1 /*
2  * Copyright (c) 1988-1997 Sam Leffler
3  * Copyright (c) 1991-1997 Silicon Graphics, Inc.
4  *
5  * Permission to use, copy, modify, distribute, and sell this software and
6  * its documentation for any purpose is hereby granted without fee, provided
7  * that (i) the above copyright notices and this permission notice appear in
8  * all copies of the software and related documentation, and (ii) the names of
9  * Sam Leffler and Silicon Graphics may not be used in any advertising or
10  * publicity relating to the software without the specific, prior written
11  * permission of Sam Leffler and Silicon Graphics.
12  *
13  * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
14  * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
15  * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
16  *
17  * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
18  * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
19  * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
20  * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
21  * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
22  * OF THIS SOFTWARE.
23  */
24 
25 /*
26  * TIFF Library.
27  *
28  * Predictor Tag Support (used by multiple codecs).
29  */
30 #include "tiffiop.h"
31 #include "tif_predict.h"
32 
33 #define	PredictorState(tif)	((TIFFPredictorState*) (tif)->tif_data)
34 
35 static int horAcc8(TIFF* tif, uint8* cp0, tmsize_t cc);
36 static int horAcc16(TIFF* tif, uint8* cp0, tmsize_t cc);
37 static int horAcc32(TIFF* tif, uint8* cp0, tmsize_t cc);
38 static int swabHorAcc16(TIFF* tif, uint8* cp0, tmsize_t cc);
39 static int swabHorAcc32(TIFF* tif, uint8* cp0, tmsize_t cc);
40 static int horDiff8(TIFF* tif, uint8* cp0, tmsize_t cc);
41 static int horDiff16(TIFF* tif, uint8* cp0, tmsize_t cc);
42 static int horDiff32(TIFF* tif, uint8* cp0, tmsize_t cc);
43 static int swabHorDiff16(TIFF* tif, uint8* cp0, tmsize_t cc);
44 static int swabHorDiff32(TIFF* tif, uint8* cp0, tmsize_t cc);
45 static int fpAcc(TIFF* tif, uint8* cp0, tmsize_t cc);
46 static int fpDiff(TIFF* tif, uint8* cp0, tmsize_t cc);
47 static int PredictorDecodeRow(TIFF* tif, uint8* op0, tmsize_t occ0, uint16 s);
48 static int PredictorDecodeTile(TIFF* tif, uint8* op0, tmsize_t occ0, uint16 s);
49 static int PredictorEncodeRow(TIFF* tif, uint8* bp, tmsize_t cc, uint16 s);
50 static int PredictorEncodeTile(TIFF* tif, uint8* bp0, tmsize_t cc0, uint16 s);
51 
52 static int
PredictorSetup(TIFF * tif)53 PredictorSetup(TIFF* tif)
54 {
55 	static const char module[] = "PredictorSetup";
56 
57 	TIFFPredictorState* sp = PredictorState(tif);
58 	TIFFDirectory* td = &tif->tif_dir;
59 
60 	switch (sp->predictor)		/* no differencing */
61 	{
62 		case PREDICTOR_NONE:
63 			return 1;
64 		case PREDICTOR_HORIZONTAL:
65 			if (td->td_bitspersample != 8
66 			    && td->td_bitspersample != 16
67 			    && td->td_bitspersample != 32) {
68 				TIFFErrorExt(tif->tif_clientdata, module,
69 				    "Horizontal differencing \"Predictor\" not supported with %d-bit samples",
70 				    td->td_bitspersample);
71 				return 0;
72 			}
73 			break;
74 		case PREDICTOR_FLOATINGPOINT:
75 			if (td->td_sampleformat != SAMPLEFORMAT_IEEEFP) {
76 				TIFFErrorExt(tif->tif_clientdata, module,
77 				    "Floating point \"Predictor\" not supported with %d data format",
78 				    td->td_sampleformat);
79 				return 0;
80 			}
81                         if (td->td_bitspersample != 16
82                             && td->td_bitspersample != 24
83                             && td->td_bitspersample != 32
84                             && td->td_bitspersample != 64) { /* Should 64 be allowed? */
85                                 TIFFErrorExt(tif->tif_clientdata, module,
86                                              "Floating point \"Predictor\" not supported with %d-bit samples",
87                                              td->td_bitspersample);
88 				return 0;
89                             }
90 			break;
91 		default:
92 			TIFFErrorExt(tif->tif_clientdata, module,
93 			    "\"Predictor\" value %d not supported",
94 			    sp->predictor);
95 			return 0;
96 	}
97 	sp->stride = (td->td_planarconfig == PLANARCONFIG_CONTIG ?
