return (0);		}	} else					/* 1d encoding */		EncoderState(tif)->refline = NULL;	return (1);}/* * CCITT Group 3 FAX Encoding. */#define	Fax3FlushBits(tif, sp) {				\	if ((tif)->tif_rawcc >= (tif)->tif_rawdatasize)		\		(void) TIFFFlushData1(tif);			\	*(tif)->tif_rawcp++ = (tidataval_t) (sp)->data;		\	(tif)->tif_rawcc++;					\	(sp)->data = 0, (sp)->bit = 8;				\}#define	_FlushBits(tif) {					\	if ((tif)->tif_rawcc >= (tif)->tif_rawdatasize)		\		(void) TIFFFlushData1(tif);			\	*(tif)->tif_rawcp++ = (tidataval_t) data;		\	(tif)->tif_rawcc++;					\	data = 0, bit = 8;					\}static const int _msbmask[9] =    { 0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff };#define	_PutBits(tif, bits, length) {				\	while (length > bit) {					\		data |= bits >> (length - bit);			\		length -= bit;					\		_FlushBits(tif);				\	}							\	data |= (bits & _msbmask[length]) << (bit - length);	\	bit -= length;						\	if (bit == 0)						\		_FlushBits(tif);				\}	/* * Write a variable-length bit-value to * the output stream.  Values are * assumed to be at most 16 bits. */static voidFax3PutBits(TIFF* tif, unsigned int bits, unsigned int length){	Fax3CodecState* sp = EncoderState(tif);	unsigned int bit = sp->bit;	int data = sp->data;	_PutBits(tif, bits, length);	sp->data = data;	sp->bit = bit;}/* * Write a code to the output stream. */#define putcode(tif, te)	Fax3PutBits(tif, (te)->code, (te)->length)#ifdef FAX3_DEBUG#define	DEBUG_COLOR(w) (tab == TIFFFaxWhiteCodes ? w "W" : w "B")#define	DEBUG_PRINT(what,len) {						\    int t;								\    printf("%08X/%-2d: %s%5d\t", data, bit, DEBUG_COLOR(what), len);	\    for (t = length-1; t >= 0; t--)					\	putchar(code & (1<<t) ? '1' : '0');				\    putchar('\n');							\}#endif/* * Write the sequence of codes that describes * the specified span of zero's or one's.  The * appropriate table that holds the make-up and * terminating codes is supplied. */static voidputspan(TIFF* tif, int32 span, const tableentry* tab){	Fax3CodecState* sp = EncoderState(tif);	unsigned int bit = sp->bit;	int data = sp->data;	unsigned int code, length;	while (span >= 2624) {		const tableentry* te = &tab[63 + (2560>>6)];		code = te->code, length = te->length;#ifdef FAX3_DEBUG		DEBUG_PRINT("MakeUp", te->runlen);#endif		_PutBits(tif, code, length);		span -= te->runlen;	}	if (span >= 64) {		const tableentry* te = &tab[63 + (span>>6)];		assert(te->runlen == 64*(span>>6));		code = te->code, length = te->length;#ifdef FAX3_DEBUG		DEBUG_PRINT("MakeUp", te->runlen);#endif		_PutBits(tif, code, length);		span -= te->runlen;	}	code = tab[span].code, length = tab[span].length;#ifdef FAX3_DEBUG	DEBUG_PRINT("  Term", tab[span].runlen);#endif	_PutBits(tif, code, length);	sp->data = data;	sp->bit = bit;}/* * Write an EOL code to the output stream.  The zero-fill * logic for byte-aligning encoded scanlines is handled * here.  We also handle writing the tag bit for the next * scanline when doing 2d encoding. */static voidFax3PutEOL(TIFF* tif){	Fax3CodecState* sp = EncoderState(tif);	unsigned int bit = sp->bit;	int data = sp->data;	unsigned int code, length, tparm;	if (sp->b.groupoptions & GROUP3OPT_FILLBITS) {		/*		 * Force bit alignment so EOL will terminate on		 * a byte boundary.  That is, force the bit alignment		 * to 16-12 = 4 before putting out the EOL code.		 */		int align = 8 - 4;		if (align != sp->bit) {			if (align > sp->bit)				align = sp->bit + (8 - align);			else				align = sp->bit - align;			code = 0;			tparm=align; 			_PutBits(tif, 0, tparm);		}	}	code = EOL, length = 12;	if (is2DEncoding(sp))		code = (code<<1) | (sp->tag == G3_1D), length++;	_PutBits(tif, code, length);	sp->data = data;	sp->bit = bit;}/* * Reset encoding state at the start of a strip. */static intFax3PreEncode(TIFF* tif, tsample_t s){	Fax3CodecState* sp = EncoderState(tif);	(void) s;	assert(sp != NULL);	sp->bit = 8;	sp->data = 0;	sp->tag = G3_1D;	/*	 * This is necessary for Group 4; otherwise it isn't	 * needed because the first scanline of each strip ends	 * up being copied into the refline.	 */	if (sp->refline)		_TIFFmemset(sp->refline, 0x00, sp->b.rowbytes);	if (is2DEncoding(sp)) {		float res = tif->tif_dir.td_yresolution;		/*		 * The CCITT spec says that when doing 2d encoding, you		 * should only do it on K consecutive scanlines, where K		 * depends on the resolution of the image being encoded		 * (2 for <= 200 lpi, 4 for > 200 lpi).  Since the directory		 * code initializes td_yresolution to 0, this code will		 * select a K of 2 unless the YResolution tag is set		 * appropriately.  (Note also that we fudge a little here		 * and use 150 lpi to avoid problems with units conversion.)		 */		if (tif->tif_dir.td_resolutionunit == RESUNIT_CENTIMETER)			res *= 2.54f;		/* convert to inches */		sp->maxk = (res > 150 ? 4 : 2);		sp->k = sp->maxk-1;	} else		sp->k = sp->maxk = 0;	sp->line = 0;	return (1);}static const unsigned char zeroruns[256] = {    8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4,	/* 0x00 - 0x0f */    3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,	/* 0x10 - 0x1f */    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	/* 0x20 - 0x2f */    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	/* 0x30 - 0x3f */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x40 - 0x4f */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x50 - 0x5f */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x60 - 0x6f */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x70 - 0x7f */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x80 - 0x8f */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x90 - 0x9f */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xa0 - 0xaf */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xb0 - 0xbf */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xc0 - 0xcf */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xd0 - 0xdf */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xe0 - 0xef */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0xf0 - 0xff */};static const unsigned char oneruns[256] = {    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x00 - 0x0f */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x10 - 0x1f */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x20 - 0x2f */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x30 - 0x3f */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x40 - 0x4f */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x50 - 0x5f */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x60 - 0x6f */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,	/* 0x70 - 0x7f */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x80 - 0x8f */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0x90 - 0x9f */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0xa0 - 0xaf */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 