regional.h revision 1.1.1.1.18.1
1 /* 2 * regional.h -- region based memory allocator. 3 * 4 * Copyright (c) 2007, NLnet Labs. All rights reserved. 5 * 6 * This software is open source. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 19 * Neither the name of the NLNET LABS nor the names of its contributors may 20 * be used to endorse or promote products derived from this software without 21 * specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 /** 37 * \file 38 * Regional allocator. Allocates small portions of of larger chunks. 39 * Based on region-allocator from NSD, but rewritten to be light. 40 * 41 * Different from (nsd) region-allocator.h 42 * o does not have recycle bin 43 * o does not collect stats; just enough to answer get_mem() in use. 44 * o does not keep cleanup list 45 * o does not have function pointers to setup 46 * o allocs the regional struct inside the first block. 47 * o can take a block to create regional from. 48 * o blocks and large allocations are kept on singly linked lists. 49 */ 50 51 #ifndef UTIL_REGIONAL_H_ 52 #define UTIL_REGIONAL_H_ 53 54 /** 55 * the regional* is the first block*. 56 * every block has a ptr to the next in first bytes. 57 * and so does the regional struct, which is the first block. 58 */ 59 struct regional 60 { 61 /** 62 * next chunk. NULL if first chunk is the only chunk. 63 * first inside that chunk is the char* next pointer. 64 * When regional_free_all() has been called this value is NULL. 65 */ 66 char* next; 67 /** first large object, cast to char** to obtain next ptr */ 68 char* large_list; 69 /** total large size */ 70 size_t total_large; 71 /** initial chunk size */ 72 size_t first_size; 73 /** number of bytes available in the current chunk. */ 74 size_t available; 75 /** current chunk data position. */ 76 char* data; 77 /** threshold for outside of chunk allocations */ 78 size_t large_object_size; 79 /** padding for sizeof8 alignment of sizeof(struct regional) 80 * for 32bit systems */ 81 size_t padding; 82 }; 83 84 /** 85 * Create a new regional. 86 * @return: newly allocated regional. 87 */ 88 struct regional* regional_create(void); 89 90 /** 91 * Create a new region, with custom settings. 92 * @param size: length of first block. 93 * @return: newly allocated regional. 94 */ 95 struct regional* regional_create_custom(size_t size); 96 97 /** 98 * Create a new region, with custom settings, that will allocate everything 99 * outside the region chunk. 100 * @param size: length of first block. 101 * @return: newly allocated regional. 102 */ 103 struct regional* regional_create_nochunk(size_t size); 104 105 /** 106 * Free all memory associated with regional. Only keeps the first block with 107 * the regional inside it. 108 * @param r: the region. 109 */ 110 void regional_free_all(struct regional *r); 111 112 /** 113 * Destroy regional. All memory associated with regional is freed as if 114 * regional_free_all was called, as well as destroying the regional struct. 115 * @param r: to delete. 116 */ 117 void regional_destroy(struct regional *r); 118 119 /** 120 * Allocate size bytes of memory inside regional. The memory is 121 * deallocated when region_free_all is called for this region. 122 * @param r: the region. 123 * @param size: number of bytes. 124 * @return: pointer to memory allocated. 125 */ 126 void *regional_alloc(struct regional *r, size_t size); 127 128 /** 129 * Allocate size bytes of memory inside regional and copy INIT into it. 130 * The memory is deallocated when region_free_all is called for this 131 * region. 132 * @param r: the region. 133 * @param init: to copy. 134 * @param size: number of bytes. 135 * @return: pointer to memory allocated. 136 */ 137 void *regional_alloc_init(struct regional* r, const void *init, size_t size); 138 139 /** 140 * Allocate size bytes of memory inside regional that are initialized to 141 * 0. The memory is deallocated when region_free_all is called for 142 * this region. 143 * @param r: the region. 144 * @param size: number of bytes. 145 * @return: pointer to memory allocated. 146 */ 147 void *regional_alloc_zero(struct regional *r, size_t size); 148 149 /** 150 * Duplicate string and allocate the result in regional. 151 * @param r: the region. 152 * @param string: null terminated string. 153 * @return: pointer to memory allocated. 154 */ 155 char *regional_strdup(struct regional *r, const char *string); 156 157 /** Debug print regional statistics to log */ 158 void regional_log_stats(struct regional *r); 159 160 /** get total memory size in use by region */ 161 size_t regional_get_mem(struct regional* r); 162 163 #endif /* UTIL_REGIONAL_H_ */ 164
Indexes created Tue Jul 07 00:25:39 UTC 2026