X-Git-Url: https://git.danieliu.xyz/?p=sped.git;a=blobdiff_plain;f=sped.asm;h=e0920a1712b6c5af80784a4995d2eb9073796ef2;hp=585697bf643d0a2d09f74a024aeda23b8271f264;hb=HEAD;hpb=2505d1841221648a72e768f23a5a475c8e1c01d1 diff --git a/sped.asm b/sped.asm index 585697b..e0920a1 100644 --- a/sped.asm +++ b/sped.asm @@ -1,46 +1,35 @@ ; sped - the stupidly pointless editor ; written by pinosaur +; sped.asm: main file -%include "fileutils.S" +%include "macros.S" -global main extern printf -extern fflush -extern stdout - -; macros -%macro write_str 2 - mov eax, 4 - mov ebx, 1 - mov ecx, %1 - mov edx, %2 - int 0x80 -%endmacro + +extern readFile +extern repl + +global main section .data banner_str db `SPED - the stupidly pointless editor\n`, 0x00 - nofile_str db `no file provided\n`, 0x00 - readlines_str db `opened file with %i lines\n`, 0x00 - prompt_str db `sped > `, 0x00 - invalidcmd_str db `invalid command\n`, 0x00 - invalidaddr_str db `invalid address\n`, 0x00 - charcount_str db `read %i chars\n`, 0x00 - currentline_str db `current line: %i\n`, 0x00 - echo_str db `%s`, 0x00 ; print strings without format exploit - -section .bss - buffer resb 4 - buffer_lines resb 4 - cur_line resb 4 + nofile_str db `no file provided.\n`, 0x00 + readlines_str db `opened file with %i lines.\n`, 0x00 section .text main: %define _ARGC 8 %define _ARGV 12 + %define BUFFER 4 + %define BUFFER_LINES 8 + %define BUFFER_FILENAME 12 + push ebp mov ebp, esp + sub esp, 12 + ; read command line args mov ecx, [ebp+_ARGC] cmp ecx, 1 @@ -55,151 +44,38 @@ main: _main_existing: mov ebx, DWORD [ebp+_ARGV] add ebx, 4 ; first user arg is filename - push DWORD [ebx] + mov ebx, [ebx] + mov [ebp-BUFFER_FILENAME], ebx + + push DWORD [ebp-BUFFER_FILENAME] call readFile - mov [buffer], eax - mov [buffer_lines], ecx - mov DWORD [cur_line], 0x00 + mov [ebp-BUFFER], eax + mov [ebp-BUFFER_LINES], ecx - push DWORD [buffer_lines] + push DWORD [ebp-BUFFER_LINES] push readlines_str call printf + push DWORD [ebp-BUFFER] + push DWORD [ebp-BUFFER_LINES] + push DWORD [ebp-BUFFER_FILENAME] call repl mov eax, 0 jmp _main_exit _main_exit: + + ; free string array + %undef _ARGC %undef _ARGV + %undef BUFFER + %undef BUFFER_LINES + %undef BUFFER_FILENAME 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_cmd - - ; 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: - - ; p prints current line - mov eax, DWORD [ebp-CMDSTR] - cmp BYTE [eax], 'p' - jne _repl_cmd_print_end - - mov eax, DWORD [cur_line] - mov ecx, 4 - mul ecx - add eax, [buffer] - push DWORD [eax] - push echo_str - call printf - jmp _repl_continue - _repl_cmd_print_end: - - ; n prints the current line number - mov eax, DWORD [ebp-CMDSTR] - cmp BYTE [eax], 'n' - jne _repl_cmd_number_end - - push DWORD [cur_line] - push currentline_str - call printf - - jmp _repl_continue - _repl_cmd_number_end: - - ; - goes to prev line - mov eax, DWORD [ebp-CMDSTR] - cmp BYTE [eax], '-' - jne _repl_cmd_decline_end - - ; make sure we are within bounds - mov eax, DWORD [cur_line] - sub eax, 1 - cmp eax, 0 - jl _repl_invalid_addr - - sub DWORD [cur_line], 1 - - jmp _repl_continue - _repl_cmd_decline_end: - - ; + goes to next line - mov eax, DWORD [ebp-CMDSTR] - cmp BYTE [eax], '+' - jne _repl_cmd_incline_end - - ; make sure we are within bounds - mov eax, DWORD [cur_line] - add eax, 1 - cmp eax, [buffer_lines] - jge _repl_invalid_addr - - add DWORD [cur_line], 1 - - jmp _repl_continue - _repl_cmd_incline_end: - - - jmp _repl_invalid_cmd - - ; some error messages - _repl_invalid_cmd: - push invalidcmd_str - call printf - jmp _repl_continue - - _repl_invalid_addr: - push invalidaddr_str - call printf - jmp _repl_continue - - _repl_continue: - jmp _repl_loop - - _repl_exit: - - %undef CMDSTR - - mov esp, ebp - pop ebp - ret -