0xb0 - 0xbf */    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	/* 0xc0 - 0xcf */    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,	/* 0xd0 - 0xdf */    3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,	/* 0xe0 - 0xef */    4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 7, 8,	/* 0xf0 - 0xff */};/* * On certain systems it pays to inline * the routines that find pixel spans. */#ifdef VAXCstatic	int32 find0span(unsigned char*, int32, int32);static	int32 find1span(unsigned char*, int32, int32);#pragma inline(find0span,find1span)#endif/* * Find a span of ones or zeros using the supplied * table.  The ``base'' of the bit string is supplied * along with the start+end bit indices. */static inline int32find0span(unsigned char* bp, int32 bs, int32 be){	int32 bits = be - bs;	int32 n, span;	bp += bs>>3;	/*	 * Check partial byte on lhs.	 */	if (bits > 0 && (n = (bs & 7))) {		span = zeroruns[(*bp << n) & 0xff];		if (span > 8-n)		/* table value too generous */			span = 8-n;		if (span > bits)	/* constrain span to bit range */			span = bits;		if (n+span < 8)		/* doesn't extend to edge of byte */			return (span);		bits -= span;		bp++;	} else		span = 0;	if (bits >= (int32)(2 * 8 * sizeof(long))) {		long* lp;		/*		 * Align to longword boundary and check longwords.		 */		while (!isAligned(bp, long)) {			if (*bp != 0x00)				return (span + zeroruns[*bp]);			span += 8, bits -= 8;			bp++;		}		lp = (long*) bp;		while ((bits >= (int32)(8 * sizeof(long))) && (0 == *lp)) {			span += 8*sizeof (long), bits -= 8*sizeof (long);			lp++;		}		bp = (unsigned char*) lp;	}	/*	 * Scan full bytes for all 0's.	 */	while (bits >= 8) {		if (*bp != 0x00)	/* end of run */			return (span + zeroruns[*bp]);		span += 8, bits -= 8;		bp++;	}	/*	 * Check partial byte on rhs.	 */	if (bits > 0) {		n = zeroruns[*bp];		span += (n > bits ? bits : n);	}	return (span);}static inline int32find1span(unsigned char* bp, int32 bs, int32 be){	int32 bits = be - bs;	int32 n, span;	bp += bs>>3;	/*	 * Check partial byte on lhs.	 */	if (bits > 0 && (n = (bs & 7))) {		span = oneruns[(*bp << n) & 0xff];		if (span > 8-n)		/* table value too generous */			span = 8-n;		if (span > bits)	/* constrain span to bit range */			span = bits;		if (n+span < 8)		/* doesn't extend to edge of byte */			return (span);		bits -= span;		bp++;	} else		span = 0;	if (bits >= (int32)(2 * 8 * sizeof(long))) {		long* lp;		/*		 * Align to longword boundary and check longwords.		 */		while (!isAligned(bp, long)) {			if (*bp != 0xff)				return (span + oneruns[*bp]);			span += 8, bits -= 8;			bp++;		}		lp = (long*) bp;		while ((bits >= (int32)(8 * sizeof(long))) && (~0 == *lp)) {			span += 8*sizeof (long), bits -= 8*sizeof (long);			lp++;		}		bp = (unsigned char*) lp;	}	/*	 * Scan full bytes for all 1's.	 */	while (bits >= 8) {		if (*bp != 0xff)	/* end of run */			return (span + oneruns[*bp]);		span += 8, bits -= 8;		bp++;	}	/*	 * Check partial byte on rhs.	 */	if (bits > 0) {		n = oneruns[*bp];		span += (n > bits ? bits : n);	}	return (span);}/* * Return the offset of the next bit in the range * [bs..be] that is different from the specified * color.  The end, be, is returned if no such bit * exists. */#define	finddiff(_cp, _bs, _be, _color)	\	(_bs + (_color ? find1span(_cp,_bs,_be) : find0span(_cp,_bs,_be)))/* * Like finddiff, but also check the starting bit * against the end in case start > end. */#define	finddiff2(_cp, _bs, _be, _color) \	(_bs < _be ? finddiff(_cp,_bs,_be,_color) : _be)/* * 1d-encode a row of pixels.  