Source/LibTIFF/tif_vms.c - platform/external/free-image - Git at Google

 /* $Id: tif_vms.c,v 1.12 2009/07/14 21:10:27 drolon 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 VMS-specific Routines.
  */

 #include <stdlib.h>
 #include <unixio.h>
 #include "tiffiop.h"
 #if !HAVE_IEEEFP
 #include <math.h>
 #endif

 #ifdef VAXC
 #define	NOSHARE	noshare
 #else
 #define	NOSHARE
 #endif

 #ifdef __alpha
 /* Dummy entry point for backwards compatibility */
 void TIFFModeCCITTFax3(void){}
 #endif

 static tsize_t
 _tiffReadProc(thandle_t fd, tdata_t buf, tsize_t size)
 {
 	return (read((int) fd, buf, size));
 }

 static tsize_t
 _tiffWriteProc(thandle_t fd, tdata_t buf, tsize_t size)
 {
 	return (write((int) fd, buf, size));
 }

 static toff_t
 _tiffSeekProc(thandle_t fd, toff_t off, int whence)
 {
 	return ((toff_t) lseek((int) fd, (off_t) off, whence));
 }

 static int
 _tiffCloseProc(thandle_t fd)
 {
 	return (close((int) fd));
 }

 #include <sys/stat.h>

 static toff_t
 _tiffSizeProc(thandle_t fd)
 {
 	struct stat sb;
 	return (toff_t) (fstat((int) fd, &sb) < 0 ? 0 : sb.st_size);
 }

 #ifdef HAVE_MMAP
 #include <starlet.h>
 #include <fab.h>
 #include <secdef.h>

 /*
  * Table for storing information on current open sections.
  * (Should really be a linked list)
  */
 #define MAX_MAPPED 100
 static int no_mapped = 0;
 static struct {
 	char *base;
 	char *top;
 	unsigned short channel;
 } map_table[MAX_MAPPED];

 /*
  * This routine maps a file into a private section. Note that this
  * method of accessing a file is by far the fastest under VMS.
  * The routine may fail (i.e. return 0) for several reasons, for
  * example:
  * - There is no more room for storing the info on sections.
  * - The process is out of open file quota, channels, ...
  * - fd does not describe an opened file.
  * - The file is already opened for write access by this process
  *   or another process
  * - There is no free "hole" in virtual memory that fits the
  *   size of the file
  */
 static int
 _tiffMapProc(thandle_t fd, tdata_t* pbase, toff_t* psize)
 {
 	char name[256];
 	struct FAB fab;
 	unsigned short channel;
 	char *inadr[2], *retadr[2];
 	unsigned long status;
 	long size;

 	if (no_mapped >= MAX_MAPPED)
 		return(0);
 	/*
 	 * We cannot use a file descriptor, we
 	 * must open the file once more.
 	 */
 	if (getname((int)fd, name, 1) == NULL)
 		return(0);
 	/* prepare the FAB for a user file open */
 	fab = cc$rms_fab;
 	fab.fab$l_fop |= FAB$V_UFO;
 	fab.fab$b_fac = FAB$M_GET;
 	fab.fab$b_shr = FAB$M_SHRGET;
 	fab.fab$l_fna = name;
 	fab.fab$b_fns = strlen(name);
 	status = sys$open(&fab);	/* open file & get channel number */
 	if ((status&1) == 0)
 		return(0);
 	channel = (unsigned short)fab.fab$l_stv;
 	inadr[0] = inadr[1] = (char *)0; /* just an address in P0 space */
 	/*
 	 * Map the blocks of the file up to
 	 * the EOF block into virtual memory.
 	 */
 	size = _tiffSizeProc(fd);
 	status = sys$crmpsc(inadr, retadr, 0, SEC$M_EXPREG, 0,0,0, channel,
 		TIFFhowmany(size,512), 0,0,0);
 	if ((status&1) == 0){
 		sys$dassgn(channel);
 		return(0);
 	}
 	*pbase = (tdata_t) retadr[0];	/* starting virtual address */
 	/*
 	 * Use the size of the file up to the
 	 * EOF mark for UNIX compatibility.
 	 */
 	*psize = (toff_t) size;
 	/* Record the section in the table */
 	map_table[no_mapped].base = retadr[0];
 	map_table[no_mapped].top = retadr[1];
 	map_table[no_mapped].channel = channel;
 	no_mapped++;

         return(1);
 }

 /*
  * This routine unmaps a section from the virtual address space of
  * the process, but only if the base was the one returned from a
  * call to TIFFMapFileContents.
  */
 static void
 _tiffUnmapProc(thandle_t fd, tdata_t base, toff_t size)
 {
 	char *inadr[2];
 	int i, j;

