Commit | Line | Data |
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b27f8e75 MD |
1 | /* |
2 | * Copyright (C) 2009 Pierre-Marc Fournier | |
1622ba22 | 3 | * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
c39c72ee PMF |
4 | * |
5 | * This library is free software; you can redistribute it and/or | |
6 | * modify it under the terms of the GNU Lesser General Public | |
7 | * License as published by the Free Software Foundation; either | |
8 | * version 2.1 of the License, or (at your option) any later version. | |
9 | * | |
10 | * This library is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
13 | * Lesser General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU Lesser General Public | |
16 | * License along with this library; if not, write to the Free Software | |
17 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
18 | */ | |
19 | ||
e541a28d PMF |
20 | #define _GNU_SOURCE |
21 | #include <dlfcn.h> | |
22 | #include <sys/types.h> | |
23 | #include <stdio.h> | |
4c3536e0 MD |
24 | #include <urcu/system.h> |
25 | #include <urcu/uatomic.h> | |
1622ba22 MD |
26 | |
27 | #define TRACEPOINT_DEFINE | |
28 | #define TRACEPOINT_CREATE_PROBES | |
29 | #include "ust_libc.h" | |
fbd8191b | 30 | |
f95b2888 SS |
31 | #define STATIC_CALLOC_LEN 4096 |
32 | static char static_calloc_buf[STATIC_CALLOC_LEN]; | |
4c3536e0 | 33 | static unsigned long static_calloc_buf_offset; |
f95b2888 SS |
34 | |
35 | static void *static_calloc(size_t nmemb, size_t size) | |
36 | { | |
4c3536e0 | 37 | unsigned long prev_offset, new_offset, res_offset; |
f95b2888 | 38 | |
4c3536e0 MD |
39 | /* |
40 | * Protect static_calloc_buf_offset from concurrent updates | |
41 | * using a cmpxchg loop rather than a mutex to remove a | |
42 | * dependency on pthread. This will minimize the risk of bad | |
43 | * interaction between mutex and malloc instrumentation. | |
44 | */ | |
45 | res_offset = CMM_LOAD_SHARED(static_calloc_buf_offset); | |
46 | do { | |
47 | prev_offset = res_offset; | |
48 | if (nmemb * size > sizeof(static_calloc_buf) - prev_offset) { | |
49 | return NULL; | |
50 | } | |
51 | new_offset = prev_offset + nmemb * size; | |
52 | } while ((res_offset = uatomic_cmpxchg(&static_calloc_buf_offset, | |
53 | prev_offset, new_offset)) != prev_offset); | |
f95b2888 SS |
54 | return &static_calloc_buf[prev_offset]; |
55 | } | |
56 | ||
e541a28d PMF |
57 | void *malloc(size_t size) |
58 | { | |
f95b2888 | 59 | static void *(*plibc_malloc)(size_t size); |
1c184644 PMF |
60 | void *retval; |
61 | ||
b27f8e75 | 62 | if (plibc_malloc == NULL) { |
e541a28d | 63 | plibc_malloc = dlsym(RTLD_NEXT, "malloc"); |
b27f8e75 | 64 | if (plibc_malloc == NULL) { |
e541a28d PMF |
65 | fprintf(stderr, "mallocwrap: unable to find malloc\n"); |
66 | return NULL; | |
67 | } | |
68 | } | |
1c184644 | 69 | retval = plibc_malloc(size); |
1622ba22 | 70 | tracepoint(ust_libc, malloc, size, retval); |
1c184644 PMF |
71 | return retval; |
72 | } | |
73 | ||
74 | void free(void *ptr) | |
75 | { | |
f95b2888 SS |
76 | static void (*plibc_free)(void *ptr); |
77 | ||
78 | /* Check whether the memory was allocated with | |
79 | * static_calloc, in which case there is nothing | |
