Fix another memory leak on malloc fail

lib/helius_microrl/microrl.c:476:22: error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]

LICENSE

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+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    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 3 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, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<http://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<http://www.gnu.org/philosophy/why-not-lgpl.html>.

README.md

@@ -1,4 +1,4 @@
-# I237 Hardware Programming
+# I237 Door Access program
 
 This here is my repository for hardware programming course at
 Estonian IT College that is based around a
@@ -39,3 +39,24 @@ git checkout lab02
 ```
 
 Don't forget to `make clean` after each checkout!
+
+# License
+
+```Text
+Copyright (C) 2016 Arti Zirk <arti.zirk@gmail.com>
+
+This file is part of I237 Door Access program.
+
+I237 Door Access 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 3 of the License, or
+(at your option) any later version.
+
+I237 Door Access 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 I237 Door Access.  If not, see <http://www.gnu.org/licenses/>.
+```

doc/arduino-mega-rfid-rc522-wiring.markdown

@@ -0,0 +1,25 @@
+# Arduino Mega RFID-RC522 wiring
+
+## Introduction
+
+**NB! RFID-RC522 requires only 3.3 V DC input voltage. Never connect it to 5V input.**
+
+<div class=pagebreak></div>
+
+## Wiring illustration
+
+![arduino-mega-rfid-rc522-wiring.png](arduino-mega-rfid-rc522-wiring.png)
+
+## Wiring table
+
+| Signal | ATMega2560 port and pin | Arduino Mega 2560 pin | 5V to 3V converter | RFID-RC522 | Wire colour in illustration |
+| --- | --- | --- | --- | --- |  --- |
+| Slave select | PORTB 0 | 53 | - | SDA | White |
+| SPI clock | PORTB 1 | 52 | - | SCK | Orange |
+| Master out slave in | PORTB 2 | 51 | - | MOSI | Green |
+| Master in slave out | PORTB 3 | 50 | - | MISO | Yellow |
+| RF522 reset | PORTL 0 | 49 | - | RST | Brown |
+| Ground | GND | GND | GND | GND | Black |
+| 5 V DC | - | 5V | VIN | - | Red |
+| 3,3 V DC | - | - | VOUT | 3.3 V | Red |
+

lib/helius_microrl/LICENSE

@@ -0,0 +1,165 @@
+                   GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
+
+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+  "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+  An "Application" is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
+Defining a subclass of a class defined by the Library is deemed a mode
+of using an interface provided by the Library.
+
+  A "Combined Work" is a work produced by combining or linking an
+Application with the Library.  The particular version of the Library
+with which the Combined Work was made is also called the "Linked
+Version".
+
+  The "Minimal Corresponding Source" for a Combined Work means the
+Corresponding Source for the Combined Work, excluding any source code
+for portions of the Combined Work that, considered in isolation, are
+based on the Application, and not on the Linked Version.
+
+  The "Corresponding Application Code" for a Combined Work means the
+object code and/or source code for the Application, including any data
+and utility programs needed for reproducing the Combined Work from the
+Application, but excluding the System Libraries of the Combined Work.
+
+  1. Exception to Section 3 of the GNU GPL.
+
+  You may convey a covered work under sections 3 and 4 of this License
+without being bound by section 3 of the GNU GPL.
+
+  2. Conveying Modified Versions.
+
+  If you modify a copy of the Library, and, in your modifications, a
+facility refers to a function or data to be supplied by an Application
+that uses the facility (other than as an argument passed when the
+facility is invoked), then you may convey a copy of the modified
+version:
+
+   a) under this License, provided that you make a good faith effort to
+   ensure that, in the event an Application does not supply the
+   function or data, the facility still operates, and performs
+   whatever part of its purpose remains meaningful, or
+
+   b) under the GNU GPL, with none of the additional permissions of
+   this License applicable to that copy.
+
+  3. Object Code Incorporating Material from Library Header Files.
+
+  The object code form of an Application may incorporate material from
+a header file that is part of the Library.  You may convey such object
+code under terms of your choice, provided that, if the incorporated
+material is not limited to numerical parameters, data structure
+layouts and accessors, or small macros, inline functions and templates
+(ten or fewer lines in length), you do both of the following:
+
+   a) Give prominent notice with each copy of the object code that the
+   Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the object code with a copy of the GNU GPL and this license
+   document.
+
+  4. Combined Works.
+
+  You may convey a Combined Work under terms of your choice that,
+taken together, effectively do not restrict modification of the
+portions of the Library contained in the Combined Work and reverse
+engineering for debugging such modifications, if you also do each of
+the following:
+
+   a) Give prominent notice with each copy of the Combined Work that
+   the Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the Combined Work with a copy of the GNU GPL and this license
+   document.
+
+   c) For a Combined Work that displays copyright notices during
+   execution, include the copyright notice for the Library among
+   these notices, as well as a reference directing the user to the
+   copies of the GNU GPL and this license document.
+
+   d) Do one of the following:
+
+       0) Convey the Minimal Corresponding Source under the terms of this
+       License, and the Corresponding Application Code in a form
+       suitable for, and under terms that permit, the user to
+       recombine or relink the Application with a modified version of
+       the Linked Version to produce a modified Combined Work, in the
+       manner specified by section 6 of the GNU GPL for conveying
+       Corresponding Source.
+
+       1) Use a suitable shared library mechanism for linking with the
+       Library.  A suitable mechanism is one that (a) uses at run time
+       a copy of the Library already present on the user's computer
+       system, and (b) will operate properly with a modified version
+       of the Library that is interface-compatible with the Linked
+       Version.
+
+   e) Provide Installation Information, but only if you would otherwise
+   be required to provide such information under section 6 of the
+   GNU GPL, and only to the extent that such information is
+   necessary to install and execute a modified version of the
+   Combined Work produced by recombining or relinking the
+   Application with a modified version of the Linked Version. (If
+   you use option 4d0, the Installation Information must accompany
+   the Minimal Corresponding Source and Corresponding Application
+   Code. If you use option 4d1, you must provide the Installation
+   Information in the manner specified by section 6 of the GNU GPL
+   for conveying Corresponding Source.)
+
+  5. Combined Libraries.
+
+  You may place library facilities that are a work based on the
+Library side by side in a single library together with other library
+facilities that are not Applications and are not covered by this
+License, and convey such a combined library under terms of your
+choice, if you do both of the following:
+
+   a) Accompany the combined library with a copy of the same work based
+   on the Library, uncombined with any other library facilities,
+   conveyed under the terms of this License.
+
+   b) Give prominent notice with the combined library that part of it
+   is a work based on the Library, and explaining where to find the
+   accompanying uncombined form of the same work.
+
+  6. Revised Versions of the GNU Lesser General Public License.
+
+  The Free Software Foundation may publish revised and/or new versions
+of the GNU Lesser General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
+
+  Each version is given a distinguishing version number. If the
+Library as you received it specifies that a certain numbered version
+of the GNU Lesser General Public License "or any later version"
+applies to it, you have the option of following the terms and
+conditions either of that published version or of any later version
+published by the Free Software Foundation. If the Library as you
+received it does not specify a version number of the GNU Lesser
+General Public License, you may choose any version of the GNU Lesser
+General Public License ever published by the Free Software Foundation.
+
+  If the Library as you received it specifies that a proxy can decide
+whether future versions of the GNU Lesser General Public License shall
+apply, that proxy's public statement of acceptance of any version is
+permanent authorization for you to choose that version for the
+Library.

lib/helius_microrl/README

@@ -0,0 +1,103 @@
+microrl - micro read line library for small and embedded devices with basic VT100 support.
+
+1. DESCRIPTION
+
+Microrl library is designed to help implement command line interface in small and embedded devices. Main goal is to write compact, small memory consuming but powerful interfaces, with support navigation through command line with cursor, HOME, END keys, hot key like Ctrl+U and other, history and completion feature.
+
+
+2. FEATURE
+
+	** config.h file
+	 - Turn on/off feature for add functional/decrease memory via config files.
+
+	** hot keys support
+	 - backspace, cursor arrow, HOME, END keys
+	 - Ctrl+U (cut line from cursor to begin) 
+	 - Ctrl+K (cut line from cursor to end) 
+	 - Ctrl+A (like HOME) 
+	 - Ctrl+E (like END)
+	 - Ctrl+H (like backspace)
+	 - Ctrl+B (like cursor arrow left) 
+	 - Ctrl+F (like cursor arrow right)
+	 - Ctrl+P (like cursor arrow up)
+	 - Ctrl+N (like cursor arrow down)
+	 - Ctrl+C (call 'sigint' callback, only for embedded system)
+
+	** history
+	 - Static ring buffer history for memory saving. Number of commands saved to history depends from commands length and buffer size (defined in config)
+
+	** completion
+	 - via completion callback
+
+
+3. SRC STRUCTURE
+
+src/             - library source
+  microrl.c      - microrl routines
+  microrl.h      - lib interface and data type
+  config.h       - customisation config-file
+examples/        - library usage examples
+  avr_misc/      - avr specific routines for avr example
+  unix_misc/     - unix specific routines for desktop example
+  example.c      - common part of example, for build  demonstrating example for various platform
+  example_misc.h - interface to platform specific routines for example build (avr, unix)
+  Makefile       - unix example build (gcc)
+  Makefile.avr   - avr example build (avr-gcc)
+
+
+4. INSTALL
+
+Requirements: C compiler with support for C99 standard (GNU GCC, Keil, IAR) with standard C library (libc, uClibc or other compatible). Also you have to implement several routines in your own code for library to work. 
+NOTE: need add -std=gnu99 arg for gcc
+
+For embed lib to you project, you need to do few simple steps:
+
+a) Include microrl.h file to you project.
+
+b) Create 'microrl_t' object, and call 'microrl_init' func, with print callback pointer. Print callback pointer is pointer to function that call by library if it's need to put text to terminal. Text string always is null terminated.
+For example on linux PC print callback may be:
+	// print callback for microrl library
+	void print (char * str)
+	{
+		fprintf (stdout, "%s", str);
+	}
+
+c) Call 'microrl_set_execute_callback' with pointer to you routine, what will be called if user press enter in terminal. Execute callback give a 'argc', 'argv' parametrs, like 'main' func in application. All token in 'argv' is null terminated. So you can simply walk through argv and handle commands.
+
+d) If you want completion support if user press TAB key, call 'microrl_set_complete_callback' and set you callback. It also give 'argc' and 'argv' arguments, so iterate through it and return set of complete variants. 
+
+e) Look at 'config.h' file, for tune library for you requiring. 
+
+f) Now you just call 'microrl_insert_char' on each char received from input stream (usart, network, etc).
+
+Example of code:
+
+	//*****************************************************************************
+	int main (int argc, char ** argv)
+	{
+		// create microrl object and pointer on it
+		microrl_t rl;
+		microrl_t * prl = &rl;
+		// call init with ptr to microrl instance and print callback
+		microrl_init (prl, print);
+		// set callback for execute
+		microrl_set_execute_callback (prl, execute);
+		// set callback for completion (optionally)
+		microrl_set_complete_callback (prl, complet);
+		// set callback for ctrl+c handling (optionally)
+		microrl_set_sigint_callback (prl, sigint);
+		
+		while (1) {
+			// put received char from stdin to microrl lib
+			char ch = get_char ();
+			microrl_insert_char (prl, ch);
+		}
+		return 0;
+	}
+
+See examples library usage.
+
+
+
+Author: Eugene Samoylov aka Helius (ghelius@gmail.com) 
+01.09.2011

lib/helius_microrl/config.h

@@ -0,0 +1,104 @@
+/*
+Microrl library config files
+Autor: Eugene Samoylov aka Helius (ghelius@gmail.com)
+*/
+#ifndef _MICRORL_CONFIG_H_
+#define _MICRORL_CONFIG_H_
+
+#define MICRORL_LIB_VER "1.5.1"
+
+/*********** CONFIG SECTION **************/
+/*
+Command line length, define cmdline buffer size. Set max number of chars + 1,
+because last byte of buffer need to contain '\0' - NULL terminator, and 
+not use for storing inputed char.
