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-rw-r--r--debug/gets_chk.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/debug/gets_chk.c b/debug/gets_chk.c
new file mode 100644
index 0000000000..3715a39672
--- /dev/null
+++ b/debug/gets_chk.c
@@ -0,0 +1,77 @@
+/* Copyright (C) 1993, 1996, 1997, 1998, 2002, 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.
+
+   As a special exception, if you link the code in this file with
+   files compiled with a GNU compiler to produce an executable,
+   that does not cause the resulting executable to be covered by
+   the GNU Lesser General Public License.  This exception does not
+   however invalidate any other reasons why the executable file
+   might be covered by the GNU Lesser General Public License.
+   This exception applies to code released by its copyright holders
+   in files containing the exception.  */
+
+#include "../libio/libioP.h"
+#include <limits.h>
+
+char *
+__gets_chk (char *buf, size_t size)
+{
+  _IO_size_t count;
+  int ch;
+  char *retval;
+
+  if (size == 0)
+    __chk_fail ();
+
+  _IO_acquire_lock (_IO_stdin);
+  ch = _IO_getc_unlocked (_IO_stdin);
+  if (ch == EOF)
+    {
+      retval = NULL;
+      goto unlock_return;
+    }
+  if (ch == '\n')
+    count = 0;
+  else
+    {
+      /* This is very tricky since a file descriptor may be in the
+	 non-blocking mode. The error flag doesn't mean much in this
+	 case. We return an error only when there is a new error. */
+      int old_error = _IO_stdin->_IO_file_flags & _IO_ERR_SEEN;
+      _IO_stdin->_IO_file_flags &= ~_IO_ERR_SEEN;
+      buf[0] = (char) ch;
+      count = INTUSE(_IO_getline) (_IO_stdin, buf + 1, size - 1, '\n', 0) + 1;
+      if (_IO_stdin->_IO_file_flags & _IO_ERR_SEEN)
+	{
+	  retval = NULL;
+	  goto unlock_return;
+	}
+      else
+	_IO_stdin->_IO_file_flags |= old_error;
+    }
+  if (count >= size)
+    __chk_fail ();
+  buf[count] = 0;
+  retval = buf;
+unlock_return:
+  _IO_release_lock (_IO_stdin);
+  return retval;
+}
+
+link_warning (__gets_chk, "the `gets' function is dangerous and should not be used.")