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
|
#include <assert.h>
#include <stdckdint.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include "alloc.h"
#include "errors.h"
[[noreturn]] static void oom(jmp_buf *env);
void *
heap_alloc(allocator_t mem, alloc_mode_t mode, void *ptr, ptrdiff_t oldnmemb,
ptrdiff_t newnmemb, ptrdiff_t elemsz, ptrdiff_t align)
{
void *p;
ptrdiff_t oldsz, newsz;
switch (mode) {
case ALLOC_NEW:
if (ckd_mul(&newsz, newnmemb, elemsz))
oom(mem.err);
/* Malloc is guaranteed to return a pointer aligned to an
alignment that is suitable for all fundamental types. For
larger alignments we need to use specialized functionality. */
if ((size_t)align <= alignof(max_align_t)) {
if ((p = malloc(newsz)) == nullptr)
oom(mem.err);
} else {
if ((p = aligned_alloc(align, newsz)) == nullptr)
oom(mem.err);
}
return p;
case ALLOC_RESIZE:
if (ckd_mul(&newsz, newnmemb, elemsz))
oom(mem.err);
if (ckd_mul(&oldsz, oldnmemb, elemsz))
oom(mem.err);
if ((size_t)align <= alignof(max_align_t)) {
if ((p = realloc(ptr, newsz)) == nullptr)
oom(mem.err);
} else {
/* We were allocated using aligned_alloc(). Unfortunately
there is no way to reallocate a buffer aligned via
aligned_alloc() so we need to allocate a new buffer and do
a manual copy… */
if ((p = aligned_alloc(align, newsz)) == nullptr)
oom(mem.err);
memcpy(p, ptr, oldsz);
#if 0
/* We would rather use free_aligned_size(), but it isn’t
available yet on most systems. */
free_aligned_sized(ptr, align, oldsz);
#else
free(ptr);
#endif
}
return p;
case ALLOC_FREE:
free(ptr);
return nullptr;
case ALLOC_FREEALL:
assert(!"Not implemented");
return nullptr;
default:
unreachable();
}
}
void
oom(jmp_buf *env)
{
if (env != nullptr)
longjmp(*env, 1);
err("heap_alloc:");
}
|