+If user input chars more then it parametrs-1, chars not added to command line.*/
+#define _COMMAND_LINE_LEN (1+100)									// for 32 chars
+
+/*
+Command token number, define max token it command line, if number of token 
+typed in command line exceed this value, then prints message about it and
+command line not to be parced and 'execute' callback will not calls.
+Token is word separate by white space, for example 3 token line:
+"IRin> set mode test" */
+#define _COMMAND_TOKEN_NMB 8
+
+/*
+Define you prompt string here. You can use colors escape code, for highlight you prompt,
+for example this prompt will green color (if you terminal supports color)*/
+//#define _PROMPT_DEFAULT "\033[32mIRin >\033[0m "	// green color
+//#define _PROMPT_DEFAULT "IRin > "
+#define _PROMPT_DEFAULT ">"
+
+/*
+Define prompt text (without ESC sequence, only text) prompt length, it needs because if you use
+ESC sequence, it's not possible detect only text length*/
+#define _PROMPT_LEN       1
+
+/*Define it, if you wanna use completion functional, also set completion callback in you code,
+now if user press TAB calls 'copmlitetion' callback. If you no need it, you can just set 
+NULL to callback ptr and do not use it, but for memory saving tune, 
+if you are not going to use it - disable this define.*/
+//#define _USE_COMPLETE
+
+/*Define it, if you wanna use history. It s work's like bash history, and
+set stored value to cmdline, if UP and DOWN key pressed. Using history add
+memory consuming, depends from _RING_HISTORY_LEN parametr */
+//#define _USE_HISTORY
+
+/*
+History ring buffer length, define static buffer size.
+For saving memory, each entered cmdline store to history in ring buffer,
+so we can not say, how many line we can store, it depends from cmdline len,
+but memory using more effective. We not prefer dinamic memory allocation for
+small and embedded devices. Overhead is 2 char on each saved line*/
+//#define _RING_HISTORY_LEN 64
+
+/*
+Enable Handling terminal ESC sequence. If disabling, then cursor arrow, HOME, END will not work,
+use Ctrl+A(B,F,P,N,A,E,H,K,U,C) see README, but decrease code memory.*/
+//#define _USE_ESC_SEQ
+
+/*
+Use snprintf from you standard complier library, but it gives some overhead.
+If not defined, use my own u16int_to_str variant, it's save about 800 byte of code size
+on AVR (avr-gcc build).
+Try to build with and without, and compare total code size for tune library.
+*/
+#define _USE_LIBC_STDIO
+
+/*
+Enable 'interrupt signal' callback, if user press Ctrl+C */
+//#define _USE_CTLR_C
+
+/*
+Print prompt at 'microrl_init', if enable, prompt will print at startup, 
+otherwise first prompt will print after first press Enter in terminal
+NOTE!: Enable it, if you call 'microrl_init' after your communication subsystem 
+already initialize and ready to print message */
+#define _ENABLE_INIT_PROMPT
+
+/*
+New line symbol */
+#define _ENDL_CR
+
+#if defined(_ENDL_CR)
+#define ENDL "\r"
+#elif defined(_ENDL_CRLF)
+#define ENDL "\r\n"
+#elif defined(_ENDL_LF)
+#define ENDL "\n"
+#elif defined(_ENDL_LFCR)
+#define ENDL "\n\r"
+#else
+#error "You must define new line symbol."
+#endif
+
+/********** END CONFIG SECTION ************/
+
+
+#if _RING_HISTORY_LEN > 256
+#error "This history implementation (ring buffer with 1 byte iterator) allow 256 byte buffer size maximum"
+#endif
+
+#endif

lib/helius_microrl/microrl.c

@@ -0,0 +1,684 @@
+/*
+Author: Samoylov Eugene aka Helius (ghelius@gmail.com)
+BUGS and TODO:
+-- add echo_off feature
+-- rewrite history for use more than 256 byte buffer
+*/
+
+#include <string.h>
+#include <ctype.h>
+#include <stdlib.h>
+#include "microrl.h"
+#ifdef _USE_LIBC_STDIO
+#include <stdio.h>
+#endif
+
+//#define DBG(...) fprintf(stderr, "\033[33m");fprintf(stderr,__VA_ARGS__);fprintf(stderr,"\033[0m");
+
+char * prompt_default = _PROMPT_DEFAULT;
+
+#ifdef _USE_HISTORY
+
+#ifdef _HISTORY_DEBUG
+//*****************************************************************************
+// print buffer content on screen
+static void print_hist (ring_history_t * pThis)
+{
+	printf ("\n");
+	for (int i = 0; i < _RING_HISTORY_LEN; i++) {
+		if (i == pThis->begin)
+			printf ("b");
+		else 
+			printf (" ");
+	}
+	printf ("\n");
+	for (int i = 0; i < _RING_HISTORY_LEN; i++) {
+		if (isalpha(pThis->ring_buf[i]))
+			printf ("%c", pThis->ring_buf[i]);
+		else 
+			printf ("%d", pThis->ring_buf[i]);
+	}
+	printf ("\n");
+	for (int i = 0; i < _RING_HISTORY_LEN; i++) {
+		if (i == pThis->end)
+			printf ("e");
+		else 
+			printf (" ");
+	}
+	printf ("\n");
+}
+#endif
+
+//*****************************************************************************
+// remove older message from ring buffer
+static void hist_erase_older (ring_history_t * pThis)
+{
+	int new_pos = pThis->begin + pThis->ring_buf [pThis->begin] + 1;
+	if (new_pos >= _RING_HISTORY_LEN)
+		new_pos = new_pos - _RING_HISTORY_LEN;
+	
+	pThis->begin = new_pos;
+}
+
+//*****************************************************************************
+// check space for new line, remove older while not space
+static int hist_is_space_for_new (ring_history_t * pThis, int len)
+{
+	if (pThis->ring_buf [pThis->begin] == 0)
+		return true;
+	if (pThis->end >= pThis->begin) {
+		if (_RING_HISTORY_LEN - pThis->end + pThis->begin - 1 > len)
+			return true;
+	}	else {
+		if (pThis->begin - pThis->end - 1> len)
+			return true;
+	}
+	return false;
+}
+
+//*****************************************************************************
+// put line to ring buffer
+static void hist_save_line (ring_history_t * pThis, char * line, int len)
+{
+	if (len > _RING_HISTORY_LEN - 2)
+		return;
+	while (!hist_is_space_for_new (pThis, len)) {
+		hist_erase_older (pThis);
+	}
+	// if it's first line
+	if (pThis->ring_buf [pThis->begin] == 0) 
+		pThis->ring_buf [pThis->begin] = len;
+	
+	// store line
+	if (len < _RING_HISTORY_LEN-pThis->end-1)
+		memcpy (pThis->ring_buf + pThis->end + 1, line, len);
+	else {
+		int part_len = _RING_HISTORY_LEN-pThis->end-1;
+		memcpy (pThis->ring_buf + pThis->end + 1, line, part_len);
+		memcpy (pThis->ring_buf, line + part_len, len - part_len);
+	}
+	pThis->ring_buf [pThis->end] = len;
+	pThis->end = pThis->end + len + 1;
+	if (pThis->end >= _RING_HISTORY_LEN)
+		pThis->end -= _RING_HISTORY_LEN;
+	pThis->ring_buf [pThis->end] = 0;
+	pThis->cur = 0;
+#ifdef _HISTORY_DEBUG
+	print_hist (pThis);
+#endif
+}
+
+//*****************************************************************************
+// copy saved line to 'line' and return size of line
+static int hist_restore_line (ring_history_t * pThis, char * line, int dir)
+{
+	int cnt = 0;
+	// count history record	
+	int header = pThis->begin;
+	while (pThis->ring_buf [header] != 0) {
+		header += pThis->ring_buf [header] + 1;
+		if (header >= _RING_HISTORY_LEN)
+			header -= _RING_HISTORY_LEN; 
+		cnt++;
+	}
+
+	if (dir == _HIST_UP) {
+		if (cnt >= pThis->cur) {
+			int header = pThis->begin;
+			int j = 0;
+			// found record for 'pThis->cur' index
+			while ((pThis->ring_buf [header] != 0) && (cnt - j -1 != pThis->cur)) {
+				header += pThis->ring_buf [header] + 1;
+				if (header >= _RING_HISTORY_LEN)
+					header -= _RING_HISTORY_LEN;
+				j++;
+			}
+			if (pThis->ring_buf[header]) {
+					pThis->cur++;
+				// obtain saved line
+				if (pThis->ring_buf [header] + header < _RING_HISTORY_LEN) {
+					memset (line, 0, _COMMAND_LINE_LEN);
+					memcpy (line, pThis->ring_buf + header + 1, pThis->ring_buf[header]);
+				} else {
+					int part0 = _RING_HISTORY_LEN - header - 1;
+					memset (line, 0, _COMMAND_LINE_LEN);
+					memcpy (line, pThis->ring_buf + header + 1, part0);
+					memcpy (line + part0, pThis->ring_buf, pThis->ring_buf[header] - part0);
+				}
+				return pThis->ring_buf[header];
+			}
+		}
+	} else {
+		if (pThis->cur > 0) {
+				pThis->cur--;
+			int header = pThis->begin;
+			int j = 0;
+
+			while ((pThis->ring_buf [header] != 0) && (cnt - j != pThis->cur)) {
+				header += pThis->ring_buf [header] + 1;
+				if (header >= _RING_HISTORY_LEN)
+					header -= _RING_HISTORY_LEN;
+				j++;
+			}
+			if (pThis->ring_buf [header] + header < _RING_HISTORY_LEN) {
+				memcpy (line, pThis->ring_buf + header + 1, pThis->ring_buf[header]);
+			} else {
+				int part0 = _RING_HISTORY_LEN - header - 1;
+				memcpy (line, pThis->ring_buf + header + 1, part0);
+				memcpy (line + part0, pThis->ring_buf, pThis->ring_buf[header] - part0);
+			}
+			return pThis->ring_buf[header];
+		} else {
+			/* empty line */
+			return 0;
+		}
+	}
+	return -1;
+}
+#endif
+
+
+
+
+
+
+
+
+//*****************************************************************************
+// split cmdline to tkn array and return nmb of token
+static int split (microrl_t * pThis, int limit, char const ** tkn_arr)
+{
+	int i = 0;
+	int ind = 0;
+	while (1) {
+		// go to the first whitespace (zerro for us)
+		while ((pThis->cmdline [ind] == '\0') && (ind < limit)) {
+			ind++;
+		}
+		if (!(ind < limit)) return i;
+		tkn_arr[i++] = pThis->cmdline + ind;
+		if (i >= _COMMAND_TOKEN_NMB) {
+			return -1;
+		}
+		// go to the first NOT whitespace (not zerro for us)
+		while ((pThis->cmdline [ind] != '\0') && (ind < limit)) {
+			ind++;
+		}
+		if (!(ind < limit)) return i;
+	}
+	return i;
+}
+
+
+//*****************************************************************************
+inline static void print_prompt (microrl_t * pThis)
+{
+	pThis->print (pThis->prompt_str);
+}
+
+//*****************************************************************************
+inline static void terminal_backspace (microrl_t * pThis)
+{
+		pThis->print ("\033[D \033[D");
+}
+
+//*****************************************************************************
+inline static void terminal_newline (microrl_t * pThis)
+{
+	pThis->print (ENDL);
+}
+
+#ifndef _USE_LIBC_STDIO
+//*****************************************************************************
+// convert 16 bit value to string
+// 0 value not supported!!! just make empty string
+// Returns pointer to a buffer tail
+static char *u16bit_to_str (unsigned int nmb, char * buf)
+{
+	char tmp_str [6] = {0,};
+	int i = 0, j;
+	if (nmb <= 0xFFFF) {
+		while (nmb > 0) {
+			tmp_str[i++] = (nmb % 10) + '0';
