blob: ac5e4b077610ff0255aeab0fcc77a9859056b493 [file] [log] [blame]
/**
* @file tree_edit.h
* @author Radek Krejci <rkrejci@cesnet.cz>
* @brief libyang generic macros and functions to modify YANG schema or data trees. Intended for internal use and libyang
* plugins.
*
* Copyright (c) 2019-2021 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
*/
#ifndef LY_TREE_EDIT_H_
#define LY_TREE_EDIT_H_
#include <stdlib.h>
#include "log.h"
#include "tree.h"
#ifndef LOGMEM
#define LOGMEM(CTX)
#endif
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief Wrapper for realloc() call. The only difference is that if it fails to
* allocate the requested memory, the original memory is freed as well.
*
* @param[in] ptr Memory to reallocate.
* @param[in] size New size of the memory block.
*
* @return Pointer to the new memory, NULL on error.
*/
void *ly_realloc(void *ptr, size_t size);
/**
* @defgroup trees_edit Trees - modification
* @ingroup trees
*
* Generic macros, functions, etc. to modify [schema](@ref schematree) and [data](@ref datatree) trees.
* @{
*/
/**
* @brief (Re-)Allocation of a ([sized array](@ref sizedarrays)).
*
* Increases the size information.
*
* This is a generic macro for ::LY_ARRAY_NEW_RET and ::LY_ARRAY_NEW_GOTO.
*
* @param[in] CTX libyang context for logging.
* @param[in,out] ARRAY Pointer to the array to allocate/resize. The size of the allocated
* space is counted from the type of the ARRAY, so do not provide placeholder void pointers.
* @param[in] EACTION Action to perform in case of error (memory allocation failure).
*/
#define LY_ARRAY_NEW(CTX, ARRAY, EACTION) \
{ \
void *p__; \
if (ARRAY) { \
++(*((LY_ARRAY_COUNT_TYPE*)(ARRAY) - 1)); \
p__ = realloc(((LY_ARRAY_COUNT_TYPE*)(ARRAY) - 1), \
sizeof(LY_ARRAY_COUNT_TYPE) + (*((LY_ARRAY_COUNT_TYPE*)(ARRAY) - 1) * sizeof *(ARRAY))); \
if (!p__) { \
--(*((LY_ARRAY_COUNT_TYPE*)(p__) - 1)); \
LOGMEM(CTX); \
EACTION; \
} \
} else { \
p__ = malloc(sizeof(LY_ARRAY_COUNT_TYPE) + sizeof *(ARRAY)); \
if (!p__) { \
LOGMEM(CTX); \
EACTION; \
} \
*((LY_ARRAY_COUNT_TYPE*)(p__)) = 1; \
} \
p__ = (void*)((LY_ARRAY_COUNT_TYPE*)(p__) + 1); \
memcpy(&(ARRAY), &p__, sizeof p__); \
}
/**
* @brief (Re-)Allocation of a ([sized array](@ref sizedarrays)).
*
* Increases the size information.
*
* @param[in] CTX libyang context for logging.
* @param[in,out] ARRAY Pointer to the array to allocate/resize. The size of the allocated
* space is counted from the type of the ARRAY, so do not provide placeholder void pointers.
* @param[out] NEW_ITEM Returning pointer to the newly allocated record in the ARRAY.
* @param[in] RETVAL Return value for the case of error (memory allocation failure).
*/
#define LY_ARRAY_NEW_RET(CTX, ARRAY, NEW_ITEM, RETVAL) \
LY_ARRAY_NEW(CTX, ARRAY, return RETVAL); \
(NEW_ITEM) = &(ARRAY)[*((LY_ARRAY_COUNT_TYPE*)(ARRAY) - 1) - 1]; \
memset(NEW_ITEM, 0, sizeof *(NEW_ITEM))
/**
* @brief (Re-)Allocation of a ([sized array](@ref sizedarrays)).
*
* Increases the size information.
*
* @param[in] CTX libyang context for logging.
* @param[in,out] ARRAY Pointer to the array to allocate/resize. The size of the allocated
* space is counted from the type of the ARRAY, so do not provide placeholder void pointers.
* @param[out] NEW_ITEM Returning pointer to the newly allocated record in the ARRAY.
* @param[out] RET Variable to store error code.
* @param[in] GOTO Label to go in case of error (memory allocation failure).