98 	    td->td_samplesperpixel : 1);
99 	/*
100 	 * Calculate the scanline/tile-width size in bytes.
101 	 */
102 	if (isTiled(tif))
103 		sp->rowsize = TIFFTileRowSize(tif);
104 	else
105 		sp->rowsize = TIFFScanlineSize(tif);
106 	if (sp->rowsize == 0)
107 		return 0;
108 
109 	return 1;
110 }
111 
112 static int
PredictorSetupDecode(TIFF * tif)113 PredictorSetupDecode(TIFF* tif)
114 {
115 	TIFFPredictorState* sp = PredictorState(tif);
116 	TIFFDirectory* td = &tif->tif_dir;
117 
118 	/* Note: when PredictorSetup() fails, the effets of setupdecode() */
119 	/* will not be "cancelled" so setupdecode() might be robust to */
120 	/* be called several times. */
121 	if (!(*sp->setupdecode)(tif) || !PredictorSetup(tif))
122 		return 0;
123 
124 	if (sp->predictor == 2) {
125 		switch (td->td_bitspersample) {
126 			case 8:  sp->decodepfunc = horAcc8; break;
127 			case 16: sp->decodepfunc = horAcc16; break;
128 			case 32: sp->decodepfunc = horAcc32; break;
129 		}
130 		/*
131 		 * Override default decoding method with one that does the
132 		 * predictor stuff.
133 		 */
134                 if( tif->tif_decoderow != PredictorDecodeRow )
135                 {
136                     sp->decoderow = tif->tif_decoderow;
137                     tif->tif_decoderow = PredictorDecodeRow;
138                     sp->decodestrip = tif->tif_decodestrip;
139                     tif->tif_decodestrip = PredictorDecodeTile;
140                     sp->decodetile = tif->tif_decodetile;
141                     tif->tif_decodetile = PredictorDecodeTile;
142                 }
143 
144 		/*
145 		 * If the data is horizontally differenced 16-bit data that
146 		 * requires byte-swapping, then it must be byte swapped before
147 		 * the accumulation step.  We do this with a special-purpose
148 		 * routine and override the normal post decoding logic that
149 		 * the library setup when the directory was read.
150 		 */
151 		if (tif->tif_flags & TIFF_SWAB) {
152 			if (sp->decodepfunc == horAcc16) {
153 				sp->decodepfunc = swabHorAcc16;
154 				tif->tif_postdecode = _TIFFNoPostDecode;
155             } else if (sp->decodepfunc == horAcc32) {
156 				sp->decodepfunc = swabHorAcc32;
157 				tif->tif_postdecode = _TIFFNoPostDecode;
158             }
159 		}
160 	}
161 
162 	else if (sp->predictor == 3) {
163 		sp->decodepfunc = fpAcc;
164 		/*
165 		 * Override default decoding method with one that does the
166 		 * predictor stuff.
167 		 */
168                 if( tif->tif_decoderow != PredictorDecodeRow )
169                 {
170                     sp->decoderow = tif->tif_decoderow;
171                     tif->tif_decoderow = PredictorDecodeRow;
172                     sp->decodestrip = tif->tif_decodestrip;
173                     tif->tif_decodestrip = PredictorDecodeTile;
174                     sp->decodetile = tif->tif_decodetile;
175                     tif->tif_decodetile = PredictorDecodeTile;
176                 }
177 		/*
178 		 * The data should not be swapped outside of the floating
179 		 * point predictor, the accumulation routine should return
180 		 * byres in the native order.
181 		 */
182 		if (tif->tif_flags & TIFF_SWAB) {
183 			tif->tif_postdecode = _TIFFNoPostDecode;
184 		}
185 		/*
186 		 * Allocate buffer to keep the decoded bytes before
187 		 * rearranging in the right order
188 		 */
189 	}
190 
191 	return 1;
192 }
193 
194 static int
PredictorSetupEncode(TIFF * tif)195 PredictorSetupEncode(TIFF* tif)
196 {
197 	TIFFPredictorState* sp = PredictorState(tif);
198 	TIFFDirectory* td = &tif->tif_dir;
199 
200 	if (!(*sp->setupencode)(tif) || !PredictorSetup(tif))
201 		return 0;
202 
203 	if (sp->predictor == 2) {
204 		switch (td->td_bitspersample) {
205 			case 8:  sp->encodepfunc = horDiff8; break;
206 			case 16: sp->encodepfunc = horDiff16; break;
207 			case 32: sp->encodepfunc = horDiff32; break;
208 		}
209 		/*
210 		 * Override default encoding method with one that does the
211 		 * predictor stuff.
