/* $Id: tif_open.c,v 1.46 2010-12-06 16:54:54 faxguy 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.

 */

#include "tiffiop.h"

/*

 * Dummy functions to fill the omitted client procedures.

 */

static int

_tiffDummyMapProc(thandle_t fd, void** pbase, toff_t* psize)

{

	(void) fd; (void) pbase; (void) psize;

	return (0);

}

static void

_tiffDummyUnmapProc(thandle_t fd, void* base, toff_t size)

{

	(void) fd; (void) base; (void) size;

}

int

_TIFFgetMode(const char* mode, const char* module)

{

	int m = -1;

	switch (mode[0]) {

	case 'r':

		m = O_RDONLY;

		if (mode[1] == '+')

			m = O_RDWR;

		break;

	case 'w':

	case 'a':

		m = O_RDWR|O_CREAT;

		if (mode[0] == 'w')

			m |= O_TRUNC;

		break;

	default:

		TIFFErrorExt(0, module, "\"%s\": Bad mode", mode);

		break;

	}

	return (m);

}

TIFF*

TIFFClientOpen(

	const char* name, const char* mode,

	thandle_t clientdata,

	TIFFReadWriteProc readproc,

	TIFFReadWriteProc writeproc,

	TIFFSeekProc seekproc,

	TIFFCloseProc closeproc,

	TIFFSizeProc sizeproc,

	TIFFMapFileProc mapproc,

	TIFFUnmapFileProc unmapproc

)

{

	static const char module[] = "TIFFClientOpen";

	TIFF *tif;

	int m;

	const char* cp;

	/* The following are configuration checks. They should be redundant, but should not

	 * compile to any actual code in an optimised release build anyway. If any of them

	 * fail, (makefile-based or other) configuration is not correct */

	assert(sizeof(uint8)==1);

	assert(sizeof(int8)==1);

	assert(sizeof(uint16)==2);

	assert(sizeof(int16)==2);

	assert(sizeof(uint32)==4);

	assert(sizeof(int32)==4);

	assert(sizeof(uint64)==8);

	assert(sizeof(int64)==8);

	assert(sizeof(tmsize_t)==sizeof(void*));

	{

		union{

			uint8 a8[2];

			uint16 a16;

		} n;

		n.a8[0]=1;

		n.a8[1]=0;

		#ifdef WORDS_BIGENDIAN

		assert(n.a16==256);

		#else

		assert(n.a16==1);

		#endif

	}

	m = _TIFFgetMode(mode, module);

	if (m == -1)

		goto bad2;

	tif = (TIFF *)_TIFFmalloc((tmsize_t)(sizeof (TIFF) + strlen(name) + 1));

	if (tif == NULL) {

		TIFFErrorExt(clientdata, module, "%s: Out of memory (TIFF structure)", name);

		goto bad2;

	}

	_TIFFmemset(tif, 0, sizeof (*tif));

	tif->tif_name = (char *)tif + sizeof (TIFF);

	strcpy(tif->tif_name, name);

	tif->tif_mode = m &~ (O_CREAT|O_TRUNC);

	tif->tif_curdir = (uint16) -1;		/* non-existent directory */

	tif->tif_curoff = 0;

	tif->tif_curstrip = (uint32) -1;	/* invalid strip */

	tif->tif_row = (uint32) -1;		/* read/write pre-increment */

	tif->tif_clientdata = clientdata;

	if (!readproc || !writeproc || !seekproc || !closeproc || !sizeproc) {

		TIFFErrorExt(clientdata, module,

		    "One of the client procedures is NULL pointer.");

		goto bad2;

	}

	tif->tif_readproc = readproc;

	tif->tif_writeproc = writeproc;

	tif->tif_seekproc = seekproc;

	tif->tif_closeproc = closeproc;

	tif->tif_sizeproc = sizeproc;

	if (mapproc)

		tif->tif_mapproc = mapproc;

	else

		tif->tif_mapproc = _tiffDummyMapProc;

	if (unmapproc)

		tif->tif_unmapproc = unmapproc;

	else

		tif->tif_unmapproc = _tiffDummyUnmapProc;

	_TIFFSetDefaultCompressionState(tif);    /* setup default state */

	/*

	 * Default is to return data MSB2LSB and enable the

	 * use of memory-mapped files and strip chopping when

	 * a file is opened read-only.

