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source: xtideuniversalbios/trunk/Assembly_Library/Src/Display/DisplayFormat.asm@ 173

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Last change on this file since 173 was 134, checked in by Tomi Tilli, 14 years ago

Changes to Assembly Library:

Excluded some format specifiers and related printing functions not used by XTIDE Universal BIOS.

File size: 10.9 KB

Rev	Line
[41]	1	; Project name : Assembly Library
	2	; Description : Functions for displaying formatted strings.
	3
	4	; Section containing code
	5	SECTION .text
	6
	7	;--------------------------------------------------------------------
	8	; DisplayFormat_ParseCharacters
	9	; Parameters:
	10	; DS: BDA segment (zero)
[44]	11	; SS:BP: Pointer to first format parameter (-=2 updates to next parameter)
[41]	12	; CS:SI: Pointer to string to format
	13	; ES:DI: Ptr to cursor location in video RAM
	14	; Returns:
[44]	15	; CS:SI: Ptr to end of format string (ptr to one past NULL)
[41]	16	; DI: Updated offset to video RAM
	17	; Corrupts registers:
[44]	18	; AX, BX, CX, DX, BP
[41]	19	;--------------------------------------------------------------------
	20	ALIGN JUMP_ALIGN
	21	DisplayFormat_ParseCharacters:
[44]	22	call ReadCharacterAndTestForNull
[101]	23	jz SHORT ReturnFromFormat
[44]	24
	25	ePUSH_T cx, DisplayFormat_ParseCharacters ; Return address
	26	xor cx, cx ; Initial placeholder size
	27	cmp al, '%' ; Format specifier?
[101]	28	jne SHORT DisplayPrint_CharacterFromAL
	29	; Fall to ParseFormatSpecifier
[44]	30
[41]	31	;--------------------------------------------------------------------
[44]	32	; ParseFormatSpecifier
[41]	33	; Parameters:
[44]	34	; CX: Placeholder size
	35	; DS: BDA segment (zero)
	36	; SS:BP: Pointer to first format parameter (-=2 for next parameter)
	37	; CS:SI: Pointer to string to format
	38	; ES:DI: Ptr to cursor location in video RAM
	39	; Returns:
	40	; SI: Updated to first unparsed character
	41	; DI: Updated offset to video RAM
	42	; BP: Updated to next format parameter
	43	; Corrupts registers:
	44	; AX, BX, CX, DX
	45	;--------------------------------------------------------------------
	46	ParseFormatSpecifier:
	47	call ReadCharacterAndTestForNull
	48	call Char_IsDecimalDigitInAL
[101]	49	jc SHORT ParsePlaceholderSizeDigitFromALtoCX
[44]	50	call GetFormatSpecifierParserToAX
	51	call ax ; Parser function
	52	dec bp
	53	dec bp ; SS:BP now points to next parameter
	54	test cx, cx
	55	jnz SHORT PrependOrAppendSpaces
[101]	56	ReturnFromFormat:
[44]	57	ret
	58
	59	;--------------------------------------------------------------------
[101]	60	; ParsePlaceholderSizeDigitFromALtoCX
[44]	61	; Parameters:
	62	; AL: Digit character from format string
	63	; CX: Current placeholder size
	64	; DS: BDA segment (zero)
	65	; Returns:
	66	; CX: Current placeholder size
	67	; Jumps back to ParseFormatSpecifier
	68	; Corrupts registers:
	69	; AX
	70	;--------------------------------------------------------------------
	71	ALIGN JUMP_ALIGN
[101]	72	ParsePlaceholderSizeDigitFromALtoCX:
[44]	73	mov [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fpCursorPosition], di
	74	sub al, '0' ; Digit '0'...'9' to integer 0...9
	75	mov ah, cl ; Previous number parameter to AH
	76	aad ; AL += (AH * 10)
	77	mov cl, al ; Updated number parameter now in CX
	78	jmp SHORT ParseFormatSpecifier
	79
	80
	81	;--------------------------------------------------------------------
	82	; ReadCharacterAndTestForNull
	83	; Parameters:
[41]	84	; CS:SI: Pointer next character from string
	85	; Returns:
	86	; AL: Character from string
	87	; SI: Incremented to next character
	88	; ZF: Set if NULL, cleared if valid character
	89	; Corrupts registers:
	90	; Nothing
	91	;--------------------------------------------------------------------
	92	ALIGN JUMP_ALIGN
[44]	93	ReadCharacterAndTestForNull:
[41]	94	eSEG cs
	95	lodsb ; Load from CS:SI to AL
	96	test al, al ; NULL to end string?
