1/* PDFlib GmbH cvsid: $Id: tif_dirread.c 14574 2005-10-29 16:27:43Z bonefish $ */
2
3/*
4 * Copyright (c) 1988-1997 Sam Leffler
5 * Copyright (c) 1991-1997 Silicon Graphics, Inc.
6 *
7 * Permission to use, copy, modify, distribute, and sell this software and
8 * its documentation for any purpose is hereby granted without fee, provided
9 * that (i) the above copyright notices and this permission notice appear in
10 * all copies of the software and related documentation, and (ii) the names of
11 * Sam Leffler and Silicon Graphics may not be used in any advertising or
12 * publicity relating to the software without the specific, prior written
13 * permission of Sam Leffler and Silicon Graphics.
14 *
15 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
17 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
18 *
19 * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
20 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
21 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
22 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
23 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
24 * OF THIS SOFTWARE.
25 */
26
27/*
28 * TIFF Library.
29 *
30 * Directory Read Support Routines.
31 */
32#include "tiffiop.h"
33
34#define	IGNORE	0		/* tag placeholder used below */
35
36#if HAVE_IEEEFP
37#define	TIFFCvtIEEEFloatToNative(tif, n, fp)
38#define	TIFFCvtIEEEDoubleToNative(tif, n, dp)
39#else
40extern	void TIFFCvtIEEEFloatToNative(TIFF*, uint32, float*);
41extern	void TIFFCvtIEEEDoubleToNative(TIFF*, uint32, double*);
42#endif
43
44static	void EstimateStripByteCounts(TIFF*, TIFFDirEntry*, uint16);
45static	void MissingRequired(TIFF*, const char*);
46static	int CheckDirCount(TIFF*, TIFFDirEntry*, uint32);
47static	tsize_t TIFFFetchData(TIFF*, TIFFDirEntry*, char*);
48static	tsize_t TIFFFetchString(TIFF*, TIFFDirEntry*, char*);
49static	float TIFFFetchRational(TIFF*, TIFFDirEntry*);
50static	int TIFFFetchNormalTag(TIFF*, TIFFDirEntry*);
51static	int TIFFFetchPerSampleShorts(TIFF*, TIFFDirEntry*, int*);
52static	int TIFFFetchPerSampleAnys(TIFF*, TIFFDirEntry*, double*);
53static	int TIFFFetchShortArray(TIFF*, TIFFDirEntry*, uint16*);
54static	int TIFFFetchStripThing(TIFF*, TIFFDirEntry*, long, uint32**);
55static	int TIFFFetchExtraSamples(TIFF*, TIFFDirEntry*);
56static	int TIFFFetchRefBlackWhite(TIFF*, TIFFDirEntry*);
57static	float TIFFFetchFloat(TIFF*, TIFFDirEntry*);
58static	int TIFFFetchFloatArray(TIFF*, TIFFDirEntry*, float*);
59static	int TIFFFetchDoubleArray(TIFF*, TIFFDirEntry*, double*);
60static	int TIFFFetchAnyArray(TIFF*, TIFFDirEntry*, double*);
61static	int TIFFFetchShortPair(TIFF*, TIFFDirEntry*);
62static	void ChopUpSingleUncompressedStrip(TIFF*);
63
64static char *
65CheckMalloc(TIFF* tif, tsize_t n, const char* what)
66{
67	char *cp = (char*)_TIFFmalloc(tif, n);
68	if (cp == NULL)
69		TIFFError(tif->tif_name, "No space %s", what);
70	return (cp);
71}
72
73/*
74 * Read the next TIFF directory from a file
75 * and convert it to the internal format.
76 * We read directories sequentially.
77 */
78int
79TIFFReadDirectory(TIFF* tif)
80{
81	register TIFFDirEntry* dp;
82	register int n;
83	register TIFFDirectory* td;
84	TIFFDirEntry* dir;
85	int iv;
86	long v;
87	double dv;
88	const TIFFFieldInfo* fip;
89	int fix;
90	uint16 dircount;
91	toff_t nextdiroff;
92	char* cp;
93	int diroutoforderwarning = 0;
94
95	tif->tif_diroff = tif->tif_nextdiroff;
96	if (tif->tif_diroff == 0)		/* no more directories */
97		return (0);
98	/*
99	 * Cleanup any previous compression state.
100	 */
101	(*tif->tif_cleanup)(tif);
102	tif->tif_curdir++;
103	nextdiroff = 0;
104	if (!isMapped(tif)) {
105		if (!SeekOK(tif, tif->tif_diroff)) {
106			TIFFError(tif->tif_name,
107			    "Seek error accessing TIFF directory");
108			return (0);
109		}
110		if (!ReadOK(tif, &dircount, sizeof (uint16))) {
111			TIFFError(tif->tif_name,
112			    "Can not read TIFF directory count");
113			return (0);
114		}
115
116		/*
117		 * PDFlib GmbH: EFAX (*.jfx) files have a dircount of 0,
118		 * and cannot be processed by TIFFlib.
119		 */
120		if (dircount == 0)
121		    return (0);
122
123		if (tif->tif_flags & TIFF_SWAB)
124			TIFFSwabShort(&dircount);
125		dir = (TIFFDirEntry *)CheckMalloc(tif,
126		    dircount * sizeof (TIFFDirEntry), "to read TIFF directory");
127		if (dir == NULL)
128			return (0);
129		if (!ReadOK(tif, dir, dircount*sizeof (TIFFDirEntry))) {
130			TIFFError(tif->tif_name, "Can not read TIFF directory");
131			goto bad;
132		}
133		/*
134		 * Read offset to next directory for sequential scans.
135		 */
136                (void) ReadOK(tif, &nextdiroff, ((tsize_t) sizeof (uint32)));
137	} else {
138		toff_t off = tif->tif_diroff;
139
140		if (off + sizeof (uint16) > tif->tif_size) {
141			TIFFError(tif->tif_name,
142			    "Can not read TIFF directory count");
143			return (0);
144		} else
145		    _TIFFmemcpy(&dircount, tif->tif_base + off, sizeof(uint16));
146		off += sizeof (uint16);
147		if (tif->tif_flags & TIFF_SWAB)
148			TIFFSwabShort(&dircount);
149		dir = (TIFFDirEntry *)CheckMalloc(tif,
150		    dircount * sizeof (TIFFDirEntry), "to read TIFF directory");
151		if (dir == NULL)
152			return (0);
153		if (off + dircount*sizeof (TIFFDirEntry) > tif->tif_size) {
154			TIFFError(tif->tif_name, "Can not read TIFF directory");
155			goto bad;
156		} else
157			_TIFFmemcpy(dir, tif->tif_base + off,
158			    dircount*sizeof (TIFFDirEntry));
159		off += dircount* sizeof (TIFFDirEntry);
160		if (off + sizeof (uint32) <= tif->tif_size)
161		    _TIFFmemcpy(&nextdiroff, tif->tif_base+off, sizeof(uint32));
162	}
163	if (tif->tif_flags & TIFF_SWAB)
164		TIFFSwabLong(&nextdiroff);
165	tif->tif_nextdiroff = nextdiroff;
166
167	tif->tif_flags &= ~TIFF_BEENWRITING;	/* reset before new dir */
168	/*
169	 * Setup default value and then make a pass over
170	 * the fields to check type and tag information,
171	 * and to extract info required to size data
172	 * structures.  A second pass is made afterwards
173	 * to read in everthing not taken in the first pass.
