1 | /* |
2 | * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. |
3 | * |
4 | * Licensed under the Apache License, Version 2.0 (the "License"). |
5 | * You may not use this file except in compliance with the License. |
6 | * A copy of the License is located at |
7 | * |
8 | * http://aws.amazon.com/apache2.0 |
9 | * |
10 | * or in the "license" file accompanying this file. This file is distributed |
11 | * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either |
12 | * express or implied. See the License for the specific language governing |
13 | * permissions and limitations under the License. |
14 | */ |
15 | |
16 | #include <aws/common/assert.h> |
17 | #include <aws/common/common.h> |
18 | #include <aws/common/logging.h> |
19 | #include <aws/common/math.h> |
20 | |
21 | #include <stdarg.h> |
22 | #include <stdlib.h> |
23 | |
24 | #ifdef _WIN32 |
25 | # include <Windows.h> |
26 | #endif |
27 | |
28 | #ifdef __MACH__ |
29 | # include <CoreFoundation/CoreFoundation.h> |
30 | #endif |
31 | |
32 | /* turn off unused named parameter warning on msvc.*/ |
33 | #ifdef _MSC_VER |
34 | # pragma warning(push) |
35 | # pragma warning(disable : 4100) |
36 | #endif |
37 | |
38 | bool aws_allocator_is_valid(const struct aws_allocator *alloc) { |
39 | /* An allocator must define mem_acquire and mem_release. All other fields are optional */ |
40 | return alloc && AWS_OBJECT_PTR_IS_READABLE(alloc) && alloc->mem_acquire && alloc->mem_release; |
41 | } |
42 | |
43 | static void *s_default_malloc(struct aws_allocator *allocator, size_t size) { |
44 | (void)allocator; |
45 | return malloc(size); |
46 | } |
47 | |
48 | static void s_default_free(struct aws_allocator *allocator, void *ptr) { |
49 | (void)allocator; |
50 | free(ptr); |
51 | } |
52 | |
53 | static void *s_default_realloc(struct aws_allocator *allocator, void *ptr, size_t oldsize, size_t newsize) { |
54 | (void)allocator; |
55 | (void)oldsize; |
56 | return realloc(ptr, newsize); |
57 | } |
58 | |
59 | static void *s_default_calloc(struct aws_allocator *allocator, size_t num, size_t size) { |
60 | (void)allocator; |
61 | return calloc(num, size); |
62 | } |
63 | |
64 | static struct aws_allocator default_allocator = { |
65 | .mem_acquire = s_default_malloc, |
66 | .mem_release = s_default_free, |
67 | .mem_realloc = s_default_realloc, |
68 | .mem_calloc = s_default_calloc, |
69 | }; |
70 | |
71 | struct aws_allocator *aws_default_allocator(void) { |
72 | return &default_allocator; |
73 | } |
74 | |
75 | void *aws_mem_acquire(struct aws_allocator *allocator, size_t size) { |
76 | AWS_FATAL_PRECONDITION(allocator != NULL); |
77 | AWS_FATAL_PRECONDITION(allocator->mem_acquire != NULL); |
78 | /* Protect against https://wiki.sei.cmu.edu/confluence/display/c/MEM04-C.+Beware+of+zero-length+allocations */ |
79 | AWS_FATAL_PRECONDITION(size != 0); |
80 | |
81 | void *mem = allocator->mem_acquire(allocator, size); |
82 | if (!mem) { |
83 | aws_raise_error(AWS_ERROR_OOM); |
84 | } |
85 | return mem; |
86 | } |
87 | |
88 | void *aws_mem_calloc(struct aws_allocator *allocator, size_t num, size_t size) { |
89 | AWS_FATAL_PRECONDITION(allocator != NULL); |
90 | AWS_FATAL_PRECONDITION(allocator->mem_calloc || allocator->mem_acquire); |
91 | /* Protect against https://wiki.sei.cmu.edu/confluence/display/c/MEM04-C.+Beware+of+zero-length+allocations */ |
92 | AWS_FATAL_PRECONDITION(num != 0 && size != 0); |
93 | |
94 | /* Defensive check: never use calloc with size * num that would overflow |
95 | * https://wiki.sei.cmu.edu/confluence/display/c/MEM07-C.+Ensure+that+the+arguments+to+calloc%28%29%2C+when+multiplied%2C+do+not+wrap |
96 | */ |
97 | size_t required_bytes; |
