Cream of the Crop 21

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/ Cream of the Crop 21 / Cream of the Crop 21 (Terry Blount) (October 1996).iso / program / freeli22.zip / 386LIB1.ASX < prev next >

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Text File | 1996-09-01 | 95KB | 3,212 lines

~~~C_START Ideal Extrn main:near Public startup, exit Public TopByte, AtExitCnt Model Tiny CodeSeg P386 ;****************** startup() -- Start program Proc startup pushf ;Check for 386+ pushf pop ax xor ax,7000h push ax popf pushf pop bx popf cmp ax,bx je p0_badcpu mov ax,3001h ;Check for DOS 4.0 int 21h cmp al,4 jb p0_baddos mov ah,4Ah ;Modify memory allocation mov bx,1000h ;Keep first 64K int 21h ;DOS call mov sp,0FF00h ;Shift stack down 256 bytes mov ax,2523h ;Set null Ctrl-C handler mov dx,offset IntRet ;so that Ctrl-C can't int 21h ;abort the program mov ax,3500h ;Get current Int 0 handler int 21h ; (divide by zero) mov [word OldInt0],bx ;Save handler mov [word OldInt0+2],es push cs ;Restore ES pop es mov ax,2500h ;Set the divide by zero mov dx,offset DivZero ;handler: now it just int 21h ;ignores the error mov ax,0FB00h ;Initialize dynamic memory sub ax,offset TopByte ;leaving 768 bytes for the mov [word TopByte],ax ;stack (which is at 0FF00h) mov [byte TopByte+2],2 ;Initial block is free, last mov di,sp ;Parse arguments call ParseArgs call main ;Call main function push ax ;Terminate with return code call exit p0_baddos: push offset BadDosStr ;'Bad Dos' message jmp p0_error p0_badcpu: push offset BadCPUStr ;'Bad CPU' message p0_error: mov dx,offset BadStr ;Print first part mov ah,9 int 21h pop dx ;Print second part int 21h mov ax,4CFFh ;Return with error 255 int 21h EndP startup ;****************** DivZero -- Divide by zero handler Proc DivZero push bp ;Set up stack frame mov bp,sp pusha ;Save all registers push ds xor cx,cx ;CX = displacement mov ds,[bp+4] ;DS:BX = DIV instruction mov bx,[bp+2] cmp [byte bx],66h ;Skip past opsize, if any jne $+4 inc bx inc cx mov al,[bx+1] ;AL = AH = ModRM byte mov ah,al and al,0C0h ;Mask off mode bits cmp al,0C0h ;Mode = 11 (no disp)? je DZ_dis0 cmp al,040h ;Mode = 01 (1 byte disp)? je DZ_dis1 cmp al,080h ;Mode = 10 (2 byte disp)? je DZ_dis2 cmp ah,36h ;Mode = 00. No disp except jne DZ_dis0 ;if R/M = 110 (2 byte disp). DZ_dis2: inc cx ;2 byte displacement DZ_dis1: inc cx ;1 byte displacement DZ_dis0: inc cx ;Instruction is two bytes inc cx add [bp+2],cx ;Skip past instruction DZ_done: pop ds ;Restore registers popa pop bp ;Delete stack frame IntRet: iret ;Interrupt return EndP DivZero ;****************** Internal data OldInt0: ;Old divide-by-zero handler BadStr db 'Need at least $' ;OK to overwrite strings BadCPUStr db 'an 80386 CPU',13,10,'$' BadDosStr db 'DOS 4.0',13,10,'$' AtExitCnt dw 0 ;Exit function count AtExitTblO equ 0FF60h ;Exit function table offset ;****************** exit() -- Terminate program ;void exit(int retval); Proc exit mov ax,2500h ;Reset the default divide mov dx,[word OldInt0] ;by zero handler mov ds,[word OldInt0+2] int 21h push cs ;Restore DS pop ds mov cx,[AtExitCnt] ;CX = atexit count jcxz p1_done ;No exit functions? mov si,AtExitTblO ;SI = atexit table p1_loop: lodsw ;Get function call ax ;Call function loop p1_loop ;Loop back p1_done: pop ax ax ;Pop arg into AX mov ah,4Ch ;Terminate program int 21h ;DOS call EndP exit ;**************************** ParseArgs() -- internal: Parse arguments Proc ParseArgs ;Supply DI = 256-byte buffer, CS = DS = ES ;Returns CX = number of arguments ;the buffer will contain a list of ;near offsets to AsciiZ strings ;(and the strings themselves) pusha ;Save all registers mov bx,di ;BX = buffer mov cl,[80h] ;CX = length of command line xor ch,ch ;which is stored at 80h push cx ;Save CX mov si,81h ;SI = command line add di,80h ;DI = second half of buffer push di ;Save DI rep movsb ;Move command line out of DTA xor al,al ;Replace the CR at the end stosb ;with a null pop di cx ;Restore DI, length in CX inc cx ;Make length include last null xor dx,dx ;Zero argument counter mov al,' ' ;AL = space p2_loop: repe scasb ;Search for a non-space dec di inc cx cmp [byte di],0 ;Is it a null? je p2_done mov [bx],di ;Store offset in list inc bx ;Advance pointers inc bx inc dx repne scasb ;Search for a space mov [byte di-1],0 ;Replace it by a null jmp p2_loop ;Loop back p2_done: mov bp,sp ;Change pushed AX mov [bp+12],dx popa ;Restore registers ret ;Return EndP ParseArgs UDataSeg ;Uninit. data seg: dummy Label TopByte ;Top byte of code (start of heap) End ~~~C_ATEXIT Ideal Extrn AtExitCnt:word Public atexit Model Tiny CodeSeg P386 AtExitTblO equ 0FF60h ;Exit function table offset ;****************** atexit() -- Add exit function ;int atexit(void *func); func equ bp+4 Proc atexit push bp ;Set up stack frame mov bp,sp push bx ;Save BX cmp [word AtExitCnt],16 ;16 functions max jae p2_error mov bx,[AtExitCnt] ;BX = offset add bx,bx mov ax,[func] ;AX = function mov [AtExitTblO+bx],ax ;Add function to table inc [word AtExitCnt] ;Increment count p2_done: pop bx ;Restore BX pop bp ;Delete stack frame ret 2 ;Return p2_error: xor ax,ax ;Return 0: failure jmp p2_done EndP atexit End ~~~C_PUTCHR Ideal Public PUT_CHAR Model Tiny CodeSeg P386 ;****************** PUT_CHAR -- Like Int 29h but with redirection. ; Takes AL = char. Proc PUT_CHAR pusha ;Save registers xchg dx,ax ;STDOUT output, DL = char mov ah,2 int 21h ;DOS call popa ;Restore registers ret ;Return EndP PUT_CHAR End ~~~C_FILES Ideal Public fopen,fclose,fsetbuf Model Tiny CodeSeg P386 ;****************** File Structure . . . ; Offset Size Description ; 0 Word File handle ; 2 Word File mode ; 4 Dword Buffer position in file ; 8 Word Buffer pointer position ; 10 Word Number of bytes in buffer ; 12 Word Size of buffer (N) ; 14 Word Signature 'FI' ; 16 N bytes File buffer BUF_SIZ dw 1024 ;Buffer size (default 1K) F_MODES db 00h,01h ;0 = open for read db 02h,11h ;1 = open/create for read/write db 02h,01h ;2 = open for read/write db 02h,12h ;3 = create/truncate for read/write db 02h,10h ;4 = create for read/write db 6 dup(0) ;Fail for 5, 6, 7 ;****************** fopen() -- Open a buffered file ;int fopen(char *fname, int mode); fname = bp+6 mode = bp+4 Proc fopen push bp ;Set up stack frame mov bp,sp push ds si bx cx dx ;Save registers mov bx,[mode] ;BX = mode and bx,7 ;Mode mod 8 add bx,bx movzx dx,[F_MODES+bx+1] ;BX:DX = DOS mode movzx bx,[F_MODES+bx] mov ax,6C00h ;Extended open file xor cx,cx ;Normal attribute mov si,[fname] ;SI = name int 21h ;DOS call jc p1_err1 ;Check for errors xchg dx,ax ;DX = handle mov ah,48h ;Allocate memory mov bx,[BUF_SIZ] ;BX = num. of paras shr bx,4 ; = (BUF_SIZ / 16) + 1 inc bx int 21h ;DOS call jc p1_err2 ;Check