[wxWidgets.git] / src / tiff / tif_read.c

/* $Header$ */

/*
 * 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.
 * Scanline-oriented Read Support
 */
#include "tiffiop.h"
#include <stdio.h>
#include <assert.h>

static	int TIFFFillStrip(TIFF*, tstrip_t);
static	int TIFFFillTile(TIFF*, ttile_t);
static	int TIFFStartStrip(TIFF*, tstrip_t);
static	int TIFFStartTile(TIFF*, ttile_t);
static	int TIFFCheckRead(TIFF*, int);

#define	NOSTRIP	((tstrip_t) -1)			/* undefined state */
#define	NOTILE	((ttile_t) -1)			/* undefined state */

/*
 * Seek to a random row+sample in a file.
 */
static int
TIFFSeek(TIFF* tif, uint32 row, tsample_t sample)
{
	register TIFFDirectory *td = &tif->tif_dir;
	tstrip_t strip;

	if (row >= td->td_imagelength) {	/* out of range */
		TIFFError(tif->tif_name, "%lu: Row out of range, max %lu",
		    (u_long) row, (u_long) td->td_imagelength);
		return (0);
	}
	if (td->td_planarconfig == PLANARCONFIG_SEPARATE) {
		if (sample >= td->td_samplesperpixel) {
			TIFFError(tif->tif_name,
			    "%lu: Sample out of range, max %lu",
			    (u_long) sample, (u_long) td->td_samplesperpixel);
			return (0);
		}
		strip = sample*td->td_stripsperimage + row/td->td_rowsperstrip;
	} else
		strip = row / td->td_rowsperstrip;
	if (strip != tif->tif_curstrip) { 	/* different strip, refill */
		if (!TIFFFillStrip(tif, strip))
			return (0);
	} else if (row < tif->tif_row) {
		/*
		 * Moving backwards within the same strip: backup
		 * to the start and then decode forward (below).
		 *
		 * NB: If you're planning on lots of random access within a
		 * strip, it's better to just read and decode the entire
		 * strip, and then access the decoded data in a random fashion.
		 */
		if (!TIFFStartStrip(tif, strip))
			return (0);
	}
	if (row != tif->tif_row) {
		/*
		 * Seek forward to the desired row.
		 */
		if (!(*tif->tif_seek)(tif, row - tif->tif_row))
			return (0);
		tif->tif_row = row;
	}
	return (1);
}

int
TIFFReadScanline(TIFF* tif, tdata_t buf, uint32 row, tsample_t sample)
{
	int e;

	if (!TIFFCheckRead(tif, 0))
		return (-1);
	if( (e = TIFFSeek(tif, row, sample)) != 0) {
		/*
		 * Decompress desired row into user buffer.
		 */
		e = (*tif->tif_decoderow)
		    (tif, (tidata_t) buf, tif->tif_scanlinesize, sample);
		tif->tif_row++;
		if (e)
			(*tif->tif_postdecode)(tif, (tidata_t) buf,
			    tif->tif_scanlinesize);
	}
	return (e > 0 ? 1 : -1);
}

/*
 * Read a strip of data and decompress the specified
 * amount into the user-supplied buffer.
 */
tsize_t
TIFFReadEncodedStrip(TIFF* tif, tstrip_t strip, tdata_t buf, tsize_t size)
{
	TIFFDirectory *td = &tif->tif_dir;
	uint32 nrows;
	tsize_t stripsize;

	if (!TIFFCheckRead(tif, 0))
		return (-1);
	if (strip >= td->td_nstrips) {
		TIFFError(tif->tif_name, "%ld: Strip out of range, max %ld",
		    (long) strip, (long) td->td_nstrips);
		return (-1);
	}
	/*
	 * Calculate the strip size according to the number of
	 * rows in the strip (check for truncated last strip).
	 */
	if (strip != td->td_nstrips-1 ||
	    (nrows = td->td_imagelength % td->td_rowsperstrip) == 0)
		nrows = td->td_rowsperstrip;
	stripsize = TIFFVStripSize(tif, nrows);
	if (size == (tsize_t) -1)
		size = stripsize;
	else if (size > stripsize)
		size = stripsize;
	if (TIFFFillStrip(tif, strip) && (*tif->tif_decodestrip)(tif,
	    (tidata_t) buf, size, (tsample_t)(strip / td->td_stripsperimage))) {
		(*tif->tif_postdecode)(tif, (tidata_t) buf, size);
		return (size);
	} else
		return ((tsize_t) -1);
}

static tsize_t
TIFFReadRawStrip1(TIFF* tif,
    tstrip_t strip, tdata_t buf, tsize_t size, const char* module)
{
	TIFFDirectory *td = &tif->tif_dir;

	if (!isMapped(tif)) {
		tsize_t cc;

		if (!SeekOK(tif, td->td_stripoffset[strip])) {
			TIFFError(module,
			    "%s: Seek error at scanline %lu, strip %lu",
			    tif->tif_name,
			    (u_long) tif->tif_row, (u_long) strip);
			return (-1);
		}
		cc = TIFFReadFile(tif, buf, size);
		if (cc != size) {
			TIFFError(module,
		"%s: Read error at scanline %lu; got %lu bytes, expected %lu",
			    tif->tif_name,
			    (u_long) tif->tif_row,
			    (u_long) cc,
			    (u_long) size);
			return (-1);
		}
	} else {
		if (td->td_stripoffset[strip] + size > tif->tif_size) {
			TIFFError(module,
    "%s: Read error at scanline %lu, strip %lu; got %lu bytes, expected %lu",
			    tif->tif_name,
			    (u_long) tif->tif_row,
			    (u_long) strip,
			    (u_long) tif->tif_size - td->td_stripoffset[strip],
			    (u_long) size);
			return (-1);
		}
		_TIFFmemcpy(buf, tif->tif_base + td->td_stripoffset[strip], size);
	}
	return (size);
}