98 | if (aws_mul_size_checked(num, size, &required_bytes)) { |
99 | return NULL; |
100 | } |
101 | |
102 | /* If there is a defined calloc, use it */ |
103 | if (allocator->mem_calloc) { |
104 | void *mem = allocator->mem_calloc(allocator, num, size); |
105 | if (!mem) { |
106 | aws_raise_error(AWS_ERROR_OOM); |
107 | } |
108 | return mem; |
109 | } |
110 | |
111 | /* Otherwise, emulate calloc */ |
112 | void *mem = allocator->mem_acquire(allocator, required_bytes); |
113 | if (!mem) { |
114 | aws_raise_error(AWS_ERROR_OOM); |
115 | return NULL; |
116 | } |
117 | memset(mem, 0, required_bytes); |
118 | AWS_POSTCONDITION(mem != NULL); |
119 | return mem; |
120 | } |
121 | |
122 | #define AWS_ALIGN_ROUND_UP(value, alignment) (((value) + ((alignment)-1)) & ~((alignment)-1)) |
123 | |
124 | void *aws_mem_acquire_many(struct aws_allocator *allocator, size_t count, ...) { |
125 | |
126 | enum { S_ALIGNMENT = sizeof(intmax_t) }; |
127 | |
128 | va_list args_size; |
129 | va_start(args_size, count); |
130 | va_list args_allocs; |
131 | va_copy(args_allocs, args_size); |
132 | |
133 | size_t total_size = 0; |
134 | for (size_t i = 0; i < count; ++i) { |
135 | |
136 | /* Ignore the pointer argument for now */ |
137 | va_arg(args_size, void **); |
138 | |
139 | size_t alloc_size = va_arg(args_size, size_t); |
140 | total_size += AWS_ALIGN_ROUND_UP(alloc_size, S_ALIGNMENT); |
141 | } |
142 | va_end(args_size); |
143 | |
144 | void *allocation = NULL; |
145 | |
146 | if (total_size > 0) { |
147 | |
148 | allocation = aws_mem_acquire(allocator, total_size); |
149 | if (!allocation) { |
150 | aws_raise_error(AWS_ERROR_OOM); |
151 | goto cleanup; |
152 | } |
153 | |
154 | uint8_t *current_ptr = allocation; |
155 | |
156 | for (size_t i = 0; i < count; ++i) { |
157 | |
158 | void **out_ptr = va_arg(args_allocs, void **); |
159 | |
160 | size_t alloc_size = va_arg(args_allocs, size_t); |
161 | alloc_size = AWS_ALIGN_ROUND_UP(alloc_size, S_ALIGNMENT); |
162 | |
163 | *out_ptr = current_ptr; |
164 | current_ptr += alloc_size; |
165 | } |
166 | } |
167 | |
168 | cleanup: |
169 | va_end(args_allocs); |
170 | return allocation; |
171 | } |
172 | |
173 | #undef AWS_ALIGN_ROUND_UP |
174 | |
175 | void aws_mem_release(struct aws_allocator *allocator, void *ptr) { |
176 | AWS_FATAL_PRECONDITION(allocator != NULL); |
177 | AWS_FATAL_PRECONDITION(allocator->mem_release != NULL); |
178 | |
179 | if (ptr != NULL) { |
180 | allocator->mem_release(allocator, ptr); |
181 | } |
182 | } |
183 | |
184 | int aws_mem_realloc(struct aws_allocator *allocator, void **ptr, size_t oldsize, size_t newsize) { |
185 | AWS_FATAL_PRECONDITION(allocator != NULL); |
186 | AWS_FATAL_PRECONDITION(allocator->mem_realloc || allocator->mem_acquire); |
187 | AWS_FATAL_PRECONDITION(allocator->mem_release); |
188 | |
189 | /* Protect against https://wiki.sei.cmu.edu/confluence/display/c/MEM04-C.+Beware+of+zero-length+allocations */ |
190 | if (newsize == 0) { |
191 | aws_mem_release(allocator, *ptr); |
192 | *ptr = NULL; |
193 | return AWS_OP_SUCCESS; |
194 | } |
195 | |
196 | if (allocator->mem_realloc) { |
197 | void *newptr = allocator->mem_realloc(allocator, *ptr, oldsize, newsize); |
198 | if (!newptr) { |
199 | return aws_raise_error(AWS_ERROR_OOM); |
200 | } |
201 | *ptr = newptr; |
202 | return AWS_OP_SUCCESS; |
203 | } |
204 | |
205 | /* Since the allocator doesn't support realloc, we'll need to emulate it (inefficiently). */ |
206 | if (oldsize >= newsize) { |
207 | return AWS_OP_SUCCESS; |
208 | } |
209 | |
210 | void *newptr = allocator->mem_acquire(allocator, newsize); |
211 | if (!newptr) { |
212 | return aws_raise_error(AWS_ERROR_OOM); |
