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Diffstat (limited to 'external/unbound/util/regional.h')
| -rw-r--r-- | external/unbound/util/regional.h | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/external/unbound/util/regional.h b/external/unbound/util/regional.h new file mode 100644 index 000000000..e8b2cb8d0 --- /dev/null +++ b/external/unbound/util/regional.h @@ -0,0 +1,150 @@ +/* + * regional.h -- region based memory allocator. + * + * Copyright (c) 2007, NLnet Labs. All rights reserved. + * + * This software is open source. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * Neither the name of the NLNET LABS nor the names of its contributors may + * be used to endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED + * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR + * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/** + * \file + * Regional allocator. Allocates small portions of of larger chunks. + * Based on region-allocator from NSD, but rewritten to be light. + * + * Different from (nsd) region-allocator.h + * o does not have recycle bin + * o does not collect stats; just enough to answer get_mem() in use. + * o does not keep cleanup list + * o does not have function pointers to setup + * o allocs the regional struct inside the first block. + * o can take a block to create regional from. + * o blocks and large allocations are kept on singly linked lists. + */ + +#ifndef UTIL_REGIONAL_H_ +#define UTIL_REGIONAL_H_ + +/** + * the regional* is the first block*. + * every block has a ptr to the next in first bytes. + * and so does the regional struct, which is the first block. + */ +struct regional +{ + /** + * next chunk. NULL if first chunk is the only chunk. + * first inside that chunk is the char* next pointer. + * When regional_free_all() has been called this value is NULL. + */ + char* next; + /** first large object, cast to char** to obtain next ptr */ + char* large_list; + /** total large size */ + size_t total_large; + /** initial chunk size */ + size_t first_size; + /** number of bytes available in the current chunk. */ + size_t available; + /** current chunk data position. */ + char* data; +}; + +/** + * Create a new regional. + * @return: newly allocated regional. + */ +struct regional* regional_create(void); + +/** + * Create a new region, with custom settings. + * @param size: length of first block. + * @return: newly allocated regional. + */ +struct regional* regional_create_custom(size_t size); + +/** + * Free all memory associated with regional. Only keeps the first block with + * the regional inside it. + * @param r: the region. + */ +void regional_free_all(struct regional *r); + +/** + * Destroy regional. All memory associated with regional is freed as if + * regional_free_all was called, as well as destroying the regional struct. + * @param r: to delete. + */ +void regional_destroy(struct regional *r); + +/** + * Allocate size bytes of memory inside regional. The memory is + * deallocated when region_free_all is called for this region. + * @param r: the region. + * @param size: number of bytes. + * @return: pointer to memory allocated. + */ +void *regional_alloc(struct regional *r, size_t size); + +/** + * Allocate size bytes of memory inside regional and copy INIT into it. + * The memory is deallocated when region_free_all is called for this + * region. + * @param r: the region. + * @param init: to copy. + * @param size: number of bytes. + * @return: pointer to memory allocated. + */ +void *regional_alloc_init(struct regional* r, const void *init, size_t size); + +/** + * Allocate size bytes of memory inside regional that are initialized to + * 0. The memory is deallocated when region_free_all is called for + * this region. + * @param r: the region. + * @param size: number of bytes. + * @return: pointer to memory allocated. + */ +void *regional_alloc_zero(struct regional *r, size_t size); + +/** + * Duplicate string and allocate the result in regional. + * @param r: the region. + * @param string: null terminated string. + * @return: pointer to memory allocated. + */ +char *regional_strdup(struct regional *r, const char *string); + +/** Debug print regional statistics to log */ +void regional_log_stats(struct regional *r); + +/** get total memory size in use by region */ +size_t regional_get_mem(struct regional* r); + +#endif /* UTIL_REGIONAL_H_ */ |