+			nmb /=10;
+		}
+		for (j = 0; j < i; ++j)
+			*(buf++) = tmp_str [i-j-1];
+	}
+	*buf = '\0';
+	return buf;
+}
+#endif
+
+
+//*****************************************************************************
+// set cursor at position from begin cmdline (after prompt) + offset
+static void terminal_move_cursor (microrl_t * pThis, int offset)
+{
+	char str[16] = {0,};
+#ifdef _USE_LIBC_STDIO 
+	if (offset > 0) {
+		snprintf (str, 16, "\033[%dC", offset);
+	} else if (offset < 0) {
+		snprintf (str, 16, "\033[%dD", -(offset));
+	}
+#else 
+	char *endstr;
+	strcpy (str, "\033[");
+	if (offset > 0) {
+		endstr = u16bit_to_str (offset, str+2);
+		strcpy (endstr, "C");
+	} else if (offset < 0) {
+		endstr = u16bit_to_str (-(offset), str+2);
+		strcpy (endstr, "D");
+	} else
+		return;
+#endif	
+	pThis->print (str);
+}
+
+//*****************************************************************************
+static void terminal_reset_cursor (microrl_t * pThis)
+{
+	char str[16];
+#ifdef _USE_LIBC_STDIO
+	snprintf (str, 16, "\033[%dD\033[%dC", \
+						_COMMAND_LINE_LEN + _PROMPT_LEN + 2, _PROMPT_LEN);
+
+#else
+	char *endstr;
+	strcpy (str, "\033[");
+	endstr = u16bit_to_str ( _COMMAND_LINE_LEN + _PROMPT_LEN + 2,str+2);
+	strcpy (endstr, "D\033["); endstr += 3;
+	endstr = u16bit_to_str (_PROMPT_LEN, endstr);
+	strcpy (endstr, "C");
+#endif
+	pThis->print (str);
+}
+
+//*****************************************************************************
+// print cmdline to screen, replace '\0' to wihitespace 
+static void terminal_print_line (microrl_t * pThis, int pos, int cursor)
+{
+	pThis->print ("\033[K");    // delete all from cursor to end
+
+	char nch [] = {0,0};
+	int i;
+	for (i = pos; i < pThis->cmdlen; i++) {
+		nch [0] = pThis->cmdline [i];
+		if (nch[0] == '\0')
+			nch[0] = ' ';
+		pThis->print (nch);
+	}
+	
+	terminal_reset_cursor (pThis);
+	terminal_move_cursor (pThis, cursor);
+}
+
+//*****************************************************************************
+void microrl_init (microrl_t * pThis, void (*print) (const char *)) 
+{
+	memset(pThis->cmdline, 0, _COMMAND_LINE_LEN);
+#ifdef _USE_HISTORY
+	memset(pThis->ring_hist.ring_buf, 0, _RING_HISTORY_LEN);
+	pThis->ring_hist.begin = 0;
+	pThis->ring_hist.end = 0;
+	pThis->ring_hist.cur = 0;
+#endif
+	pThis->cmdlen =0;
+	pThis->cursor = 0;
+	pThis->execute = NULL;
+	pThis->get_completion = NULL;
+#ifdef _USE_CTLR_C
+	pThis->sigint = NULL;
+#endif
+	pThis->prompt_str = prompt_default;
+	pThis->print = print;
+#ifdef _ENABLE_INIT_PROMPT
+	print_prompt (pThis);
+#endif
+}
+
+//*****************************************************************************
+void microrl_set_complete_callback (microrl_t * pThis, char ** (*get_completion)(int, const char* const*))
+{
+	pThis->get_completion = get_completion;
+}
+
+//*****************************************************************************
+void microrl_set_execute_callback (microrl_t * pThis, int (*execute)(int, const char* const*))
+{
+	pThis->execute = execute;
+}
+#ifdef _USE_CTLR_C
+//*****************************************************************************
+void microrl_set_sigint_callback (microrl_t * pThis, void (*sigintf)(void))
+{
+	pThis->sigint = sigintf;
+}
+#endif
+
+#ifdef _USE_ESC_SEQ
+static void hist_search (microrl_t * pThis, int dir)
+{
+	int len = hist_restore_line (&pThis->ring_hist, pThis->cmdline, dir);
+	if (len >= 0) {
+		pThis->cursor = pThis->cmdlen = len;
+		terminal_reset_cursor (pThis);
+		terminal_print_line (pThis, 0, pThis->cursor);
+	}
+}
+
+//*****************************************************************************
+// handling escape sequences
+static int escape_process (microrl_t * pThis, char ch)
+{
+	if (ch == '[') {
+		pThis->escape_seq = _ESC_BRACKET;
+		return 0;
+	} else if (pThis->escape_seq == _ESC_BRACKET) {
+		if (ch == 'A') {
+#ifdef _USE_HISTORY
+			hist_search (pThis, _HIST_UP);
+#endif
+			return 1;
+		} else if (ch == 'B') {
+#ifdef _USE_HISTORY
+			hist_search (pThis, _HIST_DOWN);
+#endif
+			return 1;
+		} else if (ch == 'C') {
+			if (pThis->cursor < pThis->cmdlen) {
+				terminal_move_cursor (pThis, 1);
+				pThis->cursor++;
+			}
+			return 1;
+		} else if (ch == 'D') {
+			if (pThis->cursor > 0) {
+				terminal_move_cursor (pThis, -1);
+				pThis->cursor--;
+			}
+			return 1;
+		} else if (ch == '7') {
+			pThis->escape_seq = _ESC_HOME;
+			return 0;
+		} else if (ch == '8') {
+			pThis->escape_seq = _ESC_END;
+			return 0;
+		} 
+	} else if (ch == '~') {
+		if (pThis->escape_seq == _ESC_HOME) {
+			terminal_reset_cursor (pThis);
+			pThis->cursor = 0;
+			return 1;
+		} else if (pThis->escape_seq == _ESC_END) {
+			terminal_move_cursor (pThis, pThis->cmdlen-pThis->cursor);
+			pThis->cursor = pThis->cmdlen;
+			return 1;
+		}
+	}
+
+	/* unknown escape sequence, stop */
+	return 1;
+}
+#endif
+
+//*****************************************************************************
+// insert len char of text at cursor position
+static int microrl_insert_text (microrl_t * pThis, char * text, int len)
+{
+	int i;
+	if (pThis->cmdlen + len < _COMMAND_LINE_LEN) {
+		memmove (pThis->cmdline + pThis->cursor + len,
+						 pThis->cmdline + pThis->cursor,
+						 pThis->cmdlen - pThis->cursor);
+		for (i = 0; i < len; i++) {
+			pThis->cmdline [pThis->cursor + i] = text [i];
+			if (pThis->cmdline [pThis->cursor + i] == ' ') {
+				pThis->cmdline [pThis->cursor + i] = 0;
+			}
+		}
+		pThis->cursor += len;
+		pThis->cmdlen += len;
+		pThis->cmdline [pThis->cmdlen] = '\0';
+		return true;
+	}
+	return false;
+}
+
+//*****************************************************************************
+// remove one char at cursor
+static void microrl_backspace (microrl_t * pThis)
+{
+	if (pThis->cursor > 0) {
+		terminal_backspace (pThis);
+		memmove (pThis->cmdline + pThis->cursor-1,
+						 pThis->cmdline + pThis->cursor,
+						 pThis->cmdlen-pThis->cursor+1);
+		pThis->cursor--;
+		pThis->cmdline [pThis->cmdlen] = '\0';
+		pThis->cmdlen--;
+	}
+}
+
+
+#ifdef _USE_COMPLETE
+
+//*****************************************************************************
+static int common_len (char ** arr)
+{
+	unsigned int i;
+	unsigned int j;
+	char *shortest = arr[0];
+	unsigned int shortlen = strlen(shortest);
+
+	for (i = 0; arr[i] != NULL; ++i)
+		if (strlen(arr[i]) < shortlen) {
+			shortest = arr[i];
+			shortlen = strlen(shortest);
+		}
+
+	for (i = 0; i < shortlen; ++i)
+		for (j = 0; arr[j] != 0; ++j)
+			if (shortest[i] != arr[j][i])
+				return i;
+
+	return i;
+}
+
+//*****************************************************************************
+static void microrl_get_complite (microrl_t * pThis) 
+{
+	char const * tkn_arr[_COMMAND_TOKEN_NMB];
+	char ** compl_token; 
+	
+	if (pThis->get_completion == NULL) // callback was not set
+		return;
+	
+	int status = split (pThis, pThis->cursor, tkn_arr);
+	if (pThis->cmdline[pThis->cursor-1] == '\0')
+		tkn_arr[status++] = "";
+	compl_token = pThis->get_completion (status, tkn_arr);
+	if (compl_token[0] != NULL) {
+		int i = 0;
+		int len;
+
+		if (compl_token[1] == NULL) {
+			len = strlen (compl_token[0]);
+		} else {
+			len = common_len (compl_token);
+			terminal_newline (pThis);
+			while (compl_token [i] != NULL) {
+				pThis->print (compl_token[i]);
+				pThis->print (" ");
+				i++;
+			}
+			terminal_newline (pThis);
+			print_prompt (pThis);
+		}
+		
+		if (len) {
+			microrl_insert_text (pThis, compl_token[0] + strlen(tkn_arr[status-1]), 
+																	len - strlen(tkn_arr[status-1]));
+			if (compl_token[1] == NULL) 
+				microrl_insert_text (pThis, " ", 1);
+		}
+		terminal_reset_cursor (pThis);
+		terminal_print_line (pThis, 0, pThis->cursor);
+	} 
+}
+#endif
+
+//*****************************************************************************
+void new_line_handler(microrl_t * pThis){
+	char const * tkn_arr [_COMMAND_TOKEN_NMB];
+	int status;
+
+	terminal_newline (pThis);
+#ifdef _USE_HISTORY
+	if (pThis->cmdlen > 0)
+		hist_save_line (&pThis->ring_hist, pThis->cmdline, pThis->cmdlen);
+#endif
+	status = split (pThis, pThis->cmdlen, tkn_arr);
+	if (status == -1){
+		//          pThis->print ("ERROR: Max token amount exseed\n");
+		pThis->print ("ERROR:too many tokens");
+		pThis->print (ENDL);
+	}
+	if ((status > 0) && (pThis->execute != NULL))
+		pThis->execute (status, tkn_arr);
+	print_prompt (pThis);
+	pThis->cmdlen = 0;
+	pThis->cursor = 0;
+	memset(pThis->cmdline, 0, _COMMAND_LINE_LEN);
+#ifdef _USE_HISTORY
+	pThis->ring_hist.cur = 0;
+#endif
+}
+
+//*****************************************************************************
+
+void microrl_insert_char (microrl_t * pThis, int ch)
+{
+#ifdef _USE_ESC_SEQ
+	if (pThis->escape) {
+		if (escape_process(pThis, ch))
+			pThis->escape = 0;
+	} else {
+#endif
+		switch (ch) {
+			//-----------------------------------------------------
+#ifdef _ENDL_CR
+			case KEY_CR:
+				new_line_handler(pThis);
+			break;
+			case KEY_LF:
+			break;
+#elif defined(_ENDL_CRLF)
+			case KEY_CR:
+				pThis->tmpch = KEY_CR;
+			break;
+			case KEY_LF:
+			if (pThis->tmpch == KEY_CR)
+				new_line_handler(pThis);
+			break;
+#elif defined(_ENDL_LFCR)
+			case KEY_LF:
+				pThis->tmpch = KEY_LF;
+			break;
+			case KEY_CR:
+			if (pThis->tmpch == KEY_LF)
+				new_line_handler(pThis);
+			break;
+#else
+			case KEY_CR:
+			break;
+			case KEY_LF:
+				new_line_handler(pThis);
+			break;
+#endif
+			//-----------------------------------------------------
+#ifdef _USE_COMPLETE
+			case KEY_HT:
+				microrl_get_complite (pThis);
+			break;
+#endif
+			//-----------------------------------------------------
+			case KEY_ESC:
+#ifdef _USE_ESC_SEQ
+				pThis->escape = 1;
+#endif
+			break;
+			//-----------------------------------------------------
+			case KEY_NAK: // ^U
+					while (pThis->cursor > 0) {
+					microrl_backspace (pThis);
+				}
+				terminal_print_line (pThis, 0, pThis->cursor);
+			break;
+			//-----------------------------------------------------
+			case KEY_VT:  // ^K
+				pThis->print ("\033[K");
+				pThis->cmdlen = pThis->cursor;
+			break;
+			//-----------------------------------------------------
+			case KEY_ENQ: // ^E
+				terminal_move_cursor (pThis, pThis->cmdlen-pThis->cursor);
