tif_open.c

奇趣公司比较新的qt/emd版本

		 * Setup the byte order handling.
		 */
		TIFFInitOrder(tif, tif->tif_header.tiff_magic);
		/*
		 * Setup default directory.
		 */
		if (!TIFFDefaultDirectory(tif))
			goto bad;
		tif->tif_diroff = 0;
		tif->tif_dirlist = NULL;
		tif->tif_dirnumber = 0;
		return (tif);
	}
	/*
	 * Setup the byte order handling.
	 */
	if (tif->tif_header.tiff_magic != TIFF_BIGENDIAN &&
	    tif->tif_header.tiff_magic != TIFF_LITTLEENDIAN
#if MDI_SUPPORT
	    &&
#if HOST_BIGENDIAN
	    tif->tif_header.tiff_magic != MDI_BIGENDIAN
#else
	    tif->tif_header.tiff_magic != MDI_LITTLEENDIAN
#endif
	    ) {
		TIFFErrorExt(tif->tif_clientdata, name,  "Not a TIFF or MDI file, bad magic number %d (0x%x)",
#else
	    ) {
		TIFFErrorExt(tif->tif_clientdata, name,  "Not a TIFF file, bad magic number %d (0x%x)",
#endif
		    tif->tif_header.tiff_magic,
		    tif->tif_header.tiff_magic);
		goto bad;
	}
	TIFFInitOrder(tif, tif->tif_header.tiff_magic);
	/*
	 * Swap header if required.
	 */
	if (tif->tif_flags & TIFF_SWAB) {
		TIFFSwabShort(&tif->tif_header.tiff_version);
		TIFFSwabLong(&tif->tif_header.tiff_diroff);
	}
	/*
	 * Now check version (if needed, it's been byte-swapped).
	 * Note that this isn't actually a version number, it's a
	 * magic number that doesn't change (stupid).
	 */
	if (tif->tif_header.tiff_version == TIFF_BIGTIFF_VERSION) {
		TIFFErrorExt(tif->tif_clientdata, name,
                          "This is a BigTIFF file.  This format not supported\n"
                          "by this version of libtiff." );
		goto bad;
	}
	if (tif->tif_header.tiff_version != TIFF_VERSION) {
		TIFFErrorExt(tif->tif_clientdata, name,
		    "Not a TIFF file, bad version number %d (0x%x)",
		    tif->tif_header.tiff_version,
		    tif->tif_header.tiff_version); 
		goto bad;
	}
	tif->tif_flags |= TIFF_MYBUFFER;
	tif->tif_rawcp = tif->tif_rawdata = 0;
	tif->tif_rawdatasize = 0;

	/*
	 * Sometimes we do not want to read the first directory (for example,
	 * it may be broken) and want to proceed to other directories. I this
	 * case we use the TIFF_HEADERONLY flag to open file and return
	 * immediately after reading TIFF header.
	 */
	if (tif->tif_flags & TIFF_HEADERONLY)
		return (tif);

	/*
	 * Setup initial directory.
	 */
	switch (mode[0]) {
	case 'r':
		tif->tif_nextdiroff = tif->tif_header.tiff_diroff;
		/*
		 * Try to use a memory-mapped file if the client
		 * has not explicitly suppressed usage with the
		 * 'm' flag in the open mode (see above).
		 */
		if ((tif->tif_flags & TIFF_MAPPED) &&
	!TIFFMapFileContents(tif, (tdata_t*) &tif->tif_base, &tif->tif_size))
			tif->tif_flags &= ~TIFF_MAPPED;
		if (TIFFReadDirectory(tif)) {
			tif->tif_rawcc = -1;
			tif->tif_flags |= TIFF_BUFFERSETUP;
			return (tif);
		}
		break;
	case 'a':
		/*
		 * New directories are automatically append
		 * to the end of the directory chain when they
		 * are written out (see TIFFWriteDirectory).
		 */
		if (!TIFFDefaultDirectory(tif))
			goto bad;
		return (tif);
	}
bad:
	tif->tif_mode = O_RDONLY;	/* XXX avoid flush */
        TIFFCleanup(tif);
bad2:
	return ((TIFF*)0);
}

/*
 * Query functions to access private data.
 */

/*
 * Return open file's name.
 */
const char *
TIFFFileName(TIFF* tif)
{
	return (tif->tif_name);
}

