midl.h revision 1.1.1.1.10.1
1 /* $NetBSD: midl.h,v 1.1.1.1.10.1 2017/03/20 06:56:14 pgoyette Exp $ */ 2 3 /** @file midl.h 4 * @brief LMDB ID List header file. 5 * 6 * This file was originally part of back-bdb but has been 7 * modified for use in libmdb. Most of the macros defined 8 * in this file are unused, just left over from the original. 9 * 10 * This file is only used internally in libmdb and its definitions 11 * are not exposed publicly. 12 */ 13 /* $OpenLDAP$ */ 14 /* This work is part of OpenLDAP Software <http://www.openldap.org/>. 15 * 16 * Copyright 2000-2016 The OpenLDAP Foundation. 17 * All rights reserved. 18 * 19 * Redistribution and use in source and binary forms, with or without 20 * modification, are permitted only as authorized by the OpenLDAP 21 * Public License. 22 * 23 * A copy of this license is available in the file LICENSE in the 24 * top-level directory of the distribution or, alternatively, at 25 * <http://www.OpenLDAP.org/license.html>. 26 */ 27 28 #ifndef _MDB_MIDL_H_ 29 #define _MDB_MIDL_H_ 30 31 #include <stddef.h> 32 33 #ifdef __cplusplus 34 extern "C" { 35 #endif 36 37 /** @defgroup internal LMDB Internals 38 * @{ 39 */ 40 41 /** @defgroup idls ID List Management 42 * @{ 43 */ 44 /** A generic unsigned ID number. These were entryIDs in back-bdb. 45 * Preferably it should have the same size as a pointer. 46 */ 47 typedef size_t MDB_ID; 48 49 /** An IDL is an ID List, a sorted array of IDs. The first 50 * element of the array is a counter for how many actual 51 * IDs are in the list. In the original back-bdb code, IDLs are 52 * sorted in ascending order. For libmdb IDLs are sorted in 53 * descending order. 54 */ 55 typedef MDB_ID *MDB_IDL; 56 57 /* IDL sizes - likely should be even bigger 58 * limiting factors: sizeof(ID), thread stack size 59 */ 60 #define MDB_IDL_LOGN 16 /* DB_SIZE is 2^16, UM_SIZE is 2^17 */ 61 #define MDB_IDL_DB_SIZE (1<<MDB_IDL_LOGN) 62 #define MDB_IDL_UM_SIZE (1<<(MDB_IDL_LOGN+1)) 63 64 #define MDB_IDL_DB_MAX (MDB_IDL_DB_SIZE-1) 65 #define MDB_IDL_UM_MAX (MDB_IDL_UM_SIZE-1) 66 67 #define MDB_IDL_SIZEOF(ids) (((ids)[0]+1) * sizeof(MDB_ID)) 68 #define MDB_IDL_IS_ZERO(ids) ( (ids)[0] == 0 ) 69 #define MDB_IDL_CPY( dst, src ) (memcpy( dst, src, MDB_IDL_SIZEOF( src ) )) 70 #define MDB_IDL_FIRST( ids ) ( (ids)[1] ) 71 #define MDB_IDL_LAST( ids ) ( (ids)[(ids)[0]] ) 72 73 /** Current max length of an #mdb_midl_alloc()ed IDL */ 74 #define MDB_IDL_ALLOCLEN( ids ) ( (ids)[-1] ) 75 76 /** Append ID to IDL. The IDL must be big enough. */ 77 #define mdb_midl_xappend(idl, id) do { \ 78 MDB_ID *xidl = (idl), xlen = ++(xidl[0]); \ 79 xidl[xlen] = (id); \ 80 } while (0) 81 82 /** Search for an ID in an IDL. 83 * @param[in] ids The IDL to search. 84 * @param[in] id The ID to search for. 85 * @return The index of the first ID greater than or equal to \b id. 86 */ 87 unsigned mdb_midl_search( MDB_IDL ids, MDB_ID id ); 88 89 /** Allocate an IDL. 90 * Allocates memory for an IDL of the given size. 91 * @return IDL on success, NULL on failure. 