tiffcomp.h

一个国人自己实现图像库的程序（有参考价值）

/* $Header: /cvsroot/osrs/libtiff/libtiff/tiffcomp.h,v 1.3 2000/11/13 14:23:53 warmerda Exp $ */

/*
 * Copyright (c) 1990-1997 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.
 */

#ifndef _COMPAT_
#define	_COMPAT_
/*
 * This file contains a hodgepodge of definitions and
 * declarations that are needed to provide compatibility
 * between the native system and the base implementation
 * that the library assumes.
 *
 * NB: This file is a mess.
 */

/*
 * Setup basic type definitions and function declaratations.
 */

/*
 * Simplify Acorn RISC OS identifier (to avoid confusion with Acorn RISC iX
 * and with defunct Unix Risc OS)
 * No need to specify __arm - hey, Acorn might port the OS, no problem here!
 */
#ifdef __acornriscos
#undef __acornriscos
#endif
#if defined(__acorn) && defined(__riscos)
#define __acornriscos
#endif

#if defined(__MWERKS__) || defined(THINK_C)
#include <unix.h>
#include <math.h>
#endif

#include <stdio.h>

#if defined(__PPCC__) || defined(__SC__) || defined(__MRC__)
#include <types.h>
#elif !defined(__MWERKS__) && !defined(THINK_C) && !defined(__acornriscos) && !defined(applec)
#include <sys/types.h>
#endif

#if defined(VMS)
#include <file.h>
#include <unixio.h>
#elif !defined(__acornriscos)
#include <fcntl.h>
#endif

/*
 * This maze of checks controls defines or not the
 * target system has BSD-style typdedefs declared in
 * an include file and/or whether or not to include
 * <unistd.h> to get the SEEK_* definitions.  Some
 * additional includes are also done to pull in the
 * appropriate definitions we're looking for.
 */
#if defined(__MWERKS__) || defined(THINK_C) || defined(__PPCC__) || defined(__SC__) || defined(__MRC__)
#include <stdlib.h>
#define	BSDTYPES
#define	HAVE_UNISTD_H	0
#elif (defined(_WINDOWS) || defined(__WIN32__) || defined(_Windows) || defined(_WIN32)) && !defined(unix)
#define	BSDTYPES
#elif defined(OS2_16) || defined(OS2_32)
#define	BSDTYPES
#elif defined(__acornriscos)
#include <stdlib.h>
#define	BSDTYPES
#define	HAVE_UNISTD_H	0
#elif defined(VMS)
#define	HAVE_UNISTD_H	0
#else
#define	HAVE_UNISTD_H	1
#endif

/*
 * The library uses the ANSI C/POSIX SEEK_*
 * definitions that should be defined in unistd.h
 * (except on system where they are in stdio.h and
 * there is no unistd.h).
 */
#if !defined(SEEK_SET) && HAVE_UNISTD_H
#include <unistd.h>
#endif

/*
 * The library uses memset, memcpy, and memcmp.
 * ANSI C and System V define these in string.h.
 */
#include <string.h>

/*
 * The BSD typedefs are used throughout the library.
 * If your system doesn't have them in <sys/types.h>,
 * then define BSDTYPES in your Makefile.
 */
#if defined(BSDTYPES)
typedef	unsigned char u_char;
typedef	unsigned short u_short;
typedef	unsigned int u_int;
typedef	unsigned long u_long;
#endif

/*
 * dblparam_t is the type that a double precision
 * floating point value will have on the parameter
 * stack (when coerced by the compiler).
 */
/* Note: on MacPowerPC "extended" is undefined. So only use it for 68K-Macs */
#if defined(__SC__) || defined(THINK_C)
typedef extended dblparam_t;
#else
typedef double dblparam_t;
#endif

/*
 * If your compiler supports inline functions, then
 * set INLINE appropriately to get the known hotspots
 * in the library expanded inline.
 */
#if defined(__GNUC__)
#if defined(__STRICT_ANSI__)
#define	INLINE	__inline__
#else
#define	INLINE	inline
#endif
#else /* !__GNUC__ */
#define	INLINE
#endif

/*
 * GLOBALDATA is a macro that is used to define global variables
 * private to the library.  We use this indirection to hide
 * brain-damage in VAXC (and GCC) under VAX/VMS.  In these
 * environments the macro places the variable in a non-shareable
 * program section, which ought to be done by default (sigh!)
 *
 * Apparently DEC are aware of the problem as this behaviour is the
 * default under VMS on AXP.
 *
 * The GNU C variant is untested.
 */
#if defined(VAX) && defined(VMS)
#if defined(VAXC)
#define GLOBALDATA(TYPE,NAME)	extern noshare TYPE NAME
#endif
#if defined(__GNUC__)
#define GLOBALDATA(TYPE,NAME)	extern TYPE NAME \
	asm("_$$PsectAttributes_NOSHR$$" #NAME)
#endif
#else	/* !VAX/VMS */
#define GLOBALDATA(TYPE,NAME)	extern TYPE NAME
#endif

#if defined(__acornriscos)
/*
 * osfcn.h is part of C++Lib on Acorn C/C++, and as such can't be used
 * on C alone. For that reason, the relevant functions are
 * implemented in tif_acorn.c, and the elements from the header
 * file are included here.
 */
#if defined(__cplusplus)
#include <osfcn.h>
#else
#define	O_RDONLY	0
#define	O_WRONLY	1
#define	O_RDWR		2
#define	O_APPEND	8
#define	O_CREAT		0x200
#define	O_TRUNC		0x400
typedef long off_t;
extern int open(const char *name, int flags, int mode);
extern int close(int fd);
extern int write(int fd, const char *buf, int nbytes);
extern int read(int fd, char *buf, int nbytes);
extern off_t lseek(int fd, off_t offset, int whence);
extern int creat(const char *path, int mode);
#endif /* __cplusplus */
#endif /* __acornriscos */

/* Bit and byte order, the default is MSB to LSB */
#ifdef VMS
#undef HOST_FILLORDER
#undef HOST_BIGENDIAN
#define HOST_FILLORDER FILLORDER_LSB2MSB
#define HOST_BIGENDIAN	0
#endif


#endif /* _COMPAT_ */