /* insert anywhere */ + LY_CHECK_RET(lyd_insert_sibling(*first_node, new_node, first_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, LOGERR_NOINST(ctx, diff_node), LY_EINVAL); + } 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, LOGERR_META(ctx, meta_str, diff_node), LY_EINVAL); + 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, LOGERR_NOINST(ctx, diff_node), LY_EINVAL); + + 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)) { + LOGERR(ctx, LY_EINVAL, "Operation \"none\" is invalid for node \"%s\" without children.", + LYD_NAME(diff_node)); + return LY_EINVAL; + } + } + 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) { + if (match->flags & LYD_EXT) { + ret = lyplg_ext_insert(parent_node, match); + } else { + 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, LOGERR_NOINST(ctx, diff_node), LY_EINVAL); + + /* 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: + if (!(diff_node->schema->nodetype & (LYS_LEAF | LYS_ANYDATA))) { + LOGERR(ctx, LY_EINVAL, "Operation \"replace\" is invalid for %s node \"%s\".", + lys_nodetype2str(diff_node->schema->nodetype), LYD_NAME(diff_node)); + return LY_EINVAL; + } + + /* find the node */ + LY_CHECK_RET(lyd_diff_find_match(*first_node, diff_node, 1, dup_inst, &match)); + LY_CHECK_ERR_RET(!match, LOGERR_NOINST(ctx, diff_node), LY_EINVAL); + + /* update the value */ + if (diff_node->schema->nodetype == LYS_LEAF) { + ret = lyd_change_term(match, lyd_get_value(diff_node)); + LY_CHECK_ERR_RET(ret && (ret != LY_EEXIST), LOGERR_UNEXPVAL(ctx, match, "data"), LY_EINVAL); + } 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; +} + +LIBYANG_API_DEF 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; +} + +LIBYANG_API_DEF 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 */ + LOGERR_MERGEOP(LYD_CTX(diff_match), diff_match, cur_op, LYD_DIFF_OP_NONE); + return LY_EINVAL; + } + + 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; + const struct ly_ctx *ctx = LYD_CTX(diff_match); + + /* 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, LOGERR_META(ctx, meta_name, src_diff), LY_EINVAL); + 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)) { + LOGERR_UNEXPVAL(ctx, diff_match, "target diff"); + return LY_EINVAL; + } + + /* 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, LOGERR_META(ctx, "orig-value", diff_match), LY_EINVAL); + 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)) { + LOGERR_UNEXPVAL(ctx, diff_match, "target diff"); + return LY_EINVAL; + } + + /* 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, LOGERR_META(ctx, orig_meta_name, src_diff), LY_EINVAL); + 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, LOGERR_META(ctx, meta_name, src_diff), LY_EINVAL); + LY_CHECK_RET(lyd_dup_meta_single(meta, diff_match, NULL)); + break; + default: + /* delete operation is not valid */ + LOGERR_MERGEOP(ctx, diff_match, cur_op, LYD_DIFF_OP_REPLACE); + return LY_EINVAL; + } + + 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; + const struct ly_ctx *ctx = LYD_CTX(diff_match); + + 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); + LY_CHECK_ERR_RET(!meta, LOGERR_META(ctx, meta_name, src_diff), LY_EINVAL); + orig_meta = lyd_find_meta(diff_match->meta, NULL, orig_meta_name); + LY_CHECK_ERR_RET(!orig_meta, LOGERR_META(ctx, orig_meta_name, diff_match), LY_EINVAL); + + /* 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 */ + LOGERR_MERGEOP(LYD_CTX(src_diff), diff_match, cur_op, LYD_DIFF_OP_CREATE); + return LY_EINVAL; + } + + 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 *child; + struct lyd_meta *meta; + const char *meta_name; + const struct ly_ctx *ctx = LYD_CTX(diff_match); + + /* 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: + /* 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, LOGERR_META(ctx, "yang:orig-value", diff_match), LY_EINVAL); + if (lyd_change_term(diff_match, lyd_get_meta_value(meta))) { + LOGERR_UNEXPVAL(ctx, diff_match, "target diff"); + return LY_EINVAL; + } + + /* 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, LOGERR_META(ctx, "yang:orig-default", diff_match), LY_EINVAL); + 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); + + /* it was being changed, but should be deleted instead -> set DELETE operation */ + LY_CHECK_RET(lyd_diff_change_op(diff_match, LYD_DIFF_OP_DELETE)); + break; + 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)); + break; + default: + /* delete operation is not valid */ + LOGERR_MERGEOP(LYD_CTX(diff_match), diff_match, cur_op, LYD_DIFF_OP_DELETE); + return LY_EINVAL; + } + + 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 */ + if ((src_diff->flags & LYD_EXT) && diff_parent) { + LY_CHECK_RET(lyd_dup_single_to_ctx(src_diff, LYD_CTX(diff_parent), (struct lyd_node_inner *)diff_parent, + LYD_DUP_RECURSIVE | LYD_DUP_WITH_FLAGS, &diff_node)); + } else { + 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; +} + +LIBYANG_API_DEF 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; +} + +LIBYANG_API_DEF 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; +} + +LIBYANG_API_DEF 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, LOGERR_META(LYD_CTX(node), "orig-value", node), LY_EINVAL); + + /* 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, LOGERR_META(LYD_CTX(node), name1, node), LY_EINVAL); + + meta2 = lyd_find_meta(node->meta, mod, name2); + LY_CHECK_ERR_RET(!meta2, LOGERR_META(LYD_CTX(node), name2, node), LY_EINVAL); + + /* 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; +} + +LIBYANG_API_DEF 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; +} |