	 */

	tif->tif_flags = FILLORDER_MSB2LSB;

	if (m == O_RDONLY )

		tif->tif_flags |= TIFF_MAPPED;

	#ifdef STRIPCHOP_DEFAULT

	if (m == O_RDONLY || m == O_RDWR)

		tif->tif_flags |= STRIPCHOP_DEFAULT;

	#endif

	/*

	 * Process library-specific flags in the open mode string.

	 * The following flags may be used to control intrinsic library

	 * behaviour that may or may not be desirable (usually for

	 * compatibility with some application that claims to support

	 * TIFF but only supports some braindead idea of what the

	 * vendor thinks TIFF is):

	 *

	 * 'l' use little-endian byte order for creating a file

	 * 'b' use big-endian byte order for creating a file

	 * 'L' read/write information using LSB2MSB bit order

	 * 'B' read/write information using MSB2LSB bit order

	 * 'H' read/write information using host bit order

	 * 'M' enable use of memory-mapped files when supported

	 * 'm' disable use of memory-mapped files

	 * 'C' enable strip chopping support when reading

	 * 'c' disable strip chopping support

	 * 'h' read TIFF header only, do not load the first IFD

	 * '4' ClassicTIFF for creating a file (default)

	 * '8' BigTIFF for creating a file

	 *

	 * The use of the 'l' and 'b' flags is strongly discouraged.

	 * These flags are provided solely because numerous vendors,

	 * typically on the PC, do not correctly support TIFF; they

	 * only support the Intel little-endian byte order.  This

	 * support is not configured by default because it supports

	 * the violation of the TIFF spec that says that readers *MUST*

	 * support both byte orders.  It is strongly recommended that

	 * you not use this feature except to deal with busted apps

	 * that write invalid TIFF.  And even in those cases you should

	 * bang on the vendors to fix their software.

	 *

	 * The 'L', 'B', and 'H' flags are intended for applications

	 * that can optimize operations on data by using a particular

	 * bit order.  By default the library returns data in MSB2LSB

	 * bit order for compatibiltiy with older versions of this

	 * library.  Returning data in the bit order of the native cpu

	 * makes the most sense but also requires applications to check

	 * the value of the FillOrder tag; something they probably do

	 * not do right now.

	 *

	 * The 'M' and 'm' flags are provided because some virtual memory

	 * systems exhibit poor behaviour when large images are mapped.

	 * These options permit clients to control the use of memory-mapped

	 * files on a per-file basis.

	 *

	 * The 'C' and 'c' flags are provided because the library support

	 * for chopping up large strips into multiple smaller strips is not

	 * application-transparent and as such can cause problems.  The 'c'

	 * option permits applications that only want to look at the tags,

	 * for example, to get the unadulterated TIFF tag information.

	 */

	for (cp = mode; *cp; cp++)

		switch (*cp) {

			case 'b':

				#ifndef WORDS_BIGENDIAN

				if (m&O_CREAT)

					tif->tif_flags |= TIFF_SWAB;

				#endif

				break;

			case 'l':

				#ifdef WORDS_BIGENDIAN

				if ((m&O_CREAT))

					tif->tif_flags |= TIFF_SWAB;

				#endif

				break;

			case 'B':

				tif->tif_flags = (tif->tif_flags &~ TIFF_FILLORDER) |

				    FILLORDER_MSB2LSB;

				break;

			case 'L':

				tif->tif_flags = (tif->tif_flags &~ TIFF_FILLORDER) |

				    FILLORDER_LSB2MSB;

				break;

			case 'H':

				tif->tif_flags = (tif->tif_flags &~ TIFF_FILLORDER) |

				    HOST_FILLORDER;

				break;

			case 'M':

				if (m == O_RDONLY)

					tif->tif_flags |= TIFF_MAPPED;

				break;

			case 'm':

				if (m == O_RDONLY)

					tif->tif_flags &= ~TIFF_MAPPED;

				break;

			case 'C':

				if (m == O_RDONLY)

					tif->tif_flags |= TIFF_STRIPCHOP;

				break;

			case 'c':

				if (m == O_RDONLY)

					tif->tif_flags &= ~TIFF_STRIPCHOP;

				break;

			case 'h':

				tif->tif_flags |= TIFF_HEADERONLY;

				break;

			case '8':

				if (m&O_CREAT)

					tif->tif_flags |= TIFF_BIGTIFF;

				break;

		}

	/*

	 * Read in TIFF header.