for errors mov ds,ax ;DS = segment mov [word 0],dx ;[word 0] = handle mov cx,[mode] mov [word 2],cx ;[word 2] = mode xor bx,bx mov [word 4],bx ;[dword 4] = buffer position mov [word 6],bx mov [word 8],bx ;[word 8] = buffer pointer mov bx,[cs:BUF_SIZ] mov [word 12],bx ;[word 12] = buffer size mov [word 14],'FI' ;[word 14] = 'FI': signature mov bx,dx ;BX = handle mov ah,3Fh ;Read file mov cx,[cs:BUF_SIZ] ;BUF_SIZ bytes mov dx,16 ;Buffer offset int 21h ;DOS call mov [word 10],ax ;Set byte count mov ax,ds ;AX = segment p1_done: pop dx cx bx si ds ;Restore registers pop bp ;Delete stack frame ret 4 ;Return p1_err2: mov ah,3Eh ;Out of memory, close file mov bx,dx ;BX = handle int 21h ;DOS call p1_err1: xor ax,ax ;Error, return 0 jmp p1_done EndP fopen ;****************** fclose() -- Close a buffered file ;void fclose(int fptr); fptr = bp+4 Proc fclose push bp ;Set up stack frame mov bp,sp push ds es ;Save registers pusha mov ds,[fptr] ;DS = seg of file cmp [word 14],'FI' ;Check for signature jne p2_done mov bx,[word 0] ;BX = handle cmp [byte 2],0 ;Read only, can't write buffer je p2_skip mov ax,4200h ;Move file ptr mov cx,[word 6] ;CX:DX = buffer pos mov dx,[word 4] int 21h ;DOS call mov ah,40h ;Write file mov cx,[word 10] ;CX = bytes mov dx,16 ;Buffer offset int 21h ;DOS call p2_skip: mov ah,3Eh ;Close file int 21h ;DOS call mov ah,49h ;Free memory push ds ;ES = segment pop es int 21h ;DOS call p2_done: popa ;Restore registers pop es ds pop bp ;Delete stack frame ret 2 ;Return EndP fclose ;****************** fsetbuf() -- Set buffer size (for future use) ;int fsetbuf(int bsize); bsize = bp+4 Proc fsetbuf push bp ;Set up stack frame mov bp,sp mov ax,[bsize] ;AX = size and ax,7FF0h ;Put it in range cmp ax,128 jb $+5 mov ax,128 mov [BUF_SIZ],ax ;Set buffer size pop bp ;Delete stack frame ret 2 ;Return EndP fsetbuf End ~~~C_FPUTC Ideal Public fputc Model Tiny CodeSeg P386 ;****************** fputc() -- Put char to buffered file ;int fputc(int fptr, int chr); fptr = bp+6 chr = bp+4 Proc fputc push bp ;Set up stack frame mov bp,sp push ds si bx cx dx ;Save registers mov ds,[fptr] ;DS = seg of file cmp [word 14],'FI' ;Check for signature jne p1_error mov bx,[word 0] ;BX = handle cmp [word 2],0 ;Read only, can't put char je p1_error mov si,[word 8] ;SI = pointer pos cmp si,[word 12] ;Filled buffer? jb p1_write ;Jump if not mov ax,4200h ;Move file ptr mov cx,[word 6] ;CX:DX = buffer pos mov dx,[word 4] int 21h ;DOS call mov ah,40h ;Write file mov cx,[word 12] ;CX = bytes mov dx,16 ;Buffer offset int 21h ;DOS call mov ah,3Fh ;Read file, same data... int 21h ;DOS call mov [word 10],ax ;Set byte count xor si,si add [word 4],cx ;Advance buffer position adc [word 6],si mov [word 8],si ;Pointer pos = 0 p1_write: mov al,[chr] ;AX = char xor ah,ah mov [16+si],al ;Put char in buffer inc si ;Advance pointer mov [word 8],si cmp si,[word 10] ;Hit last byte? jna p1_done inc [word 10] ;Advance byte count p1_done: pop dx cx bx si ds ;Restore registers pop bp ;Delete stack frame ret 4 ;Return p1_error: mov ax,-1 ;Error, return EOF jmp p1_done EndP fputc End ~~~C_FGETC Ideal Public fgetc Model Tiny CodeSeg P386 ;****************** fgetc() -- Get char from buffered file ;int fgetc(int fptr); fptr = bp+4 Proc fgetc push bp ;Set up stack frame mov bp,sp push ds si bx cx dx ;Save registers mov ds,[fptr] ;DS = seg of file cmp [word 14],'FI' ;Check for signature jne p1_error mov bx,[word 0] ;BX = handle mov si,[word 8] ;SI = pointer pos mov cx,[word 12] ;CX = buffer size cmp si,cx ;End of buffer? jb p1_read ;Jump if not xor si,si add [word 4],cx ;Advance buffer position adc [word 6],si mov [word 2],si ;Pointer pos = 0 mov ax,4200h ;Move file ptr mov cx,[word 6] ;CX:DX = buffer pos mov dx,[word 4] int 21h ;DOS call mov ah,3Fh ;Read file mov cx,[word 12] ;CX = bytes mov dx,16 ;Buffer offset int 21h ;DOS call mov [word 10],ax ;Set byte count p1_read: cmp si,[word 10] ;Hit last byte? jae p1_error mov al,[16+si] ;Get char from buffer xor ah,ah inc si ;Advance pointer mov [word 8],si p1_done: pop dx cx bx si ds ;Restore registers pop bp ;Delete stack frame ret 2 ;Return p1_error: mov ax,-1 ;Error, return EOF jmp p1_done EndP fgetc End ~~~C_FSEEK Ideal Public fseek,ftell Model Tiny CodeSeg P386 ;****************** fseek() -- Seek to position in buffered file ;int fseek(int fptr, long pos, int cmd); fptr = bp+10 pos = bp+6 cmd = bp+4 Proc fseek push bp ;Set up stack frame mov bp,sp push ds bx cx dx ;Save registers mov ds,[fptr] ;DS = seg of file cmp [word 14],'FI' ;Check for signature jne p1_error mov bx,[word 0] ;BX = handle cmp [word 2],0 ;Read only, can't write buffer je p1_seek mov ax,4200h ;Move file ptr mov cx,[word 6] ;CX:DX = buffer pos mov dx,[word 4] int 21h ;DOS call mov ah,40h ;Write file mov cx,[word 10] ;CX = bytes mov dx,16 ;Buffer offset int 21h ;DOS call p1_seek: mov ax,4200h ;Move file ptr mov cx,[word 6] ;CX:DX = current pos mov dx,[word 4] ; = buffer pos + pointer add dx,[word 8] adc cx,0 int 21h ;DOS call mov ah,42h ;Move file ptr mov al,[cmd] ;AL = command mov cx,[pos+2] ;CX:DX = new pos mov dx,[pos] int 21h ;DOS call mov [word 6],dx ;Save position mov [word 4],ax mov ah,3Fh ;Read file mov cx,[word 12] ;CX = bytes mov dx,16 ;Buffer offset int 21h ;DOS call mov [word 10],ax ;Set byte count mov [word 8],0 ;Pointer = 0 mov ax,1 ;return 1: success p1_done: pop dx cx bx ds ;Restore registers pop bp ;Delete stack frame ret 8 ;Return p1_error: xor ax,ax ;Error, return 0 jmp p1_done EndP fseek ;****************** ftell() -- Return pointer in buffered file ;long ftell(int fptr); fptr = bp+4 Proc ftell push bp ;Set up stack frame mov bp,sp push ds ;Save registers mov ds,[fptr] ;DS = seg of file cmp [word 14],'FI' ;Check for signature jne p2_error mov dx,[word 6] ;DX:AX = current pos mov ax,[word 4] ; = buffer pos + pointer add ax,[word 8] adc dx,0 p2_done: pop ds ;Restore registers pop bp ;Delete stack frame ret 2 ;Return p2_error: xor ax,ax ;Error, return 0 xor dx,dx jmp p2_done EndP ftell End ~~~C_FREAD Ideal Extrn fgetc:near Public fread Model Tiny CodeSeg P386 ;****************** fread() -- Read block from buffered file ;int fread(int fptr, int nbytes, void *buf); fptr = bp+8 nbytes = bp+6 buf = bp+4 Proc fread push bp ;Set up stack frame mov bp,sp push bx cx di ;Save registers mov bx,[fptr] ;BX = file ptr mov cx,[nbytes] ;CX = num. of bytes mov di,[buf] ;DI = buffer ptr jcxz p1_done ;Zero bytes, do nothing p1_loop: push bx ;Get char call fgetc test ax,ax ;Check for errors jl p1_done mov [di],al ;Store byte inc di loop p1_loop ;Loop back p1_done: sub di,[buf] ;AX = byte count xchg ax,di pop di cx bx ;Restore registers pop bp ;Delete stack frame ret 6 ;Return EndP fread End ~~~C_FWRITE Ideal Extrn