1/* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements.  See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License.  You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef APR_RMM_H
18#define APR_RMM_H
19/**
20 * @file apr_rmm.h
21 * @brief APR-UTIL Relocatable Memory Management Routines
22 */
23/**
24 * @defgroup APR_Util_RMM Relocatable Memory Management Routines
25 * @ingroup APR_Util
26 * @{
27 */
28
29#include "apr.h"
30#include "apr_pools.h"
31#include "apr_errno.h"
32#include "apu.h"
33#include "apr_anylock.h"
34
35#ifdef __cplusplus
36extern "C" {
37#endif /* __cplusplus */
38
39/** Structure to access Relocatable, Managed Memory */
40typedef struct apr_rmm_t apr_rmm_t;
41
42/** Fundamental allocation unit, within a specific apr_rmm_t */
43typedef apr_size_t   apr_rmm_off_t;
44
45/**
46 * Initialize a relocatable memory block to be managed by the apr_rmm API.
47 * @param rmm The relocatable memory block
48 * @param lock An apr_anylock_t of the appropriate type of lock, or NULL
49 *             if no locking is required.
50 * @param membuf The block of relocatable memory to be managed
51 * @param memsize The size of relocatable memory block to be managed
52 * @param cont The pool to use for local storage and management
53 * @remark Both @param membuf and @param memsize must be aligned
54 * (for instance using APR_ALIGN_DEFAULT).
55 */
56APU_DECLARE(apr_status_t) apr_rmm_init(apr_rmm_t **rmm, apr_anylock_t *lock,
57                                       void *membuf, apr_size_t memsize,
58                                       apr_pool_t *cont);
59
60/**
61 * Destroy a managed memory block.
62 * @param rmm The relocatable memory block to destroy
63 */
64APU_DECLARE(apr_status_t) apr_rmm_destroy(apr_rmm_t *rmm);
65
66/**
67 * Attach to a relocatable memory block already managed by the apr_rmm API.
68 * @param rmm The relocatable memory block
69 * @param lock An apr_anylock_t of the appropriate type of lock
70 * @param membuf The block of relocatable memory already under management
71 * @param cont The pool to use for local storage and management
72 */
73APU_DECLARE(apr_status_t) apr_rmm_attach(apr_rmm_t **rmm, apr_anylock_t *lock,
74                                         void *membuf, apr_pool_t *cont);
75
76/**
77 * Detach from the managed block of memory.
78 * @param rmm The relocatable memory block to detach from
79 */
80APU_DECLARE(apr_status_t) apr_rmm_detach(apr_rmm_t *rmm);
81
82/**
83 * Allocate memory from the block of relocatable memory.
84 * @param rmm The relocatable memory block
85 * @param reqsize How much memory to allocate
86 */
87APU_DECLARE(apr_rmm_off_t) apr_rmm_malloc(apr_rmm_t *rmm, apr_size_t reqsize);
88
89/**
90 * Realloc memory from the block of relocatable memory.
91 * @param rmm The relocatable memory block
92 * @param entity The memory allocation to realloc
93 * @param reqsize The new size
94 */
95APU_DECLARE(apr_rmm_off_t) apr_rmm_realloc(apr_rmm_t *rmm, void *entity, apr_size_t reqsize);
96
97/**
98 * Allocate memory from the block of relocatable memory and initialize it to zero.
99 * @param rmm The relocatable memory block
100 * @param reqsize How much memory to allocate
101 */
102APU_DECLARE(apr_rmm_off_t) apr_rmm_calloc(apr_rmm_t *rmm, apr_size_t reqsize);
103
104/**
105 * Free allocation returned by apr_rmm_malloc or apr_rmm_calloc.
106 * @param rmm The relocatable memory block
107 * @param entity The memory allocation to free
108 */
109APU_DECLARE(apr_status_t) apr_rmm_free(apr_rmm_t *rmm, apr_rmm_off_t entity);
110
111/**
112 * Retrieve the physical address of a relocatable allocation of memory
113 * @param rmm The relocatable memory block
114 * @param entity The memory allocation to free
115 * @return address The address, aligned with APR_ALIGN_DEFAULT.
116 */
117APU_DECLARE(void *) apr_rmm_addr_get(apr_rmm_t *rmm, apr_rmm_off_t entity);
118
119/**
120 * Compute the offset of a relocatable allocation of memory
121 * @param rmm The relocatable memory block
122 * @param entity The physical address to convert to an offset
123 */
124APU_DECLARE(apr_rmm_off_t) apr_rmm_offset_get(apr_rmm_t *rmm, void *entity);
125
126/**
127 * Compute the required overallocation of memory needed to fit n allocs
128 * @param n The number of alloc/calloc regions desired
129 */
130APU_DECLARE(apr_size_t) apr_rmm_overhead_get(int n);
131
132#ifdef __cplusplus
133}
134#endif
135/** @} */
136#endif  /* ! APR_RMM_H */
137
138