summaryrefslogtreecommitdiffstats
path: root/src/H5Zshuffle.c
blob: 4d5f4563adc08e534d43e94f0e73ecf90121b949 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * Copyright by the Board of Trustees of the University of Illinois.         *
 * 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://support.hdfgroup.org/ftp/HDF5/releases.  *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#define H5Z_PACKAGE /*suppress error about including H5Zpkg	  */

#include "H5private.h"   /* Generic Functions			*/
#include "H5Eprivate.h"  /* Error handling		  	*/
#include "H5Iprivate.h"  /* IDs			  		*/
#include "H5MMprivate.h" /* Memory management			*/
#include "H5Pprivate.h"  /* Property lists                       */
#include "H5Tprivate.h"  /* Datatypes         			*/
#include "H5Zpkg.h"      /* Data filters				*/

/* Local function prototypes */
static herr_t H5Z_set_local_shuffle(hid_t dcpl_id, hid_t type_id, hid_t space_id);
static size_t H5Z_filter_shuffle(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_SHUFFLE[1] = {{
    H5Z_CLASS_T_VERS,      /* H5Z_class_t version */
    H5Z_FILTER_SHUFFLE,    /* Filter id number		*/
    1,                     /* encoder_present flag (set to true) */
    1,                     /* decoder_present flag (set to true) */
    "shuffle",             /* Filter name for debugging	*/
    NULL,                  /* The "can apply" callback     */
    H5Z_set_local_shuffle, /* The "set local" callback     */
    H5Z_filter_shuffle,    /* The actual filter function	*/
}};

/* Local macros */
#define H5Z_SHUFFLE_PARM_SIZE 0 /* "Local" parameter for shuffling size */

/*-------------------------------------------------------------------------
 * Function:	H5Z_set_local_shuffle
 *
 * Purpose:	Set the "local" dataset parameter for data shuffling to be
 *              the size of the datatype.
 *
 * Return:	Success: Non-negative
 *		Failure: Negative
 *
 * Programmer:	Quincey Koziol
 *              Monday, April  7, 2003
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5Z_set_local_shuffle(hid_t dcpl_id, hid_t type_id, hid_t H5_ATTR_UNUSED space_id)
{
    H5P_genplist_t *dcpl_plist;                          /* Property list pointer */
    const H5T_t *   type;                                /* Datatype */
    unsigned        flags;                               /* Filter flags */
    size_t          cd_nelmts = H5Z_SHUFFLE_USER_NPARMS; /* Number of filter parameters */
    unsigned        cd_values[H5Z_SHUFFLE_TOTAL_NPARMS]; /* Filter parameters */
    herr_t          ret_value = SUCCEED;                 /* Return value */

    FUNC_ENTER_NOAPI(FAIL)

    /* Get the plist structure */
    if (NULL == (dcpl_plist = H5P_object_verify(dcpl_id, H5P_DATASET_CREATE)))
        HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID")

    /* Get datatype */
    if (NULL == (type = (const H5T_t *)H5I_object_verify(type_id, H5I_DATATYPE)))
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a datatype")

    /* Get the filter's current parameters */
    if (H5P_get_filter_by_id(dcpl_plist, H5Z_FILTER_SHUFFLE, &flags, &cd_nelmts, cd_values, (size_t)0, NULL,
                             NULL) < 0)
        HGOTO_ERROR(H5E_PLINE, H5E_CANTGET, FAIL, "can't get shuffle parameters")

    /* Set "local" parameter for this dataset */
    if ((cd_values[H5Z_SHUFFLE_PARM_SIZE] = (unsigned)H5T_get_size(type)) == 0)
        HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "bad datatype size")

    /* Modify the filter's parameters for this dataset */
    if (H5P_modify_filter(dcpl_plist, H5Z_FILTER_SHUFFLE, flags, (size_t)H5Z_SHUFFLE_TOTAL_NPARMS,
                          cd_values) < 0)
        HGOTO_ERROR(H5E_PLINE, H5E_CANTSET, FAIL, "can't set local shuffle parameters")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5Z_set_local_shuffle() */

/*-------------------------------------------------------------------------
 * Function:	H5Z_filter_shuffle
 *
 * Purpose:	Implement an I/O filter which "de-interlaces" a block of data
 *              by putting all the bytes in a byte-position for each element
 *              together in the block.  For example, for 4-byte elements stored
 *              as: 012301230123, shuffling will store them as: 000111222333
 *              Usually, the bytes in each byte position are more related to
 *              each other and putting them together will increase compression.
 *
 * Return:	Success: Size of buffer filtered
 *		Failure: 0
 *
 * Programmer:	Kent Yang
 *              Wednesday, November 13, 2002
 *
 *-------------------------------------------------------------------------
 */
static size_t
H5Z_filter_shuffle(unsigned flags, size_t cd_nelmts, const unsigned cd_values[], size_t nbytes,
                   size_t *buf_size, void **buf)
{
    void *         dest  = NULL;  /* Buffer to deposit [un]shuffled bytes into */
    unsigned char *_src  = NULL;  /* Alias for source buffer */
    unsigned char *_dest = NULL;  /* Alias for destination buffer */
    unsigned       bytesoftype;   /* Number of bytes per element */
    size_t         numofelements; /* Number of elements in buffer */
    size_t         i;             /* Local index variables */
#ifdef NO_DUFFS_DEVICE
    size_t j;             /* Local index variable */
#endif                    /* NO_DUFFS_DEVICE */
    size_t leftover;      /* Extra bytes at end of buffer */
    size_t ret_value = 0; /* Return value */