	97	ret
	98
	99
	100	;--------------------------------------------------------------------
[44]	101	; GetFormatSpecifierParserToAX
[41]	102	; Parameters:
[44]	103	; AL: Format specifier character
[41]	104	; Returns:
[44]	105	; AX: Offset to parser function
[41]	106	; Corrupts registers:
[44]	107	; AX, BX
[41]	108	;--------------------------------------------------------------------
	109	ALIGN JUMP_ALIGN
[44]	110	GetFormatSpecifierParserToAX:
	111	mov bx, .rgcFormatCharToLookupIndex
	112	ALIGN JUMP_ALIGN
	113	.CheckForNextSpecifierParser:
	114	cmp al, [cs:bx]
	115	je SHORT .ConvertIndexToFunctionOffset
	116	inc bx
	117	cmp bx, .rgcFormatCharToLookupIndexEnd
	118	jb SHORT .CheckForNextSpecifierParser
	119	mov ax, c_FormatCharacter
	120	ret
	121	ALIGN JUMP_ALIGN
	122	.ConvertIndexToFunctionOffset:
	123	sub bx, .rgcFormatCharToLookupIndex
	124	shl bx, 1 ; Shift for WORD lookup
	125	mov ax, [cs:bx+.rgfnFormatSpecifierParser]
	126	ret
[41]	127
[44]	128	.rgcFormatCharToLookupIndex:
[134]	129	%ifndef EXCLUDE_FROM_XTIDE_UNIVERSAL_BIOS
[44]	130	db "aAduxsSct-+%"
[134]	131	%else
	132	db "Auxsc-" ; Required by XTIDE Universal BIOS
	133	%endif
[44]	134	.rgcFormatCharToLookupIndexEnd:
	135	ALIGN WORD_ALIGN
	136	.rgfnFormatSpecifierParser:
[134]	137	%ifndef EXCLUDE_FROM_XTIDE_UNIVERSAL_BIOS
[44]	138	dw a_FormatAttributeForNextCharacter
[134]	139	%endif
[44]	140	dw A_FormatAttributeForRemainingString
[134]	141	%ifndef EXCLUDE_FROM_XTIDE_UNIVERSAL_BIOS
[44]	142	dw d_FormatSignedDecimalWord
[134]	143	%endif
[44]	144	dw u_FormatUnsignedDecimalWord
	145	dw x_FormatHexadecimalWord
	146	dw s_FormatStringFromSegmentCS
[134]	147	%ifndef EXCLUDE_FROM_XTIDE_UNIVERSAL_BIOS
[44]	148	dw S_FormatStringFromFarPointer
[134]	149	%endif
[44]	150	dw c_FormatCharacter
[134]	151	%ifndef EXCLUDE_FROM_XTIDE_UNIVERSAL_BIOS
[44]	152	dw t_FormatRepeatCharacter
[134]	153	%endif
[44]	154	dw PrepareToPrependParameterWithSpaces
[134]	155	%ifndef EXCLUDE_FROM_XTIDE_UNIVERSAL_BIOS
[44]	156	dw PrepareToAppendSpacesAfterParameter
	157	dw percent_FormatPercent
[134]	158	%endif
[41]	159
[44]	160
[41]	161	;--------------------------------------------------------------------
[44]	162	; PrependOrAppendSpaces
[41]	163	; Parameters:
[44]	164	; CX: Minimum length for format specifier in characters
[41]	165	; DS: BDA segment (zero)
	166	; ES:DI: Ptr to cursor location in video RAM
	167	; Returns:
[44]	168	; Nothing
[41]	169	; Corrupts registers:
	170	; AX, BX, CX, DX
	171	;--------------------------------------------------------------------
	172	ALIGN JUMP_ALIGN
[44]	173	PrependOrAppendSpaces:
	174	mov ax, di
	175	sub ax, [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fpCursorPosition]
	176	test cx, cx
	177	js SHORT .PrependWithSpaces
	178	; Fall to .AppendSpaces
[41]	179
	180	;--------------------------------------------------------------------
[44]	181	; .AppendSpaces
[41]	182	; Parameters:
[44]	183	; AX: Number of format parameter BYTEs printed
	184	; CX: Minimum length for format specifier in characters
[41]	185	; DS: BDA segment (zero)
	186	; ES:DI: Ptr to cursor location in video RAM
	187	; Returns:
[44]	188	; Nothing
[41]	189	; Corrupts registers:
[44]	190	; AX, CX, DX
[41]	191	;--------------------------------------------------------------------
[44]	192	.AppendSpaces:
	193	call DisplayContext_GetCharacterOffsetToAXfromByteOffsetInAX
	194	sub cx, ax
	195	jle SHORT .NothingToAppendOrPrepend
[41]	196	mov al, ' '
[44]	197	jmp DisplayPrint_RepeatCharacterFromALwithCountInCX
[41]	198
	199	;--------------------------------------------------------------------
[44]	200	; .PrependWithSpaces
[41]	201	; Parameters:
[44]	202	; AX: Number of format parameter BYTEs printed
	203	; CX: Negative minimum length for format specifier in characters
[41]	204	; DS: BDA segment (zero)
	205	; ES:DI: Ptr to cursor location in video RAM
	206	; Returns:
[44]	207	; Nothing
[41]	208	; Corrupts registers:
[44]	209	; AX, BX, CX, DX
[41]	210	;--------------------------------------------------------------------
	211	ALIGN JUMP_ALIGN
[44]	212	.PrependWithSpaces:
	213	xchg ax, cx
	214	neg ax
	215	call DisplayContext_GetByteOffsetToAXfromCharacterOffsetInAX
	216	sub ax, cx ; AX = BYTEs to prepend, CX = BYTEs to move
	217	jle SHORT .NothingToAppendOrPrepend
[41]	218
[47]	219	std
	220	push si
[41]	221
[47]	222	lea si, [di-1] ; SI = Offset to last byte formatted
	223	add di, ax ; DI = Cursor location after preceeding completed
	224	push di
	225	dec di ; DI = Offset where to move last byte formatted
	226	xchg bx, ax ; BX = BYTEs to prepend
[48]	227	call .ReverseCopyCXbytesFromESSItoESDI
[47]	228	xchg ax, bx
	229	call .ReversePrintAXspacesStartingFromESDI
	230
	231	pop di
	232	pop si
	233	cld ; Restore DF
	234	.NothingToAppendOrPrepend:
	235	ret
	236
	237	;--------------------------------------------------------------------
[48]	238	; .ReverseCopyCXbytesFromESSItoESDI
[47]	239	; Parameters:
[48]	240	; CX: Number of bytes to copy
[47]	241	; DS: BDA segment (zero)
[48]	242	; ES:SI: Ptr to old location
	243	; ES:DI: Ptr to new location
[47]	244	; Returns:
[48]	245	; DI: Updated to before last character copied
[47]	246	; Corrupts registers:
	247	; AX, CX, DX, SI
	248	;--------------------------------------------------------------------
	249	ALIGN JUMP_ALIGN
[48]	250	.ReverseCopyCXbytesFromESSItoESDI:
	251	test BYTE [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bFlags], FLG_CONTEXT_ATTRIBUTES
	252	jz SHORT .CopyWithoutDisplayProcessing
[47]	253
[48]	254	WAIT_RETRACE_IF_NECESSARY_THEN rep movsb
	255	dec di ; Point to preceeding character instead of attribute
	256	ret
	257	ALIGN JUMP_ALIGN
	258	.CopyWithoutDisplayProcessing:
[44]	259	eSEG_STR rep, es, movsb
[47]	260	ret
	261
	262	;--------------------------------------------------------------------
	263	; .ReversePrintAXspacesStartingFromESDI
	264	; Parameters:
	265	; AX: Number of spaces to print
	266	; DS: BDA segment (zero)
	267	; ES:DI: Ptr to destination in video RAM
	268	; Returns:
	269	; DI: Updated
	270	; Corrupts registers:
	271	; AX, CX, DX
	272	ALIGN JUMP_ALIGN
	273	.ReversePrintAXspacesStartingFromESDI:
[44]	274	call DisplayContext_GetCharacterOffsetToAXfromByteOffsetInAX
	275	xchg cx, ax ; CX = Spaces to prepend
	276	mov al, ' '
[47]	277	jmp DisplayPrint_RepeatCharacterFromALwithCountInCX
[44]	278
	279
	280