212 		 */
213                 if( tif->tif_encoderow != PredictorEncodeRow )
214                 {
215                     sp->encoderow = tif->tif_encoderow;
216                     tif->tif_encoderow = PredictorEncodeRow;
217                     sp->encodestrip = tif->tif_encodestrip;
218                     tif->tif_encodestrip = PredictorEncodeTile;
219                     sp->encodetile = tif->tif_encodetile;
220                     tif->tif_encodetile = PredictorEncodeTile;
221                 }
222 
223                 /*
224                  * If the data is horizontally differenced 16-bit data that
225                  * requires byte-swapping, then it must be byte swapped after
226                  * the differentiation step.  We do this with a special-purpose
227                  * routine and override the normal post decoding logic that
228                  * the library setup when the directory was read.
229                  */
230                 if (tif->tif_flags & TIFF_SWAB) {
231                     if (sp->encodepfunc == horDiff16) {
232                             sp->encodepfunc = swabHorDiff16;
233                             tif->tif_postdecode = _TIFFNoPostDecode;
234                     } else if (sp->encodepfunc == horDiff32) {
235                             sp->encodepfunc = swabHorDiff32;
236                             tif->tif_postdecode = _TIFFNoPostDecode;
237                     }
238                 }
239         }
240 
241 	else if (sp->predictor == 3) {
242 		sp->encodepfunc = fpDiff;
243 		/*
244 		 * Override default encoding method with one that does the
245 		 * predictor stuff.
246 		 */
247                 if( tif->tif_encoderow != PredictorEncodeRow )
248                 {
249                     sp->encoderow = tif->tif_encoderow;
250                     tif->tif_encoderow = PredictorEncodeRow;
251                     sp->encodestrip = tif->tif_encodestrip;
252                     tif->tif_encodestrip = PredictorEncodeTile;
253                     sp->encodetile = tif->tif_encodetile;
254                     tif->tif_encodetile = PredictorEncodeTile;
255                 }
256 	}
257 
258 	return 1;
259 }
260 
261 #define REPEAT4(n, op)		\
262     switch (n) {		\
263     default: { \
264         tmsize_t i; for (i = n-4; i > 0; i--) { op; } }  /*-fallthrough*/  \
265     case 4:  op; /*-fallthrough*/ \
266     case 3:  op; /*-fallthrough*/ \
267     case 2:  op; /*-fallthrough*/ \
268     case 1:  op; /*-fallthrough*/ \
269     case 0:  ;			\
270     }
271 
272 /* Remarks related to C standard compliance in all below functions : */
273 /* - to avoid any undefined behaviour, we only operate on unsigned types */
274 /*   since the behaviour of "overflows" is defined (wrap over) */
275 /* - when storing into the byte stream, we explicitly mask with 0xff so */
276 /*   as to make icc -check=conversions happy (not necessary by the standard) */
277 
278 TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW
279 static int
horAcc8(TIFF * tif,uint8 * cp0,tmsize_t cc)280 horAcc8(TIFF* tif, uint8* cp0, tmsize_t cc)
281 {
282 	tmsize_t stride = PredictorState(tif)->stride;
283 
284 	unsigned char* cp = (unsigned char*) cp0;
285     if((cc%stride)!=0)
286     {
287         TIFFErrorExt(tif->tif_clientdata, "horAcc8",
288                      "%s", "(cc%stride)!=0");
289         return 0;
290     }
291 
292 	if (cc > stride) {
293 		/*
294 		 * Pipeline the most common cases.