+				pThis->cursor = pThis->cmdlen;
+			break;
+			//-----------------------------------------------------
+			case KEY_SOH: // ^A
+				terminal_reset_cursor (pThis);
+				pThis->cursor = 0;
+			break;
+			//-----------------------------------------------------
+			case KEY_ACK: // ^F
+			if (pThis->cursor < pThis->cmdlen) {
+				terminal_move_cursor (pThis, 1);
+				pThis->cursor++;
+			}
+			break;
+			//-----------------------------------------------------
+			case KEY_STX: // ^B
+			if (pThis->cursor) {
+				terminal_move_cursor (pThis, -1);
+				pThis->cursor--;
+			}
+			break;
+			//-----------------------------------------------------
+			case KEY_DLE: //^P
+#ifdef _USE_HISTORY
+			hist_search (pThis, _HIST_UP);
+#endif
+			break;
+			//-----------------------------------------------------
+			case KEY_SO: //^N
+#ifdef _USE_HISTORY
+			hist_search (pThis, _HIST_DOWN);
+#endif
+			break;
+			//-----------------------------------------------------
+			case KEY_DEL: // Backspace
+			case KEY_BS: // ^U
+				microrl_backspace (pThis);
+				terminal_print_line (pThis, pThis->cursor, pThis->cursor);
+			break;
+#ifdef _USE_CTLR_C
+			case KEY_ETX:
+			if (pThis->sigint != NULL)
+				pThis->sigint();
+			break;
+#endif
+			//-----------------------------------------------------
+			default:
+			if (((ch == ' ') && (pThis->cmdlen == 0)) || IS_CONTROL_CHAR(ch))
+				break;
+			if (microrl_insert_text (pThis, (char*)&ch, 1))
+				terminal_print_line (pThis, pThis->cursor-1, pThis->cursor);
+			
+			break;
+		}
+#ifdef _USE_ESC_SEQ
+	}
+#endif
+}

lib/helius_microrl/microrl.h

@@ -0,0 +1,117 @@
+#ifndef _MICRORL_H_
+#define _MICRORL_H_
+
+#include "config.h"
+
+#define true  1
+#define false 0
+
+ /* define the Key codes */
+#define KEY_NUL 0 /**< ^@ Null character */
+#define KEY_SOH 1 /**< ^A Start of heading, = console interrupt */
+#define KEY_STX 2 /**< ^B Start of text, maintenance mode on HP console */
+#define KEY_ETX 3 /**< ^C End of text */
+#define KEY_EOT 4 /**< ^D End of transmission, not the same as ETB */
+#define KEY_ENQ 5 /**< ^E Enquiry, goes with ACK; old HP flow control */
+#define KEY_ACK 6 /**< ^F Acknowledge, clears ENQ logon hand */
+#define KEY_BEL 7 /**< ^G Bell, rings the bell... */
+#define KEY_BS  8 /**< ^H Backspace, works on HP terminals/computers */
+#define KEY_HT  9 /**< ^I Horizontal tab, move to next tab stop */
+#define KEY_LF  10  /**< ^J Line Feed */
+#define KEY_VT  11  /**< ^K Vertical tab */
+#define KEY_FF  12  /**< ^L Form Feed, page eject */
+#define KEY_CR  13  /**< ^M Carriage Return*/
+#define KEY_SO  14  /**< ^N Shift Out, alternate character set */
+#define KEY_SI  15  /**< ^O Shift In, resume defaultn character set */
+#define KEY_DLE 16  /**< ^P Data link escape */
+#define KEY_DC1 17  /**< ^Q XON, with XOFF to pause listings; "okay to send". */
+#define KEY_DC2 18  /**< ^R Device control 2, block-mode flow control */
+#define KEY_DC3 19  /**< ^S XOFF, with XON is TERM=18 flow control */
+#define KEY_DC4 20  /**< ^T Device control 4 */
+#define KEY_NAK 21  /**< ^U Negative acknowledge */
+#define KEY_SYN 22  /**< ^V Synchronous idle */
+#define KEY_ETB 23  /**< ^W End transmission block, not the same as EOT */
+#define KEY_CAN 24  /**< ^X Cancel line, MPE echoes !!! */
+#define KEY_EM  25  /**< ^Y End of medium, Control-Y interrupt */
+#define KEY_SUB 26  /**< ^Z Substitute */
+#define KEY_ESC 27  /**< ^[ Escape, next character is not echoed */
+#define KEY_FS  28  /**< ^\ File separator */
+#define KEY_GS  29  /**< ^] Group separator */
+#define KEY_RS  30  /**< ^^ Record separator, block-mode terminator */
+#define KEY_US  31  /**< ^_ Unit separator */
+
+#define KEY_DEL 127 /**< Delete (not a real control character...) */
+
+#define IS_CONTROL_CHAR(x) ((x)<=31)
+
+// direction of history navigation
+#define _HIST_UP   0
+#define _HIST_DOWN 1
+// esc seq internal codes
+#define _ESC_BRACKET  1
+#define _ESC_HOME     2
+#define _ESC_END      3
+
+#ifdef _USE_HISTORY
+// history struct, contain internal variable
+// history store in static ring buffer for memory saving
+typedef struct {
+	char ring_buf [_RING_HISTORY_LEN];
+	int begin;
+	int end;
+	int cur;
+} ring_history_t;
+#endif
+
+// microrl struct, contain internal library data
+typedef struct {
+#ifdef _USE_ESC_SEQ
+	char escape_seq;
+	char escape;
+#endif
+#if (defined(_ENDL_CRLF) || defined(_ENDL_LFCR))
+	char tmpch;
+#endif
+#ifdef _USE_HISTORY
+	ring_history_t ring_hist;          // history object
+#endif
+	char * prompt_str;                 // pointer to prompt string
+	char cmdline [_COMMAND_LINE_LEN];  // cmdline buffer
+	int cmdlen;                        // last position in command line
+	int cursor;                        // input cursor
+	int (*execute) (int argc, const char * const * argv );            // ptr to 'execute' callback
+	char ** (*get_completion) (int argc, const char * const * argv ); // ptr to 'completion' callback
+	void (*print) (const char *);                                     // ptr to 'print' callback
+#ifdef _USE_CTLR_C
+	void (*sigint) (void);
+#endif
+} microrl_t;
+
+// init internal data, calls once at start up
+void microrl_init (microrl_t * pThis, void (*print)(const char*));
+
+// set echo mode (true/false), using for disabling echo for password input
+// echo mode will enabled after user press Enter.
+void microrl_set_echo (int);
+
+// set pointer to callback complition func, that called when user press 'Tab'
+// callback func description:
+//   param: argc - argument count, argv - pointer array to token string
+//   must return NULL-terminated string, contain complite variant splitted by 'Whitespace'
+//   If complite token found, it's must contain only one token to be complitted
+//   Empty string if complite not found, and multiple string if there are some token
+void microrl_set_complete_callback (microrl_t * pThis, char ** (*get_completion)(int, const char* const*));
+
+// pointer to callback func, that called when user press 'Enter'
+// execute func param: argc - argument count, argv - pointer array to token string
+void microrl_set_execute_callback (microrl_t * pThis, int (*execute)(int, const char* const*));
+
+// set callback for Ctrl+C terminal signal
+#ifdef _USE_CTLR_C
+void microrl_set_sigint_callback (microrl_t * pThis, void (*sigintf)(void));
+#endif
+
+// insert char to cmdline (for example call in usart RX interrupt)
+void microrl_insert_char (microrl_t * pThis, int ch);
+
+#endif

lib/matejx_avr_lib/README.txt

@@ -0,0 +1,2 @@
+
+Library homepage is at www.randomport.com

lib/matejx_avr_lib/hwdefs.h

@@ -0,0 +1,20 @@
+#ifndef MAT_HWDEFS_H
+#define MAT_HWDEFS_H
+
+#define DDR(x) (*(&x - 1))
+#define PIN(x) (*(&x - 2))
+
+#define MFRC522_SS_PORT     PORTB
+#define MFRC522_SS_BIT      0
+
+#define MFRC522_RST_PORT    PORTL
+#define MFRC522_RST_BIT     0
+
+#define SCK_DDR     DDRB
+#define SCK_BIT     DDB1
+#define MOSI_DDR    DDRB
+#define MOSI_BIT    DDB2
+#define MISO_DDR    DDRB
+#define MISO_BIT    DDB3
+
+#endif

lib/matejx_avr_lib/hwdefs_minimal.h

@@ -0,0 +1,7 @@
+#ifndef MAT_HWDEFS_H
+#define MAT_HWDEFS_H
+
+	#define DDR(x) (*(&x - 1))
+	#define PIN(x) (*(&x - 2))
+
+#endif

lib/matejx_avr_lib/mfrc522.h

@@ -0,0 +1,253 @@
+#ifndef MFRC522_h
+#define MFRC522_h
+
+	#include <inttypes.h>
+
+	typedef uint8_t bool;
+	typedef uint8_t byte;
+	typedef uint16_t word;
+
+	// MFRC522 registers. Described in chapter 9 of the datasheet.
+	// When using SPI all addresses are shifted one bit left in the "SPI address byte" (section 8.1.2.3)
+	enum PCD_Register {
+		// Page 0: Command and status
+		//						  0x00			// reserved for future use
+		CommandReg				= 0x01 << 1,	// starts and stops command execution
+		ComIEnReg				= 0x02 << 1,	// enable and disable interrupt request control bits
+		DivIEnReg				= 0x03 << 1,	// enable and disable interrupt request control bits
+		ComIrqReg				= 0x04 << 1,	// interrupt request bits
+		DivIrqReg				= 0x05 << 1,	// interrupt request bits
+		ErrorReg				= 0x06 << 1,	// error bits showing the error status of the last command executed
+		Status1Reg				= 0x07 << 1,	// communication status bits
+		Status2Reg				= 0x08 << 1,	// receiver and transmitter status bits
+		FIFODataReg				= 0x09 << 1,	// input and output of 64 byte FIFO buffer
+		FIFOLevelReg			= 0x0A << 1,	// number of bytes stored in the FIFO buffer
+		WaterLevelReg			= 0x0B << 1,	// level for FIFO underflow and overflow warning
+		ControlReg				= 0x0C << 1,	// miscellaneous control registers
+		BitFramingReg			= 0x0D << 1,	// adjustments for bit-oriented frames
+		CollReg					= 0x0E << 1,	// bit position of the first bit-collision detected on the RF interface
+		//						  0x0F			// reserved for future use
+
+		// Page 1:Command
+		// 						  0x10			// reserved for future use
+		ModeReg					= 0x11 << 1,	// defines general modes for transmitting and receiving
+		TxModeReg				= 0x12 << 1,	// defines transmission data rate and framing
+		RxModeReg				= 0x13 << 1,	// defines reception data rate and framing
+		TxControlReg			= 0x14 << 1,	// controls the logical behavior of the antenna driver pins TX1 and TX2
+		TxASKReg				= 0x15 << 1,	// controls the setting of the transmission modulation
+		TxSelReg				= 0x16 << 1,	// selects the internal sources for the antenna driver
+		RxSelReg				= 0x17 << 1,	// selects internal receiver settings
+		RxThresholdReg			= 0x18 << 1,	// selects thresholds for the bit decoder
+		DemodReg				= 0x19 << 1,	// defines demodulator settings
+		// 						  0x1A			// reserved for future use
+		// 						  0x1B			// reserved for future use
+		MfTxReg					= 0x1C << 1,	// controls some MIFARE communication transmit parameters
+		MfRxReg					= 0x1D << 1,	// controls some MIFARE communication receive parameters
+		// 						  0x1E			// reserved for future use
+		SerialSpeedReg			= 0x1F << 1,	// selects the speed of the serial UART interface
+
+		// Page 2: Configuration
+		// 						0x20			// reserved for future use
+		CRCResultRegH			= 0x21 << 1,	// shows the MSB and LSB values of the CRC calculation
+		CRCResultRegL			= 0x22 << 1,
+		// 						  0x23			// reserved for future use
+		ModWidthReg				= 0x24 << 1,	// controls the ModWidth setting?
