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/* $Id: tif_read.c,v 1.40 2012-06-01 00:55:09 fwarmerdam 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.
 * Scanline-oriented Read Support
 */
#include "tiffiop.h"
#include <stdio.h>

int TIFFFillStrip(TIFF* tif, uint32 strip);
int TIFFFillTile(TIFF* tif, uint32 tile);
static int TIFFStartStrip(TIFF* tif, uint32 strip);
static int TIFFStartTile(TIFF* tif, uint32 tile);
static int TIFFCheckRead(TIFF*, int);
static tmsize_t
TIFFReadRawStrip1(TIFF* tif, uint32 strip, void* buf, tmsize_t size,const char* module);

#define NOSTRIP ((uint32)(-1))       /* undefined state */
#define NOTILE ((uint32)(-1))         /* undefined state */

static int
TIFFFillStripPartial( TIFF *tif, int strip, tmsize_t read_ahead, int restart )
{
    static const char module[] = "TIFFFillStripPartial";
    register TIFFDirectory *td = &tif->tif_dir;
        uint64 unused_data;
        uint64 read_offset;
        tmsize_t cc, to_read;
        tmsize_t bytecountm;

        if (!_TIFFFillStriles( tif ) || !tif->tif_dir.td_stripbytecount)
            return 0;

        /*
         * 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?).
         */

        bytecountm=(tmsize_t) td->td_stripbytecount[strip];
        if (read_ahead*2 > tif->tif_rawdatasize) {
                assert( restart );

                tif->tif_curstrip = NOSTRIP;
                if ((tif->tif_flags & TIFF_MYBUFFER) == 0) {
                        TIFFErrorExt(tif->tif_clientdata, module,
                                     "Data buffer too small to hold part of strip %lu",
                                     (unsigned long) strip);
                        return (0);
                }
                if (!TIFFReadBufferSetup(tif, 0, read_ahead*2))
                        return (0);
        }

        if( restart )
        {
                tif->tif_rawdataloaded = 0;
                tif->tif_rawdataoff = 0;
        }

        /*
        ** If we are reading more data, move any unused data to the
        ** start of the buffer.
        */
        if( tif->tif_rawdataloaded > 0 )
                unused_data = tif->tif_rawdataloaded - (tif->tif_rawcp - tif->tif_rawdata);
        else
                unused_data = 0;

        if( unused_data > 0 )
        {
        assert((tif->tif_flags&TIFF_BUFFERMMAP)==0);
                memmove( tif->tif_rawdata, tif->tif_rawcp, unused_data );
        }

        /*
        ** Seek to the point in the file where more data should be read.
        */
        read_offset = td->td_stripoffset[strip]
                + tif->tif_rawdataoff + tif->tif_rawdataloaded;

        if (!SeekOK(tif, read_offset)) {
                TIFFErrorExt(tif->tif_clientdata, module,
                             "Seek error at scanline %lu, strip %lu",
                             (unsigned long) tif->tif_row, (unsigned long) strip);
                return 0;
        }

        /*
        ** How much do we want to read?
        */
        to_read = tif->tif_rawdatasize - unused_data;
        if( (uint64) to_read > td->td_stripbytecount[strip]
            - tif->tif_rawdataoff - tif->tif_rawdataloaded )
        {
                to_read = td->td_stripbytecount[strip]
                        - tif->tif_rawdataoff - tif->tif_rawdataloaded;
        }

    assert((tif->tif_flags&TIFF_BUFFERMMAP)==0);
        cc = TIFFReadFile(tif, tif->tif_rawdata + unused_data, to_read);

        if (cc != to_read) {
#if defined(__WIN32__) && (defined(_MSC_VER) || defined(__MINGW32__))
                TIFFErrorExt(tif->tif_clientdata, module,
                             "Read error at scanline %lu; got %I64u bytes, expected %I64u",
                             (unsigned long) tif->tif_row,
                             (unsigned __int64) cc,
                             (unsigned __int64) to_read);
#else
                TIFFErrorExt(tif->tif_clientdata, module,
                             "Read error at scanline %lu; got %llu bytes, expected %llu",
                             (unsigned long) tif->tif_row,
                             (unsigned long long) cc,
                             (unsigned long long) to_read);
#endif
                return 0;
        }

        tif->tif_rawdataoff = tif->tif_rawdataoff + tif->tif_rawdataloaded - unused_data ;
        tif->tif_rawdataloaded = unused_data + to_read;

        tif->tif_rawcp = tif->tif_rawdata;

        if (!isFillOrder(tif, td->td_fillorder) &&
            (tif->tif_flags & TIFF_NOBITREV) == 0) {
        assert((tif->tif_flags&TIFF_BUFFERMMAP)==0);
                TIFFReverseBits(tif->tif_rawdata + unused_data, to_read );
    }

