/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* Copyright by The HDF Group. *
* All rights reserved. *
* *
* This file is part of HDF5. The full HDF5 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://www.hdfgroup.org/licenses. *
* If you do not have access to either file, you may request a copy from *
* help@hdfgroup.org. *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/*
* Programmer: Robb Matzke
* Friday, August 27, 1999
*/
#include "H5Zmodule.h" /* This source code file is part of the H5Z module */
#include "H5private.h" /* Generic Functions */
#include "H5Eprivate.h" /* Error handling */
#include "H5MMprivate.h" /* Memory management */
#include "H5Zpkg.h" /* Data filters */
#ifdef H5_HAVE_FILTER_DEFLATE
#if defined(H5_HAVE_ZLIB_H) && !defined(H5_ZLIB_HEADER)
#define H5_ZLIB_HEADER "zlib.h"
#endif
#if defined(H5_ZLIB_HEADER)
#include H5_ZLIB_HEADER /* "zlib.h" */
#endif
/* Local function prototypes */
static size_t H5Z__filter_deflate(unsigned flags, size_t cd_nelmts, const unsigned cd_values[], size_t nbytes,
size_t *buf_size, void **buf);
/* This message derives from H5Z */
const H5Z_class2_t H5Z_DEFLATE[1] = {{
H5Z_CLASS_T_VERS, /* H5Z_class_t version */
H5Z_FILTER_DEFLATE, /* Filter id number */
1, /* encoder_present flag (set to true) */
1, /* decoder_present flag (set to true) */
"deflate", /* Filter name for debugging */
NULL, /* The "can apply" callback */
NULL, /* The "set local" callback */
H5Z__filter_deflate, /* The actual filter function */
}};
#define H5Z_DEFLATE_SIZE_ADJUST(s) (HDceil(((double)(s)) * 1.001) + 12)
/*-------------------------------------------------------------------------
* Function: H5Z__filter_deflate
*
* Purpose: Implement an I/O filter around the 'deflate' algorithm in
* libz
*
* Return: Success: Size of buffer filtered
* Failure: 0
*
* Programmer: Robb Matzke
* Thursday, April 16, 1998
*
*-------------------------------------------------------------------------
*/
static size_t
H5Z__filter_deflate(unsigned flags, size_t cd_nelmts, const unsigned cd_values[], size_t nbytes,
size_t *buf_size, void **buf)
{
void *outbuf = NULL; /* Pointer to new buffer */
int status; /* Status from zlib operation */
size_t ret_value = 0; /* Return value */
FUNC_ENTER_PACKAGE
/* Sanity check */
HDassert(*buf_size > 0);
HDassert(buf);
HDassert(*buf);
/* Check arguments */
if (cd_nelmts != 1 || cd_values[0] > 9)
HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, 0, "invalid deflate aggression level")
if (flags & H5Z_FLAG_REVERSE) {
/* Input; uncompress */
z_stream z_strm; /* zlib parameters */
size_t nalloc = *buf_size; /* Number of bytes for output (compressed) buffer */
/* Allocate space for the compressed buffer */
if (NULL == (outbuf = H5MM_malloc(nalloc)))
HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "memory allocation failed for deflate uncompression")
/* Set the uncompression parameters */
HDmemset(&z_strm, 0, sizeof(z_strm));
z_strm.next_in = (Bytef *)*buf;
H5_CHECKED_ASSIGN(z_strm.avail_in, unsigned, nbytes, size_t);
z_strm.next_out = (Bytef *)outbuf;
H5_CHECKED_ASSIGN(z_strm.avail_out, unsigned, nalloc, size_t);
/* Initialize the uncompression routines */
if (Z_OK != inflateInit(&z_strm))
HGOTO_ERROR(H5E_PLINE, H5E_CANTINIT, 0, "inflateInit() failed")
/* Loop to uncompress the buffer */
do {
/* Uncompress some data */
status = inflate(&z_strm, Z_SYNC_FLUSH);
/* Check if we are done uncompressing data */
if (Z_STREAM_END == status)
break; /*done*/
/* Check for error */
if (Z_OK != status) {
(void)inflateEnd(&z_strm);
HGOTO_ERROR(H5E_PLINE, H5E_CANTINIT, 0, "inflate() failed")
}
else {
/* If we're not done and just ran out of buffer space, get more */
if (0 == z_strm.avail_out) {
void *new_outbuf; /* Pointer to new output buffer */
/* Allocate a buffer twice as big */
nalloc *= 2;
if (NULL == (new_outbuf = H5MM_realloc(outbuf, nalloc))) {
(void)inflateEnd(&z_strm);
HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0,
"memory allocation failed for deflate uncompression")
} /* end if */
outbuf = new_outbuf;
/* Update pointers to buffer for next set of uncompressed data */
z_strm.next_out = (unsigned char *)outbuf + z_strm.total_out;
z_strm.avail_out = (uInt)(nalloc - z_strm.total_out);
} /* end if */
} /* end else */
} while (status == Z_OK);
/* Free the input buffer */
H5MM_xfree(*buf);
/* Set return values */
*buf = outbuf;
outbuf = NULL;
*buf_size = nalloc;
ret_value = z_strm.total_out;
/* Finish uncompressing the stream */
(void)inflateEnd(&z_strm);
} /* end if */
else {
/*
* Output; compress but fail if the result would be larger than the
* input. The library doesn't provide in-place compression, so we
* must allocate a separate buffer for the result.
*/
const Bytef *z_src = (const Bytef *)(*buf);
Bytef *z_dst; /*destination buffer */
uLongf z_dst_nbytes = (uLongf)H5Z_DEFLATE_SIZE_ADJUST(nbytes);
uLong z_src_nbytes = (uLong)nbytes;
int aggression; /* Compression aggression setting */
/* Set the compression aggression level */
H5_CHECKED_ASSIGN(aggression, int, cd_values[0], unsigned);
/* Allocate output (compressed) buffer */
if (NULL == (outbuf = H5MM_malloc(z_dst_nbytes)))
HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "unable to allocate deflate destination buffer")
z_dst = (Bytef *)outbuf;
/* Perform compression from the source to the destination buffer */
status = compress2(z_dst, &z_dst_nbytes, z_src, z_src_nbytes, aggression);
/* Check for various zlib errors */
if (Z_BUF_ERROR == status)
HGOTO_ERROR(H5E_PLINE, H5E_CANTINIT, 0, "overflow")
else if (Z_MEM_ERROR == status)
HGOTO_ERROR(H5E_PLINE, H5E_CANTINIT, 0, "deflate memory error")
else if (Z_OK != status)
HGOTO_ERROR(H5E_PLINE, H5E_CANTINIT, 0, "other deflate error")
/* Successfully uncompressed the buffer */
else {
/* Free the input buffer */
H5MM_xfree(*buf);
/* Set return values */
*buf = outbuf;
outbuf = NULL;
*buf_size = nbytes;
ret_value = z_dst_nbytes;
} /* end else */
} /* end else */
done:
if (outbuf)
H5MM_xfree(outbuf);
FUNC_LEAVE_NOAPI(ret_value)
}
#endif /* H5_HAVE_FILTER_DEFLATE */