diff options
Diffstat (limited to 'terminal.asm')
| -rw-r--r-- | terminal.asm | 52 |
1 files changed, 38 insertions, 14 deletions
diff --git a/terminal.asm b/terminal.asm index 718a304..163aa7e 100644 --- a/terminal.asm +++ b/terminal.asm @@ -10,6 +10,8 @@ terminal: push bp mov bp, sp + mov byte [terminal_exit], 0 + mov ax, ds mov es, ax sub sp, 2 ; variable for buffer start address @@ -76,25 +78,29 @@ terminal: call strtok ; tokenize add sp, 2 * 3 + push cx ; push token count push ax ; push token array call terminal_check_input ; parse terminal input add sp, 2 * 1 + cmp byte [terminal_exit], 0 + jne .return + jmp .clear_buffer ; zero out buffer / start over .output: call putc jmp .read_command ; print input to screen as we type - jmp .do_prompt ; start over - - add sp, 2 - mov sp, bp - pop bp - ret + .return: + add sp, 2 + mov sp, bp + pop bp + ret terminal_check_input: + %define .token_count [bp + 6] %define .input_len [bp - 2] %define .scan_count [bp - 4] %define .compare_count [bp - 6] @@ -156,7 +162,6 @@ terminal_check_input: cmp ax, cx jne .compare_prefail - ;sub ax, 1 ; Modify strlen return value (+1 null terminator) mov .compare_count, ax ; Store return value of strlen in counter xor ax, ax xor dx, dx @@ -177,15 +182,18 @@ terminal_check_input: jmp .compare ; ... continue .compare_fail: - inc word .scan_count ; Increment builtin identifier string attempt count + inc word .scan_count ; Increment builtin identifier + ; string attempt count inc di - add di, word .compare_count ; Load the offset of the next builtin identifier + add di, word .compare_count ; Load the offset of the next + ; builtin identifier jmp .scan_builtins ; Continue scanning .compare_prefail: inc word .scan_count inc ax ; adjust for null terminator - add di, ax ; Load the offset of the next builtin identifier + add di, ax ; Load the offset of the next + ; builtin identifier jmp .scan_builtins @@ -193,12 +201,27 @@ terminal_check_input: mov bx, t_builtins_fn ; Load address of function pointer array mov cx, word .scan_count ; Load offset count shl cx, 1 ; Multiply offset count by 2 (next WORD) - add bx, cx ; Add offset to address of function pointer array + add bx, cx ; Add offset to address of function + ; pointer array + + .execute: + ; Call builtin command with arguments + mov si, .input_baseaddr ; argv - tokenized input string + mov cx, .token_count ; argc - token count + + add si, 2 ; argv offset is next token + dec cx ; argc minus one token - mov si, .input_baseaddr - push si ; address of next token + pushf ; save flags + pusha ; save registers + + push si + push cx call word [bx] ; Execute builtin command - add sp, 2 * 1 + add sp, 2 * 2 + + popa ; restore registers + popf ; restore flags .scan_no_match: popa @@ -213,5 +236,6 @@ t_msg_prompt_fmt: db '%s', 0 t_msg_prompt: db '$ ', 0 t_buffer_fmt: db '%s', 0 t_buffer: times T_BUFSZ db 0 +terminal_exit: db 0 %endif |