blob: 3ba2e4da432b410595808b9ebed03759ab5eabd9 (
plain)
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
|
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
/*********************************************************************/
/* AllocaCheck */
/*********************************************************************/
/* check for alloca overruns (which otherwise are hard to track down
and often only repro on optimized builds).
USAGE:
void foo() {
ALLOCA_CHECK(); // Declare at function level scope
....
void* mem = ALLOCA(size); // does an alloca,
} // destructor of ALLOCA_CHECK for buffer overruns.
*/
/* */
/*********************************************************************/
#ifndef AllocaCheck_h
#define AllocaCheck_h
#include <malloc.h> // for alloca itself
#if defined(assert) && !defined(_ASSERTE)
#define _ASSERTE assert
#endif
#if defined(_DEBUG) || defined(DEBUG)
/*********************************************************************/
class AllocaCheck {
public:
enum { CheckBytes = 0xCCCDCECF,
};
struct AllocaSentinal {
int check;
AllocaSentinal* next;
};
public:
/***************************************************/
AllocaCheck() {
sentinals = 0;
}
~AllocaCheck() {
AllocaSentinal* ptr = sentinals;
while (ptr != 0) {
if (ptr->check != (int)CheckBytes)
_ASSERTE(!"alloca buffer overrun");
ptr = ptr->next;
}
}
void* add(void* allocaBuff, unsigned size) {
AllocaSentinal* newSentinal = (AllocaSentinal*) ((char*) allocaBuff + size);
newSentinal->check = CheckBytes;
newSentinal->next = sentinals;
sentinals = newSentinal;
memset(allocaBuff, 0xDD, size);
return allocaBuff;
}
private:
AllocaSentinal* sentinals;
};
#define ALLOCA_CHECK() AllocaCheck __allocaChecker
#define ALLOCA(size) __allocaChecker.add(_alloca(size+sizeof(AllocaCheck::AllocaSentinal)), size);
#else
#define ALLOCA_CHECK()
#define ALLOCA(size) _alloca(size)
#endif
#endif
|