/*
 * Read a strip of data from the file.
 */
tsize_t
TIFFReadRawStrip(TIFF* tif, tstrip_t strip, tdata_t buf, tsize_t size)
{
	static const char module[] = "TIFFReadRawStrip";
	TIFFDirectory *td = &tif->tif_dir;
	tsize_t bytecount;

	if (!TIFFCheckRead(tif, 0))
		return ((tsize_t) -1);
	if (strip >= td->td_nstrips) {
		TIFFError(tif->tif_name, "%lu: Strip out of range, max %lu",
		    (u_long) strip, (u_long) td->td_nstrips);
		return ((tsize_t) -1);
	}
	bytecount = td->td_stripbytecount[strip];
	if (bytecount <= 0) {
		TIFFError(tif->tif_name,
		    "%lu: Invalid strip byte count, strip %lu",
		    (u_long) bytecount, (u_long) strip);
		return ((tsize_t) -1);
	}
	if (size != (tsize_t)-1 && size < bytecount)
		bytecount = size;
	return (TIFFReadRawStrip1(tif, strip, buf, bytecount, module));
}

/*
 * Read the specified strip and setup for decoding. 
 * The data buffer is expanded, as necessary, to
 * hold the strip's data.
 */
static int
TIFFFillStrip(TIFF* tif, tstrip_t strip)
{
	static const char module[] = "TIFFFillStrip";
	TIFFDirectory *td = &tif->tif_dir;
	tsize_t bytecount;

	bytecount = td->td_stripbytecount[strip];
	if (bytecount <= 0) {
		TIFFError(tif->tif_name,
		    "%lu: Invalid strip byte count, strip %lu",
		    (u_long) bytecount, (u_long) strip);
		return (0);
	}
	if (isMapped(tif) &&
	    (isFillOrder(tif, td->td_fillorder) || (tif->tif_flags & TIFF_NOBITREV))) {
		/*
		 * The image is mapped into memory and we either don't
		 * need to flip bits or the compression routine is going
		 * to handle this operation itself.  In this case, avoid
		 * copying the raw data and instead just reference the
		 * data from the memory mapped file image.  This assumes
		 * that the decompression routines do not modify the
		 * contents of the raw data buffer (if they try to,
		 * the application will get a fault since the file is
		 * mapped read-only).
		 */
		if ((tif->tif_flags & TIFF_MYBUFFER) && tif->tif_rawdata)
			_TIFFfree(tif->tif_rawdata);
		tif->tif_flags &= ~TIFF_MYBUFFER;
		if (td->td_stripoffset[strip] + bytecount > tif->tif_size) {
			/*
			 * This error message might seem strange, but it's
			 * what would happen if a read were done instead.
			 */
			TIFFError(module,
		    "%s: Read error on strip %lu; got %lu bytes, expected %lu",
			    tif->tif_name,
			    (u_long) strip,
			    (u_long) tif->tif_size - td->td_stripoffset[strip],
			    (u_long) bytecount);
			tif->tif_curstrip = NOSTRIP;
			return (0);
		}
		tif->tif_rawdatasize = bytecount;
		tif->tif_rawdata = tif->tif_base + td->td_stripoffset[strip];
	} else {
		/*
		 * Expand raw data buffer, if needed, to
		 * hold data strip coming from file
		 * (perhaps should set upper bound on
		 *  the size of a buffer we'll use?).
		 */
		if (bytecount > tif->tif_rawdatasize) {
			tif->tif_curstrip = NOSTRIP;
			if ((tif->tif_flags & TIFF_MYBUFFER) == 0) {
				TIFFError(module,
				"%s: Data buffer too small to hold strip %lu",
				    tif->tif_name, (u_long) strip);
				return (0);
			}
			if (!TIFFReadBufferSetup(tif, 0,
			    TIFFroundup(bytecount, 1024)))
				return (0);
		}
		if (TIFFReadRawStrip1(tif, strip, (u_char *)tif->tif_rawdata,
		    bytecount, module) != bytecount)
			return (0);
		if (!isFillOrder(tif, td->td_fillorder) &&
		    (tif->tif_flags & TIFF_NOBITREV) == 0)
			TIFFReverseBits(tif->tif_rawdata, bytecount);
	}
	return (TIFFStartStrip(tif, strip));
}

/*
 * Tile-oriented Read Support
 * Contributed by Nancy Cam (Silicon Graphics).
 */

/*
 * Read and decompress a tile of data.  The
 * tile is selected by the (x,y,z,s) coordinates.
 */
tsize_t
TIFFReadTile(TIFF* tif,
    tdata_t buf, uint32 x, uint32 y, uint32 z, tsample_t s)
{
	if (!TIFFCheckRead(tif, 1) || !TIFFCheckTile(tif, x, y, z, s))
		return (-1);
	return (TIFFReadEncodedTile(tif,
	    TIFFComputeTile(tif, x, y, z, s), buf, (tsize_t) -1));
}

