Adding tty

8 files changed, 250 insertions, 128 deletions

diff --git a/Makefile b/Makefile
index 127e576..9e7e302 100644
--- a/Makefile
+++ b/Makefile
@@ -2,7 +2,7 @@ ARCH=i686-elf
 
 CC=$(ARCH)-gcc
 AS=$(ARCH)-as
-CFLAGS=-ffreestanding -O2 -Wall -Wextra -ggdb
+CFLAGS=-ffreestanding -O2 -Wall -Wextra
 
 MKDIR=mkdir -p
 RM=rm -rf
@@ -15,7 +15,7 @@ ISO_DIR=isodir
 
 TARGET=myos
 
-OBJ_FILES=boot.o kernel.o gdt.o idt.o
+OBJ_FILES=boot.o kernel.o gdt.o idt.o keyboard.o vga.o string.o tty.o
 CRTBEGIN_OBJ=$(shell $(CC) -print-file-name=crtbegin.o)
 CRTEND_OBJ=$(shell $(CC) -print-file-name=crtend.o)
 OBJ=$(BUILD_DIR)/crti.o $(CRTBEGIN_OBJ) $(patsubst %,$(BUILD_DIR)/%,$(OBJ_FILES)) $(CRTEND_OBJ) $(BUILD_DIR)/crtn.o
diff --git a/src/boot.s b/src/boot.s
index b88e8f7..6fe5ab8 100644
--- a/src/boot.s
+++ b/src/boot.s
@@ -64,8 +64,9 @@ stack_top:
 .type _start, @function
 _start:
 	call init_gdt_table
-	ljmp $CODE_SEGMENT, $next
-	next:
+	ljmp $CODE_SEGMENT, $code
+	
+code:
 	movw $DATA_SEGMENT, %ax
 	movw %ax, %ds
 	movw %ax, %es
diff --git a/src/kernel.c b/src/kernel.c
index 0882580..0ad3b66 100644
--- a/src/kernel.c
+++ b/src/kernel.c
@@ -1,129 +1,13 @@
-#include<stdbool.h>
-#include<stddef.h>
-#include<stdint.h>
-#include"vga.h"
-
-static const size_t VGA_WIDTH = 80;
-static const size_t VGA_HEIGHT = 25;
-
-#define PIC1_COMMAND_PORT 0x20
-#define PIC1_DATA_PORT 0x21
-#define PIC2_COMMAND_PORT 0xA0
-#define PIC2_DATA_PORT 0xA1
-// IO Ports for Keyboard
-#define KEYBOARD_DATA_PORT 0x60
-#define KEYBOARD_STATUS_PORT 0x64
-
-extern char ioport_in(uint8_t port);
-extern void ioport_out(uint8_t port, char data);
-
-static inline uint8_t vga_entry_color(enum vga_color fg, enum vga_color bg) 
-{
-    return fg | bg << 4;
-}
- 
-static inline uint16_t vga_entry(unsigned char uc, uint8_t color) 
-{
-    return (uint16_t) uc | (uint16_t) color << 8;
-}
- 
-size_t terminal_row;
-size_t terminal_column;
-uint8_t terminal_color;
-uint16_t* terminal_buffer;
- 
-void terminal_initialize(void) 
-{
-    terminal_row=0;
-    terminal_column=0;
-    terminal_color=vga_entry_color(VGA_COLOR_LIGHT_GREY, VGA_COLOR_BLACK);
