1 /*-------------------------------------------------------------------------
2  *
3  * memdebug.h
4  *	  Memory debugging support.
5  *
6  * Currently, this file either wraps <valgrind/memcheck.h> or substitutes
7  * empty definitions for Valgrind client request macros we use.
8  *
9  *
10  * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
11  * Portions Copyright (c) 1994, Regents of the University of California
12  *
13  * src/include/utils/memdebug.h
14  *
15  *-------------------------------------------------------------------------
16  */
17 #ifndef MEMDEBUG_H
18 #define MEMDEBUG_H
19 
20 #ifdef USE_VALGRIND
21 #include <valgrind/memcheck.h>
22 #else
23 #define VALGRIND_CHECK_MEM_IS_DEFINED(addr, size)			do {} while (0)
24 #define VALGRIND_CREATE_MEMPOOL(context, redzones, zeroed)	do {} while (0)
25 #define VALGRIND_DESTROY_MEMPOOL(context)					do {} while (0)
26 #define VALGRIND_MAKE_MEM_DEFINED(addr, size)				do {} while (0)
27 #define VALGRIND_MAKE_MEM_NOACCESS(addr, size)				do {} while (0)
28 #define VALGRIND_MAKE_MEM_UNDEFINED(addr, size)				do {} while (0)
29 #define VALGRIND_MEMPOOL_ALLOC(context, addr, size)			do {} while (0)
30 #define VALGRIND_MEMPOOL_FREE(context, addr)				do {} while (0)
31 #define VALGRIND_MEMPOOL_CHANGE(context, optr, nptr, size)	do {} while (0)
32 #endif
33 
34 
35 #ifdef CLOBBER_FREED_MEMORY
36 
37 /* Wipe freed memory for debugging purposes */
38 static inline void
39 wipe_mem(void *ptr, size_t size)
40 {
41 	VALGRIND_MAKE_MEM_UNDEFINED(ptr, size);
42 	memset(ptr, 0x7F, size);
43 	VALGRIND_MAKE_MEM_NOACCESS(ptr, size);
44 }
45 
46 #endif							/* CLOBBER_FREED_MEMORY */
47 
48 #ifdef MEMORY_CONTEXT_CHECKING
49 
50 static inline void
51 set_sentinel(void *base, Size offset)
52 {
53 	char	   *ptr = (char *) base + offset;
54 
55 	VALGRIND_MAKE_MEM_UNDEFINED(ptr, 1);
56 	*ptr = 0x7E;
57 	VALGRIND_MAKE_MEM_NOACCESS(ptr, 1);
58 }
59 
60 static inline bool
61 sentinel_ok(const void *base, Size offset)
62 {
63 	const char *ptr = (const char *) base + offset;
64 	bool		ret;
65 
66 	VALGRIND_MAKE_MEM_DEFINED(ptr, 1);
67 	ret = *ptr == 0x7E;
68 	VALGRIND_MAKE_MEM_NOACCESS(ptr, 1);
69 
70 	return ret;
71 }
72 
73 #endif							/* MEMORY_CONTEXT_CHECKING */
74 
75 #ifdef RANDOMIZE_ALLOCATED_MEMORY
76 
77 void		randomize_mem(char *ptr, size_t size);
78 
79 #endif							/* RANDOMIZE_ALLOCATED_MEMORY */
80 
81 
82 #endif							/* MEMDEBUG_H */
83