The encoding is * a sequence of all-white or all-black spans * of pixels encoded with Huffman codes. */static intFax3Encode1DRow(TIFF* tif, unsigned char* bp, uint32 bits){	Fax3CodecState* sp = EncoderState(tif);	int32 span;        uint32 bs = 0;	for (;;) {		span = find0span(bp, bs, bits);		/* white span */		putspan(tif, span, TIFFFaxWhiteCodes);		bs += span;		if (bs >= bits)			break;		span = find1span(bp, bs, bits);		/* black span */		putspan(tif, span, TIFFFaxBlackCodes);		bs += span;		if (bs >= bits)			break;	}	if (sp->b.mode & (FAXMODE_BYTEALIGN|FAXMODE_WORDALIGN)) {		if (sp->bit != 8)			/* byte-align */			Fax3FlushBits(tif, sp);		if ((sp->b.mode&FAXMODE_WORDALIGN) &&		    !isAligned(tif->tif_rawcp, uint16))			Fax3FlushBits(tif, sp);	}	return (1);}static const tableentry horizcode =    { 3, 0x1, 0 };	/* 001 */static const tableentry passcode =    { 4, 0x1, 0 };	/* 0001 */static const tableentry vcodes[7] = {    { 7, 0x03, 0 },	/* 0000 011 */    { 6, 0x03, 0 },	/* 0000 11 */    { 3, 0x03, 0 },	/* 011 */    { 1, 0x1, 0 },	/* 1 */    { 3, 0x2, 0 },	/* 010 */    { 6, 0x02, 0 },	/* 0000 10 */    { 7, 0x02, 0 }	/* 0000 010 */};/* * 2d-encode a row of pixels.  Consult the CCITT * documentation for the algorithm. */static intFax3Encode2DRow(TIFF* tif, unsigned char* bp, unsigned char* rp, uint32 bits){#define	PIXEL(buf,ix)	((((buf)[(ix)>>3]) >> (7-((ix)&7))) & 1)        uint32 a0 = 0;	uint32 a1 = (PIXEL(bp, 0) != 0 ? 0 : finddiff(bp, 0, bits, 0));	uint32 b1 = (PIXEL(rp, 0) != 0 ? 0 : finddiff(rp, 0, bits, 0));	uint32 a2, b2;	for (;;) {		b2 = finddiff2(rp, b1, bits, PIXEL(rp,b1));		if (b2 >= a1) {			int32 d = b1 - a1;			if (!(-3 <= d && d <= 3)) {	/* horizontal mode */				a2 = finddiff2(bp, a1, bits, PIXEL(bp,a1));				putcode(tif, &horizcode);				if (a0+a1 == 0 || PIXEL(bp, a0) == 0) {					putspan(tif, a1-a0, TIFFFaxWhiteCodes);					putspan(tif, a2-a1, TIFFFaxBlackCodes);				} else {					putspan(tif, a1-a0, TIFFFaxBlackCodes);					putspan(tif, a2-a1, TIFFFaxWhiteCodes);				}				a0 = a2;			} else {			/* vertical mode */				putcode(tif, &vcodes[d+3]);				a0 = a1;			}		} else {				/* pass mode */			putcode(tif, &passcode);			a0 = b2;		}		if (a0 >= bits)			break;		a1 = finddiff(bp, a0, bits, PIXEL(bp,a0));		b1 = finddiff(rp, a0, bits, !PIXEL(bp,a0));		b1 = finddiff(rp, b1, bits, PIXEL(bp,a0));	}	return (1);#undef PIXEL}/* * Encode a buffer of pixels. */static intFax3Encode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s){	Fax3CodecState* sp = EncoderState(tif);	(void) s;	while ((long)cc > 0) {		if ((sp->b.mode & FAXMODE_NOEOL) == 0)			Fax3PutEOL(tif);		if (is2DEncoding(sp)) {			if (sp->tag == G3_1D) {				if (!Fax3Encode1DRow(tif, bp, sp->b.rowpixels))					return (0);				sp->tag = G3_2D;			} else {				if (!Fax3Encode2DRow(tif, bp, sp->refline,                                                     sp->b.rowpixels))					return (0);				sp->k--;			}			if (sp->k == 0) {				sp->tag = G3_1D;				sp->k = sp->maxk-1;			} else				_TIFFmemcpy(sp->refline, bp, sp->b.rowbytes);		} else {			if (!Fax3Encode1DRow(tif, bp, sp->b.rowpixels))				return (0);		}		bp += sp->b.rowbytes;		cc -= sp->b.rowbytes;	}	return (1);}static intFax3PostEncode(TIFF* tif){	Fax3CodecState* sp = EncoderState(tif);	if (sp->bit != 8)		Fax3FlushBits(tif, sp);	return (1);}static void