fputc:near Public fwrite Model Tiny CodeSeg P386 ;****************** fwrite() -- Write block to buffered file ;int fwrite(int fptr, int nbytes, void *buf); fptr = bp+8 nbytes = bp+6 buf = bp+4 Proc fwrite push bp ;Set up stack frame mov bp,sp push bx cx si ;Save registers mov bx,[fptr] ;BX = file ptr mov cx,[nbytes] ;CX = num. of bytes mov si,[buf] ;SI = buffer ptr mov ax,1 ;Fixup for zero check jcxz p1_done ;Zero bytes, do nothing p1_loop: lodsb ;Load byte push bx ax ;Write char call fputc test ax,ax ;Check for errors jl p1_done loop p1_loop ;Loop back p1_done: sub si,[buf] ;AX = byte count dec ax ;Subtract 1 if error sbb si,0 xchg ax,si pop si cx bx ;Restore registers pop bp ;Delete stack frame ret 6 ;Return EndP fwrite End ~~~C_FTRUNC Ideal Public ftrunc Model Tiny CodeSeg P386 ;****************** ftrunc() -- Truncate buffered file at current position ;int ftrunc(int fptr); fptr = bp+4 Proc ftrunc push bp ;Set up stack frame mov bp,sp push ds bx cx dx ;Save registers mov ds,[fptr] ;DS = seg of file cmp [word 14],'FI' ;Check for signature jne p1_error cmp [word 2],0 ;Read only, can't truncate je p1_error mov bx,[word 0] ;BX = handle mov ax,4200h ;Move file ptr mov cx,[word 6] ;CX:DX = current pos mov dx,[word 4] ; = buffer pos + pointer add dx,[word 8] adc cx,0 int 21h ;DOS call mov ah,40h ;Write 0 bytes to file xor cx,cx ;this truncates the file int 21h mov ax,[word 8] ;Now, byte count = pointer + 1 inc ax mov [word 10],ax mov ax,1 ;return 1: success p1_done: pop dx cx bx ds ;Restore registers pop bp ;Delete stack frame ret 2 ;Return p1_error: xor ax,ax ;Error, return 0 jmp p1_done EndP ftrunc End ~~~C_DELMOV Ideal Public fdel,fmove Model Tiny CodeSeg P386 ;****************** fdel() -- Delete a file ;int fdel(char *strp); strp equ bp+4 Proc fdel push bp ;Set up stack frame mov bp,sp push dx ;Save DX mov ah,41h ;Delete file mov dx,[strp] ;DX = string pointer int 21h ;DOS call sbb ax,ax ;AX = 1 if ok, 0 if error inc ax pop dx ;Restore DX pop bp ;Delete stack frame ret 2 ;Return EndP fdel ;****************** fmove() -- Move and/or rename a file ;int fmove(char *str1, char *str2); str1 equ bp+6 str2 equ bp+4 Proc fmove push bp ;Set up stack frame mov bp,sp push es dx di ;Save registers mov ah,56h ;Move file mov dx,[str1] ;DX = old name push ds ;ES = DS pop es mov di,[str2] ;ES:DI = new name int 21h ;DOS call sbb ax,ax ;AX = 1 if ok, 0 if error inc ax pop di dx es ;Restore registers pop bp ;Delete stack frame ret 4 ;Return EndP fmove End ~~~C_DIRECT Ideal Public getdir,setdir,mkdir,rmdir Model Tiny CodeSeg P386 ;****************** getdir() -- Get current directory ;void getdir(char *strp); strp equ bp+4 Proc getdir push bp ;Set up stack frame mov bp,sp pusha ;Save registers mov ah,19h ;Get current drive int 21h ;DOS call mov dl,al ;DL = drive mov ah,47h ;Get current directory mov si,[strp] ;SI = string pointer mov [byte si],'\' ;Add leading slash inc si int 21h ;DOS call popa ;Restore registers pop bp ;Delete stack frame ret 2 ;Return EndP getdir ;****************** DIRcall -- Internal: used by setdir,mkdir,rmdir ;void DIRcall(void); strp equ bp+4 Proc DIRcall push dx ;Save DX mov dx,[strp] ;DX = string pointer int 21h ;DOS call sbb ax,ax ;AX = 1 if ok, 0 if error inc ax pop dx ;Restore DX ret ;Return EndP DIRcall ;****************** setdir() -- Set current directory ;int setdir(char *strp); strp equ bp+4 Proc setdir push bp ;Set up stack frame mov bp,sp mov ah,3Bh ;Set current directory call DIRcall ;Directory call pop bp ;Delete stack frame ret 2 ;Return EndP setdir ;****************** mkdir() -- Create a directory ;int mkdir(char *strp); strp equ bp+4 Proc mkdir push bp ;Set up stack frame mov bp,sp mov ah,39h ;Create directory call DIRcall ;Directory call pop bp ;Delete stack frame ret 2 ;Return EndP mkdir ;****************** rmdir() -- Remove a directory ;int rmdir(char *strp); strp equ bp+4 Proc rmdir push bp ;Set up stack frame mov bp,sp mov ah,3Ah ;Remove directory call DIRcall ;Directory call pop bp ;Delete stack frame ret 2 ;Return EndP rmdir End ~~~C_DRIVE Ideal Public getdrive,setdrive Model Tiny CodeSeg P386 ;****************** getdrive() -- Get current drive ;int getdrive(void); Proc getdrive mov ah,19h ;Get current drive int 21h xor ah,ah ;Zero AH ret ;Return EndP getdrive ;****************** setdrive() -- set current drive ;void setdrive(int drnum); drnum equ bp+4 Proc setdrive push bp ;Set up stack frame mov bp,sp pusha ;Save registers mov ah,0Eh ;Set current drive mov dl,[drnum] ;DL = drive number int 21h popa ;Restore registers pop bp ;Delete stack frame ret 2 ;Return EndP setdrive End ~~~C_DFREE Ideal Public getdfree Model Tiny CodeSeg P386 ;****************** getdfree() -- Return amount of free disk space ;long getdfree(int drive); drive equ bp+4 Proc getdfree push bp ;Set up stack frame mov bp,sp push bx cx ;Save registers mov dl,[drive] ;DL = drive mov ah,36h ;Get free disk space int 21h cwd ;DX:AX = AX cmp ax,-1 ;Invalid, return -1 je p1_done mul cx ;DX:AX = free disk space mul bx ; = bytes/sector * sectors/a-unit ; * free a-units (allocation units) p1_done: pop cx bx ;Restore registers pop bp ;Delete stack frame ret ;Return EndP getdfree End ~~~C_EXEC Ideal Extrn allocmem:near,freemem:near Public exec Model Tiny CodeSeg P386 ;****************** exec() -- Execute program ;int exec(char *prog, char *cmdline); prog equ bp+6 cmdline equ bp+4 Proc exec push bp ;Set up stack frame mov bp,sp push ds es ;Save all registers pusha push 128 ;Allocate memory for call allocmem ;the cmdline buffer test ax,ax ;Out of memory? je p1_done xchg bx,ax ;Pointer in BX mov si,[prog] ;SI = program specification p1_loop1: lodsb ;Skip past initial spaces cmp al,' ' je p1_loop1 dec si push si ;Save prog string offset mov si,[cmdline] ;SI = command line mov di,bx ;DI = string buffer inc di mov cx,126 ;CX = 126 p1_loop3: lodsb ;Copy the string and test al,al ;count the chars je p1_cont stosb loop p1_loop3 p1_cont: neg cx ;CX = char count add cx,126 mov [bx],cl ;Store count mov al,13 ;Store a CR stosb mov ax,[2Eh] ;word 0 = environment mov [ParBlock],ax mov [ParBlock+2],bx ;word 2 = command line mov [ParBlock+4],cs ;word 4 = CS mov [ParBlock+6],5Ch ;word 6 = 5Ch mov [ParBlock+8],cs ;word 8 = CS mov [ParBlock+10],6Ch ;word 10 = 6Ch mov [ParBlock+12],cs ;word 12 = CS push bx ;Save memory pointer push ds ;ES:BX = parameter block pop es mov bx,offset ParBlock pop dx ;DX = program specification mov ax,4B00h ;DOS EXEC function mov [StackBuf],sp ;Save stack pointer mov [StackBuf+2],ss int 21h ;Execute program lss sp,[dword cs:StackBuf] ;Restore stack pointer sbb ax,ax ;AX = 1 if ok, 0 if error inc ax call freemem ;Free the memory (BX is still pushed) p1_done: mov es,ax ;Save AX in ES