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Diffstat (limited to 'libc/sysdeps/linux/common/sbrk.c')
-rw-r--r--libc/sysdeps/linux/common/sbrk.c47
1 files changed, 47 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/common/sbrk.c b/libc/sysdeps/linux/common/sbrk.c
new file mode 100644
index 000000000..028370e99
--- /dev/null
+++ b/libc/sysdeps/linux/common/sbrk.c
@@ -0,0 +1,47 @@
+/* Copyright (C) 1991, 1995, 1996, 1997, 2000 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <unistd.h>
+#include <errno.h>
+
+/* Defined in brk.c. */
+extern void *__curbrk;
+extern int brk (void *addr);
+
+
+/* Extend the process's data space by INCREMENT.
+ If INCREMENT is negative, shrink data space by - INCREMENT.
+ Return start of new space allocated, or -1 for errors. */
+void * sbrk (intptr_t increment)
+{
+ void *oldbrk;
+
+ if (__curbrk == NULL)
+ if (brk (0) < 0) /* Initialize the break. */
+ return (void *) -1;
+
+ if (increment == 0)
+ return __curbrk;
+
+ oldbrk = __curbrk;
+ if (brk (oldbrk + increment) < 0)
+ return (void *) -1;
+
+ return oldbrk;
+}
+