Integrating android support.

src/android_mbstowcs.h

@@ -0,0 +1,36 @@
+/*
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program 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 General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+  (See COPYING.txt)
+*/
+
+/*
+Why we need android_wchar.h here?
+Actually, Android NDK has wchar.h header file, and implements related functions.
+However, it is likely that Bionic C library implements those funtions in a very simple 
+(or wrong ?) way on old Android devices ( API < 21), while they come to work on the new Android devices (API >= 21).
+Thus, tuxpaint im.c file depends on "mbstowcs" function which cannot work properly on old Android devices.
+Anyway, using our own implementation of "mbstowcs" can fix this problem.
+*/
+#ifndef TUXPAINT_ANDROID_SUPPORT_MBSTOWCS_H
+#define TUXPAINT_ANDROID_SUPPORT_MBSTOWCS_H
+
+#include <wchar.h>
+
+#undef mbsrtowcs
+
+// redefine mbstowcs function
+size_t mbstowcs(wchar_t * __restrict pwcs, const char * __restrict s, size_t n);
+
+#endif