 	/* Find the section in the table */
 	for (i = 0;i < no_mapped; i++) {
 		if (map_table[i].base == (char *) base) {
 			/* Unmap the section */
 			inadr[0] = (char *) base;
 			inadr[1] = map_table[i].top;
 			sys$deltva(inadr, 0, 0);
 			sys$dassgn(map_table[i].channel);
 			/* Remove this section from the list */
 			for (j = i+1; j < no_mapped; j++)
 				map_table[j-1] = map_table[j];
 			no_mapped--;
 			return;
 		}
 	}
 }
 #else /* !HAVE_MMAP */
 static int
 _tiffMapProc(thandle_t fd, tdata_t* pbase, toff_t* psize)
 {
 	return (0);
 }

 static void
 _tiffUnmapProc(thandle_t fd, tdata_t base, toff_t size)
 {
 }
 #endif /* !HAVE_MMAP */

 /*
  * Open a TIFF file descriptor for read/writing.
  */
 TIFF*
 TIFFFdOpen(int fd, const char* name, const char* mode)
 {
 	TIFF* tif;

 	tif = TIFFClientOpen(name, mode,
 	    (thandle_t) fd,
 	    _tiffReadProc, _tiffWriteProc, _tiffSeekProc, _tiffCloseProc,
 	    _tiffSizeProc, _tiffMapProc, _tiffUnmapProc);
 	if (tif)
 		tif->tif_fd = fd;
 	return (tif);
 }

 /*
  * Open a TIFF file for read/writing.
  */
 TIFF*
 TIFFOpen(const char* name, const char* mode)
 {
 	static const char module[] = "TIFFOpen";
 	int m, fd;

 	m = _TIFFgetMode(mode, module);
 	if (m == -1)
 		return ((TIFF*)0);
         if (m&O_TRUNC){
                 /*
 		 * There is a bug in open in VAXC. If you use
 		 * open w/ m=O_RDWR|O_CREAT|O_TRUNC the
 		 * wrong thing happens.  On the other hand
 		 * creat does the right thing.
                  */
                 fd = creat((char *) /* bug in stdio.h */ name, 0666,
 		    "alq = 128", "deq = 64", "mbc = 32",
 		    "fop = tef");
 	} else if (m&O_RDWR) {
 		fd = open(name, m, 0666,
 		    "deq = 64", "mbc = 32", "fop = tef", "ctx = stm");
 	} else
 		fd = open(name, m, 0666, "mbc = 32", "ctx = stm");
 	if (fd < 0) {
 		TIFFErrorExt(0, module, "%s: Cannot open", name);
 		return ((TIFF*)0);
 	}
 	return (TIFFFdOpen(fd, name, mode));
 }

 tdata_t
 _TIFFmalloc(tsize_t s)
 {
 	return (malloc((size_t) s));
 }

 void
 _TIFFfree(tdata_t p)
 {
 	free(p);
 }

 tdata_t
 _TIFFrealloc(tdata_t p, tsize_t s)
 {
 	return (realloc(p, (size_t) s));
 }

 void
 _TIFFmemset(tdata_t p, int v, tsize_t c)
 {
 	memset(p, v, (size_t) c);
 }

 void
 _TIFFmemcpy(tdata_t d, const tdata_t s, tsize_t c)
 {
 	memcpy(d, s, (size_t) c);
 }

 int
 _TIFFmemcmp(const tdata_t p1, const tdata_t p2, tsize_t c)
 {
 	return (memcmp(p1, p2, (size_t) c));
 }

 /*
  * On the VAX, we need to make those global, writable pointers
  * non-shareable, otherwise they would be made shareable by default.
  * On the AXP, this brain damage has been corrected.
  *
  * I (Karsten Spang, krs@kampsax.dk) have dug around in the GCC
  * manual and the GAS code and have come up with the following
  * construct, but I don't have GCC on my VAX, so it is untested.
  * Please tell me if it does not work.
  */

 static void
 vmsWarningHandler(const char* module, const char* fmt, va_list ap)
 {
 	if (module != NULL)
 		fprintf(stderr, "%s: ", module);
 	fprintf(stderr, "Warning, ");
 	vfprintf(stderr, fmt, ap);
 	fprintf(stderr, ".\n");
 }

