Add: read keyboard input (getch)

src/kernel/kb.c

@@ -2,6 +2,8 @@
 #include "../libc/stdio.h"
 #include "system.h"
 
+#define KEYBOARD_BUFFER_SIZE 256
+
 unsigned char kbdus[128] =
 {
     0,  27, '1', '2', '3', '4', '5', '6', '7', '8',	/* 9 */
@@ -42,6 +44,10 @@ unsigned char kbdus[128] =
     0,	/* All other keys are undefined */
 };
 
+static char keyboard_buffer[KEYBOARD_BUFFER_SIZE];
+static unsigned int keyboard_buffer_start = 0;
+static unsigned int keyboard_buffer_end = 0;
+
 void keyboard_handler()
 {
 	unsigned char scancode;
@@ -53,7 +59,12 @@ void keyboard_handler()
 	}
 	else 
 	{
-		putc(kbdus[scancode]);
+		char c = kbdus[scancode];
+		if (c)
+		{
+			keyboard_buffer[keyboard_buffer_end] = c;
+			keyboard_buffer_end = (keyboard_buffer_end+1) % KEYBOARD_BUFFER_SIZE;
+		}
 	}
 }
 
@@ -61,3 +72,12 @@ void keyboard_install()
 {
 	irq_install_handler(1, keyboard_handler);
 }
+
+char keyboard_getchar()
+{
+	while (keyboard_buffer_start == keyboard_buffer_end);
+
+	char c = keyboard_buffer[keyboard_buffer_start];
+	keyboard_buffer_start = (keyboard_buffer_start+1) % KEYBOARD_BUFFER_SIZE;
+	return c;
+}

src/kernel/kmain.c

@@ -4,6 +4,8 @@
 #include "idt.h"
 #include "system.h"
 
+#define BUFFER_SIZE 256
+
 int kmain(int retvalue)
 {
   
@@ -29,8 +31,13 @@ int kmain(int retvalue)
   // TODO: Fix scrolling bug (framebuffer driver)
   // TODO: Fix keyboard driver bug (some keys mapped weirdly) + add suport for SHIFT and backspace (deleting character)
   // TODO: Grub modules to load programs
-
   //timer_install();
   keyboard_install();
+
+  char input_buffer[BUFFER_SIZE];
+  colorputs("Enter something: ", 9);
+  get_input(input_buffer, BUFFER_SIZE);
+  printf("\nYou entered: %s\n", input_buffer);
+
   return retvalue;
 }

src/kernel/system.h

@@ -20,5 +20,6 @@ void irq_uninstall_handler(int irq);
 void timer_install();
 void delay(int ticks);
 void keyboard_install();
+char keyboard_getchar();
 #endif
 

src/libc/stdio.c

@@ -2,6 +2,7 @@
 #include "stdio.h"
 #include "string.h"
 #include "stdint.h"
+#include "../kernel/system.h"
 
 char* fb = (char *) 0x000B8000;
 const unsigned VGA_WIDTH = 80;
@@ -335,3 +336,23 @@ int* printf_number(int* argp, int length, bool sign, int radix)
 
   return argp;
 }
+
+int getch()
+{
+	return keyboard_getchar();
+}
+
+void get_input(char *buffer, int size) {
+	int index = 0;
+	char c;
+
+	while (index < size-1)
+	{
+		c = getch();
+		if (c == '\n') break;
+
+		buffer[index++] = c;
+		putc(c);
+	}
+	buffer[index] = '\0';
+}

src/libc/stdio.h

@@ -37,5 +37,7 @@ void colorputc(char c, unsigned int color);
 
 void printf(const char* fmt, ...);
 int* printf_number(int* argp, int length, bool sign, int radix);
+int getch();
+void get_input(char *buffer, int size);
 
 #endif