Initial commit: SUB-OS 64-Bit Production Monolithic Operating System with LazyBox userland suite

drivers/char/keyboard.c

@@ -0,0 +1,139 @@
+#include <drivers/keyboard.h>
+#include <drivers/tty.h>
+#include <arch/x86_64/isr.h>
+#include <arch/x86_64/pic.h>
+#include <arch/x86_64/io.h>
+
+#define KEYBOARD_DATA_PORT    0x60
+#define KEYBOARD_STATUS_PORT  0x64
+#define KEYBOARD_BUFFER_SIZE  128
+
+static volatile uint16_t key_buffer[KEYBOARD_BUFFER_SIZE];
+static volatile int buffer_head = 0;
+static volatile int buffer_tail = 0;
+
+static bool shift_pressed = false;
+static bool ctrl_pressed  = false;
+static bool alt_pressed   = false;
+static bool capslock      = false;
+static bool extended_code = false;
+
+static const char scancode_ascii[128] = {
+    0,   27,  '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '-', '=', '\b',
+    '\t', 'q', 'w', 'e', 'r', 't', 'y', 'u', 'i', 'o', 'p', '[', ']', '\n',
+    0,   'a', 's', 'd', 'f', 'g', 'h', 'j', 'k', 'l', ';', '\'', '`',
+    0,   '\\', 'z', 'x', 'c', 'v', 'b', 'n', 'm', ',', '.', '/', 0,
+    '*', 0,   ' ', 0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0
+};
+
+static const char scancode_ascii_shift[128] = {
+    0,   27,  '!', '@', '#', '$', '%', '^', '&', '*', '(', ')', '_', '+', '\b',
+    '\t', 'Q', 'W', 'E', 'R', 'T', 'Y', 'U', 'I', 'O', 'P', '{', '}', '\n',
+    0,   'A', 'S', 'D', 'F', 'G', 'H', 'J', 'K', 'L', ':', '"', '~',
+    0,   '|', 'Z', 'X', 'C', 'V', 'B', 'N', 'M', '<', '>', '?', 0,
+    '*', 0,   ' ', 0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0
+};
+
+static void buffer_enqueue(uint16_t key) {
+    int next = (buffer_head + 1) % KEYBOARD_BUFFER_SIZE;
+    if (next != buffer_tail) {
+        key_buffer[buffer_head] = key;
+        buffer_head = next;
+    }
+}
+
+static void keyboard_interrupt_handler(registers_t* regs) {
+    (void)regs;
+    uint8_t scancode = inb(KEYBOARD_DATA_PORT);
+
+    if (scancode == 0xE0) {
+        extended_code = true;
+        return;
+    }
+
+    if (scancode & 0x80) { // Key Release
+        uint8_t released = scancode & 0x7F;
+        if (released == 0x2A || released == 0x36) shift_pressed = false;
+        else if (released == 0x1D) ctrl_pressed = false;
+        else if (released == 0x38) alt_pressed = false;
+        extended_code = false;
+        return;
+    }
+
+    // Key Press
+    if (scancode == 0x2A || scancode == 0x36) { shift_pressed = true; return; }
+    if (scancode == 0x1D) { ctrl_pressed = true; return; }
+    if (scancode == 0x38) { alt_pressed = true; return; }
+    if (scancode == 0x3A) { capslock = !capslock; return; }
+
+    // Alt + F1..F4 -> Switch Virtual Consoles
+    if (alt_pressed) {
+        if (scancode >= 0x3B && scancode <= 0x3E) { // F1 - F4
+            tty_switch(scancode - 0x3B);
+            return;
+        }
+    }
+
+    if (extended_code) {
+        extended_code = false;
+        switch (scancode) {
+            case 0x48: buffer_enqueue(KEY_UP); return;
+            case 0x50: buffer_enqueue(KEY_DOWN); return;
+            case 0x4B: buffer_enqueue(KEY_LEFT); return;
+            case 0x4D: buffer_enqueue(KEY_RIGHT); return;
+            case 0x47: buffer_enqueue(KEY_HOME); return;
+            case 0x4F: buffer_enqueue(KEY_END); return;
+            case 0x49: buffer_enqueue(KEY_PAGE_UP); return;
+            case 0x51: buffer_enqueue(KEY_PAGE_DOWN); return;
+            case 0x52: buffer_enqueue(KEY_INSERT); return;
+            case 0x53: buffer_enqueue(KEY_DELETE); return;
+        }
+    }
+
+    // Function Keys F1-F12
+    if (scancode >= 0x3B && scancode <= 0x44) {
+        buffer_enqueue(KEY_F1 + (scancode - 0x3B));
+        return;
+    }
+
+    if (ctrl_pressed) {
+        if (scancode == 0x2E) { buffer_enqueue(0x03); return; } // Ctrl+C
+        if (scancode == 0x26) { buffer_enqueue(0x0C); return; } // Ctrl+L
+        if (scancode == 0x20) { buffer_enqueue(0x04); return; } // Ctrl+D
+    }
+
+    bool use_shift = shift_pressed ^ capslock;
+    char c = use_shift ? scancode_ascii_shift[scancode] : scancode_ascii[scancode];
+    if (c) {
+        buffer_enqueue((uint16_t)c);
+    }
+}
+
+void keyboard_init(void) {
+    buffer_head = 0;
+    buffer_tail = 0;
+
+    isr_register_handler(33, keyboard_interrupt_handler); // IRQ1
+    pic_clear_mask(1);
+}
+
+bool keyboard_has_key(void) {
+    return buffer_head != buffer_tail;
+}
+
+uint16_t keyboard_get_key(void) {
+    while (!keyboard_has_key()) {
+        hlt();
+    }
+    uint16_t key = key_buffer[buffer_tail];
+    buffer_tail = (buffer_tail + 1) % KEYBOARD_BUFFER_SIZE;
+    return key;
+}
+
+char keyboard_get_char(void) {
+    uint16_t key = keyboard_get_key();
+    if (key & KEY_SPECIAL_FLAG) return 0;
+    return (char)(key & 0xFF);
+}