blob: 48ddf736d7b4da164b1226e20bb71778d089afa4 [file] [log] [blame]
/**
* @file parser_xml.c
* @author Radek Krejci <rkrejci@cesnet.cz>
* @brief XML data parser for libyang
*
* Copyright (c) 2019 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
*/
#include "common.h"
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include "context.h"
#include "dict.h"
#include "log.h"
#include "plugins_types.h"
#include "set.h"
#include "tree_data.h"
#include "tree_data_internal.h"
#include "tree_schema.h"
#include "xml.h"
/**
* @brief internal context for XML YANG data parser.
*
* The leading part is compatible with the struct lyxml_context
*/
struct lyd_xml_ctx {
struct ly_ctx *ctx; /**< libyang context */
uint64_t line; /**< number of the line being currently processed */
enum LYXML_PARSER_STATUS status; /**< status providing information about the next expected object in input data */
struct ly_set elements; /**< list of not-yet-closed elements */
struct ly_set ns; /**< handled with LY_SET_OPT_USEASLIST */
uint16_t options; /**< various @ref dataparseroptions. */
uint16_t path_len; /**< used bytes in the path buffer */
#define LYD_PARSER_BUFSIZE 4078
char path[LYD_PARSER_BUFSIZE]; /**< buffer for the generated path */
struct ly_set incomplete_type_validation; /**< set of nodes validated with LY_EINCOMPLETE result */
};
/**
* @brief XML-parser's implementation of ly_type_resolve_prefix() callback to provide mapping between prefixes used in the values to the schema
* via XML namespaces.
*/
static const struct lys_module *
lydxml_resolve_prefix(struct ly_ctx *ctx, const char *prefix, size_t prefix_len, void *parser)
{
const struct lyxml_ns *ns;
struct lyxml_context *xmlctx = (struct lyxml_context*)parser;
ns = lyxml_ns_get(xmlctx, prefix, prefix_len);
if (!ns) {
return NULL;
}
return ly_ctx_get_module_implemented_ns(ctx, ns->uri);
}
/**
* @brief Parse XML attributes of the XML element of YANG data.
*
* @param[in] ctx XML YANG data parser context.
* @param[in,out] data Pointer to the XML string representation of the YANG data to parse.
* @param[out] attributes Resulting list of the parsed attributes. XML namespace definitions are not parsed
* as attributes, they are stored internally in the parser context.
* @reutn LY_ERR value.
*/
static LY_ERR
lydxml_attributes(struct lyd_xml_ctx *ctx, const char **data, struct lyd_attr **attributes)
{
LY_ERR ret = LY_SUCCESS;
unsigned int u;
const char *prefix, *name;
size_t prefix_len, name_len;
struct lyd_attr *attr = NULL, *last = NULL;
const struct lyxml_ns *ns;
struct ly_set attr_prefixes = {0};
struct attr_prefix_s {
const char *prefix;
size_t prefix_len;
} *attr_prefix;
struct lys_module *mod;
while(ctx->status == LYXML_ATTRIBUTE &&
lyxml_get_attribute((struct lyxml_context*)ctx, data, &prefix, &prefix_len, &name, &name_len) == LY_SUCCESS) {
int dynamic = 0;
char *buffer = NULL, *value;
size_t buffer_size = 0, value_len;
if (!name) {
/* seems like all the attrributes were internally processed as namespace definitions */
continue;
}
/* get attribute value */
ret = lyxml_get_string((struct lyxml_context *)ctx, data, &buffer, &buffer_size, &value, &value_len, &dynamic);
LY_CHECK_GOTO(ret, cleanup);
attr = calloc(1, sizeof *attr);
LY_CHECK_ERR_GOTO(!attr, LOGMEM(ctx->ctx); ret = LY_EMEM, cleanup);
attr->name = lydict_insert(ctx->ctx, name, name_len);
/* auxiliary store the prefix information and wait with resolving prefix to the time when all the namespaces,
* defined in this element, are parsed, so we will get the correct namespace for this prefix */
attr_prefix = malloc(sizeof *attr_prefix);
attr_prefix->prefix = prefix;
attr_prefix->prefix_len = prefix_len;
ly_set_add(&attr_prefixes, attr_prefix, LY_SET_OPT_USEASLIST);
/* TODO process value */
if (last) {
last->next = attr;
} else {
(*attributes) = attr;
}
last = attr;
}
/* resolve annotation pointers in all the attributes */
for (last = *attributes, u = 0; u < attr_prefixes.count && last; u++, last = last->next) {
attr_prefix = (struct attr_prefix_s*)attr_prefixes.objs[u];
ns = lyxml_ns_get((struct lyxml_context *)ctx, attr_prefix->prefix, attr_prefix->prefix_len);
mod = ly_ctx_get_module_implemented_ns(ctx->ctx, ns->uri);
/* TODO get annotation */
}
cleanup:
ly_set_erase(&attr_prefixes, free);
return ret;
}
/**
* @brief Parse XML elements as children YANG data node of the specified parent node.