/*
 * Read a tile of data and decompress the specified
 * amount into the user-supplied buffer.
 */
tsize_t
TIFFReadEncodedTile(TIFF* tif, ttile_t tile, tdata_t buf, tsize_t size)
{
	TIFFDirectory *td = &tif->tif_dir;
	tsize_t tilesize = tif->tif_tilesize;

	if (!TIFFCheckRead(tif, 1))
		return (-1);
	if (tile >= td->td_nstrips) {
		TIFFError(tif->tif_name, "%ld: Tile out of range, max %ld",
		    (long) tile, (u_long) td->td_nstrips);
		return (-1);
	}
	if (size == (tsize_t) -1)
		size = tilesize;
	else if (size > tilesize)
		size = tilesize;
	if (TIFFFillTile(tif, tile) && (*tif->tif_decodetile)(tif,
	    (tidata_t) buf, size, (tsample_t)(tile/td->td_stripsperimage))) {
		(*tif->tif_postdecode)(tif, (tidata_t) buf, size);
		return (size);
	} else
		return (-1);
}

static tsize_t
TIFFReadRawTile1(TIFF* tif,
    ttile_t tile, tdata_t buf, tsize_t size, const char* module)
{
	TIFFDirectory *td = &tif->tif_dir;

	if (!isMapped(tif)) {
		tsize_t cc;

		if (!SeekOK(tif, td->td_stripoffset[tile])) {
			TIFFError(module,
			    "%s: Seek error at row %ld, col %ld, tile %ld",
			    tif->tif_name,
			    (long) tif->tif_row,
			    (long) tif->tif_col,
			    (long) tile);
			return ((tsize_t) -1);
		}
		cc = TIFFReadFile(tif, buf, size);
		if (cc != size) {
			TIFFError(module,
	    "%s: Read error at row %ld, col %ld; got %lu bytes, expected %lu",
			    tif->tif_name,
			    (long) tif->tif_row,
			    (long) tif->tif_col,
			    (u_long) cc,
			    (u_long) size);
			return ((tsize_t) -1);
		}
	} else {
		if (td->td_stripoffset[tile] + size > tif->tif_size) {
			TIFFError(module,
    "%s: Read error at row %ld, col %ld, tile %ld; got %lu bytes, expected %lu",
			    tif->tif_name,
			    (long) tif->tif_row,
			    (long) tif->tif_col,
			    (long) tile,
			    (u_long) tif->tif_size - td->td_stripoffset[tile],
			    (u_long) size);
			return ((tsize_t) -1);
		}
		_TIFFmemcpy(buf, tif->tif_base + td->td_stripoffset[tile], size);
	}
	return (size);
}

/*
 * Read a tile of data from the file.
 */
tsize_t
TIFFReadRawTile(TIFF* tif, ttile_t tile, tdata_t buf, tsize_t size)
{
	static const char module[] = "TIFFReadRawTile";
	TIFFDirectory *td = &tif->tif_dir;
	tsize_t bytecount;

	if (!TIFFCheckRead(tif, 1))
		return ((tsize_t) -1);
	if (tile >= td->td_nstrips) {
		TIFFError(tif->tif_name, "%lu: Tile out of range, max %lu",
		    (u_long) tile, (u_long) td->td_nstrips);
		return ((tsize_t) -1);
	}
	bytecount = td->td_stripbytecount[tile];
	if (size != (tsize_t) -1 && size < bytecount)
		bytecount = size;
	return (TIFFReadRawTile1(tif, tile, buf, bytecount, module));
}

/*
 * Read the specified tile and setup for decoding. 
 * The data buffer is expanded, as necessary, to
 * hold the tile's data.
 */
static int
TIFFFillTile(TIFF* tif, ttile_t tile)
{
	static const char module[] = "TIFFFillTile";
	TIFFDirectory *td = &tif->tif_dir;
	tsize_t bytecount;

	bytecount = td->td_stripbytecount[tile];
	if (bytecount <= 0) {
		TIFFError(tif->tif_name,
		    "%lu: Invalid tile byte count, tile %lu",
		    (u_long) bytecount, (u_long) tile);
		return (0);
	}
	if (isMapped(tif) &&
	    (isFillOrder(tif, td->td_fillorder) || (tif->tif_flags & TIFF_NOBITREV))) {
		/*
		 * The image is mapped into memory and we either don't
		 * need to flip bits or the compression routine is going
		 * to handle this operation itself.  In this case, avoid
		 * copying the raw data and instead just reference the
		 * data from the memory mapped file image.  This assumes
		 * that the decompression routines do not modify the
		 * contents of the raw data buffer (if they try to,
		 * the application will get a fault since the file is
		 * mapped read-only).
		 */
		if ((tif->tif_flags & TIFF_MYBUFFER) && tif->tif_rawdata)
			_TIFFfree(tif->tif_rawdata);
		tif->tif_flags &= ~TIFF_MYBUFFER;
		if (td->td_stripoffset[tile] + bytecount > tif->tif_size) {
			tif->tif_curtile = NOTILE;
			return (0);
		}
		tif->tif_rawdatasize = bytecount;
		tif->tif_rawdata = tif->tif_base + td->td_stripoffset[tile];
	} else {
		/*
		 * Expand raw data buffer, if needed, to
		 * hold data tile coming from file
		 * (perhaps should set upper bound on
		 *  the size of a buffer we'll use?).
		 */
		if (bytecount > tif->tif_rawdatasize) {
			tif->tif_curtile = NOTILE;
			if ((tif->tif_flags & TIFF_MYBUFFER) == 0) {
				TIFFError(module,
				"%s: Data buffer too small to hold tile %ld",
				    tif->tif_name, (long) tile);
				return (0);
			}
			if (!TIFFReadBufferSetup(tif, 0,
			    TIFFroundup(bytecount, 1024)))
				return (0);
		}
		if (TIFFReadRawTile1(tif, tile, (u_char *)tif->tif_rawdata,
		    bytecount, module) != bytecount)
			return (0);
		if (!isFillOrder(tif, td->td_fillorder) &&
		    (tif->tif_flags & TIFF_NOBITREV) == 0)
			TIFFReverseBits(tif->tif_rawdata, bytecount);
	}
	return (TIFFStartTile(tif, tile));
}