 NOSHARE TIFFErrorHandler _TIFFwarningHandler = vmsWarningHandler
 #if defined(VAX) && defined(__GNUC__)
 asm("_$$PsectAttributes_NOSHR$$_TIFFwarningHandler")
 #endif
 ;

 static void
 vmsErrorHandler(const char* module, const char* fmt, va_list ap)
 {
 	if (module != NULL)
 		fprintf(stderr, "%s: ", module);
 	vfprintf(stderr, fmt, ap);
 	fprintf(stderr, ".\n");
 }

 NOSHARE TIFFErrorHandler _TIFFerrorHandler = vmsErrorHandler
 #if defined(VAX) && defined(__GNUC__)
 asm("_$$PsectAttributes_NOSHR$$_TIFFerrorHandler")
 #endif
 ;


 #if !HAVE_IEEEFP
 /* IEEE floting point handling */

 typedef	struct ieeedouble {
 	unsigned long	mant2;          /* fix NDR: full 8-byte swap */
 	unsigned long	mant	: 20,
 		        exp	: 11,
 		        sign	: 1;
 } ieeedouble;
 typedef	struct ieeefloat {
 	unsigned long   mant	: 23,
 		        exp	: 8,
 		        sign	: 1;
 } ieeefloat;

 /*
  * NB: These are D_FLOAT's, not G_FLOAT's. A G_FLOAT is
  *  simply a reverse-IEEE float/double.
  */

 typedef	struct {
 	unsigned long	mant1	: 7,
 		        exp	: 8,
 		        sign	: 1,
 		        mant2	: 16,
 		        mant3   : 16,
 		        mant4   : 16;
 } nativedouble;
 typedef	struct {
 	unsigned long	mant1	: 7,
 		        exp	: 8,
 		        sign	: 1,
 		        mant2	: 16;
 } nativefloat;

 typedef	union {
 	ieeedouble	ieee;
 	nativedouble	native;
 	char		b[8];
 	uint32		l[2];
 	double		d;
 } double_t;

 typedef	union {
 	ieeefloat	ieee;
 	nativefloat	native;
 	char		b[4];
 	uint32		l;
 	float		f;
 } float_t;

 #if defined(VAXC) || defined(DECC)
 #pragma inline(ieeetod,dtoieee)
 #endif

 /*
  * Convert an IEEE double precision number to native double precision.
  * The source is contained in two longwords, the second holding the sign,
  * exponent and the higher order bits of the mantissa, and the first
  * holding the rest of the mantissa as follows:
  * (Note: It is assumed that the number has been eight-byte swapped to
  * LSB first.)
  *
  * First longword:
  *	32 least significant bits of mantissa
  * Second longword:
  *	0-19:	20 most significant bits of mantissa
  *	20-30:	exponent
  *	31:	sign
  * The exponent is stored as excess 1023.
  * The most significant bit of the mantissa is implied 1, and not stored.
  * If the exponent and mantissa are zero, the number is zero.
  * If the exponent is 0 (i.e. -1023) and the mantissa is non-zero, it is an
  * unnormalized number with the most significant bit NOT implied.
  * If the exponent is 2047, the number is invalid, in case the mantissa is zero,
  * this means overflow (+/- depending of the sign bit), otherwise
  * it simply means invalid number.
  *
  * If the number is too large for the machine or was specified as overflow,
  * +/-HUGE_VAL is returned.
  */
 INLINE static void
 ieeetod(double *dp)
 {
 	double_t source;
 	long sign,exp,mant;
 	double dmant;

 	source.ieee = ((double_t*)dp)->ieee;
 	sign = source.ieee.sign;
 	exp = source.ieee.exp;
 	mant = source.ieee.mant;

 	if (exp == 2047) {
 		if (mant)			/* Not a Number (NAN) */
 			*dp = HUGE_VAL;
 		else				/* +/- infinity */
 			*dp = (sign ? -HUGE_VAL : HUGE_VAL);
 		return;
 	}
 	if (!exp) {
 		if (!(mant || source.ieee.mant2)) {	/* zero */
 			*dp=0;
 			return;
 		} else {			/* Unnormalized number */
 			/* NB: not -1023, the 1 bit is not implied */
 			exp= -1022;
 		}
 	} else {
 		mant |= 1<<20;
 		exp -= 1023;
 	}
 	dmant = (((double) mant) +
 		((double) source.ieee.mant2) / (((double) (1<<16)) *
 		((double) (1<<16)))) / (double) (1<<20);
 	dmant = ldexp(dmant, exp);
 	if (sign)
 		dmant= -dmant;
 	*dp = dmant;
 }

