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Diffstat (limited to 'libraries/liblmdb/midl.h')
| -rw-r--r-- | libraries/liblmdb/midl.h | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/libraries/liblmdb/midl.h b/libraries/liblmdb/midl.h new file mode 100644 index 0000000..6bb9cf6 --- /dev/null +++ b/libraries/liblmdb/midl.h @@ -0,0 +1,186 @@ +/** @file midl.h + * @brief LMDB ID List header file. + * + * This file was originally part of back-bdb but has been + * modified for use in libmdb. Most of the macros defined + * in this file are unused, just left over from the original. + * + * This file is only used internally in libmdb and its definitions + * are not exposed publicly. + */ +/* $OpenLDAP$ */ +/* This work is part of OpenLDAP Software <http://www.openldap.org/>. + * + * Copyright 2000-2020 The OpenLDAP Foundation. + * Portions Copyright 2001-2020 Howard Chu, Symas Corp. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted only as authorized by the OpenLDAP + * Public License. + * + * A copy of this license is available in the file LICENSE in the + * top-level directory of the distribution or, alternatively, at + * <http://www.OpenLDAP.org/license.html>. + */ + +#ifndef _MDB_MIDL_H_ +#define _MDB_MIDL_H_ + +#include <stddef.h> + +#ifdef __cplusplus +extern "C" { +#endif + +/** @defgroup internal LMDB Internals + * @{ + */ + +/** @defgroup idls ID List Management + * @{ + */ + /** A generic unsigned ID number. These were entryIDs in back-bdb. + * Preferably it should have the same size as a pointer. + */ +typedef size_t MDB_ID; + + /** An IDL is an ID List, a sorted array of IDs. The first + * element of the array is a counter for how many actual + * IDs are in the list. In the original back-bdb code, IDLs are + * sorted in ascending order. For libmdb IDLs are sorted in + * descending order. + */ +typedef MDB_ID *MDB_IDL; + +/* IDL sizes - likely should be even bigger + * limiting factors: sizeof(ID), thread stack size + */ +#define MDB_IDL_LOGN 16 /* DB_SIZE is 2^16, UM_SIZE is 2^17 */ +#define MDB_IDL_DB_SIZE (1<<MDB_IDL_LOGN) +#define MDB_IDL_UM_SIZE (1<<(MDB_IDL_LOGN+1)) + +#define MDB_IDL_DB_MAX (MDB_IDL_DB_SIZE-1) +#define MDB_IDL_UM_MAX (MDB_IDL_UM_SIZE-1) + +#define MDB_IDL_SIZEOF(ids) (((ids)[0]+1) * sizeof(MDB_ID)) +#define MDB_IDL_IS_ZERO(ids) ( (ids)[0] == 0 ) +#define MDB_IDL_CPY( dst, src ) (memcpy( dst, src, MDB_IDL_SIZEOF( src ) )) +#define MDB_IDL_FIRST( ids ) ( (ids)[1] ) +#define MDB_IDL_LAST( ids ) ( (ids)[(ids)[0]] ) + + /** Current max length of an #mdb_midl_alloc()ed IDL */ +#define MDB_IDL_ALLOCLEN( ids ) ( (ids)[-1] ) + + /** Append ID to IDL. The IDL must be big enough. */ +#define mdb_midl_xappend(idl, id) do { \ + MDB_ID *xidl = (idl), xlen = ++(xidl[0]); \ + xidl[xlen] = (id); \ + } while (0) + + /** Search for an ID in an IDL. + * @param[in] ids The IDL to search. + * @param[in] id The ID to search for. + * @return The index of the first ID greater than or equal to \b id. + */ +unsigned mdb_midl_search( MDB_IDL ids, MDB_ID id ); + + /** Allocate an IDL. + * Allocates memory for an IDL of the given size. + * @return IDL on success, NULL on failure. + */ +MDB_IDL mdb_midl_alloc(int num); + + /** Free an IDL. + * @param[in] ids The IDL to free. + */ +void mdb_midl_free(MDB_IDL ids); + + /** Shrink an IDL. + * Return the IDL to the default size if it has grown larger. + * @param[in,out] idp Address of the IDL to shrink. + */ +void mdb_midl_shrink(MDB_IDL *idp); + + /** Make room for num additional elements in an IDL. + * @param[in,out] idp Address of the IDL. + * @param[in] num Number of elements to make room for. + * @return 0 on success, ENOMEM on failure. + */ +int mdb_midl_need(MDB_IDL *idp, unsigned num); + + /** Append an ID onto an IDL. + * @param[in,out] idp Address of the IDL to append to. + * @param[in] id The ID to append. + * @return 0 on success, ENOMEM if the IDL is too large. + */ +int mdb_midl_append( MDB_IDL *idp, MDB_ID id ); + + /** Append an IDL onto an IDL. + * @param[in,out] idp Address of the IDL to append to. + * @param[in] app The IDL to append. + * @return 0 on success, ENOMEM if the IDL is too large. + */ +int mdb_midl_append_list( MDB_IDL *idp, MDB_IDL app ); + + /** Append an ID range onto an IDL. + * @param[in,out] idp Address of the IDL to append to. + * @param[in] id The lowest ID to append. + * @param[in] n Number of IDs to append. + * @return 0 on success, ENOMEM if the IDL is too large. + */ +int mdb_midl_append_range( MDB_IDL *idp, MDB_ID id, unsigned n ); + + /** Merge an IDL onto an IDL. The destination IDL must be big enough. + * @param[in] idl The IDL to merge into. + * @param[in] merge The IDL to merge. + */ +void mdb_midl_xmerge( MDB_IDL idl, MDB_IDL merge ); + + /** Sort an IDL. + * @param[in,out] ids The IDL to sort. + */ +void mdb_midl_sort( MDB_IDL ids ); + + /** An ID2 is an ID/pointer pair. + */ +typedef struct MDB_ID2 { + MDB_ID mid; /**< The ID */ + void *mptr; /**< The pointer */ +} MDB_ID2; + + /** An ID2L is an ID2 List, a sorted array of ID2s. + * The first element's \b mid member is a count of how many actual + * elements are in the array. The \b mptr member of the first element is unused. + * The array is sorted in ascending order by \b mid. + */ +typedef MDB_ID2 *MDB_ID2L; + + /** Search for an ID in an ID2L. + * @param[in] ids The ID2L to search. + * @param[in] id The ID to search for. + * @return The index of the first ID2 whose \b mid member is greater than or equal to \b id. + */ +unsigned mdb_mid2l_search( MDB_ID2L ids, MDB_ID id ); + + + /** Insert an ID2 into a ID2L. + * @param[in,out] ids The ID2L to insert into. + * @param[in] id The ID2 to insert. + * @return 0 on success, -1 if the ID was already present in the ID2L. + */ +int mdb_mid2l_insert( MDB_ID2L ids, MDB_ID2 *id ); + + /** Append an ID2 into a ID2L. + * @param[in,out] ids The ID2L to append into. + * @param[in] id The ID2 to append. + * @return 0 on success, -2 if the ID2L is too big. + */ +int mdb_mid2l_append( MDB_ID2L ids, MDB_ID2 *id ); + +/** @} */ +/** @} */ +#ifdef __cplusplus +} +#endif +#endif /* _MDB_MIDL_H_ */ |