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
	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	}