 INLINE static void
 dtoieee(double *dp)
 {
 	double_t num;
 	double x;
 	int exp;

 	num.d = *dp;
 	if (!num.d) {			/* Zero is just binary all zeros */
 		num.l[0] = num.l[1] = 0;
 		return;
 	}

 	if (num.d < 0) {		/* Sign is encoded separately */
 		num.d = -num.d;
 		num.ieee.sign = 1;
 	} else {
 		num.ieee.sign = 0;
 	}

 	/* Now separate the absolute value into mantissa and exponent */
 	x = frexp(num.d, &exp);

 	/*
 	 * Handle cases where the value is outside the
 	 * range for IEEE floating point numbers.
 	 * (Overflow cannot happen on a VAX, but underflow
 	 * can happen for G float.)
 	 */
 	if (exp < -1022) {		/* Unnormalized number */
 		x = ldexp(x, -1023-exp);
 		exp = 0;
 	} else if (exp > 1023) {	/* +/- infinity */
 		x = 0;
 		exp = 2047;
 	} else {			/* Get rid of most significant bit */
 		x *= 2;
 		x -= 1;
 		exp += 1022; /* fix NDR: 1.0 -> x=0.5, exp=1 -> ieee.exp = 1023 */
 	}
 	num.ieee.exp = exp;

 	x *= (double) (1<<20);
 	num.ieee.mant = (long) x;
 	x -= (double) num.ieee.mant;
 	num.ieee.mant2 = (long) (x*((double) (1<<16)*(double) (1<<16)));

 	if (!(num.ieee.mant || num.ieee.exp || num.ieee.mant2)) {
 		/* Avoid negative zero */
 		num.ieee.sign = 0;
 	}
 	((double_t*)dp)->ieee = num.ieee;
 }

 /*
  * Beware, these do not handle over/under-flow
  * during conversion from ieee to native format.
  */
 #define	NATIVE2IEEEFLOAT(fp) { \
     float_t t; \
     if (t.ieee.exp = (fp)->native.exp) \
 	t.ieee.exp += -129 + 127; \
     t.ieee.sign = (fp)->native.sign; \
     t.ieee.mant = ((fp)->native.mant1<<16)|(fp)->native.mant2; \
     *(fp) = t; \
 }
 #define	IEEEFLOAT2NATIVE(fp) { \
     float_t t; int v = (fp)->ieee.exp; \
     if (v) v += -127 + 129;		/* alter bias of exponent */\
     t.native.exp = v;			/* implicit truncation of exponent */\
     t.native.sign = (fp)->ieee.sign; \
     v = (fp)->ieee.mant; \
     t.native.mant1 = v >> 16; \
     t.native.mant2 = v;\
     *(fp) = t; \
 }

 #define IEEEDOUBLE2NATIVE(dp) ieeetod(dp)

 #define NATIVE2IEEEDOUBLE(dp) dtoieee(dp)


 /*
  * These unions are used during floating point
  * conversions.  The above macros define the
  * conversion operations.
  */
 void
 TIFFCvtIEEEFloatToNative(TIFF* tif, u_int n, float* f)
 {
 	float_t* fp = (float_t*) f;

 	while (n-- > 0) {
 		IEEEFLOAT2NATIVE(fp);
 		fp++;
 	}
 }

 void
 TIFFCvtNativeToIEEEFloat(TIFF* tif, u_int n, float* f)
 {
 	float_t* fp = (float_t*) f;

 	while (n-- > 0) {
 		NATIVE2IEEEFLOAT(fp);
 		fp++;
 	}
 }
 void
 TIFFCvtIEEEDoubleToNative(TIFF* tif, u_int n, double* f)
 {
 	double_t* fp = (double_t*) f;

 	while (n-- > 0) {
 		IEEEDOUBLE2NATIVE(fp);
 		fp++;
 	}
 }

 void
 TIFFCvtNativeToIEEEDouble(TIFF* tif, u_int n, double* f)
 {
 	double_t* fp = (double_t*) f;

 	while (n-- > 0) {
 		NATIVE2IEEEDOUBLE(fp);
 		fp++;
 	}
 }
 #endif
	/* $Id: tif_vms.c,v 1.12 2009/07/14 21:10:27 drolon 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 VMS-specific Routines.
	*/

