1 /*
2 * Copyright (c) 2009-2021, Google LLC
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 * * Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * * Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * * Neither the name of Google LLC nor the
13 * names of its contributors may be used to endorse or promote products
14 * derived from this software without specific prior written permission.
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 Google LLC BE LIABLE FOR ANY DIRECT,
20 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
23 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 #ifndef UPB_MEM_ALLOC_H_
29 #define UPB_MEM_ALLOC_H_
30
31 // Must be last.
32 #include "upb/port/def.inc"
33
34 #ifdef __cplusplus
35 extern "C" {
36 #endif
37
38 typedef struct upb_alloc upb_alloc;
39
40 /* A combined `malloc()`/`free()` function.
41 * If `size` is 0 then the function acts like `free()`, otherwise it acts like
42 * `realloc()`. Only `oldsize` bytes from a previous allocation are
43 * preserved. */
44 typedef void* upb_alloc_func(upb_alloc* alloc, void* ptr, size_t oldsize,
45 size_t size);
46
47 /* A upb_alloc is a possibly-stateful allocator object.
48 *
49 * It could either be an arena allocator (which doesn't require individual
50 * `free()` calls) or a regular `malloc()` (which does). The client must
51 * therefore free memory unless it knows that the allocator is an arena
52 * allocator. */
53 struct upb_alloc {
54 upb_alloc_func* func;
55 };
56
upb_malloc(upb_alloc * alloc,size_t size)57 UPB_INLINE void* upb_malloc(upb_alloc* alloc, size_t size) {
58 UPB_ASSERT(alloc);
59 return alloc->func(alloc, NULL, 0, size);
60 }
61
upb_realloc(upb_alloc * alloc,void * ptr,size_t oldsize,size_t size)62 UPB_INLINE void* upb_realloc(upb_alloc* alloc, void* ptr, size_t oldsize,
63 size_t size) {
64 UPB_ASSERT(alloc);
65 return alloc->func(alloc, ptr, oldsize, size);
66 }
67
upb_free(upb_alloc * alloc,void * ptr)68 UPB_INLINE void upb_free(upb_alloc* alloc, void* ptr) {
69 UPB_ASSERT(alloc);
70 alloc->func(alloc, ptr, 0, 0);
71 }
72
73 // The global allocator used by upb. Uses the standard malloc()/free().
74
75 extern upb_alloc upb_alloc_global;
76
77 /* Functions that hard-code the global malloc.
78 *
79 * We still get benefit because we can put custom logic into our global
80 * allocator, like injecting out-of-memory faults in debug/testing builds. */
81
upb_gmalloc(size_t size)82 UPB_INLINE void* upb_gmalloc(size_t size) {
83 return upb_malloc(&upb_alloc_global, size);
84 }
85
upb_grealloc(void * ptr,size_t oldsize,size_t size)86 UPB_INLINE void* upb_grealloc(void* ptr, size_t oldsize, size_t size) {
87 return upb_realloc(&upb_alloc_global, ptr, oldsize, size);
88 }
89
upb_gfree(void * ptr)90 UPB_INLINE void upb_gfree(void* ptr) { upb_free(&upb_alloc_global, ptr); }
91
92 #ifdef __cplusplus
93 } /* extern "C" */
94 #endif
95
96 #include "upb/port/undef.inc"
97
98 #endif /* UPB_MEM_ALLOC_H_ */
99