    FUNC_ENTER_NOAPI(0)

    /* Check arguments */
    if (cd_nelmts != H5Z_SHUFFLE_TOTAL_NPARMS || cd_values[H5Z_SHUFFLE_PARM_SIZE] == 0)
        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, 0, "invalid shuffle parameters")

    /* Get the number of bytes per element from the parameter block */
    bytesoftype = cd_values[H5Z_SHUFFLE_PARM_SIZE];

    /* Compute the number of elements in buffer */
    numofelements = nbytes / bytesoftype;

    /* Don't do anything for 1-byte elements, or "fractional" elements */
    if (bytesoftype > 1 && numofelements > 1) {
        /* Compute the leftover bytes if there are any */
        leftover = nbytes % bytesoftype;

        /* Allocate the destination buffer */
        if (NULL == (dest = H5MM_malloc(nbytes)))
            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "memory allocation failed for shuffle buffer")

        if (flags & H5Z_FLAG_REVERSE) {
            /* Get the pointer to the source buffer */
            _src = (unsigned char *)(*buf);

            /* Input; unshuffle */
            for (i = 0; i < bytesoftype; i++) {
                _dest = ((unsigned char *)dest) + i;
#define DUFF_GUTS                                                                                            \
    *_dest = *_src++;                                                                                        \
    _dest += bytesoftype;
#ifdef NO_DUFFS_DEVICE
                j = numofelements;
                while (j > 0) {
                    DUFF_GUTS;

                    j--;
                } /* end for */
#else             /* NO_DUFFS_DEVICE */
                {
                    size_t duffs_index; /* Counting index for Duff's device */

                    duffs_index = (numofelements + 7) / 8;
                    switch (numofelements % 8) {
                        default:
                            HDassert(0 && "This Should never be executed!");
                            break;
                        case 0:
                            do {
                                DUFF_GUTS
                                case 7:
                                    DUFF_GUTS
                                case 6:
                                    DUFF_GUTS
                                case 5:
                                    DUFF_GUTS
                                case 4:
                                    DUFF_GUTS
                                case 3:
                                    DUFF_GUTS
                                case 2:
                                    DUFF_GUTS
                                case 1:
                                    DUFF_GUTS
                            } while (--duffs_index > 0);
                    } /* end switch */
                }
#endif            /* NO_DUFFS_DEVICE */
#undef DUFF_GUTS
            } /* end for */

            /* Add leftover to the end of data */
            if (leftover > 0) {
                /* Adjust back to end of shuffled bytes */
                _dest -= (bytesoftype - 1); /*lint !e794 _dest is initialized */
                HDmemcpy((void *)_dest, (void *)_src, leftover);
            }
        } /* end if */
        else {
            /* Get the pointer to the destination buffer */
            _dest = (unsigned char *)dest;

            /* Output; shuffle */
            for (i = 0; i < bytesoftype; i++) {
                _src = ((unsigned char *)(*buf)) + i;
#define DUFF_GUTS                                                                                            \
    *_dest++ = *_src;                                                                                        \
    _src += bytesoftype;
#ifdef NO_DUFFS_DEVICE
                j = numofelements;
                while (j > 0) {
                    DUFF_GUTS;

                    j--;
                } /* end for */
#else             /* NO_DUFFS_DEVICE */
                {
                    size_t duffs_index; /* Counting index for Duff's device */

                    duffs_index = (numofelements + 7) / 8;
                    switch (numofelements % 8) {
                        default:
                            HDassert(0 && "This Should never be executed!");
                            break;
                        case 0:
                            do {
                                DUFF_GUTS
                                case 7:
                                    DUFF_GUTS
                                case 6:
                                    DUFF_GUTS
                                case 5:
                                    DUFF_GUTS
                                case 4:
                                    DUFF_GUTS
                                case 3:
                                    DUFF_GUTS
                                case 2:
                                    DUFF_GUTS
                                case 1:
                                    DUFF_GUTS
                            } while (--duffs_index > 0);
                    } /* end switch */
                }
#endif            /* NO_DUFFS_DEVICE */
#undef DUFF_GUTS
            } /* end for */

            /* Add leftover to the end of data */
            if (leftover > 0) {
                /* Adjust back to end of shuffled bytes */
                _src -= (bytesoftype - 1); /*lint !e794 _src is initialized */
                HDmemcpy((void *)_dest, (void *)_src, leftover);
            }
        } /* end else */

        /* Free the input buffer */
        H5MM_xfree(*buf);

        /* Set the buffer information to return */
        *buf      = dest;
        *buf_size = nbytes;
    } /* end else */

    /* Set the return value */
    ret_value = nbytes;

done:
    FUNC_LEAVE_NOAPI(ret_value)
}