#ifndef _GIF_LIB_PRIVATE_H
#define _GIF_LIB_PRIVATE_H

#include "gif_lib.h"

#define PROGRAM_NAME		"GIFLIB"

#define LZ_MAX_CODE			4095	/* Biggest code possible in 12 bits. */
#define LZ_BITS				12

#define FLUSH_OUTPUT		4096    /* Impossible code, to signal flush. */
#define FIRST_CODE			4097    /* Impossible code, to signal first. */
#define NO_SUCH_CODE		4098    /* Impossible code, to signal empty. */

#define FILE_STATE_WRITE    0x01
#define FILE_STATE_SCREEN   0x02
#define FILE_STATE_IMAGE    0x04
#define FILE_STATE_READ     0x08

#define IS_READABLE(Private)    (Private->FileState & FILE_STATE_READ)
#define IS_WRITEABLE(Private)   (Private->FileState & FILE_STATE_WRITE)


typedef struct GifFilePrivateType {
    int FileState,
	FileHandle,							/* Where all this data goes to! */
	BitsPerPixel,						/* Bits per pixel (Codes uses at least this + 1). */
	ClearCode,							/* The CLEAR LZ code. */
	EOFCode,							/* The EOF LZ code. */
	RunningCode,						/* The next code algorithm can generate. */
	RunningBits,						/* The number of bits required to represent RunningCode. */
	MaxCode1,							/* 1 bigger than max. possible code, in RunningBits bits. */
	LastCode,							/* The code before the current code. */
	CrntCode,							/* Current algorithm code. */
	StackPtr,							/* For character stack (see below). */
	CrntShiftState;						/* Number of bits in CrntShiftDWord. */
    unsigned long CrntShiftDWord;		/* For bytes decomposition into codes. */
    unsigned long PixelCount;		    /* Number of pixels in image. */
    FILE *File;							/* File as stream. */
    InputFunc Read;						/* function to read gif input (TVT) */
    OutputFunc Write;					/* function to write gif output (MRB) */
    GifByteType Buf[256];				/* Compressed input is buffered here. */
    GifByteType Stack[LZ_MAX_CODE];		/* Decoded pixels are stacked here. */
    GifByteType Suffix[LZ_MAX_CODE+1];  /* So we can trace the codes. */
    unsigned int Prefix[LZ_MAX_CODE+1];
} GifFilePrivateType;

extern int _GifError;

#ifdef SYSV
static char *VersionStr =
        "Gif library module,\t\tEric S. Raymond\n\
	(C) Copyright 1997 Eric S. Raymond\n";
#else
static char *VersionStr =
	PROGRAM_NAME
	"	IBMPC "
	GIF_LIB_VERSION
	"	Eric S. Raymond,	"
	__DATE__ ",   " __TIME__ "\n"
	"(C) Copyright 1997 Eric S. Raymond\n";
#endif /* SYSV */

#endif /* _GIF_LIB_PRIVATE_H */