*/
#define LY_ARRAY_NEW_GOTO(CTX, ARRAY, NEW_ITEM, RET, GOTO) \
LY_ARRAY_NEW(CTX, ARRAY, RET = LY_EMEM; goto GOTO); \
(NEW_ITEM) = &(ARRAY)[*((LY_ARRAY_COUNT_TYPE*)(ARRAY) - 1) - 1]; \
memset(NEW_ITEM, 0, sizeof *(NEW_ITEM))
/**
* @brief Allocate a ([sized array](@ref sizedarrays)) for the specified number of items.
* If the ARRAY already exists, it is resized (space for SIZE items is added and zeroed).
*
* Does not set the size information, it is supposed to be incremented via ::LY_ARRAY_INCREMENT
* when the items are filled.
*
* This is a generic macro for ::LY_ARRAY_CREATE_RET and ::LY_ARRAY_CREATE_GOTO.
*
* @param[in] CTX libyang context for logging.
* @param[in,out] ARRAY Pointer to the array to create.
* @param[in] SIZE Number of the new items the array is supposed to hold. The size of the allocated
* space is then counted from the type of the ARRAY, so do not provide placeholder void pointers.
* @param[in] EACTION Action to perform in case of error (memory allocation failure).
*/
#define LY_ARRAY_CREATE(CTX, ARRAY, SIZE, EACTION) \
{ \
void *p__; \
if (ARRAY) { \
p__ = realloc(((LY_ARRAY_COUNT_TYPE*)(ARRAY) - 1), \
sizeof(LY_ARRAY_COUNT_TYPE) + ((*((LY_ARRAY_COUNT_TYPE*)(ARRAY) - 1) + (SIZE)) * sizeof *(ARRAY))); \
if (!p__) { \
LOGMEM(CTX); \
EACTION; \
} \
} else { \
p__ = calloc(1, sizeof(LY_ARRAY_COUNT_TYPE) + (SIZE) * sizeof *(ARRAY)); \
if (!p__) { \
LOGMEM(CTX); \
EACTION; \
} \
} \
p__ = (void*)((LY_ARRAY_COUNT_TYPE*)(p__) + 1); \
memcpy(&(ARRAY), &p__, sizeof p__); \
if (ARRAY) { \
memset(&(ARRAY)[*((LY_ARRAY_COUNT_TYPE*)(p__) - 1)], 0, (SIZE) * sizeof *(ARRAY)); \
} \
}
/**
* @brief Allocate a ([sized array](@ref sizedarrays)) for the specified number of items.
* If the ARRAY already exists, it is resized (space for SIZE items is added and zeroed).
*
* Does not set the size information, it is supposed to be incremented via ::LY_ARRAY_INCREMENT
* when the items are filled.
*
* @param[in] CTX libyang context for logging.
* @param[in,out] ARRAY Pointer to the array to create.
* @param[in] SIZE Number of the new items the array is supposed to hold. The size of the allocated
* space is then counted from the type of the ARRAY, so do not provide placeholder void pointers.
* @param[in] RETVAL Return value for the case of error (memory allocation failure).
*/
#define LY_ARRAY_CREATE_RET(CTX, ARRAY, SIZE, RETVAL) \
LY_ARRAY_CREATE(CTX, ARRAY, SIZE, return RETVAL)
/**
* @brief Allocate a ([sized array](@ref sizedarrays)) for the specified number of items.
* If the ARRAY already exists, it is resized (space for SIZE items is added).
*
* Does not set the count information, it is supposed to be incremented via ::LY_ARRAY_INCREMENT
* when the items are filled.
*
* @param[in] CTX libyang context for logging.
* @param[in,out] ARRAY Pointer to the array to create.
* @param[in] SIZE Number of the new items the array is supposed to hold. The size of the allocated
* space is then counted from the type of the ARRAY, so do not provide placeholder void pointers.
* @param[out] RET Variable to store error code.
* @param[in] GOTO Label to go in case of error (memory allocation failure).
*/
#define LY_ARRAY_CREATE_GOTO(CTX, ARRAY, SIZE, RET, GOTO) \
LY_ARRAY_CREATE(CTX, ARRAY, SIZE, RET = LY_EMEM; goto GOTO)
/**
* @brief Increment the items counter in a ([sized array](@ref sizedarrays)).
*
* Does not change the allocated memory used by the ARRAY. To do so, use LY_ARRAY_CREATE_RET,
* LY_ARRAY_CREATE_GOTO or LY_ARRAY_RESIZE_ERR_RET.
*
* @param[in] ARRAY Pointer to the array to affect.
*/
#define LY_ARRAY_INCREMENT(ARRAY) \
++(*((LY_ARRAY_COUNT_TYPE*)(ARRAY) - 1))
/**
* @brief Decrement the items counter in a ([sized array](@ref sizedarrays)).