174	 */
175	td = &tif->tif_dir;
176	/* free any old stuff and reinit */
177	TIFFFreeDirectory(tif);
178	TIFFDefaultDirectory(tif);
179	/*
180	 * Electronic Arts writes gray-scale TIFF files
181	 * without a PlanarConfiguration directory entry.
182	 * Thus we setup a default value here, even though
183	 * the TIFF spec says there is no default value.
184	 */
185	TIFFSetField(tif, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG);
186
187	/*
188	 * Sigh, we must make a separate pass through the
189	 * directory for the following reason:
190	 *
191	 * We must process the Compression tag in the first pass
192	 * in order to merge in codec-private tag definitions (otherwise
193	 * we may get complaints about unknown tags).  However, the
194	 * Compression tag may be dependent on the SamplesPerPixel
195	 * tag value because older TIFF specs permited Compression
196	 * to be written as a SamplesPerPixel-count tag entry.
197	 * Thus if we don't first figure out the correct SamplesPerPixel
198	 * tag value then we may end up ignoring the Compression tag
199	 * value because it has an incorrect count value (if the
200	 * true value of SamplesPerPixel is not 1).
201	 *
202	 * It sure would have been nice if Aldus had really thought
203	 * this stuff through carefully.
204	 */
205	for (dp = dir, n = dircount; n > 0; n--, dp++) {
206		if (tif->tif_flags & TIFF_SWAB) {
207			TIFFSwabArrayOfShort(&dp->tdir_tag, 2);
208			TIFFSwabArrayOfLong(&dp->tdir_count, 2);
209		}
210		if (dp->tdir_tag == TIFFTAG_SAMPLESPERPIXEL) {
211			if (!TIFFFetchNormalTag(tif, dp))
212				goto bad;
213			dp->tdir_tag = IGNORE;
214		}
215	}
216	/*
217	 * First real pass over the directory.
218	 */
219	fix = 0;
220	for (dp = dir, n = dircount; n > 0; n--, dp++) {
221
222                /*
223                 * Find the field information entry for this tag.
224		 * Added check for tags to ignore ... [BFC]
225                 */
226		if( TIFFReassignTagToIgnore(TIS_EXTRACT, dp->tdir_tag) )
227                    dp->tdir_tag = IGNORE;
228
229		if (dp->tdir_tag == IGNORE)
230                    continue;
231
232		/*
233		 * Silicon Beach (at least) writes unordered
234		 * directory tags (violating the spec).  Handle
235		 * it here, but be obnoxious (maybe they'll fix it?).
236		 */
237		if (dp->tdir_tag < tif->tif_fieldinfo[fix]->field_tag) {
238			if (!diroutoforderwarning) {
239				TIFFWarning(tif->tif_name,
240	"invalid TIFF directory; tags are not sorted in ascending order");
241				diroutoforderwarning = 1;
242			}
243			fix = 0;			/* O(n^2) */
244		}
245		while (fix < tif->tif_nfields &&
246		    tif->tif_fieldinfo[fix]->field_tag < dp->tdir_tag)
247			fix++;
248		if (fix == tif->tif_nfields ||
249		    tif->tif_fieldinfo[fix]->field_tag != dp->tdir_tag) {
250			TIFFWarning(tif->tif_name,
251			    "unknown field with tag %d (0x%x) ignored",
252			    dp->tdir_tag,  dp->tdir_tag);
253			dp->tdir_tag = IGNORE;
254			fix = 0;			/* restart search */
255			continue;
256		}
257		/*
258		 * Null out old tags that we ignore.
259		 */
260		if (tif->tif_fieldinfo[fix]->field_bit == FIELD_IGNORE) {
261	ignore:
262			dp->tdir_tag = IGNORE;
263			continue;
264		}
265		/*
266		 * Check data type.
267		 */
268		fip = tif->tif_fieldinfo[fix];
269		while (dp->tdir_type != (tif_short) fip->field_type) {
270			if (fip->field_type == TIFF_ANY)	/* wildcard */
271				break;
272			fip++, fix++;
273			if (fix == tif->tif_nfields ||
274			    fip->field_tag != dp->tdir_tag) {
275				TIFFWarning(tif->tif_name,
276				   "wrong data type %d for \"%s\"; tag ignored",
277				    dp->tdir_type, fip[-1].field_name);
278				goto ignore;
279			}
280		}
281		/*
282		 * Check count if known in advance.
283		 */
284		if (fip->field_readcount != TIFF_VARIABLE) {
285			uint32 expected = (fip->field_readcount == TIFF_SPP) ?
286			    (uint32) td->td_samplesperpixel :
287			    (uint32) fip->field_readcount;
288			if (!CheckDirCount(tif, dp, expected))
289				goto ignore;
290		}
291
292		switch (dp->tdir_tag) {
293		case TIFFTAG_COMPRESSION:
294			/*
295			 * The 5.0 spec says the Compression tag has
296			 * one value, while earlier specs say it has
297			 * one value per sample.  Because of this, we
298			 * accept the tag if one value is supplied.
299			 */
300			if (dp->tdir_count == 1) {
301				v = TIFFExtractData(tif,
302				    dp->tdir_type, dp->tdir_offset);
303				if (!TIFFSetField(tif, dp->tdir_tag, (int)v))
304					goto bad;
305				break;
306			}
307			if (!TIFFFetchPerSampleShorts(tif, dp, &iv) ||
308			    !TIFFSetField(tif, dp->tdir_tag, iv))
309				goto bad;
310			dp->tdir_tag = IGNORE;
311			break;
312		case TIFFTAG_STRIPOFFSETS:
313		case TIFFTAG_STRIPBYTECOUNTS:
314		case TIFFTAG_TILEOFFSETS:
315		case TIFFTAG_TILEBYTECOUNTS:
316			TIFFSetFieldBit(tif, fip->field_bit);
317			break;
318		case TIFFTAG_IMAGEWIDTH:
319		case TIFFTAG_IMAGELENGTH:
320		case TIFFTAG_IMAGEDEPTH:
321		case TIFFTAG_TILELENGTH:
322		case TIFFTAG_TILEWIDTH:
323		case TIFFTAG_TILEDEPTH:
324		case TIFFTAG_PLANARCONFIG:
325		case TIFFTAG_ROWSPERSTRIP:
326			if (!TIFFFetchNormalTag(tif, dp))
327				goto bad;
328			dp->tdir_tag = IGNORE;
329			break;
330		case TIFFTAG_EXTRASAMPLES:
331			(void) TIFFFetchExtraSamples(tif, dp);
332			dp->tdir_tag = IGNORE;
333			break;
334		}
335	}
336
337	/*
338	 * Allocate directory structure and setup defaults.
