keyboard add ability to specify temporary custom layouts

rb core allows you to load custom keyboard layouts

this patch adds the ability to load a keyboard layout in a buffer
the custom layout is temporary and does not overwrite the current layout

use like so:

    unsigned short kbd[64];
    unsigned short *kbd_p = kbd;
    if (!kbd_create_layout("ABCD1234\n", kbd, sizeof(kbd)))
        kbd_p = NULL;

    rb->kbd_input(buf,sizeof(buf), kbd_p);

Change-Id: I7be2bd4a1b4797a147fa70228a9749dc56ac052a

3 files changed, 92 insertions, 0 deletions

diff --git a/apps/plugins/lib/SOURCES b/apps/plugins/lib/SOURCES
index 9a7aef51d0..1149f35bac 100644
--- a/apps/plugins/lib/SOURCES
+++ b/apps/plugins/lib/SOURCES
@@ -69,6 +69,8 @@ bmp_smooth_scale.c
 pluginlib_albumart.c
 #endif
 
+kbd_helper.c
+
 #endif /* HAVE_LCD_BITMAP */
 
 #ifdef HAVE_TOUCHSCREEN
diff --git a/apps/plugins/lib/kbd_helper.c b/apps/plugins/lib/kbd_helper.c
new file mode 100644
index 0000000000..00191c3532
--- /dev/null
+++ b/apps/plugins/lib/kbd_helper.c
@@ -0,0 +1,63 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2020 William Wilgus
+ *
+ * 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#include "plugin.h"
+#include "kbd_helper.h"
+
+/*  USAGE:
+    unsigned short kbd[64];
+    unsigned short *kbd_p = kbd;
+    if (!kbd_create_layout("ABCD1234\n", kbd, sizeof(kbd)))
+        kbd_p = NULL;
+
+    rb->kbd_input(buf,sizeof(buf), kbd_p);
+*/
+
+/* create a custom keyboard layout for kbd_input
+ * success returns size of buffer used
+ * failure returns 0
+*/
+int kbd_create_layout(char *layout, unsigned short *buf, int bufsz)
+{
+    unsigned short *pbuf;
+    const unsigned char *p = layout;
+    int len = 0;
+    pbuf = buf;
+    while (*p && (pbuf - buf + 8) < bufsz)
+    {
+        p = rb->utf8decode(p, &pbuf[len+1]);
+        if (pbuf[len+1] == '\n')
+        {
+            *pbuf = len;
+            pbuf += len+1;
+            len = 0;
+        }
+        else
+            len++;
+    }
+
+    if (len+1 < bufsz)
+    {
+        *pbuf = len;
+        pbuf[len+1] = 0xFEFF;   /* mark end of characters */
+        return len + 1;
+    }
+    return 0;
+}
diff --git a/apps/plugins/lib/kbd_helper.h b/apps/plugins/lib/kbd_helper.h
new file mode 100644
index 0000000000..90443cbf3f
--- /dev/null
+++ b/apps/plugins/lib/kbd_helper.h
@@ -0,0 +1,27 @@
+/***************************************************************************
+ *             __________               __   ___.                  
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___  
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /  
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <   
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \  
+ *                     \/            \/     \/    \/            \/ 
+ * $Id$
+ *
+ * Copyright (C) 2020 William Wilgus
+ *
+ * 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#ifndef KBD_HELPER_H
+#define KBD_HELPER_H
+
+/* create a custom keyboard layout for kbd_input */
+int kbd_create_layout(char *layout, unsigned short *buf, int bufsz);
+
+#endif /* KBD_HELPER_H */