-
Notifications
You must be signed in to change notification settings - Fork 0
/
bytes-allocator.c
378 lines (337 loc) · 14.9 KB
/
bytes-allocator.c
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
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
/**
* JCUnit - a very simple unit testing framework for C
*
* Copyright (C) 2021-2022 Denis Korchagin <denis.korchagin.1995@gmail.com>
*
* This file is part of JCUnit
*
* For the full license information, please view the LICENSE
* file that was distributed with this source code.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation of version 2
* of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <stdbool.h>
#include <assert.h>
#include "headers/object-allocator.h"
#include "headers/errors.h"
#define MAX_BYTES_POOL_SIZE (64 * 1024)
#define BYTES_CHUNK_HEADER_SIGNATURE (0x8641ca7f)
#define BYTES_CHUNK_HEADER_SIZE (sizeof(struct bytes_chunk_header))
#define WORD_SIZE (sizeof(void *))
#define bytes_chunk_data(bs) ((void *)(bs) + BYTES_CHUNK_HEADER_SIZE)
#define bytes_chunk_offset(bs) ((unsigned int)((bs)->size + (bs)->alignment + BYTES_CHUNK_HEADER_SIZE))
#define bytes_chunk_get_chunk(pool, offset) ((struct bytes_chunk_header *)((void *)(pool + offset)))
#define bytes_chunk_offset_from_pool(pointer, pool) ((unsigned int)((void *)(pointer) - (void *)(pool)))
#define bytes_chunks_foreach(chunk_name, body) \
do \
{ \
unsigned int ___cursor; \
struct bytes_chunk_header * chunk_name = NULL; \
for (___cursor = 0; ___cursor < bytes_pool_pos; ___cursor += bytes_chunk_offset(chunk_name)) { \
chunk_name = (struct bytes_chunk_header *)((void *)bytes_pool + ___cursor); \
if (chunk_name->signature != BYTES_CHUNK_HEADER_SIGNATURE) \
break; \
body \
} \
} \
while(0)
struct bytes_chunk_header
{
unsigned int signature;
unsigned int alignment:31, is_busy:1;
unsigned int size;
};
struct defragmentation_info
{
struct bytes_chunk_header * first_free_chunk_pair;
struct bytes_chunk_header * first_free_chunk_between_busy_chunks;
};
static unsigned char bytes_pool[MAX_BYTES_POOL_SIZE] = {0};
static unsigned int bytes_pool_pos = 0;
static unsigned int allocated_bytes = 0;
static unsigned int freed_bytes = 0;
static void * bytes_pool_low_bound = (void *)bytes_pool + BYTES_CHUNK_HEADER_SIZE;
static void * bytes_pool_high_bound = (void *)bytes_pool + MAX_BYTES_POOL_SIZE - BYTES_CHUNK_HEADER_SIZE;
static struct bytes_chunk_header * try_to_allocate_new_chunk(unsigned int len);
static struct bytes_chunk_header * find_first_free_chunk_pair(unsigned int start_offset);
/* static struct bytes_chunk_header * find_latest_free_chunk(unsigned int start_offset); */
static struct bytes_chunk_header * bytes_chunk_merge(struct bytes_chunk_header * onto, struct bytes_chunk_header * src);
static struct bytes_chunk_header * find_free_chunk_of_size(unsigned int len);
static bool needs_defragmentation(struct defragmentation_info * defragmentation_info);
static void do_defragmentation(struct defragmentation_info * defragmentation_info);
void * alloc_bytes(unsigned int len)
{
struct defragmentation_info defragmentation_info = {NULL, NULL};
if (needs_defragmentation(&defragmentation_info)) {
do_defragmentation(&defragmentation_info);
}
struct bytes_chunk_header * chunk = find_free_chunk_of_size(len);
if (chunk == NULL) {
chunk = try_to_allocate_new_chunk(len);
}
chunk->is_busy = 1;
allocated_bytes += chunk->size;
return bytes_chunk_data(chunk);
}
void free_bytes(void * mem)
{
if (mem < bytes_pool_low_bound || mem > bytes_pool_high_bound) {
jcunit_fatal_error("Allocator bytes: try to free memory which out of allocator's bound!\n");
}
struct bytes_chunk_header * chunk = (struct bytes_chunk_header *)(mem - BYTES_CHUNK_HEADER_SIZE);
if (chunk->signature != BYTES_CHUNK_HEADER_SIGNATURE)
jcunit_fatal_error("Allocator bytes: try to free not managed memory!\n");
chunk->is_busy = 0;
freed_bytes += chunk->size;
}
void show_bytes_allocator_stats(FILE * output, bool show_leak_only)
{
