Context Navigation

source: xtideuniversalbios/trunk/Assembly_Library/Src/Display/DisplayFormat.asm @ 48

Last change on this file since 48 was 48, checked in by aitotat, 14 years ago
Changes to Assembly Library: Added functions to clear Menu Title and Information areas. Implemented automatic line change when writing Menu Title and Information areas. CGA snow related functions have been moved to CgaSnow.asm. Keyboard input functions no longer produce beep for backspace.
File size: 10.5 KB

Rev	Line
[41]	1	; File name : DisplayFormat.asm
	2	; Project name : Assembly Library
	3	; Created date : 29.6.2010
[48]	4	; Last update : 8.10.2010
[41]	5	; Author : Tomi Tilli
	6	; Description : Functions for displaying formatted strings.
	7
	8	; Section containing code
	9	SECTION .text
	10
	11	;--------------------------------------------------------------------
	12	; DisplayFormat_ParseCharacters
	13	; Parameters:
	14	; DS: BDA segment (zero)
[44]	15	; SS:BP: Pointer to first format parameter (-=2 updates to next parameter)
[41]	16	; CS:SI: Pointer to string to format
	17	; ES:DI: Ptr to cursor location in video RAM
	18	; Returns:
[44]	19	; CS:SI: Ptr to end of format string (ptr to one past NULL)
[41]	20	; DI: Updated offset to video RAM
	21	; Corrupts registers:
[44]	22	; AX, BX, CX, DX, BP
[41]	23	;--------------------------------------------------------------------
	24	ALIGN JUMP_ALIGN
	25	DisplayFormat_ParseCharacters:
[44]	26	call ReadCharacterAndTestForNull
	27	jz SHORT .QuitCharacterParsing
	28
	29	ePUSH_T cx, DisplayFormat_ParseCharacters ; Return address
	30	xor cx, cx ; Initial placeholder size
	31	cmp al, '%' ; Format specifier?
	32	je SHORT ParseFormatSpecifier
	33	jmp DisplayPrint_CharacterFromAL
	34
[41]	35	ALIGN JUMP_ALIGN
[44]	36	.QuitCharacterParsing:
[41]	37	ret
	38
[44]	39
[41]	40	;--------------------------------------------------------------------
[44]	41	; ParseFormatSpecifier
[41]	42	; Parameters:
[44]	43	; CX: Placeholder size
	44	; DS: BDA segment (zero)
	45	; SS:BP: Pointer to first format parameter (-=2 for next parameter)
	46	; CS:SI: Pointer to string to format
	47	; ES:DI: Ptr to cursor location in video RAM
	48	; Returns:
	49	; SI: Updated to first unparsed character
	50	; DI: Updated offset to video RAM
	51	; BP: Updated to next format parameter
	52	; Corrupts registers:
	53	; AX, BX, CX, DX
	54	;--------------------------------------------------------------------
	55	ALIGN JUMP_ALIGN
	56	ParseFormatSpecifier:
	57	call ReadCharacterAndTestForNull
	58	call Char_IsDecimalDigitInAL
	59	jc SHORT .ParsePlaceholderSizeDigitFromALtoCX
	60	call GetFormatSpecifierParserToAX
	61	call ax ; Parser function
	62	dec bp
	63	dec bp ; SS:BP now points to next parameter
	64	test cx, cx
	65	jnz SHORT PrependOrAppendSpaces
	66	ret
	67
	68	;--------------------------------------------------------------------
	69	; .ParsePlaceholderSizeDigitFromALtoCX
	70	; Parameters:
	71	; AL: Digit character from format string
	72	; CX: Current placeholder size
	73	; DS: BDA segment (zero)
	74	; Returns:
	75	; CX: Current placeholder size
	76	; Jumps back to ParseFormatSpecifier
	77	; Corrupts registers:
	78	; AX
	79	;--------------------------------------------------------------------
	80	ALIGN JUMP_ALIGN
	81	.ParsePlaceholderSizeDigitFromALtoCX:
	82	mov [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fpCursorPosition], di
	83	sub al, '0' ; Digit '0'...'9' to integer 0...9
	84	mov ah, cl ; Previous number parameter to AH
	85	aad ; AL += (AH * 10)
	86	mov cl, al ; Updated number parameter now in CX
	87	jmp SHORT ParseFormatSpecifier
	88
	89
	90	;--------------------------------------------------------------------
	91	; ReadCharacterAndTestForNull
	92	; Parameters:
[41]	93	; CS:SI: Pointer next character from string
	94	; Returns:
	95	; AL: Character from string
	96	; SI: Incremented to next character
	97	; ZF: Set if NULL, cleared if valid character
	98	; Corrupts registers:
	99	; Nothing
	100	;--------------------------------------------------------------------
	101	ALIGN JUMP_ALIGN
[44]	102	ReadCharacterAndTestForNull:
[41]	103	eSEG cs
	104	lodsb ; Load from CS:SI to AL
	105	test al, al ; NULL to end string?
