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Diffstat (limited to '')
-rw-r--r-- | src/plugins_types/xpath1.0.c | 521 |
1 files changed, 521 insertions, 0 deletions
diff --git a/src/plugins_types/xpath1.0.c b/src/plugins_types/xpath1.0.c new file mode 100644 index 0000000..a15e5b7 --- /dev/null +++ b/src/plugins_types/xpath1.0.c @@ -0,0 +1,521 @@ +/** + * @file xpath1.0.c + * @author Michal Vasko <mvasko@cesnet.cz> + * @brief ietf-yang-types xpath1.0 type plugin. + * + * Copyright (c) 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 + +#include "plugins_types.h" + +#include <assert.h> +#include <stdint.h> +#include <stdlib.h> +#include <string.h> + +#include "libyang.h" + +#include "common.h" +#include "compat.h" + +/* internal headers */ +#include "xml.h" +#include "xpath.h" + +/** + * @page howtoDataLYB LYB Binary Format + * @subsection howtoDataLYBTypesXpath10 xpath1.0 (ietf-yang-types) + * + * | Size (B) | Mandatory | Type | Meaning | + * | :------ | :-------: | :--: | :-----: | + * | string length | yes | `char *` | string JSON format of the XPath expression | + */ + +LIBYANG_API_DEF LY_ERR +lyplg_type_xpath10_print_token(const char *token, uint16_t tok_len, ly_bool is_nametest, const struct lys_module **context_mod, + const struct ly_ctx *resolve_ctx, LY_VALUE_FORMAT resolve_format, const void *resolve_prefix_data, + LY_VALUE_FORMAT get_format, void *get_prefix_data, char **token_p, struct ly_err_item **err) +{ + LY_ERR ret = LY_SUCCESS; + const char *str_begin, *str_next, *prefix; + ly_bool is_prefix, has_prefix = 0; + char *str = NULL; + void *mem; + uint32_t len, str_len = 0, pref_len; + const struct lys_module *mod; + + str_begin = token; + + while (!(ret = ly_value_prefix_next(str_begin, token + tok_len, &len, &is_prefix, &str_next)) && len) { + if (!is_prefix) { + if (!has_prefix && is_nametest && (get_format == LY_VALUE_XML) && *context_mod) { + /* prefix is always needed, get it in the target format */ + prefix = lyplg_type_get_prefix(*context_mod, get_format, get_prefix_data); + if (!prefix) { + ret = ly_err_new(err, LY_EINT, LYVE_DATA, NULL, NULL, "Internal error."); + goto cleanup; + } + + /* append the nametest and prefix */ + mem = realloc(str, str_len + strlen(prefix) + 1 + len + 1); + LY_CHECK_ERR_GOTO(!mem, ret = ly_err_new(err, LY_EMEM, LYVE_DATA, NULL, NULL, "No memory."), cleanup); + str = mem; + str_len += sprintf(str + str_len, "%s:%.*s", prefix, len, str_begin); + } else { + /* just append the string, we may get the first expression node without a prefix but since this + * is not strictly forbidden, allow it */ + mem = realloc(str, str_len + len + 1); + LY_CHECK_ERR_GOTO(!mem, ret = ly_err_new(err, LY_EMEM, LYVE_DATA, NULL, NULL, "No memory."), cleanup); + str = mem; + str_len += sprintf(str + str_len, "%.*s", len, str_begin); + } + } else { + /* remember there was a prefix found */ + has_prefix = 1; + + /* resolve the module in the original format */ + mod = lyplg_type_identity_module(resolve_ctx, NULL, str_begin, len, resolve_format, resolve_prefix_data); + if (!mod && is_nametest) { + ret = ly_err_new(err, LY_EVALID, LYVE_DATA, NULL, NULL, "Failed to resolve prefix \"%.