-    terminal_buffer=(uint16_t*) 0xB8000;
-    for(size_t y=0;y<VGA_HEIGHT;y++)
-    {
-	for(size_t x=0;x<VGA_WIDTH;x++)
-	{
-	    const size_t index=y*VGA_WIDTH+x;
-	    terminal_buffer[index]=vga_entry(' ', terminal_color);
-	}
-    }
-}
- 
-void terminal_putentryat(char c, uint8_t color, size_t x, size_t y) 
-{
-    const size_t index=y*VGA_WIDTH+x;
-    terminal_buffer[index]=vga_entry(c, color);
-}
-
-void movescreen()
-{
-    terminal_row--;
-    for(size_t i=0;i<VGA_HEIGHT;i++) for(size_t j=0;j<VGA_WIDTH;j++) terminal_buffer[i*VGA_WIDTH+j]=terminal_buffer[(i+1)*VGA_WIDTH+j];
-}
- 
-void terminal_putchar(char c) 
-{
-    if(c=='\n') terminal_column = 0,terminal_row++;
-    else
-    {
-	terminal_putentryat(c, terminal_color, terminal_column, terminal_row);
-	if (++terminal_column==VGA_WIDTH) terminal_column=0,terminal_row++;
-    }
-    if (terminal_row==VGA_HEIGHT) movescreen();
-}
- 
-void terminal_writestring(const char* data) 
-{
-    for(int i=0;data[i]!='\0';i++) terminal_putchar(data[i]);
-}
-
-void init_keyboard()
-{
-    // 0xFD = 1111 1101 in binary. enables only IRQ1
-    // Why IRQ1? Remember, IRQ0 exists, it's 0-based
-    ioport_out(PIC1_DATA_PORT, 0xFD);
-}
-
-#include"keyboard.h"
-void handle_keyboard_interrupt()
-{
-    // Write end of interrupt (EOI)
-    ioport_out(PIC1_COMMAND_PORT, 0x20);
-    unsigned char status = ioport_in(KEYBOARD_STATUS_PORT);
-
-    // Lowest bit of status will be set if buffer not empty
-    // (thanks mkeykernel)
-    if (status & 0x1)
-    {
-	char keycode = ioport_in(KEYBOARD_DATA_PORT);
-	if (keycode < 0 || (uint8_t)keycode >= 128) return;
-
-	if(keycode==14)
-	{
-	    if(terminal_column) terminal_column--;
-	    terminal_putchar(keyboard[keycode]);
-	    terminal_column--;
-	    return;
-	}
-
-	terminal_putchar(keyboard[keycode]);
-
-    }
-}
-void print_message()
-{
-    for(size_t i=0;i<50;i++)
-    {
-       for(size_t j=0;j<i;j++) terminal_writestring("#");
-       terminal_writestring("Hello, kernel World!\n");
-    }
-}
+void terminal_initialize(void);
+void init_idt_table(void);
+void init_keyboard(void);
+void prompt(void);
 