	#include <stdlib.h>
	#include <unixio.h>
	#include "tiffiop.h"
	#if !HAVE_IEEEFP
	#include <math.h>
	#endif

	#ifdef VAXC
	#define NOSHARE noshare
	#else
	#define NOSHARE
	#endif

	#ifdef __alpha
	/* Dummy entry point for backwards compatibility */
	void TIFFModeCCITTFax3(void){}
	#endif

	static tsize_t
	_tiffReadProc(thandle_t fd, tdata_t buf, tsize_t size)
	{
	return (read((int) fd, buf, size));
	}

	static tsize_t
	_tiffWriteProc(thandle_t fd, tdata_t buf, tsize_t size)
	{
	return (write((int) fd, buf, size));
	}

	static toff_t
	_tiffSeekProc(thandle_t fd, toff_t off, int whence)
	{
	return ((toff_t) lseek((int) fd, (off_t) off, whence));
	}

	static int
	_tiffCloseProc(thandle_t fd)
	{
	return (close((int) fd));
	}

	#include <sys/stat.h>

	static toff_t
	_tiffSizeProc(thandle_t fd)
	{
	struct stat sb;
	return (toff_t) (fstat((int) fd, &sb) < 0 ? 0 : sb.st_size);
	}

	#ifdef HAVE_MMAP
	#include <starlet.h>
	#include <fab.h>
	#include <secdef.h>

	/*
	* Table for storing information on current open sections.
	* (Should really be a linked list)
	*/
	#define MAX_MAPPED 100
	static int no_mapped = 0;
	static struct {
	char *base;
	char *top;
	unsigned short channel;
	} map_table[MAX_MAPPED];

	/*
	* This routine maps a file into a private section. Note that this
	* method of accessing a file is by far the fastest under VMS.
	* The routine may fail (i.e. return 0) for several reasons, for
	* example:
	* - There is no more room for storing the info on sections.
	* - The process is out of open file quota, channels, ...
	* - fd does not describe an opened file.
	* - The file is already opened for write access by this process
	* or another process
	* - There is no free "hole" in virtual memory that fits the
	* size of the file
	*/
	static int
	_tiffMapProc(thandle_t fd, tdata_t* pbase, toff_t* psize)
	{
	char name[256];
	struct FAB fab;
	unsigned short channel;
	char inadr[2], retadr[2];
	unsigned long status;
	long size;

	if (no_mapped >= MAX_MAPPED)
	return(0);
	/*
	* We cannot use a file descriptor, we
	* must open the file once more.
	*/
	if (getname((int)fd, name, 1) == NULL)
	return(0);
	/* prepare the FAB for a user file open */
	fab = cc$rms_fab;
	fab.fab$l_fop \|= FAB$V_UFO;
	fab.fab$b_fac = FAB$M_GET;
	fab.fab$b_shr = FAB$M_SHRGET;
	fab.fab$l_fna = name;
	fab.fab$b_fns = strlen(name);
	status = sys$open(&fab); /* open file & get channel number */
	if ((status&1) == 0)
	return(0);
	channel = (unsigned short)fab.fab$l_stv;
	inadr[0] = inadr[1] = (char )0; / just an address in P0 space */
	/*
	* Map the blocks of the file up to
	* the EOF block into virtual memory.
	*/
	size = _tiffSizeProc(fd);
	status = sys$crmpsc(inadr, retadr, 0, SEC$M_EXPREG, 0,0,0, channel,
	TIFFhowmany(size,512), 0,0,0);
	if ((status&1) == 0){
	sys$dassgn(channel);
	return(0);
	}
	pbase = (tdata_t) retadr[0]; / starting virtual address */
	/*
	* Use the size of the file up to the
	* EOF mark for UNIX compatibility.
	*/
	*psize = (toff_t) size;
	/* Record the section in the table */
	map_table[no_mapped].base = retadr[0];
	map_table[no_mapped].top = retadr[1];
	map_table[no_mapped].channel = channel;
	no_mapped++;

	return(1);
	}

	/*
	* This routine unmaps a section from the virtual address space of
	* the process, but only if the base was the one returned from a
	* call to TIFFMapFileContents.
	*/
	static void
	_tiffUnmapProc(thandle_t fd, tdata_t base, toff_t size)
	{
	char *inadr[2];
	int i, j;

