Added support for \n, \t and \\ in the string printing function

source/kernel/features/cli.asm

@@ -23,36 +23,29 @@ os_read_cli:
 
 .check_matches:			; Check if the user input matches any internal commands
 	; Help
-	mov di, user_input
+	mov si, user_input
-	mov si, help_string
+	mov di, help_string
 	call os_compare_strings
 	cmp cl, 1
 	je help
 
 	; Clear screen
-	mov di, user_input
+	mov si, user_input
-	mov si, clear_string
+	mov di, clear_string
 	call os_compare_strings
 	cmp cl, 1
 	je clear
 
 	; Reboot
-	mov di, user_input
+	mov si, user_input
-	mov si, reboot_string
+	mov di, reboot_string
 	call os_compare_strings
 	cmp cl, 1
-	je os_reboot
+	je power_reboot
-
-    ; Reboot
-	mov di, user_input
-	mov si, cat_string
-	call os_compare_strings
-	cmp cl, 1
-	je cat
 	
 	; Pong
-	mov di, user_input
+	mov si, user_input
-	mov si, pong_string
+	mov di, pong_string
 	call os_compare_strings
 	cmp cl, 1
 	je pong
@@ -63,7 +56,7 @@ os_read_cli:
 	mov si, unknown_command
 	call os_print_string
 	mov si, user_input
-	call os_print_string_nl
+	call os_print_string
 	jmp .finish
 
 .finish:
@@ -76,11 +69,7 @@ clear:
 
 help:
 	mov si, help_text
-	call os_print_string_nl
+	call os_print_string
-	call os_read_cli.finish
-
-cat:
-   call util_cat
 	call os_read_cli.finish
 
 pong:
@@ -88,7 +77,7 @@ pong:
 	call os_read_cli.finish
 
 section .data
-    welcome_text db 'Welcome to CrawOS, the Cool, Real and AWsome Operating System', 0
+    welcome_text db 'Welcome to CrawOS, the Cwick, Real and AWsome Operating System\n', 0
 	user_input times 20 db 0
 	prompt_length db 20
 	prompt db 'CrawOS sh> ', 0
@@ -97,6 +86,6 @@ section .data
 	reboot_string db 'REBOOT', 0
 	cat_string db 'CAT', 0
 	pong_string db 'PONG', 0
-	help_text db 'This is for Cowards: "HELP" for this help text, "CLEAR" to clear the screen, esc or "REBOOT" to reboot', 0
+	help_text db 'This is for Cowards:\n"HELP" for this helpful text,\n"CLEAR" to clear the screen,\n"REBOOT" or esc to reboot\n', 0
 	command_result_text db 'You typed: ', 0
-	unknown_command db 'Error: Unkown Command.. ', 0
+	unknown_command db 'Error: Unkown Command.. \n', 0

source/kernel/features/keyboard.asm

@@ -43,7 +43,7 @@ os_display_input:
 	jmp .check_key_pressed
 
 .esc_key:
-	call os_reboot
+	call power_reboot
 
 .enter_key:
 	mov al, 0

source/kernel/features/math.asm

@@ -0,0 +1,53 @@
+; LBA = index of data segment on disk
+; CHS = cylinder, header, sector
+; T = LBA/sectors per track
+; S = (LBA%sectors per track) + 1
+; H = T % heads
+; C = T / headers
+; input, LBA index: ax
+; sector number: cl
+; cylinder: ch
+; head: dh
+; Example where LBA = 50h (CHS = 2,0,9)
+; ax = 0050h, push this to the stack
+; dx = 0000h
+; dx = 50h % 12h = 0008h
+; ax = 50h / 12h = 0004h
+; dx = 0009h
+; cx = 0009h
+; dx = 0000h
+; dx = 04h % 02h = 0000h
+; ax = 04h / 02h = 0002h
+; dh = 00h (dx = 0000h)
+; ch = 02h (cx = 0209h)
+; ah = 00h (ax = 0002h)
+; cl = 09h OR 00h = 09h (cx = 0209h)
+; ax = 0050h
+; dl = 50h (dx = 0050h)
+; ax = 0050h
+; thus:
+; cylinder (ch) = 02h
+; head (cl) = 00h
+; sector (dh) = 09h
+os_lba_to_chs:
+    push ax
+    push dx
+
+    xor dx,dx ; clear dx
+    div word [bdb_sectors_per_track] ; (LBA % sectors per track) + 1 = sector
+    inc dx  ; sector, dx stores the remainder so we increment that.
+    mov cx,dx
+
+    xor dx,dx ; clear dx
+    div word [bdb_number_of_heads]
+    mov dh,dl ; head, dx stores remainder so we move that up 8 bits to dh
+
+    mov ch,al
+    shl ah, 6   ; * 32
+    or cl, ah   ; cylinder
+
+    pop ax
+    mov dl,al
+    pop ax
+
+    ret

source/kernel/features/power.asm

@@ -1,6 +1,9 @@
-os_reboot:
+power_reboot:
    	mov ax, 0x5307
    	mov bx, 0x0001
    	mov cx, 0x0003
    	int 0x19
 
+; Not done
+power_shutdown:
+   ret

source/kernel/features/strings.asm

@@ -6,21 +6,31 @@
 ; memory address 2: |s|n|a|k|e|0|     
 ;                    ^
 ;                   SI => lodsb loads value stored at SI to AX and then increments SI if DF is 0
+; Additionaly, if the di string ends and the relevant character in si contains a space, it will still return
+; the strings as being equal, this is to allow for command line arquments
 os_compare_strings:	
 	cld
 