/*
 * Setup the raw data buffer in preparation for
 * reading a strip of raw data.  If the buffer
 * is specified as zero, then a buffer of appropriate
 * size is allocated by the library.  Otherwise,
 * the client must guarantee that the buffer is
 * large enough to hold any individual strip of
 * raw data.
 */
int
TIFFReadBufferSetup(TIFF* tif, tdata_t bp, tsize_t size)
{
	static const char module[] = "TIFFReadBufferSetup";

	if (tif->tif_rawdata) {
		if (tif->tif_flags & TIFF_MYBUFFER)
			_TIFFfree(tif->tif_rawdata);
		tif->tif_rawdata = NULL;
	}
	if (bp) {
		tif->tif_rawdatasize = size;
		tif->tif_rawdata = (tidata_t) bp;
		tif->tif_flags &= ~TIFF_MYBUFFER;
	} else {
		tif->tif_rawdatasize = TIFFroundup(size, 1024);
		tif->tif_rawdata = (tidata_t) _TIFFmalloc(tif->tif_rawdatasize);
		tif->tif_flags |= TIFF_MYBUFFER;
	}
	if (tif->tif_rawdata == NULL) {
		TIFFError(module,
		    "%s: No space for data buffer at scanline %ld",
		    tif->tif_name, (long) tif->tif_row);
		tif->tif_rawdatasize = 0;
		return (0);
	}
	return (1);
}

/*
 * Set state to appear as if a
 * strip has just been read in.
 */
static int
TIFFStartStrip(TIFF* tif, tstrip_t strip)
{
	TIFFDirectory *td = &tif->tif_dir;

	if ((tif->tif_flags & TIFF_CODERSETUP) == 0) {
		if (!(*tif->tif_setupdecode)(tif))
			return (0);
		tif->tif_flags |= TIFF_CODERSETUP;
	}
	tif->tif_curstrip = strip;
	tif->tif_row = (strip % td->td_stripsperimage) * td->td_rowsperstrip;
	tif->tif_rawcp = tif->tif_rawdata;
	tif->tif_rawcc = td->td_stripbytecount[strip];
	return ((*tif->tif_predecode)(tif,
			(tsample_t)(strip / td->td_stripsperimage)));
}

/*
 * Set state to appear as if a
 * tile has just been read in.
 */
static int
TIFFStartTile(TIFF* tif, ttile_t tile)
{
	TIFFDirectory *td = &tif->tif_dir;

	if ((tif->tif_flags & TIFF_CODERSETUP) == 0) {
		if (!(*tif->tif_setupdecode)(tif))
			return (0);
		tif->tif_flags |= TIFF_CODERSETUP;
	}
	tif->tif_curtile = tile;
	tif->tif_row =
	    (tile % TIFFhowmany(td->td_imagewidth, td->td_tilewidth)) *
		td->td_tilelength;
	tif->tif_col =
	    (tile % TIFFhowmany(td->td_imagelength, td->td_tilelength)) *
		td->td_tilewidth;
	tif->tif_rawcp = tif->tif_rawdata;
	tif->tif_rawcc = td->td_stripbytecount[tile];
	return ((*tif->tif_predecode)(tif,
			(tsample_t)(tile/td->td_stripsperimage)));
}

static int
TIFFCheckRead(TIFF* tif, int tiles)
{
	if (tif->tif_mode == O_WRONLY) {
		TIFFError(tif->tif_name, "File not open for reading");
		return (0);
	}
	if (tiles ^ isTiled(tif)) {
		TIFFError(tif->tif_name, tiles ?
		    "Can not read tiles from a stripped image" :
		    "Can not read scanlines from a tiled image");
		return (0);
	}
	return (1);
}

void
_TIFFNoPostDecode(TIFF* tif, tidata_t buf, tsize_t cc)
{
    (void) tif; (void) buf; (void) cc;
}

void
_TIFFSwab16BitData(TIFF* tif, tidata_t buf, tsize_t cc)
{
    (void) tif;
    assert((cc & 1) == 0);
    TIFFSwabArrayOfShort((uint16*) buf, cc/2);
}

void
_TIFFSwab32BitData(TIFF* tif, tidata_t buf, tsize_t cc)
{
    (void) tif;
    assert((cc & 3) == 0);
    TIFFSwabArrayOfLong((uint32*) buf, cc/4);
}