	 */

	if ((m & O_TRUNC) ||

	    !ReadOK(tif, &tif->tif_header, sizeof (TIFFHeaderClassic))) {

		if (tif->tif_mode == O_RDONLY) {

			TIFFErrorExt(tif->tif_clientdata, name,

			    "Cannot read TIFF header");

			goto bad;

		}

		/*

		 * Setup header and write.

		 */

		#ifdef WORDS_BIGENDIAN

		tif->tif_header.common.tiff_magic = tif->tif_flags & TIFF_SWAB

		    ? TIFF_LITTLEENDIAN : TIFF_BIGENDIAN;

		#else

		tif->tif_header.common.tiff_magic = tif->tif_flags & TIFF_SWAB

		    ? TIFF_BIGENDIAN : TIFF_LITTLEENDIAN;

		#endif

		if (!(tif->tif_flags&TIFF_BIGTIFF))

		{

			tif->tif_header.common.tiff_version = TIFF_VERSION_CLASSIC;

			tif->tif_header.classic.tiff_diroff = 0;

			if (tif->tif_flags & TIFF_SWAB)

				TIFFSwabShort(&tif->tif_header.common.tiff_version);

			tif->tif_header_size = sizeof(TIFFHeaderClassic);

		}

		else

		{

			tif->tif_header.common.tiff_version = TIFF_VERSION_BIG;

			tif->tif_header.big.tiff_offsetsize = 8;

			tif->tif_header.big.tiff_unused = 0;

			tif->tif_header.big.tiff_diroff = 0;

			if (tif->tif_flags & TIFF_SWAB)

			{

				TIFFSwabShort(&tif->tif_header.common.tiff_version);

				TIFFSwabShort(&tif->tif_header.big.tiff_offsetsize);

			}

			tif->tif_header_size = sizeof (TIFFHeaderBig);

		}

		/*

		 * The doc for "fopen" for some STD_C_LIBs says that if you

		 * open a file for modify ("+"), then you must fseek (or

		 * fflush?) between any freads and fwrites.  This is not

		 * necessary on most systems, but has been shown to be needed

		 * on Solaris.

		 */

		TIFFSeekFile( tif, 0, SEEK_SET );

		if (!WriteOK(tif, &tif->tif_header, (tmsize_t)(tif->tif_header_size))) {

			TIFFErrorExt(tif->tif_clientdata, name,

			    "Error writing TIFF header");

			goto bad;

		}

		/*

		 * Setup the byte order handling.

		 */

		if (tif->tif_header.common.tiff_magic == TIFF_BIGENDIAN) {

			#ifndef WORDS_BIGENDIAN

			tif->tif_flags |= TIFF_SWAB;

			#endif

		} else {

			#ifdef WORDS_BIGENDIAN

			tif->tif_flags |= TIFF_SWAB;

			#endif

		}

		/*

		 * Setup default directory.

		 */

		if (!TIFFDefaultDirectory(tif))

			goto bad;

		tif->tif_diroff = 0;

		tif->tif_dirlist = NULL;

		tif->tif_dirlistsize = 0;

		tif->tif_dirnumber = 0;

		return (tif);

	}

	/*

	 * Setup the byte order handling.

