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1 #ifndef MALLOC_GLUE_H
2 #define MALLOC_GLUE_H
3 
4 #include <stdint.h>
5 #include <sys/mman.h>
6 #include <pthread.h>
7 #include <unistd.h>
8 #include <elf.h>
9 #include <string.h>
10 #include "atomic.h"
11 #include "syscall.h"
12 #include "libc.h"
13 #include "lock.h"
14 #include "dynlink.h"
15 
16 // use macros to appropriately namespace these.
17 #define size_classes __malloc_size_classes
18 #define ctx __malloc_context
19 #define alloc_meta __malloc_alloc_meta
20 #define is_allzero __malloc_allzerop
21 #define dump_heap __dump_heap
22 
23 #define malloc __libc_malloc_impl
24 #define realloc __libc_realloc
25 #define free __libc_free
26 
27 #if USE_REAL_ASSERT
28 #include <assert.h>
29 #else
30 #undef assert
31 #define assert(x) do { if (!(x)) a_crash(); } while(0)
32 #endif
33 
34 #define brk(p) ((uintptr_t)__syscall(SYS_brk, p))
35 
36 #define mmap __mmap
37 #define madvise __madvise
38 #define mremap __mremap
39 
40 #define DISABLE_ALIGNED_ALLOC (__malloc_replaced && !__aligned_alloc_replaced)
41 
get_random_secret()42 static inline uint64_t get_random_secret()
43 {
44 	uint64_t secret = (uintptr_t)&secret * 1103515245;
45 	for (size_t i=0; libc.auxv[i]; i+=2)
46 		if (libc.auxv[i]==AT_RANDOM)
47 			memcpy(&secret, (char *)libc.auxv[i+1]+8, sizeof secret);
48 	return secret;
49 }
50 
51 #ifndef PAGESIZE
52 #define PAGESIZE PAGE_SIZE
53 #endif
54 
55 #define MT (libc.need_locks)
56 
57 #define RDLOCK_IS_EXCLUSIVE 1
58 
59 __attribute__((__visibility__("hidden")))
60 extern int __malloc_lock[1];
61 
62 #define LOCK_OBJ_DEF \
63 int __malloc_lock[1]; \
64 void __malloc_atfork(int who) { malloc_atfork(who); }
65 
rdlock()66 static inline void rdlock()
67 {
68 	if (MT) LOCK(__malloc_lock);
69 }
wrlock()70 static inline void wrlock()
71 {
72 	if (MT) LOCK(__malloc_lock);
73 }
unlock()74 static inline void unlock()
75 {
76 	UNLOCK(__malloc_lock);
77 }
upgradelock()78 static inline void upgradelock()
79 {
80 }
resetlock()81 static inline void resetlock()
82 {
83 	__malloc_lock[0] = 0;
84 }
85 
malloc_atfork(int who)86 static inline void malloc_atfork(int who)
87 {
88 	if (who<0) rdlock();
89 	else if (who>0) resetlock();
90 	else unlock();
91 }
92 
93 #endif
94