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Diffstat (limited to 'sysdeps/unix/sysv/linux/i386/brk.c')
-rw-r--r--sysdeps/unix/sysv/linux/i386/brk.c49
1 files changed, 49 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/i386/brk.c b/sysdeps/unix/sysv/linux/i386/brk.c
new file mode 100644
index 0000000000..9963e0777b
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/i386/brk.c
@@ -0,0 +1,49 @@
+/* brk system call for Linux/i386.
+Copyright (C) 1995 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 Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <errno.h>
+#include <unistd.h>
+#include <sysdep.h>
+
+void *__curbrk;
+
+int
+__brk (void *addr)
+{
+  void *newbrk, *scratch;
+
+  asm ("movl %%ebx, %1\n"	/* Save %ebx in scratch register.  */
+       "movl %3, %%ebx\n"	/* Put ADDR in %ebx to be syscall arg.  */
+       "int $0x80 # %2\n"	/* Perform the system call.  */
+       "movl %1, %%ebx\n"	/* Restore %ebx from scratch register.  */
+       : "=a" (newbrk), "=r" (scratch)
+       : "0" (SYS_ify (brk)), "g" (addr));
+
+  __curbrk = newbrk;
+
+  if (newbrk < addr)
+    {
+      errno = ENOMEM;
+      return -1;
+    }
+
+  return 0;
+}
+weak_alias (__brk, brk)
+