*s\".", len, str_begin); + goto cleanup; + } + + if (is_nametest && ((get_format == LY_VALUE_JSON) || (get_format == LY_VALUE_LYB)) && (*context_mod == mod)) { + /* inherit the prefix and do not print it again */ + } else { + if (mod) { + /* get the prefix in the target format */ + prefix = lyplg_type_get_prefix(mod, get_format, get_prefix_data); + if (!prefix) { + ret = ly_err_new(err, LY_EINT, LYVE_DATA, NULL, NULL, "Internal error."); + goto cleanup; + } + pref_len = strlen(prefix); + } else { + /* invalid prefix, just copy it */ + prefix = str_begin; + pref_len = len; + } + + /* append the prefix */ + mem = realloc(str, str_len + pref_len + 2); + LY_CHECK_ERR_GOTO(!mem, ret = ly_err_new(err, LY_EMEM, LYVE_DATA, NULL, NULL, "No memory."), cleanup); + str = mem; + str_len += sprintf(str + str_len, "%.*s:", (int)pref_len, prefix); + } + + if (is_nametest) { + /* update context module */ + *context_mod = mod; + } + } + + str_begin = str_next; + } + +cleanup: + if (ret) { + free(str); + } else { + *token_p = str; + } + return ret; +} + +/** + * @brief Print xpath1.0 subexpression in the specific format. + * + * @param[in,out] cur_idx Current index of the next token in the expression. + * @param[in] end_tok End token (including) that finishes this subexpression parsing. If 0, parse until the end. + * @param[in] context_mod Current context module, some formats (::LY_VALUE_JSON and ::LY_VALUE_LYB) inherit this module + * instead of printing it again. + * @param[in] xp_val xpath1.0 value structure. + * @param[in] format Format to print in. + * @param[in] prefix_data Format-specific prefix data. + * @param[in,out] str_value Printed value, appended to. + * @param[in,out] str_len Length of @p str_value, updated. + * @param[out] err Error structure on error. + * @return LY_ERR value. + */ +static LY_ERR +xpath10_print_subexpr_r(uint16_t *cur_idx, enum lyxp_token end_tok, const struct lys_module *context_mod, + const struct lyd_value_xpath10 *xp_val, LY_VALUE_FORMAT format, void *prefix_data, char **str_value, + uint32_t *str_len, struct ly_err_item **err) +{ + enum lyxp_token cur_tok, sub_end_tok; + char *str_tok; + void *mem; + const char *cur_exp_ptr; + ly_bool is_nt; + const struct lys_module *orig_context_mod = context_mod; + + while (*cur_idx < xp_val->exp->used) { + cur_tok = xp_val->exp->tokens[*cur_idx]; + cur_exp_ptr = xp_val->exp->expr + xp_val->exp->tok_pos[*cur_idx]; + + if ((cur_tok == LYXP_TOKEN_NAMETEST) || (cur_tok == LYXP_TOKEN_LITERAL)) { + /* tokens that may include prefixes, get them in the target format */ + is_nt = (cur_tok == LYXP_TOKEN_NAMETEST) ? 1 : 0; + LY_CHECK_RET(lyplg_type_xpath10_print_token(cur_exp_ptr, xp_val->exp->tok_len[*cur_idx], is_nt, &context_mod, + xp_val->ctx, xp_val->format, xp_val->prefix_data, format, prefix_data, &str_tok, err)); + + /* append the converted token */ + mem = realloc(*str_value, *str_len + strlen(str_tok) + 1); + LY_CHECK_ERR_GOTO(!mem, free(str_tok), error_mem); + *str_value = mem; + *str_len += sprintf(*str_value + *str_len, "%s", str_tok); + free(str_tok); + + /* token processed */ + ++(*cur_idx); + } else { + if ((cur_tok == LYXP_TOKEN_OPER_LOG) || (cur_tok == LYXP_TOKEN_OPER_UNI) || (cur_tok == LYXP_TOKEN_OPER_MATH)) { + /* copy the token with spaces around */ + mem = realloc(*str_value, *str_len + 1 + xp_val->exp->tok_len[*cur_idx] + 2); + LY_CHECK_GOTO(!mem, error_mem); + *str_value = mem; + *str_len += sprintf(*str_value + *str_len, " %.