X-Git-Url: https://git.danieliu.xyz/?a=blobdiff_plain;f=sped.asm;h=859d386ed7635ab529e75a097091bd730c906abd;hb=f0c5604be9e918713786e0fdecd7efe1e3cea0ee;hp=6230c852604e4d959e9a909669573042e4b17b32;hpb=4c9d6b68e0b493e23969b79e96457b68cfed8895;p=sped.git

diff --git a/sped.asm b/sped.asm
index 6230c85..859d386 100644
--- a/sped.asm
+++ b/sped.asm
@@ -1,4 +1,10 @@
+; sped - the stupidly pointless editor
+; written by pinosaur
 
+global main
+extern printf
+
+; macros
 %macro write_str 2
     mov eax, 4
     mov ebx, 1
@@ -8,14 +14,168 @@
 %endmacro
 
 section .data
-    msg db "SPED - the stupidly pointless editor", 0x0a
-    len equ $ - msg
+    banner_str db `SPED - the stupidly pointless editor\n`, 0x00
+    readfile_str db `reading file %s\n`, 0x00
+    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
+    char_str db `read this char: %i\n`, 0x00
+    printfint_str db `int: %i\n`, 0x00
+
+section .bss
+    read_buf resb 64
 
 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
+    jmp _main_exit
+
+    _main_existing:
+    mov ebx, DWORD [ebp+_ARGV]
+    add ebx, 4
+    push DWORD [ebx]
+    ; push readfile_str
+    ; call printf
+
+    call readFile
+
+    mov eax, 0
+    jmp _main_exit
+
+    _main_exit:
+    %undef _ARGC
+    %undef _ARGV
+
+    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_HANDLE 4
+
+    push ebp
+    mov ebp, esp
+    
+    ; allocate vars
+    sub esp, 4
+    mov DWORD [ebp-FILE_HANDLE], 0x00
+
+    ; open existing file
+    mov eax, 5
+    mov ebx, [ebp+_FILE_NAME]
+    mov ecx, 0
+    mov edx, 0777
     int 0x80
+    mov [ebp-FILE_HANDLE], eax
+
+    ; check if file was open successfully
+    cmp eax, 0
+    jge _readFile_noerror
+    push eax
+    push wrongfile_str
+    call printf
+    jmp _readFile_exit
+
+    _readFile_noerror:
+    push DWORD [ebp-FILE_HANDLE]
+    call readLine 
+
+    jmp _readFile_exit
+
+    _readFile_exit:
+    ; close file
+    mov eax, 6
+    mov ebx, [ebp-FILE_HANDLE]
+    int 0x80
+
+    %undef _FILE_NAME
+    %undef FILE_HANDLE
+
+    mov esp, ebp
+    pop ebp
+    ret
+
+
+; reads a line until newline character is reached
+; args: file_handle
+; return:
+;   location to buffer
+;   contains eof
+readLine:
+    %define _FILE_HANDLE 8
+    %define CHAR_PTR 4
+
+    push ebp
+    mov ebp, esp
+
+    sub esp, 4
+    mov DWORD [ebp-CHAR_PTR], 0x00
+
+    _readLine_loop:
+    ; if buffer is full
+    cmp BYTE [ebp-CHAR_PTR], 64
+    jne _readLine_notfull
+    jmp _readLine_exit
+
+    _readLine_notfull:
+    ; read a single character
+    mov eax, 3
+    mov ebx, [ebp+_FILE_HANDLE]
+    mov ecx, read_buf
+    add ecx, [ebp-CHAR_PTR]
+    mov edx, 1
+    int 0x80
+
+    mov eax, 4
+    mov ebx, 1
+    mov ecx, read_buf
+    add ecx, [ebp-CHAR_PTR]
+    mov edx, 1
+    int 0x80
+
+    ; check for newline
+    mov eax, read_buf
+    add eax, [ebp-CHAR_PTR]
+    cmp DWORD [eax], 0x0a
+    je _readLine_exit
+    
+    ; check for eof
+    mov eax, read_buf
+    add eax, [ebp-CHAR_PTR]
+    cmp DWORD [eax], 0x05
+    je _readLine_exit
+
+    add DWORD [ebp-CHAR_PTR], 1
+
+    jmp _readLine_loop
+
+    _readLine_exit:
+
+    %undef _FILE_HANDLE
+    %undef CHAR_PTR
+
+    mov esp, ebp
+    pop ebp
+    ret
+