92 */ 93 MDB_IDL mdb_midl_alloc(int num); 94 95 /** Free an IDL. 96 * @param[in] ids The IDL to free. 97 */ 98 void mdb_midl_free(MDB_IDL ids); 99 100 /** Shrink an IDL. 101 * Return the IDL to the default size if it has grown larger. 102 * @param[in,out] idp Address of the IDL to shrink. 103 */ 104 void mdb_midl_shrink(MDB_IDL *idp); 105 106 /** Make room for num additional elements in an IDL. 107 * @param[in,out] idp Address of the IDL. 108 * @param[in] num Number of elements to make room for. 109 * @return 0 on success, ENOMEM on failure. 110 */ 111 int mdb_midl_need(MDB_IDL *idp, unsigned num); 112 113 /** Append an ID onto an IDL. 114 * @param[in,out] idp Address of the IDL to append to. 115 * @param[in] id The ID to append. 116 * @return 0 on success, ENOMEM if the IDL is too large. 117 */ 118 int mdb_midl_append( MDB_IDL *idp, MDB_ID id ); 119 120 /** Append an IDL onto an IDL. 121 * @param[in,out] idp Address of the IDL to append to. 122 * @param[in] app The IDL to append. 123 * @return 0 on success, ENOMEM if the IDL is too large. 124 */ 125 int mdb_midl_append_list( MDB_IDL *idp, MDB_IDL app ); 126 127 /** Append an ID range onto an IDL. 128 * @param[in,out] idp Address of the IDL to append to. 129 * @param[in] id The lowest ID to append. 130 * @param[in] n Number of IDs to append. 131 * @return 0 on success, ENOMEM if the IDL is too large. 132 */ 133 int mdb_midl_append_range( MDB_IDL *idp, MDB_ID id, unsigned n ); 134 135 /** Merge an IDL onto an IDL. The destination IDL must be big enough. 136 * @param[in] idl The IDL to merge into. 137 * @param[in] merge The IDL to merge. 138 */ 139 void mdb_midl_xmerge( MDB_IDL idl, MDB_IDL merge ); 140 141 /** Sort an IDL. 142 * @param[in,out] ids The IDL to sort. 143 */ 144 void mdb_midl_sort( MDB_IDL ids ); 145 146 /** An ID2 is an ID/pointer pair. 147 */ 148 typedef struct MDB_ID2 { 149 MDB_ID mid; /**< The ID */ 150 void *mptr; /**< The pointer */ 151 } MDB_ID2; 152 153 /** An ID2L is an ID2 List, a sorted array of ID2s. 154 * The first element's \b mid member is a count of how many actual 155 * elements are in the array. The \b mptr member of the first element is unused. 156 * The array is sorted in ascending order by \b mid. 157 */ 158 typedef MDB_ID2 *MDB_ID2L; 159 160 /** Search for an ID in an ID2L. 161 * @param[in] ids The ID2L to search. 162 * @param[in] id The ID to search for. 163 * @return The index of the first ID2 whose \b mid member is greater than or equal to \b id. 164 */ 165 unsigned mdb_mid2l_search( MDB_ID2L ids, MDB_ID id ); 166 167 168 /** Insert an ID2 into a ID2L. 169 * @param[in,out] ids The ID2L to insert into. 170 * @param[in] id The ID2 to insert. 171 * @return 0 on success, -1 if the ID was already present in the ID2L. 172 */ 173 int mdb_mid2l_insert( MDB_ID2L ids, MDB_ID2 *id ); 174 175 /** Append an ID2 into a ID2L. 176 * @param[in,out] ids The ID2L to append into. 177 * @param[in] id The ID2 to append. 178 * @return 0 on success, -2 if the ID2L is too big. 179 */ 180 int mdb_mid2l_append( MDB_ID2L ids, MDB_ID2 *id ); 181 182 /** @} */ 183 /** @} */ 184 #ifdef __cplusplus 185 } 186 #endif 187 #endif /* _MDB_MIDL_H_ */ 188
Indexes created Sat Mar 28 00:23:22 UTC 2026