popa ;Restore general registers mov ax,es ;Restore AX pop es ds ;Restore segment registers pop bp ;Delete stack frame ret 4 ;Return StackBuf dw 0,0 ;Save area for SS:SP ParBlock dw 7 dup(0) ;EXEC parameter block EndP exec End ~~~C_BITIO Ideal Extrn fopen:near,fclose:near,fgetc:near,fputc:near Public bfopen, bfclose, putbit, getbit Public putbits, getbits, putcode, getcode Model Tiny P386 CodeSeg ;****************** Bit-File Structure . . . ; Offset Size Description ; 0 Word File handle ; 2 Word File mode ; 4 Byte Bit buffer ; 5 Byte Bit mask ;****************** bfopen() -- Open bit-file (returns bit handle) ; Modes: 0 = read, 1 = write ;int bfopen(char *fname, int mode); fname equ bp+6 mode equ bp+4 Proc bfopen push bp ;Set up stack frame mov bp,sp push ds bx cx dx ;Save registers mov bx,[mode] ;BX = mode and bx,1 mov cx,bx ;Save mode imul bx,3 ;Mode for fopen() push [word fname] bx ;Open the file call fopen test ax,ax ;Check for errors jz p1_err1 xchg dx,ax ;DX = file mov ah,48h ;Allocate memory mov bx,1 ;16 bytes int 21h ;DOS call jc p1_err2 ;Check for errors mov ds,ax ;DS = bit-file mov [0],dx ;Set file handle... mov [2],cx ;file mode... mov [word 4],8000h ;buffer/mask... p1_done: pop dx cx bx ds ;Restore registers pop bp ;Delete stack frame ret 4 ;Return p1_err2: push dx ;Out of memory, close file call fclose p1_err1: xor ax,ax ;Error, return 0 jmp p1_done EndP bfopen ;****************** bfclose() -- Close bit-file ;void bfclose(int bfp); bfp equ bp+4 Proc bfclose push bp ;Set up stack frame mov bp,sp pusha ;Save all registers push es mov es,[bfp] ;ES = bit-file cmp [word es:2],1 ;Input file? jne p2_skip cmp [byte es:5],80h ;Buffer empty? je p2_skip push [word es:0] ;Flush buffer push [word es:4] call fputc p2_skip: push [word es:0] ;Close file call fclose mov ah,49h ;Free memory int 21h pop es ;Restore registers popa pop bp ;Delete stack frame ret 2 ;Return EndP bfclose ;****************** getbit() -- Get bit from bit-file ;int getbit(int bfp); bfp equ bp+4 Proc getbit push bp ;Set up stack frame mov bp,sp push es ;Save registers mov es,[bfp] ;ES = bit-file cmp [word es:2],0 ;Output file, can't input jne p3_done cmp [byte es:5],80h ;Buffer empty? jne p3_skip1 push [word es:0] ;Get char call fgetc mov [es:4],al ;Save char p3_skip1: mov al,[es:4] ;Get bit and al,[es:5] shr [byte es:5],1 ;Move to next bit jnz p3_skip2 ;Finished a byte? mov [byte es:5],80h ;Set mask to 80h p3_skip2: test al,al ;AX = 1 if nonzero, setnz al ;or 0 if zero cbw p3_done: pop es ;Restore registers pop bp ;Delete stack frame ret 2 ;Return EndP getbit ;****************** putbit() -- Put bit to bit-file ;void putbit(int bfp, int bit); bfp equ bp+6 bit equ bp+4 Proc putbit push bp ;Set up stack frame mov bp,sp pusha ;Save all registers push es mov es,[bfp] ;ES = bit-file cmp [word es:2],1 ;Input file, can't output jne p4_done cmp [word bit],0 ;Check bit jz p4_skip mov al,[es:5] ;Add bit to buffer or [es:4],al p4_skip: shr [byte es:5],1 ;Move to next bit jnz p4_done ;Finished a byte? push [word es:0] ;Put byte to file push [word es:4] call fputc mov [word es:4],8000h ;Buf = 0, Mask = 80h p4_done: pop es ;Restore registers popa pop bp ;Delete stack frame ret 4 ;Return EndP putbit ;****************** getbits() -- Get bits from bit-file ;int getbits(int bfp, int count); bfp equ bp+6 count equ bp+4 Proc getbits push bp ;Set up stack frame mov bp,sp push es cx dx ;Save registers mov es,[bfp] ;ES = bit-file cmp [word es:2],0 ;Output file, can't input jne p5_done mov cx,[count] ;CX = bit count xor dx,dx ;Zero buffer p5_loop: cmp [byte es:5],80h ;Buffer empty? jne p5_skip1 push [word es:0] ;Get char call fgetc mov [es:4],al ;Save char p5_skip1: mov al,[es:4] ;Get bit and al,[es:5] ror [byte es:5],1 ;Move to next bit p5_skip2: add dx,dx ;Shift over test al,al ;If bit = 1, jz $+3 ;then add it in inc dx loop p5_loop ;Loop back xchg ax,dx ;AX = result p5_done: pop dx cx es ;Restore registers pop bp ;Delete stack frame ret 4 ;Return EndP getbits ;****************** putbits() -- Put bits to bit-file ;int putbits(int bfp, int code, int count); bfp equ bp+8 code equ bp+6 count equ bp+4 Proc putbits push bp ;Set up stack frame mov bp,sp pusha ;Save all registers mov bx,[bfp] ;BX = bit-file mov cx,[count] ;CX = bit count mov dx,[code] ;DX = code ror dx,cl ;Put at left p6_loop: add dx,dx ;Shift out bit sbb ax,ax ;AX = bit push bx ax ;Put bit call putbit loop p6_loop ;Loop back popa ;Restore registers pop bp ;Delete stack frame ret 6 ;Return EndP putbits ;****************** getcode() -- Get optimal code from bit-file ;int getcode(int bfp, int max); 'max' is number of possible codes bfp equ bp+6 max equ bp+4 Proc getcode push bp ;Set up stack frame mov bp,sp push bx cx dx si ;Save registers bsr cx,[max] ;CX = log2(max) + 1; jz p7_done ;Quit on 0 mov si,1 ;SI = 2^CX - max shl si,cl sub si,[max] mov bx,[bfp] ;BX = bit-file dec cx ;CX = count (log2(max)) push bx cx ;Get bits call getbits xchg ax,dx ;Result in DX cmp dx,si ;DX >= SI? jb p7_done push bx ;Add in another bit call getbit add dx,dx add dx,ax sub dx,si ;Subtract out SI p7_done: xchg ax,dx ;AX = result pop si dx cx bx ;Restore registers pop bp ;Delete stack frame ret 4 ;Return EndP getcode ;****************** putcode() -- Put optimal code to bit-file ; 'max' is number of possible codes ;int putcode(int bfp, int code, int max); bfp equ bp+8 code equ bp+6 max equ bp+4 Proc putcode push bp ;Set up stack frame mov bp,sp pusha ;Save all registers bsr cx,[max] ;CX = log2(max) + 1; jz p7_done ;Quit on 0 mov si,1 ;SI = 2^CX - max shl si,cl sub si,[max] mov dx,[code] ;DX = code dec cx ;CX = bit count cmp dx,si ;DX >= SI? jb p8_skip inc cx ;One more bit add dx,si ;and add in SI p8_skip: push [word bfp] dx cx ;Output bit code call putbits p8_done: popa ;Restore registers pop bp ;Delete stack frame ret 4 ;Return EndP putcode End ~~~C_MEMORY Ideal Extrn TopByte:Word Public allocmem,freemem,getmfree Model Tiny P386 CodeSeg ;****************** allocmem() -- Allocate memory ;void *allocmem(unsigned nbytes); nbytes equ bp+4 Proc allocmem push bp ;Set up stack frame mov bp,sp pusha ;Save registers push es mov dx,[bp+4] ;DX = num. of bytes + 3 add dx,3 mov bx,offset TopByte ;BX = first MCB p1_loop: mov cl,[bx+2] ;CX = flag byte test cl,1 ;Not free, loop jnz p1_lb mov ax,[bx] ;AX = size cmp ax,dx ;Big enough? jae p1_gotit p1_lb: test cl,2 ;Last block? jnz p1_nope ;Out of memory add bx,[bx] ;Next block jmp p1_loop ;Loop back p1_gotit: sub ax,3 ;Check for snug fit, cmp ax,dx ;that is, too little jbe p1_snug ;excess to split it sub ax,dx ;AX = excess add ax,3 mov si,bx ;SI = split point add si,dx mov [si],ax ;Set size of excess block mov [si+2],cl ;Set flags to original values mov [bx],dx ;Set size of present block mov [byte bx+2],1 ;Set flags: allocated, not last jmp p1_finish p1_snug: or [byte bx+2],1 ;Set allocated flag p1_finish: add bx,3 ;BX = offset of memory block p1_done: mov [bp-2],bx ;Change pushed AX pop es ;Restore registers popa pop bp ;Delete stack frame ret 2 ;Return p1_nope: xor bx,bx ;Return null pointer jmp p1_done EndP allocmem ;****************** freemem() -- Free memory ;void freemem(void *ptr); ptr equ bp+4 Proc freemem push bp ;Set up stack frame mov bp,sp pusha ;Save registers mov dx,[ptr] ;DX = pointer sub dx,3 ;Point to MCB mov bx,offset TopByte ;BX = first MCB xor si,si ;Zero previous ptr. p2_loop: cmp bx,dx ;Found it? je p2_gotit test [byte bx+2],2 ;Last block? jnz p2_done mov si,bx ;Save block add bx,[bx] ;Next block jmp p2_loop ;Loop back p2_gotit: mov di,bx ;DI = next block add di,[bx] test [byte bx+2],2 ;Next block allocated jnz p2_cont1 ;or nonexistent, can't mov cl,[di+2] ;merge with it test cl,1 jnz p2_done mov ax,[di] ;Merge blocks: sum sizes, add [bx],ax ;set flags of second one mov [bx+2],cl p2_cont1: and [byte bx+2],0FEh ;Reset allocated flag test si,si ;Prev. block allocated jz p2_done ;or nonexistent, can't mov cl,[si+2] ;merge with it test cl,1 jnz p2_done mov ax,[bx] ;Merge blocks: sum sizes, add [si],ax ;set flags of second one mov cl,[bx+2] mov [si+2],cl p2_done: popa ;Restore registers pop bp ;Delete stack frame ret 2 ;Return EndP freemem ;****************** getmfree() -- Return largest free memory block ;unsigned getmfree(void); ptr equ bp+4 Proc getmfree push bp ;Set up stack frame mov bp,sp push bx ;Save registers mov bx,offset TopByte ;BX = first MCB xor ax,ax ;Zero counter p3_loop: test [byte bx+2],1 ;Not free, skip jnz p3_skip cmp ax,[bx] ;Biggest so far? jae p3_skip mov ax,[bx] ;Save largest block p3_skip: test [byte bx+2],2 ;Last block? jnz p3_done add bx,[bx] ;Next block jmp p3_loop ;Loop back p3_done: sub ax,3 ;Adjust to true size pop bx ;Restore registers pop bp ;Delete stack frame ret ;Return EndP getmfree End ~~~C_FARMEM Ideal Public faralloc,farfree,getfarfree Model Tiny P386 CodeSeg ;****************** faralloc() -- Allocate far memory ;int faralloc(int nparas); nparas equ bp+4 Proc faralloc push bp ;Set up stack frame mov bp,sp push bx ;Save BX mov ah,48h ;Allocate memory mov bx,[nparas] ;BX = paras int 21h ;DOS call jnc $+4 ;No error, return pointer xor ax,ax ;Error, return 0 pop bx ;Restore BX pop bp ;Delete stack frame ret 2 ;Return EndP faralloc ;****************** farfree() -- Free far memory ;void farfree(int ptr); ptr equ bp+4 Proc farfree push bp ;Set up stack frame mov bp,sp push es ax ;Save registers mov ah,4Ah ;Free memory mov es,[ptr] ;ES = pointer int 21h ;DOS call pop ax es ;Restore registers pop bp ;Delete stack frame ret 2 ;Return EndP farfree ;****************** getfarfree() -- Return largest free far memory block ;unsigned getfarfree(void); ptr equ bp+4 Proc getfarfree push bp ;Set up stack frame mov bp,sp push bx ;Save registers mov ah,48h ;Allocate memory mov bx,-1 ;-1 is invalid int 21h ;DOS call (returns an error) xchg ax,bx ;AX = size of largest free block pop bx ;Restore registers pop bp ;Delete stack frame ret ;Return EndP getfarfree End ~~~C_ATOI Ideal Public atoi,atol Model Tiny CodeSeg P386 ;****************** atoi() -- Convert string to int ;int atoi(char *strp); strp equ bp+4 Proc atoi push bp ;Set up stack frame mov bp,sp push dx [word strp] ;Save DX, call atol call atol pop dx ;Restore DX pop bp ;Delete stack frame ret 2 ;Return EndP atoi ;****************** atol() -- Convert string to long ;long atol(char *strp); strp equ bp+4 Proc atol push bp ;Set up stack frame mov bp,sp push si di ebx ecx ;Save registers mov si,[strp] ;SI = string xor ecx,ecx ;ECX = 0 xor ebx,ebx ;EBX = 0 p1_ploop: mov bl,[si] ;Load char inc si cmp bl,' ' ;Loop while char is space je p1_ploop ;(20h, or 09h thru 0Dh) cmp bl,9 jna p1_cont cmp bl,13 jbe p1_ploop p1_cont: xor di,di ;DI = 0 cmp bl,'+' ;If char = '+', ignore je p1_loop cmp bl,'-' ;If char <> '-', keep it jne p1_skip inc di ;Set negative flag p1_loop: mov bl,[si] ;Load char inc si p1_skip: cmp bl,'9' ;Not a digit, finish ja p1_finish sub bl,'0' jc p1_finish imul ecx,10 ;Multiply by 10 add ecx,ebx ;Add in digit... jmp p1_loop ;Loop back p1_finish: xchg ax,cx ;DX:AX = result shr ecx,16 mov dx,cx dec di ;Positive, don't negate jl p1_done neg dx ;Negate the result neg ax sbb dx,0 p1_done: pop ecx ebx di si ;Restore registers pop bp ;Delete stack frame ret 2 ;Return EndP atol End ~~~C_ITOA Ideal Public itoa Model Tiny CodeSeg P386 ;****************** itoa() -- Convert int to string ;void itoa(int n, char *strp); n equ bp+6 strp equ bp+4 Proc itoa push bp ;Set up stack frame mov bp,sp pusha ;Save all registers mov ax,[n] ;AX = n mov di,[strp] ;DI = string pointer test ax,ax ;Negative? jge p1_noneg mov [byte di],'-' ;Store minus sign inc di neg ax ;Make it positive p1_noneg: xor cx,cx ;Zero CX test ax,ax ;Check for zero jnz p1_nozero push '0' ;Push a zero inc cx ;One digit jmp p1_ploop p1_nozero: mov si,10 ;SI = 10 p1_dloop: xor dx,dx ;Divide by 10 div si mov bl,dl ;Remainder in BL add bl,30h ;Convert to digit push bx ;Push digit inc cx test ax,ax ;Loop back jnz p1_dloop p1_ploop: pop ax ;Pop digit mov [di],al ;Store digit inc di loop p1_ploop ;Loop back mov [byte di],0 ;Add the null byte popa ;Restore registers pop bp ;Delete stack frame ret 4 ;Return EndP itoa End ~~~C_LTOA Ideal Extrn itoa:near Public ltoa Model Tiny CodeSeg P386 ;****************** ltoa() -- Convert long to string ;void ltoa(long n, char *strp); n equ bp+6 strp equ bp+4 Proc ltoa push bp ;Set up stack frame mov bp,sp pushad ;Save all registers mov eax,[n] ;EAX = n mov di,[strp] ;DI = string pointer test eax,eax ;Negative? jge p1_noneg mov [byte di],'-' ;Store minus sign inc di neg eax ;Make it positive p1_noneg: xor cx,cx ;Zero CX test eax,eax ;Check for zero jnz p1_nozero push '0' ;Push a zero inc cx ;One digit jmp p1_ploop p1_nozero: mov si,10 ;SI = 10 p1_dloop: xor edx,edx ;Divide by 10 div si mov bl,dl ;Remainder in BL add bl,30h ;Convert to digit push bx ;Push digit inc cx test eax,eax ;Loop back jnz p1_dloop p1_ploop: pop ax ;Pop digit mov [di],al ;Store digit inc di loop p1_ploop ;Loop back mov [byte di],0 ;Add the null byte popad ;Restore registers pop bp ;Delete stack frame ret 6 ;Return EndP ltoa End ~~~C_PUTS Ideal Extrn PUT_CHAR:near Public puts,xputs Model Tiny CodeSeg P386 ;****************** puts() -- Print string ;void puts(char *strp); strp equ bp+4 Proc puts push bp ;Set up stack frame mov bp,sp pusha ;Save all registers mov si,[strp] ;SI = string pointer p1_loop: lodsb ;Get char test al,al ;Check for null jz p1_done call PUT_CHAR ;Output char