tif_dirwrite.c

一个国人自己实现图像库的程序（有参考价值）

/* $Header: /cvsroot/osrs/libtiff/libtiff/tif_dirwrite.c,v 1.9 2001/09/26 17:42:18 warmerda Exp $ */

/*
 * Copyright (c) 1988-1997 Sam Leffler
 * Copyright (c) 1991-1997 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.
 */

/*
 * TIFF Library.
 *
 * Directory Write Support Routines.
 */
#include "tiffiop.h"

#if HAVE_IEEEFP
#define	TIFFCvtNativeToIEEEFloat(tif, n, fp)
#define	TIFFCvtNativeToIEEEDouble(tif, n, dp)
#else
extern	void TIFFCvtNativeToIEEEFloat(TIFF*, uint32, float*);
extern	void TIFFCvtNativeToIEEEDouble(TIFF*, uint32, double*);
#endif

static	int TIFFWriteNormalTag(TIFF*, TIFFDirEntry*, const TIFFFieldInfo*);
static	void TIFFSetupShortLong(TIFF*, ttag_t, TIFFDirEntry*, uint32);
static	int TIFFSetupShortPair(TIFF*, ttag_t, TIFFDirEntry*);
static	int TIFFWritePerSampleShorts(TIFF*, ttag_t, TIFFDirEntry*);
static	int TIFFWritePerSampleAnys(TIFF*, TIFFDataType, ttag_t, TIFFDirEntry*);
static	int TIFFWriteShortTable(TIFF*, ttag_t, TIFFDirEntry*, uint32, uint16**);
static	int TIFFWriteShortArray(TIFF*,
	    TIFFDataType, ttag_t, TIFFDirEntry*, uint32, uint16*);
static	int TIFFWriteLongArray(TIFF *,
	    TIFFDataType, ttag_t, TIFFDirEntry*, uint32, uint32*);
static	int TIFFWriteRationalArray(TIFF *,
	    TIFFDataType, ttag_t, TIFFDirEntry*, uint32, float*);
static	int TIFFWriteFloatArray(TIFF *,
	    TIFFDataType, ttag_t, TIFFDirEntry*, uint32, float*);
static	int TIFFWriteDoubleArray(TIFF *,
	    TIFFDataType, ttag_t, TIFFDirEntry*, uint32, double*);
static	int TIFFWriteByteArray(TIFF*, TIFFDirEntry*, char*);
static	int TIFFWriteAnyArray(TIFF*,
	    TIFFDataType, ttag_t, TIFFDirEntry*, uint32, double*);
#ifdef COLORIMETRY_SUPPORT
static	int TIFFWriteTransferFunction(TIFF*, TIFFDirEntry*);
#endif
#ifdef CMYK_SUPPORT
static	int TIFFWriteInkNames(TIFF*, TIFFDirEntry*);
#endif
static	int TIFFWriteData(TIFF*, TIFFDirEntry*, char*);
static	int TIFFLinkDirectory(TIFF*);

#define	WriteRationalPair(type, tag1, v1, tag2, v2) {		\
	if (!TIFFWriteRational(tif, type, tag1, dir, v1))	\
		goto bad;					\
	if (!TIFFWriteRational(tif, type, tag2, dir+1, v2))	\
		goto bad;					\
	dir++;							\
}
#define	TIFFWriteRational(tif, type, tag, dir, v) \
	TIFFWriteRationalArray((tif), (type), (tag), (dir), 1, &(v))
#ifndef TIFFWriteRational
static	int TIFFWriteRational(TIFF*,
	    TIFFDataType, ttag_t, TIFFDirEntry*, float);
#endif

/*
 * Write the contents of the current directory
 * to the specified file.  This routine doesn't
 * handle overwriting a directory with auxiliary
 * storage that's been changed.
 */
int
TIFFWriteDirectory(TIFF* tif)
{
	uint16 dircount;
	toff_t diroff;
	ttag_t tag;
	uint32 nfields;
	tsize_t dirsize;
	char* data;
	TIFFDirEntry* dir;
	TIFFDirectory* td;
	u_long b, fields[FIELD_SETLONGS];
	int fi, nfi;

	if (tif->tif_mode == O_RDONLY)
		return (1);
	/*
	 * Clear write state so that subsequent images with
	 * different characteristics get the right buffers
	 * setup for them.
	 */
	if (tif->tif_flags & TIFF_POSTENCODE) {
		tif->tif_flags &= ~TIFF_POSTENCODE;
		if (!(*tif->tif_postencode)(tif)) {
			TIFFError(tif->tif_name,
			    "Error post-encoding before directory write");
			return (0);
		}
	}
	(*tif->tif_close)(tif);			/* shutdown encoder */
	/*
	 * Flush any data that might have been written
	 * by the compression close+cleanup routines.
	 */
	if (tif->tif_rawcc > 0 && !TIFFFlushData1(tif)) {
		TIFFError(tif->tif_name,
		    "Error flushing data before directory write");
		return (0);
	}
	if ((tif->tif_flags & TIFF_MYBUFFER) && tif->tif_rawdata) {
		_TIFFfree(tif->tif_rawdata);
		tif->tif_rawdata = NULL;
		tif->tif_rawcc = 0;
                tif->tif_rawdatasize = 0;
	}
	tif->tif_flags &= ~(TIFF_BEENWRITING|TIFF_BUFFERSETUP);

