diff options
author | Jörg Frings-Fürst <debian@jff-webhosting.net> | 2015-11-06 07:14:47 +0100 |
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committer | Jörg Frings-Fürst <debian@jff-webhosting.net> | 2015-11-06 07:14:47 +0100 |
commit | d479dd1aab1c1cb907932c6595b0ef33523fc797 (patch) | |
tree | ad7d454b9edaae3d8892d84cd8f8ef5c2697b79b /jpeg/jmemdosa.asm | |
parent | 9491825ddff7a294d1f49061bae7044e426aeb2e (diff) |
Imported Upstream version 1.8.3upstream/1.8.3
Diffstat (limited to 'jpeg/jmemdosa.asm')
-rwxr-xr-x | jpeg/jmemdosa.asm | 379 |
1 files changed, 0 insertions, 379 deletions
diff --git a/jpeg/jmemdosa.asm b/jpeg/jmemdosa.asm deleted file mode 100755 index ecd4372..0000000 --- a/jpeg/jmemdosa.asm +++ /dev/null @@ -1,379 +0,0 @@ -; -; jmemdosa.asm -; -; Copyright (C) 1992, Thomas G. Lane. -; This file is part of the Independent JPEG Group's software. -; For conditions of distribution and use, see the accompanying README file. -; -; This file contains low-level interface routines to support the MS-DOS -; backing store manager (jmemdos.c). Routines are provided to access disk -; files through direct DOS calls, and to access XMS and EMS drivers. -; -; This file should assemble with Microsoft's MASM or any compatible -; assembler (including Borland's Turbo Assembler). If you haven't got -; a compatible assembler, better fall back to jmemansi.c or jmemname.c. -; -; To minimize dependence on the C compiler's register usage conventions, -; we save and restore all 8086 registers, even though most compilers only -; require SI,DI,DS to be preserved. Also, we use only 16-bit-wide return -; values, which everybody returns in AX. -; -; Based on code contributed by Ge' Weijers. -; - -JMEMDOSA_TXT segment byte public 'CODE' - - assume cs:JMEMDOSA_TXT - - public _jdos_open - public _jdos_close - public _jdos_seek - public _jdos_read - public _jdos_write - public _jxms_getdriver - public _jxms_calldriver - public _jems_available - public _jems_calldriver - -; -; short far jdos_open (short far * handle, char far * filename) -; -; Create and open a temporary file -; -_jdos_open proc far - push bp ; linkage - mov bp,sp - push si ; save all registers for safety - push di - push bx - push cx - push dx - push es - push ds - mov cx,0 ; normal file attributes - lds dx,dword ptr [bp+10] ; get filename pointer - mov ah,3ch ; create file - int 21h - jc open_err ; if failed, return error code - lds bx,dword ptr [bp+6] ; get handle pointer - mov word ptr [bx],ax ; save the handle - xor ax,ax ; return zero for OK -open_err: pop ds ; restore registers and exit - pop es - pop dx - pop cx - pop bx - pop di - pop si - pop bp - ret -_jdos_open endp - - -; -; short far jdos_close (short handle) -; -; Close the file handle -; -_jdos_close proc far - push bp ; linkage - mov bp,sp - push si ; save all registers for safety - push di - push bx - push cx - push dx - push es - push ds - mov bx,word ptr [bp+6] ; file handle - mov ah,3eh ; close file - int 21h - jc close_err ; if failed, return error code - xor ax,ax ; return zero for OK -close_err: pop ds ; restore registers and exit - pop es - pop dx - pop cx - pop bx - pop di - pop si - pop bp - ret -_jdos_close endp - - -; -; short far jdos_seek (short handle, long offset) -; -; Set file position -; -_jdos_seek proc far - push bp ; linkage - mov bp,sp - push si ; save all registers for safety - push di - push bx - push cx - push dx - push es - push ds - mov bx,word ptr [bp+6] ; file handle - mov dx,word ptr [bp+8] ; LS offset - mov cx,word ptr [bp+10] ; MS offset - mov ax,4200h ; absolute seek - int 21h - jc seek_err ; if failed, return error code - xor ax,ax ; return zero for OK -seek_err: pop ds ; restore registers and exit - pop es - pop dx - pop cx - pop bx - pop di - pop si - pop bp - ret -_jdos_seek endp - - -; -; short far jdos_read (short handle, void far * buffer, unsigned short count) -; -; Read from file -; -_jdos_read proc far - push bp ; linkage - mov bp,sp - push si ; save all registers for safety - push di - push bx - push cx - push dx - push es - push ds - mov bx,word ptr [bp+6] ; file handle - lds dx,dword ptr [bp+8] ; buffer address - mov cx,word ptr [bp+12] ; number of bytes - mov ah,3fh ; read file - int 21h - jc read_err ; if failed, return error code - cmp ax,word ptr [bp+12] ; make sure all bytes were read - je read_ok - mov ax,1 ; else return 1 for not OK - jmp short read_err -read_ok: xor ax,ax ; return zero for OK -read_err: pop ds ; restore registers and exit - pop es - pop dx - pop