	281	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
	282	; Formatting functions
[41]	283	; Parameters:
	284	; DS: BDA segment (zero)
[44]	285	; SS:BP: Pointer to next format parameter (-=2 updates to next parameter)
[41]	286	; ES:DI: Ptr to cursor location in video RAM
	287	; Returns:
[44]	288	; SS:BP: Points to last WORD parameter used
[41]	289	; Corrupts registers:
	290	; AX, BX, DX
[44]	291	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
[134]	292	%ifndef EXCLUDE_FROM_XTIDE_UNIVERSAL_BIOS
[41]	293	ALIGN JUMP_ALIGN
[44]	294	a_FormatAttributeForNextCharacter:
[41]	295	mov bl, [bp]
	296	xchg bl, [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bAttribute]
[44]	297	push bx
	298	push cx
	299	push di
	300	call DisplayFormat_ParseCharacters ; Recursive call
	301	pop WORD [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fpCursorPosition]
	302	pop cx
	303	pop bx
[41]	304	mov [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bAttribute], bl
[44]	305	ret
[134]	306	%endif
[41]	307
	308	ALIGN JUMP_ALIGN
[44]	309	A_FormatAttributeForRemainingString:
[41]	310	mov al, [bp]
	311	mov [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bAttribute], al
[44]	312	ret
[41]	313
[134]	314	%ifndef EXCLUDE_FROM_XTIDE_UNIVERSAL_BIOS
[41]	315	ALIGN JUMP_ALIGN
[44]	316	d_FormatSignedDecimalWord:
[41]	317	mov ax, [bp]
[44]	318	mov bx, 10
	319	jmp DisplayPrint_SignedWordFromAXWithBaseInBX
[134]	320	%endif
[41]	321
	322	ALIGN JUMP_ALIGN
[44]	323	u_FormatUnsignedDecimalWord:
[41]	324	mov ax, [bp]
	325	mov bx, 10
[44]	326	jmp DisplayPrint_WordFromAXWithBaseInBX
[41]	327
	328	ALIGN JUMP_ALIGN
[44]	329	x_FormatHexadecimalWord:
[41]	330	mov ax, [bp]
	331	mov bx, 16
	332	call DisplayPrint_WordFromAXWithBaseInBX
	333	mov al, 'h'
[44]	334	jmp DisplayPrint_CharacterFromAL
[41]	335
	336	ALIGN JUMP_ALIGN
[44]	337	s_FormatStringFromSegmentCS:
[41]	338	xchg si, [bp]
	339	call DisplayPrint_NullTerminatedStringFromCSSI
[44]	340	mov si, [bp]
	341	ret
[41]	342
[134]	343	%ifndef EXCLUDE_FROM_XTIDE_UNIVERSAL_BIOS
[41]	344	ALIGN JUMP_ALIGN
[44]	345	S_FormatStringFromFarPointer:
	346	mov bx, [bp-2]
[41]	347	xchg si, [bp]
	348	call DisplayPrint_NullTerminatedStringFromBXSI
[44]	349	mov si, [bp]
	350	dec bp
	351	dec bp
	352	ret
[134]	353	%endif
[41]	354
	355	ALIGN JUMP_ALIGN
[44]	356	c_FormatCharacter:
[41]	357	mov al, [bp]
[44]	358	jmp DisplayPrint_CharacterFromAL
[41]	359
[134]	360	%ifndef EXCLUDE_FROM_XTIDE_UNIVERSAL_BIOS
[41]	361	ALIGN JUMP_ALIGN
[44]	362	t_FormatRepeatCharacter:
	363	push cx
[41]	364	mov cx, [bp-2]
	365	mov al, [bp]
	366	call DisplayPrint_RepeatCharacterFromALwithCountInCX
[44]	367	pop cx
	368	dec bp
	369	dec bp
	370	ret
[41]	371
	372	ALIGN JUMP_ALIGN
[44]	373	percent_FormatPercent:
[41]	374	mov al, '%'
[44]	375	jmp DisplayPrint_CharacterFromAL
[134]	376	%endif
[41]	377
	378	ALIGN JUMP_ALIGN
[44]	379	PrepareToPrependParameterWithSpaces:
	380	neg cx
	381	; Fall to PrepareToAppendSpacesAfterParameter
[41]	382
	383	ALIGN JUMP_ALIGN
[44]	384	PrepareToAppendSpacesAfterParameter:
	385	add sp, BYTE 2 ; Remove return offset
	386	jmp ParseFormatSpecifier

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