mirror of
https://github.com/Unidata/netcdf-c.git
synced 2024-11-27 07:30:33 +08:00
d07c05b58f
re: issue https://github.com/Unidata/netcdf-c/issues/1156 Starting with HDF5 version 1.10.x, the plugin code MUST be careful when using the standard *malloc()*, *realloc()*, and *free()* function. In the event that the code is allocating, reallocating, or free'ing memory that either came from -- or will be exported to -- the calling HDF5 library, then one MUST use the corresponding HDF5 functions *H5allocate_memory()*, *H5resize_memory()*, *H5free_memory()* [5] to avoid memory failures. Additionally, if your filter code leaks memory, then the HDF5 library generates a failure something like this. ```` H5MM.c:232: H5MM_final_sanity_check: Assertion `0 == H5MM_curr_alloc_bytes_s' failed. ```` This PR modifies the code in the plugins directory to conform to these new requirements. This raises a question about the libhdf5 code where this same problem may occur. We need to scan especially nc4hdf.c to look for this problem.
105 lines
2.9 KiB
C
105 lines
2.9 KiB
C
#include <sys/types.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <assert.h>
|
|
#include <stdio.h>
|
|
#include <hdf5.h>
|
|
/* Older versions of the hdf library may define H5PL_type_t here */
|
|
#include <H5PLextern.h>
|
|
#include "xxxx.h"
|
|
|
|
/*
|
|
Provide a textual template (not a C++ template)
|
|
from which one can construct a new filter.
|
|
The filter "name is marked with "XXXX" or "xxxx"
|
|
|
|
*/
|
|
|
|
const H5Z_class2_t H5Z_XXXX[1] = {{
|
|
H5Z_CLASS_T_VERS, /* H5Z_class_t version */
|
|
(H5Z_filter_t)H5Z_FILTER_XXXX, /* Filter id number */
|
|
1, /* encoder_present flag (set to true) */
|
|
1, /* decoder_present flag (set to true) */
|
|
"xxxx", /* Filter name for debugging */
|
|
NULL, /* The "can apply" callback */
|
|
NULL, /* The "set local" callback */
|
|
(H5Z_func_t)H5Z_filter_xxxx, /* The actual filter function */
|
|
}};
|
|
|
|
/* External Discovery Functions */
|
|
H5PL_type_t
|
|
H5PLget_plugin_type(void)
|
|
{
|
|
return H5PL_TYPE_FILTER;
|
|
}
|
|
|
|
const void*
|
|
H5PLget_plugin_info(void)
|
|
{
|
|
return H5Z_XXXX;
|
|
}
|
|
|
|
size_t H5Z_filter_xxxx(unsigned int flags, size_t cd_nelmts,
|
|
const unsigned int cd_values[], size_t nbytes,
|
|
size_t *buf_size, void **buf);
|
|
|
|
|
|
size_t H5Z_filter_xxxx(unsigned int flags, size_t cd_nelmts,
|
|
const unsigned int cd_values[], size_t nbytes,
|
|
size_t *buf_size, void **buf)
|
|
{
|
|
char *outbuf = NULL;
|
|
size_t outbuflen, outdatalen;
|
|
int ret;
|
|
|
|
if (flags & H5Z_FLAG_REVERSE) {
|
|
|
|
/** Decompress data.
|
|
**
|
|
** This process is troublesome since the size of uncompressed data
|
|
** is unknown, so the low-level interface must be used.
|
|
** Data is decompressed to the output buffer (which is sized
|
|
** for the average case); if it gets full, its size is doubled
|
|
** and decompression continues. This avoids repeatedly trying to
|
|
** decompress the whole block, which could be really inefficient.
|
|
**/
|
|
|
|
char *newbuf = NULL;
|
|
size_t newbuflen;
|
|
|
|
} else {
|
|
|
|
/** Compress data.
|
|
**
|
|
** This is quite simple, since the size of compressed data in the worst
|
|
** case is known and it is not much bigger than the size of uncompressed
|
|
** data. This allows us to use the simplified one-shot interface to
|
|
** compression.
|
|
**/
|
|
|
|
unsigned int odatalen; /* maybe not the same size as outdatalen */
|
|
|
|
/* Prepare the output buffer. */
|
|
outbuflen = M; /* worst case */
|
|
outbuf = H5allocate_memory(outbuflen,0);
|
|
if (outbuf == NULL) {
|
|
fprintf(stderr, "memory allocation failed for xxxx compression\n");
|
|
goto cleanupAndFail;
|
|
}
|
|
|
|
/* Compress data. */
|
|
|
|
}
|
|
|
|
/* Always replace the input buffer with the output buffer. */
|
|
H5free_memory(*buf);
|
|
*buf = outbuf;
|
|
*buf_size = outbuflen;
|
|
return outdatalen;
|
|
|
|
cleanupAndFail:
|
|
if (outbuf)
|
|
H5free_memory(outbuf);
|
|
return 0;
|
|
}
|