Liren Large Software Subsidy 7

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Assembly Source File | 1987-10-29 | 11.1 KB | 435 lines

include PROGSEG.H ;---------------------------------------------------------------------------- ; c_reate(filename,attr) - creates a file ; char *filename - ptr to filename ; int attr - attributes to use for file ; ; returns file handle or -1 - error ; ;---------------------------------------------------------------------------- public c_reate c_reate proc near push bp mov bp,sp mov ax,03c00h mov dx,4[bp] ; get the file name mov cx,6[bp] ;get attributes of new file int 21h ; call dos jnc createx mov ax,-1 createx: mov sp,bp pop bp ret c_reate endp ;----------------------------------------------------------------------------- ; ; o_pen(filename,acc_code) ; char *filename - file name string ; int acc_code - 0 - file opened for reading ; 1 - file opened for writing ; 2 - file opened for read/write ; returns - file handle or error code ( see error table) ;---------------------------------------------------------------------------- public o_pen o_pen proc near push bp mov bp,sp mov dx,[bp+4] ;offset, small model ds points already mov al,[bp+6] ;access code r/w/w-r mov ah,03dh ; open a file int 21h jnc openex mov ax,-1 openex: mov sp,bp pop bp ret o_pen endp ;----------------------------------------------------------------------------- ; C_LOSE(fh) - closes a valid file handle ; int fh - file handle ; ; returns - 0 - successfull, -1 - invalid file handle ;----------------------------------------------------------------------------- public c_lose c_lose proc near push bp mov bp,sp mov bx,4[bp] ; get file handle mov ah,03eh ; service to close a file handle int 21h mov ax,00 jnc closex mov ax,-1 ; tell prog that error occurred closex: mov sp,bp pop bp ret c_lose endp ;--------------------------------------------------------------------------- ; _DEL(filename) - deletes a file from the directory ; ; char *filename - name of file to delete ; ; returns 0 - success or error code: 2 - file not found ; 5 - access denied ;---------------------------------------------------------------------------- public _del _del proc near push bp mov bp,sp mov dx,4[bp] mov ax,4100h int 21h jc delex mov ax,0 delex: mov sp,bp pop bp ret _del endp ;---------------------------------------------------------------------------- ; ; l_seek(fh,offset,method) ; int fh; file handle ; long offset; offset in file to seek to (from start of file) ; int method; - 0 - offset from beginning of file ; - 1 - offset from current position ; - 2 - from end of file ; ; Seek to a specific position in file. ; ;------------------------------------------------------------------------------ PUBLIC l_seek l_seek PROC NEAR push bp mov bp,sp ; Basically lseek(fh,offset,method) mov ah,42h mov bx,[bp+4] ;file handle mov cx,[bp+8] ;offset (most significant) mov dx,[bp+6] ; (least significant) mov al,[bp+10] ; get seek method int 21h seekex: mov sp,bp pop bp ret l_seek ENDP ;***************************************************************************** ; ; r_ead(fh,bp,bl) ; int fh; /* file handle */ ; char near *bp; /* memory loc to read to */ ; unsigned int bl; /* amount to read */ ; ; Read a buffer from the current location in file. ; ;***************************************************************************** PUBLIC r_ead r_ead PROC NEAR push bp mov bp,sp mov ah,3fh ;read file mov bx,[bp+4] ;file handle mov cx,[bp+8] ;bl (buffer length) mov dx,[bp+6] ;bp (buffer pointer) int 21h jnc readex mov ax,-1 ; error reading file readex: mov sp,bp pop bp ret r_ead ENDP ;***************************************************************************** ; ; w_rite(fh,bp,bl) ; int fh; /* file handle */ ; char near *bp; /* memory loc to read to */ ; unsigned int bl; /* amount to read */ ; ; Write a buffer to the current location in file. ; ;***************************************************************************** PUBLIC w_rite w_rite PROC NEAR push bp mov bp,sp push ds ;save current data seg mov ah,40h ;write file mov bx,[bp+4] ;file handle mov cx,[bp+8] ;bl(buffer length) mov dx,[bp+6] ;bp (buffer pointer) int 21h jnc writex ;jmp if no error mov ax,-1 ;tell caller error happened writex: mov sp,bp pop bp ret w_rite ENDP ;***************************************************************************** ; ; _setftime(fh,date,time) ; int fh; /* file handle */ ; unsigned int date; /* date to set on file */ ; unsigned int time; /* time to set on file */ ; ; Set the creation/revision date/time on a file. ; ;***************************************************************************** PUBLIC _setftime _setftime PROC NEAR push bp mov bp,sp mov ax,5701h ;set file date/time function mov bx,[bp+4] ;file handle mov cx,[bp+8] ;file time mov dx,[bp+6] ;file date int 21h mov sp,bp ;no error checking done pop bp ret _setftime ENDP ;----------------------------------------------------------------------------- ; ; _getcdir(drive,buffer) ; int drive; ; char *buffer; ; ; Get the current dir for given drive. ; ;------------------------------------------------------------------------------- PUBLIC _getcdir _getcdir PROC NEAR push bp mov bp,sp push si mov ah,47h ;get current dir mov dl,BYTE PTR [bp+4] ;drive code to DL mov si,[bp+6] ;buffer ptr to DS:SI mov BYTE PTR [si],0 ;make sure its terminated if error int 21h pop si mov sp,bp ;no error checking done pop bp ret _getcdir ENDP ;----------------------------------------------------------------------------- ; ; _chdir(dir_name) ; char *dir_name; /* name of directory to make current */ ; ; returns 0 - successfull, -1 - error ;------------------------------------------------------------------------------- PUBLIC _chdir _chdir PROC NEAR push bp mov bp,sp mov ah,3bh ;get current dir mov dx,4[bp] ; get offset to new dir name int 21h mov ax,0 jnc endset mov ax,-1 endset: mov sp,bp ;no error checking done pop bp ret _chdir ENDP ;----------------------------------------------------------------------------- ; _MKDIR(dir_name) - creates a new subdirectory ; ; char *dir_name - ptr to name of directory to create ; ; returns - 0 - successfull 3 - path not found ; 5 - access denied ;---------------------------------------------------------------------------- public _mkdir _mkdir proc near push bp mov bp,sp mov dx,4[bp] ; get ptr to dir to make mov ax,3900h int 21h ; call dos jc mkdirex ; keep error code in ax for return mov ax,00 ; no error mkdirex: mov sp,bp pop bp ret _mkdir endp ;----------------------------------------------------------------------------- ; _RD(dir_name) - removes a subdirectory ; ; char *dir_name - ptr to dir name to remove ; ; returns - 0 - successful or error code: 3 - path not found ; 5 - dir not empty or ; access denied ;------------------------------------------------------------------------------ public _rd _rd proc near push bp mov bp,sp mov dx,4[bp] ; get dir name to remove mov ax,03a00h int 21h jc rdex mov ax,0 rdex: mov sp,bp pop bp ret _rd endp ;----------------------------------------------------------------------------- ; ; _setattrib(fn,attrs) ; char *fn; /* file name */ ; unsigned int attrs; /* attributes to set */ ; ; Set the file attributes ; ;----------------------------------------------------------------------------- PUBLIC _setattrib _setattrib PROC NEAR push bp mov bp,sp mov ax,4301h ;CHMOD dos function mov cx,[bp+6] ;file attributes mov dx,[bp+4] ;file name int 21h mov sp,bp ;no error checking done pop bp ret _setattrib ENDP ;----------------------------------------------------------------------------- ; ; unsigned int _getattrib(fn) ; char *fn; /* file name */ ; ; get the file attributes ; returns attributes in ax ;----------------------------------------------------------------------------- PUBLIC _getattrib _getattrib PROC NEAR push bp mov bp,sp mov ax,4300h ;CHMOD dos function mov dx,[bp+4] ;file name int 21h mov ax,cx ; mov attributes to cx for return to C mov sp,bp ;no error checking done pop bp ret _getattrib endp include endpseg.h end