cx - pop bx - pop di - pop si - pop bp - ret -_jdos_read endp - - -; -; short far jdos_write (short handle, void far * buffer, unsigned short count) -; -; Write to file -; -_jdos_write proc far - push bp ; linkage - mov bp,sp - push si ; save all registers for safety - push di - push bx - push cx - push dx - push es - push ds - mov bx,word ptr [bp+6] ; file handle - lds dx,dword ptr [bp+8] ; buffer address - mov cx,word ptr [bp+12] ; number of bytes - mov ah,40h ; write file - int 21h - jc write_err ; if failed, return error code - cmp ax,word ptr [bp+12] ; make sure all bytes written - je write_ok - mov ax,1 ; else return 1 for not OK - jmp short write_err -write_ok: xor ax,ax ; return zero for OK -write_err: pop ds ; restore registers and exit - pop es - pop dx - pop cx - pop bx - pop di - pop si - pop bp - ret -_jdos_write endp - - -; -; void far jxms_getdriver (XMSDRIVER far *) -; -; Get the address of the XMS driver, or NULL if not available -; -_jxms_getdriver proc far - push bp ; linkage - mov bp,sp - push si ; save all registers for safety - push di - push bx - push cx - push dx - push es - push ds - mov ax,4300h ; call multiplex interrupt with - int 2fh ; a magic cookie, hex 4300 - cmp al,80h ; AL should contain hex 80 - je xmsavail - xor dx,dx ; no XMS driver available - xor ax,ax ; return a nil pointer - jmp short xmsavail_done -xmsavail: mov ax,4310h ; fetch driver address with - int 2fh ; another magic cookie - mov dx,es ; copy address to dx:ax - mov ax,bx -xmsavail_done: les bx,dword ptr [bp+6] ; get pointer to return value - mov word ptr es:[bx],ax - mov word ptr es:[bx+2],dx - pop ds ; restore registers and exit - pop es - pop dx - pop cx - pop bx - pop di - pop si - pop bp - ret -_jxms_getdriver endp - - -; -; void far jxms_calldriver (XMSDRIVER, XMScontext far *) -; -; The XMScontext structure contains values for the AX,DX,BX,SI,DS registers. -; These are loaded, the XMS call is performed, and the new values of the -; AX,DX,BX registers are written back to the context structure. -; -_jxms_calldriver proc far - push bp ; linkage - mov bp,sp - push si ; save all registers for safety - push di - push bx - push cx - push dx - push es - push ds - les bx,dword ptr [bp+10] ; get XMScontext pointer - mov ax,word ptr es:[bx] ; load registers - mov dx,word ptr es:[bx+2] - mov si,word ptr es:[bx+6] - mov ds,word ptr es:[bx+8] - mov bx,word ptr es:[bx+4] - call dword ptr [bp+6] ; call the driver - mov cx,bx ; save returned BX for a sec - les bx,dword ptr [bp+10] ; get XMScontext pointer - mov word ptr es:[bx],ax ; put back ax,dx,bx - mov word ptr es:[bx+2],dx - mov word ptr es:[bx+4],cx - pop ds ; restore registers and exit - pop es - pop dx - pop cx - pop bx - pop di - pop si - pop bp - ret -_jxms_calldriver endp - - -; -; short far jems_available (void) -; -; Have we got an EMS driver? (this comes straight from the EMS 4.0 specs) -; -_jems_available proc far - push si ; save all registers for safety - push di - push bx - push cx - push dx - push es - push ds - mov ax,3567h ; get interrupt vector 67h - int 21h - push cs - pop ds - mov di,000ah ; check offs 10 in returned seg - lea si,ASCII_device_name ; against literal string - mov cx,8 - cld - repe cmpsb - jne no_ems - mov ax,1 ; match, it's there - jmp short avail_done -no_ems: xor ax,ax ; it's not there -avail_done: pop ds ; restore registers and exit - pop es - pop dx - pop cx - pop bx - pop di - pop si - ret - -ASCII_device_name db "EMMXXXX0" - -_jems_available endp - - -; -; void far jems_calldriver (EMScontext far *) -; -; The EMScontext structure contains values for the AX,DX,BX,SI,DS registers. -; These are loaded, the EMS trap is performed, and the new values of the -; AX,DX,BX registers are written back to the context structure. -; -_jems_calldriver proc far - push bp ; linkage - mov bp,sp - push si ; save all registers for safety - push di - push bx - push cx - push dx - push es - push ds - les bx,dword ptr [bp+6] ; get EMScontext pointer - mov ax,word ptr es:[bx] ; load registers - mov dx,word ptr es:[bx+2] - mov si,word ptr es:[bx+6] - mov ds,word ptr es:[bx+8] - mov bx,word ptr es:[bx+4] - int 67h ; call the EMS driver - mov cx,bx ; save returned BX for a sec - les bx,dword ptr [bp+6] ; get EMScontext pointer - mov word ptr es:[bx],ax ; put back ax,dx,bx - mov word ptr es:[bx+2],dx - mov word ptr es:[bx+4],cx - pop ds ; restore registers and exit - pop es - pop dx - pop cx - pop bx - pop di - pop si - pop bp - ret -_jems_calldriver endp - -JMEMDOSA_TXT ends - - end |