void
_TIFFSwab64BitData(TIFF* tif, tidata_t buf, tsize_t cc)
{
    (void) tif;
    assert((cc & 7) == 0);
    TIFFSwabArrayOfDouble((double*) buf, cc/8);
}
Commit	Line	Data
b47c832e RR	1	/* $Header$ */
	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	* Scanline-oriented Read Support
	30	*/
	31	#include "tiffiop.h"
	32	#include <stdio.h>
	33	#include <assert.h>
	34
	35	static int TIFFFillStrip(TIFF*, tstrip_t);
	36	static int TIFFFillTile(TIFF*, ttile_t);
	37	static int TIFFStartStrip(TIFF*, tstrip_t);
	38	static int TIFFStartTile(TIFF*, ttile_t);
	39	static int TIFFCheckRead(TIFF*, int);
	40
	41	#define NOSTRIP ((tstrip_t) -1) /* undefined state */
	42	#define NOTILE ((ttile_t) -1) /* undefined state */
	43
	44	/*
	45	* Seek to a random row+sample in a file.
	46	*/
	47	static int
	48	TIFFSeek(TIFF* tif, uint32 row, tsample_t sample)
	49	{
	50	register TIFFDirectory *td = &tif->tif_dir;
	51	tstrip_t strip;
	52
	53	if (row >= td->td_imagelength) { /* out of range */
	54	TIFFError(tif->tif_name, "%lu: Row out of range, max %lu",
	55	(u_long) row, (u_long) td->td_imagelength);
	56	return (0);
	57	}
	58	if (td->td_planarconfig == PLANARCONFIG_SEPARATE) {
	59	if (sample >= td->td_samplesperpixel) {
	60	TIFFError(tif->tif_name,
	61	"%lu: Sample out of range, max %lu",
	62	(u_long) sample, (u_long) td->td_samplesperpixel);
	63	return (0);
	64	}
65	strip = sample*td->td_stripsperimage + row/td->td_rowsperstrip;
66	} else
67	strip = row / td->td_rowsperstrip;
68	if (strip != tif->tif_curstrip) { /* different strip, refill */
69	if (!TIFFFillStrip(tif, strip))
70	return (0);
71	} else if (row < tif->tif_row) {
72	/*
73	* Moving backwards within the same strip: backup
74	* to the start and then decode forward (below).
75	*
76	* NB: If you're planning on lots of random access within a
77	* strip, it's better to just read and decode the entire
78	* strip, and then access the decoded data in a random fashion.
79	*/
80	if (!TIFFStartStrip(tif, strip))
81	return (0);
82	}
83	if (row != tif->tif_row) {
84	/*
85	* Seek forward to the desired row.
86	*/
87	if (!(*tif->tif_seek)(tif, row - tif->tif_row))
88	return (0);
89	tif->tif_row = row;
90	}
91	return (1);
92	}
93
94	int
95	TIFFReadScanline(TIFF* tif, tdata_t buf, uint32 row, tsample_t sample)
96	{
97	int e;
98
99	if (!TIFFCheckRead(tif, 0))
100	return (-1);
101	if( (e = TIFFSeek(tif, row, sample)) != 0) {
102	/*
103	* Decompress desired row into user buffer.
104	*/
105	e = (*tif->tif_decoderow)
106	(tif, (tidata_t) buf, tif->tif_scanlinesize, sample);
107	tif->tif_row++;
108	if (e)
109	(*tif->tif_postdecode)(tif, (tidata_t) buf,
110	tif->tif_scanlinesize);
111	}
112	return (e > 0 ? 1 : -1);
113	}
114
115	/*
116	* Read a strip of data and decompress the specified
117	* amount into the user-supplied buffer.
118	*/
119	tsize_t
120	TIFFReadEncodedStrip(TIFF* tif, tstrip_t strip, tdata_t buf, tsize_t size)
121	{
122	TIFFDirectory *td = &tif->tif_dir;
123	uint32 nrows;
124	tsize_t stripsize;
125
126	if (!TIFFCheckRead(tif, 0))
127	return (-1);
128	if (strip >= td->td_nstrips) {
129	TIFFError(tif->tif_name, "%ld: Strip out of range, max %ld",
130	(long) strip, (long) td->td_nstrips);
131	return (-1);
132	}
133	/*
134	* Calculate the strip size according to the number of
135	* rows in the strip (check for truncated last strip).
136	*/
137	if (strip != td->td_nstrips-1 \|\|
138	(nrows = td->td_imagelength % td->td_rowsperstrip) == 0)
139	nrows = td->td_rowsperstrip;
140	stripsize = TIFFVStripSize(tif, nrows);
141	if (size == (tsize_t) -1)
142	size = stripsize;
143	else if (size > stripsize)
144	size = stripsize;
145	if (TIFFFillStrip(tif, strip) && (*tif->tif_decodestrip)(tif,
146	(tidata_t) buf, size, (tsample_t)(strip / td->td_stripsperimage))) {
147	(*tif->tif_postdecode)(tif, (tidata_t) buf, size);
148	return (size);
149	} else
150	return ((tsize_t) -1);
151	}
152
153	static tsize_t
154	TIFFReadRawStrip1(TIFF* tif,
155	tstrip_t strip, tdata_t buf, tsize_t size, const char* module)
156	{
157	TIFFDirectory *td = &tif->tif_dir;
158
159	if (!isMapped(tif)) {
160	tsize_t cc;
161
162	if (!SeekOK(tif, td->td_stripoffset[strip])) {
163	TIFFError(module,
164	"%s: Seek error at scanline %lu, strip %lu",
165	tif->tif_name,
166	(u_long) tif->tif_row, (u_long) strip);
167	return (-1);
168	}
169	cc = TIFFReadFile(tif, buf, size);
170	if (cc != size) {
171	TIFFError(module,
172	"%s: Read error at scanline %lu; got %lu bytes, expected %lu",