+		// 						  0x25			// reserved for future use
+		RFCfgReg				= 0x26 << 1,	// configures the receiver gain
+		GsNReg					= 0x27 << 1,	// selects the conductance of the antenna driver pins TX1 and TX2 for modulation
+		CWGsPReg				= 0x28 << 1,	// defines the conductance of the p-driver output during periods of no modulation
+		ModGsPReg				= 0x29 << 1,	// defines the conductance of the p-driver output during periods of modulation
+		TModeReg				= 0x2A << 1,	// defines settings for the internal timer
+		TPrescalerReg			= 0x2B << 1,	// the lower 8 bits of the TPrescaler value. The 4 high bits are in TModeReg.
+		TReloadRegH				= 0x2C << 1,	// defines the 16-bit timer reload value
+		TReloadRegL				= 0x2D << 1,
+		TCounterValueRegH		= 0x2E << 1,	// shows the 16-bit timer value
+		TCounterValueRegL		= 0x2F << 1,
+
+		// Page 3:Test Registers
+		// 						  0x30			// reserved for future use
+		TestSel1Reg				= 0x31 << 1,	// general test signal configuration
+		TestSel2Reg				= 0x32 << 1,	// general test signal configuration
+		TestPinEnReg			= 0x33 << 1,	// enables pin output driver on pins D1 to D7
+		TestPinValueReg			= 0x34 << 1,	// defines the values for D1 to D7 when it is used as an I/O bus
+		TestBusReg				= 0x35 << 1,	// shows the status of the internal test bus
+		AutoTestReg				= 0x36 << 1,	// controls the digital self test
+		VersionReg				= 0x37 << 1,	// shows the software version
+		AnalogTestReg			= 0x38 << 1,	// controls the pins AUX1 and AUX2
+		TestDAC1Reg				= 0x39 << 1,	// defines the test value for TestDAC1
+		TestDAC2Reg				= 0x3A << 1,	// defines the test value for TestDAC2
+		TestADCReg				= 0x3B << 1		// shows the value of ADC I and Q channels
+		// 						  0x3C			// reserved for production tests
+		// 						  0x3D			// reserved for production tests
+		// 						  0x3E			// reserved for production tests
+		// 						  0x3F			// reserved for production tests
+	};
+
+	// MFRC522 comands. Described in chapter 10 of the datasheet.
+	enum PCD_Command {
+		PCD_Idle				= 0x00,		// no action, cancels current command execution
+		PCD_Mem					= 0x01,		// stores 25 bytes into the internal buffer
+		PCD_GenerateRandomID	= 0x02,		// generates a 10-byte random ID number
+		PCD_CalcCRC				= 0x03,		// activates the CRC coprocessor or performs a self test
+		PCD_Transmit			= 0x04,		// transmits data from the FIFO buffer
+		PCD_NoCmdChange			= 0x07,		// no command change, can be used to modify the CommandReg register bits without affecting the command, for example, the PowerDown bit
+		PCD_Receive				= 0x08,		// activates the receiver circuits
+		PCD_Transceive 			= 0x0C,		// transmits data from FIFO buffer to antenna and automatically activates the receiver after transmission
+		PCD_MFAuthent 			= 0x0E,		// performs the MIFARE standard authentication as a reader
+		PCD_SoftReset			= 0x0F		// resets the MFRC522
+	};
+
+	// Commands sent to the PICC.
+	enum PICC_Command {
+		// The commands used by the PCD to manage communication with several PICCs (ISO 14443-3, Type A, section 6.4)
+		PICC_CMD_REQA			= 0x26,		// REQuest command, Type A. Invites PICCs in state IDLE to go to READY and prepare for anticollision or selection. 7 bit frame.
+		PICC_CMD_WUPA			= 0x52,		// Wake-UP command, Type A. Invites PICCs in state IDLE and HALT to go to READY(*) and prepare for anticollision or selection. 7 bit frame.
+		PICC_CMD_CT				= 0x88,		// Cascade Tag. Not really a command, but used during anti collision.
+		PICC_CMD_SEL_CL1		= 0x93,		// Anti collision/Select, Cascade Level 1
+		PICC_CMD_SEL_CL2		= 0x95,		// Anti collision/Select, Cascade Level 1
+		PICC_CMD_SEL_CL3		= 0x97,		// Anti collision/Select, Cascade Level 1
+		PICC_CMD_HLTA			= 0x50,		// HaLT command, Type A. Instructs an ACTIVE PICC to go to state HALT.
+		// The commands used for MIFARE Classic (from http://www.nxp.com/documents/data_sheet/MF1S503x.pdf, Section 9)
+		// Use PCD_MFAuthent to authenticate access to a sector, then use these commands to read/write/modify the blocks on the sector.
+		// The read/write commands can also be used for MIFARE Ultralight.
+		PICC_CMD_MF_AUTH_KEY_A	= 0x60,		// Perform authentication with Key A
+		PICC_CMD_MF_AUTH_KEY_B	= 0x61,		// Perform authentication with Key B
+		PICC_CMD_MF_READ		= 0x30,		// Reads one 16 byte block from the authenticated sector of the PICC. Also used for MIFARE Ultralight.
+		PICC_CMD_MF_WRITE		= 0xA0,		// Writes one 16 byte block to the authenticated sector of the PICC. Called "COMPATIBILITY WRITE" for MIFARE Ultralight.
+		PICC_CMD_MF_DECREMENT	= 0xC0,		// Decrements the contents of a block and stores the result in the internal data register.
+		PICC_CMD_MF_INCREMENT	= 0xC1,		// Increments the contents of a block and stores the result in the internal data register.
+		PICC_CMD_MF_RESTORE		= 0xC2,		// Reads the contents of a block into the internal data register.
+		PICC_CMD_MF_TRANSFER	= 0xB0,		// Writes the contents of the internal data register to a block.
+		// The commands used for MIFARE Ultralight (from http://www.nxp.com/documents/data_sheet/MF0ICU1.pdf, Section 8.6)
+		// The PICC_CMD_MF_READ and PICC_CMD_MF_WRITE can also be used for MIFARE Ultralight.
+		PICC_CMD_UL_WRITE		= 0xA2		// Writes one 4 byte page to the PICC.
+	};
+
+	// MIFARE constants that does not fit anywhere else
+	enum MIFARE_Misc {
+		MF_ACK					= 0xA,		// The MIFARE Classic uses a 4 bit ACK/NAK. Any other value than 0xA is NAK.
+		MF_KEY_SIZE				= 6			// A Mifare Crypto1 key is 6 bytes.
+	};
+
+	// PICC types we can detect. Remember to update PICC_GetTypeName() if you add more.
+	enum PICC_Type {
+		PICC_TYPE_UNKNOWN		= 0,
+		PICC_TYPE_ISO_14443_4	= 1,	// PICC compliant with ISO/IEC 14443-4
+		PICC_TYPE_ISO_18092		= 2, 	// PICC compliant with ISO/IEC 18092 (NFC)
+		PICC_TYPE_MIFARE_MINI	= 3,	// MIFARE Classic protocol, 320 bytes
+		PICC_TYPE_MIFARE_1K		= 4,	// MIFARE Classic protocol, 1KB
+		PICC_TYPE_MIFARE_4K		= 5,	// MIFARE Classic protocol, 4KB
+		PICC_TYPE_MIFARE_UL		= 6,	// MIFARE Ultralight or Ultralight C
+		PICC_TYPE_MIFARE_PLUS	= 7,	// MIFARE Plus
+		PICC_TYPE_TNP3XXX		= 8,	// Only mentioned in NXP AN 10833 MIFARE Type Identification Procedure
+		PICC_TYPE_NOT_COMPLETE	= 255	// SAK indicates UID is not complete.
+	};
+
+	// Return codes from the functions in this class. Remember to update GetStatusCodeName() if you add more.
+	enum StatusCode {
+		STATUS_OK				= 1,	// Success
+		STATUS_ERROR			= 2,	// Error in communication
+		STATUS_COLLISION		= 3,	// Collission detected
+		STATUS_TIMEOUT			= 4,	// Timeout in communication.
+		STATUS_NO_ROOM			= 5,	// A buffer is not big enough.
+		STATUS_INTERNAL_ERROR	= 6,	// Internal error in the code. Should not happen ;-)
+		STATUS_INVALID			= 7,	// Invalid argument.
+		STATUS_CRC_WRONG		= 8,	// The CRC_A does not match
+		STATUS_MIFARE_NACK		= 9		// A MIFARE PICC responded with NAK.
+	};
+
+	// A struct used for passing the UID of a PICC.
+	typedef struct {
+		byte		size;			// Number of bytes in the UID. 4, 7 or 10.
+		byte		uidByte[10];
+		byte		sak;			// The SAK (Select acknowledge) byte returned from the PICC after successful selection.
+	} Uid;
+
+	// A struct used for passing a MIFARE Crypto1 key
+	typedef struct {
+		byte		keyByte[MF_KEY_SIZE];
+	} MIFARE_Key;
+
+	// Member variables
+	//Uid uid;								// Used by PICC_ReadCardSerial().
+
+	// Size of the MFRC522 FIFO
+	//static const byte FIFO_SIZE = 64;		// The FIFO is 64 bytes.
