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- #ifndef lint
- static char rcsid[] = "$Header: /usr/people/sam/tiff/libtiff/RCS/tif_read.c,v 1.43 92/02/10 19:06:41 sam Exp $";
- #endif
-
- /*
- * Copyright (c) 1988, 1989, 1990, 1991, 1992 Sam Leffler
- * Copyright (c) 1991, 1992 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"
-
- #if USE_PROTOTYPES
- static TIFFSeek(TIFF *, u_int, u_int);
- static int TIFFReadRawStrip1(TIFF *, u_int, u_char *, u_int, char []);
- static int TIFFReadRawTile1(TIFF *, u_int, u_char *, u_int, char []);
- static TIFFFillStrip(TIFF *, u_int);
- static TIFFFillTile(TIFF *, u_int);
- static TIFFStartStrip(TIFF *, u_int);
- static TIFFStartTile(TIFF *, u_int);
- static TIFFCheckRead(TIFF *, int);
- #else
- static TIFFSeek();
- static int TIFFReadRawStrip1();
- static int TIFFReadRawTile1();
- static TIFFFillStrip();
- static TIFFFillTile();
- static TIFFStartStrip();
- static TIFFStartTile();
- static TIFFCheckRead();
- #endif
-
- /*VARARGS3*/
- TIFFReadScanline(tif, buf, row, sample)
- register TIFF *tif;
- u_char *buf;
- u_int row, sample;
- {
- int e;
-
- if (!TIFFCheckRead(tif, 0))
- return (-1);
- if (e = TIFFSeek(tif, row, sample)) {
- /*
- * Decompress desired row into user buffer.
- */
- e = (*tif->tif_decoderow)(tif, buf, tif->tif_scanlinesize, sample);
- tif->tif_row++;
- }
- return (e ? 1 : -1);
- }
-
- /*
- * Seek to a random row+sample in a file.
- */
- static
- /*VARARGS2*/
- TIFFSeek(tif, row, sample)
- register TIFF *tif;
- u_int row, sample;
- {
- register TIFFDirectory *td = &tif->tif_dir;
- int strip;
-
- if (row >= td->td_imagelength) { /* out of range */
- TIFFError(tif->tif_name, "%d: Row out of range, max %d",
- row, td->td_imagelength);
- return (0);
- }
- if (td->td_planarconfig == PLANARCONFIG_SEPARATE) {
- if (sample >= td->td_samplesperpixel) {
- TIFFError(tif->tif_name,
- "%d: Sample out of range, max %d",
- sample, 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) {
- if (tif->tif_seek) {
- /*
- * Seek forward to the desired row.
- */
- if (!(*tif->tif_seek)(tif, row - tif->tif_row))
- return (0);
- tif->tif_row = row;
- } else {
- TIFFError(tif->tif_name,
- "Compression algorithm does not support random access");
- return (0);
- }
- }
- return (1);
- }
-
- /*
- * Read a strip of data and decompress the specified
- * amount into the user-supplied buffer.
- */
- TIFFReadEncodedStrip(tif, strip, buf, size)
- TIFF *tif;
- u_int strip;
- u_char *buf;
- u_int size;
- {
- TIFFDirectory *td = &tif->tif_dir;
- u_int stripsize = TIFFStripSize(tif);
-
- if (!TIFFCheckRead(tif, 0))
- return (-1);
- if (strip >= td->td_nstrips) {
- TIFFError(tif->tif_name, "%d: Strip out of range, max %d",
- strip, td->td_nstrips);
- return (-1);
- }
- /*
- * Calculate the strip size according to the number of
- * rows in the strip (check for truncated last strip).
- */
- if (size == (u_int)-1)
- size = stripsize;
- else if (size > stripsize)
- size = stripsize;
- return (TIFFFillStrip(tif, strip) &&
- (*tif->tif_decodestrip)(tif, buf, size, strip / td->td_stripsperimage) ?
- size : -1);
- }
-
- /*
- * Read a strip of data from the file.
- */
- TIFFReadRawStrip(tif, strip, buf, size)
- TIFF *tif;
- u_int strip;
- u_char *buf;
- u_int size;
- {
- static char module[] = "TIFFReadRawStrip";
- TIFFDirectory *td = &tif->tif_dir;
- u_long bytecount;
-
- if (!TIFFCheckRead(tif, 0))
- return (-1);
- if (strip >= td->td_nstrips) {
- TIFFError(tif->tif_name, "%d: Strip out of range, max %d",
- strip, td->td_nstrips);
- return (-1);
- }
- bytecount = td->td_stripbytecount[strip];
- if (size != (u_int)-1 && size < bytecount)
- bytecount = size;
- return (TIFFReadRawStrip1(tif, strip, buf, bytecount, module));
- }
-
- static int
- TIFFReadRawStrip1(tif, strip, buf, size, module)
- TIFF *tif;
- u_int strip;
- u_char *buf;
- u_int size;
- char module[];
- {
- TIFFDirectory *td = &tif->tif_dir;
-
- if (!isMapped(tif)) {
- if (!SeekOK(tif->tif_fd, td->td_stripoffset[strip])) {
- TIFFError(module,
- "%s: Seek error at scanline %d, strip %d",
- tif->tif_name, tif->tif_row, strip);
- return (-1);
- }
- if (!ReadOK(tif->tif_fd, buf, size)) {
- TIFFError(module, "%s: Read error at scanline %d",
- tif->tif_name, tif->tif_row);
- return (-1);
- }
- #ifdef MMAP_SUPPORT
- } else {
- if (td->td_stripoffset[strip] + size > tif->tif_size) {
- TIFFError(module,
- "%s: Seek error at scanline %d, strip %d",
- tif->tif_name, tif->tif_row, strip);
- return (-1);
- }
- bcopy(tif->tif_base + td->td_stripoffset[strip], buf, size);
- #endif
- }
- return (size);
- }
-
- /*
- * Read the specified strip and setup for decoding.