*
* @param[in] ctx XML YANG data parser context.
* @param[in] parent Parent node where the children are inserted. NULL in case of parsing top-level elements.
* @param[in,out] data Pointer to the XML string representation of the YANG data to parse.
* @param[out] node Resulting list of the parsed nodes.
* @reutn LY_ERR value.
*/
static LY_ERR
lydxml_nodes(struct lyd_xml_ctx *ctx, struct lyd_node_inner *parent, const char **data, struct lyd_node **node)
{
LY_ERR ret = LY_SUCCESS;
const char *prefix, *name;
size_t prefix_len, name_len;
struct lyd_attr *attributes = NULL;
const struct lyxml_ns *ns;
const struct lysc_node *snode;
struct lys_module *mod;
unsigned int parents_count = ctx->elements.count;
struct lyd_node *cur = NULL, *prev = NULL;
(*node) = NULL;
while(ctx->status == LYXML_ELEMENT) {
ret = lyxml_get_element((struct lyxml_context *)ctx, data, &prefix, &prefix_len, &name, &name_len);
LY_CHECK_GOTO(ret, cleanup);
if (!name) {
/* closing previous element */
if (ctx->elements.count < parents_count) {
/* all siblings parsed */
break;
} else {
continue;
}
}
attributes = NULL;
if (ctx->status == LYXML_ATTRIBUTE) {
LY_CHECK_GOTO(lydxml_attributes(ctx, data, &attributes), cleanup);
}
ns = lyxml_ns_get((struct lyxml_context *)ctx, prefix, prefix_len);
if (!ns) {
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_REFERENCE, "Unknown XML prefix \"%*.s\".", prefix_len, prefix);
goto cleanup;
}
mod = ly_ctx_get_module_implemented_ns(ctx->ctx, ns->uri);
if (!mod) {
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_REFERENCE, "No module with namespace \"%s\" in the context.", ns->uri);
goto cleanup;
}
snode = lys_child(parent ? parent->schema : NULL, mod, name, name_len, 0, (ctx->options & LYD_OPT_RPCREPLY) ? LYS_GETNEXT_OUTPUT : 0);
if (!snode) {
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_REFERENCE, "Element \"%.*s\" not found in the \"%s\" module.", name_len, name, mod->name);
goto cleanup;
}
/* allocate new node */
switch (snode->nodetype) {
case LYS_CONTAINER:
case LYS_LIST:
cur = calloc(1, sizeof(struct lyd_node_inner));
break;
case LYS_LEAF:
case LYS_LEAFLIST:
cur = calloc(1, sizeof(struct lyd_node_term));
break;
case LYS_ANYDATA:
case LYS_ANYXML:
cur = calloc(1, sizeof(struct lyd_node_any));
break;
/* TODO LYS_ACTION, LYS_NOTIF */
default:
LOGINT(ctx->ctx);
goto cleanup;
}
if (!(*node)) {
(*node) = cur;
}
cur->schema = snode;
cur->parent = parent;
if (parent) {
parent->child->prev = cur;
} else if (prev) {
struct lyd_node *iter;
for (iter = prev; iter->prev->next; iter = iter->prev);
iter->prev = cur;
}
if (prev) {
cur->prev = prev;
prev->next = cur;
} else {
cur->prev = cur;
}
prev = cur;
cur->attr = attributes;
attributes = NULL;
if (snode->nodetype & LYD_NODE_TERM) {
int dynamic = 0;
char *buffer = NULL, *value;
size_t buffer_size = 0, value_len;
if (ctx->status == LYXML_ELEM_CONTENT) {
/* get the value */
LY_ERR r = lyxml_get_string((struct lyxml_context *)ctx, data, &buffer, &buffer_size, &value, &value_len, &dynamic);
if (r == LY_EINVAL) {
/* just indentation of a child element found */
LOGVAL(ctx->ctx, LY_VLOG_LINE, &ctx->line, LYVE_SYNTAX, "Child element inside terminal node \"%s\" found.", cur->schema->name);
goto cleanup;
}
} else {
/* no content - validate empty value */
value = "";
value_len = 0;
}
ret = lyd_value_parse((struct lyd_node_term*)cur, value, value_len, dynamic, 0, lydxml_resolve_prefix, ctx, LYD_XML, NULL);
if (ret == LY_EINCOMPLETE) {