+
+	//-----------------------------------------------------------------------------------
+	// Functions for setting up the Arduino
+	//-----------------------------------------------------------------------------------
+	void MFRC522_init(void);
+	void setSPIConfig(void);
+
+	//-----------------------------------------------------------------------------------
+	// Basic interface functions for communicating with the MFRC522
+	//-----------------------------------------------------------------------------------
+	void PCD_WriteRegister(byte reg, byte value);
+	void PCD_WriteRegister2(byte reg, byte count, byte *values);
+	byte PCD_ReadRegister(byte reg);
+	void PCD_ReadRegister2(byte reg, byte count, byte *values, byte rxAlign);
+	void setBitMask(unsigned char reg, unsigned char mask);
+	void PCD_SetRegisterBitMask(byte reg, byte mask);
+	void PCD_ClearRegisterBitMask(byte reg, byte mask);
+	byte PCD_CalculateCRC(byte *data, byte length, byte *result);
+
+	//-----------------------------------------------------------------------------------
+	// Functions for manipulating the MFRC522
+	//-----------------------------------------------------------------------------------
+	byte PCD_Init(void);
+	byte PCD_Reset(void);
+	void PCD_AntennaOn(void);
+
+	//-----------------------------------------------------------------------------------
+	// Functions for communicating with PICCs
+	//-----------------------------------------------------------------------------------
+	byte PCD_TransceiveData(byte *sendData, byte sendLen, byte *backData, byte *backLen, byte *validBits, byte rxAlign, bool checkCRC);
+	byte PCD_CommunicateWithPICC(byte command, byte waitIRq, byte *sendData, byte sendLen, byte *backData, byte *backLen, byte *validBits, byte rxAlign, bool checkCRC);
+
+	byte PICC_RequestA(byte *bufferATQA, byte *bufferSize);
+	byte PICC_WakeupA(byte *bufferATQA, byte *bufferSize);
+	byte PICC_REQA_or_WUPA(	byte command, byte *bufferATQA, byte *bufferSize);
+	byte PICC_Select(Uid *uid, byte validBits);
+	byte PICC_HaltA(void);
+
+	//-----------------------------------------------------------------------------------
+	// Functions for communicating with MIFARE PICCs
+	//-----------------------------------------------------------------------------------
+	byte PCD_Authenticate(byte command, byte blockAddr, MIFARE_Key *key, Uid *uid);
+	void PCD_StopCrypto1(void);
+	byte MIFARE_Read(byte blockAddr, byte *buffer, byte *bufferSize);
+	byte MIFARE_Write(byte blockAddr, byte *buffer, byte bufferSize);
+ 	byte MIFARE_Decrement(byte blockAddr, long delta);
+	byte MIFARE_Increment(byte blockAddr, long delta);
+ 	byte MIFARE_Restore(byte blockAddr);
+ 	byte MIFARE_Transfer(byte blockAddr);
+	byte MIFARE_Ultralight_Write(byte page, byte *buffer, byte bufferSize);
+
+	//-----------------------------------------------------------------------------------
+	// Support functions
+	//-----------------------------------------------------------------------------------
+	byte PCD_MIFARE_Transceive(	byte *sendData, byte sendLen, bool acceptTimeout);
+	const char *GetStatusCodeName(byte code);
+	byte PICC_GetType(byte sak);
+	const char *PICC_GetTypeName(byte type);
+	void PICC_DumpToSerial(Uid *uid);
+	void PICC_DumpMifareClassicToSerial(Uid *uid, byte piccType, MIFARE_Key *key);
+	void PICC_DumpMifareClassicSectorToSerial(Uid *uid, MIFARE_Key *key, byte sector);
+	void PICC_DumpMifareUltralightToSerial(void);
+	void MIFARE_SetAccessBits(byte *accessBitBuffer, byte g0, byte g1, byte g2, byte g3);
+
+	//-----------------------------------------------------------------------------------
+	// Convenience functions - does not add extra functionality
+	//-----------------------------------------------------------------------------------
+	bool PICC_IsNewCardPresent(void);
+	bool PICC_ReadCardSerial(Uid* uid);
+
+/*
+private:
+	byte _chipSelectPin;		// Arduino pin connected to MFRC522's SPI slave select input (Pin 24, NSS, active low)
+	byte _resetPowerDownPin;	// Arduino pin connected to MFRC522's reset and power down input (Pin 6, NRSTPD, active low)
+	byte MIFARE_TwoStepHelper(byte command, byte blockAddr,	long data);
+*/
+
+#endif

lib/matejx_avr_lib/spi.c

@@ -0,0 +1,98 @@
+/**
+
+SPI methods are not interrupt driven - they wait until SPI operation completes.
+If you're using CMT and would prefer switching to another task while SPI operation
+is in progress, you can define SPI_USE_CMT in swdefs.h. This requires CMT_MUTEX_FUNC.
+
+Also, SS (CS) is not controlled by these methods. It's the responsibility of the user.
+
+@file		spi.c
+@brief		SPI routines
+@author		Matej Kogovsek (matej@hamradio.si)
+@copyright	LGPL 2.1
+@note		This file is part of mat-stm32f1-lib
+*/
+
+#include <inttypes.h>
+#include <avr/io.h>
+#include <avr/interrupt.h>
+
+#include "spi.h"
+#include "hwdefs.h"
+
+#ifdef SPI_USE_CMT
+	#warning SPI using cmt
+	#include "cmt.h"
+	struct cmt_mutex spi_mutex;
+#endif
+
+#ifndef SPCR0
+	#define SPCR0 SPCR
+	#define SPE0 SPE
+	#define MSTR0 MSTR
+	#define SPSR0 SPSR
+	#define SPDR0 SPDR
+	#define SPIF0 SPIF
+#endif
+
+/**
+@brief Initialize SPI interface.
+
+Although SPI can have different clock phase and polarity, I have never ran across anything that uses other
+than low polarity and 1st edge phase. Therefore these parameters are implied and not variable. As are 8 bit
+words and MSB first.
+@param[in]	fdiv		Baudrate prescaler, F_CPU dependent
+*/
+void spi_init(uint8_t fdiv)
+{
+	if( SPCR0 & _BV(SPE0) ) return;
+
+	#ifdef SPI_USE_CMT
+	spi_mutex.ac = 0;
+	#endif
+
+	// make SCK, MOSI pins outputs and MISO an input
+	SCK_DDR |= _BV(SCK_BIT);
+	MOSI_DDR |= _BV(MOSI_BIT);
+	MISO_DDR &= ~_BV(MISO_BIT);
+
+	// init SPI, MSB first, SCK low when idle
+	SPCR0 = _BV(SPE0) | _BV(MSTR0) | (fdiv & 3);
+	SPSR0 = (fdiv >> 2) & 1;
+}
+
+/**
+@brief Send and receive byte (NSS not controlled)
+@param[in]	d			Byte to send
+@return byte received
+*/
+uint8_t spi_rw(uint8_t d)
+{
+	#ifdef SPI_USE_CMT
+	cmt_acquire(&spi_mutex);
+	#endif
+
+	SPCR0 |= _BV(MSTR0);
+	SPDR0 = d;
+	while( !(SPSR0 & _BV(SPIF0)) ) {
+		#ifdef SPI_USE_CMT
+		cmt_delay_ticks(0);
+		#endif
+	}
+	d = SPDR0;
+
+	#ifdef SPI_USE_CMT
+	cmt_release(&spi_mutex);
+	#endif
+
+	return d;
+}
+
+// ------------------------------------------------------------------
+// INTERRUPTS
+// ------------------------------------------------------------------
+
+ISR(SPI_STC_vect)
+{
+//
+}

lib/matejx_avr_lib/spi.h

@@ -0,0 +1,13 @@
+#ifndef MAT_SPI_H
+#define MAT_SPI_H
+
+#include <inttypes.h>
+#include <avr/io.h>
+
+// init SPI
+void spi_init(uint8_t fdiv);
+
+// send a byte over SPI
+uint8_t spi_rw(uint8_t d);
+
+#endif

src/cli_microrl.c

@@ -0,0 +1,227 @@
+/*   Copyright (C) 2016 Arti Zirk <arti.zirk@gmail.com>
+ *
+ *   This file is part of I237 Door Access program.
+ *
+ *   I237 Door Access 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   I237 Door Access 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 I237 Door Access.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <avr/pgmspace.h>
+#include "../lib/hd44780_111/hd44780.h"
+#include "../lib/andygock_avr-uart/uart.h"
+#include "hmi_msg.h"
+#include "print_helper.h"
+#include "cli_microrl.h"
+#include "../lib/matejx_avr_lib/mfrc522.h"
+#include "rfid.h"
+
+
+typedef struct cli_cmd {
+    PGM_P cmd;
+    PGM_P help;
+    void (*func_p)();
+    const uint8_t func_argc;
+} cli_cmd_t;
+
+
+const cli_cmd_t cli_cmds[] = {
+    {help_cmd, help_help, cli_print_help, 0},
+    {ver_cmd, ver_help, cli_print_ver, 0},
+    {ascii_cmd, ascii_help, cli_print_ascii_tbls, 0},
+    {month_cmd, month_help, cli_handle_month, 1},
+    {read_cmd, read_help, cli_rfid_read, 0},
+    {add_cmd, add_help, cli_rfid_add, 1},
+    {remove_cmd, remove_help, cli_rfid_remove, 1},
+    {list_cmd, list_help, cli_rfid_list, 0}
+};
+
+
+void cli_print(const char *str)
+{
+    printf("%s", str);
+}
+
+
+char cli_get_char(void)
+{
+    if (uart0_peek() != UART_NO_DATA) {
+        return uart0_getc() & UART_STATUS_MASK;
+    } else {
+        return 0x00;
+    }
+}
+
+
+void cli_print_help(const char *const *argv)
+{
+    (void) argv;
+    printf_P(PSTR(CLI_HELP_MSG "\n"));
+
+    for (uint8_t i = 0; i < NUM_ELEMS(cli_cmds); i++) {
+        printf_P(cli_cmds[i].cmd);
+        printf_P(PSTR(" : "));
+        printf_P(cli_cmds[i].help);
+        putc('\n', stdout);
+    }
+}
+
+
+void print_version(FILE *stream)
+{
+    // Print program and libc versions
+    fprintf_P(stream, PSTR(PROG_VERSION "\n"),
+              PSTR(GIT_DESCR), PSTR(__DATE__), PSTR(__TIME__));
+    fprintf_P(stream, PSTR(LIBC_VERSION "\n"),
+              PSTR(__AVR_LIBC_VERSION_STRING__),
+              PSTR(__VERSION__));
+}
+
+
+void cli_print_ver(const char *const *argv)
+{
+    (void) argv;
+    print_version(stdout);
+}
+
+
+void cli_print_ascii_tbls(const char *const *argv)
+{
+    (void) argv;
+    // ASCII table print
+    print_ascii_tbl(stdout);
+    unsigned char ascii[128];
+    for (unsigned char i = 0; i < sizeof(ascii); i++) {
+        ascii[i] = i;
+    }
+    print_for_human(stdout, ascii, sizeof(ascii));
+}
+
+
+void cli_handle_month(const char *const *argv)
+{
+    lcd_goto(0x40); // Got to the beginning of the next line
+    char spaces_to_print = 16;
+    for (int i = 0; i < 6; i++) {
+        if (!strncmp_P(argv[1],
+                       (PGM_P)pgm_read_word(&months[i]),
+                       strlen(argv[1]))) {
+            char printed_count;
+            printed_count = fprintf_P(stdout, (PGM_P)pgm_read_word(&months[i]));
+            fputc('\n', stdout);
+            lcd_puts_P((PGM_P)pgm_read_word(&months[i]));
+            lcd_putc(' ');
+            spaces_to_print -= (printed_count + 1);
+        }
+    }
+    // Clear the end of the line
+    for (; spaces_to_print > -1; spaces_to_print--) {
+        lcd_putc(' ');
+    }
+}
+
+
+void cli_rfid_read(const char *const *argv)
+{
+    (void) argv;
+    Uid uid;
+    Uid *uid_ptr = &uid;
+    if (PICC_IsNewCardPresent()) {
+        printf(CARD_SELECTED_MSG "\n");
+        PICC_ReadCardSerial(uid_ptr);
+        printf_P(PSTR(UID_SIZE_MSG "\n"), uid.size);
+        printf_P(PSTR(UID_SAK_MSG"\n"), uid.sak);
+        printf_P(PSTR(CARD_UID_MSG));
+        for (byte i = 0; i < uid.size; i++) {
+            printf("%02X", uid.uidByte[i]);
+        }
+        putc('\n', stdout);
+    } else {
+        printf_P((PSTR(CARD_NOT_SELECTED)));
+    }
+}
+
+
+void cli_rfid_add(const char *const *argv)
+{
+    (void) argv;
+    Uid uid;
+    card_t card;
+    if (PICC_IsNewCardPresent()) {
+        PICC_ReadCardSerial(&uid);
+        card.uid_size = uid.size;
+        memcpy(&card.uid, &uid.uidByte, uid.size);
+        char *user = malloc(strlen(argv[1]) + 1);
+        if(!user) {
+            printf_P(PSTR(OUT_OF_MEMORY_MSG "\n"));
+            return;
+        }
+        strcpy(user, argv[1]);
+        card.user = user;
+        rfid_add_card(&card);
+        free(user); // card user has ben copied to the linked list
+    } else {
+        printf_P(PSTR(UNABLE_TO_DETECT_CARD_MSG "\n"));
+    }
+}
+
+
+void cli_rfid_remove(const char *const *argv)
+{
+    (void) argv;
+    rfid_remove_card_by_user(argv[1]);
+}
+
+
+void cli_rfid_list(const char *const *argv)
+{
+    (void) argv;
+    rfid_list_cards();
+}
+
+
+void cli_print_cmd_error(void)
+{
+    printf_P(PSTR(CLI_NO_CMD "\n"));
+}
+
+
+void cli_print_cmd_arg_error(void)
+{
+    printf_P(PSTR(CLI_ARGS_MSG "\n"));
+}
+
+
+int cli_execute(int argc, const char *const *argv)
+{
+    for (uint8_t i = 0; i < NUM_ELEMS(cli_cmds); i++) {
+        if (!strcmp_P(argv[0], cli_cmds[i].cmd)) {
+            putc('\n', stdout);
+            // Test do we have correct arguments to run command
+            // Function arguments count shall be defined in struct
+            if ((argc - 1) != cli_cmds[i].func_argc) {
+                cli_print_cmd_arg_error();
+                return 0;
+            }
+
+            // Hand argv over to function pointer,
+            // cross fingers and hope that funcion handles it properly
+            cli_cmds[i].func_p (argv);
+            return 0;
+        }
+    }
+    putc('\n', stdout);
+    cli_print_cmd_error();
+    return 0;
+}

src/cli_microrl.h

@@ -0,0 +1,41 @@
+/*   Copyright (C) 2016 Arti Zirk <arti.zirk@gmail.com>
+ *
+ *   This file is part of I237 Door Access program.
