60 lines
2.4 KiB
C
60 lines
2.4 KiB
C
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/****************************************************************************
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gif_lib_private.h - internal giflib routines and structures
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****************************************************************************/
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#ifndef _GIF_LIB_PRIVATE_H
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#define _GIF_LIB_PRIVATE_H
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#include "gif_lib.h"
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#include "gif_hash.h"
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#define EXTENSION_INTRODUCER 0x21
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#define DESCRIPTOR_INTRODUCER 0x2c
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#define TERMINATOR_INTRODUCER 0x3b
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#define LZ_MAX_CODE 4095 /* Biggest code possible in 12 bits. */
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#define LZ_BITS 12
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#define FLUSH_OUTPUT 4096 /* Impossible code, to signal flush. */
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#define FIRST_CODE 4097 /* Impossible code, to signal first. */
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#define NO_SUCH_CODE 4098 /* Impossible code, to signal empty. */
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#define FILE_STATE_WRITE 0x01
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#define FILE_STATE_SCREEN 0x02
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#define FILE_STATE_IMAGE 0x04
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#define FILE_STATE_READ 0x08
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#define IS_READABLE(Private) (Private->FileState & FILE_STATE_READ)
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#define IS_WRITEABLE(Private) (Private->FileState & FILE_STATE_WRITE)
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typedef struct GifFilePrivateType {
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GifWord FileState, FileHandle, /* Where all this data goes to! */
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BitsPerPixel, /* Bits per pixel (Codes uses at least this + 1). */
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ClearCode, /* The CLEAR LZ code. */
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EOFCode, /* The EOF LZ code. */
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RunningCode, /* The next code algorithm can generate. */
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RunningBits, /* The number of bits required to represent RunningCode. */
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MaxCode1, /* 1 bigger than max. possible code, in RunningBits bits. */
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LastCode, /* The code before the current code. */
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CrntCode, /* Current algorithm code. */
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StackPtr, /* For character stack (see below). */
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CrntShiftState; /* Number of bits in CrntShiftDWord. */
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unsigned long CrntShiftDWord; /* For bytes decomposition into codes. */
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unsigned long PixelCount; /* Number of pixels in image. */
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FILE *File; /* File as stream. */
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InputFunc Read; /* function to read gif input (TVT) */
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OutputFunc Write; /* function to write gif output (MRB) */
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GifByteType Buf[256]; /* Compressed input is buffered here. */
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GifByteType Stack[LZ_MAX_CODE]; /* Decoded pixels are stacked here. */
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GifByteType Suffix[LZ_MAX_CODE + 1]; /* So we can trace the codes. */
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GifPrefixType Prefix[LZ_MAX_CODE + 1];
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GifHashTableType *HashTable;
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bool gif89;
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} GifFilePrivateType;
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#endif /* _GIF_LIB_PRIVATE_H */
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/* end */
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