1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 *
4 * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include "cx/basic_mempool.h"
30 #include "cx/utils.h"
31 #include <string.h>
32
33 #define of_chk_(n) if (SIZE_MAX - sizeof(cx_destructor_func) < (n)) return NULL
34
35 /** Internal structure for denoting pooled memory. */
36 typedef struct {
37 /** The destructor. */
38 cx_destructor_func destructor;
39 /**
40 * Access to the first byte of the polled memory.
41 */
42 char c;
43 } cx_basic_mempool_memory;
44
45 static int cx_basic_mempool_chcap(
46 struct cx_basic_mempool_s *pool,
47 size_t newcap
48 ) {
49 if (newcap < pool->ndata) {
50 return 1;
51 }
52
53 size_t newcapsz;
54 if (cx_szmul(newcap, sizeof(void *), &newcapsz)) {
55 return 1;
56 }
57
58 void **data = realloc(pool->data, newcapsz);
59 if (data) {
60 pool->data = data;
61 pool->size = newcap;
62 return 0;
63 } else {
64 return 1;
65 }
66 }
67
68 void *cx_malloc_basic_mempool(
69 void *data,
70 size_t n
71 ) {
72 of_chk_(n);
73 struct cx_basic_mempool_s *pool = data;
74
75 if (pool->ndata >= pool->size) {
76 size_t newcap = pool->size * 2;
77 if (newcap < pool->size || cx_basic_mempool_chcap(pool, newcap)) {
78 return NULL;
79 }
80 }
81
82 cx_basic_mempool_memory *mem = malloc(sizeof(cx_destructor_func) + n);
83 if (mem == NULL) {
84 return NULL;
85 }
86
87 mem->destructor = NULL;
88 pool->data[pool->ndata] = mem;
89 pool->ndata++;
90
91 return &(mem->c);
92 }
93
94 void *cx_calloc_basic_mempool(
95 void *data,
96 size_t nelem,
97 size_t elsize
98 ) {
99 size_t msz;
100 if (cx_szmul(nelem, elsize, &msz)) {
101 return NULL;
102 }
103 void *ptr = cx_malloc_basic_mempool(data, msz);
104 if (ptr == NULL) {
105 return NULL;
106 }
107 memset(ptr, 0, nelem * elsize);
108 return ptr;
109 }
110
111 void *cx_realloc_basic_mempool(
112 void *data,
113 void *ptr,
114 size_t n
115 ) {
116 of_chk_(n);
117 struct cx_basic_mempool_s *pool = data;
118
119 char *mem = ((char *) ptr) - sizeof(cx_destructor_func);
120 char *newm = (char *) realloc(mem, n + sizeof(cx_destructor_func));
121 if (newm == NULL) {
122 return NULL;
123 }
124 if (mem != newm) {
125 cx_for_n(i, pool->ndata) {
126 if (pool->data[i] == mem) {
127 pool->data[i] = newm;
128 return newm + sizeof(cx_destructor_func);
129 }
130 }
131 abort();
132 } else {
133 return newm + sizeof(cx_destructor_func);
134 }
135 }
136
137 void cx_free_basic_mempool(
138 void *data,
139 void *ptr
140 ) {
141 struct cx_basic_mempool_s *pool = data;
142
143 cx_basic_mempool_memory *mem = (cx_basic_mempool_memory *)
144 ((char *) ptr - sizeof(cx_destructor_func));
145 cx_for_n(i, pool->ndata) {
146 if (mem == pool->data[i]) {
147 if (mem->destructor != NULL) {
148 mem->destructor(&(mem->c));
149 }
150 free(mem);
151 size_t last_index = pool->ndata - 1;
152 if (i != last_index) {
153 pool->data[i] = pool->data[last_index];
154 pool->data[last_index] = NULL;
155 }
156 pool->ndata--;
157 return;
158 }
159 }
160 abort();
161 }
162
163 void cx_basic_mempool_destroy(CxMempool *p) {
164 struct cx_basic_mempool_s *pool = (struct cx_basic_mempool_s *) p;
165 cx_basic_mempool_memory *mem;
166 cx_for_n(i, pool->ndata) {
167 mem = (cx_basic_mempool_memory *) pool->data[i];
168 if (mem) {
169 if (mem->destructor) {
170 mem->destructor(&(mem->c));
171 }
172 free(mem);
173 }
174 }
175 free(pool->data);
176 free((void *) p->allocator);
177 free(pool);
178 }
179
180 void cx_basic_mempool_set_destr(
181 __attribute__((__unused__)) CxMempool *pool,
182 void *ptr,
183 cx_destructor_func func
184 ) {
185 *(cx_destructor_func *) ((char *) ptr - sizeof(cx_destructor_func)) = func;
186 }
187
188 static cx_allocator_class cx_basic_mempool_allocator_class = {
189 cx_malloc_basic_mempool,
190 cx_realloc_basic_mempool,
191 cx_calloc_basic_mempool,
192 cx_free_basic_mempool
193 };
194
195 static cx_mempool_class cx_basic_mempool_class = {
196 cx_basic_mempool_destroy,
197 cx_basic_mempool_set_destr,
198 };
199
200 CxMempool *cxBasicMempoolCreate(size_t capacity) {
201 size_t poolsize;
202 if (cx_szmul(capacity, sizeof(void *), &poolsize)) {
203 return NULL;
204 }
205
206 struct cx_basic_mempool_s *pool =
207 malloc(sizeof(struct cx_basic_mempool_s));
208 if (pool == NULL) {
209 return NULL;
210 }
211
212
213 CxAllocator *provided_allocator = malloc(sizeof(CxAllocator));
214 if (!provided_allocator) {
215 free(pool);
216 return NULL;
217 }
218 provided_allocator->cl = &cx_basic_mempool_allocator_class;
219 provided_allocator->data = pool;
220
221 pool->base.cl = &cx_basic_mempool_class;
222 pool->base.allocator = provided_allocator;
223
224 pool->data = malloc(poolsize);
225 if (pool->data == NULL) {
226 free(provided_allocator);
227 free(pool);
228 return NULL;
229 }
230
231 pool->ndata = 0;
232 pool->size = capacity;
233
234 return (CxMempool *) pool;
235 }
236