;* MUTILS.ASM
;*
;* Miscellaneous utility functions for MIDAS Sound System used
;* by various system components.
;*
;* $Id: mutils.asm,v 1.4 1997/01/16 18:41:59 pekangas Exp $
;*
;* Copyright 1996,1997 Housemarque Inc.
;*
;* This file is part of the MIDAS Sound System, and may only be
;* used, modified and distributed under the terms of the MIDAS
;* Sound System license, LICENSE.TXT. By continuing to use,
;* modify or distribute this file you indicate that you have
;* read the license and understand and accept it fully.
;*
; Possibly environment dependent code is marked with *!!*
IDEAL
P386
INCLUDE "lang.inc"
INCLUDE "mutils.inc"
DATASEG
IFDEF __WC32__
EXTRN _psp : word
ENDIF
CODESEG
;/***************************************************************************\
;*
;* Function: int mGetKey(void)
;*
;* Description: Waits for a keypress and returns the read key
;*
;* Returns: ASCII code for the key pressed. Extended keycodes are
;* returned with bit 8 set, eg. up arrow becomes \x148.
;*
;\***************************************************************************/
PROC mGetKey _funct
USES _bx
;*!!*
IFDEF __32__
xor eax,eax
ENDIF
mov ax,0700h ; read key without echo
int 21h
xor ah,ah
test al,al ; read key zero?
jnz @@keyok ; if not, it is the key ASCII code
; the read key was zero - now read the actual extended keycode and
; return it with bit 8 set.
mov ax,0700h ; read key without echo
int 21h
mov ah,1 ; set bit 8 to 1
@@keyok:
ret
ENDP
;/***************************************************************************\
;*
;* Function: int mStrLength(char *str)
;*
;* Description: Calculates the length of a ASCIIZ string
;*
;* Input: char *str pointer to string
;*
;* Returns: String length excluding the terminating '\0'.
;*
;\***************************************************************************/
PROC mStrLength _funct str : _ptr
USES _bx
IFDEF __32__
mov ax,ds
mov es,ax
ENDIF
LOADPTR es,_bx,[str] ; point es:bx to string
xor _ax,_ax ; current length = 0
@@lp:
cmp [byte _esbx],0 ; is current byte 0
je @@done ; if is, we are finished
inc _bx ; next byte
inc _ax
jmp @@lp
@@done:
ret
ENDP
;/***************************************************************************\
;*
;* Function: void mStrCopy(char *dest, char *src);
;*
;* Description: Copies an ASCIIZ string from *src to *dest.
;*
;* Input: char *dest pointer to destination string
;* char *src pointer to source string
;*
;\***************************************************************************/
PROC mStrCopy _funct dest : _ptr, src : _ptr
USES _si,_di
PUSHSEGREG ds
; Clear enough as it is? If not, maybe you shouldn't be reading
; this source after all...
IFDEF __32__
mov ax,ds
mov es,ax
ENDIF
cld
LOADPTR ds,_si,[src]
LOADPTR es,_di,[dest]
@@lp: lodsb
stosb
test al,al
jnz @@lp
@@done:
POPSEGREG ds
ret
ENDP
;/***************************************************************************\
;*
;* Function: void mStrAppend(char *dest, char *src);
;*
;* Description: Appends an ASCIIZ string to the end of another.
;*
;* Input: char *dest pointer to destination string
;* char *src pointer to source string
;*
;\***************************************************************************/
PROC mStrAppend _funct dest : _ptr, src : _ptr
USES _si,_di
; Again, if you don't understand this you should perhaps consider
; switching hobby...
PUSHSEGREG ds
IFDEF __32__
mov ax,ds
mov es,ax
ENDIF
cld
LOADPTR ds,_si,[src]
LOADPTR es,_di,[dest]
@@l1: mov al,[_esdi]
test al,al
jz @@lp
inc _di
jmp @@l1
@@lp: lodsb
stosb
test al,al
jz @@done
jmp @@lp
@@done:
POPSEGREG ds
ret
ENDP
;/***************************************************************************\
;*
;* Function: void mMemCopy(char *dest, char *src, unsigned numBytes);
;*
;* Description: Copies a memory block from *src to *dest.
