Ejemplo n.º 1
0
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;
}
Ejemplo n.º 2
0
/*  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;
}
Ejemplo n.º 3
0
/*  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;
}
Ejemplo n.º 4
0
/*  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;
}
Ejemplo n.º 5
0
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;
}