        /*
        ** When starting a strip from the beginning we need to
        ** restart the decoder.
        */
        if( restart )
                return TIFFStartStrip(tif, strip);
        else
                return 1;
}

/*
 * Seek to a random row+sample in a file.
 *
 * Only used by TIFFReadScanline, and is only used on
 * strip organized files.  We do some tricky stuff to try
 * and avoid reading the whole compressed raw data for big
 * strips.
 */
static int
TIFFSeek(TIFF* tif, uint32 row, uint16 sample )
{
    register TIFFDirectory *td = &tif->tif_dir;
    uint32 strip;
        int    whole_strip;
    tmsize_t read_ahead = 0;

        /*
        ** Establish what strip we are working from.
        */
    if (row >= td->td_imagelength) {	/* out of range */
        TIFFErrorExt(tif->tif_clientdata, tif->tif_name,
            "%lu: Row out of range, max %lu",
            (unsigned long) row,
            (unsigned long) td->td_imagelength);
        return (0);
    }
    if (td->td_planarconfig == PLANARCONFIG_SEPARATE) {
        if (sample >= td->td_samplesperpixel) {
            TIFFErrorExt(tif->tif_clientdata, tif->tif_name,
                "%lu: Sample out of range, max %lu",
                (unsigned long) sample, (unsigned long) td->td_samplesperpixel);
            return (0);
        }
        strip = (uint32)sample*td->td_stripsperimage + row/td->td_rowsperstrip;
    } else
        strip = row / td->td_rowsperstrip;

        /*
         * Do we want to treat this strip as one whole chunk or
         * read it a few lines at a time?
         */
#if defined(CHUNKY_STRIP_READ_SUPPORT)
        if (!_TIFFFillStriles( tif ) || !tif->tif_dir.td_stripbytecount)
            return 0;
        whole_strip = tif->tif_dir.td_stripbytecount[strip] < 10
                || isMapped(tif);
#else
        whole_strip = 1;
#endif

        if( !whole_strip )
        {
                read_ahead = tif->tif_scanlinesize * 16 + 5000;
        }

        /*
         * If we haven't loaded this strip, do so now, possibly
         * only reading the first part.
         */
    if (strip != tif->tif_curstrip) {	/* different strip, refill */

                if( whole_strip )
                {
                        if (!TIFFFillStrip(tif, strip))
                                return (0);
                }
                else
                {
                        if( !TIFFFillStripPartial(tif,strip,read_ahead,1) )
                                return 0;
                }
    }

        /*
        ** If we already have some data loaded, do we need to read some more?
        */
        else if( !whole_strip )
        {
                if( ((tif->tif_rawdata + tif->tif_rawdataloaded) - tif->tif_rawcp) < read_ahead
                    && (uint64) tif->tif_rawdataoff+tif->tif_rawdataloaded < td->td_stripbytecount[strip] )
                {
                        if( !TIFFFillStripPartial(tif,strip,read_ahead,0) )
                                return 0;
                }
        }

        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( tif->tif_rawdataoff != 0 )
                {
                        if( !TIFFFillStripPartial(tif,strip,read_ahead,1) )
                                return 0;
                }
                else
                {
                        if (!TIFFStartStrip(tif, strip))
                                return (0);
                }
    }

    if (row != tif->tif_row) {
        /*
         * Seek forward to the desired row.
         */

                /* TODO: Will this really work with partial buffers? */

        if (!(*tif->tif_seek)(tif, row - tif->tif_row))
            return (0);
        tif->tif_row = row;
    }

    return (1);
}

int
TIFFReadScanline(TIFF* tif, void* buf, uint32 row, uint16 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, (uint8*) buf, tif->tif_scanlinesize, sample);

        /* we are now poised at the beginning of the next row */
        tif->tif_row = row + 1;

        if (e)
            (*tif->tif_postdecode)(tif, (uint8*) buf,
                tif->tif_scanlinesize);
    }
    return (e > 0 ? 1 : -1);
}