jmp p1_loop ;Loop back p1_done: popa ;Restore registers pop bp ;Delete stack frame ret 2 ;Return EndP puts ;****************** xputs() -- Print string, generalized ;void xputs(void *func, int strp); func equ bp+6 strp equ bp+4 Proc xputs push bp ;Set up stack frame mov bp,sp pusha ;Save all registers mov si,[strp] ;SI = string pointer mov bx,[func] ;BX = function p2_loop: lodsb ;Get char test al,al ;Check for null jz p2_done push ax ;Output char call bx jmp p2_loop ;Loop back p2_done: popa ;Restore registers pop bp ;Delete stack frame ret 4 ;Return EndP xputs End ~~~C_FPUTS Ideal Extrn fputc:near Public fputs Model Tiny CodeSeg P386 ;****************** fputs() -- Print string to file ;int fputs(int fp, char *strp); fp equ bp+6 strp equ bp+4 Proc fputs push bp ;Set up stack frame mov bp,sp push bx si ;Save registers mov si,[strp] ;SI = string pointer mov bx,[fp] ;BX = file pointer p1_loop: lodsb ;Get char test al,al ;Check for null jz p1_done push bx ax ;Output char: call fputc ;fputc(fp, AX); test ax,ax jnl p1_loop ;Loop back p1_done: pop si bx ;Restore registers pop bp ;Delete stack frame ret 4 ;Return EndP fputs End ~~~C_GETS Ideal Public gets,xgets Model Tiny CodeSeg P386 ;****************** gets() -- Get string ;void gets(char *strp, int max); strp equ bp+6 max equ bp+4 Proc gets push bp ;Set up stack frame mov bp,sp pusha ;Save all registers push es mov di,[strp] ;DI = string pointer mov cx,[max] ;CX = max string length dec cx p1_loop: xor ax,ax ;Get key int 16h test al,al ;Ignore extended keys jz p1_loop cmp al,8 ;Backspace? je p1_bksp int 29h ;Show char (on screen) cmp al,13 ;<Enter> = done je p1_done jcxz p1_loop ;Maxed out, don't store mov [di],al ;Store char inc di dec cx ;Decrement maximum jmp p1_loop ;Loop back p1_bksp: cmp di,[strp] ;At beginning, do nothing je p1_loop dec di ;Decrement string pointer inc cx ;Increment maximum push cx ;Save CX mov ah,0Fh ;Get video page int 10h mov ah,3 ;Get cursor position int 10h ;in DH/DL dec dx ;Move left one column test dl,dl ;if at zero moves up too jnl p1_nowrap push 0 ;DL = last column pop es mov dl,[es:044Ah] dec dx p1_nowrap: mov ah,2 ;Set cursor position int 10h mov ax,0A20h ;Clear char at current mov cx,1 ;cursor position int 10h pop cx ;Restore CX jmp p1_loop ;Loop back p1_done: mov al,10 ;Output LF int 29h mov [byte di],0 ;Terminate string pop es ;Restore registers popa pop bp ;Delete stack frame ret 4 ;Return EndP gets ;****************** xgets() -- Get string, generalized ;void xgets(void *func, char *strp, int max, int term); strp equ bp+10 func equ bp+8 max equ bp+6 term equ bp+4 Proc xgets push bp ;Set up stack frame mov bp,sp pusha ;Save all registers mov di,[strp] ;DI = string pointer mov bx,[func] ;BX = function mov cx,[max] ;CX = max string length dec cx mov dx,[term] ;DX = terminator p2_loop: call bx ;Get char cmp al,dl ;Check for terminator je p2_done jcxz p1_loop ;Maxed out, don't store mov [di],al ;Store char inc di dec cx ;Decrement maximum jmp p2_loop ;Loop back p2_done: mov [byte di],0 ;Terminate string popa ;Restore registers pop bp ;Delete stack frame ret 8 ;Return EndP xgets End ~~~C_FGETS Ideal Extrn fgetc:near Public fgets Model Tiny CodeSeg P386 ;****************** fgets() -- Get string from file ;void fgets(int fp, char *strp, int max); fp equ bp+8 strp equ bp+6 max equ bp+4 Proc fgets push bp ;Set up stack frame mov bp,sp push bx cx dx di ;Save all registers mov di,[strp] ;DI = string pointer mov bx,[fp] ;BX = file pointer mov cx,[max] ;CX = max string length dec cx p1_loop: push bx ;Get char call fgetc test ax,ax ;Check for EOF jl p1_quit cmp al,13 ;CR = done je p1_done jcxz p1_loop ;Maxed out, don't store mov [di],al ;Store char inc di dec cx ;Decrement maximum jmp p1_loop ;Loop back p1_done: push bx ;Remove LF call fgetc xor ax,ax p1_quit: mov [byte di],0 ;Terminate string pop di dx cx bx ;Restore registers pop bp ;Delete stack frame ret 6 ;Return EndP fgets End ~~~C_PRTBUF Ideal Public PRT_BUF Model Tiny CodeSeg P386 ;****************** PRT_BUF -- String buffer for printf(), etc. PRT_BUF db 20 dup(0) End ~~~C_PRINTF Ideal Extrn PRT_BUF:byte,itoa:near,ltoa:near Extrn PUT_CHAR:near Public printf Model Tiny CodeSeg P386 ;****************** printf() -- Print formatted string ;void printf(char *fmt, void *args); fmt equ bp+6 args equ bp+4 Proc printf push bp ;Set up stack frame mov bp,sp pusha ;Save all registers mov si,[fmt] ;SI = string pointer mov bx,[args] ;BX = arg pointer p1_loop: lodsb ;Get char test al,al ;Check for null jz p1_done cmp al,'%' ;Check for '%' je p1_proc p1_putc: call PUT_CHAR ;Output char jmp p1_loop ;Loop back p1_proc: lodsb ;Get char test al,al ;Check for null jz p1_done cmp al,'%' ; %% = percent je p1_putc cmp al,'d' ; %d = integer je p1_int cmp al,'l' ; %l = long int je p1_long cmp al,'x' ; %x = hex je p1_hex cmp al,'c' ; %c = char je p1_char cmp al,'s' ; %s = string je p1_str jmp p1_loop ;Invalid, ignore p1_done: popa ;Restore registers pop bp ;Delete stack frame ret 4 ;Return p1_long: lodsb ;Get char test al,al ;Check for null jz p1_done cmp al,'d' ; %ld = long integer je p1_lint cmp al,'x' ; %lx = long hex je p1_lhex jmp p1_loop ;Invalid, ignore p1_int: push [word bx] ;itoa(*bx, PRT_BUF); push offset PRT_BUF call itoa inc bx ;Advance pointer inc bx mov di,offset PRT_BUF ;Print alpha string jmp p1_alpha p1_lint: push [dword bx] ;ltoa(*bx, PRT_BUF); push offset PRT_BUF call ltoa add bx,4 ;Advance pointer mov di,offset PRT_BUF ;Print alpha string jmp p1_alpha p1_hex: mov ax,[bx] ;AX = arg call p1_chex ;Convert to hex inc bx ;Advance pointer inc bx jmp p1_loop ;Loop back p1_lhex: mov ax,[bx+2] ;AX = high word call p1_chex ;Convert to hex mov ax,[bx] ;AX = low word call p1_chex ;Convert to hex add bx,4 ;Advance pointer jmp p1_loop ;Loop back p1_char: mov al,[bx] ;Output char int 29h inc bx ;Advance pointer jmp p1_loop ;Loop back p1_str: mov al,[bx] ;Get char inc bx ;Advance pointer test al,al ;Check for null jz p1_sdone call PUT_CHAR ;Output char jmp p1_str ;Loop back p1_sdone: jmp p1_loop ;Return to main loop p1_alpha: mov al,[di] ;Get char test al,al ;Check for null jz p1_sdone call PUT_CHAR ;Output char inc di ;Advance pointer jmp p1_alpha ;Loop back p1_chex: mov cx,4 ;4 hex digits xchg al,ah ;Reverse the order ror ah,cl ;of the hex digits ror al,cl ;in AX p1_hloop: push ax ;Save AX and al,0Fh ;Keep 4 bits cmp al,0Ah ;Compute the hex digit, sbb al,69h ;using Improved Allison's Algorithm das call PUT_CHAR ;Output char pop ax ;Restore AX shr ax,4 ;Shift it over loop p1_hloop ;Loop back ret ;Return EndP printf End ~~~C_SPRINT Ideal Extrn PRT_BUF:byte,itoa:near,ltoa:near Public sprintf Model Tiny CodeSeg P386 ;****************** sprintf() -- Print formatted string