;*
;* Input: char *dest pointer to destination
;* char *src pointer to source
;* unsigned numBytes number of bytes to copy
;*
;\***************************************************************************/
PROC mMemCopy _funct dest : _ptr, src : _ptr, numBytes : _int
USES _si,_di
IFDEF __32__
mov ax,ds
mov es,ax
ENDIF
PUSHSEGREG ds
cld
LOADPTR ds,_si,[src]
LOADPTR es,_di,[dest]
mov _cx,[numBytes]
rep movsb
POPSEGREG ds
ret
ENDP
;/***************************************************************************\
;*
;* Function: int mMemEqual(char *m1, char *m2, unsigned numBytes);
;*
;* Description: Compares two memory blocks.
;*
;* Input: char *m1 pointer to memory block #1
;* char *m2 pointer to memory block #2
;* unsigned numBytes number of bytes to compare
;*
;* Returns: 1 if the memory blocks are equal, 0 if not.
;*
;\***************************************************************************/
PROC mMemEqual _funct m1 : _ptr, m2 : _ptr, numBytes : _int
USES _si,_di
IFDEF __32__
mov ax,ds
mov es,ax
ENDIF
PUSHSEGREG ds
cld
LOADPTR ds,_si,[m1]
LOADPTR es,_di,[m2]
mov _cx,[numBytes]
repe cmpsb
test _cx,_cx
jnz @@une
mov _ax,1
jmp @@done
@@une: xor _ax,_ax
@@done:
POPSEGREG ds
ret
ENDP
;/***************************************************************************\
;*
;* Function: long mHex2Long(char *hex)
;*
;* Description: Converts a hexadecimal string to a long integer.
;*
;* Input: char *hex pointer to hex string, ASCIIZ
;*
;* Returns: Value of the string or -1 if conversion failure.
;*
;\***************************************************************************/
PROC mHex2Long _funct hex : _ptr
USES _bx
LOADPTR es,_bx,[hex] ; point es:bx to string
xor edx,edx ; current number is zero
@@lp: mov al,[_esbx] ; get character from string
inc _bx
test al,al ; terminating '\0'?
jz @@strend
shl edx,4 ; move previous string data to left
cmp al,'0' ; character below '0'?
jb @@err ; if yes, error
cmp al,'9' ; character <= '9'?
jbe @@decdigit ; if yes, it's a decimal digit
cmp al,'A' ; character below 'A'?
jb @@err ; if yes, error
cmp al,'F' ; character <= 'F'?
jbe @@chexdigit ; if yes, it's a capital hex digit
cmp al,'a' ; character below 'a'?
jb @@err ; if yes, error
cmp al,'f' ; character <= 'f'?
jbe @@shexdigit ; if yes, it's a small hex digit
jmp @@err ; unrecognized character - error
@@decdigit:
sub al,'0' ; al = current digit value
or dl,al ; add it to edx
jmp @@lp ; and get next character
@@chexdigit:
sub al,'A'-0Ah ; al = current digit value
or dl,al ; add it to edx
jmp @@lp ; and get next character
@@shexdigit:
sub al,'a'-0Ah ; al = current digit value
or dl,al ; add it to edx
jmp @@lp ; and get next character
@@strend:
IFDEF __16__
mov ax,dx ; move result from edx to dx:ax
shr edx,16
ELSE
mov eax,edx
ENDIF
jmp @@done ; and leave
@@err:
IFDEF __16__
mov ax,-1
mov dx,-1
ELSE
mov _ax,-1
ENDIF
@@done:
ret
ENDP
;/***************************************************************************\
;*
;* Function: long mDec2Long(char *dec)
;*
;* Description: Converts an unsigned decimal string to a long integer
;*
;* Input: char *dec pointer to string, ASCIIZ
;*
;* Returns: Value of the string or -1 if conversion failure.
