[FL-1063} LF-RFID Cli (#515)

* App lfrfid: update emulator to process external data.
* App lfrfid: cleanup emulator
* App lfrfid: cli interface
* Lib: arguments parser lib

Co-authored-by: あく <alleteam@gmail.com>

lib/args/args.c

@@ -0,0 +1,76 @@
+#include "args.h"
+
+size_t args_get_first_word_length(string_t args) {
+    size_t ws = string_search_char(args, ' ');
+    if(ws == STRING_FAILURE) {
+        ws = strlen(string_get_cstr(args));
+    }
+
+    return ws;
+}
+
+size_t args_length(string_t args) {
+    return strlen(string_get_cstr(args));
+}
+
+bool args_read_string_and_trim(string_t args, string_t word) {
+    size_t cmd_length = args_get_first_word_length(args);
+
+    if(cmd_length == 0) {
+        return false;
+    }
+
+    string_set_n(word, args, 0, cmd_length);
+    string_right(args, cmd_length);
+    string_strim(args);
+
+    return true;
+}
+
+bool args_char_to_hex_nibble(char c, uint8_t* nibble) {
+    if((c >= '0' && c <= '9') || (c >= 'A' && c <= 'F') || (c >= 'a' && c <= 'f')) {
+        if((c >= '0' && c <= '9')) {
+            *nibble = c - '0';
+        } else if((c >= 'A' && c <= 'F')) {
+            *nibble = c - 'A' + 10;
+        } else {
+            *nibble = c - 'a' + 10;
+        }
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool args_char_to_hex(char hi_nibble, char low_nibble, uint8_t* byte) {
+    uint8_t hi_nibble_value = 0;
+    uint8_t low_nibble_value = 0;
+    bool result = false;
+
+    if(args_char_to_hex_nibble(hi_nibble, &hi_nibble_value)) {
+        if(args_char_to_hex_nibble(low_nibble, &low_nibble_value)) {
+            result = true;
+            *byte = (hi_nibble_value << 4) | low_nibble_value;
+        }
+    }
+
+    return result;
+}
+
+bool args_read_hex_bytes(string_t args, uint8_t* bytes, uint8_t bytes_count) {
+    bool result = true;
+    const char* str_pointer = string_get_cstr(args);
+
+    if(args_get_first_word_length(args) == (bytes_count * 2)) {
+        for(uint8_t i = 0; i < bytes_count; i++) {
+            if(!args_char_to_hex(str_pointer[i * 2], str_pointer[i * 2 + 1], &(bytes[i]))) {
+                result = false;
+                break;
+            }
+        }
+    } else {
+        result = false;
+    }
+
+    return result;
+}