if (show_leak_only && !(allocated_bytes > freed_bytes)) {
return;
}
unsigned int max_bytes_pool_size = MAX_BYTES_POOL_SIZE;
const char * allocator_status = "OK";
if (allocated_bytes < freed_bytes) {
allocator_status = "ALLOCATION MISMATCH";
} else if (allocated_bytes > freed_bytes) {
allocator_status = "LEAK";
}
fprintf(
output,
"Allocator: bytes, total: %u, pool_usage: %u, allocated: %u, freed: %u [%s]\n",
max_bytes_pool_size,
bytes_pool_pos,
allocated_bytes,
freed_bytes,
allocator_status
);
unsigned int chunk_count = 0;
unsigned int mem_size_in_chunks = 0;
unsigned int mem_for_align_chunks = 0;
bytes_chunks_foreach(chunk, {
mem_size_in_chunks += chunk->size;
mem_for_align_chunks += chunk->alignment;
++chunk_count;
});
unsigned int chunks_occupied_mem = chunk_count * (unsigned int)BYTES_CHUNK_HEADER_SIZE;
fprintf(
output,
"\tchunk descriptor size: %lu, chunk_count: %u, chunks occupied mem: %u, "
"mem size in chunks: %u, mem for align chunks: %u\n",
BYTES_CHUNK_HEADER_SIZE,
chunk_count,
chunks_occupied_mem,
mem_size_in_chunks,
mem_for_align_chunks
);
fprintf(output, "\tChunk Memory Map: [");
unsigned int max_chunk_size = 0;
unsigned int min_chunk_size = UINT32_MAX;
unsigned int chunk_size_sum = 0;
bytes_chunks_foreach(chunk, {
fprintf(output, "%c", chunk->is_busy ? 'C' : 'F');
if (chunk->size < min_chunk_size) {
min_chunk_size = chunk->size;
}
if (chunk->size > max_chunk_size) {
max_chunk_size = chunk->size;
}
chunk_size_sum += chunk->size;
});
fprintf(output, "]\n");
fprintf(output, "\tMin Chunk Size: %u\n", min_chunk_size);
fprintf(output, "\tMax Chunk Size: %u\n", max_chunk_size);
fprintf(output, "\tAverage Chunk Size: %u\n", chunk_size_sum / chunk_count);
fprintf(output, "\tChunks:\n");
unsigned int chunk_index = 0;
bytes_chunks_foreach(chunk, {
++chunk_index;
fprintf(
output,
"\t\t%u) %c size: %u, alignment: %u (%s)\n",
chunk_index,
chunk->is_busy ? 'C' : 'F',
chunk->size,
chunk->alignment,
(BYTES_CHUNK_HEADER_SIZE + chunk->size + chunk->alignment) % WORD_SIZE == 0 ? "aligned" : "not aligned"
);
});
fflush(output);
}
struct bytes_chunk_header * bytes_chunk_merge(struct bytes_chunk_header * onto, struct bytes_chunk_header * src)
{
assert(onto != NULL);
assert(src != NULL);
unsigned int new_chunk_size = onto->size + onto->alignment + bytes_chunk_offset(src);
/* destroy chunk entry */
src->signature = 0;
onto->size = new_chunk_size;
onto->alignment = 0;
if ((onto->size + BYTES_CHUNK_HEADER_SIZE) % WORD_SIZE != 0) {
jcunit_fatal_error("One of chunks were not aligned!\n");
}
return onto;
}
/* TODO: it needs to review */
struct bytes_chunk_header * find_latest_free_chunk(unsigned int start_offset)
{
unsigned int offset = start_offset;
struct bytes_chunk_header * last_chunk = NULL;
for (;;) {
if (offset >= bytes_pool_pos)
break;
struct bytes_chunk_header * chunk = bytes_chunk_get_chunk(bytes_pool, offset);
if (chunk->signature != BYTES_CHUNK_HEADER_SIGNATURE)
break;
last_chunk = chunk;
offset += bytes_chunk_offset(chunk);
}
if (last_chunk != NULL && last_chunk->is_busy == 0) {
return last_chunk;
}
return NULL;
}
struct bytes_chunk_header * find_first_free_chunk_between_busy_chunks(unsigned int start_offset)
{
unsigned int offset = start_offset;
for (;;) {
if (offset >= bytes_pool_pos)
break;
struct bytes_chunk_header * chunk = bytes_chunk_get_chunk(bytes_pool, offset);
if (chunk->signature != BYTES_CHUNK_HEADER_SIGNATURE)
break;
unsigned int next_chunk_offset = offset + bytes_chunk_offset(chunk);
struct bytes_chunk_header * next_chunk = next_chunk_offset >= bytes_pool_pos
? NULL
: bytes_chunk_get_chunk(bytes_pool, next_chunk_offset);
if (next_chunk == NULL || next_chunk->signature != BYTES_CHUNK_HEADER_SIGNATURE)
break;
unsigned int next_next_chunk_offset = next_chunk_offset + bytes_chunk_offset(next_chunk);
struct bytes_chunk_header * next_next_chunk = next_next_chunk_offset >= bytes_pool_pos
? NULL
: bytes_chunk_get_chunk(bytes_pool, next_next_chunk_offset);
if (next_next_chunk == NULL || next_next_chunk->signature != BYTES_CHUNK_HEADER_SIGNATURE)