	106	ret
	107
	108
	109	;--------------------------------------------------------------------
[44]	110	; GetFormatSpecifierParserToAX
[41]	111	; Parameters:
[44]	112	; AL: Format specifier character
[41]	113	; Returns:
[44]	114	; AX: Offset to parser function
[41]	115	; Corrupts registers:
[44]	116	; AX, BX
[41]	117	;--------------------------------------------------------------------
	118	ALIGN JUMP_ALIGN
[44]	119	GetFormatSpecifierParserToAX:
	120	mov bx, .rgcFormatCharToLookupIndex
	121	ALIGN JUMP_ALIGN
	122	.CheckForNextSpecifierParser:
	123	cmp al, [cs:bx]
	124	je SHORT .ConvertIndexToFunctionOffset
	125	inc bx
	126	cmp bx, .rgcFormatCharToLookupIndexEnd
	127	jb SHORT .CheckForNextSpecifierParser
	128	mov ax, c_FormatCharacter
	129	ret
	130	ALIGN JUMP_ALIGN
	131	.ConvertIndexToFunctionOffset:
	132	sub bx, .rgcFormatCharToLookupIndex
	133	shl bx, 1 ; Shift for WORD lookup
	134	mov ax, [cs:bx+.rgfnFormatSpecifierParser]
	135	ret
[41]	136
[44]	137	.rgcFormatCharToLookupIndex:
	138	db "aAduxsSct-+%"
	139	.rgcFormatCharToLookupIndexEnd:
	140	ALIGN WORD_ALIGN
	141	.rgfnFormatSpecifierParser:
	142	dw a_FormatAttributeForNextCharacter
	143	dw A_FormatAttributeForRemainingString
	144	dw d_FormatSignedDecimalWord
	145	dw u_FormatUnsignedDecimalWord
	146	dw x_FormatHexadecimalWord
	147	dw s_FormatStringFromSegmentCS
	148	dw S_FormatStringFromFarPointer
	149	dw c_FormatCharacter
	150	dw t_FormatRepeatCharacter
	151	dw PrepareToPrependParameterWithSpaces
	152	dw PrepareToAppendSpacesAfterParameter
	153	dw percent_FormatPercent
[41]	154
[44]	155
[41]	156	;--------------------------------------------------------------------
[44]	157	; PrependOrAppendSpaces
[41]	158	; Parameters:
[44]	159	; CX: Minimum length for format specifier in characters
[41]	160	; DS: BDA segment (zero)
	161	; ES:DI: Ptr to cursor location in video RAM
	162	; Returns:
[44]	163	; Nothing
[41]	164	; Corrupts registers:
	165	; AX, BX, CX, DX
	166	;--------------------------------------------------------------------
	167	ALIGN JUMP_ALIGN
[44]	168	PrependOrAppendSpaces:
	169	mov ax, di
	170	sub ax, [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fpCursorPosition]
	171	test cx, cx
	172	js SHORT .PrependWithSpaces
	173	; Fall to .AppendSpaces
[41]	174
	175	;--------------------------------------------------------------------
[44]	176	; .AppendSpaces
[41]	177	; Parameters:
[44]	178	; AX: Number of format parameter BYTEs printed
	179	; CX: Minimum length for format specifier in characters
[41]	180	; DS: BDA segment (zero)
	181	; ES:DI: Ptr to cursor location in video RAM
	182	; Returns:
[44]	183	; Nothing
[41]	184	; Corrupts registers:
[44]	185	; AX, CX, DX
[41]	186	;--------------------------------------------------------------------
[44]	187	.AppendSpaces:
	188	call DisplayContext_GetCharacterOffsetToAXfromByteOffsetInAX
	189	sub cx, ax
	190	jle SHORT .NothingToAppendOrPrepend
