aboutsummaryrefslogtreecommitdiff
path: root/external/db_drivers/liblmdb32/midl.h
blob: 1e5fee797f634c324516825f4f6f22c2fcf9d43d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
/**	@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 2000-2015 The OpenLDAP Foundation.
 * 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
 */
#ifdef VL32
#define	MDB_IDL_LOGN	10	/* DB_SIZE is 2^10, UM_SIZE is 2^11 */
#else
 #define	MDB_IDL_LOGN	16	/* DB_SIZE is 2^16, UM_SIZE is 2^17 */
#endif
#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.
	 * @return	0 on no change, non-zero if shrunk.
	 */
int 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_ */