295 		 */
296 		if (stride == 3)  {
297 			unsigned int cr = cp[0];
298 			unsigned int cg = cp[1];
299 			unsigned int cb = cp[2];
300 			cc -= 3;
301 			cp += 3;
302 			while (cc>0) {
303 				cp[0] = (unsigned char) ((cr += cp[0]) & 0xff);
304 				cp[1] = (unsigned char) ((cg += cp[1]) & 0xff);
305 				cp[2] = (unsigned char) ((cb += cp[2]) & 0xff);
306 				cc -= 3;
307 				cp += 3;
308 			}
309 		} else if (stride == 4)  {
310 			unsigned int cr = cp[0];
311 			unsigned int cg = cp[1];
312 			unsigned int cb = cp[2];
313 			unsigned int ca = cp[3];
314 			cc -= 4;
315 			cp += 4;
316 			while (cc>0) {
317 				cp[0] = (unsigned char) ((cr += cp[0]) & 0xff);
318 				cp[1] = (unsigned char) ((cg += cp[1]) & 0xff);
319 				cp[2] = (unsigned char) ((cb += cp[2]) & 0xff);
320 				cp[3] = (unsigned char) ((ca += cp[3]) & 0xff);
321 				cc -= 4;
322 				cp += 4;
323 			}
324 		} else  {
325 			cc -= stride;
326 			do {
327 				REPEAT4(stride, cp[stride] =
328 					(unsigned char) ((cp[stride] + *cp) & 0xff); cp++)
329 				cc -= stride;
330 			} while (cc>0);
331 		}
332 	}
333 	return 1;
334 }
335 
336 static int
swabHorAcc16(TIFF * tif,uint8 * cp0,tmsize_t cc)337 swabHorAcc16(TIFF* tif, uint8* cp0, tmsize_t cc)
338 {
339 	uint16* wp = (uint16*) cp0;
340 	tmsize_t wc = cc / 2;
341 
342         TIFFSwabArrayOfShort(wp, wc);
343         return horAcc16(tif, cp0, cc);
344 }
345 
346 TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW
347 static int
horAcc16(TIFF * tif,uint8 * cp0,tmsize_t cc)348 horAcc16(TIFF* tif, uint8* cp0, tmsize_t cc)
349 {
350 	tmsize_t stride = PredictorState(tif)->stride;
351 	uint16* wp = (uint16*) cp0;
352 	tmsize_t wc = cc / 2;
353 
354     if((cc%(2*stride))!=0)
355     {
356         TIFFErrorExt(tif->tif_clientdata, "horAcc16",
357                      "%s", "cc%(2*stride))!=0");
358         return 0;
359     }
360 
361 	if (wc > stride) {
362 		wc -= stride;
363 		do {
364 			REPEAT4(stride, wp[stride] = (uint16)(((unsigned int)wp[stride] + (unsigned int)wp[0]) & 0xffff); wp++)
365 			wc -= stride;
366 		} while (wc > 0);
367 	}
368 	return 1;
369 }
370 
371 static int
swabHorAcc32(TIFF * tif,uint8 * cp0,tmsize_t cc)372 swabHorAcc32(TIFF* tif, uint8* cp0, tmsize_t cc)
373 {
374 	uint32* wp = (uint32*) cp0;
375 	tmsize_t wc = cc / 4;
376 
377         TIFFSwabArrayOfLong(wp, wc);
378 	return horAcc32(tif, cp0, cc);
379 }
380 
381 TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW
382 static int
horAcc32(TIFF * tif,uint8 * cp0,tmsize_t cc)383 horAcc32(TIFF* tif, uint8* cp0, tmsize_t cc)
384 {
385 	tmsize_t stride = PredictorState(tif)->stride;
386 	uint32* wp = (uint32*) cp0;
387 	tmsize_t wc = cc / 4;
388 
389     if((cc%(4*stride))!=0)
390     {
391         TIFFErrorExt(tif->tif_clientdata, "horAcc32",
392                      "%s", "cc%(4*stride))!=0");
393         return 0;
394     }
395 
396 	if (wc > stride) {
397 		wc -= stride;
398 		do {
399 			REPEAT4(stride, wp[stride] += wp[0]; wp++)
400 			wc -= stride;
401 		} while (wc > 0);
402 	}
403 	return 1;
404 }
405 
406 /*
407  * Floating point predictor accumulation routine.
408  */
409 static int
fpAcc(TIFF * tif,uint8 * cp0,tmsize_t cc)410 fpAcc(TIFF* tif, uint8* cp0, tmsize_t cc)
411 {
412 	tmsize_t stride = PredictorState(tif)->stride;
413 	uint32 bps = tif->tif_dir.td_bitspersample / 8;
414 	tmsize_t wc = cc / bps;
415 	tmsize_t count = cc;
416 	uint8 *cp = (uint8 *) cp0;
417 	uint8 *tmp;
418 
419     if(cc%(bps*stride)!=0)
420     {
421         TIFFErrorExt(tif->tif_clientdata, "fpAcc",
422                      "%s", "cc%(bps*stride))!=0");
423         return 0;
424     }
425 
426     tmp = (uint8 *)_TIFFmalloc(cc);
427 	if (!tmp)
428 		return 0;
429 
430 	while (count > stride) {
431 		REPEAT4(stride, cp[stride] =
432                         (unsigned char) ((cp[stride] + cp[0]) & 0xff); cp++)
433 		count -= stride;
434 	}
435 
436 	_TIFFmemcpy(tmp, cp0, cc);
437 	cp = (uint8 *) cp0;
438 	for (count = 0; count < wc; count++) {
439 		uint32 byte;
440 		for (byte = 0; byte < bps; byte++) {
441 			#if WORDS_BIGENDIAN
442 			cp[bps * count + byte] = tmp[byte * wc + count];
443 			#else
444 			cp[bps * count + byte] =
445 				tmp[(bps - byte - 1) * wc + count];
446 			#endif
447 		}
448 	}
449 	_TIFFfree(tmp);
450     return 1;
451 }
452 
453 /*
454  * Decode a scanline and apply the predictor routine.
