1 /* Change data segment.  Linux generic version.
2    Copyright (C) 2020-2021 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C 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    The GNU C 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 the GNU C Library.  If not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #include <errno.h>
20 #include <unistd.h>
21 #include <sysdep.h>
22 
23 /* This must be initialized data because commons can't have aliases.  */
24 void *__curbrk = 0;
25 
26 #if HAVE_INTERNAL_BRK_ADDR_SYMBOL
27 /* Old braindamage in GCC's crtstuff.c requires this symbol in an attempt
28    to work around different old braindamage in the old Linux ELF dynamic
29    linker.  */
weak_alias(__curbrk,___brk_addr)30 weak_alias (__curbrk, ___brk_addr)
31 #endif
32 
33 int
34 __brk (void *addr)
35 {
36   __curbrk = (void *) INTERNAL_SYSCALL_CALL (brk, addr);
37   if (__curbrk < addr)
38     {
39       __set_errno (ENOMEM);
40       return -1;
41     }
42 
43   return 0;
44 }
45 weak_alias (__brk, brk)
46