/*
 * Read a strip of data and decompress the specified
 * amount into the user-supplied buffer.
 */
tmsize_t
TIFFReadEncodedStrip(TIFF* tif, uint32 strip, void* buf, tmsize_t size)
{
    static const char module[] = "TIFFReadEncodedStrip";
    TIFFDirectory *td = &tif->tif_dir;
    uint32 rowsperstrip;
    uint32 stripsperplane;
    uint32 stripinplane;
    uint16 plane;
    uint32 rows;
    tmsize_t stripsize;
    if (!TIFFCheckRead(tif,0))
        return((tmsize_t)(-1));
    if (strip>=td->td_nstrips)
    {
        TIFFErrorExt(tif->tif_clientdata,module,
            "%lu: Strip out of range, max %lu",(unsigned long)strip,
            (unsigned long)td->td_nstrips);
        return((tmsize_t)(-1));
    }
    /*
     * Calculate the strip size according to the number of
     * rows in the strip (check for truncated last strip on any
     * of the separations).
     */
    rowsperstrip=td->td_rowsperstrip;
    if (rowsperstrip>td->td_imagelength)
        rowsperstrip=td->td_imagelength;
    stripsperplane=((td->td_imagelength+rowsperstrip-1)/rowsperstrip);
    stripinplane=(strip%stripsperplane);
    plane=(strip/stripsperplane);
    rows=td->td_imagelength-stripinplane*rowsperstrip;
    if (rows>rowsperstrip)
        rows=rowsperstrip;
    stripsize=TIFFVStripSize(tif,rows);
    if (stripsize==0)
        return((tmsize_t)(-1));
    if ((size!=(tmsize_t)(-1))&&(size<stripsize))
        stripsize=size;
    if (!TIFFFillStrip(tif,strip))
        return((tmsize_t)(-1));
    if ((*tif->tif_decodestrip)(tif,buf,stripsize,plane)<=0)
        return((tmsize_t)(-1));
    (*tif->tif_postdecode)(tif,buf,stripsize);
    return(stripsize);
}

static tmsize_t
TIFFReadRawStrip1(TIFF* tif, uint32 strip, void* buf, tmsize_t size,
    const char* module)
{
    TIFFDirectory *td = &tif->tif_dir;

    if (!_TIFFFillStriles( tif ))
        return ((tmsize_t)(-1));

    assert((tif->tif_flags&TIFF_NOREADRAW)==0);
    if (!isMapped(tif)) {
        tmsize_t cc;

        if (!SeekOK(tif, td->td_stripoffset[strip])) {
            TIFFErrorExt(tif->tif_clientdata, module,
                "Seek error at scanline %lu, strip %lu",
                (unsigned long) tif->tif_row, (unsigned long) strip);
            return ((tmsize_t)(-1));
        }
        cc = TIFFReadFile(tif, buf, size);
        if (cc != size) {
#if defined(__WIN32__) && (defined(_MSC_VER) || defined(__MINGW32__))
            TIFFErrorExt(tif->tif_clientdata, module,
        "Read error at scanline %lu; got %I64u bytes, expected %I64u",
                     (unsigned long) tif->tif_row,
                     (unsigned __int64) cc,
                     (unsigned __int64) size);
#else
            TIFFErrorExt(tif->tif_clientdata, module,
        "Read error at scanline %lu; got %llu bytes, expected %llu",
                     (unsigned long) tif->tif_row,
                     (unsigned long long) cc,
                     (unsigned long long) size);
#endif
            return ((tmsize_t)(-1));
        }
    } else {
        tmsize_t ma,mb;
        tmsize_t n;
        ma=(tmsize_t)td->td_stripoffset[strip];
        mb=ma+size;
        if (((uint64)ma!=td->td_stripoffset[strip])||(ma>tif->tif_size))
            n=0;
        else if ((mb<ma)||(mb<size)||(mb>tif->tif_size))
            n=tif->tif_size-ma;
        else
            n=size;
        if (n!=size) {
#if defined(__WIN32__) && (defined(_MSC_VER) || defined(__MINGW32__))
            TIFFErrorExt(tif->tif_clientdata, module,
    "Read error at scanline %lu, strip %lu; got %I64u bytes, expected %I64u",
                     (unsigned long) tif->tif_row,
                     (unsigned long) strip,
                     (unsigned __int64) n,
                     (unsigned __int64) size);
#else
            TIFFErrorExt(tif->tif_clientdata, module,
    "Read error at scanline %lu, strip %lu; got %llu bytes, expected %llu",
                     (unsigned long) tif->tif_row,
                     (unsigned long) strip,
                     (unsigned long long) n,
                     (unsigned long long) size);
#endif
            return ((tmsize_t)(-1));
        }
        _TIFFmemcpy(buf, tif->tif_base + ma,
                size);
    }
    return (size);
}