 .compare:
+    mov al, 0
+    scasb
+    je .di_ended
+    dec di
 	lodsb
 	scasb			; Compare di to si
 	jne .unequal		; If they are not equal, jump to .unequal
-	cmp al, 0		; Check if string is finished
-	je .equal		; If it has, return true
 	jmp .compare		; Finally, repeat
 
 .unequal:
 	mov cl, 0		; Change to 0 if unquality is proven
 	ret
-
+.di_ended:
+   lodsb
+   cmp al, 20h ; 20h = space
+   je .equal
+   cmp al, 0
+   je .equal
+   jmp .unequal
 .equal:
 	mov cl, 1
 	ret
@@ -32,13 +42,13 @@ os_compare_strings:
 os_string_length:
    push si
    xor cl,cl ; Clear the al register
-.loop
+.loop:
    lodsb
    cmp al, 0
    je .finish
    inc cl
    jmp .loop
-.finish
+.finish:
    pop si
    ret
 
@@ -78,7 +88,7 @@ os_format_fat_filename:
 ; Convert a string to all upper/lower case
 ; INPUT: si pointing to a string
 ; OUPUT: the same string in memory will now be capitalised/decapitalised
-os_upper_case:
+os_upper_case: ; to upper case
     pusha
     mov di, si
 .loop:
@@ -98,7 +108,7 @@ os_upper_case:
     popa
     ret
 
-os_lower_case:
+os_lower_case: ; to lower case
     pusha
     mov di, si
 .loop:

source/kernel/features/text.asm

@@ -1,4 +1,7 @@
 ; SI = pointer to start of string to be printed
+; \n for newline
+; \t for tab
+; \\ for a single backslash
 os_print_string:
 	pusha
 
@@ -8,34 +11,43 @@ os_print_string:
 	lodsb				; Get char from si into al
 	cmp al, 0			; Compare al to 0
 	je .done			; If char is zero, end of string
+	cmp al, 5Ch			; backslash
+	je .backslash
 
 	int 10h				; Otherwise, print it
 	jmp .repeat			; And move on to next char
 
+   .backslash: ; If there is a '\', do what it says, \n for newline, \t for tab etc
+	  lodsb
+	  dec si
+	  cmp al, 6Eh		; 'n'
+	  je .newline
+	  cmp al, 74h	; \t
+	  je .tab
+	  cmp al, 5Ch ; '\'
+	  je .another_backslash
+	  jmp .repeat
+   .newline:
+	  mov al, 0Ah ; new line
+	  int 10h
+	  mov al, 0Dh ; carriage return
+	  int 10h
+	  jmp .finish_backslash
+   .tab:
+	  mov al, 09h	; tab
+	  int 10h
+	  jmp .finish_backslash
+   .another_backslash: ; This just prints 1 backslash
+	  mov al, 5Ch
+	  int 10h
+	  jmp .finish_backslash
+   .finish_backslash:
+	  inc si
+	  jmp .repeat
 .done:
 	popa
 	ret
 
-; Exact same as the above procedure, but this adds a newline 
-; after priting, similar to the difference between Rust's print! and println!
-os_print_string_nl:				
-	pusha
-
-	mov ah, 0Eh			; int 10h teletype function, we're telling the BIOS we will print something
-
-.repeat:
-	lodsb				; Get char from si into al
-	cmp al, 0			; Compare al to 0
-	je .done			; If char is zero, end of string
-
-	int 10h				; Otherwise, print it
-	jmp .repeat			; And move on to next char
-
-.done:
-	call os_print_newline
-	popa
-	ret
-
 ; --------------------------------------------
 
 os_print_newline:

source/kernel/features/utils.asm

@@ -1,18 +0,0 @@
-; Outputs the contents of a file
-util_cat:
-   pusha
-
-   call os_print_newline
-
-   mov si, cat_prompt
-   call os_print_string
-
-   mov ax, 11 ; length of input
-   mov di, user_input
-
-   popa
-   ret
-
-
-section .data:
-   cat_prompt db 'Enter file name: ', 0

source/kernel/kernel.asm

@@ -3,17 +3,10 @@ BITS 16
 
 start:
    mov si, boot_message
-   call os_print_string_nl
+   call os_print_string
 
    mov si, help_text
-   call os_print_string_nl
+   call os_print_string
-
-   mov si, file_name
-   call os_print_string_nl
-   mov di, fat_file_name
-   call os_format_fat_filename
-   mov si, fat_file_name
-   call os_print_string_nl
 
    call os_start_cli
    hlt
@@ -21,9 +14,7 @@ start:
 halt:
    jmp halt
 
-boot_message: db 'OK] Kernel successfully loaded!', 0
+boot_message: db 'OK] Kernel successfully loaded!\n', 0
-file_name: db 'hello.cws', 0
-fat_file_name: db '           ',0 ; 11 characters
 
 ; ------------------------------------------------------------------
 ; FEATURES -- Code to pull into the kernel
@@ -33,6 +24,6 @@ fat_file_name: db '           ',0 ; 11 characters
 	%INCLUDE "source/kernel/features/power.asm"
 	%INCLUDE "source/kernel/features/strings.asm"
 	%INCLUDE "source/kernel/features/graphics.asm"
-    %INCLUDE "source/kernel/features/utils.asm"
+    %INCLUDE "source/kernel/features/disk.asm"
 ; GAMES -- Games that I wrote for it
 	%INCLUDE "source/kernel/games/pong.asm"