455  */
456 static int
PredictorDecodeRow(TIFF * tif,uint8 * op0,tmsize_t occ0,uint16 s)457 PredictorDecodeRow(TIFF* tif, uint8* op0, tmsize_t occ0, uint16 s)
458 {
459 	TIFFPredictorState *sp = PredictorState(tif);
460 
461 	assert(sp != NULL);
462 	assert(sp->decoderow != NULL);
463 	assert(sp->decodepfunc != NULL);
464 
465 	if ((*sp->decoderow)(tif, op0, occ0, s)) {
466 		return (*sp->decodepfunc)(tif, op0, occ0);
467 	} else
468 		return 0;
469 }
470 
471 /*
472  * Decode a tile/strip and apply the predictor routine.
473  * Note that horizontal differencing must be done on a
474  * row-by-row basis.  The width of a "row" has already
475  * been calculated at pre-decode time according to the
476  * strip/tile dimensions.
477  */
478 static int
PredictorDecodeTile(TIFF * tif,uint8 * op0,tmsize_t occ0,uint16 s)479 PredictorDecodeTile(TIFF* tif, uint8* op0, tmsize_t occ0, uint16 s)
480 {
481 	TIFFPredictorState *sp = PredictorState(tif);
482 
483 	assert(sp != NULL);
484 	assert(sp->decodetile != NULL);
485 
486 	if ((*sp->decodetile)(tif, op0, occ0, s)) {
487 		tmsize_t rowsize = sp->rowsize;
488 		assert(rowsize > 0);
489 		if((occ0%rowsize) !=0)
490         {
491             TIFFErrorExt(tif->tif_clientdata, "PredictorDecodeTile",
492                          "%s", "occ0%rowsize != 0");
493             return 0;
494         }
495 		assert(sp->decodepfunc != NULL);
496 		while (occ0 > 0) {
497 			if( !(*sp->decodepfunc)(tif, op0, rowsize) )
498                 return 0;
499 			occ0 -= rowsize;
500 			op0 += rowsize;
501 		}
502 		return 1;
503 	} else
504 		return 0;
505 }
506 
507 TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW
508 static int
horDiff8(TIFF * tif,uint8 * cp0,tmsize_t cc)509 horDiff8(TIFF* tif, uint8* cp0, tmsize_t cc)
510 {
511 	TIFFPredictorState* sp = PredictorState(tif);
512 	tmsize_t stride = sp->stride;
513 	unsigned char* cp = (unsigned char*) cp0;
514 
515     if((cc%stride)!=0)
516     {
517         TIFFErrorExt(tif->tif_clientdata, "horDiff8",
518                      "%s", "(cc%stride)!=0");
519         return 0;
520     }
521 
522 	if (cc > stride) {
523 		cc -= stride;
524 		/*
525 		 * Pipeline the most common cases.