/*
 * Read a strip of data from the file.
 */
tmsize_t
TIFFReadRawStrip(TIFF* tif, uint32 strip, void* buf, tmsize_t size)
{
    static const char module[] = "TIFFReadRawStrip";
    TIFFDirectory *td = &tif->tif_dir;
    uint64 bytecount;
    tmsize_t bytecountm;

    if (!TIFFCheckRead(tif, 0))
        return ((tmsize_t)(-1));
    if (strip >= td->td_nstrips) {
        TIFFErrorExt(tif->tif_clientdata, module,
             "%lu: Strip out of range, max %lu",
             (unsigned long) strip,
             (unsigned long) td->td_nstrips);
        return ((tmsize_t)(-1));
    }
    if (tif->tif_flags&TIFF_NOREADRAW)
    {
        TIFFErrorExt(tif->tif_clientdata, module,
            "Compression scheme does not support access to raw uncompressed data");
        return ((tmsize_t)(-1));
    }
    bytecount = td->td_stripbytecount[strip];
    if (bytecount <= 0) {
#if defined(__WIN32__) && (defined(_MSC_VER) || defined(__MINGW32__))
        TIFFErrorExt(tif->tif_clientdata, module,
                 "%I64u: Invalid strip byte count, strip %lu",
                 (unsigned __int64) bytecount,
                 (unsigned long) strip);
#else
        TIFFErrorExt(tif->tif_clientdata, module,
                 "%llu: Invalid strip byte count, strip %lu",
                 (unsigned long long) bytecount,
                 (unsigned long) strip);
#endif
        return ((tmsize_t)(-1));
    }
    bytecountm = (tmsize_t)bytecount;
    if ((uint64)bytecountm!=bytecount) {
        TIFFErrorExt(tif->tif_clientdata, module, "Integer overflow");
        return ((tmsize_t)(-1));
    }
    if (size != (tmsize_t)(-1) && size < bytecountm)
        bytecountm = size;
    return (TIFFReadRawStrip1(tif, strip, buf, bytecountm, module));
}

/*
 * Read the specified strip and setup for decoding. The data buffer is
 * expanded, as necessary, to hold the strip's data.
 */
int
TIFFFillStrip(TIFF* tif, uint32 strip)
{
    static const char module[] = "TIFFFillStrip";
    TIFFDirectory *td = &tif->tif_dir;

    if (!_TIFFFillStriles( tif ) || !tif->tif_dir.td_stripbytecount)
        return 0;

    if ((tif->tif_flags&TIFF_NOREADRAW)==0)
    {
        uint64 bytecount = td->td_stripbytecount[strip];
        if (bytecount <= 0) {
#if defined(__WIN32__) && (defined(_MSC_VER) || defined(__MINGW32__))
            TIFFErrorExt(tif->tif_clientdata, module,
                "Invalid strip byte count %I64u, strip %lu",
                     (unsigned __int64) bytecount,
                     (unsigned long) strip);
#else
            TIFFErrorExt(tif->tif_clientdata, module,
                "Invalid strip byte count %llu, strip %lu",
                     (unsigned long long) bytecount,
                     (unsigned long) strip);
#endif
            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_rawdata = NULL;
                tif->tif_rawdatasize = 0;
            }
            tif->tif_flags &= ~TIFF_MYBUFFER;
            /*
             * We must check for overflow, potentially causing
             * an OOB read. Instead of simple
             *
             *  td->td_stripoffset[strip]+bytecount > tif->tif_size
             *
             * comparison (which can overflow) we do the following
             * two comparisons:
             */
            if (bytecount > (uint64)tif->tif_size ||
                td->td_stripoffset[strip] > (uint64)tif->tif_size - bytecount) {
                /*
                 * This error message might seem strange, but
                 * it's what would happen if a read were done
                 * instead.
                 */
#if defined(__WIN32__) && (defined(_MSC_VER) || defined(__MINGW32__))
                TIFFErrorExt(tif->tif_clientdata, module,