80 | * to free. | |
81 | */ | |
82 | if ((char *)ptr >= static_calloc_buf && | |
83 | (char *)ptr < static_calloc_buf + STATIC_CALLOC_LEN) { | |
84 | return; | |
85 | } | |
1c184644 | 86 | |
b27f8e75 | 87 | if (plibc_free == NULL) { |
1c184644 | 88 | plibc_free = dlsym(RTLD_NEXT, "free"); |
b27f8e75 | 89 | if (plibc_free == NULL) { |
1c184644 | 90 | fprintf(stderr, "mallocwrap: unable to find free\n"); |
eb0f0951 | 91 | return; |
1c184644 PMF |
92 | } |
93 | } | |
1622ba22 | 94 | tracepoint(ust_libc, free, ptr); |
eb0f0951 | 95 | plibc_free(ptr); |
e541a28d | 96 | } |
f95b2888 SS |
97 | |
98 | void *calloc(size_t nmemb, size_t size) | |
99 | { | |
100 | static void *(*volatile plibc_calloc)(size_t nmemb, size_t size); | |
101 | void *retval; | |
102 | ||
103 | if (plibc_calloc == NULL) { | |
104 | /* | |
105 | * Temporarily redirect to static_calloc, | |
106 | * until the dlsym lookup has completed. | |
107 | */ | |
108 | plibc_calloc = static_calloc; | |
109 | plibc_calloc = dlsym(RTLD_NEXT, "calloc"); | |
110 | if (plibc_calloc == NULL) { | |
111 | fprintf(stderr, "callocwrap: unable to find calloc\n"); | |
112 | return NULL; | |
113 | } | |
114 | } | |
115 | retval = plibc_calloc(nmemb, size); | |
116 | tracepoint(ust_libc, calloc, nmemb, size, retval); | |
117 | return retval; | |
118 | } | |
119 | ||
120 | void *realloc(void *ptr, size_t size) | |
121 | { | |
122 | static void *(*plibc_realloc)(void *ptr, size_t size); | |
123 | void *retval; | |
124 | ||
125 | if (plibc_realloc == NULL) { | |
126 | plibc_realloc = dlsym(RTLD_NEXT, "realloc"); | |
127 | if (plibc_realloc == NULL) { | |
128 | fprintf(stderr, "reallocwrap: unable to find realloc\n"); | |
129 | return NULL; | |
130 | } | |
131 | } | |
132 | retval = plibc_realloc(ptr, size); | |
133 | tracepoint(ust_libc, realloc, ptr, size, retval); | |
134 | return retval; | |
135 | } | |
9d34b226 SS |
136 | |
137 | void *memalign(size_t alignment, size_t size) | |
138 | { | |
139 | static void *(*plibc_memalign)(size_t alignment, size_t size); | |
140 | void *retval; | |
141 | ||
142 | if (plibc_memalign == NULL) { | |
143 | plibc_memalign = dlsym(RTLD_NEXT, "memalign"); | |
144 | if (plibc_memalign == NULL) { | |
145 | fprintf(stderr, "memalignwrap: unable to find memalign\n"); | |
146 | return NULL; | |
147 | } | |
148 | } | |
149 | retval = plibc_memalign(alignment, size); | |
150 | tracepoint(ust_libc, memalign, alignment, size, retval); | |
151 | return retval; | |
152 | } | |
153 | ||
154 | int posix_memalign(void **memptr, size_t alignment, size_t size) | |
155 | { | |
156 | static int(*plibc_posix_memalign)(void **memptr, size_t alignment, size_t size); | |
157 | int retval; | |
158 | ||
159 | if (plibc_posix_memalign == NULL) { | |
160 | plibc_posix_memalign = dlsym(RTLD_NEXT, "posix_memalign"); | |
161 | if (plibc_posix_memalign == NULL) { | |
162 | fprintf(stderr, "posix_memalignwrap: unable to find posix_memalign\n"); | |
163 | return ENOMEM; | |
164 | } | |
165 | } | |
166 | retval = plibc_posix_memalign(memptr, alignment, size); | |
167 | tracepoint(ust_libc, posix_memalign, *memptr, alignment, size, retval); | |
168 | return retval; | |
169 | } |