	/* Find the section in the table */
	for (i = 0;i < no_mapped; i++) {
	if (map_table[i].base == (char *) base) {
	/* Unmap the section */
	inadr[0] = (char *) base;
	inadr[1] = map_table[i].top;
	sys$deltva(inadr, 0, 0);
	sys$dassgn(map_table[i].channel);
	/* Remove this section from the list */
	for (j = i+1; j < no_mapped; j++)
	map_table[j-1] = map_table[j];
	no_mapped--;
	return;
	}
	}
	}
	#else /* !HAVE_MMAP */
	static int
	_tiffMapProc(thandle_t fd, tdata_t* pbase, toff_t* psize)
	{
	return (0);
	}

	static void
	_tiffUnmapProc(thandle_t fd, tdata_t base, toff_t size)
	{
	}
	#endif /* !HAVE_MMAP */

	/*
	* Open a TIFF file descriptor for read/writing.
	*/
	TIFF*
	TIFFFdOpen(int fd, const char* name, const char* mode)
	{
	TIFF* tif;

	tif = TIFFClientOpen(name, mode,
	(thandle_t) fd,
	_tiffReadProc, _tiffWriteProc, _tiffSeekProc, _tiffCloseProc,
	_tiffSizeProc, _tiffMapProc, _tiffUnmapProc);
	if (tif)
	tif->tif_fd = fd;
	return (tif);
	}

	/*
	* Open a TIFF file for read/writing.
	*/
	TIFF*
	TIFFOpen(const char* name, const char* mode)
	{
	static const char module[] = "TIFFOpen";
	int m, fd;

	m = _TIFFgetMode(mode, module);
	if (m == -1)
	return ((TIFF*)0);
	if (m&O_TRUNC){
	/*
	* There is a bug in open in VAXC. If you use
	* open w/ m=O_RDWR\|O_CREAT\|O_TRUNC the
	* wrong thing happens. On the other hand
	* creat does the right thing.
	*/
	fd = creat((char ) / bug in stdio.h */ name, 0666,
	"alq = 128", "deq = 64", "mbc = 32",
	"fop = tef");
	} else if (m&O_RDWR) {
	fd = open(name, m, 0666,
	"deq = 64", "mbc = 32", "fop = tef", "ctx = stm");
	} else
	fd = open(name, m, 0666, "mbc = 32", "ctx = stm");
	if (fd < 0) {
	TIFFErrorExt(0, module, "%s: Cannot open", name);
	return ((TIFF*)0);
	}
	return (TIFFFdOpen(fd, name, mode));
	}

	tdata_t
	_TIFFmalloc(tsize_t s)
	{
	return (malloc((size_t) s));
	}

	void
	_TIFFfree(tdata_t p)
	{
	free(p);
	}

	tdata_t
	_TIFFrealloc(tdata_t p, tsize_t s)
	{
	return (realloc(p, (size_t) s));
	}

	void
	_TIFFmemset(tdata_t p, int v, tsize_t c)
	{
	memset(p, v, (size_t) c);
	}

	void
	_TIFFmemcpy(tdata_t d, const tdata_t s, tsize_t c)
	{
	memcpy(d, s, (size_t) c);
	}

	int
	_TIFFmemcmp(const tdata_t p1, const tdata_t p2, tsize_t c)
	{
	return (memcmp(p1, p2, (size_t) c));
	}

	/*
	* On the VAX, we need to make those global, writable pointers
	* non-shareable, otherwise they would be made shareable by default.
	* On the AXP, this brain damage has been corrected.
	*
	* I (Karsten Spang, krs@kampsax.dk) have dug around in the GCC
	* manual and the GAS code and have come up with the following
	* construct, but I don't have GCC on my VAX, so it is untested.
	* Please tell me if it does not work.
	*/

	static void
	vmsWarningHandler(const char* module, const char* fmt, va_list ap)
	{
	if (module != NULL)
	fprintf(stderr, "%s: ", module);
	fprintf(stderr, "Warning, ");
	vfprintf(stderr, fmt, ap);
	fprintf(stderr, ".\n");
	}

