+; sped - the stupidly pointless editor
+; written by pinosaur
global main
extern printf
+extern malloc
+extern realloc
+extern free
+extern memset
; macros
%macro write_str 2
nofile_str db `no file provided\n`, 0x00
argcount_str db `there are %d args\n`, 0x00
wrongfile_str db `unable to open file, error code: %i\n`, 0x00
-
-; section .bss
+ char_str db `read this char: %i\n`, 0x00
+ printfint_str db `int: %i\n`, 0x00
section .text
main:
+ %define _ARGC 8
+ %define _ARGV 12
+
push ebp
mov ebp, esp
; read command line args
- mov ecx, [ebp+8]
+ mov ecx, [ebp+_ARGC]
cmp ecx, 1
- jg .main_existing
+ jg _main_existing
; display error msg if no file
push nofile_str
call printf
mov eax, 1
- jmp .main_exit
+ jmp _main_exit
-.main_existing:
- mov ebx, DWORD [ebp+12]
+ _main_existing:
+ mov ebx, DWORD [ebp+_ARGV]
add ebx, 4
push DWORD [ebx]
; push readfile_str
call readFile
mov eax, 0
- jmp .main_exit
+ jmp _main_exit
+
+ _main_exit:
+ %undef _ARGC
+ %undef _ARGV
-.main_exit:
mov esp, ebp
pop ebp
ret
+
; reads file line by line
; args: filename
; return:
; eax - pointer to mem
; ecx - lines read
readFile:
- %define _FILE_NAME 8
+ %define _FILE_NAME 8
%define FILE_HANDLE 4
+ %define IS_EOF 8
+ %define LINES_READ 12
+ %define BUF_PTR 16 ; malloced array of strings
push ebp
mov ebp, esp
; allocate vars
- sub esp, 4
+ sub esp, 16
mov DWORD [ebp-FILE_HANDLE], 0x00
-
+ mov DWORD [ebp-IS_EOF], 0x00
+ mov DWORD [ebp-LINES_READ], 0x00
+
+ push 0
+ call malloc
+ mov [ebp-BUF_PTR], eax
+
; open existing file
mov eax, 5
mov ebx, [ebp+_FILE_NAME]
mov ecx, 0
- mov edx, 0700
+ mov edx, 0777
int 0x80
mov [ebp-FILE_HANDLE], eax
; check if file was open successfully
cmp eax, 0
- jge .readFile_noerror
+ jge _readFile_loop
push eax
push wrongfile_str
call printf
- jmp .readFile_exit
+ jmp _readFile_exit
+
+ _readFile_loop:
+
+ ; check if eof was reached
+ cmp DWORD [ebp-IS_EOF], 1
+ je _readFile_exit
+
+ push DWORD [ebp-FILE_HANDLE]
+ call readLine
+
+ mov esi, eax
+ mov [ebp-IS_EOF], ebx
+
+ push esi
+ call printf
+
+ ; make string buffer bigger
+ mov eax, DWORD [ebp-LINES_READ]
+ add eax, 1
+ mov ecx, 4
+ mul ecx
+ push eax
+ push DWORD [ebp-BUF_PTR]
+ call realloc
+ mov DWORD [ebp-BUF_PTR], eax
-.readFile_noerror:
+ ; write string to buffer
+ mov eax, DWORD [ebp-BUF_PTR]
+ mov ecx, 4
+ mul ecx
+ mov eax, esi
- jmp .readFile_exit
+ add DWORD [ebp-LINES_READ], 1
-.readFile_exit:
+ jmp _readFile_loop
+ _readFile_exit:
; close file
mov eax, 6
mov ebx, [ebp-FILE_HANDLE]
%undef _FILE_NAME
%undef FILE_HANDLE
+ %undef IS_EOF
+ %undef LINES_READ
+ %undef BUF_PTR
mov esp, ebp
pop ebp
; reads a line until newline character is reached
; args: file_handle
-; return: location to buffer
+; return:
+; eax: location to buffer
+; ebx: contains eof
readLine:
-
%define _FILE_HANDLE 8
+ %define CHAR_COUNT 4 ; count number of characters read
+ %define BLOCK_COUNT 8 ; number of 64 blocks we've read
+ %define STR_PTR 12 ; malloced buffer to store read string
push ebp
mov ebp, esp
+
+ ; allocate vars
+ sub esp, 12
+ mov DWORD [ebp-CHAR_COUNT], 0x00
+ mov DWORD [ebp-BLOCK_COUNT], 0x00
+
+ push 64
+ call malloc
+ mov [ebp-STR_PTR], eax
+
+ push DWORD [ebp-STR_PTR]
+ push 0x00
+ push 64
-.readLine_loop:
+ _readLine_loop:
+ ; if buffer is full
+ cmp BYTE [ebp-CHAR_COUNT], 63 ; leave one byte for null byte
+ jne _readLine_notfull
+ jmp _readLine_exit
+ _readLine_notfull:
; read a single character
mov eax, 3
mov ebx, [ebp+_FILE_HANDLE]
- ; mov ecx,
+ mov ecx, [ebp-STR_PTR]
+ add ecx, [ebp-CHAR_COUNT]
mov edx, 1
int 0x80
- jmp .readLine_loop
+ ; mov eax, 4
+ ; mov ebx, 1
+ ; mov ecx, [ebp-STR_PTR]
+ ; add ecx, [ebp-CHAR_COUNT]
+ ; mov edx, 1
+ ; int 0x80
+
+ ; check for eof
+ cmp eax, 0 ; eax has zero on eof
+ jne _readLine_not_eof
+ mov ebx, 1
+ jmp _readLine_exit
+ _readLine_not_eof:
+
+ ; check for newline
+ mov eax, [ebp-STR_PTR]
+ add eax, [ebp-CHAR_COUNT]
+ cmp DWORD [eax], 0x0a
+ jne _readLine_not_newline
+ mov ebx, 0
+ jmp _readLine_exit
+ _readLine_not_newline:
+
+ add DWORD [ebp-CHAR_COUNT], 1
+ jmp _readLine_loop
+
+ _readLine_exit:
+
+ mov eax, DWORD [ebp-STR_PTR]
+
+ %undef _FILE_HANDLE
+ %undef CHAR_COUNT
+ %undef BLOCK_COUNT
+ %undef STR_PTR
mov esp, ebp
pop ebp