- * The data buffer is expanded, as necessary, to
- * hold the strip's data.
- */
- static
- TIFFFillStrip(tif, strip)
- TIFF *tif;
- u_int strip;
- {
- static char module[] = "TIFFFillStrip";
- TIFFDirectory *td = &tif->tif_dir;
- u_long bytecount;
-
- bytecount = td->td_stripbytecount[strip];
- #ifdef MMAP_SUPPORT
- if (isMapped(tif) &&
- (td->td_fillorder == tif->tif_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)
- free(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 %d",
- tif->tif_name, strip);
- tif->tif_curstrip = -1; /* unknown state */
- return (0);
- }
- tif->tif_rawdatasize = bytecount;
- tif->tif_rawdata = tif->tif_base + td->td_stripoffset[strip];
- } else {
- #endif
- /*
- * 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 = -1; /* unknown state */
- if ((tif->tif_flags & TIFF_MYBUFFER) == 0) {
- TIFFError(module,
- "%s: Data buffer too small to hold strip %d",
- tif->tif_name, strip);
- return (0);
- }
- if (!TIFFReadBufferSetup(tif, 0,
- roundup(bytecount, 1024)))
- return (0);
- }
- if (TIFFReadRawStrip1(tif, strip, (u_char *)tif->tif_rawdata,
- bytecount, module) != bytecount)
- return (0);
- if (td->td_fillorder != tif->tif_fillorder &&
- (tif->tif_flags & TIFF_NOBITREV) == 0)
- TIFFReverseBits((u_char *)tif->tif_rawdata, bytecount);
- #ifdef MMAP_SUPPORT
- }
- #endif
- 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.
- */
- TIFFReadTile(tif, buf, x, y, z, s)
- TIFF *tif;
- u_char *buf;
- u_long x, y, z;
- u_int s;
- {
- u_int tile;
-
- if (!TIFFCheckRead(tif, 1) || !TIFFCheckTile(tif, x, y, z, s))
- return (-1);
- tile = TIFFComputeTile(tif, x, y, z, s);
- if (tile >= tif->tif_dir.td_nstrips) {
- TIFFError(tif->tif_name, "%d: Tile out of range, max %d",
- tile, tif->tif_dir.td_nstrips);
- return (-1);
- }
- return (TIFFFillTile(tif, tile) &&
- (*tif->tif_decodetile)(tif, buf, tif->tif_tilesize, s) ?
- tif->tif_tilesize : -1);
- }
-
- /*
- * Read a tile of data and decompress the specified
- * amount into the user-supplied buffer.
- */
- TIFFReadEncodedTile(tif, tile, buf, size)
- TIFF *tif;
- u_int tile;
- u_char *buf;
- u_int size;
- {
- TIFFDirectory *td = &tif->tif_dir;
- int tilesize = tif->tif_tilesize;
-
- if (!TIFFCheckRead(tif, 1))
- return (-1);
- if (tile >= td->td_nstrips) {
- TIFFError(tif->tif_name, "%d: Tile out of range, max %d",
- tile, td->td_nstrips);
- return (-1);
- }
- if (size == (u_int)-1)
- size = tilesize;
- else if (size > tilesize )
- size = tilesize;
- return (TIFFFillTile(tif, tile) &&
- (*tif->tif_decodetile)(tif, buf, size, tile/td->td_stripsperimage) ?
- size : -1);
- }
-
- /*
- * Read a tile of data from the file.
