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-rw-r--r--sysdeps/nacl/brk.c93
1 files changed, 0 insertions, 93 deletions
diff --git a/sysdeps/nacl/brk.c b/sysdeps/nacl/brk.c
deleted file mode 100644
index cf7aac4b20..0000000000
--- a/sysdeps/nacl/brk.c
+++ /dev/null
@@ -1,93 +0,0 @@
-/* brk -- Adjust the "break" at the end of initial data. NaCl version.
- Copyright (C) 2015-2016 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <http://www.gnu.org/licenses/>. */
-
-#include <errno.h>
-#include <libc-internal.h>
-#include <stdint.h>
-#include <sys/mman.h>
-#include <sys/param.h>
-#include <unistd.h>
-
-/* sbrk.c expects this. */
-void *__curbrk;
-
-static uintptr_t
-page_above (void *addr)
-{
- return ALIGN_UP ((uintptr_t) addr, EXEC_PAGESIZE);
-}
-
-/* Set the end of the process's data space to ADDR.
- Return 0 if successful, -1 if not. */
-int
-__brk (void *addr)
-{
- /* The NaCl sysbrk call is deprecated, so we do not use it here. Other
- libc code expects that __sbrk can be used at least a little bit, so
- rather than a plain stub we have a minimal __brk implementation here.
- It just uses mmap/munmap to grow or shrink the break area, punting as
- soon as mmap fails to use the same contiguous area. */
-
- if (__glibc_unlikely (__curbrk == NULL))
- {
- /* This is the first call. We must initialize the record
- of the current position. It starts out at the end of the
- main program's data segment. */
-
- /* XXX dynamic case??? */
- extern char _end[];
- __curbrk = _end;
- }
-
- if (__glibc_unlikely (addr == NULL))
- /* This is a call just to ensure that __curbrk is set up. */
- return 0;
-
- uintptr_t old_limit = page_above (__curbrk);
- uintptr_t new_limit = page_above (addr);
-
- if (old_limit > new_limit)
- {
- /* We're shrinking the old heap enough to release some pages. */
- if (__munmap ((void *) new_limit, old_limit - new_limit) != 0)
- return -1;
- }
- else if (old_limit < new_limit)
- {
- /* We're growing the old heap enough to need some more pages.
- See if they are available. */
- void *new_space = __mmap ((void *) old_limit, new_limit - old_limit,
- PROT_READ | PROT_WRITE, MAP_ANON, -1, 0);
- if (new_space != (void *) old_limit)
- {
- if (new_space != MAP_FAILED)
- {
- /* mmap chose some different place for the pages
- because the contiguous area was not available.
- Oh well. We can't use that. */
- __munmap (new_space, new_limit - old_limit);
- __set_errno (ENOMEM);
- }
- return -1;
- }
- }
-
- __curbrk = addr;
- return 0;
-}
-weak_alias (__brk, brk)