Fix line input mode ignoring characters ABCD

src/readline.c

@@ -0,0 +1,277 @@
+/*
+ * tio - a serial device I/O tool
+ *
+ * Copyright (c) 2014-2024  Martin Lund
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#include "print.h"
+#include "misc.h"
+
+#define MAX_LINE_LEN PATH_MAX
+#define MAX_HISTORY 1000
+
+static char line[MAX_LINE_LEN] = {};
+static int history_count = 0;
+static int history_index = 0;
+static int line_length = 0;
+static int cursor_pos = 0;
+static int escape = 0;
+
+static char *history[MAX_HISTORY];
+
+static void print_line(const char *string, int cursor_pos)
+{
+    clear_line();
+    print("%s", string);
+    print("\r"); // Move the cursor back to the beginning
+    for (int i = 0; i < cursor_pos; ++i)
+    {
+        print("\x1b[C"); // Move the cursor right
+    }
+}
+
+void readline_init(void)
+{
+    history_count = 0;
+    history_index = 0;
+
+    for (int i = 0; i < MAX_HISTORY; ++i)
+    {
+        history[i] = NULL;
+    }
+
+    line[0] = 0;
+    line_length = 0;
+    cursor_pos = 0;
+    escape = 0;
+}
+
+char * readline_get(void)
+{
+    return line;
+}
+
+static void readline_input_char(char input_char)
+{
+    if (line_length < MAX_LINE_LEN - 1)
+    {
+        memmove(&line[cursor_pos + 1], &line[cursor_pos], line_length - cursor_pos);
+        line[cursor_pos] = input_char;
+        line_length++;
+        cursor_pos++;
+        line[line_length] = '\0';
+        print_line(line, cursor_pos);
+    }
+    escape = 0;
+}
+
+static void readline_input_cr(void)
+{
+    if (line_length > 0)
+    {
+        // Save to history
+        if (history_count < MAX_HISTORY)
+        {
+            history[history_count] = strndup(line, line_length);
+            history_count++;
+        }
+        else
+    {
+            free(history[0]);
+            memmove(&history[0], &history[1], (MAX_HISTORY - 1) * sizeof(char*));
+            history[MAX_HISTORY - 1] = strndup(line, line_length);
+        }
+    }
+
+    line[line_length] = '\0';
+    if (option.local_echo == false)
+    {
+        clear_line();
+    }
+    else
+    {
+        print("\r\n");
+    }
+
+    line_length = 0;
+    cursor_pos = 0;
+    history_index = history_count;
+    escape = 0;
+}
+
+static void readline_input_bs(void)
+{
+    if (cursor_pos > 0)
+    {
+        memmove(&line[cursor_pos - 1], &line[cursor_pos], line_length - cursor_pos);
+        line_length--;
+        cursor_pos--;
+        line[line_length] = '\0';
+        print_line(line, cursor_pos);
+    }
+    escape = 0;
+}
+
+static void readline_input_escape(void)
+{
+    escape = 1;
+}
+
+static void readline_input_left_bracket(void)
+{
+    if (escape == 1)
+    {
+        escape = 2;
+    }
+    else
+    {
+        escape = 0;
+    }
+}
+
+static void readline_input_A(void)
+{
+    if (escape == 2)
+    {
+        // Up arrow
+        if (history_index > 0)
+        {
+            history_index--;
+            strncpy(line, history[history_index], MAX_LINE_LEN-1);
+            line_length = strlen(line);
+            cursor_pos = line_length;
+            print_line(line, cursor_pos);
+        }
+    }
+    else
+    {
+        readline_input_char('A');
+    }
+
+    escape = 0;
+}
+
+static void readline_input_B(void)
+{
+    if (escape == 2)
+    {
+        // Down arrow
+        if (history_index < history_count - 1)
+        {
+            history_index++;
+            strncpy(line, history[history_index], MAX_LINE_LEN-1);
+            line_length = strlen(line);
+            cursor_pos = line_length;
+            print_line(line, cursor_pos);
+        }
+        else if (history_index == history_count - 1)
+        {
+            history_index++;
+            line_length = 0;
+            cursor_pos = 0;
+            line[line_length] = '\0';
+            print_line(line, cursor_pos);
+        }
+    }
+    else
+    {
+        readline_input_char('B');
+    }
+
+    escape = 0;
+}
+
+static void readline_input_C(void)
+{
+    if (escape == 2)
+    {
+        // Right arrow
+        if (cursor_pos < line_length)
+        {
+            cursor_pos++;
+            print("\x1b[C");
+        }
+    }
+    else
+    {
+        readline_input_char('C');
+    }
+
+    escape = 0;
+}
+
+static void readline_input_D(void)
+{
+    if (escape == 2)
+    {
+        // Left arrow
+        if (cursor_pos > 0)
+        {
+            cursor_pos--;
+            print("\b");
+        }
+    }
+    else
+    {
+        readline_input_char('D');
+    }
+
+    escape = 0;
+}
+
+void readline_input(char input_char)
+{
+    switch (input_char)
+    {
+        case '\r': // Carriage return
+            readline_input_cr();
+            break;
+
+        case 127: // Backspace
+            readline_input_bs();
+            break;
+
+        case 27: // Escape
+            readline_input_escape();
+            break;
+
+        case '[':
+            readline_input_left_bracket();
+            break;
+
+        case 'A':
+            readline_input_A();
+            break;
+
+        case 'B':
+            readline_input_B();
+            break;
+
+        case 'C':
+            readline_input_C();
+            break;
+
+        case 'D':
+            readline_input_D();
+            break;
+
+        default:
+            readline_input_char(input_char);
+            break;
+    }
+}