+ *
+ *   I237 Door Access 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   I237 Door Access 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 I237 Door Access.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef _CLI_MICRORL_H_
+#define _CLI_MICRORL_H_
+
+#define NUM_ELEMS(x)        (sizeof(x) / sizeof((x)[0]))
+#define UART_STATUS_MASK    0x00FF
+
+
+void cli_print(const char * str);
+char cli_get_char(void);
+void cli_print_help(const char *const *argv);
+void print_version(FILE *stream);
+void cli_print_ver(const char *const *argv);
+void cli_print_ascii_tbls(const char *const *argv);
+void cli_handle_month(const char *const *argv);
+void cli_rfid_read(const char *const *argv);
+void cli_rfid_add(const char *const *argv);
+void cli_rfid_remove(const char *const *argv);
+void cli_rfid_list(const char *const *argv);
+void cli_print_cmd_error(void);
+void cli_print_cmd_arg_error(void);
+int cli_execute(int argc, const char *const *argv);
+
+
+#endif /* _CLI_MICRORL_H_ */

src/hmi_msg.c

@@ -0,0 +1,47 @@
+/*   Copyright (C) 2016 Arti Zirk <arti.zirk@gmail.com>
+ *
+ *   This file is part of I237 Door Access program.
+ *
+ *   I237 Door Access 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   I237 Door Access 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 I237 Door Access.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <avr/pgmspace.h>
+#include "hmi_msg.h"
+
+
+static const char m1[] PROGMEM = "January";
+static const char m2[] PROGMEM = "February";
+static const char m3[] PROGMEM = "March";
+static const char m4[] PROGMEM = "April";
+static const char m5[] PROGMEM = "May";
+static const char m6[] PROGMEM = "June";
+
+PGM_P const months[] PROGMEM = {m1, m2, m3, m4, m5, m6};
+
+const char help_cmd[] PROGMEM = HELP_CMD;
+const char help_help[] PROGMEM = HELP_HELP;
+const char ver_cmd[] PROGMEM = VER_CMD;
+const char ver_help[] PROGMEM = VER_HELP;
+const char ascii_cmd[] PROGMEM = ASCII_CMD;
+const char ascii_help[] PROGMEM = ASCII_HELP;
+const char month_cmd[] PROGMEM = MONTH_CMD;
+const char month_help[] PROGMEM = MONTH_HELP;
+const char read_cmd[] PROGMEM = READ_CMD;
+const char read_help[] PROGMEM = READ_HELP;
+const char add_cmd[] PROGMEM = ADD_CMD;
+const char add_help[] PROGMEM = ADD_HELP;
+const char remove_cmd[] PROGMEM = REMOVE_CMD;
+const char remove_help[] PROGMEM = REMOVE_HELP;
+const char list_cmd[] PROGMEM = LIST_CMD;
+const char list_help[] PROGMEM = LIST_HELP;
+const char access_denied_msg[] PROGMEM = ACCESS_DENIED_MSG;

src/hmi_msg.h

@@ -1,19 +1,92 @@
-#include <avr/pgmspace.h>
+/*   Copyright (C) 2016 Arti Zirk <arti.zirk@gmail.com>
+ *
+ *   This file is part of I237 Door Access program.
+ *
+ *   I237 Door Access 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   I237 Door Access 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 I237 Door Access.  If not, see <http://www.gnu.org/licenses/>.
+ */
 #ifndef _HMI_MSG_H_
 #define _HMI_MSG_H_
 
+
 #define PROG_VERSION "Version: %S built on: %S %S"
-#define LIBC_VERSION "avr-libc version: %S"
+#define LIBC_VERSION "avr-libc version: %S avr-gcc version: %S"
 #define STUD_NAME "Arti Zirk"
 #define GET_MONTH_MSG "Enter Month name first letter >"
 #define UPTIME_MSG "Uptime: %lu s"
 
-const char m1[] PROGMEM = "January";
-const char m2[] PROGMEM = "February";
-const char m3[] PROGMEM = "March";
-const char m4[] PROGMEM = "April";
-const char m5[] PROGMEM = "May";
-const char m6[] PROGMEM = "June";
+#define CLI_HELP_MSG "Implemented commands:"
+#define CLI_NO_CMD "Command not implemented.\n Use <help> to get help."
+#define CLI_ARGS_MSG "To few or to many arguments for this command\nUse <help>"
+
+#define HELP_CMD "help"
+#define HELP_HELP "Get help"
+
+#define VER_CMD "version"
+#define VER_HELP "Print FW version"
+
+#define ASCII_CMD "ascii"
+#define ASCII_HELP "print ASCII tables"
+
+#define MONTH_CMD "month"
+#define MONTH_HELP "Find matching month from lookup list. Usage: month <string>"
+
+#define READ_CMD "read"
+#define READ_HELP "Read and print out card info that is currently in proximity of the reader"
+
+#define ADD_CMD "add"
+#define ADD_HELP "Add a new card to the system. Usage: add <username>"
+
+#define REMOVE_CMD "remove"
+#define REMOVE_HELP "Remove a card from the system. Usage: remove <username>"
+
+#define LIST_CMD "list"
+#define LIST_HELP "List all added cards"
+
+#define ACCESS_DENIED_MSG "Access denied!"
+#define NOT_ADDING_CARD_MSG1 "Found card \""
+#define NOT_ADDING_CARD_MSG2 "\", not adding it again."
+#define OUT_OF_MEMORY_MSG "Out of memory. Please remove cards."
+#define NO_CARDS_ADDED_MSG "No cards added"
+#define CARD_NOT_FOUND_MSG "Card not found"
+#define LINKED_LIST_ERROR_MSG "Invalid situation when removing card"
+#define UNABLE_TO_DETECT_CARD_MSG "Unable to detect card."
+#define CARD_SELECTED_MSG "Card selected!"
+#define UID_SIZE_MSG "UID size: 0x%02X"
+#define UID_SAK_MSG "UID sak: 0x%02X"
+#define CARD_UID_MSG "Card UID: "
+#define CARD_NOT_SELECTED "Unable to select card.\n"
+
+
+extern PGM_P const months[];
+
+extern const char help_cmd[];
+extern const char help_help[];
+extern const char ver_cmd[];
+extern const char ver_help[];
+extern const char ascii_cmd[];
+extern const char ascii_help[];
+extern const char month_cmd[];
+extern const char month_help[];
+extern const char read_cmd[];
+extern const char read_help[];
+extern const char add_cmd[];
+extern const char add_help[];
+extern const char remove_cmd[];
+extern const char remove_help[];
+extern const char list_cmd[];
+extern const char list_help[];
+extern const char access_denied_msg[];
+
 
-PGM_P const months[] PROGMEM = {m1,m2,m3,m4,m5,m6};
 #endif /* _HMI_MSG_H_ */

src/main.c

@@ -1,6 +1,23 @@
+/*   Copyright (C) 2016 Arti Zirk <arti.zirk@gmail.com>
+ *
+ *   This file is part of I237 Door Access program.
+ *
+ *   I237 Door Access 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   I237 Door Access 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 I237 Door Access.  If not, see <http://www.gnu.org/licenses/>.