                    "Read error on strip %lu; "
                    "got %I64u bytes, expected %I64u",
                    (unsigned long) strip,
                    (unsigned __int64) tif->tif_size - td->td_stripoffset[strip],
                    (unsigned __int64) bytecount);
#else
                TIFFErrorExt(tif->tif_clientdata, module,

                    "Read error on strip %lu; "
                    "got %llu bytes, expected %llu",
                    (unsigned long) strip,
                    (unsigned long long) tif->tif_size - td->td_stripoffset[strip],
                    (unsigned long long) bytecount);
#endif
                tif->tif_curstrip = NOSTRIP;
                return (0);
            }
            tif->tif_rawdatasize = (tmsize_t)bytecount;
            tif->tif_rawdata = tif->tif_base + (tmsize_t)td->td_stripoffset[strip];
                        tif->tif_rawdataoff = 0;
                        tif->tif_rawdataloaded = (tmsize_t) bytecount;

            /*
             * When we have tif_rawdata reference directly into the memory mapped file
             * we need to be pretty careful about how we use the rawdata.  It is not
             * a general purpose working buffer as it normally otherwise is.  So we
             * keep track of this fact to avoid using it improperly.
             */
            tif->tif_flags |= TIFF_BUFFERMMAP;
        } 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?).
             */
            tmsize_t bytecountm;
            bytecountm=(tmsize_t)bytecount;
            if ((uint64)bytecountm!=bytecount)
            {
                TIFFErrorExt(tif->tif_clientdata,module,"Integer overflow");
                return(0);
            }
            if (bytecountm > tif->tif_rawdatasize) {
                tif->tif_curstrip = NOSTRIP;
                if ((tif->tif_flags & TIFF_MYBUFFER) == 0) {
                    TIFFErrorExt(tif->tif_clientdata, module,
                        "Data buffer too small to hold strip %lu",
                        (unsigned long) strip);
                    return (0);
                }
                if (!TIFFReadBufferSetup(tif, 0, bytecountm))
                    return (0);
            }
            if (tif->tif_flags&TIFF_BUFFERMMAP) {
                tif->tif_curstrip = NOSTRIP;
                if (!TIFFReadBufferSetup(tif, 0, bytecountm))
                    return (0);
            }
            if (TIFFReadRawStrip1(tif, strip, tif->tif_rawdata,
                bytecountm, module) != bytecountm)
                return (0);

                        tif->tif_rawdataoff = 0;
                        tif->tif_rawdataloaded = bytecountm;

            if (!isFillOrder(tif, td->td_fillorder) &&
                (tif->tif_flags & TIFF_NOBITREV) == 0)
                TIFFReverseBits(tif->tif_rawdata, bytecountm);
                }
    }
    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.
 */
tmsize_t
TIFFReadTile(TIFF* tif, void* buf, uint32 x, uint32 y, uint32 z, uint16 s)
{
    if (!TIFFCheckRead(tif, 1) || !TIFFCheckTile(tif, x, y, z, s))
        return ((tmsize_t)(-1));
    return (TIFFReadEncodedTile(tif,
        TIFFComputeTile(tif, x, y, z, s), buf, (tmsize_t)(-1)));
}

/*
 * Read a tile of data and decompress the specified
 * amount into the user-supplied buffer.
 */
tmsize_t
TIFFReadEncodedTile(TIFF* tif, uint32 tile, void* buf, tmsize_t size)
{
    static const char module[] = "TIFFReadEncodedTile";
    TIFFDirectory *td = &tif->tif_dir;
    tmsize_t tilesize = tif->tif_tilesize;

    if (!TIFFCheckRead(tif, 1))
        return ((tmsize_t)(-1));
    if (tile >= td->td_nstrips) {
        TIFFErrorExt(tif->tif_clientdata, module,
            "%lu: Tile out of range, max %lu",
            (unsigned long) tile, (unsigned long) td->td_nstrips);
        return ((tmsize_t)(-1));
    }
    if (size == (tmsize_t)(-1))
        size = tilesize;
    else if (size > tilesize)
        size = tilesize;
    if (TIFFFillTile(tif, tile) && (*tif->tif_decodetile)(tif,
        (uint8*) buf, size, (uint16)(tile/td->td_stripsperimage))) {
        (*tif->tif_postdecode)(tif, (uint8*) buf, size);
        return (size);
    } else
        return ((tmsize_t)(-1));
}

static tmsize_t
TIFFReadRawTile1(TIFF* tif, uint32 tile, void* buf, tmsize_t size, const char* module)
{
    TIFFDirectory *td = &tif->tif_dir;

    if (!_TIFFFillStriles( tif ))
        return ((tmsize_t)(-1));

    assert((tif->tif_flags&TIFF_NOREADRAW)==0);
    if (!isMapped(tif)) {
        tmsize_t cc;

        if (!SeekOK(tif, td->td_stripoffset[tile])) {
            TIFFErrorExt(tif->tif_clientdata, module,
                "Seek error at row %lu, col %lu, tile %lu",
                (unsigned long) tif->tif_row,
                (unsigned long) tif->tif_col,
                (unsigned long) tile);
            return ((tmsize_t)(-1));
        }
        cc = TIFFReadFile(tif, buf, size);
        if (cc != size) {
#if defined(__WIN32__) && (defined(_MSC_VER) || defined(__MINGW32__))
            TIFFErrorExt(tif->tif_clientdata, module,
    "Read error at row %lu, col %lu; got %I64u bytes, expected %I64u",
                     (unsigned long) tif->tif_row,
                     (unsigned long) tif->tif_col,
                     (unsigned __int64) cc,
                     (unsigned __int64) size);
#else
            TIFFErrorExt(tif->tif_clientdata, module,
    "Read error at row %lu, col %lu; got %llu bytes, expected %llu",
                     (unsigned long) tif->tif_row,
                     (unsigned long) tif->tif_col,
                     (unsigned long long) cc,
                     (unsigned long long) size);
#endif
            return ((tmsize_t)(-1));
        }
    } else {
        tmsize_t ma,mb;
        tmsize_t n;
        ma=(tmsize_t)td->td_stripoffset[tile];
        mb=ma+size;
        if (((uint64)ma!=td->td_stripoffset[tile])||(ma>tif->tif_size))
            n=0;
        else if ((mb<ma)||(mb<size)||(mb>tif->tif_size))
            n=tif->tif_size-ma;
        else
            n=size;
        if (n!=size) {
#if defined(__WIN32__) && (defined(_MSC_VER) || defined(__MINGW32__))
            TIFFErrorExt(tif->tif_clientdata, module,
"Read error at row %lu, col %lu, tile %lu; got %I64u bytes, expected %I64u",
                     (unsigned long) tif->tif_row,
                     (unsigned long) tif->tif_col,
                     (unsigned long) tile,
                     (unsigned __int64) n,
                     (unsigned __int64) size);
#else
            TIFFErrorExt(tif->tif_clientdata, module,
"Read error at row %lu, col %lu, tile %lu; got %llu bytes, expected %llu",
                     (unsigned long) tif->tif_row,
                     (unsigned long) tif->tif_col,
                     (unsigned long) tile,
                     (unsigned long long) n,
                     (unsigned long long) size);
#endif
            return ((tmsize_t)(-1));
        }
        _TIFFmemcpy(buf, tif->tif_base + ma, size);
    }
    return (size);
}

/*
 * Read a tile of data from the file.
 */
tmsize_t
TIFFReadRawTile(TIFF* tif, uint32 tile, void* buf, tmsize_t size)
{
    static const char module[] = "TIFFReadRawTile";
    TIFFDirectory *td = &tif->tif_dir;
    uint64 bytecount64;
    tmsize_t bytecountm;

    if (!TIFFCheckRead(tif, 1))
        return ((tmsize_t)(-1));
    if (tile >= td->td_nstrips) {
        TIFFErrorExt(tif->tif_clientdata, module,
            "%lu: Tile out of range, max %lu",
            (unsigned long) tile, (unsigned long) td->td_nstrips);
        return ((tmsize_t)(-1));
    }
    if (tif->tif_flags&TIFF_NOREADRAW)
    {
        TIFFErrorExt(tif->tif_clientdata, module,
        "Compression scheme does not support access to raw uncompressed data");
        return ((tmsize_t)(-1));
    }
    bytecount64 = td->td_stripbytecount[tile];
    if (size != (tmsize_t)(-1) && (uint64)size < bytecount64)
        bytecount64 = (uint64)size;
    bytecountm = (tmsize_t)bytecount64;
    if ((uint64)bytecountm!=bytecount64)
    {
        TIFFErrorExt(tif->tif_clientdata,module,"Integer overflow");
        return ((tmsize_t)(-1));
    }
    return (TIFFReadRawTile1(tif, tile, buf, bytecountm, module));
}

