src/tiff/tif_zip.c

/* $Header$ */

/*
 * Copyright (c) 1995-1997 Sam Leffler
 * Copyright (c) 1995-1997 Silicon Graphics, Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and
 * its documentation for any purpose is hereby granted without fee, provided
 * that (i) the above copyright notices and this permission notice appear in
 * all copies of the software and related documentation, and (ii) the names of
 * Sam Leffler and Silicon Graphics may not be used in any advertising or
 * publicity relating to the software without the specific, prior written
 * permission of Sam Leffler and Silicon Graphics.
 *
 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
 *
 * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 */

#include "tiffiop.h"
#ifdef ZIP_SUPPORT
/*
 * TIFF Library.
 *
 * ZIP (aka Deflate) Compression Support
 *
 * This file is simply an interface to the zlib library written by
 * Jean-loup Gailly and Mark Adler.  You must use version 1.0 or later
 * of the library: this code assumes the 1.0 API and also depends on
 * the ability to write the zlib header multiple times (one per strip)
 * which was not possible with versions prior to 0.95.  Note also that
 * older versions of this codec avoided this bug by supressing the header
 * entirely.  This means that files written with the old library cannot
 * be read; they should be converted to a different compression scheme
 * and then reconverted.
 *
 * The data format used by the zlib library is described in the files
 * zlib-3.1.doc, deflate-1.1.doc and gzip-4.1.doc, available in the
 * directory ftp://ftp.uu.net/pub/archiving/zip/doc.  The library was
 * last found at ftp://ftp.uu.net/pub/archiving/zip/zlib/zlib-0.99.tar.gz.
 */
#include "tif_predict.h"
#include "zlib.h"

#include <stdio.h>
#include <assert.h>

/*
 * Sigh, ZLIB_VERSION is defined as a string so there's no
 * way to do a proper check here.  Instead we guess based
 * on the presence of #defines that were added between the
 * 0.95 and 1.0 distributions.
 */
#if !defined(Z_NO_COMPRESSION) || !defined(Z_DEFLATED)
#error "Antiquated ZLIB software; you must use version 1.0 or later"
#endif

/*
 * State block for each open TIFF
 * file using ZIP compression/decompression.
 */
typedef	struct {
	TIFFPredictorState predict;
	z_stream	stream;
	int		zipquality;		/* compression level */
	int		state;			/* state flags */
#define	ZSTATE_INIT	0x1		/* zlib setup successfully */

	TIFFVGetMethod	vgetparent;		/* super-class method */
	TIFFVSetMethod	vsetparent;		/* super-class method */
} ZIPState;

#define	ZState(tif)		((ZIPState*) (tif)->tif_data)
#define	DecoderState(tif)	ZState(tif)
#define	EncoderState(tif)	ZState(tif)

static	int ZIPEncode(TIFF*, tidata_t, tsize_t, tsample_t);
static	int ZIPDecode(TIFF*, tidata_t, tsize_t, tsample_t);

static int
ZIPSetupDecode(TIFF* tif)
{
	ZIPState* sp = DecoderState(tif);
	static const char module[] = "ZIPSetupDecode";

	assert(sp != NULL);
	if (inflateInit(&sp->stream) != Z_OK) {
		TIFFError(module, "%s: %s", tif->tif_name, sp->stream.msg);
		return (0);
	} else {
		sp->state |= ZSTATE_INIT;
		return (1);
	}
}

/*
 * Setup state for decoding a strip.
 */
static int
ZIPPreDecode(TIFF* tif, tsample_t s)
{
	ZIPState* sp = DecoderState(tif);

	(void) s;
	assert(sp != NULL);
	sp->stream.next_in = tif->tif_rawdata;
	sp->stream.avail_in = tif->tif_rawcc;
	return (inflateReset(&sp->stream) == Z_OK);
}

static int
ZIPDecode(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s)
{
	ZIPState* sp = DecoderState(tif);
	static const char module[] = "ZIPDecode";

	(void) s;
	assert(sp != NULL);
	sp->stream.next_out = op;
	sp->stream.avail_out = occ;
	do {
		int state = inflate(&sp->stream, Z_PARTIAL_FLUSH);
		if (state == Z_STREAM_END)
			break;
		if (state == Z_DATA_ERROR) {
			TIFFError(module,
			    "%s: Decoding error at scanline %d, %s",
			    tif->tif_name, tif->tif_row, sp->stream.msg);
			if (inflateSync(&sp->stream) != Z_OK)
				return (0);
			continue;
		}
		if (state != Z_OK) {
			TIFFError(module, "%s: zlib error: %s",
			    tif->tif_name, sp->stream.msg);
			return (0);
		}
	} while (sp->stream.avail_out > 0);
	if (sp->stream.avail_out != 0) {
		TIFFError(module,
		    "%s: Not enough data at scanline %d (short %d bytes)",
		    tif->tif_name, tif->tif_row, sp->stream.avail_out);
		return (0);
	}
	return (1);
}

static int
ZIPSetupEncode(TIFF* tif)
{
	ZIPState* sp = EncoderState(tif);
	static const char module[] = "ZIPSetupEncode";

	assert(sp != NULL);
	if (deflateInit(&sp->stream, sp->zipquality) != Z_OK) {
		TIFFError(module, "%s: %s", tif->tif_name, sp->stream.msg);
		return (0);
	} else {
		sp->state |= ZSTATE_INIT;
		return (1);
	}
}

/*
 * Reset encoding state at the start of a strip.
 */
static int
ZIPPreEncode(TIFF* tif, tsample_t s)
{
	ZIPState *sp = EncoderState(tif);

	(void) s;
	assert(sp != NULL);
	sp->stream.next_out = tif->tif_rawdata;
	sp->stream.avail_out = tif->tif_rawdatasize;
	return (deflateReset(&sp->stream) == Z_OK);
}

/*
 * Encode a chunk of pixels.
 */
static int
ZIPEncode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
{
	ZIPState *sp = EncoderState(tif);
	static const char module[] = "ZIPEncode";

	(void) s;
	sp->stream.next_in = bp;
	sp->stream.avail_in = cc;
	do {
		if (deflate(&sp->stream, Z_NO_FLUSH) != Z_OK) {
			TIFFError(module, "%s: Encoder error: %s",
			    tif->tif_name, sp->stream.msg);
			return (0);
		}
		if (sp->stream.avail_out == 0) {
			tif->tif_rawcc = tif->tif_rawdatasize;
			TIFFFlushData1(tif);
			sp->stream.next_out = tif->tif_rawdata;
			sp->stream.avail_out = tif->tif_rawdatasize;
		}
	} while (sp->stream.avail_in > 0);
	return (1);
}

/*
 * Finish off an encoded strip by flushing the last
 * string and tacking on an End Of Information code.
 */
static int
ZIPPostEncode(TIFF* tif)
{
	ZIPState *sp = EncoderState(tif);
	static const char module[] = "ZIPPostEncode";
	int state;

	sp->stream.avail_in = 0;
	do {
		state = deflate(&sp->stream, Z_FINISH);
		switch (state) {
		case Z_STREAM_END:
		case Z_OK:
		    if (sp->stream.avail_out != tif->tif_rawdatasize) {
			    tif->tif_rawcc =
				tif->tif_rawdatasize - sp->stream.avail_out;
			    TIFFFlushData1(tif);
			    sp->stream.next_out = tif->tif_rawdata;
			    sp->stream.avail_out = tif->tif_rawdatasize;
		    }
		    break;
		default:
		    TIFFError(module, "%s: zlib error: %s",
			tif->tif_name, sp->stream.msg);
		    return (0);
		}
	} while (state != Z_STREAM_END);
	return (1);
}

static void
ZIPCleanup(TIFF* tif)
{
	ZIPState* sp = ZState(tif);
	if (sp) {
		if (sp->state&ZSTATE_INIT) {
			/* NB: avoid problems in the library */
			if (tif->tif_mode == O_RDONLY)
				inflateEnd(&sp->stream);
			else
				deflateEnd(&sp->stream);
		}
		_TIFFfree(sp);
		tif->tif_data = NULL;
	}
}

static int
ZIPVSetField(TIFF* tif, ttag_t tag, va_list ap)
{
	ZIPState* sp = ZState(tif);
	static const char module[] = "ZIPVSetField";

	switch (tag) {
	case TIFFTAG_ZIPQUALITY:
		sp->zipquality = va_arg(ap, int);
		if (tif->tif_mode != O_RDONLY && (sp->state&ZSTATE_INIT)) {
			if (deflateParams(&sp->stream,
			    sp->zipquality, Z_DEFAULT_STRATEGY) != Z_OK) {
				TIFFError(module, "%s: zlib error: %s",
				    tif->tif_name, sp->stream.msg);
				return (0);
			}
		}
		return (1);
	default:
		return (*sp->vsetparent)(tif, tag, ap);
	}
	/*NOTREACHED*/
}

static int
ZIPVGetField(TIFF* tif, ttag_t tag, va_list ap)
{
	ZIPState* sp = ZState(tif);

	switch (tag) {
	case TIFFTAG_ZIPQUALITY:
		*va_arg(ap, int*) = sp->zipquality;
		break;
	default:
		return (*sp->vgetparent)(tif, tag, ap);
	}
	return (1);
}

static const TIFFFieldInfo zipFieldInfo[] = {
    { TIFFTAG_ZIPQUALITY,	 0, 0,	TIFF_ANY,	FIELD_PSEUDO,
      TRUE,	FALSE,	"" },
};
#define	N(a)	(sizeof (a) / sizeof (a[0]))

int
TIFFInitZIP(TIFF* tif, int scheme)
{
	ZIPState* sp;

	assert(scheme == COMPRESSION_DEFLATE);

	/*
	 * Allocate state block so tag methods have storage to record values.
	 */
	tif->tif_data = (tidata_t) _TIFFmalloc(sizeof (ZIPState));
	if (tif->tif_data == NULL)
		goto bad;
	sp = ZState(tif);
	sp->stream.zalloc = NULL;
	sp->stream.zfree = NULL;
	sp->stream.opaque = NULL;
	sp->stream.data_type = Z_BINARY;

	/*
	 * Merge codec-specific tag information and
	 * override parent get/set field methods.
	 */
	_TIFFMergeFieldInfo(tif, zipFieldInfo, N(zipFieldInfo));
	sp->vgetparent = tif->tif_vgetfield;
	tif->tif_vgetfield = ZIPVGetField;	/* hook for codec tags */
	sp->vsetparent = tif->tif_vsetfield;
	tif->tif_vsetfield = ZIPVSetField;	/* hook for codec tags */

	/* Default values for codec-specific fields */
	sp->zipquality = Z_DEFAULT_COMPRESSION;	/* default comp. level */
	sp->state = 0;

	/*
	 * Install codec methods.
	 */
	tif->tif_setupdecode = ZIPSetupDecode;
	tif->tif_predecode = ZIPPreDecode;
	tif->tif_decoderow = ZIPDecode;
	tif->tif_decodestrip = ZIPDecode;
	tif->tif_decodetile = ZIPDecode;
	tif->tif_setupencode = ZIPSetupEncode;
	tif->tif_preencode = ZIPPreEncode;
	tif->tif_postencode = ZIPPostEncode;
	tif->tif_encoderow = ZIPEncode;
	tif->tif_encodestrip = ZIPEncode;
	tif->tif_encodetile = ZIPEncode;
	tif->tif_cleanup = ZIPCleanup;
	/*
	 * Setup predictor setup.
	 */
	(void) TIFFPredictorInit(tif);
	return (1);
bad:
	TIFFError("TIFFInitZIP", "No space for ZIP state block");
	return (0);
}
#endif /* ZIP_SUPORT */
Commit	Line	Data
	1	/* $Header$ */
	2
	3	/*
	4	* Copyright (c) 1995-1997 Sam Leffler
	5	* Copyright (c) 1995-1997 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	#include "tiffiop.h"
	28	#ifdef ZIP_SUPPORT
	29	/*
	30	* TIFF Library.
	31	*
	32	* ZIP (aka Deflate) Compression Support
	33	*
	34	* This file is simply an interface to the zlib library written by
	35	* Jean-loup Gailly and Mark Adler. You must use version 1.0 or later
	36	* of the library: this code assumes the 1.0 API and also depends on
	37	* the ability to write the zlib header multiple times (one per strip)
	38	* which was not possible with versions prior to 0.95. Note also that
	39	* older versions of this codec avoided this bug by supressing the header
	40	* entirely. This means that files written with the old library cannot
	41	* be read; they should be converted to a different compression scheme
	42	* and then reconverted.
	43	*
	44	* The data format used by the zlib library is described in the files
	45	* zlib-3.1.doc, deflate-1.1.doc and gzip-4.1.doc, available in the
	46	* directory ftp://ftp.uu.net/pub/archiving/zip/doc. The library was
	47	* last found at ftp://ftp.uu.net/pub/archiving/zip/zlib/zlib-0.99.tar.gz.
	48	*/
	49	#include "tif_predict.h"
	50	#include "zlib.h"
	51
	52	#include <stdio.h>
	53	#include <assert.h>
	54
	55	/*
	56	* Sigh, ZLIB_VERSION is defined as a string so there's no
	57	* way to do a proper check here. Instead we guess based
	58	* on the presence of #defines that were added between the
	59	* 0.95 and 1.0 distributions.
	60	*/
	61	#if !defined(Z_NO_COMPRESSION) \|\| !defined(Z_DEFLATED)
	62	#error "Antiquated ZLIB software; you must use version 1.0 or later"
	63	#endif
	64
	65	/*
	66	* State block for each open TIFF
	67	* file using ZIP compression/decompression.
	68	*/
	69	typedef struct {
	70	TIFFPredictorState predict;
	71	z_stream stream;
	72	int zipquality; /* compression level */
	73	int state; /* state flags */
	74	#define ZSTATE_INIT 0x1 /* zlib setup successfully */
	75
	76	TIFFVGetMethod vgetparent; /* super-class method */
	77	TIFFVSetMethod vsetparent; /* super-class method */
	78	} ZIPState;
	79
	80	#define ZState(tif) ((ZIPState*) (tif)->tif_data)
	81	#define DecoderState(tif) ZState(tif)
	82	#define EncoderState(tif) ZState(tif)
	83
	84	static int ZIPEncode(TIFF*, tidata_t, tsize_t, tsample_t);
	85	static int ZIPDecode(TIFF*, tidata_t, tsize_t, tsample_t);
	86
	87	static int
	88	ZIPSetupDecode(TIFF* tif)
	89	{
	90	ZIPState* sp = DecoderState(tif);
	91	static const char module[] = "ZIPSetupDecode";
	92
	93	assert(sp != NULL);
	94	if (inflateInit(&sp->stream) != Z_OK) {
	95	TIFFError(module, "%s: %s", tif->tif_name, sp->stream.msg);
	96	return (0);
	97	} else {
	98	sp->state \|= ZSTATE_INIT;
	99	return (1);
	100	}
	101	}
	102
	103	/*
	104	* Setup state for decoding a strip.
	105	*/
	106	static int
	107	ZIPPreDecode(TIFF* tif, tsample_t s)
	108	{
	109	ZIPState* sp = DecoderState(tif);
	110
	111	(void) s;
	112	assert(sp != NULL);
	113	sp->stream.next_in = tif->tif_rawdata;
	114	sp->stream.avail_in = tif->tif_rawcc;
	115	return (inflateReset(&sp->stream) == Z_OK);
	116	}
	117
	118	static int
	119	ZIPDecode(TIFF* tif, tidata_t op, tsize_t occ, tsample_t s)
	120	{
	121	ZIPState* sp = DecoderState(tif);
	122	static const char module[] = "ZIPDecode";
	123
	124	(void) s;
	125	assert(sp != NULL);
	126	sp->stream.next_out = op;
	127	sp->stream.avail_out = occ;
	128	do {
	129	int state = inflate(&sp->stream, Z_PARTIAL_FLUSH);
	130	if (state == Z_STREAM_END)
	131	break;
	132	if (state == Z_DATA_ERROR) {
	133	TIFFError(module,
	134	"%s: Decoding error at scanline %d, %s",
	135	tif->tif_name, tif->tif_row, sp->stream.msg);
	136	if (inflateSync(&sp->stream) != Z_OK)
	137	return (0);
	138	continue;
	139	}
	140	if (state != Z_OK) {
	141	TIFFError(module, "%s: zlib error: %s",
	142	tif->tif_name, sp->stream.msg);
	143	return (0);
	144	}
	145	} while (sp->stream.avail_out > 0);
	146	if (sp->stream.avail_out != 0) {
	147	TIFFError(module,
	148	"%s: Not enough data at scanline %d (short %d bytes)",
	149	tif->tif_name, tif->tif_row, sp->stream.avail_out);
	150	return (0);
	151	}
	152	return (1);
	153	}
	154
	155	static int
	156	ZIPSetupEncode(TIFF* tif)
	157	{
	158	ZIPState* sp = EncoderState(tif);
	159	static const char module[] = "ZIPSetupEncode";
	160
	161	assert(sp != NULL);
	162	if (deflateInit(&sp->stream, sp->zipquality) != Z_OK) {
	163	TIFFError(module, "%s: %s", tif->tif_name, sp->stream.msg);
	164	return (0);
	165	} else {
	166	sp->state \|= ZSTATE_INIT;
	167	return (1);
	168	}
	169	}
	170
	171	/*
	172	* Reset encoding state at the start of a strip.
	173	*/
	174	static int
	175	ZIPPreEncode(TIFF* tif, tsample_t s)
	176	{
	177	ZIPState *sp = EncoderState(tif);
	178
	179	(void) s;
	180	assert(sp != NULL);
	181	sp->stream.next_out = tif->tif_rawdata;
	182	sp->stream.avail_out = tif->tif_rawdatasize;
	183	return (deflateReset(&sp->stream) == Z_OK);
	184	}
	185
	186	/*
	187	* Encode a chunk of pixels.
	188	*/
	189	static int
	190	ZIPEncode(TIFF* tif, tidata_t bp, tsize_t cc, tsample_t s)
	191	{
	192	ZIPState *sp = EncoderState(tif);
	193	static const char module[] = "ZIPEncode";
	194
	195	(void) s;
	196	sp->stream.next_in = bp;
	197	sp->stream.avail_in = cc;
	198	do {
	199	if (deflate(&sp->stream, Z_NO_FLUSH) != Z_OK) {
	200	TIFFError(module, "%s: Encoder error: %s",
	201	tif->tif_name, sp->stream.msg);
	202	return (0);
	203	}
	204	if (sp->stream.avail_out == 0) {
	205	tif->tif_rawcc = tif->tif_rawdatasize;
	206	TIFFFlushData1(tif);
	207	sp->stream.next_out = tif->tif_rawdata;
	208	sp->stream.avail_out = tif->tif_rawdatasize;
	209	}
	210	} while (sp->stream.avail_in > 0);
	211	return (1);
	212	}
	213
	214	/*
	215	* Finish off an encoded strip by flushing the last
	216	* string and tacking on an End Of Information code.
	217	*/
	218	static int
	219	ZIPPostEncode(TIFF* tif)
	220	{
	221	ZIPState *sp = EncoderState(tif);
	222	static const char module[] = "ZIPPostEncode";
	223	int state;
	224
	225	sp->stream.avail_in = 0;
	226	do {
	227	state = deflate(&sp->stream, Z_FINISH);
	228	switch (state) {
	229	case Z_STREAM_END:
	230	case Z_OK:
	231	if (sp->stream.avail_out != tif->tif_rawdatasize) {
	232	tif->tif_rawcc =
	233	tif->tif_rawdatasize - sp->stream.avail_out;
	234	TIFFFlushData1(tif);
	235	sp->stream.next_out = tif->tif_rawdata;
	236	sp->stream.avail_out = tif->tif_rawdatasize;
	237	}
	238	break;
	239	default:
	240	TIFFError(module, "%s: zlib error: %s",
	241	tif->tif_name, sp->stream.msg);
	242	return (0);
	243	}
	244	} while (state != Z_STREAM_END);
	245	return (1);
	246	}
	247
	248	static void
	249	ZIPCleanup(TIFF* tif)
	250	{
	251	ZIPState* sp = ZState(tif);
	252	if (sp) {
	253	if (sp->state&ZSTATE_INIT) {
	254	/* NB: avoid problems in the library */
	255	if (tif->tif_mode == O_RDONLY)
	256	inflateEnd(&sp->stream);
	257	else
	258	deflateEnd(&sp->stream);
	259	}
	260	_TIFFfree(sp);
	261	tif->tif_data = NULL;
	262	}
	263	}
	264
	265	static int
	266	ZIPVSetField(TIFF* tif, ttag_t tag, va_list ap)
	267	{
	268	ZIPState* sp = ZState(tif);
	269	static const char module[] = "ZIPVSetField";
	270
	271	switch (tag) {
	272	case TIFFTAG_ZIPQUALITY:
	273	sp->zipquality = va_arg(ap, int);
	274	if (tif->tif_mode != O_RDONLY && (sp->state&ZSTATE_INIT)) {
	275	if (deflateParams(&sp->stream,
	276	sp->zipquality, Z_DEFAULT_STRATEGY) != Z_OK) {
	277	TIFFError(module, "%s: zlib error: %s",
	278	tif->tif_name, sp->stream.msg);
	279	return (0);
	280	}
	281	}
	282	return (1);
	283	default:
	284	return (*sp->vsetparent)(tif, tag, ap);
	285	}
	286	/NOTREACHED/
	287	}
	288
	289	static int
	290	ZIPVGetField(TIFF* tif, ttag_t tag, va_list ap)
	291	{
	292	ZIPState* sp = ZState(tif);
	293
	294	switch (tag) {
	295	case TIFFTAG_ZIPQUALITY:
	296	va_arg(ap, int) = sp->zipquality;
	297	break;
	298	default:
	299	return (*sp->vgetparent)(tif, tag, ap);
	300	}
	301	return (1);
	302	}
	303
	304	static const TIFFFieldInfo zipFieldInfo[] = {
	305	{ TIFFTAG_ZIPQUALITY, 0, 0, TIFF_ANY, FIELD_PSEUDO,
	306	TRUE, FALSE, "" },
	307	};
	308	#define N(a) (sizeof (a) / sizeof (a[0]))
	309
	310	int
	311	TIFFInitZIP(TIFF* tif, int scheme)
	312	{
	313	ZIPState* sp;
	314
	315	assert(scheme == COMPRESSION_DEFLATE);
	316
	317	/*
	318	* Allocate state block so tag methods have storage to record values.
	319	*/
	320	tif->tif_data = (tidata_t) _TIFFmalloc(sizeof (ZIPState));
	321	if (tif->tif_data == NULL)
	322	goto bad;
	323	sp = ZState(tif);
	324	sp->stream.zalloc = NULL;
	325	sp->stream.zfree = NULL;
	326	sp->stream.opaque = NULL;
	327	sp->stream.data_type = Z_BINARY;
	328
	329	/*
	330	* Merge codec-specific tag information and
	331	* override parent get/set field methods.
	332	*/
	333	_TIFFMergeFieldInfo(tif, zipFieldInfo, N(zipFieldInfo));
	334	sp->vgetparent = tif->tif_vgetfield;
	335	tif->tif_vgetfield = ZIPVGetField; /* hook for codec tags */
	336	sp->vsetparent = tif->tif_vsetfield;
	337	tif->tif_vsetfield = ZIPVSetField; /* hook for codec tags */
	338
	339	/* Default values for codec-specific fields */
	340	sp->zipquality = Z_DEFAULT_COMPRESSION; /* default comp. level */
	341	sp->state = 0;
	342
	343	/*
	344	* Install codec methods.
	345	*/
	346	tif->tif_setupdecode = ZIPSetupDecode;
	347	tif->tif_predecode = ZIPPreDecode;
	348	tif->tif_decoderow = ZIPDecode;
	349	tif->tif_decodestrip = ZIPDecode;
	350	tif->tif_decodetile = ZIPDecode;
	351	tif->tif_setupencode = ZIPSetupEncode;
	352	tif->tif_preencode = ZIPPreEncode;
	353	tif->tif_postencode = ZIPPostEncode;
	354	tif->tif_encoderow = ZIPEncode;
	355	tif->tif_encodestrip = ZIPEncode;
	356	tif->tif_encodetile = ZIPEncode;
	357	tif->tif_cleanup = ZIPCleanup;
	358	/*
	359	* Setup predictor setup.
	360	*/
	361	(void) TIFFPredictorInit(tif);
	362	return (1);
	363	bad:
	364	TIFFError("TIFFInitZIP", "No space for ZIP state block");
	365	return (0);
	366	}
	367	#endif /* ZIP_SUPORT */