173	tif->tif_name,
174	(u_long) tif->tif_row,
175	(u_long) cc,
176	(u_long) size);
177	return (-1);
178	}
179	} else {
180	if (td->td_stripoffset[strip] + size > tif->tif_size) {
181	TIFFError(module,
182	"%s: Read error at scanline %lu, strip %lu; got %lu bytes, expected %lu",
183	tif->tif_name,
184	(u_long) tif->tif_row,
185	(u_long) strip,
186	(u_long) tif->tif_size - td->td_stripoffset[strip],
187	(u_long) size);
188	return (-1);
189	}
190	_TIFFmemcpy(buf, tif->tif_base + td->td_stripoffset[strip], size);
191	}
192	return (size);
193	}
194
195	/*
196	* Read a strip of data from the file.
197	*/
198	tsize_t
199	TIFFReadRawStrip(TIFF* tif, tstrip_t strip, tdata_t buf, tsize_t size)
200	{
201	static const char module[] = "TIFFReadRawStrip";
202	TIFFDirectory *td = &tif->tif_dir;
203	tsize_t bytecount;
204
205	if (!TIFFCheckRead(tif, 0))
206	return ((tsize_t) -1);
207	if (strip >= td->td_nstrips) {
208	TIFFError(tif->tif_name, "%lu: Strip out of range, max %lu",
209	(u_long) strip, (u_long) td->td_nstrips);
210	return ((tsize_t) -1);
211	}
212	bytecount = td->td_stripbytecount[strip];
213	if (bytecount <= 0) {
214	TIFFError(tif->tif_name,
215	"%lu: Invalid strip byte count, strip %lu",
216	(u_long) bytecount, (u_long) strip);
217	return ((tsize_t) -1);
218	}
219	if (size != (tsize_t)-1 && size < bytecount)
220	bytecount = size;
221	return (TIFFReadRawStrip1(tif, strip, buf, bytecount, module));
222	}
223
224	/*
225	* Read the specified strip and setup for decoding.
226	* The data buffer is expanded, as necessary, to
227	* hold the strip's data.
228	*/
229	static int
230	TIFFFillStrip(TIFF* tif, tstrip_t strip)
231	{
232	static const char module[] = "TIFFFillStrip";
233	TIFFDirectory *td = &tif->tif_dir;
234	tsize_t bytecount;
235
236	bytecount = td->td_stripbytecount[strip];
237	if (bytecount <= 0) {
238	TIFFError(tif->tif_name,
239	"%lu: Invalid strip byte count, strip %lu",
240	(u_long) bytecount, (u_long) strip);
241	return (0);
242	}
243	if (isMapped(tif) &&
244	(isFillOrder(tif, td->td_fillorder) \|\| (tif->tif_flags & TIFF_NOBITREV))) {
245	/*
246	* The image is mapped into memory and we either don't
247	* need to flip bits or the compression routine is going
248	* to handle this operation itself. In this case, avoid
249	* copying the raw data and instead just reference the
250	* data from the memory mapped file image. This assumes
251	* that the decompression routines do not modify the
252	* contents of the raw data buffer (if they try to,
253	* the application will get a fault since the file is
254	* mapped read-only).
255	*/
256	if ((tif->tif_flags & TIFF_MYBUFFER) && tif->tif_rawdata)
257	_TIFFfree(tif->tif_rawdata);
258	tif->tif_flags &= ~TIFF_MYBUFFER;
259	if (td->td_stripoffset[strip] + bytecount > tif->tif_size) {
260	/*
261	* This error message might seem strange, but it's
262	* what would happen if a read were done instead.
263	*/
264	TIFFError(module,
265	"%s: Read error on strip %lu; got %lu bytes, expected %lu",
266	tif->tif_name,
267	(u_long) strip,
268	(u_long) tif->tif_size - td->td_stripoffset[strip],
269	(u_long) bytecount);
270	tif->tif_curstrip = NOSTRIP;
271	return (0);
272	}
273	tif->tif_rawdatasize = bytecount;
274	tif->tif_rawdata = tif->tif_base + td->td_stripoffset[strip];
275	} else {
276	/*
277	* Expand raw data buffer, if needed, to
278	* hold data strip coming from file
279	* (perhaps should set upper bound on
280	* the size of a buffer we'll use?).
281	*/
282	if (bytecount > tif->tif_rawdatasize) {
283	tif->tif_curstrip = NOSTRIP;
284	if ((tif->tif_flags & TIFF_MYBUFFER) == 0) {
285	TIFFError(module,
286	"%s: Data buffer too small to hold strip %lu",
287	tif->tif_name, (u_long) strip);
288	return (0);
289	}
290	if (!TIFFReadBufferSetup(tif, 0,
291	TIFFroundup(bytecount, 1024)))
292	return (0);
293	}
294	if (TIFFReadRawStrip1(tif, strip, (u_char *)tif->tif_rawdata,
295	bytecount, module) != bytecount)
296	return (0);
297	if (!isFillOrder(tif, td->td_fillorder) &&
298	(tif->tif_flags & TIFF_NOBITREV) == 0)
299	TIFFReverseBits(tif->tif_rawdata, bytecount);
300	}
301	return (TIFFStartStrip(tif, strip));
302	}
303
304	/*
305	* Tile-oriented Read Support
306	* Contributed by Nancy Cam (Silicon Graphics).
307	*/
308
309	/*
310	* Read and decompress a tile of data. The
311	* tile is selected by the (x,y,z,s) coordinates.
312	*/
313	tsize_t
314	TIFFReadTile(TIFF* tif,
315	tdata_t buf, uint32 x, uint32 y, uint32 z, tsample_t s)
316	{