	 */

	if (tif->tif_header.common.tiff_magic != TIFF_BIGENDIAN &&

	    tif->tif_header.common.tiff_magic != TIFF_LITTLEENDIAN

	    #if MDI_SUPPORT

	    &&

	    #if HOST_BIGENDIAN

	    tif->tif_header.common.tiff_magic != MDI_BIGENDIAN

	    #else

	    tif->tif_header.common.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.common.tiff_magic,

		    tif->tif_header.common.tiff_magic);

		goto bad;

	}

	if (tif->tif_header.common.tiff_magic == TIFF_BIGENDIAN) {

		#ifndef WORDS_BIGENDIAN

		tif->tif_flags |= TIFF_SWAB;

		#endif

	} else {

		#ifdef WORDS_BIGENDIAN

		tif->tif_flags |= TIFF_SWAB;

		#endif

	}

	if (tif->tif_flags & TIFF_SWAB) 

		TIFFSwabShort(&tif->tif_header.common.tiff_version);

	if ((tif->tif_header.common.tiff_version != TIFF_VERSION_CLASSIC)&&

	    (tif->tif_header.common.tiff_version != TIFF_VERSION_BIG)) {

		TIFFErrorExt(tif->tif_clientdata, name,

		    "Not a TIFF file, bad version number %d (0x%x)",

		    tif->tif_header.common.tiff_version,

		    tif->tif_header.common.tiff_version);

		goto bad;

	}

	if (tif->tif_header.common.tiff_version == TIFF_VERSION_CLASSIC)

	{

		if (tif->tif_flags & TIFF_SWAB)

			TIFFSwabLong(&tif->tif_header.classic.tiff_diroff);

		tif->tif_header_size = sizeof(TIFFHeaderClassic);

	}

	else

	{

		if (!ReadOK(tif, ((uint8*)(&tif->tif_header) + sizeof(TIFFHeaderClassic)), (sizeof(TIFFHeaderBig)-sizeof(TIFFHeaderClassic))))

		{

			TIFFErrorExt(tif->tif_clientdata, name,

			    "Cannot read TIFF header");

			goto bad;

		}

		if (tif->tif_flags & TIFF_SWAB)

		{

			TIFFSwabShort(&tif->tif_header.big.tiff_offsetsize);

			TIFFSwabLong8(&tif->tif_header.big.tiff_diroff);

		}

		if (tif->tif_header.big.tiff_offsetsize != 8)

		{

			TIFFErrorExt(tif->tif_clientdata, name,

			    "Not a TIFF file, bad BigTIFF offsetsize %d (0x%x)",

			    tif->tif_header.big.tiff_offsetsize,

			    tif->tif_header.big.tiff_offsetsize);

			goto bad;

		}

		if (tif->tif_header.big.tiff_unused != 0)

		{

			TIFFErrorExt(tif->tif_clientdata, name,

			    "Not a TIFF file, bad BigTIFF unused %d (0x%x)",

			    tif->tif_header.big.tiff_unused,

			    tif->tif_header.big.tiff_unused);

			goto bad;

		}

		tif->tif_header_size = sizeof(TIFFHeaderBig);

		tif->tif_flags |= TIFF_BIGTIFF;

	}

	tif->tif_flags |= TIFF_MYBUFFER;

	tif->tif_rawcp = tif->tif_rawdata = 0;

	tif->tif_rawdatasize = 0;

        tif->tif_rawdataoff = 0;

        tif->tif_rawdataloaded = 0;

	switch (mode[0]) {

		case 'r':

			if (!(tif->tif_flags&TIFF_BIGTIFF))

				tif->tif_nextdiroff = tif->tif_header.classic.tiff_diroff;

			else

				tif->tif_nextdiroff = tif->tif_header.big.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)

			{

				toff_t n;

				if (TIFFMapFileContents(tif,(void**)(&tif->tif_base),&n))

				{

					tif->tif_size=(tmsize_t)n;

					assert((toff_t)tif->tif_size==n);

				}

				else

					tif->tif_flags &= ~TIFF_MAPPED;

			}

			/*

			 * 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.

			 */

			if (TIFFReadDirectory(tif)) {

				tif->tif_rawcc = (tmsize_t)-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.

 */

uint16

TIFFCurrentDirectory(TIFF* tif)

{

	return (tif->tif_curdir);

}

/*

 * Return current strip.

 */

uint32

TIFFCurrentStrip(TIFF* tif)

{

	return (tif->tif_curstrip);

}

/*

 * Return current tile.

 */

uint32

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.common.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: */

/*

 * Local Variables:

 * mode: c

 * c-basic-offset: 8

 * fill-column: 78

 * End:

 */