213 | } |
214 | |
215 | memcpy(newptr, *ptr, oldsize); |
216 | memset((uint8_t *)newptr + oldsize, 0, newsize - oldsize); |
217 | |
218 | aws_mem_release(allocator, *ptr); |
219 | |
220 | *ptr = newptr; |
221 | |
222 | return AWS_OP_SUCCESS; |
223 | } |
224 | |
225 | /* Wraps a CFAllocator around aws_allocator. For Mac only. */ |
226 | #ifdef __MACH__ |
227 | |
228 | static CFStringRef s_cf_allocator_description = CFSTR("CFAllocator wrapping aws_allocator." ); |
229 | |
230 | /* note we don't have a standard specification stating sizeof(size_t) == sizeof(void *) so we have some extra casts */ |
231 | static void *s_cf_allocator_allocate(CFIndex alloc_size, CFOptionFlags hint, void *info) { |
232 | (void)hint; |
233 | |
234 | struct aws_allocator *allocator = info; |
235 | |
236 | void *mem = aws_mem_acquire(allocator, (size_t)alloc_size + sizeof(size_t)); |
237 | |
238 | if (!mem) { |
239 | return NULL; |
240 | } |
241 | |
242 | size_t allocation_size = (size_t)alloc_size + sizeof(size_t); |
243 | memcpy(mem, &allocation_size, sizeof(size_t)); |
244 | return (void *)((uint8_t *)mem + sizeof(size_t)); |
245 | } |
246 | |
247 | static void s_cf_allocator_deallocate(void *ptr, void *info) { |
248 | struct aws_allocator *allocator = info; |
249 | |
250 | void *original_allocation = (uint8_t *)ptr - sizeof(size_t); |
251 | |
252 | aws_mem_release(allocator, original_allocation); |
253 | } |
254 | |
255 | static void *s_cf_allocator_reallocate(void *ptr, CFIndex new_size, CFOptionFlags hint, void *info) { |
256 | (void)hint; |
257 | |
258 | struct aws_allocator *allocator = info; |
259 | AWS_ASSERT(allocator->mem_realloc); |
260 | |
261 | void *original_allocation = (uint8_t *)ptr - sizeof(size_t); |
262 | size_t original_size = 0; |
263 | memcpy(&original_size, original_allocation, sizeof(size_t)); |
264 | |
265 | if (aws_mem_realloc(allocator, &original_allocation, original_size, (size_t)new_size)) { |
266 | return NULL; |
267 | } |
268 | |
269 | size_t new_allocation_size = (size_t)new_size; |
270 | memcpy(original_allocation, &new_allocation_size, sizeof(size_t)); |
271 | |
272 | return (void *)((uint8_t *)original_allocation + sizeof(size_t)); |
273 | } |
274 | |
275 | static CFStringRef s_cf_allocator_copy_description(const void *info) { |
276 | (void)info; |
277 | |
278 | return s_cf_allocator_description; |
279 | } |
280 | |
281 | static CFIndex s_cf_allocator_preferred_size(CFIndex size, CFOptionFlags hint, void *info) { |
282 | (void)hint; |
283 | (void)info; |
284 | |
285 | return size + sizeof(size_t); |
286 | } |
287 | |
288 | CFAllocatorRef aws_wrapped_cf_allocator_new(struct aws_allocator *allocator) { |
289 | CFAllocatorRef cf_allocator = NULL; |
290 | |
291 | CFAllocatorReallocateCallBack reallocate_callback = NULL; |
292 | |
293 | if (allocator->mem_realloc) { |
294 | reallocate_callback = s_cf_allocator_reallocate; |
295 | } |
296 | |
297 | CFAllocatorContext context = { |
298 | .allocate = s_cf_allocator_allocate, |
299 | .copyDescription = s_cf_allocator_copy_description, |
300 | .deallocate = s_cf_allocator_deallocate, |
301 | .reallocate = reallocate_callback, |
302 | .info = allocator, |
303 | .preferredSize = s_cf_allocator_preferred_size, |
304 | .release = NULL, |
305 | .retain = NULL, |
306 | .version = 0, |
307 | }; |
308 | |
309 | cf_allocator = CFAllocatorCreate(NULL, &context); |
310 | |
311 | if (!cf_allocator) { |
312 | aws_raise_error(AWS_ERROR_OOM); |
313 | } |
314 | |
315 | return cf_allocator; |
316 | } |
317 | |
318 | void aws_wrapped_cf_allocator_destroy(CFAllocatorRef allocator) { |
319 | CFRelease(allocator); |
320 | } |
321 | |
322 | #endif /*__MACH__ */ |
323 | |