/*
 * Read the specified tile and setup for decoding. The data buffer is
 * expanded, as necessary, to hold the tile's data.
 */
int
TIFFFillTile(TIFF* tif, uint32 tile)
{
    static const char module[] = "TIFFFillTile";
    TIFFDirectory *td = &tif->tif_dir;

    if (!_TIFFFillStriles( tif ) || !tif->tif_dir.td_stripbytecount)
        return 0;

    if ((tif->tif_flags&TIFF_NOREADRAW)==0)
    {
        uint64 bytecount = td->td_stripbytecount[tile];
        if (bytecount <= 0) {
#if defined(__WIN32__) && (defined(_MSC_VER) || defined(__MINGW32__))
            TIFFErrorExt(tif->tif_clientdata, module,
                "%I64u: Invalid tile byte count, tile %lu",
                     (unsigned __int64) bytecount,
                     (unsigned long) tile);
#else
            TIFFErrorExt(tif->tif_clientdata, module,
                "%llu: Invalid tile byte count, tile %lu",
                     (unsigned long long) bytecount,
                     (unsigned long) tile);
#endif
            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_rawdata = NULL;
                tif->tif_rawdatasize = 0;
            }
            tif->tif_flags &= ~TIFF_MYBUFFER;
            /*
             * We must check for overflow, potentially causing
             * an OOB read. Instead of simple
             *
             *  td->td_stripoffset[tile]+bytecount > tif->tif_size
             *
             * comparison (which can overflow) we do the following
             * two comparisons:
             */
            if (bytecount > (uint64)tif->tif_size ||
                td->td_stripoffset[tile] > (uint64)tif->tif_size - bytecount) {
                tif->tif_curtile = NOTILE;
                return (0);
            }
            tif->tif_rawdatasize = (tmsize_t)bytecount;
            tif->tif_rawdata =
                tif->tif_base + (tmsize_t)td->td_stripoffset[tile];
                        tif->tif_rawdataoff = 0;
                        tif->tif_rawdataloaded = (tmsize_t) bytecount;
            tif->tif_flags |= TIFF_BUFFERMMAP;
        } 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?).
             */
            tmsize_t bytecountm;
            bytecountm=(tmsize_t)bytecount;
            if ((uint64)bytecountm!=bytecount)
            {
                TIFFErrorExt(tif->tif_clientdata,module,"Integer overflow");
                return(0);
            }
            if (bytecountm > tif->tif_rawdatasize) {
                tif->tif_curtile = NOTILE;
                if ((tif->tif_flags & TIFF_MYBUFFER) == 0) {
                    TIFFErrorExt(tif->tif_clientdata, module,
                        "Data buffer too small to hold tile %lu",
                        (unsigned long) tile);
                    return (0);
                }
                if (!TIFFReadBufferSetup(tif, 0, bytecountm))
                    return (0);
            }
            if (tif->tif_flags&TIFF_BUFFERMMAP) {
                tif->tif_curtile = NOTILE;
                if (!TIFFReadBufferSetup(tif, 0, bytecountm))
                    return (0);
            }

            if (TIFFReadRawTile1(tif, tile, tif->tif_rawdata,
                bytecountm, module) != bytecountm)
                return (0);

                        tif->tif_rawdataoff = 0;
                        tif->tif_rawdataloaded = bytecountm;

            if (!isFillOrder(tif, td->td_fillorder) &&
                (tif->tif_flags & TIFF_NOBITREV) == 0)
                TIFFReverseBits(tif->tif_rawdata,
                                                tif->tif_rawdataloaded);
        }
    }
    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, void* bp, tmsize_t size)
{
    static const char module[] = "TIFFReadBufferSetup";

    assert((tif->tif_flags&TIFF_NOREADRAW)==0);
    tif->tif_flags &= ~TIFF_BUFFERMMAP;