	NOSHARE TIFFErrorHandler _TIFFwarningHandler = vmsWarningHandler
	#if defined(VAX) && defined(__GNUC__)
	asm("_$$PsectAttributes_NOSHR$$_TIFFwarningHandler")
	#endif
	;

	static void
	vmsErrorHandler(const char* module, const char* fmt, va_list ap)
	{
	if (module != NULL)
	fprintf(stderr, "%s: ", module);
	vfprintf(stderr, fmt, ap);
	fprintf(stderr, ".\n");
	}

	NOSHARE TIFFErrorHandler _TIFFerrorHandler = vmsErrorHandler
	#if defined(VAX) && defined(__GNUC__)
	asm("_$$PsectAttributes_NOSHR$$_TIFFerrorHandler")
	#endif
	;


	#if !HAVE_IEEEFP
	/* IEEE floting point handling */

	typedef struct ieeedouble {
	unsigned long mant2; /* fix NDR: full 8-byte swap */
	unsigned long mant : 20,
	exp : 11,
	sign : 1;
	} ieeedouble;
	typedef struct ieeefloat {
	unsigned long mant : 23,
	exp : 8,
	sign : 1;
	} ieeefloat;

	/*
	* NB: These are D_FLOAT's, not G_FLOAT's. A G_FLOAT is
	* simply a reverse-IEEE float/double.
	*/

	typedef struct {
	unsigned long mant1 : 7,
	exp : 8,
	sign : 1,
	mant2 : 16,
	mant3 : 16,
	mant4 : 16;
	} nativedouble;
	typedef struct {
	unsigned long mant1 : 7,
	exp : 8,
	sign : 1,
	mant2 : 16;
	} nativefloat;

	typedef union {
	ieeedouble ieee;
	nativedouble native;
	char b[8];
	uint32 l[2];
	double d;
	} double_t;

	typedef union {
	ieeefloat ieee;
	nativefloat native;
	char b[4];
	uint32 l;
	float f;
	} float_t;

	#if defined(VAXC) \|\| defined(DECC)
	#pragma inline(ieeetod,dtoieee)
	#endif

	/*
	* Convert an IEEE double precision number to native double precision.
	* The source is contained in two longwords, the second holding the sign,
	* exponent and the higher order bits of the mantissa, and the first
	* holding the rest of the mantissa as follows:
	* (Note: It is assumed that the number has been eight-byte swapped to
	* LSB first.)
	*
	* First longword:
	* 32 least significant bits of mantissa
	* Second longword:
	* 0-19: 20 most significant bits of mantissa
	* 20-30: exponent
	* 31: sign
	* The exponent is stored as excess 1023.
	* The most significant bit of the mantissa is implied 1, and not stored.
	* If the exponent and mantissa are zero, the number is zero.
	* If the exponent is 0 (i.e. -1023) and the mantissa is non-zero, it is an
	* unnormalized number with the most significant bit NOT implied.
	* If the exponent is 2047, the number is invalid, in case the mantissa is zero,
	* this means overflow (+/- depending of the sign bit), otherwise
	* it simply means invalid number.
	*
	* If the number is too large for the machine or was specified as overflow,
	* +/-HUGE_VAL is returned.
	*/
	INLINE static void
	ieeetod(double *dp)
	{
	double_t source;
	long sign,exp,mant;
	double dmant;

	source.ieee = ((double_t*)dp)->ieee;
	sign = source.ieee.sign;
	exp = source.ieee.exp;
	mant = source.ieee.mant;

	if (exp == 2047) {
	if (mant) /* Not a Number (NAN) */
	*dp = HUGE_VAL;
	else /* +/- infinity */
	*dp = (sign ? -HUGE_VAL : HUGE_VAL);
	return;
	}
	if (!exp) {
	if (!(mant \|\| source.ieee.mant2)) { /* zero */
	*dp=0;
	return;
	} else { /* Unnormalized number */
	/* NB: not -1023, the 1 bit is not implied */
	exp= -1022;
	}
	} else {
	mant \|= 1<<20;
	exp -= 1023;
	}
	dmant = (((double) mant) +
	((double) source.ieee.mant2) / (((double) (1<<16)) *
	((double) (1<<16)))) / (double) (1<<20);
	dmant = ldexp(dmant, exp);
	if (sign)
	dmant= -dmant;
	*dp = dmant;
	}