+ */
 #include <stdio.h>
 #include <string.h>
-#include <time.h>
+#include <util/atomic.h>
 #include <avr/io.h>
 #include <avr/interrupt.h>
 #include <avr/pgmspace.h>
@@ -10,12 +27,30 @@
 #include "uart_wrap.h"
 #include "print_helper.h"
 #include "../lib/hd44780_111/hd44780.h"
+#include "../lib/helius_microrl/microrl.h"
+#include "cli_microrl.h"
+#include "../lib/matejx_avr_lib/mfrc522.h"
+#include "rfid.h"
 
+
+// uart0 and uart3 will run at this speed
 #define BAUDRATE 9600
 
 // For configuring arduino mega pin 25
-#define LED_INIT DDRA |= _BV(DDA3);
+#define LED_INIT DDRA |= _BV(DDA3)
+#define DOOR_INIT DDRA |= _BV(DDA1)
 #define LED_TOGGLE PORTA ^= _BV(PORTA3)
+#define DOOR_OPEN PORTA |= _BV(PORTA1)
+#define DOOR_CLOSE PORTA &= ~_BV(PORTA1)
+#define UART_STATUS_MASK    0x00FF
+
+// Current system time
+volatile uint32_t system_time;
+
+// Create microrl object and pointer on it
+static microrl_t rl;
+static microrl_t *prl = &rl;
+
 
 static inline void init_system_clock(void)
 {
@@ -26,12 +61,33 @@ static inline void init_system_clock(void)
     TIMSK5 |= _BV(OCIE5A); // Output Compare A Match Interrupt Enable
 }
 
+
+static inline uint32_t time(void)
+{
+    uint32_t cur_time;
+    ATOMIC_BLOCK(ATOMIC_FORCEON) {
+        cur_time = system_time;
+    }
+    return cur_time;
+}
+
+
+static inline void init_rfid_reader(void)
+{
+    MFRC522_init();
+    PCD_Init();
+}
+
+
 static inline void init_hw (void)
 {
     // IO init
-    /// Set arduino pin 25 as output
+    // Set arduino pin 25 as output
     LED_INIT;
 
+    // Set Arduino pin 23 as output
+    DOOR_INIT;
+
     // System clock
     init_system_clock();
 
@@ -45,61 +101,38 @@ static inline void init_hw (void)
     lcd_init();
     lcd_clrscr();
 
+    // Init RFID-RC522
+    init_rfid_reader();
+
     // Enable interupts
     sei();
 }
 
+
 static inline void start_ui (void)
 {
-    // Print program and libc versions
-    fprintf_P(stderr, PSTR(PROG_VERSION "\n"),
-              PSTR(GIT_DESCR), PSTR(__DATE__), PSTR(__TIME__));
-    fprintf_P(stderr, PSTR(LIBC_VERSION "\n"), PSTR(__AVR_LIBC_VERSION_STRING__));
+    print_version(stderr);
 
     // print student name
     fprintf_P(stdout, PSTR(STUD_NAME));
     fputc('\n', stdout); // Add a new line to the uart printout
     lcd_puts_P(PSTR(STUD_NAME));
-
-    // ASCII table print
-    print_ascii_tbl(stdout);
-    unsigned char ascii[128];
-    for (unsigned char i = 0; i < sizeof(ascii); i++) {
-        ascii[i] = i;
-    }
-    print_for_human(stdout, ascii, sizeof(ascii));
-
-    // Bootstrap search_month message
-    fprintf_P(stdout, PSTR(GET_MONTH_MSG));
 }
 
-static inline void search_month (void)
+
+static inline void start_cli(void)
 {
-    char letter;
-
-    fscanf(stdin, "%c", &letter);
-    fprintf(stdout, "%c\n", letter);
-    lcd_goto(0x40); // Got to the beginning of the next line
-    for (int i = 0; i < 6; i++) {
-        if (!strncmp_P(&letter, (PGM_P)pgm_read_word(&months[i]), 1)) {
-            fprintf_P(stdout, (PGM_P)pgm_read_word(&months[i]));
-            fputc('\n', stdout);
-            lcd_puts_P((PGM_P)pgm_read_word(&months[i]));
-            lcd_putc(' ');
-        }
-    }
-
-    // this is fine because even when the hd44780 address counter goes over 0xf4
-    // we still have quite a few addresses left until address counter overflow
-    // and we also dont care about the data that is at the end of the ddram
-    lcd_puts_P(PSTR("                ")); // Clear the end of the line
-    fprintf_P(stdout, PSTR(GET_MONTH_MSG));
+    // Call init with ptr to microrl instance and print callback
+    microrl_init (prl, cli_print);
+    // Set callback for execute
+    microrl_set_execute_callback (prl, cli_execute);
 }
 
+
 static inline void heartbeat (void)
 {
-    static time_t time_prev;
-    time_t time_cur = time(NULL);
+    static uint32_t time_prev;
+    uint32_t time_cur = time();
     if (time_cur <= time_prev) {
         return;
     }
@@ -108,21 +141,72 @@ static inline void heartbeat (void)
     LED_TOGGLE;
 }
 
+
+static inline void handle_door()
+{
+    Uid uid;
+    card_t card;
+    uint32_t time_cur = time();
+    static uint32_t message_start;
+    static uint32_t door_open_start;
+    if (PICC_IsNewCardPresent()) {
+        PICC_ReadCardSerial(&uid);
+        card.uid_size = uid.size;
+        memcpy(&card.uid, &uid.uidByte, uid.size);
+        card.user = NULL;
+        card_t *found_card = rfid_find_card(&card);
+        if (found_card) {
+            lcd_goto(0x40);
+            lcd_puts(found_card->user);
+            for (int8_t i = 16 - strlen(found_card->user); i > -1; i--) {
+                lcd_putc(' ');
+            }
+            DOOR_OPEN;
+        } else {
+            DOOR_CLOSE;
+            lcd_goto(0x40);
+            lcd_puts_P(access_denied_msg);
+            for (int8_t i = 16 - strlen_P(access_denied_msg); i > -1; i--) {
+                lcd_putc(' ');
+            }
+        }
+        door_open_start = time_cur;
+        message_start = time_cur;
+    }
+
+    if ((message_start + 5) < time_cur) {
+        // clean the screen once again in 10 secconds so that cli command
+        // `month` could show found months for some time
+        message_start = time_cur + 5;
+        lcd_goto(0x40);
+        for (int8_t i = 16; i > -1; i--) {
+            lcd_putc(' ');
+        }
+    }
+
+    if ((door_open_start + 2) < time_cur) {
+        DOOR_CLOSE;
+    }
+}
+
+
 int main (void)
 {
     init_hw();
     start_ui();
+    start_cli();
 
     while (1) {
         heartbeat();
-        if (uart0_available()) {
-            search_month();
-        }
+        // CLI commands are handled in cli_execute()
+        microrl_insert_char (prl, cli_get_char());
+        handle_door();
     }
 }
 
+
 // System clock
 ISR(TIMER5_COMPA_vect)
 {
-    system_tick();
+    system_time++;
 }

src/print_helper.c

@@ -1,7 +1,25 @@
+/*   Copyright (C) 2016 Arti Zirk <arti.zirk@gmail.com>
+ *
+ *   This file is part of I237 Door Access program.
+ *
+ *   I237 Door Access 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   I237 Door Access 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 I237 Door Access.  If not, see <http://www.gnu.org/licenses/>.
+ */
 #include <stdio.h>
 #include <avr/pgmspace.h>
 #include "print_helper.h"
 
+
 int print_ascii_tbl (FILE *stream)
 {
     for (char c = ' '; c <= '~'; c++) {

src/print_helper.h

@@ -1,3 +1,20 @@
+/*   Copyright (C) 2016 Arti Zirk <arti.zirk@gmail.com>
+ *
+ *   This file is part of I237 Door Access program.
+ *
+ *   I237 Door Access 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   I237 Door Access 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 I237 Door Access.  If not, see <http://www.gnu.org/licenses/>.
+ */
 #ifndef _PRINT_HELPER_H_
 #define _PRINT_HELPER_H_
 

src/rfid.c

@@ -0,0 +1,165 @@
+/*   Copyright (C) 2016 Arti Zirk <arti.zirk@gmail.com>
+ *
+ *   This file is part of I237 Door Access program.
+ *
+ *   I237 Door Access 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   I237 Door Access 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 I237 Door Access.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <avr/pgmspace.h>
+#include "rfid.h"
+#include "hmi_msg.h"
+
+
+card_t *head = NULL;
+
+
+void rfid_print_card(const card_t *card)
+{
+    for (uint8_t i = 0; i < card->uid_size; i++) {
+        printf("%02X", card->uid[i]);
+    }
+    printf(": %s", card->user);
+}
+
+
+card_t* rfid_find_card(const card_t *card)
+{
+    if (head != NULL) {
+        card_t *current;
+        current = head;
+        while (current != NULL) {
+            if ((current->uid_size != card->uid_size) ||
+                    !memcmp(current->uid, card->uid, current->uid_size) ||
+                    ((card->user != NULL) && !strcmp(current->user, card->user))) {
+
+                return current;
+            }
+            current = current->next;
+        }
+    }
+    return NULL;
+}
+
+
+void rfid_add_card(const card_t *card)
+{
+    card_t *found_card = rfid_find_card(card);
+    if (found_card) {
+        printf_P(PSTR(NOT_ADDING_CARD_MSG1));
+        rfid_print_card(found_card);
+        printf_P(PSTR(NOT_ADDING_CARD_MSG2 "\n"));
+        return;
+    }
+
+    // Card doesn't exist, add it
+    card_t *new_card;
+    char *new_card_user;
+    new_card = malloc(sizeof(card_t));
+    new_card_user = malloc(strlen(card->user) + 1);
+    if (!new_card || !new_card_user) {
+        printf_P(PSTR(OUT_OF_MEMORY_MSG "\n"));
+        free(new_card_user);
+        free(new_card);
+        return;
+    }
+
+    // Copy card data
+    new_card->uid_size = card->uid_size;
+    memcpy(new_card->uid, card->uid, card->uid_size);
+    strcpy(new_card_user, card->user);
+    new_card->user = new_card_user;
+    new_card->next = NULL;
+
+    // Update card list
+    if (head == NULL) {
+        head = new_card;
+    } else {
+        card_t *current;
+        current = head;
+        while (current->next != NULL) {
+            current = current->next;
+        }
+        current->next = new_card;
+    }
+    return;
+}
+
+
+void rfid_list_cards(void)
+{
+    if (head == NULL) {
+        printf_P(PSTR(NO_CARDS_ADDED_MSG "\n"));
+    } else {
+        card_t *current;
+        current = head;
+        while (current->next != NULL) {
+            rfid_print_card(current);
+            putc('\n', stdout);
+            current = current->next;
+        }
+        rfid_print_card(current);
+        putc('\n', stdout);
+    }
+}
+
+
+void rfid_remove_card_by_user(const char *user)
+{
+    card_t *curr;
+    card_t *prev;
+    curr = head;
+    prev = NULL;
+    if (head == NULL) {
+        printf_P(PSTR(NO_CARDS_ADDED_MSG "\n"));
+        return;
+    } else {
+        while (curr->next != NULL) {
+            if (strcmp(curr->user, user) == 0) {
+                break;
+            }
+            prev = curr;
+            curr = curr->next;
+        }
+    }
+    if (strcmp(curr->user, user) == 0) {
+        if (prev == NULL && curr->next == NULL) {
+            // this is the single card in the list
+            free(curr->user);
+            free(curr);
+            head = NULL;
+        } else if (prev == NULL && curr->next != NULL) {
+            // this is the first card in the list, with more after it
+            head = curr->next;
+            free(curr->user);
+            free(curr);
+        } else if (prev != NULL && curr->next != NULL) {
+            // this card is somewhere in the middle of the list
+            prev->next = curr->next;
+            free(curr->user);
+            free(curr);
+        } else if (prev != NULL && curr->next == NULL) {
+            // this is the last card in the list
+            prev->next = NULL;
+            free(curr->user);
+            free(curr);
+        } else {
+            printf_P(PSTR(LINKED_LIST_ERROR_MSG "\n"));
+        }
+    } else {
+        printf_P(PSTR(CARD_NOT_FOUND_MSG));
+    }
+}

src/rfid.h

@@ -0,0 +1,34 @@
+/*   Copyright (C) 2016 Arti Zirk <arti.zirk@gmail.com>
+ *
+ *   This file is part of I237 Door Access program.
+ *
+ *   I237 Door Access 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   I237 Door Access 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 I237 Door Access.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef _RFID_H_
+#define _RFID_H_
+
+typedef struct card {
+    uint8_t uid_size;
+    uint8_t uid[10];
+    char *user;
+    struct card *next;
+} card_t;
+
+extern card_t *head;
+extern card_t* rfid_find_card(const card_t *card);
+extern void rfid_add_card(const card_t *card);
+extern void rfid_list_cards(void);
+extern void rfid_remove_card_by_user(const char *user);
+
+#endif /* _RFID_H_ */

src/uart_wrap.c

@@ -1,7 +1,28 @@
+/*   Copyright (C) 2016 Arti Zirk <arti.zirk@gmail.com>
+ *
+ *   This file is part of I237 Door Access program.
+ *
+ *   I237 Door Access 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   I237 Door Access 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 I237 Door Access.  If not, see <http://www.gnu.org/licenses/>.
+ */
 #include <avr/io.h>
 #include <stdio.h>
 #include "../lib/andygock_avr-uart/uart.h"
 
+
+#define UART_STATUS_MASK    0x00FF
+
+
 int uart0_putc_wrap(char c, FILE *stream)
 {
     (void) stream;
@@ -14,6 +35,7 @@ int uart0_putc_wrap(char c, FILE *stream)
     return 0;
 }
 
+
 int uart0_getc_wrap(FILE *stream)
 {
     (void) stream;
@@ -21,9 +43,10 @@ int uart0_getc_wrap(FILE *stream)
     // this function is only called out when there is at least one character
     // available in the input buffer (see main.c line 114) then error checking
     // is not currently necessary.
-    return (char)uart0_getc();
+    return uart0_getc() & UART_STATUS_MASK;
 }
 
+
 int uart3_putc_wrap(char c, FILE *stream)
 {
     (void) stream;

src/uart_wrap.h

@@ -1,3 +1,20 @@
+/*   Copyright (C) 2016 Arti Zirk <arti.zirk@gmail.com>
+ *
+ *   This file is part of I237 Door Access program.
+ *
+ *   I237 Door Access 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   I237 Door Access 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 I237 Door Access.  If not, see <http://www.gnu.org/licenses/>.
+ */
 #ifndef _UART_WRAP_H_
 #define _UART_WRAP_H_