1 /*
2 * Copyright (C) 2008 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in
12 * the documentation and/or other materials provided with the
13 * distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28 #include <unistd.h>
29 #include <errno.h>
30
31
32 #define SBRK_ALIGN 32
33
34 /* shared with brk() implementation */
35 char* __bionic_brk;
36
sbrk(ptrdiff_t increment)37 void *sbrk(ptrdiff_t increment)
38 {
39 char* start;
40 char* end;
41 char* new_brk;
42
43 if ( !__bionic_brk)
44 __bionic_brk = __brk((void*)0);
45
46 start = (char*)(((long)__bionic_brk + SBRK_ALIGN-1) & ~(SBRK_ALIGN-1));
47 end = start + increment;
48
49 new_brk = __brk(end);
50 if (new_brk == (void*)-1)
51 return new_brk;
52 else if (new_brk < end)
53 {
54 errno = ENOMEM;
55 return (void*)-1;
56 }
57
58 __bionic_brk = new_brk;
59 return start;
60 }
61