cdeflate.h

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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * Copyright by the Board of Trustees of the University of Illinois.         *
 * All rights reserved.                                                      *
 *                                                                           *
 * This file is part of HDF.  The full HDF copyright notice, including       *
 * terms governing use, modification, and redistribution, is contained in    *
 * the COPYING file, which can be found at the root of the source code       *
 * distribution tree, or in https://support.hdfgroup.org/ftp/HDF/releases/.  *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

 /* $Id$ */

 /*-----------------------------------------------------------------------------
 * File:    cdeflate.h
 * Purpose: Header file for gzip 'deflate' encoding information.
 * Dependencies: should only be included from hcompi.h
 * Invokes: none
 * Contents: Structures & definitions for gzip 'deflate' encoding.
 * Structure definitions:
 * Constant definitions:
 *---------------------------------------------------------------------------*/

/* avoid re-inclusion */
#ifndef __CDEFLATE_H
#define __CDEFLATE_H

/* Get the gzip 'deflate' header */
#define intf zintf
#include "zlib.h"
#undef zintf

#if defined c_plusplus || defined __cplusplus
extern      "C"
{
#endif                          /* c_plusplus || __cplusplus */

/*
   ** from cdeflate.c
 */

    extern int32 HCPcdeflate_stread
                (accrec_t * rec);

    extern int32 HCPcdeflate_stwrite
                (accrec_t * rec);

    extern int32 HCPcdeflate_seek
                (accrec_t * access_rec, int32 offset, int origin);

    extern int32 HCPcdeflate_inquire
                (accrec_t * access_rec, int32 *pfile_id, uint16 *ptag, uint16 *pref,
               int32 *plength, int32 *poffset, int32 *pposn, int16 *paccess,
                 int16 *pspecial);

    extern int32 HCPcdeflate_read
                (accrec_t * access_rec, int32 length, void * data);

    extern int32 HCPcdeflate_write
                (accrec_t * access_rec, int32 length, const void * data);

    extern intn HCPcdeflate_endaccess
                (accrec_t * access_rec);

#if defined c_plusplus || defined __cplusplus
}
#endif                          /* c_plusplus || __cplusplus */

/* Define the [default] size of the buffer to interact with the file. */
#define DEFLATE_BUF_SIZE    4096
#define DEFLATE_TMP_BUF_SIZE        16384

/* gzip [en|de]coding information */
typedef struct
{
    intn        deflate_level;  /* how hard to try to compress this data */
    int32       offset;         /* offset in the de-compressed array */
    intn        acc_init;       /* is access mode initialized? */
    int16       acc_mode;       /* access mode desired */
    void *       io_buf;         /* buffer for I/O with the file */
    z_stream    deflate_context;    /* pointer to the deflation context for each byte in the element */
}
comp_coder_deflate_info_t;

#ifndef CDEFLATE_MASTER
extern funclist_t cdeflate_funcs;   /* functions to perform gzip encoding */
#else
funclist_t  cdeflate_funcs =
{                               /* functions to perform gzip encoding */
    HCPcdeflate_stread,
    HCPcdeflate_stwrite,
    HCPcdeflate_seek,
    HCPcdeflate_inquire,
    HCPcdeflate_read,
    HCPcdeflate_write,
    HCPcdeflate_endaccess
};
#endif

#endif /* __CDEFLATE_H */