526 		 */
527 		if (stride == 3) {
528 			unsigned int r1, g1, b1;
529 			unsigned int r2 = cp[0];
530 			unsigned int g2 = cp[1];
531 			unsigned  int b2 = cp[2];
532 			do {
533 				r1 = cp[3]; cp[3] = (unsigned char)((r1-r2)&0xff); r2 = r1;
534 				g1 = cp[4]; cp[4] = (unsigned char)((g1-g2)&0xff); g2 = g1;
535 				b1 = cp[5]; cp[5] = (unsigned char)((b1-b2)&0xff); b2 = b1;
536 				cp += 3;
537 			} while ((cc -= 3) > 0);
538 		} else if (stride == 4) {
539 			unsigned int r1, g1, b1, a1;
540 			unsigned int r2 = cp[0];
541 			unsigned int g2 = cp[1];
542 			unsigned int b2 = cp[2];
543 			unsigned int a2 = cp[3];
544 			do {
545 				r1 = cp[4]; cp[4] = (unsigned char)((r1-r2)&0xff); r2 = r1;
546 				g1 = cp[5]; cp[5] = (unsigned char)((g1-g2)&0xff); g2 = g1;
547 				b1 = cp[6]; cp[6] = (unsigned char)((b1-b2)&0xff); b2 = b1;
548 				a1 = cp[7]; cp[7] = (unsigned char)((a1-a2)&0xff); a2 = a1;
549 				cp += 4;
550 			} while ((cc -= 4) > 0);
551 		} else {
552 			cp += cc - 1;
553 			do {
554 				REPEAT4(stride, cp[stride] = (unsigned char)((cp[stride] - cp[0])&0xff); cp--)
555 			} while ((cc -= stride) > 0);
556 		}
557 	}
558 	return 1;
559 }
560 
561 TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW
562 static int
horDiff16(TIFF * tif,uint8 * cp0,tmsize_t cc)563 horDiff16(TIFF* tif, uint8* cp0, tmsize_t cc)
564 {
565 	TIFFPredictorState* sp = PredictorState(tif);
566 	tmsize_t stride = sp->stride;
567 	uint16 *wp = (uint16*) cp0;
568 	tmsize_t wc = cc/2;
569 
570     if((cc%(2*stride))!=0)
571     {
572         TIFFErrorExt(tif->tif_clientdata, "horDiff8",
573                      "%s", "(cc%(2*stride))!=0");
574         return 0;
575     }
576 
577 	if (wc > stride) {
578 		wc -= stride;
579 		wp += wc - 1;
580 		do {
581 			REPEAT4(stride, wp[stride] = (uint16)(((unsigned int)wp[stride] - (unsigned int)wp[0]) & 0xffff); wp--)
582 			wc -= stride;
583 		} while (wc > 0);
584 	}
585 	return 1;
586 }
587 
588 static int
swabHorDiff16(TIFF * tif,uint8 * cp0,tmsize_t cc)589 swabHorDiff16(TIFF* tif, uint8* cp0, tmsize_t cc)
590 {
591     uint16* wp = (uint16*) cp0;
592     tmsize_t wc = cc / 2;
593 
594     if( !horDiff16(tif, cp0, cc) )
595         return 0;
596 
597     TIFFSwabArrayOfShort(wp, wc);
598     return 1;
599 }
600 
601 TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW
602 static int
horDiff32(TIFF * tif,uint8 * cp0,tmsize_t cc)603 horDiff32(TIFF* tif, uint8* cp0, tmsize_t cc)
604 {
605 	TIFFPredictorState* sp = PredictorState(tif);
606 	tmsize_t stride = sp->stride;
607 	uint32 *wp = (uint32*) cp0;
608 	tmsize_t wc = cc/4;
609 
610     if((cc%(4*stride))!=0)
611     {
612         TIFFErrorExt(tif->tif_clientdata, "horDiff32",
613                      "%s", "(cc%(4*stride))!=0");
614         return 0;
615     }
616 
617 	if (wc > stride) {
618 		wc -= stride;
619 		wp += wc - 1;
620 		do {
621 			REPEAT4(stride, wp[stride] -= wp[0]; wp--)
622 			wc -= stride;
623 		} while (wc > 0);
624 	}
625 	return 1;
626 }
627 
628 static int
swabHorDiff32(TIFF * tif,uint8 * cp0,tmsize_t cc)629 swabHorDiff32(TIFF* tif, uint8* cp0, tmsize_t cc)
630 {
631     uint32* wp = (uint32*) cp0;
632     tmsize_t wc = cc / 4;
633 
634     if( !horDiff32(tif, cp0, cc) )
635         return 0;
636 
637     TIFFSwabArrayOfLong(wp, wc);
638     return 1;
639 }
640 
641 /*
642  * Floating point predictor differencing routine.