[41]	191	mov al, ' '
[44]	192	jmp DisplayPrint_RepeatCharacterFromALwithCountInCX
[41]	193
	194	;--------------------------------------------------------------------
[44]	195	; .PrependWithSpaces
[41]	196	; Parameters:
[44]	197	; AX: Number of format parameter BYTEs printed
	198	; CX: Negative minimum length for format specifier in characters
[41]	199	; DS: BDA segment (zero)
	200	; ES:DI: Ptr to cursor location in video RAM
	201	; Returns:
[44]	202	; Nothing
[41]	203	; Corrupts registers:
[44]	204	; AX, BX, CX, DX
[41]	205	;--------------------------------------------------------------------
	206	ALIGN JUMP_ALIGN
[44]	207	.PrependWithSpaces:
	208	xchg ax, cx
	209	neg ax
	210	call DisplayContext_GetByteOffsetToAXfromCharacterOffsetInAX
	211	sub ax, cx ; AX = BYTEs to prepend, CX = BYTEs to move
	212	jle SHORT .NothingToAppendOrPrepend
[41]	213
[47]	214	std
	215	push si
[41]	216
[47]	217	lea si, [di-1] ; SI = Offset to last byte formatted
	218	add di, ax ; DI = Cursor location after preceeding completed
	219	push di
	220	dec di ; DI = Offset where to move last byte formatted
	221	xchg bx, ax ; BX = BYTEs to prepend
[48]	222	call .ReverseCopyCXbytesFromESSItoESDI
[47]	223	xchg ax, bx
	224	call .ReversePrintAXspacesStartingFromESDI
	225
	226	pop di
	227	pop si
	228	cld ; Restore DF
	229	.NothingToAppendOrPrepend:
	230	ret
	231
	232	;--------------------------------------------------------------------
[48]	233	; .ReverseCopyCXbytesFromESSItoESDI
[47]	234	; Parameters:
[48]	235	; CX: Number of bytes to copy
[47]	236	; DS: BDA segment (zero)
[48]	237	; ES:SI: Ptr to old location
	238	; ES:DI: Ptr to new location
[47]	239	; Returns:
[48]	240	; DI: Updated to before last character copied
[47]	241	; Corrupts registers:
	242	; AX, CX, DX, SI
	243	;--------------------------------------------------------------------
	244	ALIGN JUMP_ALIGN
[48]	245	.ReverseCopyCXbytesFromESSItoESDI:
	246	test BYTE [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bFlags], FLG_CONTEXT_ATTRIBUTES
	247	jz SHORT .CopyWithoutDisplayProcessing
[47]	248
[48]	249	WAIT_RETRACE_IF_NECESSARY_THEN rep movsb
	250	dec di ; Point to preceeding character instead of attribute
	251	ret
	252	ALIGN JUMP_ALIGN
	253	.CopyWithoutDisplayProcessing:
[44]	254	eSEG_STR rep, es, movsb
[47]	255	ret
	256
	257	;--------------------------------------------------------------------
	258	; .ReversePrintAXspacesStartingFromESDI
	259	; Parameters:
	260	; AX: Number of spaces to print
	261	; DS: BDA segment (zero)
	262	; ES:DI: Ptr to destination in video RAM
	263	; Returns:
	264	; DI: Updated
	265	; Corrupts registers:
	266	; AX, CX, DX
	267	ALIGN JUMP_ALIGN
	268	.ReversePrintAXspacesStartingFromESDI:
[44]	269	call DisplayContext_GetCharacterOffsetToAXfromByteOffsetInAX
	270	xchg cx, ax ; CX = Spaces to prepend
	271	mov al, ' '
[47]	272	jmp DisplayPrint_RepeatCharacterFromALwithCountInCX
[44]	273
	274
	275