339	 */
340	if (!TIFFFieldSet(tif, FIELD_IMAGEDIMENSIONS)) {
341		MissingRequired(tif, "ImageLength");
342		goto bad;
343	}
344	if (!TIFFFieldSet(tif, FIELD_PLANARCONFIG)) {
345		MissingRequired(tif, "PlanarConfiguration");
346		goto bad;
347	}
348	/*
349 	 * Setup appropriate structures (by strip or by tile)
350	 */
351	if (!TIFFFieldSet(tif, FIELD_TILEDIMENSIONS)) {
352		td->td_nstrips = TIFFNumberOfStrips(tif);
353		td->td_tilewidth = td->td_imagewidth;
354		td->td_tilelength = td->td_rowsperstrip;
355		td->td_tiledepth = td->td_imagedepth;
356		tif->tif_flags &= ~TIFF_ISTILED;
357	} else {
358		td->td_nstrips = TIFFNumberOfTiles(tif);
359		tif->tif_flags |= TIFF_ISTILED;
360	}
361	td->td_stripsperimage = td->td_nstrips;
362	if (td->td_planarconfig == PLANARCONFIG_SEPARATE)
363		td->td_stripsperimage /= td->td_samplesperpixel;
364	if (!TIFFFieldSet(tif, FIELD_STRIPOFFSETS)) {
365		MissingRequired(tif,
366		    isTiled(tif) ? "TileOffsets" : "StripOffsets");
367		goto bad;
368	}
369
370	/*
371	 * Second pass: extract other information.
372	 */
373	for (dp = dir, n = dircount; n > 0; n--, dp++) {
374		if (dp->tdir_tag == IGNORE)
375			continue;
376		switch (dp->tdir_tag) {
377		case TIFFTAG_MINSAMPLEVALUE:
378		case TIFFTAG_MAXSAMPLEVALUE:
379		case TIFFTAG_BITSPERSAMPLE:
380			/*
381			 * The 5.0 spec says the Compression tag has
382			 * one value, while earlier specs say it has
383			 * one value per sample.  Because of this, we
384			 * accept the tag if one value is supplied.
385			 *
386			 * The MinSampleValue, MaxSampleValue and
387			 * BitsPerSample tags are supposed to be written
388			 * as one value/sample, but some vendors incorrectly
389			 * write one value only -- so we accept that
390			 * as well (yech).
391			 */
392			if (dp->tdir_count == 1) {
393				v = TIFFExtractData(tif,
394				    dp->tdir_type, dp->tdir_offset);
395				if (!TIFFSetField(tif, dp->tdir_tag, (int)v))
396					goto bad;
397				break;
398			}
399			/* fall thru... */
400		case TIFFTAG_DATATYPE:
401		case TIFFTAG_SAMPLEFORMAT:
402			if (!TIFFFetchPerSampleShorts(tif, dp, &iv) ||
403			    !TIFFSetField(tif, dp->tdir_tag, iv))
404				goto bad;
405			break;
406		case TIFFTAG_SMINSAMPLEVALUE:
407		case TIFFTAG_SMAXSAMPLEVALUE:
408			if (!TIFFFetchPerSampleAnys(tif, dp, &dv) ||
409			    !TIFFSetField(tif, dp->tdir_tag, dv))
410				goto bad;
411			break;
412		case TIFFTAG_STRIPOFFSETS:
413		case TIFFTAG_TILEOFFSETS:
414			if (!TIFFFetchStripThing(tif, dp,
415			    td->td_nstrips, &td->td_stripoffset))
416				goto bad;
417			break;
418		case TIFFTAG_STRIPBYTECOUNTS:
419		case TIFFTAG_TILEBYTECOUNTS:
420			if (!TIFFFetchStripThing(tif, dp,
421			    td->td_nstrips, &td->td_stripbytecount))
422				goto bad;
423			break;
424		case TIFFTAG_COLORMAP:
425		case TIFFTAG_TRANSFERFUNCTION:
426			/*
427			 * TransferFunction can have either 1x or 3x data
428			 * values; Colormap can have only 3x items.
429			 */
430			v = 1L<<td->td_bitspersample;
431			if (dp->tdir_tag == TIFFTAG_COLORMAP ||
432			    dp->tdir_count != (uint32) v) {
433				if (!CheckDirCount(tif, dp, (uint32)(3*v)))
434					break;
435			}
436			v *= sizeof (uint16);
437			cp = CheckMalloc(tif, dp->tdir_count * sizeof (uint16),
438			    "to read \"TransferFunction\" tag");
439			if (cp != NULL) {
440				if (TIFFFetchData(tif, dp, cp)) {
441					/*
442					 * This deals with there being only
443					 * one array to apply to all samples.
444					 */
445					uint32 c =
446					    (uint32)1 << td->td_bitspersample;
447					if (dp->tdir_count == c)
448						v = 0;
449					TIFFSetField(tif, dp->tdir_tag,
450					    cp, cp+v, cp+2*v);
451				}
452				_TIFFfree(tif, cp);
453			}
454			break;
455		case TIFFTAG_PAGENUMBER:
456		case TIFFTAG_HALFTONEHINTS:
457		case TIFFTAG_YCBCRSUBSAMPLING:
458		case TIFFTAG_DOTRANGE:
459			(void) TIFFFetchShortPair(tif, dp);
460			break;
461#ifdef COLORIMETRY_SUPPORT
462		case TIFFTAG_REFERENCEBLACKWHITE:
463			(void) TIFFFetchRefBlackWhite(tif, dp);
464			break;
465#endif
466/* BEGIN REV 4.0 COMPATIBILITY */
467		case TIFFTAG_OSUBFILETYPE:
468			v = 0;
469			switch (TIFFExtractData(tif, dp->tdir_type,
470			    dp->tdir_offset)) {
471			case OFILETYPE_REDUCEDIMAGE:
472				v = FILETYPE_REDUCEDIMAGE;
473				break;
474			case OFILETYPE_PAGE:
475				v = FILETYPE_PAGE;
476				break;
477			}
478			if (v)
479				(void) TIFFSetField(tif,
480				    TIFFTAG_SUBFILETYPE, (int)v);
481			break;
482/* END REV 4.0 COMPATIBILITY */
483		default:
484			(void) TIFFFetchNormalTag(tif, dp);
485			break;
486		}
487	}
488	/*
489	 * Verify Palette image has a Colormap.
490	 */
491	if (td->td_photometric == PHOTOMETRIC_PALETTE &&
492	    !TIFFFieldSet(tif, FIELD_COLORMAP)) {
493		MissingRequired(tif, "Colormap");
494		goto bad;
495	}
496	/*
497	 * Attempt to deal with a missing StripByteCounts tag.
498	 */
499	if (!TIFFFieldSet(tif, FIELD_STRIPBYTECOUNTS)) {
500		/*
501		 * Some manufacturers violate the spec by not giving
502		 * the size of the strips.  In this case, assume there
503		 * is one uncompressed strip of data.
504		 */
505		if ((td->td_planarconfig == PLANARCONFIG_CONTIG &&
506		    td->td_nstrips > 1) ||
507		    (td->td_planarconfig == PLANARCONFIG_SEPARATE &&
508		     td->td_nstrips != td->td_samplesperpixel)) {
509		    MissingRequired(tif, "StripByteCounts");
510		    goto bad;
511		}
512		TIFFWarning(tif->tif_name,
513"TIFF directory is missing required \"%s\" field, calculating from imagelength",
514		    _TIFFFieldWithTag(tif,TIFFTAG_STRIPBYTECOUNTS)->field_name);
515		EstimateStripByteCounts(tif, dir, dircount);
516#define	BYTECOUNTLOOKSBAD \
517    ((td->td_stripbytecount[0] == 0 && td->td_stripoffset[0] != 0) || \
518    (td->td_compression == COMPRESSION_NONE && \
519     td->td_stripbytecount[0] > TIFFGetFileSize(tif) - td->td_stripoffset[0]))
520	} else if (td->td_nstrips == 1 && BYTECOUNTLOOKSBAD) {
521		/*
522		 * Plexus (and others) sometimes give a value
523		 * of zero for a tag when they don't know what
524		 * the correct value is!  Try and handle the
525		 * simple case of estimating the size of a one
526		 * strip image.
527		 */
528		TIFFWarning(tif->tif_name,
529	    "Bogus \"%s\" field, ignoring and calculating from imagelength",
530		    _TIFFFieldWithTag(tif,TIFFTAG_STRIPBYTECOUNTS)->field_name);
531		EstimateStripByteCounts(tif, dir, dircount);
532	}
533	if (dir)
534		_TIFFfree(tif, (char *)dir);
535	if (!TIFFFieldSet(tif, FIELD_MAXSAMPLEVALUE))
536		td->td_maxsamplevalue = (uint16)((1L<<td->td_bitspersample)-1);
537	/*
538	 * Setup default compression scheme.
539	 */
540	if (!TIFFFieldSet(tif, FIELD_COMPRESSION))
541		TIFFSetField(tif, TIFFTAG_COMPRESSION, COMPRESSION_NONE);
542        /*
543         * Some manufacturers make life difficult by writing
544	 * large amounts of uncompressed data as a single strip.
545	 * This is contrary to the recommendations of the spec.
546         * The following makes an attempt at breaking such images
547	 * into strips closer to the recommended 8k bytes.  A
548	 * side effect, however, is that the RowsPerStrip tag
549	 * value may be changed.
550         */
551	if (td->td_nstrips == 1 && td->td_compression == COMPRESSION_NONE &&
552	    (tif->tif_flags & (TIFF_STRIPCHOP|TIFF_ISTILED)) == TIFF_STRIPCHOP)
553		ChopUpSingleUncompressedStrip(tif);
554	/*
555	 * Reinitialize i/o since we are starting on a new directory.
556	 */
557	tif->tif_row = (uint32) -1;
558	tif->tif_curstrip = (tstrip_t) -1;
559	tif->tif_col = (uint32) -1;
560	tif->tif_curtile = (ttile_t) -1;
561	tif->tif_tilesize = TIFFTileSize(tif);
562	tif->tif_scanlinesize = TIFFScanlineSize(tif);
563	return (1);
564bad:
565	if (dir)
566		_TIFFfree(tif, dir);
567	return (0);
568}
569
570static void
571EstimateStripByteCounts(TIFF* tif, TIFFDirEntry* dir, uint16 dircount)
572{
573	register TIFFDirEntry *dp;
574	register TIFFDirectory *td = &tif->tif_dir;
575	uint16 i;
576
577	if (td->td_stripbytecount)
578		_TIFFfree(tif, td->td_stripbytecount);
579	td->td_stripbytecount = (uint32*)
580	    CheckMalloc(tif, td->td_nstrips * sizeof (uint32),
581		"for \"StripByteCounts\" array");
582	if (td->td_compression != COMPRESSION_NONE) {
583		uint32 space = (uint32)(sizeof (TIFFHeader)
584		    + sizeof (uint16)
585		    + (dircount * sizeof (TIFFDirEntry))
586		    + sizeof (uint32));
587		toff_t filesize = TIFFGetFileSize(tif);
588		uint16 n;
589
590		/* calculate amount of space used by indirect values */
591		for (dp = dir, n = dircount; n > 0; n--, dp++) {
592			uint32 cc = dp->tdir_count*tiffDataWidth[dp->tdir_type];
593			if (cc > sizeof (uint32))
594				space += cc;
595		}
596		space = filesize - space;
597		if (td->td_planarconfig == PLANARCONFIG_SEPARATE)
598			space /= td->td_samplesperpixel;
599		for (i = 0; i < td->td_nstrips; i++)
600			td->td_stripbytecount[i] = space;
601		/*
602		 * This gross hack handles the case were the offset to
603		 * the last strip is past the place where we think the strip
604		 * should begin.  Since a strip of data must be contiguous,
605		 * it's safe to assume that we've overestimated the amount
606		 * of data in the strip and trim this number back accordingly.
607		 */
608		i--;
609		if (((toff_t)(td->td_stripoffset[i]+td->td_stripbytecount[i]))
610                                                               > filesize)
611			td->td_stripbytecount[i] =
612			    filesize - td->td_stripoffset[i];
613	} else {
614		uint32 rowbytes = TIFFScanlineSize(tif);
615		uint32 rowsperstrip = td->td_imagelength/td->td_stripsperimage;
616		for (i = 0; i < td->td_nstrips; i++)
617			td->td_stripbytecount[i] = rowbytes*rowsperstrip;
618	}
619	TIFFSetFieldBit(tif, FIELD_STRIPBYTECOUNTS);
620	if (!TIFFFieldSet(tif, FIELD_ROWSPERSTRIP))
621		td->td_rowsperstrip = td->td_imagelength;
622}
623
624static void
625MissingRequired(TIFF* tif, const char* tagname)
626{
627	TIFFError(tif->tif_name,
628	    "TIFF directory is missing required \"%s\" field", tagname);
629}
630
631/*
632 * Check the count field of a directory
633 * entry against a known value.  The caller
634 * is expected to skip/ignore the tag if
635 * there is a mismatch.
636 */
637static int
638CheckDirCount(TIFF* tif, TIFFDirEntry* dir, uint32 count)
639{
640	if (count != dir->tdir_count) {
641		TIFFWarning(tif->tif_name,
642	"incorrect count for field \"%s\" (%lu, expecting %lu); tag ignored",
643		    _TIFFFieldWithTag(tif, dir->tdir_tag)->field_name,
644		    dir->tdir_count, count);
645		return (0);
646	}
647	return (1);
648}
649
650/*
651 * Fetch a contiguous directory item.
652 */
653static tsize_t
654TIFFFetchData(TIFF* tif, TIFFDirEntry* dir, char* cp)
655{
656	int w = tiffDataWidth[dir->tdir_type];
657	tsize_t cc = dir->tdir_count * w;
658
659	if (!isMapped(tif)) {
660		if (!SeekOK(tif, dir->tdir_offset))
661			goto bad;
662		if (!ReadOK(tif, cp, cc))
663			goto bad;
664	} else {
665		if (dir->tdir_offset + cc > tif->tif_size)
666			goto bad;
667		_TIFFmemcpy(cp, tif->tif_base + dir->tdir_offset, cc);
668	}
669	if (tif->tif_flags & TIFF_SWAB) {
670		switch (dir->tdir_type) {
671		case TIFF_SHORT:
672		case TIFF_SSHORT:
673			TIFFSwabArrayOfShort((uint16*) cp, dir->tdir_count);
674			break;
675		case TIFF_LONG:
676		case TIFF_SLONG:
677		case TIFF_FLOAT:
678			TIFFSwabArrayOfLong((uint32*) cp, dir->tdir_count);
679			break;
680		case TIFF_RATIONAL:
681		case TIFF_SRATIONAL:
682			TIFFSwabArrayOfLong((uint32*) cp, 2*dir->tdir_count);
683			break;
684		case TIFF_DOUBLE:
685			TIFFSwabArrayOfDouble((double*) cp, dir->tdir_count);
686			break;
687		}
688	}
689	return (cc);
690bad:
691	TIFFError(tif->tif_name, "Error fetching data for field \"%s\"",
692	    _TIFFFieldWithTag(tif, dir->tdir_tag)->field_name);
693	return ((tsize_t) 0);
694}
695
696/*
697 * Fetch an ASCII item from the file.
698 */
699static tsize_t
700TIFFFetchString(TIFF* tif, TIFFDirEntry* dir, char* cp)
701{
702	if (dir->tdir_count <= 4) {
703		uint32 l = dir->tdir_offset;
704		if (tif->tif_flags & TIFF_SWAB)
705			TIFFSwabLong(&l);
706		_TIFFmemcpy(cp, &l, dir->tdir_count);
707		return (1);
708	}
709	return (TIFFFetchData(tif, dir, cp));
710}
711
712/*
713 * Convert numerator+denominator to float.
714 */
715static int
716cvtRational(TIFF* tif, TIFFDirEntry* dir, uint32 num, uint32 denom, float* rv)
717{
718	if (denom == 0) {
719		TIFFError(tif->tif_name,
720		    "%s: Rational with zero denominator (num = %lu)",
721		    _TIFFFieldWithTag(tif, dir->tdir_tag)->field_name, num);
722		return (0);
723	} else {
724		if (dir->tdir_type == TIFF_RATIONAL)
725			*rv = ((float)num / (float)denom);
726		else
727			*rv = ((float)(int32)num / (float)(int32)denom);
728		return (1);
729	}
730}
731
732/*
733 * Fetch a rational item from the file
734 * at offset off and return the value
735 * as a floating point number.
736 */
737static float
738TIFFFetchRational(TIFF* tif, TIFFDirEntry* dir)
739{
740	uint32 l[2];
741	float v;
742
743	return (!TIFFFetchData(tif, dir, (char *)l) ||
744	    !cvtRational(tif, dir, l[0], l[1], &v) ? 1.0f : v);
745}
746
747/*
748 * Fetch a single floating point value
749 * from the offset field and return it
750 * as a native float.
751 */
752static float
753TIFFFetchFloat(TIFF* tif, TIFFDirEntry* dir)
754{
755	long l = TIFFExtractData(tif, dir->tdir_type, dir->tdir_offset);
756	float v = *(float*) &l;
757	TIFFCvtIEEEFloatToNative(tif, 1, &v);
758	return (v);
759}
760
761/*
762 * Fetch an array of BYTE or SBYTE values.
763 */
764static int
765TIFFFetchByteArray(TIFF* tif, TIFFDirEntry* dir, uint16* v)
766{
767    if (dir->tdir_count <= 4) {
768        /*
769         * Extract data from offset field.
770         */
771        if (tif->tif_header.tiff_magic == TIFF_BIGENDIAN) {
772            switch (dir->tdir_count) {
773                case 4: v[3] = (uint16)(dir->tdir_offset & 0xff);
774                case 3: v[2] = (uint16)((dir->tdir_offset >> 8) & 0xff);
775                case 2: v[1] = (uint16)((dir->tdir_offset >> 16) & 0xff);
776                case 1: v[0] = (uint16)(dir->tdir_offset >> 24);
777            }
778        } else {
779            switch (dir->tdir_count) {
780                case 4: v[3] = (uint16)(dir->tdir_offset >> 24);
781                case 3: v[2] = (uint16)((dir->tdir_offset >> 16) & 0xff);
782                case 2: v[1] = (uint16)((dir->tdir_offset >> 8) & 0xff);
783                case 1: v[0] = (uint16)(dir->tdir_offset & 0xff);
784            }
785        }
786        return (1);
787    } else
788        return (TIFFFetchData(tif, dir, (char*) v) != 0);	/* XXX */
789}
790
791/*
792 * Fetch an array of SHORT or SSHORT values.
793 */
794static int
795TIFFFetchShortArray(TIFF* tif, TIFFDirEntry* dir, uint16* v)
796{
797	if (dir->tdir_count <= 2) {
798		if (tif->tif_header.tiff_magic == TIFF_BIGENDIAN) {
799			switch (dir->tdir_count) {
800			case 2: v[1] = (uint16) (dir->tdir_offset & 0xffff);
801			case 1: v[0] = (uint16) (dir->tdir_offset >> 16);
802			}
803		} else {
804			switch (dir->tdir_count) {
805			case 2: v[1] = (uint16) (dir->tdir_offset >> 16);
806			case 1: v[0] = (uint16) (dir->tdir_offset & 0xffff);
807			}
808		}
809		return (1);
810	} else
811		return (TIFFFetchData(tif, dir, (char *)v) != 0);
812}
813
814/*
815 * Fetch a pair of SHORT or BYTE values.
816 */
817static int
818TIFFFetchShortPair(TIFF* tif, TIFFDirEntry* dir)
819{
820	uint16 v[2];
821	int ok = 0;
822
823	switch (dir->tdir_type) {
824	case TIFF_SHORT:
825	case TIFF_SSHORT:
826		ok = TIFFFetchShortArray(tif, dir, v);
827		break;
828	case TIFF_BYTE:
829	case TIFF_SBYTE:
830		ok  = TIFFFetchByteArray(tif, dir, v);
831		break;
832	}
833	if (ok)
834		TIFFSetField(tif, dir->tdir_tag, v[0], v[1]);
835	return (ok);
836}
837
838/*
839 * Fetch an array of LONG or SLONG values.
840 */
841static int
842TIFFFetchLongArray(TIFF* tif, TIFFDirEntry* dir, uint32* v)
843{
844	if (dir->tdir_count == 1) {
845		v[0] = dir->tdir_offset;
846		return (1);
847	} else
848		return (TIFFFetchData(tif, dir, (char*) v) != 0);
849}
850
851/*
852 * Fetch an array of RATIONAL or SRATIONAL values.
853 */
854static int
855TIFFFetchRationalArray(TIFF* tif, TIFFDirEntry* dir, float* v)
856{
857	int ok = 0;
858	uint32* l;
859
860	l = (uint32*)CheckMalloc(tif,
861	    dir->tdir_count*tiffDataWidth[dir->tdir_type],
862	    "to fetch array of rationals");
863	if (l) {
864		if (TIFFFetchData(tif, dir, (char *)l)) {
865			uint32 i;
866			for (i = 0; i < dir->tdir_count; i++) {
867				ok = cvtRational(tif, dir,
868				    l[2*i+0], l[2*i+1], &v[i]);
869				if (!ok)
870					break;
871			}
872		}
873		_TIFFfree(tif, (char *)l);
874	}
875	return (ok);
876}
877
878/*
879 * Fetch an array of FLOAT values.
880 */
881static int
882TIFFFetchFloatArray(TIFF* tif, TIFFDirEntry* dir, float* v)
883{
884
885	if (dir->tdir_count == 1) {
886		v[0] = *(float*) &dir->tdir_offset;
887		TIFFCvtIEEEFloatToNative(tif, dir->tdir_count, v);
888		return (1);
889	} else	if (TIFFFetchData(tif, dir, (char*) v)) {
890		TIFFCvtIEEEFloatToNative(tif, dir->tdir_count, v);
891		return (1);
892	} else
893		return (0);
894}
895
896/*
897 * Fetch an array of DOUBLE values.
898 */
899static int
900TIFFFetchDoubleArray(TIFF* tif, TIFFDirEntry* dir, double* v)
901{
902	if (TIFFFetchData(tif, dir, (char*) v)) {
903		TIFFCvtIEEEDoubleToNative(tif, dir->tdir_count, v);
904		return (1);
905	} else
906		return (0);
907}
908
909/*
910 * Fetch an array of ANY values.  The actual values are
911 * returned as doubles which should be able hold all the
912 * types.  Yes, there really should be an tany_t to avoid
913 * this potential non-portability ...  Note in particular
914 * that we assume that the double return value vector is
915 * large enough to read in any fundamental type.  We use
916 * that vector as a buffer to read in the base type vector
917 * and then convert it in place to double (from end
918 * to front of course).
919 */
920static int
921TIFFFetchAnyArray(TIFF* tif, TIFFDirEntry* dir, double* v)
922{
923	int i;
924
925	switch (dir->tdir_type) {
926	case TIFF_BYTE:
927	case TIFF_SBYTE:
928		if (!TIFFFetchByteArray(tif, dir, (uint16*) v))
929			return (0);
930		if (dir->tdir_type == TIFF_BYTE) {
931			uint16* vp = (uint16*) v;
932			for (i = dir->tdir_count-1; i >= 0; i--)
933				v[i] = vp[i];
934		} else {
935			int16* vp = (int16*) v;
936			for (i = dir->tdir_count-1; i >= 0; i--)
937				v[i] = vp[i];
938		}
939		break;
940	case TIFF_SHORT:
941	case TIFF_SSHORT:
942		if (!TIFFFetchShortArray(tif, dir, (uint16*) v))
943			return (0);
944		if (dir->tdir_type == TIFF_SHORT) {
945			uint16* vp = (uint16*) v;
946			for (i = dir->tdir_count-1; i >= 0; i--)
947				v[i] = vp[i];
948		} else {
949			int16* vp = (int16*) v;
950			for (i = dir->tdir_count-1; i >= 0; i--)
951				v[i] = vp[i];
952		}
953		break;
954	case TIFF_LONG:
955	case TIFF_SLONG:
956		if (!TIFFFetchLongArray(tif, dir, (uint32*) v))
957			return (0);
958		if (dir->tdir_type == TIFF_LONG) {
959			uint32* vp = (uint32*) v;
960			for (i = dir->tdir_count-1; i >= 0; i--)
961				v[i] = vp[i];
962		} else {
963			int32* vp = (int32*) v;
964			for (i = dir->tdir_count-1; i >= 0; i--)
965				v[i] = vp[i];
966		}
967		break;
968	case TIFF_RATIONAL:
969	case TIFF_SRATIONAL:
970		if (!TIFFFetchRationalArray(tif, dir, (float*) v))
971			return (0);
972		{ float* vp = (float*) v;
973		  for (i = dir->tdir_count-1; i >= 0; i--)
974			v[i] = vp[i];
975		}
976		break;
977	case TIFF_FLOAT:
978		if (!TIFFFetchFloatArray(tif, dir, (float*) v))
979			return (0);
980		{ float* vp = (float*) v;
981		  for (i = dir->tdir_count-1; i >= 0; i--)
982			v[i] = vp[i];
983		}
984		break;
985	case TIFF_DOUBLE:
986		return (TIFFFetchDoubleArray(tif, dir, (double*) v));
987	default:
988		/* TIFF_NOTYPE */
989		/* TIFF_ASCII */
990		/* TIFF_UNDEFINED */
991		TIFFError(tif->tif_name,
992		    "Cannot read TIFF_ANY type %d for field \"%s\"",
993		    _TIFFFieldWithTag(tif, dir->tdir_tag)->field_name);
994		return (0);
995	}
996	return (1);
997}
998
999/*
1000 * Fetch a tag that is not handled by special case code.
1001 */
1002static int
1003TIFFFetchNormalTag(TIFF* tif, TIFFDirEntry* dp)
1004{
1005	static const char mesg[] = "to fetch tag value";
1006	int ok = 0;
1007	const TIFFFieldInfo* fip = _TIFFFieldWithTag(tif, dp->tdir_tag);
1008
1009	if (dp->tdir_count > 1) {		/* array of values */
1010		char* cp = NULL;
1011
1012		switch (dp->tdir_type) {
1013		case TIFF_BYTE:
1014		case TIFF_SBYTE:
1015			/* NB: always expand BYTE values to shorts */
1016			cp = CheckMalloc(tif,
1017			    dp->tdir_count * sizeof (uint16), mesg);
1018			ok = cp && TIFFFetchByteArray(tif, dp, (uint16*) cp);
1019			break;
1020		case TIFF_SHORT:
1021		case TIFF_SSHORT:
1022			cp = CheckMalloc(tif,
1023			    dp->tdir_count * sizeof (uint16), mesg);
1024			ok = cp && TIFFFetchShortArray(tif, dp, (uint16*) cp);
1025			break;
1026		case TIFF_LONG:
1027		case TIFF_SLONG:
1028			cp = CheckMalloc(tif,
1029			    dp->tdir_count * sizeof (uint32), mesg);
1030			ok = cp && TIFFFetchLongArray(tif, dp, (uint32*) cp);
1031			break;
1032		case TIFF_RATIONAL:
1033		case TIFF_SRATIONAL:
1034			cp = CheckMalloc(tif,
1035			    dp->tdir_count * sizeof (float), mesg);
1036			ok = cp && TIFFFetchRationalArray(tif, dp, (float*) cp);
1037			break;
1038		case TIFF_FLOAT:
1039			cp = CheckMalloc(tif,
1040			    dp->tdir_count * sizeof (float), mesg);
1041			ok = cp && TIFFFetchFloatArray(tif, dp, (float*) cp);
1042			break;
1043		case TIFF_DOUBLE:
1044			cp = CheckMalloc(tif,
1045			    dp->tdir_count * sizeof (double), mesg);
1046			ok = cp && TIFFFetchDoubleArray(tif, dp, (double*) cp);
1047			break;
1048		case TIFF_ASCII:
1049		case TIFF_UNDEFINED:		/* bit of a cheat... */
1050			/*
1051			 * Some vendors write strings w/o the trailing
1052			 * NULL byte, so always append one just in case.
1053			 */
1054			cp = CheckMalloc(tif, dp->tdir_count+1, mesg);
1055			if( (ok = (cp && TIFFFetchString(tif, dp, cp))) != 0 )
1056				cp[dp->tdir_count] = '\0';	/* XXX */
1057			break;
1058		}
1059		if (ok) {
1060			ok = (fip->field_passcount ?
1061			    TIFFSetField(tif, dp->tdir_tag, dp->tdir_count, cp)
1062			  : TIFFSetField(tif, dp->tdir_tag, cp));
1063		}
1064		if (cp != NULL)
1065			_TIFFfree(tif, cp);
1066	} else if (CheckDirCount(tif, dp, 1)) {	/* singleton value */
1067		switch (dp->tdir_type) {
1068		case TIFF_BYTE:
1069		case TIFF_SBYTE:
1070		case TIFF_SHORT:
1071		case TIFF_SSHORT:
1072			/*
1073			 * If the tag is also acceptable as a LONG or SLONG
1074			 * then TIFFSetField will expect an uint32 parameter
1075			 * passed to it (through varargs).  Thus, for machines
1076			 * where sizeof (int) != sizeof (uint32) we must do
1077			 * a careful check here.  It's hard to say if this
1078			 * is worth optimizing.
1079			 *
1080			 * NB: We use TIFFFieldWithTag here knowing that
1081			 *     it returns us the first entry in the table
1082			 *     for the tag and that that entry is for the
1083			 *     widest potential data type the tag may have.
1084			 */
1085			{ TIFFDataType type = fip->field_type;
1086			  if (type != TIFF_LONG && type != TIFF_SLONG) {
1087				uint16 v = (uint16)
1088			   TIFFExtractData(tif, dp->tdir_type, dp->tdir_offset);
1089				ok = (fip->field_passcount ?
1090				    TIFFSetField(tif, dp->tdir_tag, 1, &v)
1091				  : TIFFSetField(tif, dp->tdir_tag, v));
1092				break;
1093			  }
1094			}
1095			/* fall thru... */
1096		case TIFF_LONG:
1097		case TIFF_SLONG:
1098			{ uint32 v32 =
1099		    TIFFExtractData(tif, dp->tdir_type, dp->tdir_offset);
1100			  ok = (fip->field_passcount ?
1101			      TIFFSetField(tif, dp->tdir_tag, 1, &v32)
1102			    : TIFFSetField(tif, dp->tdir_tag, v32));
1103			}
1104			break;
1105		case TIFF_RATIONAL:
1106		case TIFF_SRATIONAL:
1107		case TIFF_FLOAT:
1108			{ float v = (dp->tdir_type == TIFF_FLOAT ?
1109			      TIFFFetchFloat(tif, dp)
1110			    : TIFFFetchRational(tif, dp));
1111			  ok = (fip->field_passcount ?
1112			      TIFFSetField(tif, dp->tdir_tag, 1, &v)
1113			    : TIFFSetField(tif, dp->tdir_tag, v));
1114			}
1115			break;
1116		case TIFF_DOUBLE:
1117			{ double v;
1118			  ok = (TIFFFetchDoubleArray(tif, dp, &v) &&
1119			    (fip->field_passcount ?
1120			      TIFFSetField(tif, dp->tdir_tag, 1, &v)
1121			    : TIFFSetField(tif, dp->tdir_tag, v))
1122			  );
1123			}
1124			break;
1125		case TIFF_ASCII:
1126		case TIFF_UNDEFINED:		/* bit of a cheat... */
1127			{ char c[2];
1128			  if( (ok = (TIFFFetchString(tif, dp, c) != 0)) != 0 ){
1129				c[1] = '\0';		/* XXX paranoid */
1130				ok = TIFFSetField(tif, dp->tdir_tag, c);
1131			  }
1132			}
1133			break;
1134		}
1135	}
1136	return (ok);
1137}
1138
1139#define	NITEMS(x)	(sizeof (x) / sizeof (x[0]))
1140/*
1141 * Fetch samples/pixel short values for
1142 * the specified tag and verify that
1143 * all values are the same.
1144 */
1145static int
1146TIFFFetchPerSampleShorts(TIFF* tif, TIFFDirEntry* dir, int* pl)
1147{
1148	int samples = tif->tif_dir.td_samplesperpixel;
1149	int status = 0;
1150
1151	if (CheckDirCount(tif, dir, (uint32) samples)) {
1152		uint16 buf[10];
1153		uint16* v = buf;
1154
1155		if (samples > (int)NITEMS(buf))
1156			v=(uint16*) _TIFFmalloc(tif, samples * sizeof (uint16));
1157		if (TIFFFetchShortArray(tif, dir, v)) {
1158			int i;
1159			for (i = 1; i < samples; i++)
1160				if (v[i] != v[0]) {
1161					TIFFError(tif->tif_name,
1162		"Cannot handle different per-sample values for field \"%s\"",
1163			   _TIFFFieldWithTag(tif, dir->tdir_tag)->field_name);
1164					goto bad;
1165				}
1166			*pl = v[0];
1167			status = 1;
1168		}
1169	bad:
1170		if (v != buf)
1171			_TIFFfree(tif, (char*) v);
1172	}
1173	return (status);
1174}
1175
1176/*
1177 * Fetch samples/pixel ANY values for
1178 * the specified tag and verify that
1179 * all values are the same.
1180 */
1181static int
1182TIFFFetchPerSampleAnys(TIFF* tif, TIFFDirEntry* dir, double* pl)
1183{
1184	int samples = (int) tif->tif_dir.td_samplesperpixel;
1185	int status = 0;
1186
1187	if (CheckDirCount(tif, dir, (uint32) samples)) {
1188		double buf[10];
1189		double* v = buf;
1190
1191		if (samples > (int)NITEMS(buf))
1192			v=(double*) _TIFFmalloc(tif, samples * sizeof (double));
1193		if (TIFFFetchAnyArray(tif, dir, v)) {
1194			int i;
1195			for (i = 1; i < samples; i++)
1196				if (v[i] != v[0]) {
1197					TIFFError(tif->tif_name,
1198		"Cannot handle different per-sample values for field \"%s\"",
1199			   _TIFFFieldWithTag(tif, dir->tdir_tag)->field_name);
1200					goto bad;
1201				}
1202			*pl = v[0];
1203			status = 1;
1204		}
1205	bad:
1206		if (v != buf)
1207			_TIFFfree(tif, v);
1208	}
1209	return (status);
1210}
1211#undef NITEMS
1212
1213/*
1214 * Fetch a set of offsets or lengths.