*s ", (int)xp_val->exp->tok_len[*cur_idx], cur_exp_ptr); + + /* reset context mod */ + context_mod = orig_context_mod; + } else { + /* just copy the token */ + mem = realloc(*str_value, *str_len + xp_val->exp->tok_len[*cur_idx] + 1); + LY_CHECK_GOTO(!mem, error_mem); + *str_value = mem; + *str_len += sprintf(*str_value + *str_len, "%.*s", (int)xp_val->exp->tok_len[*cur_idx], cur_exp_ptr); + } + + /* token processed but keep it in cur_tok */ + ++(*cur_idx); + + if (end_tok && (cur_tok == end_tok)) { + /* end token found */ + break; + } else if ((cur_tok == LYXP_TOKEN_BRACK1) || (cur_tok == LYXP_TOKEN_PAR1)) { + sub_end_tok = (cur_tok == LYXP_TOKEN_BRACK1) ? LYXP_TOKEN_BRACK2 : LYXP_TOKEN_PAR2; + + /* parse the subexpression separately, use the current context mod */ + LY_CHECK_RET(xpath10_print_subexpr_r(cur_idx, sub_end_tok, context_mod, xp_val, format, prefix_data, + str_value, str_len, err)); + } + } + } + + return LY_SUCCESS; + +error_mem: + return ly_err_new(err, LY_EMEM, LYVE_DATA, NULL, NULL, "No memory."); +} + +LIBYANG_API_DEF LY_ERR +lyplg_type_print_xpath10_value(const struct lyd_value_xpath10 *xp_val, LY_VALUE_FORMAT format, void *prefix_data, + char **str_value, struct ly_err_item **err) +{ + LY_ERR ret = LY_SUCCESS; + uint16_t expr_idx = 0; + uint32_t str_len = 0; + + *str_value = NULL; + *err = NULL; + + /* recursively print the expression */ + ret = xpath10_print_subexpr_r(&expr_idx, 0, NULL, xp_val, format, prefix_data, str_value, &str_len, err); + + if (ret) { + free(*str_value); + *str_value = NULL; + } + return ret; +} + +LIBYANG_API_DEF LY_ERR +lyplg_type_store_xpath10(const struct ly_ctx *ctx, const struct lysc_type *type, const void *value, size_t value_len, + uint32_t options, LY_VALUE_FORMAT format, void *prefix_data, uint32_t hints, const struct lysc_node *ctx_node, + struct lyd_value *storage, struct lys_glob_unres *UNUSED(unres), struct ly_err_item **err) +{ + LY_ERR ret = LY_SUCCESS; + struct lysc_type_str *type_str = (struct lysc_type_str *)type; + struct lyd_value_xpath10 *val; + char *canon; + + /* init storage */ + memset(storage, 0, sizeof *storage); + LYPLG_TYPE_VAL_INLINE_PREPARE(storage, val); + LY_CHECK_ERR_GOTO(!val, ret = LY_EMEM, cleanup); + storage->realtype = type; + + /* check hints */ + ret = lyplg_type_check_hints(hints, value, value_len, type->basetype, NULL, err); + LY_CHECK_GOTO(ret, cleanup); + + /* length restriction of the string */ + if (type_str->length) { + /* value_len is in bytes, but we need number of characters here */ + ret = lyplg_type_validate_range(LY_TYPE_STRING, type_str->length, ly_utf8len(value, value_len), value, value_len, err); + LY_CHECK_GOTO(ret, cleanup); + } + + /* pattern restrictions */ + ret = lyplg_type_validate_patterns(type_str->patterns, value, value_len, err); + LY_CHECK_GOTO(ret, cleanup); + + /* parse */ + ret = lyxp_expr_parse(ctx, value_len ? value : "", value_len, 1, &val->exp); + LY_CHECK_GOTO(ret, cleanup); + val->ctx = ctx; + + if (ctx_node && !strcmp(ctx_node->name, "parent-reference") && !strcmp(ctx_node->module->name, "ietf-yang-schema-mount")) { + /* special case, this type uses prefix-namespace mapping provided directly in data, keep empty for now */ + val->format = format = LY_VALUE_STR_NS; + ret = ly_set_new((struct ly_set **)&val->prefix_data); + LY_CHECK_GOTO(ret, cleanup); + } else { + /* store format-specific data and context for later prefix resolution */ + ret = lyplg_type_prefix_data_new(ctx, value, value_len, format, prefix_data, &val->format, &val->prefix_data); + LY_CHECK_GOTO(ret, cleanup); + } + + switch (format) { + case LY_VALUE_CANON: + case LY_VALUE_JSON: + case LY_VALUE_LYB: + case LY_VALUE_STR_NS: + /* store canonical value */ + if (options & LYPLG_TYPE_STORE_DYNAMIC) { + ret = lydict_insert_zc(ctx, (char *)value, &storage->_canonical); + options &= ~LYPLG_TYPE_STORE_DYNAMIC; + LY_CHECK_GOTO(ret, cleanup); + } else { + ret = lydict_insert(ctx, value_len ? value : "", value_len, &storage->_canonical); + LY_CHECK_GOTO(ret, cleanup); + } + break; + case LY_VALUE_SCHEMA: + case LY_VALUE_SCHEMA_RESOLVED: + case LY_VALUE_XML: + /* JSON format with prefix is the canonical one */ + ret = lyplg_type_print_xpath10_value(val, LY_VALUE_JSON, NULL, &canon, err); + LY_CHECK_GOTO(ret, cleanup); + + ret = lydict_insert_zc(ctx, canon, &storage->_canonical); + LY_CHECK_GOTO(ret, cleanup); + break; + } + +cleanup: + if (options & LYPLG_TYPE_STORE_DYNAMIC) { + free((void *)value); + } + + if (ret) { + lyplg_type_free_xpath10(ctx, storage); + } else if (val->format == LY_VALUE_STR_NS) { + /* needs validation */ + return LY_EINCOMPLETE; + } + return ret; +} + +/** + * @brief Implementation of ::lyplg_type_validate_clb for the xpath1.0 ietf-yang-types type. + */ +static LY_ERR +lyplg_type_validate_xpath10(const struct ly_ctx *UNUSED(ctx), const struct lysc_type *UNUSED(type), + const struct lyd_node *ctx_node, const struct lyd_node *UNUSED(tree), struct lyd_value *storage, + struct ly_err_item **err) +{ + LY_ERR ret = LY_SUCCESS; + struct lyd_value_xpath10 *val; + struct ly_set *set = NULL; + uint32_t i; + const char *pref, *uri; + struct lyxml_ns *ns; + + *err = NULL; + LYD_VALUE_GET(storage, val); + + if (val->format != LY_VALUE_STR_NS) { + /* nothing to validate */ + return LY_SUCCESS; + } + + /* the XML namespace set must exist */ + assert(val->prefix_data); + + /* special handling of this particular node */ + assert(!strcmp(LYD_NAME(ctx_node), "parent-reference") && + !strcmp(ctx_node->schema->module->name, "ietf-yang-schema-mount")); + + /* get all the prefix mappings */ + if ((ret = lyd_find_xpath(ctx_node, "../../../namespace", &set))) { + goto cleanup; + } + + for (i = 0; i < set->count; ++i) { + assert(!strcmp(LYD_NAME(lyd_child(set->dnodes[i])), "prefix")); + pref = lyd_get_value(lyd_child(set->dnodes[i])); + + if (!lyd_child(set->dnodes[i])->next) { + /* missing URI - invalid mapping, skip */ + continue; + } + assert(!strcmp(LYD_NAME(lyd_child(set->dnodes[i])->next), "uri")); + uri = lyd_get_value(lyd_child(set->dnodes[i])->next); + + /* create new ns */ + ns = calloc(1, sizeof *ns); + if (!ns) { + ret = LY_EMEM; + goto cleanup; + } + ns->prefix = strdup(pref); + ns->uri = strdup(uri); + if (!ns->prefix || !ns->uri) { + free(ns->prefix); + free(ns->uri); + free(ns); + ret = LY_EMEM; + goto cleanup; + } + ns->depth = 1; + + /* add into the XML namespace set */ + if ((ret = ly_set_add(val->prefix_data, ns, 1, NULL))) { + free(ns->prefix); + free(ns->uri); + free(ns); + goto