    if (tif->tif_rawdata) {
        if (tif->tif_flags & TIFF_MYBUFFER)
            _TIFFfree(tif->tif_rawdata);
        tif->tif_rawdata = NULL;
        tif->tif_rawdatasize = 0;
    }
    if (bp) {
        tif->tif_rawdatasize = size;
        tif->tif_rawdata = (uint8*) bp;
        tif->tif_flags &= ~TIFF_MYBUFFER;
    } else {
        tif->tif_rawdatasize = (tmsize_t)TIFFroundup_64((uint64)size, 1024);
        if (tif->tif_rawdatasize==0)
            tif->tif_rawdatasize=(tmsize_t)(-1);
        tif->tif_rawdata = (uint8*) _TIFFmalloc(tif->tif_rawdatasize);
        tif->tif_flags |= TIFF_MYBUFFER;
    }
    if (tif->tif_rawdata == NULL) {
        TIFFErrorExt(tif->tif_clientdata, module,
            "No space for data buffer at scanline %lu",
            (unsigned 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, uint32 strip)
{
    TIFFDirectory *td = &tif->tif_dir;

    if (!_TIFFFillStriles( tif ) || !tif->tif_dir.td_stripbytecount)
        return 0;

    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_flags &= ~TIFF_BUF4WRITE;

    if (tif->tif_flags&TIFF_NOREADRAW)
    {
        tif->tif_rawcp = NULL;
        tif->tif_rawcc = 0;
    }
    else
    {
        tif->tif_rawcp = tif->tif_rawdata;
        tif->tif_rawcc = (tmsize_t)td->td_stripbytecount[strip];
    }
    return ((*tif->tif_predecode)(tif,
            (uint16)(strip / td->td_stripsperimage)));
}

/*
 * Set state to appear as if a
 * tile has just been read in.
 */
static int
TIFFStartTile(TIFF* tif, uint32 tile)
{
    TIFFDirectory *td = &tif->tif_dir;

    if (!_TIFFFillStriles( tif ) || !tif->tif_dir.td_stripbytecount)
        return 0;

    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_32(td->td_imagewidth, td->td_tilewidth)) *
        td->td_tilelength;
    tif->tif_col =
        (tile % TIFFhowmany_32(td->td_imagelength, td->td_tilelength)) *
        td->td_tilewidth;
        tif->tif_flags &= ~TIFF_BUF4WRITE;
    if (tif->tif_flags&TIFF_NOREADRAW)
    {
        tif->tif_rawcp = NULL;
        tif->tif_rawcc = 0;
    }
    else
    {
        tif->tif_rawcp = tif->tif_rawdata;
        tif->tif_rawcc = (tmsize_t)td->td_stripbytecount[tile];
    }
    return ((*tif->tif_predecode)(tif,
            (uint16)(tile/td->td_stripsperimage)));
}

static int
TIFFCheckRead(TIFF* tif, int tiles)
{
    if (tif->tif_mode == O_WRONLY) {
        TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "File not open for reading");
        return (0);
    }
    if (tiles ^ isTiled(tif)) {
        TIFFErrorExt(tif->tif_clientdata, 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, uint8* buf, tmsize_t cc)
{
    (void) tif; (void) buf; (void) cc;
}

void
_TIFFSwab16BitData(TIFF* tif, uint8* buf, tmsize_t cc)
{
    (void) tif;
    assert((cc & 1) == 0);
    TIFFSwabArrayOfShort((uint16*) buf, cc/2);
}

void
_TIFFSwab24BitData(TIFF* tif, uint8* buf, tmsize_t cc)
{
    (void) tif;
    assert((cc % 3) == 0);
    TIFFSwabArrayOfTriples((uint8*) buf, cc/3);
}

void
_TIFFSwab32BitData(TIFF* tif, uint8* buf, tmsize_t cc)
{
    (void) tif;
    assert((cc & 3) == 0);
    TIFFSwabArrayOfLong((uint32*) buf, cc/4);
}

void
_TIFFSwab64BitData(TIFF* tif, uint8* buf, tmsize_t cc)
{
    (void) tif;
    assert((cc & 7) == 0);
    TIFFSwabArrayOfDouble((double*) buf, cc/8);
}

/* vim: set ts=8 sts=8 sw=8 noet: */
/*
 * Local Variables:
 * mode: c
 * c-basic-offset: 8
 * fill-column: 78
 * End:
 */