*
* Does not change the allocated memory used by the ARRAY. To do so, use LY_ARRAY_CREATE_RET,
* LY_ARRAY_CREATE_GOTO or LY_ARRAY_RESIZE_ERR_RET.
*
* @param[in] ARRAY Pointer to the array to affect.
*/
#define LY_ARRAY_DECREMENT(ARRAY) \
--(*((LY_ARRAY_COUNT_TYPE*)(ARRAY) - 1))
/**
* @brief Decrement the items counter in a ([sized array](@ref sizedarrays)) and free the whole array
* in case it was decremented to 0.
*
* @param[in] ARRAY Pointer to the array to affect.
*/
#define LY_ARRAY_DECREMENT_FREE(ARRAY) \
--(*((LY_ARRAY_COUNT_TYPE*)(ARRAY) - 1)); \
if (!LY_ARRAY_COUNT(ARRAY)) { \
LY_ARRAY_FREE(ARRAY); \
(ARRAY) = NULL; \
}
/**
* @brief Free the space allocated for the ([sized array](@ref sizedarrays)).
*
* The items inside the array are not freed.
*
* @param[in] ARRAY A ([sized array](@ref sizedarrays)) to be freed.
*/
#define LY_ARRAY_FREE(ARRAY) \
if (ARRAY){free((LY_ARRAY_COUNT_TYPE*)(ARRAY) - 1);}
/**
* @brief Insert item into linked list.
*
* @param[in,out] LIST Linked list to add to.
* @param[in] NEW_ITEM New item, that will be appended to the list, must be already allocated.
* @param[in] LINKER name of structuin member that is used to connect items together.
*/
#define LY_LIST_INSERT(LIST, NEW_ITEM, LINKER)\
if (!(*LIST)) { \
memcpy(LIST, &(NEW_ITEM), sizeof NEW_ITEM); \
} else { \
size_t offset__ = (void*)&(*LIST)->LINKER - (void*)(*LIST); \
void **iter__ = (void **)((size_t)(*LIST) + offset__); \
while (*iter__) { \
iter__ = (void **)((size_t)(*iter__) + offset__); \
} \
memcpy(iter__, &(NEW_ITEM), sizeof NEW_ITEM); \
}
/**
* @brief Allocate and insert new item into linked list, return in case of error.
*
* This is a generic macro for ::LY_LIST_NEW_RET and ::LY_LIST_NEW_GOTO.
*
* @param[in] CTX used for logging.
* @param[in,out] LIST Linked list to add to.
* @param[out] NEW_ITEM New item that is appended to the list.
* @param[in] LINKER name of structure member that is used to connect items together.
* @param[in] EACTION Action to perform in case of error (memory allocation failure).
*/
#define LY_LIST_NEW(CTX, LIST, NEW_ITEM, LINKER, EACTION) \
{ \
void *p__ = calloc(1, sizeof *NEW_ITEM); \
if (!p__) { \
LOGMEM(CTX); \
EACTION; \
} \
memcpy(&(NEW_ITEM), &p__, sizeof p__); \
LY_LIST_INSERT(LIST, NEW_ITEM, LINKER); \
}
/**
* @brief Allocate and insert new item into linked list, return in case of error.
*
* @param[in] CTX used for logging.
* @param[in,out] LIST Linked list to add to.
* @param[out] NEW_ITEM New item that is appended to the list.
* @param[in] LINKER name of structure member that is used to connect items together.
* @param[in] RETVAL Return value for the case of error (memory allocation failure).
*/
#define LY_LIST_NEW_RET(CTX, LIST, NEW_ITEM, LINKER, RETVAL) \
LY_LIST_NEW(CTX, LIST, NEW_ITEM, LINKER, return RETVAL)
/**
* @brief Allocate and insert new item into linked list, goto specified label in case of error.
*
* @param[in] CTX used for logging.
* @param[in,out] LIST Linked list to add to.
* @param[out] NEW_ITEM New item that is appended to the list.
* @param[in] LINKER name of structure member that is used to connect items together.
* @param[in] RET variable to store returned error type.
* @param[in] LABEL label to goto in case of error.
*/
#define LY_LIST_NEW_GOTO(CTX, LIST, NEW_ITEM, LINKER, RET, LABEL) \
LY_LIST_NEW(CTX, LIST, NEW_ITEM, LINKER, RET = LY_EMEM; goto LABEL)
/** @} trees_edit */
#ifdef __cplusplus
}
#endif
#endif /* LY_TREE_EDIT_H_ */