;*
;\***************************************************************************/
PROC mDec2Long _funct dec : _ptr
USES _bx
LOADPTR es,_bx,[dec] ; point es:bx to string
xor edx,edx ; current value is zero
xor eax,eax
@@lp:
mov al,[_esbx] ; get character from string
inc bx
test al,al ; terminating '\0'?
jz @@strend
imul edx,edx,10 ; multiply current value by 10 to
; make room for the new digit
cmp al,'0' ; character below '0'?
jb @@err ; if yes, error
cmp al,'9' ; character above '9'?
ja @@err ; if yes, error
sub al,'0' ; al = current digit value
add edx,eax ; add it to edx
jmp @@lp ; and get next character
@@strend:
IFDEF __16__
mov ax,dx ; move result from edx to dx:ax
shr edx,16
ELSE
mov eax,edx
ENDIF
jmp @@done ; and leave
@@err:
IFDEF __16__
mov ax,-1
mov dx,-1
ELSE
mov eax,-1
ENDIF
@@done:
ret
ENDP
;/**************************************************************************\
;*
;* Function: char *mGetEnv(char *envVar);
;*
;* Description: Searches a string from the environment
;*
;* Input: envVar environment variable name, ASCIIZ
;*
;* Returns: Pointer to environment string value (ASCIIZ), NULL if string
;* was not found.
;*
;\**************************************************************************/
PROC mGetEnv _funct envVar : _ptr
USES _si,_di,_bx
;*!!*
PUSHSEGREG ds
IFDEF __32__
push es
mov ax,ds
mov es,ax
ENDIF
cld
LOADPTR es,_di,[envVar] ; point es:di and es:bx to environment
mov _bx,_di ; variable name
xor al,al
mov cx,7FFFh
repne scasb ; scan for first 0 in string
sub _di,_bx
dec _di
mov _dx,_di ; dx = string length (excl. '\0')
test _dx,_dx ; skip if zero length string
jz @@notfound
IFDEF __WC32__
mov bx,[_psp]
ELSE
mov ah,62h ; int 21h, function 62h - get PSP seg
int 21h ; bx = PSP segment
ENDIF
LOADPTR ds,_si,[envVar] ; point ds:si to variable name
mov es,bx ; es = PSP segment
mov es,[es:2Ch] ; es = Environment segment
xor _di,_di ; point es:di to environment
mov ah,[_si] ; ah = first character of string
xor al,al ; al = 0 !!!
@@search:
cmp [es:_di],ah ; Is the first letter of the current
jne @@skipend ; environment string same as the one
; we are looking for? If not, skip
; the whole string.
push _si
mov _cx,_dx
repe cmpsb ; check if the whole string is equal
pop _si
jne @@skipend ; skip if not
cmp [byte es:_di],"=" ; check is the next character is '='
jne @@skipend ; skip if not
inc _di ; point es:di to start of environment
IFDEF __16__
mov dx,es ; return pointer in dx:ax
mov ax,di
ELSE
mov eax,0006h ; DPMI function 7 - get segment base
xor ebx,ebx
mov bx,es
int 31h
jc @@notfound
mov eax,ecx ; eax = environment selector base
shl eax,16 ; address
mov ax,dx
add eax,edi
ENDIF
jmp @@done
@@skipend:
mov _cx,7FFFh
repne scasb ; search for first '\0'.
cmp [byte es:_di],0 ; is the next byte also 0?
je @@notfound ; if is, end of environment
jmp @@search
@@notfound:
xor _ax,_ax ; string was not found - return NULL
IFDEF __16__
xor dx,dx
ENDIF
@@done:
IFDEF __32__
pop es
ENDIF
POPSEGREG ds
ret
ENDP
;* $Log: mutils.asm,v $
;* Revision 1.4 1997/01/16 18:41:59 pekangas
;* Changed copyright messages to Housemarque
;*
;* Revision 1.3 1996/08/04 11:31:14 pekangas
;* All routines now preserve _ebx
;*
;* Revision 1.2 1996/07/13 17:28:46 pekangas
;* All routines now preserve ebx
;*
;* Revision 1.1 1996/05/22 20:49:33 pekangas
;* Initial revision
;*
END