- */
- TIFFReadRawTile(tif, tile, buf, size)
- TIFF *tif;
- u_int tile;
- u_char *buf;
- u_int size;
- {
- static char module[] = "TIFFReadRawTile";
- TIFFDirectory *td = &tif->tif_dir;
- u_long bytecount;
-
- if (!TIFFCheckRead(tif, 1))
- return (-1);
- if (tile >= td->td_nstrips) {
- TIFFError(tif->tif_name, "%d: Tile out of range, max %d",
- tile, td->td_nstrips);
- return (-1);
- }
- bytecount = td->td_stripbytecount[tile];
- if (size != (u_int)-1 && size < bytecount)
- bytecount = size;
- return (TIFFReadRawTile1(tif, tile, buf, bytecount, module));
- }
-
- static int
- TIFFReadRawTile1(tif, tile, buf, size, module)
- TIFF *tif;
- u_int tile;
- u_char *buf;
- u_int size;
- char module[];
- {
- TIFFDirectory *td = &tif->tif_dir;
-
- if (!isMapped(tif)) {
- if (!SeekOK(tif->tif_fd, td->td_stripoffset[tile])) {
- TIFFError(module,
- "%s: Seek error at row %d, col %d, tile %d",
- tif->tif_name, tif->tif_row, tif->tif_col, tile);
- return (-1);
- }
- if (!ReadOK(tif->tif_fd, buf, size)) {
- TIFFError(module, "%s: Read error at row %d, col %d",
- tif->tif_name, tif->tif_row, tif->tif_col);
- return (-1);
- }
- #ifdef MMAP_SUPPORT
- } else {
- if (td->td_stripoffset[tile] + size > tif->tif_size) {
- TIFFError(module,
- "%s: Seek error at row %d, col %d, tile %d",
- tif->tif_name, tif->tif_row, tif->tif_col, tile);
- return (-1);
- }
- bcopy(tif->tif_base + td->td_stripoffset[tile], buf, size);
- #endif
- }
- return (size);
- }
-
- /*
- * Read the specified tile and setup for decoding.
- * The data buffer is expanded, as necessary, to
- * hold the tile's data.
- */
- static
- TIFFFillTile(tif, tile)
- TIFF *tif;
- u_int tile;
- {
- static char module[] = "TIFFFillTile";
- TIFFDirectory *td = &tif->tif_dir;
- u_long bytecount;
-
- bytecount = td->td_stripbytecount[tile];
- #ifdef MMAP_SUPPORT
- if (isMapped(tif) &&
- (td->td_fillorder == tif->tif_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)
- free(tif->tif_rawdata);
- tif->tif_flags &= ~TIFF_MYBUFFER;
- if (td->td_stripoffset[tile] + bytecount > tif->tif_size) {
- tif->tif_curtile = -1; /* unknown state */
- return (0);
- }
- tif->tif_rawdatasize = bytecount;
- tif->tif_rawdata = tif->tif_base + td->td_stripoffset[tile];
- } else {
- #endif
- /*
- * 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 = -1; /* unknown state */
- if ((tif->tif_flags & TIFF_MYBUFFER) == 0) {
- TIFFError(module,
- "%s: Data buffer too small to hold tile %d",
- tif->tif_name, tile);
- return (0);
- }
- if (!TIFFReadBufferSetup(tif, 0,
- roundup(bytecount, 1024)))
- return (0);
- }
- if (TIFFReadRawTile1(tif, tile, (u_char *)tif->tif_rawdata,
- bytecount, module) != bytecount)
- return (0);
- if (td->td_fillorder != tif->tif_fillorder &&
- (tif->tif_flags & TIFF_NOBITREV) == 0)
- TIFFReverseBits((u_char *)tif->tif_rawdata, bytecount);
- #ifdef MMAP_SUPPORT
- }
- #endif
- 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(tif, bp, size)
- TIFF *tif;
- char *bp;
- u_int size;
- {
- static char module[] = "TIFFReadBufferSetup";
-
- if (tif->tif_rawdata) {
- if (tif->tif_flags & TIFF_MYBUFFER)
- free(tif->tif_rawdata);
- tif->tif_rawdata = NULL;
- }
- if (bp) {
- tif->tif_rawdatasize = size;
- tif->tif_rawdata = bp;
- tif->tif_flags &= ~TIFF_MYBUFFER;
- } else {
- tif->tif_rawdatasize = roundup(size, 1024);
- tif->tif_rawdata = malloc(tif->tif_rawdatasize);
- tif->tif_flags |= TIFF_MYBUFFER;
- }
- if (tif->tif_rawdata == NULL) {
- TIFFError(module,
- "%s: No space for data buffer at scanline %d",
- tif->tif_name, 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
- TIFFStartStrip(tif, strip)
- register TIFF *tif;
- u_int strip;
- {
- TIFFDirectory *td = &tif->tif_dir;
-
- 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 == NULL || (*tif->tif_predecode)(tif));
- }
-
- /*
- * Set state to appear as if a
- * tile has just been read in.
- */
- static
- TIFFStartTile(tif, tile)
- register TIFF *tif;
- u_int tile;
- {
- TIFFDirectory *td = &tif->tif_dir;
-
- tif->tif_curtile = tile;
- tif->tif_row =
- (tile % howmany(td->td_imagewidth, td->td_tilewidth)) *
- td->td_tilelength;
- tif->tif_col =
- (tile % howmany(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 == NULL || (*tif->tif_predecode)(tif));
- }
-
- static
- TIFFCheckRead(tif, tiles)
- 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);
- }
-