into string ;void sprintf(char *strp, char *fmt, void *args); strp equ bp+8 fmt equ bp+6 args equ bp+4 Proc sprintf push bp ;Set up stack frame mov bp,sp pusha ;Save all registers mov di,[strp] ;DI = string pointer mov si,[fmt] ;SI = format pointer mov bx,[args] ;BX = arg pointer p1_loop: lodsb ;Get char test al,al ;Check for null jz p1_done cmp al,'%' ;Check for '%' je p1_proc p1_putc: stosb ;Output char jmp p1_loop ;Loop back p1_proc: lodsb ;Get char test al,al ;Check for null jz p1_done cmp al,'%' ; %% = percent je p1_putc cmp al,'d' ; %d = integer je p1_int cmp al,'l' ; %l = long int je p1_long cmp al,'x' ; %x = hex je p1_hex cmp al,'c' ; %c = char je p1_char cmp al,'s' ; %s = string je p1_str jmp p1_loop ;Invalid, ignore p1_done: xor al,al ;Store a null byte stosb popa ;Restore registers pop bp ;Delete stack frame ret 6 ;Return p1_long: lodsb ;Get char test al,al ;Check for null jz p1_done cmp al,'d' ; %ld = long integer je p1_lint cmp al,'x' ; %lx = long hex je p1_lhex jmp p1_loop ;Invalid, ignore p1_int: push [word bx] ;itoa(*bx, PRT_BUF); push offset PRT_BUF call itoa inc bx ;Advance pointer inc bx mov bp,offset PRT_BUF ;Print alpha string jmp p1_alpha p1_lint: push [dword bx] ;ltoa(*bx, PRT_BUF); push offset PRT_BUF call ltoa add bx,4 ;Advance pointer mov bp,offset PRT_BUF ;Print alpha string jmp p1_alpha p1_hex: mov ax,[bx] ;AX = arg call p1_chex ;Convert to hex inc bx ;Advance pointer inc bx jmp p1_loop ;Loop back p1_lhex: mov ax,[bx+2] ;AX = high word call p1_chex ;Convert to hex mov ax,[bx] ;AX = low word call p1_chex ;Convert to hex add bx,4 ;Advance pointer jmp p1_loop ;Loop back p1_char: mov al,[bx] ;Output char stosb inc bx ;Advance pointer jmp p1_loop ;Loop back p1_str: mov al,[bx] ;Get char inc bx ;Advance pointer test al,al ;Check for null jz p1_sdone stosb ;Output char jmp p1_str ;Loop back p1_sdone: jmp p1_loop ;Return to main loop p1_alpha: mov al,[bp] ;Get char test al,al ;Check for null jz p1_sdone stosb ;Output char inc bp ;Advance pointer jmp p1_alpha ;Loop back p1_chex: mov cx,4 ;4 hex digits xchg al,ah ;Reverse the order ror ah,cl ;of the hex digits ror al,cl ;in AX p1_hloop: push ax ;Save AX and al,0Fh ;Keep 4 bits cmp al,0Ah ;Compute the hex digit, sbb al,69h ;using Improved Allison's Algorithm das stosb ;Output char pop ax ;Restore AX shr ax,4 ;Shift it over loop p1_hloop ;Loop back ret ;Return EndP sprintf End ~~~C_FPRINT Ideal Extrn PRT_BUF:byte,fputc:near,itoa:near,ltoa:near Public fprintf Model Tiny CodeSeg P386 ;****************** fprintf() -- Print formatted string to file ;void fprintf(int fp, char *fmt, void *args); fp equ bp+8 fmt equ bp+6 args equ bp+4 Proc fprintf push bp ;Set up stack frame mov bp,sp pusha ;Save all registers mov dx,[fp] ;DX = file pointer mov si,[fmt] ;SI = string pointer mov bx,[args] ;BX = arg pointer p1_loop: lodsb ;Get char test al,al ;Check for null jz p1_done cmp al,'%' ;Check for '%' je p1_proc p1_putc: push dx ax ;Output char call fputc jmp p1_loop ;Loop back p1_proc: lodsb ;Get char test al,al ;Check for null jz p1_done cmp al,'%' ; %% = percent je p1_putc cmp al,'d' ; %d = integer je p1_int cmp al,'l' ; %l = long int je p1_long cmp al,'x' ; %x = hex je p1_hex cmp al,'c' ; %c = char je p1_char cmp al,'s' ; %s = string je p1_str jmp p1_loop ;Invalid, ignore p1_done: popa ;Restore registers pop bp ;Delete stack frame ret 6 ;Return p1_long: lodsb ;Get char test al,al ;Check for null jz p1_done cmp al,'d' ; %ld = long integer je p1_lint cmp al,'x' ; %lx = long hex je p1_lhex jmp p1_loop ;Invalid, ignore p1_int: push [word bx] ;itoa(*bx, PRT_BUF); push offset PRT_BUF call itoa inc bx ;Advance pointer inc bx mov di,offset PRT_BUF ;Print alpha string jmp p1_alpha p1_lint: push [dword bx] ;ltoa(*bx, PRT_BUF); push offset PRT_BUF call ltoa add bx,4 ;Advance pointer mov di,offset PRT_BUF ;Print alpha string jmp p1_alpha p1_hex: mov ax,[bx] ;AX = arg call p1_chex ;Convert to hex inc bx ;Advance pointer inc bx jmp p1_loop ;Loop back p1_lhex: mov ax,[bx+2] ;AX = high word call p1_chex ;Convert to hex mov ax,[bx] ;AX = low word call p1_chex ;Convert to hex add bx,4 ;Advance pointer jmp p1_loop ;Loop back p1_char: mov al,[bx] ;Output char push dx ax call fputc inc bx ;Advance pointer jmp p1_loop ;Loop back p1_str: mov al,[bx] ;Get char inc bx ;Advance pointer test al,al ;Check for null jz p1_sdone push dx ax ;Output char call fputc jmp p1_str ;Loop back p1_sdone: jmp p1_loop ;Return to main loop p1_alpha: mov al,[di] ;Get char test al,al ;Check for null jz p1_sdone push dx ax ;Output char call fputc inc di ;Advance pointer jmp p1_alpha ;Loop back p1_chex: mov cx,4 ;4 hex digits xchg al,ah ;Reverse the order ror ah,cl ;of the hex digits ror al,cl ;in AX p1_hloop: push ax ;Save AX and al,0Fh ;Keep 4 bits cmp al,0Ah ;Compute the hex digit, sbb al,69h ;using Improved Allison's Algorithm das push dx ax ;Output char call fputc pop ax ;Restore AX shr ax,4 ;Shift it over loop p1_hloop ;Loop back ret ;Return EndP fprintf End ~~~C_XPRINT Ideal Extrn PRT_BUF:byte,itoa:near,ltoa:near Public xprintf Model Tiny CodeSeg P386 ;****************** xprintf() -- Print formatted string, generalized ;void xprintf(void *func, char *fmt, void *args); func equ bp+8 fmt equ bp+6 args equ bp+4 Proc xprintf push bp ;Set up stack frame mov bp,sp pusha ;Save all registers mov dx,[func] ;DX = function pointer mov si,[fmt] ;SI = string pointer mov bx,[args] ;BX = arg pointer p1_loop: lodsb ;Get char test al,al ;Check for null jz p1_done cmp al,'%' ;Check for '%' je p1_proc p1_putc: push ax ;Output char call dx jmp p1_loop ;Loop back p1_proc: lodsb ;Get char test al,al ;Check for null jz p1_done cmp al,'%' ; %% = percent je p1_putc cmp al,'d' ; %d = integer je p1_int cmp al,'l' ; %l = long int je p1_long cmp al,'x' ; %x = hex je p1_hex cmp al,'c' ; %c = char je p1_char cmp al,'s' ; %s = string je p1_str jmp p1_loop ;Invalid, ignore p1_done: popa ;Restore registers pop bp ;Delete stack frame ret 6 ;Return p1_long: lodsb ;Get char test al,al ;Check for null jz p1_done cmp al,'d' ; %ld = long integer je p1_lint cmp al,'x' ; %lx = long hex je p1_lhex jmp p1_loop ;Invalid, ignore p1_int: push [word bx] ;itoa(*bx, PRT_BUF); push offset PRT_BUF call itoa inc bx ;Advance pointer inc bx mov di,offset PRT_BUF ;Print alpha string jmp p1_alpha p1_lint: push [dword bx] ;ltoa(*bx, PRT_BUF); push offset PRT_BUF call ltoa add bx,4 ;Advance pointer mov di,offset PRT_BUF ;Print alpha string jmp p1_alpha p1_hex: mov ax,[bx] ;AX = arg call p1_chex ;Convert to hex inc bx ;Advance pointer inc bx jmp p1_loop ;Loop back p1_lhex: mov ax,[bx+2] ;AX = high word call p1_chex ;Convert to hex mov ax,[bx] ;AX = low word call p1_chex ;Convert to hex add bx,4 ;Advance pointer