+; sped - the stupidly pointless editor
+; written by pinosaur
+%include "fileutils.S"
+
+global main
+extern printf
+extern fflush
+extern stdout
+
+; macros
%macro write_str 2
mov eax, 4
mov ebx, 1
%endmacro
section .data
- msg db "SPED - the stupidly pointless editor", 0x0a
- len equ $ - msg
+ banner_str db `SPED - the stupidly pointless editor\n`, 0x00
+ nofile_str db `no file provided\n`, 0x00
+ prompt_str db `sped > `, 0x00
+ invalidcommand_str db `invalid command\n`, 0x00
+ charcount_str db `read %i chars\n`, 0x00
+
+section .bss
+ buffer resb 4
+ buffer_lines resb 4
+ cur_line resb 4
section .text
-global _start
-_start:
- write_str msg, len
+main:
+ %define _ARGC 8
+ %define _ARGV 12
+
+ push ebp
+ mov ebp, esp
+ ; read command line args
+ mov ecx, [ebp+_ARGC]
+ cmp ecx, 1
+ jg _main_existing
+
+ ; display error msg if no file
+ push nofile_str
+ call printf
mov eax, 1
- mov ebx, 42
- int 0x80
+ jmp _main_exit
+
+ _main_existing:
+ mov ebx, DWORD [ebp+_ARGV]
+ add ebx, 4 ; first user arg is filename
+ push DWORD [ebx]
+ call readFile
+
+ mov [buffer], eax
+ mov [buffer_lines], ebx
+ mov DWORD [cur_line], 0x00
+
+ call repl
+
+ mov eax, 0
+ jmp _main_exit
+
+ _main_exit:
+ %undef _ARGC
+ %undef _ARGV
+
+ mov esp, ebp
+ pop ebp
+ ret
+
+; prompt for user
+; no args - reads from globals
+repl:
+
+ %define CMDSTR 4 ; the previous line read from user
+
+ push ebp
+ mov ebp, esp
+
+ sub esp, 4
+
+ _repl_loop:
+
+ ; print the prompt
+ push prompt_str
+ call printf
+ push DWORD [stdout]
+ call fflush
+
+ ; read line from stdin
+ push 0
+ call readLine
+
+ mov DWORD [ebp-CMDSTR], eax
+
+ ; commands are single char for now
+ cmp ecx, 1
+ jne _repl_invalid
+
+ ; parse commands
+ mov eax, DWORD [ebp-CMDSTR]
+ mov eax, [eax]
+
+ ; q exists program
+ mov eax, DWORD [ebp-CMDSTR]
+ cmp BYTE [eax], 'q'
+ jne _repl_cmd_quit_end
+ jmp _repl_exit
+ _repl_cmd_quit_end:
+
+
+ _repl_invalid:
+ push invalidcommand_str
+ call printf
+
+ _repl_continue:
+ jmp _repl_loop
+
+ _repl_exit:
+
+ %undef CMDSTR
+
+ mov esp, ebp
+ pop ebp
+ ret
+