 void kernel_main(void)
 {
     terminal_initialize();
-    print_message();
     init_idt_table();
     init_keyboard();
-    terminal_writestring("First part is working\n");
-    while(1);
+    prompt();
+    while(1) __asm__("hlt\n\t");
 }
diff --git a/src/keyboard.c b/src/keyboard.c
new file mode 100644
index 0000000..987c7a2
--- /dev/null
+++ b/src/keyboard.c
@@ -0,0 +1,78 @@
+#include<stdbool.h>
+#include<stddef.h>
+#include<stdint.h>
+#include"keyboard.h"
+
+#define BUFFER_SIZE 200
+char buffer[BUFFER_SIZE];
+size_t buffer_index=0;
+
+#define PIC1_COMMAND_PORT 0x20
+#define PIC1_DATA_PORT 0x21
+#define PIC2_COMMAND_PORT 0xA0
+#define PIC2_DATA_PORT 0xA1
+// IO Ports for Keyboard
+#define KEYBOARD_DATA_PORT 0x60
+#define KEYBOARD_STATUS_PORT 0x64
+
+extern char ioport_in(uint8_t port);
+extern void ioport_out(uint8_t port, char data);
+
+void previous_field();
+void terminal_putchar(char c);
+void tty(char *buffer);
+void prompt();
+
+void init_keyboard()
+{
+    // 0xFD = 1111 1101 in binary. enables only IRQ1
+    // Why IRQ1? Remember, IRQ0 exists, it's 0-based
+    ioport_out(PIC1_DATA_PORT, 0xFD);
+}
+
+void backspace()
+{
+    if(buffer_index<=0) return;
+
+    previous_field();
+    terminal_putchar(' ');
+    previous_field();
+    buffer[--buffer_index]='\0';
+    return;
+}
+
+void enter()
+{
+    terminal_putchar('\n');
+    if(buffer_index>0)
+    {
+	tty(buffer);
+	for(int i=0;i<BUFFER_SIZE;i++) buffer[i]='\0';
+	buffer_index=0;
+    }
+    prompt();
+    return;
+}
+
+void handle_keyboard_interrupt()
+{
+    // Write end of interrupt (EOI)
+    ioport_out(PIC1_COMMAND_PORT, 0x20);
+    unsigned char status = ioport_in(KEYBOARD_STATUS_PORT);
+
+    // Lowest bit of status will be set if buffer not empty
+    if (status & 0x1)
+    {
+	int16_t keycode = ioport_in(KEYBOARD_DATA_PORT);
+	if (keycode < 0 || keycode >= 128) return;
+
+	if(keycode==14) backspace();
+	else if(keycode==28) enter();
+	else
+	{
+	    buffer[buffer_index++]=keyboard[keycode];
+	    terminal_putchar(keyboard[keycode]);
+	}
+
+    }
+}
diff --git a/src/keyboard.h b/src/keyboard.h
index 53846e6..5de7e10 100644
--- a/src/keyboard.h
+++ b/src/keyboard.h
@@ -6,11 +6,11 @@ unsigned char keyboard[128] = {
   // -------- 10 to 19 --------
   '9','0','-','=',
   ' ', // Backspace
-  ' ', // Tab
+  '	', // Tab
   'q','w','e','r',
   // -------- 20 to 29 --------
   't','y','u','i','o','p','[',']',
-  '\n', // Enter
+  ' ', // Enter
   ' ', // left Ctrl
   // -------- 30 to 39 --------
   'a','s','d','f','g','h','j','k','l',';',
diff --git a/src/string.c b/src/string.c
new file mode 100644
index 0000000..4683470
--- /dev/null
+++ b/src/string.c
@@ -0,0 +1,34 @@
+#include<stdbool.h>
+#include<stddef.h>
+#include<stdint.h>
+
+bool stringcmp(char *str1,char *str2)
+{
+    size_t i;
+    for(i=0;str1[i]||str2[i];i++) if(str1[i]!=str2[i]) return 0;
+    if(str1[i]==str2[i]) return 1;
+    return 0;
+}
+
+size_t pieces(char pieces[15][15],char *buffer)
+{
+    for(size_t x=0;x<15;x++) for(size_t y=0;y<15;y++) pieces[x][y]='\0';
+
+    size_t i=0,j=0,r=0;
+    while(buffer[i]==' '&&buffer[i]!='\0') i++;
+    for(;buffer[i]!='\0';i++)
+    {
+	if(buffer[i]==' ')
+	{
+	    while(buffer[i]==' '&&buffer[i]!='\0') i++;
+	    j=0;
+	    r++;
+	    i--;
+	}
+	else