317	if (!TIFFCheckRead(tif, 1) \|\| !TIFFCheckTile(tif, x, y, z, s))
318	return (-1);
319	return (TIFFReadEncodedTile(tif,
320	TIFFComputeTile(tif, x, y, z, s), buf, (tsize_t) -1));
321	}
322
323	/*
324	* Read a tile of data and decompress the specified
325	* amount into the user-supplied buffer.
326	*/
327	tsize_t
328	TIFFReadEncodedTile(TIFF* tif, ttile_t tile, tdata_t buf, tsize_t size)
329	{
330	TIFFDirectory *td = &tif->tif_dir;
331	tsize_t tilesize = tif->tif_tilesize;
332
333	if (!TIFFCheckRead(tif, 1))
334	return (-1);
335	if (tile >= td->td_nstrips) {
336	TIFFError(tif->tif_name, "%ld: Tile out of range, max %ld",
337	(long) tile, (u_long) td->td_nstrips);
338	return (-1);
339	}
340	if (size == (tsize_t) -1)
341	size = tilesize;
342	else if (size > tilesize)
343	size = tilesize;
344	if (TIFFFillTile(tif, tile) && (*tif->tif_decodetile)(tif,
345	(tidata_t) buf, size, (tsample_t)(tile/td->td_stripsperimage))) {
346	(*tif->tif_postdecode)(tif, (tidata_t) buf, size);
347	return (size);
348	} else
349	return (-1);
350	}
351
352	static tsize_t
353	TIFFReadRawTile1(TIFF* tif,
354	ttile_t tile, tdata_t buf, tsize_t size, const char* module)
355	{
356	TIFFDirectory *td = &tif->tif_dir;
357
358	if (!isMapped(tif)) {
359	tsize_t cc;
360
361	if (!SeekOK(tif, td->td_stripoffset[tile])) {
362	TIFFError(module,
363	"%s: Seek error at row %ld, col %ld, tile %ld",
364	tif->tif_name,
365	(long) tif->tif_row,
366	(long) tif->tif_col,
367	(long) tile);
368	return ((tsize_t) -1);
369	}
370	cc = TIFFReadFile(tif, buf, size);
371	if (cc != size) {
372	TIFFError(module,
373	"%s: Read error at row %ld, col %ld; got %lu bytes, expected %lu",
374	tif->tif_name,
375	(long) tif->tif_row,
376	(long) tif->tif_col,
377	(u_long) cc,
378	(u_long) size);
379	return ((tsize_t) -1);
380	}
381	} else {
382	if (td->td_stripoffset[tile] + size > tif->tif_size) {
383	TIFFError(module,
384	"%s: Read error at row %ld, col %ld, tile %ld; got %lu bytes, expected %lu",
385	tif->tif_name,
386	(long) tif->tif_row,
387	(long) tif->tif_col,
388	(long) tile,
389	(u_long) tif->tif_size - td->td_stripoffset[tile],
390	(u_long) size);
391	return ((tsize_t) -1);
392	}
393	_TIFFmemcpy(buf, tif->tif_base + td->td_stripoffset[tile], size);
394	}
395	return (size);
396	}
397
398	/*
399	* Read a tile of data from the file.
400	*/
401	tsize_t
402	TIFFReadRawTile(TIFF* tif, ttile_t tile, tdata_t buf, tsize_t size)
403	{
404	static const char module[] = "TIFFReadRawTile";
405	TIFFDirectory *td = &tif->tif_dir;
406	tsize_t bytecount;
407
408	if (!TIFFCheckRead(tif, 1))
409	return ((tsize_t) -1);
410	if (tile >= td->td_nstrips) {
411	TIFFError(tif->tif_name, "%lu: Tile out of range, max %lu",
412	(u_long) tile, (u_long) td->td_nstrips);
413	return ((tsize_t) -1);
414	}
415	bytecount = td->td_stripbytecount[tile];
416	if (size != (tsize_t) -1 && size < bytecount)
417	bytecount = size;
418	return (TIFFReadRawTile1(tif, tile, buf, bytecount, module));
419	}
420
421	/*
422	* Read the specified tile and setup for decoding.
423	* The data buffer is expanded, as necessary, to
424	* hold the tile's data.
425	*/
426	static int
427	TIFFFillTile(TIFF* tif, ttile_t tile)
428	{
429	static const char module[] = "TIFFFillTile";
430	TIFFDirectory *td = &tif->tif_dir;
431	tsize_t bytecount;
432
433	bytecount = td->td_stripbytecount[tile];
434	if (bytecount <= 0) {
435	TIFFError(tif->tif_name,
436	"%lu: Invalid tile byte count, tile %lu",
437	(u_long) bytecount, (u_long) tile);
438	return (0);
439	}
440	if (isMapped(tif) &&
441	(isFillOrder(tif, td->td_fillorder) \|\| (tif->tif_flags & TIFF_NOBITREV))) {
442	/*
443	* The image is mapped into memory and we either don't
444	* need to flip bits or the compression routine is going
445	* to handle this operation itself. In this case, avoid
446	* copying the raw data and instead just reference the
447	* data from the memory mapped file image. This assumes
448	* that the decompression routines do not modify the
449	* contents of the raw data buffer (if they try to,
450	* the application will get a fault since the file is
451	* mapped read-only).
452	*/
453	if ((tif->tif_flags & TIFF_MYBUFFER) && tif->tif_rawdata)
454	_TIFFfree(tif->tif_rawdata);
455	tif->tif_flags &= ~TIFF_MYBUFFER;
456	if (td->td_stripoffset[tile] + bytecount > tif->tif_size) {
457	tif->tif_curtile = NOTILE;
458	return (0);
459	}
460	tif->tif_rawdatasize = bytecount;
461	tif->tif_rawdata = tif->tif_base + td->td_stripoffset[tile];
