static PyObject *
compress_helper(void * input, size_t nbytes, size_t typesize,
int clevel, int shuffle, char *cname){
int cbytes;
PyObject *output = NULL;
/* Alloc memory for compression */
if (!(output = PyBytes_FromStringAndSize(NULL, nbytes+BLOSC_MAX_OVERHEAD)))
return NULL;
/* Select compressor */
if (blosc_set_compressor(cname) < 0) {
/* The compressor is not available (should never happen here) */
blosc_error(-1, "compressor not available");
return NULL;
}
/* Compress */
cbytes = blosc_compress(clevel, shuffle, typesize, nbytes,
input, PyBytes_AS_STRING(output),
nbytes+BLOSC_MAX_OVERHEAD);
if (cbytes < 0) {
blosc_error(cbytes, "while compressing data");
Py_XDECREF(output);
return NULL;
}
/* Attempt to resize, if it's much smaller, a copy is required. */
if (_PyBytes_Resize(&output, cbytes) < 0){
/* the memory exception will have been set, hopefully */
return NULL;
}
return output;
}
/* Read blosc header from input and fetch the uncompressed size into nbytes.
* Also makes sure that value of the compressed bytes from the header is the
* same as the cbytes provided by the input.
*
* Returns 1 on success and 0 on failure with a Python exception set.
*
* */
static int
get_nbytes(void * input, size_t cbytes, size_t * nbytes)
{
size_t cbytes2, blocksize;
/* Get the length of the uncompressed buffer */
blosc_cbuffer_sizes(input, nbytes, &cbytes2, &blocksize);
if ((size_t)cbytes != cbytes2) {
blosc_error((int)cbytes,
": not a Blosc buffer or header info is corrupted");
return 0;
}
return 1;
}
/* Decompress nbytes from input into output.
*
* Returns 1 on success and 0 on failure with a Python exception set.
*
* */
static int
decompress_helper(void * input, size_t nbytes, void * output)
{
int err;
/* Do the decompression */
err = blosc_decompress(input, output, nbytes);
if (err < 0 || err != (int)nbytes) {
blosc_error(err, "while decompressing data");
return 0;
}
return 1;
}
/* Decompress nbytes from input into output.
*
* Returns 1 on success and 0 on failure with a Python exception set.
*
* */
static int
decompress_helper(void * input, size_t nbytes, void * output)
{
int err, nthreads;
PyThreadState *_save = NULL;
/* Do the decompression */
// int blosc_decompress_ctx(const void *src, void *dest, size_t destsize,
// int numinternalthreads)
if( RELEASEGIL )
{
_save = PyEval_SaveThread();
nthreads = blosc_get_nthreads();
err = blosc_decompress_ctx(input, output, nbytes, nthreads);
PyEval_RestoreThread(_save);
_save = NULL;
}
else
{ // Run while holding the GIL
err = blosc_decompress(input, output, nbytes);
}
if (err < 0) {
blosc_error(err, "while decompressing data");
return 0;
}
else if (err != (int)nbytes) {
PyErr_Format(BloscError,
"expected %d bytes of decompressed data, got %d",
(int) nbytes,
err);
return 0;
}
return 1;
}
static PyObject *
compress_helper(void * input, size_t nbytes, size_t typesize,
int clevel, int shuffle, char *cname){
int cbytes, blocksize, nthreads;
PyObject *output;
char *output_ptr;
PyThreadState *_save = NULL;
/* Alloc memory for compression */
if (!(output = PyBytes_FromStringAndSize(NULL, nbytes+BLOSC_MAX_OVERHEAD)))
return NULL;
/* Select compressor */
if (blosc_set_compressor(cname) < 0) {
/* The compressor is not available (should never happen here) */
blosc_error(-1, "compressor not available");
Py_DECREF(output);
return NULL;
}
/* Compress */
// This macro probably doesn't require the Python interpreter but let's leave it outside for safety
output_ptr = PyBytes_AS_STRING(output);
if( RELEASEGIL )
{
// Run with GIL released, tiny overhead penalty from this (although it
// may be significant for smaller chunks.)
_save = PyEval_SaveThread();
blocksize = blosc_get_blocksize();
// if blocksize==0, blosc_compress_ctx will try to auto-optimize it.
nthreads = blosc_get_nthreads();
cbytes = blosc_compress_ctx(clevel, shuffle, typesize, nbytes,
input, output_ptr, nbytes+BLOSC_MAX_OVERHEAD,
cname, blocksize, nthreads);
PyEval_RestoreThread(_save);
_save = NULL;
}
else
{ // Hold onto the Python GIL while compressing
cbytes = blosc_compress(clevel, shuffle, typesize, nbytes,
input, output_ptr,
nbytes+BLOSC_MAX_OVERHEAD);
}
if (cbytes < 0) {
blosc_error(cbytes, "while compressing data");
Py_DECREF(output);
return NULL;
}
/* Attempt to resize, if it's much smaller, a copy is required. */
if (_PyBytes_Resize(&output, cbytes) < 0){
/* the memory exception will have been set, hopefully */
Py_DECREF(output);
return NULL;
}
return output;
}