/*
 * Set the file name.
 */
const char *
TIFFSetFileName(TIFF* tif, const char *name)
{
	const char* old_name = tif->tif_name;
	tif->tif_name = (char *)name;
	return (old_name);
}

/*
 * Return open file's I/O descriptor.
 */
int
TIFFFileno(TIFF* tif)
{
	return (tif->tif_fd);
}

/*
 * Set open file's I/O descriptor, and return previous value.
 */
int
TIFFSetFileno(TIFF* tif, int fd)
{
        int old_fd = tif->tif_fd;
	tif->tif_fd = fd;
	return old_fd;
}

/*
 * Return open file's clientdata.
 */
thandle_t
TIFFClientdata(TIFF* tif)
{
	return (tif->tif_clientdata);
}

/*
 * Set open file's clientdata, and return previous value.
 */
thandle_t
TIFFSetClientdata(TIFF* tif, thandle_t newvalue)
{
	thandle_t m = tif->tif_clientdata;
	tif->tif_clientdata = newvalue;
	return m;
}

/*
 * Return read/write mode.
 */
int
TIFFGetMode(TIFF* tif)
{
	return (tif->tif_mode);
}

/*
 * Return read/write mode.
 */
int
TIFFSetMode(TIFF* tif, int mode)
{
	int old_mode = tif->tif_mode;
	tif->tif_mode = mode;
	return (old_mode);
}

/*
 * Return nonzero if file is organized in
 * tiles; zero if organized as strips.
 */
int
TIFFIsTiled(TIFF* tif)
{
	return (isTiled(tif));
}

/*
 * Return current row being read/written.
 */
uint32
TIFFCurrentRow(TIFF* tif)
{
	return (tif->tif_row);
}

/*
 * Return index of the current directory.
 */
tdir_t
TIFFCurrentDirectory(TIFF* tif)
{
	return (tif->tif_curdir);
}

/*
 * Return current strip.
 */
tstrip_t
TIFFCurrentStrip(TIFF* tif)
{
	return (tif->tif_curstrip);
}

/*
 * Return current tile.
 */
ttile_t
TIFFCurrentTile(TIFF* tif)
{
	return (tif->tif_curtile);
}

/*
 * Return nonzero if the file has byte-swapped data.
 */
int
TIFFIsByteSwapped(TIFF* tif)
{
	return ((tif->tif_flags & TIFF_SWAB) != 0);
}

/*
 * Return nonzero if the data is returned up-sampled.
 */
int
TIFFIsUpSampled(TIFF* tif)
{
	return (isUpSampled(tif));
}

/*
 * Return nonzero if the data is returned in MSB-to-LSB bit order.
 */
int
TIFFIsMSB2LSB(TIFF* tif)
{
	return (isFillOrder(tif, FILLORDER_MSB2LSB));
}

/*
 * Return nonzero if given file was written in big-endian order.
 */
int
TIFFIsBigEndian(TIFF* tif)
{
	return (tif->tif_header.tiff_magic == TIFF_BIGENDIAN);
}

/*
 * Return pointer to file read method.
 */
TIFFReadWriteProc
TIFFGetReadProc(TIFF* tif)
{
	return (tif->tif_readproc);
}

/*
 * Return pointer to file write method.
 */
TIFFReadWriteProc
TIFFGetWriteProc(TIFF* tif)
{
	return (tif->tif_writeproc);
}

/*
 * Return pointer to file seek method.
 */
TIFFSeekProc
TIFFGetSeekProc(TIFF* tif)
{
	return (tif->tif_seekproc);
}

/*
 * Return pointer to file close method.
 */
TIFFCloseProc
TIFFGetCloseProc(TIFF* tif)
{
	return (tif->tif_closeproc);
}

/*
 * Return pointer to file size requesting method.
 */
TIFFSizeProc
TIFFGetSizeProc(TIFF* tif)
{
	return (tif->tif_sizeproc);
}

/*
 * Return pointer to memory mapping method.
 */
TIFFMapFileProc
TIFFGetMapFileProc(TIFF* tif)
{
	return (tif->tif_mapproc);
}

/*
 * Return pointer to memory unmapping method.
 */
TIFFUnmapFileProc
TIFFGetUnmapFileProc(TIFF* tif)
{
	return (tif->tif_unmapproc);
}

/* vim: set ts=8 sts=8 sw=8 noet: */