462	} else {
463	/*
464	* Expand raw data buffer, if needed, to
465	* hold data tile coming from file
466	* (perhaps should set upper bound on
467	* the size of a buffer we'll use?).
468	*/
469	if (bytecount > tif->tif_rawdatasize) {
470	tif->tif_curtile = NOTILE;
471	if ((tif->tif_flags & TIFF_MYBUFFER) == 0) {
472	TIFFError(module,
473	"%s: Data buffer too small to hold tile %ld",
474	tif->tif_name, (long) tile);
475	return (0);
476	}
477	if (!TIFFReadBufferSetup(tif, 0,
478	TIFFroundup(bytecount, 1024)))
479	return (0);
480	}
481	if (TIFFReadRawTile1(tif, tile, (u_char *)tif->tif_rawdata,
482	bytecount, module) != bytecount)
483	return (0);
484	if (!isFillOrder(tif, td->td_fillorder) &&
485	(tif->tif_flags & TIFF_NOBITREV) == 0)
486	TIFFReverseBits(tif->tif_rawdata, bytecount);
487	}
488	return (TIFFStartTile(tif, tile));
489	}
490
491	/*
492	* Setup the raw data buffer in preparation for
493	* reading a strip of raw data. If the buffer
494	* is specified as zero, then a buffer of appropriate
495	* size is allocated by the library. Otherwise,
496	* the client must guarantee that the buffer is
497	* large enough to hold any individual strip of
498	* raw data.
499	*/
500	int
501	TIFFReadBufferSetup(TIFF* tif, tdata_t bp, tsize_t size)
502	{
503	static const char module[] = "TIFFReadBufferSetup";
504
505	if (tif->tif_rawdata) {
506	if (tif->tif_flags & TIFF_MYBUFFER)
507	_TIFFfree(tif->tif_rawdata);
508	tif->tif_rawdata = NULL;
509	}
510	if (bp) {
511	tif->tif_rawdatasize = size;
512	tif->tif_rawdata = (tidata_t) bp;
513	tif->tif_flags &= ~TIFF_MYBUFFER;
514	} else {
515	tif->tif_rawdatasize = TIFFroundup(size, 1024);
516	tif->tif_rawdata = (tidata_t) _TIFFmalloc(tif->tif_rawdatasize);
517	tif->tif_flags \|= TIFF_MYBUFFER;
518	}
519	if (tif->tif_rawdata == NULL) {
520	TIFFError(module,
521	"%s: No space for data buffer at scanline %ld",
522	tif->tif_name, (long) tif->tif_row);
523	tif->tif_rawdatasize = 0;
524	return (0);
525	}
526	return (1);
527	}
528
529	/*
530	* Set state to appear as if a
531	* strip has just been read in.
532	*/
533	static int
534	TIFFStartStrip(TIFF* tif, tstrip_t strip)
535	{
536	TIFFDirectory *td = &tif->tif_dir;
537
538	if ((tif->tif_flags & TIFF_CODERSETUP) == 0) {
539	if (!(*tif->tif_setupdecode)(tif))
540	return (0);
541	tif->tif_flags \|= TIFF_CODERSETUP;
542	}
543	tif->tif_curstrip = strip;
544	tif->tif_row = (strip % td->td_stripsperimage) * td->td_rowsperstrip;
545	tif->tif_rawcp = tif->tif_rawdata;
546	tif->tif_rawcc = td->td_stripbytecount[strip];
547	return ((*tif->tif_predecode)(tif,
548	(tsample_t)(strip / td->td_stripsperimage)));
549	}
550
551	/*
552	* Set state to appear as if a
553	* tile has just been read in.
554	*/
555	static int
556	TIFFStartTile(TIFF* tif, ttile_t tile)
557	{
558	TIFFDirectory *td = &tif->tif_dir;
559
560	if ((tif->tif_flags & TIFF_CODERSETUP) == 0) {
561	if (!(*tif->tif_setupdecode)(tif))
562	return (0);
563	tif->tif_flags \|= TIFF_CODERSETUP;
564	}
565	tif->tif_curtile = tile;
566	tif->tif_row =
567	(tile % TIFFhowmany(td->td_imagewidth, td->td_tilewidth)) *
568	td->td_tilelength;
569	tif->tif_col =
570	(tile % TIFFhowmany(td->td_imagelength, td->td_tilelength)) *
571	td->td_tilewidth;
572	tif->tif_rawcp = tif->tif_rawdata;
573	tif->tif_rawcc = td->td_stripbytecount[tile];
574	return ((*tif->tif_predecode)(tif,
575	(tsample_t)(tile/td->td_stripsperimage)));
576	}
577
578	static int
579	TIFFCheckRead(TIFF* tif, int tiles)
580	{
581	if (tif->tif_mode == O_WRONLY) {
582	TIFFError(tif->tif_name, "File not open for reading");
583	return (0);
584	}
585	if (tiles ^ isTiled(tif)) {
586	TIFFError(tif->tif_name, tiles ?
587	"Can not read tiles from a stripped image" :
588	"Can not read scanlines from a tiled image");
589	return (0);
590	}
591	return (1);
592	}
593
594	void
595	_TIFFNoPostDecode(TIFF* tif, tidata_t buf, tsize_t cc)
596	{
597	(void) tif; (void) buf; (void) cc;
598	}
599
600	void
601	_TIFFSwab16BitData(TIFF* tif, tidata_t buf, tsize_t cc)
602	{
603	(void) tif;
604	assert((cc & 1) == 0);
605	TIFFSwabArrayOfShort((uint16*) buf, cc/2);
606	}
607
608	void
609	_TIFFSwab32BitData(TIFF* tif, tidata_t buf, tsize_t cc)
610	{
611	(void) tif;
612	assert((cc & 3) == 0);
613	TIFFSwabArrayOfLong((uint32*) buf, cc/4);
614	}
615
616	void
617	_TIFFSwab64BitData(TIFF* tif, tidata_t buf, tsize_t cc)
618	{
619	(void) tif;
620	assert((cc & 7) == 0);
621	TIFFSwabArrayOfDouble((double*) buf, cc/8);
622	}