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-rw-r--r--libc/unistd/sbrk.c60
1 files changed, 60 insertions, 0 deletions
diff --git a/libc/unistd/sbrk.c b/libc/unistd/sbrk.c
new file mode 100644
index 0000000..a112b6c
--- /dev/null
+++ b/libc/unistd/sbrk.c
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#include <unistd.h>
+#include <errno.h>
+
+
+#define SBRK_ALIGN 32
+
+/* shared with brk() implementation */
+char* __bionic_brk;
+
+void *sbrk(ptrdiff_t increment)
+{
+ char* start;
+ char* end;
+ char* new_brk;
+
+ if ( !__bionic_brk)
+ __bionic_brk = __brk((void*)0);
+
+ start = (char*)(((long)__bionic_brk + SBRK_ALIGN-1) & ~(SBRK_ALIGN-1));
+ end = start + increment;
+
+ new_brk = __brk(end);
+ if (new_brk == (void*)-1)
+ return new_brk;
+ else if (new_brk < end)
+ {
+ errno = ENOMEM;
+ return (void*)-1;
+ }
+
+ __bionic_brk = new_brk;
+ return start;
+}