	276	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
	277	; Formatting functions
[41]	278	; Parameters:
	279	; DS: BDA segment (zero)
[44]	280	; SS:BP: Pointer to next format parameter (-=2 updates to next parameter)
[41]	281	; ES:DI: Ptr to cursor location in video RAM
	282	; Returns:
[44]	283	; SS:BP: Points to last WORD parameter used
[41]	284	; Corrupts registers:
	285	; AX, BX, DX
[44]	286	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
[41]	287	ALIGN JUMP_ALIGN
[44]	288	a_FormatAttributeForNextCharacter:
[41]	289	mov bl, [bp]
	290	xchg bl, [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bAttribute]
[44]	291	push bx
	292	push cx
	293	push di
	294	call DisplayFormat_ParseCharacters ; Recursive call
	295	pop WORD [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.fpCursorPosition]
	296	pop cx
	297	pop bx
[41]	298	mov [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bAttribute], bl
[44]	299	ret
[41]	300
	301	ALIGN JUMP_ALIGN
[44]	302	A_FormatAttributeForRemainingString:
[41]	303	mov al, [bp]
	304	mov [VIDEO_BDA.displayContext+DISPLAY_CONTEXT.bAttribute], al
[44]	305	ret
[41]	306
	307	ALIGN JUMP_ALIGN
[44]	308	d_FormatSignedDecimalWord:
[41]	309	mov ax, [bp]
[44]	310	mov bx, 10
	311	jmp DisplayPrint_SignedWordFromAXWithBaseInBX
[41]	312
	313	ALIGN JUMP_ALIGN
[44]	314	u_FormatUnsignedDecimalWord:
[41]	315	mov ax, [bp]
	316	mov bx, 10
[44]	317	jmp DisplayPrint_WordFromAXWithBaseInBX
[41]	318
	319	ALIGN JUMP_ALIGN
[44]	320	x_FormatHexadecimalWord:
[41]	321	mov ax, [bp]
	322	mov bx, 16
	323	call DisplayPrint_WordFromAXWithBaseInBX
	324	mov al, 'h'
[44]	325	jmp DisplayPrint_CharacterFromAL
[41]	326
	327	ALIGN JUMP_ALIGN
[44]	328	s_FormatStringFromSegmentCS:
[41]	329	xchg si, [bp]
	330	call DisplayPrint_NullTerminatedStringFromCSSI
[44]	331	mov si, [bp]
	332	ret
[41]	333
	334	ALIGN JUMP_ALIGN
[44]	335	S_FormatStringFromFarPointer:
	336	mov bx, [bp-2]
[41]	337	xchg si, [bp]
	338	call DisplayPrint_NullTerminatedStringFromBXSI
[44]	339	mov si, [bp]
	340	dec bp
	341	dec bp
	342	ret
[41]	343
	344	ALIGN JUMP_ALIGN
[44]	345	c_FormatCharacter:
[41]	346	mov al, [bp]
[44]	347	jmp DisplayPrint_CharacterFromAL
[41]	348
	349	ALIGN JUMP_ALIGN
[44]	350	t_FormatRepeatCharacter:
	351	push cx
[41]	352	mov cx, [bp-2]
	353	mov al, [bp]
	354	call DisplayPrint_RepeatCharacterFromALwithCountInCX
[44]	355	pop cx
	356	dec bp
	357	dec bp
	358	ret
[41]	359
	360	ALIGN JUMP_ALIGN
[44]	361	percent_FormatPercent:
[41]	362	mov al, '%'
[44]	363	jmp DisplayPrint_CharacterFromAL
[41]	364
	365	ALIGN JUMP_ALIGN
[44]	366	PrepareToPrependParameterWithSpaces:
	367	neg cx
	368	; Fall to PrepareToAppendSpacesAfterParameter
[41]	369
	370	ALIGN JUMP_ALIGN
[44]	371	PrepareToAppendSpacesAfterParameter:
	372	add sp, BYTE 2 ; Remove return offset
	373	jmp ParseFormatSpecifier

Note: See TracBrowser for help on using the repository browser.

Download in other formats: