/* $Header: /usr/people/sam/tiff/libtiff/RCS/tif_zip.c,v 1.8 1996/03/07 17:00:23 sam Rel $ */

/*
 * Copyright (c) 1995-1996 Sam Leffler
 * Copyright (c) 1995-1996 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"

/*
 * 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"
#undef EXPORT
#include "zlib.h"

#include <assert.h>
#include "imgInt.h"

#ifdef __WIN32__
#define Z_LIB_NAME "zlib.dll"
#else
#define WINAPI /**/
#endif

#ifndef Z_LIB_NAME
#define Z_LIB_NAME "libz.so"
#endif

/*
 * 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)

/*
 * Stuff to support dynamical loading of libz.
 */

static struct LibzFunctions {
    VOID *handle;
    int (WINAPI * deflate) _ANSI_ARGS_((z_streamp, int));
    int (WINAPI * dInit) _ANSI_ARGS_((z_streamp, int, CONST char *, int));
    int (WINAPI * deflateReset) _ANSI_ARGS_((z_streamp));
    int (WINAPI * deflateParams) _ANSI_ARGS_((z_streamp, int, int));
    int (WINAPI * deflateEnd) _ANSI_ARGS_((z_streamp));
    int (WINAPI * inflate) _ANSI_ARGS_((z_streamp, int));
    int (WINAPI * iInit) _ANSI_ARGS_((z_streamp, CONST char *, int));
    int (WINAPI * inflateReset) _ANSI_ARGS_((z_streamp));
    int (WINAPI * inflateSync) _ANSI_ARGS_((z_streamp));
    int (WINAPI * inflateEnd) _ANSI_ARGS_((z_streamp));
} zlib = {0};

static char *symbols[] = {
    "deflate",
    "deflateInit_",
    "deflateReset",
    "deflateParams",
    "deflateEnd",
    "inflate",
    "inflateInit_",
    "inflateReset",
    "inflateSync",
    "inflateEnd",
    (char *) NULL
};

extern void ImgTIFFfree _ANSI_ARGS_((tdata_t data));
extern tdata_t ImgTIFFmalloc _ANSI_ARGS_((tsize_t size));
extern tdata_t ImgTIFFrealloc _ANSI_ARGS_((tdata_t data, tsize_t size));
extern void ImgTIFFError _ANSI_ARGS_(TCL_VARARGS(CONST char *, module));
extern int ImgTIFFPredictorInit _ANSI_ARGS_((TIFF *tif));
extern void ImgTIFFMergeFieldInfo _ANSI_ARGS_((TIFF* tif, CONST VOID *voidp, int i));
extern int ImgTIFFFlushData1 _ANSI_ARGS_((TIFF *tif));

static int ZIPSetupDecode _ANSI_ARGS_((TIFF* tif));

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

	assert(sp != NULL);
	if (zlib.iInit(&sp->stream, ZLIB_VERSION, sizeof(z_stream)) != Z_OK) {
		ImgTIFFError(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
#ifdef _USING_PROTOTYPES_
ZIPPreDecode (
    TIFF* tif,
    tsample_t s)
#else
ZIPPreDecode(tif, s)
    TIFF* tif;
    tsample_t s;
#endif
{
	ZIPState* sp = DecoderState(tif);

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

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

	(void) s;
	assert(sp != NULL);
	sp->stream.next_out = op;
	sp->stream.avail_out = occ;
	do {
		int state = zlib.inflate(&sp->stream, Z_PARTIAL_FLUSH);
		if (state == Z_STREAM_END)
			break;
		if (state == Z_DATA_ERROR) {
			ImgTIFFError(module,
			    "%s: Decoding error at scanline %d, %s",
			    tif->tif_name, tif->tif_row, sp->stream.msg);
			if (zlib.inflateSync(&sp->stream) != Z_OK)
				return (0);
			continue;
		}
		if (state != Z_OK) {
			ImgTIFFError(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) {
		ImgTIFFError(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
#ifdef _USING_PROTOTYPES_
ZIPSetupEncode (
    TIFF* tif)
#else
ZIPSetupEncode(tif)
    TIFF* tif;
#endif
{
	ZIPState* sp = EncoderState(tif);
	static char module[] = "ZIPSetupEncode";

	assert(sp != NULL);
	if (zlib.dInit(&sp->stream, sp->zipquality, ZLIB_VERSION, sizeof(z_stream)) != Z_OK) {
		ImgTIFFError(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
#ifdef _USING_PROTOTYPES_
ZIPPreEncode (
    TIFF* tif,
    tsample_t s)
#else
ZIPPreEncode(tif, s)
    TIFF* tif;
    tsample_t s;
#endif
{
	ZIPState *sp = EncoderState(tif);

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

/*
 * Encode a chunk of pixels.
 */

static int
#ifdef _USING_PROTOTYPES_
ZIPEncode (TIFF* tif,
    tidata_t bp,
    tsize_t cc,
    tsample_t s)
#else
ZIPEncode(tif, bp, cc, s)
    TIFF* tif;
    tidata_t bp;
    tsize_t cc;
    tsample_t s;
#endif
{
	ZIPState *sp = EncoderState(tif);
	static char module[] = "ZIPEncode";

	(void) s;
	sp->stream.next_in = bp;
	sp->stream.avail_in = cc;
	do {
		if (zlib.deflate(&sp->stream, Z_NO_FLUSH) != Z_OK) {
			ImgTIFFError(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;
			ImgTIFFFlushData1(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 _ANSI_ARGS_((TIFF* tif));

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

	sp->stream.avail_in = 0;
	do {
		state = zlib.deflate(&sp->stream, Z_FINISH);
		switch (state) {
		case Z_STREAM_END:
		case Z_OK:
		    if ((int) sp->stream.avail_out != tif->tif_rawdatasize) {
			    tif->tif_rawcc =
				tif->tif_rawdatasize - sp->stream.avail_out;
			    ImgTIFFFlushData1(tif);
			    sp->stream.next_out = tif->tif_rawdata;
			    sp->stream.avail_out = tif->tif_rawdatasize;
		    }
		    break;
		default:
		    ImgTIFFError(module, "%s: zlib error: %s",
			tif->tif_name, sp->stream.msg);
		    return (0);
		}
	} while (state != Z_STREAM_END);
	return (1);
}

static void ZIPCleanup _ANSI_ARGS_((TIFF* tif));

static void
ZIPCleanup(tif)
    TIFF* tif;
{
	ZIPState* sp = ZState(tif);
	if (sp) {
		if (tif->tif_mode == O_RDONLY)
			zlib.inflateEnd(&sp->stream);
		else
			zlib.deflateEnd(&sp->stream);
		ImgTIFFfree(sp);
		tif->tif_data = NULL;
	}
}

static int ZIPVSetField _ANSI_ARGS_((TIFF* tif, ttag_t tag, va_list ap));

static int
ZIPVSetField(tif, tag, ap)
    TIFF* tif;
    ttag_t tag;
    va_list ap;
{
	ZIPState* sp = ZState(tif);
	static 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 (zlib.deflateParams(&sp->stream,
			    sp->zipquality, Z_DEFAULT_STRATEGY) != Z_OK) {
				ImgTIFFError(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 _ANSI_ARGS_((TIFF* tif, ttag_t tag, va_list ap));

static int
ZIPVGetField(tif, tag, ap)
    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]))

static voidpf
ZipAlloc(opaque, items, size)
    voidpf opaque;
    uInt items;
    uInt size;
{
    return (voidpf) ImgTIFFmalloc((tsize_t)(items * size));
}

static void
ZipFree(opaque, address)
    voidpf opaque;
    voidpf address;
{
    ImgTIFFfree((tdata_t) address);
}

int
ImgInitTIFFzip(handle, scheme)
    VOID * handle;
    int scheme;
{
	TIFF* tif = (TIFF *) handle;
	ZIPState* sp;

	assert(scheme == COMPRESSION_DEFLATE);

	if (ImgLoadLib(NULL, Z_LIB_NAME, &zlib.handle, symbols, 10)
		!= TCL_OK) {
	    ImgTIFFError("", "%s: Cannot load %s", tif->tif_name, Z_LIB_NAME);
	    return (0);
	}
	/*
	 * Allocate state block so tag methods have storage to record values.
	 */
	tif->tif_data = (tidata_t) ImgTIFFmalloc(sizeof (ZIPState));
	if (tif->tif_data == NULL)
		goto bad;
	sp = ZState(tif);
	sp->stream.zalloc = ZipAlloc;
	sp->stream.zfree = ZipFree;
	sp->stream.opaque = NULL;
	sp->stream.data_type = Z_BINARY;

	/*
	 * Merge codec-specific tag information and
	 * override parent get/set field methods.
	 */
	ImgTIFFMergeFieldInfo(tif, (CONST VOID *) 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) ImgTIFFPredictorInit(tif);
	return (1);
bad:
	ImgTIFFError("TIFFInitZIP", "No space for ZIP state block");
	return (0);
}