X-Git-Url: https://git.danieliu.xyz/?p=sped.git;a=blobdiff_plain;f=fileutils.asm;h=32dcef6fd579a9610fd45dc1a3f89cf9cabf2f60;hp=8596ff381ec87a8885bc3ac4f8cc8203fb2b4b2d;hb=HEAD;hpb=aab6303fb9c43a2d727774c25b3c50a4b1fcae8d

diff --git a/fileutils.asm b/fileutils.asm
index 8596ff3..32dcef6 100644
--- a/fileutils.asm
+++ b/fileutils.asm
@@ -1,15 +1,23 @@
+; sped - the stupidly pointless editor
+; written by pinosaur
+; fileutils.asm: file i/o
+
+%include "macros.S"
 
 extern printf
 extern malloc
 extern realloc
 extern free
 extern memset
+extern strlen
 
 global readFile
 global readLine
+global writeFile
 
 section .data
     wrongfile_str db `unable to open file, error code: %i\n`, 0x00
+    returnvalue_str db `system call return was %i\n`, 0x00
 
 section .text
 
@@ -56,18 +64,14 @@ readFile:
 
     _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
+
+    ; check if eof was reached
+    cmp DWORD [ebp-IS_EOF], 1
+    je _readFile_exit
 
     ; make string buffer bigger
     mov eax, DWORD [ebp-LINES_READ]
@@ -155,13 +159,6 @@ readLine:
     add ecx, [ebp-CHAR_COUNT]
     mov edx, 1
     int 0x80
-
-    ; 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
@@ -202,6 +199,83 @@ readLine:
     ret
 
 ; writes contents of string array into file
-; arg: filename, string array
-; writeFile:
+; arg: filename, string array, number of lines
+writeFile:
+
+    %define _FILE_NAME    16
+    %define _STR_ARR      12
+    %define _STR_ARR_LEN  8
+    %define FILE_HANDLE   4
+    %define LINES_WRITTEN 8
+
+    push ebp
+    mov ebp, esp
+
+    ; allocate vars
+    sub esp, 8
+    mov DWORD [ebp-FILE_HANDLE], 0x00
+    mov DWORD [ebp-LINES_WRITTEN], 0x00
+
+    ; open existing file
+    mov eax, 5
+    mov ebx, [ebp+_FILE_NAME]
+    mov ecx, 2
+    mov edx, 0777
+    int 0x80
+    mov [ebp-FILE_HANDLE], eax
+
+    ; check if file was open successfully
+    cmp eax, 0
+    jl _writeFile_error
+
+    ; truncate file
+    mov eax, 93
+    mov ebx, [ebp-FILE_HANDLE]
+    mov ecx, 1
+    int 0x80
+    
+    _writeFile_loop:
+
+    ; check if we are done writing
+    mov eax, [ebp+_STR_ARR_LEN]
+    cmp eax, [ebp-LINES_WRITTEN]
+    je _writeFile_exit
+
+    ; get length of string to write
+    str_offset [ebp+_STR_ARR], [ebp-LINES_WRITTEN]
+    mov esi, eax
+    push DWORD [esi]
+    call strlen
+
+    mov edx, eax
+    mov eax, 4
+    mov ebx, [ebp-FILE_HANDLE]    
+    mov ecx, [esi]
+    int 0x80
+
+    add DWORD [ebp-LINES_WRITTEN], 1
+
+    jmp _writeFile_loop
+
+    _writeFile_error:
+    push eax
+    push wrongfile_str
+    call printf
+    jmp _writeFile_exit
+
+    _writeFile_exit:
+
+    ; close file
+    mov eax, 6
+    mov ebx, [ebp-FILE_HANDLE]
+    int 0x80
+    
+    %undef _FILE_NAME
+    %undef _STR_ARR
+    %undef _STR_ARR_LEN
+    %undef FILE_HANDLE
+    
+    mov esp, ebp
+    pop ebp
+    ret