cleanup; + } + } + +cleanup: + ly_set_free(set, NULL); + if (ret == LY_EMEM) { + ly_err_new(err, LY_EMEM, LYVE_DATA, NULL, NULL, LY_EMEM_MSG); + } else if (ret) { + ly_err_new(err, ret, LYVE_DATA, NULL, NULL, "%s", ly_errmsg(LYD_CTX(ctx_node))); + } + return ret; +} + +LIBYANG_API_DEF const void * +lyplg_type_print_xpath10(const struct ly_ctx *ctx, const struct lyd_value *value, LY_VALUE_FORMAT format, + void *prefix_data, ly_bool *dynamic, size_t *value_len) +{ + struct lyd_value_xpath10 *val; + char *ret; + struct ly_err_item *err = NULL; + + LYD_VALUE_GET(value, val); + + /* LY_VALUE_STR_NS should never be transformed */ + if ((val->format == LY_VALUE_STR_NS) || (format == LY_VALUE_CANON) || (format == LY_VALUE_JSON) || + (format == LY_VALUE_LYB)) { + /* canonical */ + if (dynamic) { + *dynamic = 0; + } + if (value_len) { + *value_len = strlen(value->_canonical); + } + return value->_canonical; + } + + /* print in the specific format */ + if (lyplg_type_print_xpath10_value(val, format, prefix_data, &ret, &err)) { + if (err) { + LOGVAL_ERRITEM(ctx, err); + ly_err_free(err); + } + return NULL; + } + + *dynamic = 1; + if (value_len) { + *value_len = strlen(ret); + } + return ret; +} + +LIBYANG_API_DEF LY_ERR +lyplg_type_dup_xpath10(const struct ly_ctx *ctx, const struct lyd_value *original, struct lyd_value *dup) +{ + LY_ERR ret = LY_SUCCESS; + struct lyd_value_xpath10 *orig_val, *dup_val; + + /* init dup value */ + memset(dup, 0, sizeof *dup); + dup->realtype = original->realtype; + + ret = lydict_insert(ctx, original->_canonical, 0, &dup->_canonical); + LY_CHECK_GOTO(ret, cleanup); + + LYPLG_TYPE_VAL_INLINE_PREPARE(dup, dup_val); + LY_CHECK_ERR_GOTO(!dup_val, LOGMEM(ctx); ret = LY_EMEM, cleanup); + dup_val->ctx = ctx; + + LYD_VALUE_GET(original, orig_val); + ret = lyxp_expr_dup(ctx, orig_val->exp, 0, 0, &dup_val->exp); + LY_CHECK_GOTO(ret, cleanup); + + ret = lyplg_type_prefix_data_dup(ctx, orig_val->format, orig_val->prefix_data, &dup_val->prefix_data); + LY_CHECK_GOTO(ret, cleanup); + dup_val->format = orig_val->format; + +cleanup: + if (ret) { + lyplg_type_free_xpath10(ctx, dup); + } + return ret; +} + +LIBYANG_API_DEF void +lyplg_type_free_xpath10(const struct ly_ctx *ctx, struct lyd_value *value) +{ + struct lyd_value_xpath10 *val; + + lydict_remove(ctx, value->_canonical); + value->_canonical = NULL; + LYD_VALUE_GET(value, val); + if (val) { + lyxp_expr_free(ctx, val->exp); + lyplg_type_prefix_data_free(val->format, val->prefix_data); + + LYPLG_TYPE_VAL_INLINE_DESTROY(val); + } +} + +/** + * @brief Plugin information for xpath1.0 type implementation. + * + * Note that external plugins are supposed to use: + * + * LYPLG_TYPES = { + */ +const struct lyplg_type_record plugins_xpath10[] = { + { + .module = "ietf-yang-types", + .revision = "2013-07-15", + .name = "xpath1.0", + + .plugin.id = "libyang 2 - xpath1.0, version 1", + .plugin.store = lyplg_type_store_xpath10, + .plugin.validate = lyplg_type_validate_xpath10, + .plugin.compare = lyplg_type_compare_simple, + .plugin.sort = NULL, + .plugin.print = lyplg_type_print_xpath10, + .plugin.duplicate = lyplg_type_dup_xpath10, + .plugin.free = lyplg_type_free_xpath10, + .plugin.lyb_data_len = -1, + }, + {0} +}; 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