ly_set_add(&ctx->incomplete_type_validation, cur, LY_SET_OPT_USEASLIST);
} else if (ret) {
if (dynamic){
free(value);
}
goto cleanup;
}
} else if (snode->nodetype & LYD_NODE_INNER) {
int dynamic = 0;
char *buffer = NULL, *value;
size_t buffer_size = 0, value_len;
if (ctx->status == LYXML_ELEM_CONTENT) {
LY_ERR r = lyxml_get_string((struct lyxml_context *)ctx, data, &buffer, &buffer_size, &value, &value_len, &dynamic);
if (r != LY_EINVAL && (r != LY_SUCCESS || value_len != 0)) {
LOGINT(ctx->ctx);
goto cleanup;
}
}
/* process children */
if (ctx->status == LYXML_ELEMENT && parents_count != ctx->elements.count) {
ret = lydxml_nodes(ctx, (struct lyd_node_inner*)cur, data, lyd_node_children_p(cur));
LY_CHECK_GOTO(ret, cleanup);
}
} else if (snode->nodetype & LYD_NODE_ANY) {
unsigned int cur_element_index = ctx->elements.count;
const char *start = *data, *stop;
const char *p, *n;
size_t p_len, n_len;
/* skip children data and store them as a string */
while (cur_element_index <= ctx->elements.count) {
switch (ctx->status) {
case LYXML_ELEMENT:
ret = lyxml_get_element((struct lyxml_context *)ctx, data, &p, &p_len, &n, &n_len);
break;
case LYXML_ATTRIBUTE:
lyxml_get_attribute((struct lyxml_context*)ctx, data, &p, &p_len, &n, &n_len);
break;
case LYXML_ELEM_CONTENT:
case LYXML_ATTR_CONTENT:
ret = lyxml_get_string((struct lyxml_context *)ctx, data, NULL, NULL, NULL, NULL, NULL);
if (ret == LY_EINVAL) {
/* not an error, just incorrect XML parser status */
ret = LY_SUCCESS;
}
break;
case LYXML_END:
/* unexpected end of data */
LOGINT(ctx->ctx);
goto cleanup;
}
LY_CHECK_GOTO(ret, cleanup);
}
/* data now points after the anydata's closing element tag, we need just end of its content */
for (stop = *data - 1; *stop != '<'; --stop);
((struct lyd_node_any*)cur)->value_type = LYD_ANYDATA_XML;
((struct lyd_node_any*)cur)->value.xml = lydict_insert(ctx->ctx, start, stop - start);
}
/* calculate the hash and insert it into parent (list with keys is handled when its keys are inserted) */
lyd_hash(cur);
lyd_insert_hash(cur);
/* if we have empty non-presence container, we keep it, but mark it as default */
if (cur->schema->nodetype == LYS_CONTAINER && !((struct lyd_node_inner*)cur)->child &&
!cur->attr && !(((struct lysc_node_container*)cur->schema)->flags & LYS_PRESENCE)) {
cur->flags |= LYD_DEFAULT;
}
/* TODO context validation */
}
cleanup:
lyd_free_attr(ctx->ctx, attributes, 1);
return ret;
}
LY_ERR
lyd_parse_xml(struct ly_ctx *ctx, const char *data, int options, struct lyd_node **result)
{
LY_ERR ret;
struct lyd_xml_ctx xmlctx = {0};
xmlctx.options = options;
xmlctx.ctx = ctx;
xmlctx.line = 1;
ret = lydxml_nodes(&xmlctx, NULL, &data, result);
if (ret) {
lyd_free_all(*result);
*result = NULL;
} else {
/* finish incompletely validated terminal values */
for (unsigned int u = 0; u < xmlctx.incomplete_type_validation.count; u++) {
struct lyd_node_term *node = (struct lyd_node_term*)xmlctx.incomplete_type_validation.objs[u];
const struct lyd_node **trees = NULL;
/* prepare sized array for validator */
if (*result) {
trees = lyd_trees_new(1, *result);
}
/* validate and store the value of the node */
ret = lyd_value_parse(node, node->value.canonized, node->value.canonized ? strlen(node->value.canonized) : 0, 0, 1,
lydxml_resolve_prefix, ctx, LYD_XML, trees);
lyd_trees_free(trees, 0);
if (ret) {
lyd_free_all(*result);
*result = NULL;
break;
}
}
}
ly_set_erase(&xmlctx.incomplete_type_validation, NULL);
lyxml_context_clear((struct lyxml_context*)&xmlctx);
return ret;
}