643  */
644 TIFF_NOSANITIZE_UNSIGNED_INT_OVERFLOW
645 static int
fpDiff(TIFF * tif,uint8 * cp0,tmsize_t cc)646 fpDiff(TIFF* tif, uint8* cp0, tmsize_t cc)
647 {
648 	tmsize_t stride = PredictorState(tif)->stride;
649 	uint32 bps = tif->tif_dir.td_bitspersample / 8;
650 	tmsize_t wc = cc / bps;
651 	tmsize_t count;
652 	uint8 *cp = (uint8 *) cp0;
653 	uint8 *tmp;
654 
655     if((cc%(bps*stride))!=0)
656     {
657         TIFFErrorExt(tif->tif_clientdata, "fpDiff",
658                      "%s", "(cc%(bps*stride))!=0");
659         return 0;
660     }
661 
662     tmp = (uint8 *)_TIFFmalloc(cc);
663 	if (!tmp)
664 		return 0;
665 
666 	_TIFFmemcpy(tmp, cp0, cc);
667 	for (count = 0; count < wc; count++) {
668 		uint32 byte;
669 		for (byte = 0; byte < bps; byte++) {
670 			#if WORDS_BIGENDIAN
671 			cp[byte * wc + count] = tmp[bps * count + byte];
672 			#else
673 			cp[(bps - byte - 1) * wc + count] =
674 				tmp[bps * count + byte];
675 			#endif
676 		}
677 	}
678 	_TIFFfree(tmp);
679 
680 	cp = (uint8 *) cp0;
681 	cp += cc - stride - 1;
682 	for (count = cc; count > stride; count -= stride)
683 		REPEAT4(stride, cp[stride] = (unsigned char)((cp[stride] - cp[0])&0xff); cp--)
684     return 1;
685 }
686 
687 static int
PredictorEncodeRow(TIFF * tif,uint8 * bp,tmsize_t cc,uint16 s)688 PredictorEncodeRow(TIFF* tif, uint8* bp, tmsize_t cc, uint16 s)
689 {
690 	TIFFPredictorState *sp = PredictorState(tif);
691 
692 	assert(sp != NULL);
693 	assert(sp->encodepfunc != NULL);
694 	assert(sp->encoderow != NULL);
695 
696 	/* XXX horizontal differencing alters user's data XXX */
697 	if( !(*sp->encodepfunc)(tif, bp, cc) )
698         return 0;
699 	return (*sp->encoderow)(tif, bp, cc, s);
700 }
701 
702 static int
PredictorEncodeTile(TIFF * tif,uint8 * bp0,tmsize_t cc0,uint16 s)703 PredictorEncodeTile(TIFF* tif, uint8* bp0, tmsize_t cc0, uint16 s)
704 {
705 	static const char module[] = "PredictorEncodeTile";
706 	TIFFPredictorState *sp = PredictorState(tif);
707         uint8 *working_copy;
708 	tmsize_t cc = cc0, rowsize;
709 	unsigned char* bp;
710         int result_code;
711 
712 	assert(sp != NULL);
713 	assert(sp->encodepfunc != NULL);
714 	assert(sp->encodetile != NULL);
715 
716         /*
717          * Do predictor manipulation in a working buffer to avoid altering
718          * the callers buffer. http://trac.osgeo.org/gdal/ticket/1965
719          */
720         working_copy = (uint8*) _TIFFmalloc(cc0);
721         if( working_copy == NULL )
722         {
723             TIFFErrorExt(tif->tif_clientdata, module,
724                          "Out of memory allocating " TIFF_SSIZE_FORMAT " byte temp buffer.",
725                          cc0 );
726             return 0;
727         }
728         memcpy( working_copy, bp0, cc0 );
729         bp = working_copy;
730 
731 	rowsize = sp->rowsize;
732 	assert(rowsize > 0);
733 	if((cc0%rowsize)!=0)
734     {
735         TIFFErrorExt(tif->tif_clientdata, "PredictorEncodeTile",
736                      "%s", "(cc0%rowsize)!=0");
737         _TIFFfree( working_copy );
738         return 0;
739     }
740 	while (cc > 0) {
741 		(*sp->encodepfunc)(tif, bp, rowsize);
742 		cc -= rowsize;
743 		bp += rowsize;
744 	}
745 	result_code = (*sp->encodetile)(tif, working_copy, cc0, s);
746 
747         _TIFFfree( working_copy );
748 
749         return result_code;
750 }
751 
752 #define	FIELD_PREDICTOR	(FIELD_CODEC+0)		/* XXX */
753 
754 static const TIFFField predictFields[] = {
755     { TIFFTAG_PREDICTOR, 1, 1, TIFF_SHORT, 0, TIFF_SETGET_UINT16, TIFF_SETGET_UINT16, FIELD_PREDICTOR, FALSE, FALSE, "Predictor", NULL },