break;
if (chunk->is_busy == 1 && next_chunk->is_busy == 0 && next_next_chunk->is_busy == 1) {
return chunk;
}
offset = next_next_chunk_offset + bytes_chunk_offset(next_next_chunk);
}
return NULL;
}
struct bytes_chunk_header * find_first_free_chunk_pair(unsigned int start_offset)
{
unsigned int offset = start_offset;
for (;;) {
if (offset >= bytes_pool_pos)
break;
struct bytes_chunk_header * chunk = bytes_chunk_get_chunk(bytes_pool, offset);
if (chunk->signature != BYTES_CHUNK_HEADER_SIGNATURE)
break;
unsigned int next_chunk_offset = offset + bytes_chunk_offset(chunk);
struct bytes_chunk_header * next_chunk = next_chunk_offset >= bytes_pool_pos
? NULL
: bytes_chunk_get_chunk(bytes_pool, next_chunk_offset);
if (next_chunk == NULL || next_chunk->signature != BYTES_CHUNK_HEADER_SIGNATURE)
break;
if (chunk->is_busy == 0 && next_chunk->is_busy == 0) {
return chunk;
}
offset = next_chunk_offset + bytes_chunk_offset(next_chunk);
}
return NULL;
}
struct bytes_chunk_header * find_free_chunk_of_size(unsigned int len)
{
bytes_chunks_foreach(chunk, {
if (chunk->is_busy == 1)
continue;
if (chunk->size >= len)
return chunk;
});
return NULL;
}
struct bytes_chunk_header * try_to_allocate_new_chunk(unsigned int len)
{
unsigned int full_chunk_size = len + BYTES_CHUNK_HEADER_SIZE;
unsigned int alignment = full_chunk_size % WORD_SIZE;
if (alignment != 0)
alignment = WORD_SIZE - alignment;
full_chunk_size += alignment;
if (bytes_pool_pos + full_chunk_size >= MAX_BYTES_POOL_SIZE) {
jcunit_fatal_error("Allocator bytes: out of memory!");
}
struct bytes_chunk_header * chunk = bytes_chunk_get_chunk(bytes_pool, bytes_pool_pos);
chunk->signature = BYTES_CHUNK_HEADER_SIGNATURE;
chunk->alignment = alignment;
chunk->size = len;
bytes_pool_pos += full_chunk_size;
return chunk;
}
bool needs_defragmentation(struct defragmentation_info * defragmentation_info)
{
defragmentation_info->first_free_chunk_pair = find_first_free_chunk_pair(0);
defragmentation_info->first_free_chunk_between_busy_chunks = find_first_free_chunk_between_busy_chunks(0);
return defragmentation_info->first_free_chunk_pair != NULL
|| defragmentation_info->first_free_chunk_between_busy_chunks != NULL;
}
void do_defragmentation(struct defragmentation_info * defragmentation_info)
{
if (defragmentation_info->first_free_chunk_pair != NULL) {
unsigned int offset;
struct bytes_chunk_header * first_chunk, * second_chunk;
for (;;) {
first_chunk = defragmentation_info->first_free_chunk_pair;
offset = bytes_chunk_offset_from_pool(defragmentation_info->first_free_chunk_pair, bytes_pool);
offset += bytes_chunk_offset(first_chunk);
second_chunk = bytes_chunk_get_chunk(bytes_pool, offset);
if (first_chunk->is_busy == 1 || second_chunk->is_busy == 1) {
jcunit_fatal_error("Cannot merge any busy chunks!");
}
bytes_chunk_merge(first_chunk, second_chunk);
offset += bytes_chunk_offset(second_chunk);
defragmentation_info->first_free_chunk_pair = find_first_free_chunk_pair(offset);
if (defragmentation_info->first_free_chunk_pair == NULL) {
break;
}
}
}
if (defragmentation_info->first_free_chunk_between_busy_chunks != NULL) {
unsigned int offset;
struct bytes_chunk_header * first_chunk, * second_chunk;
for (;;) {
first_chunk = defragmentation_info->first_free_chunk_between_busy_chunks;
offset = bytes_chunk_offset_from_pool(
defragmentation_info->first_free_chunk_between_busy_chunks,
bytes_pool
);
offset += bytes_chunk_offset(first_chunk);
second_chunk = bytes_chunk_get_chunk(bytes_pool, offset);
if (second_chunk->is_busy != 0) {
jcunit_fatal_error("Cannot merge a chunk with another busy chunk!");
}
allocated_bytes -= first_chunk->size;
bytes_chunk_merge(first_chunk, second_chunk);
allocated_bytes += first_chunk->size;
offset += bytes_chunk_offset(second_chunk);
defragmentation_info->first_free_chunk_between_busy_chunks = find_first_free_chunk_between_busy_chunks(
offset
);
if (defragmentation_info->first_free_chunk_between_busy_chunks == NULL) {
break;
}
}
}
}