1215 * While this routine says "strips",
1216 * in fact it's also used for tiles.
1217 */
1218static int
1219TIFFFetchStripThing(TIFF* tif, TIFFDirEntry* dir, long nstrips, uint32** lpp)
1220{
1221	register uint32* lp;
1222	int status;
1223
1224	if (!CheckDirCount(tif, dir, (uint32) nstrips))
1225		return (0);
1226	/*
1227	 * Allocate space for strip information.
1228	 */
1229	if (*lpp == NULL &&
1230	    (*lpp = (uint32 *)CheckMalloc(tif,
1231	      nstrips * sizeof (uint32), "for strip array")) == NULL)
1232		return (0);
1233	lp = *lpp;
1234	if (dir->tdir_type == (int)TIFF_SHORT) {
1235		/*
1236		 * Handle uint16->uint32 expansion.
1237		 */
1238		uint16* dp = (uint16*) CheckMalloc(tif,
1239		    dir->tdir_count* sizeof (uint16), "to fetch strip tag");
1240		if (dp == NULL)
1241			return (0);
1242		if( (status = TIFFFetchShortArray(tif, dir, dp)) != 0 ) {
1243			register uint16* wp = dp;
1244			while (nstrips-- > 0)
1245				*lp++ = *wp++;
1246		}
1247		_TIFFfree(tif, (char*) dp);
1248	} else
1249		status = TIFFFetchLongArray(tif, dir, lp);
1250	return (status);
1251}
1252
1253#define	NITEMS(x)	(sizeof (x) / sizeof (x[0]))
1254/*
1255 * Fetch and set the ExtraSamples tag.
1256 */
1257static int
1258TIFFFetchExtraSamples(TIFF* tif, TIFFDirEntry* dir)
1259{
1260	uint16 buf[10];
1261	uint16* v = buf;
1262	int status;
1263
1264	if (dir->tdir_count > NITEMS(buf))
1265		v=(uint16*) _TIFFmalloc(tif, dir->tdir_count * sizeof (uint16));
1266	if (dir->tdir_type == TIFF_BYTE)
1267		status = TIFFFetchByteArray(tif, dir, v);
1268	else
1269		status = TIFFFetchShortArray(tif, dir, v);
1270	if (status)
1271		status = TIFFSetField(tif, dir->tdir_tag, dir->tdir_count, v);
1272	if (v != buf)
1273		_TIFFfree(tif, (char*) v);
1274	return (status);
1275}
1276#undef NITEMS
1277
1278#ifdef COLORIMETRY_SUPPORT
1279/*
1280 * Fetch and set the RefBlackWhite tag.
1281 */
1282static int
1283TIFFFetchRefBlackWhite(TIFF* tif, TIFFDirEntry* dir)
1284{
1285	static const char mesg[] = "for \"ReferenceBlackWhite\" array";
1286	char* cp;
1287	int ok;
1288
1289	if (dir->tdir_type == TIFF_RATIONAL)
1290		return (TIFFFetchNormalTag(tif, dir));
1291	/*
1292	 * Handle LONG's for backward compatibility.
1293	 */
1294	cp = CheckMalloc(tif, dir->tdir_count * sizeof (uint32), mesg);
1295	if( (ok = (cp && TIFFFetchLongArray(tif, dir, (uint32*) cp))) != 0) {
1296		float* fp = (float*)
1297		    CheckMalloc(tif, dir->tdir_count * sizeof (float), mesg);
1298		if( (ok = (fp != NULL)) != 0 ) {
1299			uint32 i;
1300			for (i = 0; i < dir->tdir_count; i++)
1301				fp[i] = (float)((uint32*) cp)[i];
1302			ok = TIFFSetField(tif, dir->tdir_tag, fp);
1303			_TIFFfree(tif, (char*) fp);
1304		}
1305	}
1306	if (cp)
1307		_TIFFfree(tif, cp);
1308	return (ok);
1309}
1310#endif
1311
1312/*
1313 * Replace a single strip (tile) of uncompressed data by
1314 * multiple strips (tiles), each approximately 8Kbytes.
1315 * This is useful for dealing with large images or
1316 * for dealing with machines with a limited amount
1317 * memory.
1318 */
1319static void
1320ChopUpSingleUncompressedStrip(TIFF* tif)
1321{
1322	register TIFFDirectory *td = &tif->tif_dir;
1323	uint32 bytecount = td->td_stripbytecount[0];
1324	uint32 offset = td->td_stripoffset[0];
1325	tsize_t rowbytes = TIFFVTileSize(tif, 1), stripbytes;
1326	tstrip_t strip, nstrips, rowsperstrip;
1327	uint32* newcounts;
1328	uint32* newoffsets;
1329
1330	/*
1331	 * Make the rows hold at least one
1332	 * scanline, but fill 8k if possible.
1333	 */
1334	if (rowbytes > 8192) {
1335		stripbytes = rowbytes;
1336		rowsperstrip = 1;
1337	} else {
1338		rowsperstrip = 8192 / rowbytes;
1339		stripbytes = rowbytes * rowsperstrip;
1340	}
1341	/* never increase the number of strips in an image */
1342	if (rowsperstrip >= td->td_rowsperstrip)
1343		return;
1344	nstrips = (tstrip_t) TIFFhowmany(bytecount, stripbytes);
1345	newcounts = (uint32*) CheckMalloc(tif, nstrips * sizeof (uint32),
1346				"for chopped \"StripByteCounts\" array");
1347	newoffsets = (uint32*) CheckMalloc(tif, nstrips * sizeof (uint32),
1348				"for chopped \"StripOffsets\" array");
1349	if (newcounts == NULL || newoffsets == NULL) {
1350	        /*
1351		 * Unable to allocate new strip information, give
1352		 * up and use the original one strip information.
1353		 */
1354		if (newcounts != NULL)
1355			_TIFFfree(tif, newcounts);
1356		if (newoffsets != NULL)
1357			_TIFFfree(tif, newoffsets);
1358		return;
1359	}
1360	/*
1361	 * Fill the strip information arrays with
1362	 * new bytecounts and offsets that reflect
1363	 * the broken-up format.
1364	 */
1365	for (strip = 0; strip < nstrips; strip++) {
1366		if (stripbytes > (tsize_t) bytecount)
1367			stripbytes = bytecount;
1368		newcounts[strip] = stripbytes;
1369		newoffsets[strip] = offset;
1370		offset += stripbytes;
1371		bytecount -= stripbytes;
1372	}
1373	/*
1374	 * Replace old single strip info with multi-strip info.
1375	 */
1376	td->td_stripsperimage = td->td_nstrips = nstrips;
1377	TIFFSetField(tif, TIFFTAG_ROWSPERSTRIP, rowsperstrip);
1378
1379	_TIFFfree(tif, td->td_stripbytecount);
1380	_TIFFfree(tif, td->td_stripoffset);
1381	td->td_stripbytecount = newcounts;
1382	td->td_stripoffset = newoffsets;
1383}
1384