jmp p1_loop ;Loop back p1_char: mov al,[bx] ;Output char push ax call dx inc bx ;Advance pointer jmp p1_loop ;Loop back p1_str: mov al,[bx] ;Get char inc bx ;Advance pointer test al,al ;Check for null jz p1_sdone push ax ;Output char call dx jmp p1_str ;Loop back p1_sdone: jmp p1_loop ;Return to main loop p1_alpha: mov al,[di] ;Get char test al,al ;Check for null jz p1_sdone push ax ;Output char call dx inc di ;Advance pointer jmp p1_alpha ;Loop back p1_chex: mov cx,4 ;4 hex digits xchg al,ah ;Reverse the order ror ah,cl ;of the hex digits ror al,cl ;in AX p1_hloop: push ax ;Save AX and al,0Fh ;Keep 4 bits cmp al,0Ah ;Compute the hex digit, sbb al,69h ;using Improved Allison's Algorithm das push ax ;Output char call dx pop ax ;Restore AX shr ax,4 ;Shift it over loop p1_hloop ;Loop back ret ;Return EndP xprintf End ~~~C_CPULVL Ideal Public cputype Model Tiny P186 CodeSeg ;**************************** cputype() -- Returns CPU level ;int cputype(void); Proc cputype pusha ;Save all registers call p1_getcpu ;Call main procedure shr ax,8 ;AL = AH, AH = 0 mov bp,sp ;Change pushed AX mov [bp+14],ax popa ;Restore registers ret ;Return p1_getcpu: mov cx,0121h ;If CH can be shifted by 21h, shl ch,cl ;then it's an 8086, because jz p1_8086 ;a 186+ limits shift counts. push sp ;If SP is pushed as its pop ax ;original value, then cmp ax,sp ;it's a 286+. jne p1_186 pushf ;Save flags cli ;No interrupts pushf ;AX = flags pop ax xor ax,7000h ;Toggle IOPL bit push ax ;Flags = AX popf pushf ;BX = flags pop bx popf ;Restore flags cmp ax,bx ;If the bit was not jne p1_286 ;reset, it's a 386+ P386 push bp ;Align stack to dword mov bp,sp and sp,0FFFCh pushfd ;Save eflags cli ;No interrupts pushfd ;EAX = eflags pop eax mov ebx,eax ;EBX = eflags xor eax,40000h ;Toggle AC bit push eax ;Eflags = EAX popfd pushfd ;EAX = eflags pop eax popfd ;Restore eflags mov sp,bp ;Restore stack pop bp cmp eax,ebx ;If the bit was not je p1_386 ;reset, it's a 486+ pushfd ;Save eflags cli ;No interrupts pushfd ;EAX = eflags pop eax xor eax,200000h ;Toggle ID bit push eax ;Eflags = EAX popfd pushfd ;EBX = eflags pop ebx popfd ;Restore eflags cmp eax,ebx ;If the bit was not jne p1_486 ;reset, it's a 586+ P586 xor eax,eax ;EAX = 1 inc ax cpuid ;Get CPU type ret ;Return P186 p1_486: mov ah,4 ;486, return 4 ret p1_386: mov ah,3 ;386, return 3 ret p1_286: mov ah,2 ;286, return 2 ret p1_186: mov ah,1 ;186, return 1 ret p1_8086: mov ah,0 ;8086, return 0 ret EndP cputype End ~~~C_FPULVL Ideal Public fputype Model Tiny P186 CodeSeg ;**************************** fputype() -- Returns FPU level, init FPU ;int fputype(void); -1 means no FPU Proc fputype pusha ;Save all registers call p2_getfpu ;Get FPU type mov bp,sp ;Change pushed AX mov [bp+14],ax popa ;Restore registers ret ;Return P8087 p2_getfpu: fninit ;Initialize FPU mov [Junk],55AAh ;Set junk value fnstsw [Junk] ;Store status word cmp [byte Junk],0 ;If it's not 0, no FPU jne p2_nofpu fnstcw [Junk] ;Store control word mov ax,[Junk] ;If the bits are not the way and ax,103Fh ;they should be, no FPU cmp ax,3Fh jne p2_nofpu and [Junk],0FF7Fh ;Clear interrupt bit fldcw [Junk] ;Load control word fdisi ;Disable interrupts fstcw [Junk] ;Store control word test [Junk],80h ;If it changed, it's an 8087 jnz p2_8087 P286 P287 finit ;Re-initialize fld1 ;Divide 1 by 0 to get fldz ;a positive infinity fdiv fld st ;Get a negative infinity fchs fcompp ;Compare them fstsw ax ;Store status word sahf ;If the FPU thought that they je p2_287 ;were equal, it's a 287 mov ax,3 ;387, return 3 finit ;Init processor ret p2_287: mov ax,2 ;287, return 2 finit ;Init processor ret P186 P8087 p2_8087: xor ax,ax ;8087, return 0 finit ;Init processor ret p2_nofpu: mov ax,-1 ;No FPU, return -1 ret Junk dw 0 EndP fputype End ~~~C_RAND Ideal Public rand,srand,truerand Model Tiny P386 CodeSeg RandNum dd 0 ;Random number ;****************** rand() -- Returns a random number below N ;int rand(int max); max equ bp+4 Proc rand push bp ;Set up stack frame mov bp,sp push bx edx ;Save registers imul edx,[RandNum],19660Dh add edx,10DCDh ;EAX = RandNum * 19660Dh + 10DCDh mov [RandNum],edx ;Save random number shr edx,15 ;AX = bits 15-30 xchg ax,dx mov bx,[max] ;BX = maximum xor dx,dx ;Zero DX test bx,bx ;Can't divide by zero jz p1_skip div bx ;Divide by BX p1_skip: xchg ax,dx ;Result in AX pop edx bx ;Restore registers pop bp ;Delete stack frame ret 2 ;Return EndP rand ;****************** srand() -- Seeds the RNG with the time ;void srand(void); Proc srand push bp ;Set up stack frame mov bp,sp push es eax ;Save registers push 40h ;ES = BIOS segment pop es mov eax,[es:6Ch] ;Get low word mov [RandNum],eax ;Save it pop eax es ;Restore registers pop bp ;Delete stack frame ret ;Return EndP srand ;****************** truerand() -- Returns a true random number below N ;int truerand(int max); Extremely slow, but it works max equ bp+4 Proc truerand push bp ;Set up stack frame mov bp,sp push bx cx dx ;Save registers mov cx,96 ;96 iterations cli ;No interrupts allowed p1_loop: mov al,06h ;Set timer command out 43h,al jmp $+2 in al,40h ;Read LSB of timer xor dl,al ;XOR into DX jmp $+2 in al,40h ;Read MSB of timer xor dl,al ;XOR into DX rol dx,3 ;Rotate left loop p1_loop ;Loop back sti ;Enable interrupts xchg ax,dx ;Result in AX mov bx,[max] ;BX = maximum xor dx,dx ;Zero DX test bx,bx ;Can't divide by zero jz p3_skip div bx ;Divide by BX p3_skip: xchg ax,dx ;Result in AX pop dx cx bx ;Restore registers pop bp ;Delete stack frame ret 2 ;Return EndP truerand End ~~~C_DELAY Ideal Public delay Model Tiny P386 CodeSeg ;****************** delay() -- Delay in milliseconds ;void delay(int dtime); dtime equ bp+4 Proc delay push bp ;Set up stack frame mov bp,sp pusha ;Save registers mov ax,[dtime] ;AX = time in milliseconds mov dx,1000 ;Multiply by 1000 mul dx ;DX:AX = time in microseconds mov cx,dx ;CX:DX = time xchg dx,ax mov ah,86h ;BIOS Delay Service int 15h popa ;Restore registers pop bp ;Delete stack frame ret 2 ;Return EndP delay End ~~~C_SOUND Ideal Public sound,nosound Model Tiny P386 CodeSeg ;****************** sound() -- Turn on speaker at specific frequency ;void sound(int freq); freq equ bp+4 Proc sound push bp ;Set up stack frame mov bp,sp pusha ;Save registers mov dx,12h ;BX = 1193180 / freq. mov ax,34DCh mov bx,[freq] div bx xchg bx,ax mov al,0B6h ;Set frequency out 43h,al mov al,bl out 42h,al mov al,bh out 42h,al in al,61h ;Turn on speaker or al,3 out 61h,al popa ;Restore registers pop bp ;Delete stack frame ret 2 ;Return EndP sound ;****************** nosound() -- Turn off speaker ;void nosound(void); Proc nosound push ax ;Save AX in al,61h ;Turn off speaker and al,0FCh out 61h,al pop ax ;Restore AX ret ;Return EndP nosound End