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-rw-r--r--debug/strcpy_chk.c68
1 files changed, 68 insertions, 0 deletions
diff --git a/debug/strcpy_chk.c b/debug/strcpy_chk.c
new file mode 100644
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--- /dev/null
+++ b/debug/strcpy_chk.c
@@ -0,0 +1,68 @@
+/* Copyright (C) 1991, 1997, 2000, 2003, 2004 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 <stddef.h>
+#include <string.h>
+#include <memcopy.h>
+
+#undef strcpy
+
+/* Copy SRC to DEST with checking of destination buffer overflow.  */
+char *
+__strcpy_chk (dest, src, destlen)
+     char *dest;
+     const char *src;
+     size_t destlen;
+{
+  reg_char c;
+  char *s = (char *) src;
+  const ptrdiff_t off = dest - s;
+
+  while (__builtin_expect (destlen >= 4, 0))
+    {
+      c = s[0];
+      s[off] = c;
+      if (c == '\0')
+        return dest;
+      c = s[1];
+      s[off + 1] = c;
+      if (c == '\0')
+        return dest;
+      c = s[2];
+      s[off + 2] = c;
+      if (c == '\0')
+        return dest;
+      c = s[3];
+      s[off + 3] = c;
+      if (c == '\0')
+        return dest;
+      destlen -= 4;
+      s += 4;
+    }
+
+  do
+    {
+      if (__builtin_expect (destlen-- == 0, 0))
+        __chk_fail ();
+      c = *s;
+      *(s++ + off) = c;
+    }
+  while (c != '\0');
+
+  return dest;
+}