756 };
757 
758 static int
PredictorVSetField(TIFF * tif,uint32 tag,va_list ap)759 PredictorVSetField(TIFF* tif, uint32 tag, va_list ap)
760 {
761 	TIFFPredictorState *sp = PredictorState(tif);
762 
763 	assert(sp != NULL);
764 	assert(sp->vsetparent != NULL);
765 
766 	switch (tag) {
767 	case TIFFTAG_PREDICTOR:
768 		sp->predictor = (uint16) va_arg(ap, uint16_vap);
769 		TIFFSetFieldBit(tif, FIELD_PREDICTOR);
770 		break;
771 	default:
772 		return (*sp->vsetparent)(tif, tag, ap);
773 	}
774 	tif->tif_flags |= TIFF_DIRTYDIRECT;
775 	return 1;
776 }
777 
778 static int
PredictorVGetField(TIFF * tif,uint32 tag,va_list ap)779 PredictorVGetField(TIFF* tif, uint32 tag, va_list ap)
780 {
781 	TIFFPredictorState *sp = PredictorState(tif);
782 
783 	assert(sp != NULL);
784 	assert(sp->vgetparent != NULL);
785 
786 	switch (tag) {
787 	case TIFFTAG_PREDICTOR:
788 		*va_arg(ap, uint16*) = (uint16)sp->predictor;
789 		break;
790 	default:
791 		return (*sp->vgetparent)(tif, tag, ap);
792 	}
793 	return 1;
794 }
795 
796 static void
PredictorPrintDir(TIFF * tif,FILE * fd,long flags)797 PredictorPrintDir(TIFF* tif, FILE* fd, long flags)
798 {
799 	TIFFPredictorState* sp = PredictorState(tif);
800 
801 	(void) flags;
802 	if (TIFFFieldSet(tif,FIELD_PREDICTOR)) {
803 		fprintf(fd, "  Predictor: ");
804 		switch (sp->predictor) {
805 			case 1: fprintf(fd, "none "); break;
806 			case 2: fprintf(fd, "horizontal differencing "); break;
807 			case 3: fprintf(fd, "floating point predictor "); break;
808 		}
809 		fprintf(fd, "%d (0x%x)\n", sp->predictor, sp->predictor);
810 	}
811 	if (sp->printdir)
812 		(*sp->printdir)(tif, fd, flags);
813 }
814 
815 int
TIFFPredictorInit(TIFF * tif)816 TIFFPredictorInit(TIFF* tif)
817 {
818 	TIFFPredictorState* sp = PredictorState(tif);
819 
820 	assert(sp != 0);
821 
822 	/*
823 	 * Merge codec-specific tag information.
824 	 */
825 	if (!_TIFFMergeFields(tif, predictFields,
826 			      TIFFArrayCount(predictFields))) {
827 		TIFFErrorExt(tif->tif_clientdata, "TIFFPredictorInit",
828 		    "Merging Predictor codec-specific tags failed");
829 		return 0;
830 	}
831 
832 	/*
833 	 * Override parent get/set field methods.
834 	 */
835 	sp->vgetparent = tif->tif_tagmethods.vgetfield;
836 	tif->tif_tagmethods.vgetfield =
837             PredictorVGetField;/* hook for predictor tag */
838 	sp->vsetparent = tif->tif_tagmethods.vsetfield;
839 	tif->tif_tagmethods.vsetfield =
840 	    PredictorVSetField;/* hook for predictor tag */
841 	sp->printdir = tif->tif_tagmethods.printdir;
842 	tif->tif_tagmethods.printdir =
843             PredictorPrintDir;	/* hook for predictor tag */
844 
845 	sp->setupdecode = tif->tif_setupdecode;
846 	tif->tif_setupdecode = PredictorSetupDecode;
847 	sp->setupencode = tif->tif_setupencode;
848 	tif->tif_setupencode = PredictorSetupEncode;
849 
850 	sp->predictor = 1;			/* default value */
851 	sp->encodepfunc = NULL;			/* no predictor routine */
852 	sp->decodepfunc = NULL;			/* no predictor routine */
853 	return 1;
854 }
855 
856 int
TIFFPredictorCleanup(TIFF * tif)857 TIFFPredictorCleanup(TIFF* tif)
858 {
859 	TIFFPredictorState* sp = PredictorState(tif);
860 
861 	assert(sp != 0);
862 
863 	tif->tif_tagmethods.vgetfield = sp->vgetparent;
864 	tif->tif_tagmethods.vsetfield = sp->vsetparent;
865 	tif->tif_tagmethods.printdir = sp->printdir;
866 	tif->tif_setupdecode = sp->setupdecode;
867 	tif->tif_setupencode = sp->setupencode;
868 
869 	return 1;
870 }
871 
872 /* vim: set ts=8 sts=8 sw=8 noet: */
873 /*
874  * Local Variables:
875  * mode: c
876  * c-basic-offset: 8
877  * fill-column: 78
878  * End:
879  */
880