	td = &tif->tif_dir;
	/*
	 * Size the directory so that we can calculate
	 * offsets for the data items that aren't kept
	 * in-place in each field.
	 */
	nfields = 0;
	for (b = 0; b <= FIELD_LAST; b++)
		if (TIFFFieldSet(tif, b))
			nfields += (b < FIELD_SUBFILETYPE ? 2 : 1);
	dirsize = nfields * sizeof (TIFFDirEntry);
	data = (char*) _TIFFmalloc(dirsize);
	if (data == NULL) {
		TIFFError(tif->tif_name,
		    "Cannot write directory, out of space");
		return (0);
	}
	/*
	 * Directory hasn't been placed yet, put
	 * it at the end of the file and link it
	 * into the existing directory structure.
	 */
	if (tif->tif_diroff == 0 && !TIFFLinkDirectory(tif))
		goto bad;
	tif->tif_dataoff = (toff_t)(
	    tif->tif_diroff + sizeof (uint16) + dirsize + sizeof (toff_t));
	if (tif->tif_dataoff & 1)
		tif->tif_dataoff++;
	(void) TIFFSeekFile(tif, tif->tif_dataoff, SEEK_SET);
	tif->tif_curdir++;
	dir = (TIFFDirEntry*) data;
	/*
	 * Setup external form of directory
	 * entries and write data items.
	 */
	_TIFFmemcpy(fields, td->td_fieldsset, sizeof (fields));
	/*
	 * Write out ExtraSamples tag only if
	 * extra samples are present in the data.
	 */
	if (FieldSet(fields, FIELD_EXTRASAMPLES) && !td->td_extrasamples) {
		ResetFieldBit(fields, FIELD_EXTRASAMPLES);
		nfields--;
		dirsize -= sizeof (TIFFDirEntry);
	}								/*XXX*/
	for (fi = 0, nfi = tif->tif_nfields; nfi > 0; nfi--, fi++) {
		const TIFFFieldInfo* fip = tif->tif_fieldinfo[fi];
		if (!FieldSet(fields, fip->field_bit))
			continue;
		switch (fip->field_bit) {
		case FIELD_STRIPOFFSETS:
			/*
			 * We use one field bit for both strip and tile
			 * offsets, and so must be careful in selecting
			 * the appropriate field descriptor (so that tags
			 * are written in sorted order).
			 */
			tag = isTiled(tif) ?
			    TIFFTAG_TILEOFFSETS : TIFFTAG_STRIPOFFSETS;
			if (tag != fip->field_tag)
				continue;
			if (!TIFFWriteLongArray(tif, TIFF_LONG, tag, dir,
			    (uint32) td->td_nstrips, td->td_stripoffset))
				goto bad;
			break;
		case FIELD_STRIPBYTECOUNTS:
			/*
			 * We use one field bit for both strip and tile
			 * byte counts, and so must be careful in selecting
			 * the appropriate field descriptor (so that tags
			 * are written in sorted order).
			 */
			tag = isTiled(tif) ?
			    TIFFTAG_TILEBYTECOUNTS : TIFFTAG_STRIPBYTECOUNTS;
			if (tag != fip->field_tag)
				continue;
			if (!TIFFWriteLongArray(tif, TIFF_LONG, tag, dir,
			    (uint32) td->td_nstrips, td->td_stripbytecount))
				goto bad;
			break;
		case FIELD_ROWSPERSTRIP:
			TIFFSetupShortLong(tif, TIFFTAG_ROWSPERSTRIP,
			    dir, td->td_rowsperstrip);
			break;
		case FIELD_COLORMAP:
			if (!TIFFWriteShortTable(tif, TIFFTAG_COLORMAP, dir,
			    3, td->td_colormap))
				goto bad;
			break;
		case FIELD_IMAGEDIMENSIONS:
			TIFFSetupShortLong(tif, TIFFTAG_IMAGEWIDTH,
			    dir++, td->td_imagewidth);
			TIFFSetupShortLong(tif, TIFFTAG_IMAGELENGTH,
			    dir, td->td_imagelength);
			break;
		case FIELD_TILEDIMENSIONS:
			TIFFSetupShortLong(tif, TIFFTAG_TILEWIDTH,
			    dir++, td->td_tilewidth);
			TIFFSetupShortLong(tif, TIFFTAG_TILELENGTH,
			    dir, td->td_tilelength);
			break;
		case FIELD_POSITION:
			WriteRationalPair(TIFF_RATIONAL,
			    TIFFTAG_XPOSITION, td->td_xposition,
			    TIFFTAG_YPOSITION, td->td_yposition);
			break;
		case FIELD_RESOLUTION:
			WriteRationalPair(TIFF_RATIONAL,
			    TIFFTAG_XRESOLUTION, td->td_xresolution,
			    TIFFTAG_YRESOLUTION, td->td_yresolution);
			break;
		case FIELD_BITSPERSAMPLE:
		case FIELD_MINSAMPLEVALUE:
		case FIELD_MAXSAMPLEVALUE:
		case FIELD_SAMPLEFORMAT:
			if (!TIFFWritePerSampleShorts(tif, fip->field_tag, dir))
				goto bad;
			break;
		case FIELD_SMINSAMPLEVALUE:
		case FIELD_SMAXSAMPLEVALUE:
			if (!TIFFWritePerSampleAnys(tif,
			    _TIFFSampleToTagType(tif), fip->field_tag, dir))
				goto bad;
			break;
		case FIELD_PAGENUMBER:
		case FIELD_HALFTONEHINTS:
#ifdef YCBCR_SUPPORT
		case FIELD_YCBCRSUBSAMPLING:
#endif
#ifdef CMYK_SUPPORT
		case FIELD_DOTRANGE:
#endif
			if (!TIFFSetupShortPair(tif, fip->field_tag, dir))
				goto bad;
			break;
#ifdef CMYK_SUPPORT
		case FIELD_INKNAMES:
			if (!TIFFWriteInkNames(tif, dir))
				goto bad;
			break;
#endif
#ifdef COLORIMETRY_SUPPORT
		case FIELD_TRANSFERFUNCTION:
			if (!TIFFWriteTransferFunction(tif, dir))
				goto bad;
			break;
#endif
#if SUBIFD_SUPPORT
		case FIELD_SUBIFD:
			if (!TIFFWriteNormalTag(tif, dir, fip))
				goto bad;
			/*
			 * Total hack: if this directory includes a SubIFD
			 * tag then force the next <n> directories to be
			 * written as ``sub directories'' of this one.  This
			 * is used to write things like thumbnails and
			 * image masks that one wants to keep out of the
			 * normal directory linkage access mechanism.
			 */
			if (dir->tdir_count > 0) {
				tif->tif_flags |= TIFF_INSUBIFD;
				tif->tif_nsubifd = (uint16) dir->tdir_count;
				if (dir->tdir_count > 1)
					tif->tif_subifdoff = dir->tdir_offset;
				else
					tif->tif_subifdoff = (uint32)(
					      tif->tif_diroff
					    + sizeof (uint16)
					    + ((char*)&dir->tdir_offset-data));
			}
			break;
#endif
		default:
			if (!TIFFWriteNormalTag(tif, dir, fip))
				goto bad;
			break;
		}
		dir++;
		ResetFieldBit(fields, fip->field_bit);
	}
	/*
	 * Write directory.
	 */
	dircount = (uint16) nfields;
	diroff = (uint32) tif->tif_nextdiroff;
	if (tif->tif_flags & TIFF_SWAB) {
		/*
		 * The file's byte order is opposite to the
		 * native machine architecture.  We overwrite
		 * the directory information with impunity
		 * because it'll be released below after we
		 * write it to the file.  Note that all the
		 * other tag construction routines assume that
		 * we do this byte-swapping; i.e. they only
		 * byte-swap indirect data.
		 */
		for (dir = (TIFFDirEntry*) data; dircount; dir++, dircount--) {
			TIFFSwabArrayOfShort(&dir->tdir_tag, 2);
			TIFFSwabArrayOfLong(&dir->tdir_count, 2);
		}
		dircount = (uint16) nfields;
		TIFFSwabShort(&dircount);
		TIFFSwabLong(&diroff);
	}
	(void) TIFFSeekFile(tif, tif->tif_diroff, SEEK_SET);
	if (!WriteOK(tif, &dircount, sizeof (dircount))) {
		TIFFError(tif->tif_name, "Error writing directory count");
		goto bad;
	}
	if (!WriteOK(tif, data, dirsize)) {
		TIFFError(tif->tif_name, "Error writing directory contents");
		goto bad;
	}
	if (!WriteOK(tif, &diroff, sizeof (diroff))) {
		TIFFError(tif->tif_name, "Error writing directory link");
		goto bad;
	}
	TIFFFreeDirectory(tif);
	_TIFFfree(data);
	tif->tif_flags &= ~TIFF_DIRTYDIRECT;
	(*tif->tif_cleanup)(tif);

	/*
	 * Reset directory-related state for subsequent
	 * directories.
	 */
        TIFFCreateDirectory(tif);
	return (1);
bad:
	_TIFFfree(data);
	return (0);
}