File: bson-memory.c

package info (click to toggle)
libmongodb-perl 1.4.5-1
  • links: PTS, VCS
  • area: main
  • in suites: stretch
  • size: 7,004 kB
  • ctags: 2,932
  • sloc: perl: 12,511; ansic: 9,566; makefile: 22
file content (288 lines) | stat: -rw-r--r-- 6,553 bytes parent folder | download
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
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
/*
 * Copyright 2013 MongoDB, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


#include <stdlib.h>
#include <string.h>

#include "bson-atomic.h"
#include "bson-config.h"
#include "bson-memory.h"


static bson_mem_vtable_t gMemVtable = {
   malloc,
   calloc,
#ifdef __APPLE__
   reallocf,
#else
   realloc,
#endif
   free,
};


/*
 *--------------------------------------------------------------------------
 *
 * bson_malloc --
 *
 *       Allocates @num_bytes of memory and returns a pointer to it.  If
 *       malloc failed to allocate the memory, abort() is called.
 *
 *       Libbson does not try to handle OOM conditions as it is beyond the
 *       scope of this library to handle so appropriately.
 *
 * Parameters:
 *       @num_bytes: The number of bytes to allocate.
 *
 * Returns:
 *       A pointer if successful; otherwise abort() is called and this
 *       function will never return.
 *
 * Side effects:
 *       None.
 *
 *--------------------------------------------------------------------------
 */

void *
bson_malloc (size_t num_bytes) /* IN */
{
   void *mem;

   if (!(mem = gMemVtable.malloc (num_bytes))) {
      abort ();
   }

   return mem;
}


/*
 *--------------------------------------------------------------------------
 *
 * bson_malloc0 --
 *
 *       Like bson_malloc() except the memory is zeroed first. This is
 *       similar to calloc() except that abort() is called in case of
 *       failure to allocate memory.
 *
 * Parameters:
 *       @num_bytes: The number of bytes to allocate.
 *
 * Returns:
 *       A pointer if successful; otherwise abort() is called and this
 *       function will never return.
 *
 * Side effects:
 *       None.
 *
 *--------------------------------------------------------------------------
 */

void *
bson_malloc0 (size_t num_bytes) /* IN */
{
   void *mem = NULL;

   if (BSON_LIKELY (num_bytes)) {
      if (BSON_UNLIKELY (!(mem = gMemVtable.calloc (1, num_bytes)))) {
         abort ();
      }
   }

   return mem;
}


/*
 *--------------------------------------------------------------------------
 *
 * bson_realloc --
 *
 *       This function behaves similar to realloc() except that if there is
 *       a failure abort() is called.
 *
 * Parameters:
 *       @mem: The memory to realloc, or NULL.
 *       @num_bytes: The size of the new allocation or 0 to free.
 *
 * Returns:
 *       The new allocation if successful; otherwise abort() is called and
 *       this function never returns.
 *
 * Side effects:
 *       None.
 *
 *--------------------------------------------------------------------------
 */

void *
bson_realloc (void   *mem,        /* IN */
              size_t  num_bytes)  /* IN */
{
   /*
    * Not all platforms are guaranteed to free() the memory if a call to
    * realloc() with a size of zero occurs. Windows, Linux, and FreeBSD do,
    * however, OS X does not.
    */
   if (BSON_UNLIKELY (num_bytes == 0)) {
      gMemVtable.free (mem);
      return NULL;
   }

   mem = gMemVtable.realloc (mem, num_bytes);

   if (BSON_UNLIKELY (!mem)) {
      abort ();
   }

   return mem;
}


/*
 *--------------------------------------------------------------------------
 *
 * bson_realloc_ctx --
 *
 *       This wraps bson_realloc and provides a compatible api for similar
 *       functions with a context
 *
 * Parameters:
 *       @mem: The memory to realloc, or NULL.
 *       @num_bytes: The size of the new allocation or 0 to free.
 *       @ctx: Ignored
 *
 * Returns:
 *       The new allocation if successful; otherwise abort() is called and
 *       this function never returns.
 *
 * Side effects:
 *       None.
 *
 *--------------------------------------------------------------------------
 */


void *
bson_realloc_ctx (void   *mem,        /* IN */
                  size_t  num_bytes,  /* IN */
                  void   *ctx)        /* IN */
{
   return bson_realloc (mem, num_bytes);
}


/*
 *--------------------------------------------------------------------------
 *
 * bson_free --
 *
 *       Frees @mem using the underlying allocator.
 *
 *       Currently, this only calls free() directly, but that is subject to
 *       change.
 *
 * Parameters:
 *       @mem: An allocation to free.
 *
 * Returns:
 *       None.
 *
 * Side effects:
 *       None.
 *
 *--------------------------------------------------------------------------
 */

void
bson_free (void *mem) /* IN */
{
   gMemVtable.free (mem);
}


/*
 *--------------------------------------------------------------------------
 *
 * bson_zero_free --
 *
 *       Frees @mem using the underlying allocator. @size bytes of @mem will
 *       be zeroed before freeing the memory. This is useful in scenarios
 *       where @mem contains passwords or other sensitive information.
 *
 * Parameters:
 *       @mem: An allocation to free.
 *       @size: The number of bytes in @mem.
 *
 * Returns:
 *       None.
 *
 * Side effects:
 *       None.
 *
 *--------------------------------------------------------------------------
 */

void
bson_zero_free (void  *mem,  /* IN */
                size_t size) /* IN */
{
   if (BSON_LIKELY (mem)) {
      memset (mem, 0, size);
      gMemVtable.free (mem);
   }
}


/*
 *--------------------------------------------------------------------------
 *
 * bson_mem_set_vtable --
 *
 *       This function will change our allocationt vtable.
 *
 *       It is imperitive that this is called at the beginning of the
 *       process before any memory has been allocated by the default
 *       allocator.
 *
 * Returns:
 *       None.
 *
 * Side effects:
 *       None.
 *
 *--------------------------------------------------------------------------
 */

void
bson_mem_set_vtable (const bson_mem_vtable_t *vtable)
{
   bson_return_if_fail (vtable);

   if (!vtable->malloc ||
       !vtable->calloc ||
       !vtable->realloc ||
       !vtable->free) {
      fprintf (stderr, "Failure to install BSON vtable, "
                       "missing functions.\n");
      return;
   }

   gMemVtable = *vtable;
}