	INLINE static void
	dtoieee(double *dp)
	{
	double_t num;
	double x;
	int exp;

	num.d = *dp;
	if (!num.d) { /* Zero is just binary all zeros */
	num.l[0] = num.l[1] = 0;
	return;
	}

	if (num.d < 0) { /* Sign is encoded separately */
	num.d = -num.d;
	num.ieee.sign = 1;
	} else {
	num.ieee.sign = 0;
	}

	/* Now separate the absolute value into mantissa and exponent */
	x = frexp(num.d, &exp);

	/*
	* Handle cases where the value is outside the
	* range for IEEE floating point numbers.
	* (Overflow cannot happen on a VAX, but underflow
	* can happen for G float.)
	*/
	if (exp < -1022) { /* Unnormalized number */
	x = ldexp(x, -1023-exp);
	exp = 0;
	} else if (exp > 1023) { /* +/- infinity */
	x = 0;
	exp = 2047;
	} else { /* Get rid of most significant bit */
	x *= 2;
	x -= 1;
	exp += 1022; /* fix NDR: 1.0 -> x=0.5, exp=1 -> ieee.exp = 1023 */
	}
	num.ieee.exp = exp;

	x *= (double) (1<<20);
	num.ieee.mant = (long) x;
	x -= (double) num.ieee.mant;
	num.ieee.mant2 = (long) (x((double) (1<<16)(double) (1<<16)));

	if (!(num.ieee.mant \|\| num.ieee.exp \|\| num.ieee.mant2)) {
	/* Avoid negative zero */
	num.ieee.sign = 0;
	}
	((double_t*)dp)->ieee = num.ieee;
	}

	/*
	* Beware, these do not handle over/under-flow
	* during conversion from ieee to native format.
	*/
	#define NATIVE2IEEEFLOAT(fp) { \
	float_t t; \
	if (t.ieee.exp = (fp)->native.exp) \
	t.ieee.exp += -129 + 127; \
	t.ieee.sign = (fp)->native.sign; \
	t.ieee.mant = ((fp)->native.mant1<<16)\|(fp)->native.mant2; \
	*(fp) = t; \
	}
	#define IEEEFLOAT2NATIVE(fp) { \
	float_t t; int v = (fp)->ieee.exp; \
	if (v) v += -127 + 129; /* alter bias of exponent */\
	t.native.exp = v; /* implicit truncation of exponent */\
	t.native.sign = (fp)->ieee.sign; \
	v = (fp)->ieee.mant; \
	t.native.mant1 = v >> 16; \
	t.native.mant2 = v;\
	*(fp) = t; \
	}

	#define IEEEDOUBLE2NATIVE(dp) ieeetod(dp)

	#define NATIVE2IEEEDOUBLE(dp) dtoieee(dp)


	/*
	* These unions are used during floating point
	* conversions. The above macros define the
	* conversion operations.
	*/
	void
	TIFFCvtIEEEFloatToNative(TIFF* tif, u_int n, float* f)
	{
	float_t* fp = (float_t*) f;

	while (n-- > 0) {
	IEEEFLOAT2NATIVE(fp);
	fp++;
	}
	}

	void
	TIFFCvtNativeToIEEEFloat(TIFF* tif, u_int n, float* f)
	{
	float_t* fp = (float_t*) f;

	while (n-- > 0) {
	NATIVE2IEEEFLOAT(fp);
	fp++;
	}
	}
	void
	TIFFCvtIEEEDoubleToNative(TIFF* tif, u_int n, double* f)
	{
	double_t* fp = (double_t*) f;

	while (n-- > 0) {
	IEEEDOUBLE2NATIVE(fp);
	fp++;
	}
	}

	void
	TIFFCvtNativeToIEEEDouble(TIFF* tif, u_int n, double* f)
	{
	double_t* fp = (double_t*) f;

	while (n-- > 0) {
	NATIVE2IEEEDOUBLE(fp);
	fp++;
	}
	}
	#endif