+	{
+	    pieces[r][j++]=buffer[i];
+	}
+    }
+    return r+1;
+}
diff --git a/src/tty.c b/src/tty.c
new file mode 100644
index 0000000..c3fe295
--- /dev/null
+++ b/src/tty.c
@@ -0,0 +1,32 @@
+#include<stdbool.h>
+#include<stddef.h>
+#include<stdint.h>
+bool stringcmp(char *str1,char *str2);
+size_t pieces(char pieces[][15],char *buffer);
+void clear();
+void terminal_writestring(const char* data);
+void terminal_putchar(char c);
+
+void echo(size_t numberof,char parts[][15])
+{
+    for(size_t i=1;i<numberof;i++)
+    {
+	terminal_writestring(parts[i]);
+	terminal_putchar(' ');
+    }
+    terminal_putchar('\n');
+}
+
+void tty(char *buffer)
+{
+    char parts[15][15];
+    size_t numberof=pieces(parts,buffer);
+    if(stringcmp(parts[0],"clear")) clear();
+    else if(stringcmp(parts[0],"echo")) echo(numberof,parts);
+    else
+    {
+	terminal_writestring("command not found: ");
+	terminal_writestring(parts[0]);
+	terminal_putchar('\n');
+    }
+}
diff --git a/src/vga.c b/src/vga.c
new file mode 100644
index 0000000..71faa1a
--- /dev/null
+++ b/src/vga.c
@@ -0,0 +1,93 @@
+#include<stdbool.h>
+#include<stddef.h>
+#include<stdint.h>
+#include"vga.h"
+static const size_t VGA_WIDTH = 80;
+static const size_t VGA_HEIGHT = 25;
+
+extern char ioport_in(uint8_t port);
+extern void ioport_out(uint8_t port, char data);
+
+bool stringcmp(char *str1,char *str2);
+
+static inline uint8_t vga_entry_color(enum vga_color fg, enum vga_color bg)
+{
+    return fg | bg << 4;
+}
+ 
+static inline uint16_t vga_entry(unsigned char uc, uint8_t color)
+{
+    return (uint16_t) uc | (uint16_t) color << 8;
+}
+ 
+size_t terminal_row;
+size_t terminal_column;
+uint8_t terminal_color;
+uint16_t* terminal_buffer;
+ 
+void terminal_initialize()
+{
+    terminal_row=0;
+    terminal_column=0;
+    terminal_color=vga_entry_color(VGA_COLOR_LIGHT_GREY, VGA_COLOR_BLACK);
+    terminal_buffer=(uint16_t*) 0xB8000;
+    for(size_t y=0;y<VGA_HEIGHT;y++)
+    {
+	for(size_t x=0;x<VGA_WIDTH;x++)
+	{
+	    const size_t index=y*VGA_WIDTH+x;
+	    terminal_buffer[index]=vga_entry(' ', terminal_color);
+	}
+    }
+}
+
+void terminal_putentryat(char c, uint8_t color, size_t x, size_t y)
+{
+    const size_t index=y*VGA_WIDTH+x;
+    terminal_buffer[index]=vga_entry(c, color);
+}
+
+void movescreen()
+{
+    terminal_row--;
+    for(size_t i=0;i<VGA_HEIGHT;i++) for(size_t j=0;j<VGA_WIDTH;j++) terminal_buffer[i*VGA_WIDTH+j]=terminal_buffer[(i+1)*VGA_WIDTH+j];
+}
+
+void next_field()
+{
+    if(++terminal_column==VGA_WIDTH) terminal_column=0,terminal_row++;
+}
+
+void previous_field()
+{
+    if(terminal_column) terminal_column--;
+    else terminal_row--,terminal_column=VGA_WIDTH-1;
+}
+ 
+void terminal_putchar(char c)
+{
+    if(c=='\n') terminal_column=0,terminal_row++;
+    else
+    {
+	terminal_putentryat(c, terminal_color, terminal_column, terminal_row);
+	next_field();
+    }
+    if (terminal_row==VGA_HEIGHT) movescreen();
+}
+ 
+void terminal_writestring(const char* data)
+{
+    for(int i=0;data[i]!='\0';i++) terminal_putchar(data[i]);
+}
+
+void prompt()
+{
+    terminal_writestring("[user@myos] > ");
+}
+
+void clear()
+{
+    for(size_t i=0;i<VGA_HEIGHT;i++) for(size_t j=0;j<VGA_WIDTH;j++) terminal_putchar(' ');
+    terminal_column=0;
+    terminal_row=0;
+}