summaryrefslogtreecommitdiffstats
path: root/src/H5PLint.c
blob: 73be42af933b3b26eabbdafadfaf3af1904dab1e (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
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 * Purpose: Internal routines for managing plugins.
 *
 */

/****************/
/* Module Setup */
/****************/

#include "H5PLmodule.h" /* This source code file is part of the H5PL module */

/***********/
/* Headers */
/***********/
#include "H5private.h"   /* Generic Functions            */
#include "H5Eprivate.h"  /* Error handling               */
#include "H5MMprivate.h" /* Memory management            */
#include "H5PLpkg.h"     /* Plugin                       */
#include "H5Zprivate.h"  /* Filter pipeline              */

/****************/
/* Local Macros */
/****************/

/******************/
/* Local Typedefs */
/******************/

/********************/
/* Local Prototypes */
/********************/

/*********************/
/* Package Variables */
/*********************/

/*****************************/
/* Library Private Variables */
/*****************************/

/*******************/
/* Local Variables */
/*******************/

/* Bitmask that controls whether classes of plugins
 * (e.g.: filters, VOL drivers) can be loaded.
 */
static unsigned int H5PL_plugin_control_mask_g = H5PL_ALL_PLUGIN;

/* This flag will be set to FALSE if the HDF5_PLUGIN_PRELOAD
 * environment variable was set to H5PL_NO_PLUGIN at
 * package initialization.
 */
static hbool_t H5PL_allow_plugins_g = TRUE;

/*-------------------------------------------------------------------------
 * Function:    H5PL__get_plugin_control_mask
 *
 * Purpose:     Gets the internal plugin control mask value.
 *
 * Return:      SUCCEED/FAIL
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5PL__get_plugin_control_mask(unsigned int *mask /*out*/)
{
    herr_t ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE_NOERR

    /* Check args - Just assert on package functions */
    assert(mask);

    /* Return the mask */
    *mask = H5PL_plugin_control_mask_g;

    FUNC_LEAVE_NOAPI(ret_value)

} /* end H5PL__get_plugin_control_mask() */

/*-------------------------------------------------------------------------
 * Function:    H5PL__set_plugin_control_mask
 *
 * Purpose:     Sets the internal plugin control mask value.
 *
 * Return:      SUCCEED/FAIL
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5PL__set_plugin_control_mask(unsigned int mask)
{
    herr_t ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE_NOERR

    /* Only allow setting this if plugins have not been disabled.
     * XXX: Note that we don't consider this an error, but instead
     *      silently ignore it. We may want to consider this behavior
     *      more carefully.
     */
    if (H5PL_allow_plugins_g)
        H5PL_plugin_control_mask_g = mask;

    FUNC_LEAVE_NOAPI(ret_value)

} /* end H5PL__set_plugin_control_mask() */

/*-------------------------------------------------------------------------
 * Function:    H5PL_init
 *
 * Purpose:     Initialize the interface from some other layer.
 *
 * Return:      Success:        non-negative
 *              Failure:        negative
 *-------------------------------------------------------------------------
 */
herr_t
H5PL_init(void)
{
    char  *env_var   = NULL;
    herr_t ret_value = SUCCEED;

    FUNC_ENTER_NOAPI(FAIL)

    /* Check the environment variable to determine if the user wants
     * to ignore plugins. The special symbol H5PL_NO_PLUGIN (defined in
     * H5PLpublic.h) means we don't want to load plugins.
     */
    if (NULL != (env_var = HDgetenv(HDF5_PLUGIN_PRELOAD)))
        if (!HDstrcmp(env_var, H5PL_NO_PLUGIN)) {
            H5PL_plugin_control_mask_g = 0;
            H5PL_allow_plugins_g       = FALSE;
        }

    /* Create the table of previously-loaded plugins */
    if (H5PL__create_plugin_cache() < 0)
        HGOTO_ERROR(H5E_PLUGIN, H5E_CANTINIT, FAIL, "can't create plugin cache");

    /* Create the table of search paths for dynamic libraries */
    if (H5PL__create_path_table() < 0)
        HGOTO_ERROR(H5E_PLUGIN, H5E_CANTINIT, FAIL, "can't create plugin search path table");

done:
    FUNC_LEAVE_NOAPI(ret_value)
}

/*-------------------------------------------------------------------------
 * Function:    H5PL_term_package
 *
 * Purpose:     Terminate the H5PL interface: release all memory, reset all
 *              global variables to initial values. This only happens if all
 *              types have been destroyed from other interfaces.
 *
 * Return:      Success:    Positive if any action was taken that might
 *                          affect some other interface; zero otherwise
 *              Failure:    Negative
 *
 *-------------------------------------------------------------------------
 */
int
H5PL_term_package(void)
{
    hbool_t already_closed = FALSE;
    int     ret_value      = 0;

    FUNC_ENTER_NOAPI_NOINIT

    /* Close the plugin cache.
     * We need to bump the return value if we did any real work here.
     */
    if (H5PL__close_plugin_cache(&already_closed) < 0)
        HGOTO_ERROR(H5E_PLUGIN, H5E_CANTFREE, (-1), "problem closing plugin cache");
    if (!already_closed)
        ret_value++;

    /* Close the search path table and free the paths */
    if (H5PL__close_path_table() < 0)
        HGOTO_ERROR(H5E_PLUGIN, H5E_CANTFREE, (-1), "problem closing search path table");

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5PL_term_package() */

/*-------------------------------------------------------------------------
 * Function:    H5PL_load
 *
 * Purpose:     Given the plugin type and identifier, this function searches
 *              for and, if found, loads a dynamic plugin library.
 *
 *              The function searches first in the cached plugins and then
 *              in the paths listed in the path table.
 *
 * Return:      Success:    A pointer to the plugin info
 *              Failure:    NULL
 *
 *-------------------------------------------------------------------------
 */
const void *
H5PL_load(H5PL_type_t type, const H5PL_key_t *key)
{
    H5PL_search_params_t search_params;       /* Plugin search parameters     */
    hbool_t              found       = FALSE; /* Whether the plugin was found */
    const void          *plugin_info = NULL;  /* Information from the plugin  */
    const void          *ret_value   = NULL;

    FUNC_ENTER_NOAPI(NULL)

    /* Check if plugins can be loaded for this plugin type */
    switch (type) {
        case H5PL_TYPE_FILTER:
            if ((H5PL_plugin_control_mask_g & H5PL_FILTER_PLUGIN) == 0)
                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTLOAD, NULL, "filter plugins disabled");
            break;

        case H5PL_TYPE_VOL:
            if ((H5PL_plugin_control_mask_g & H5PL_VOL_PLUGIN) == 0)
                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTLOAD, NULL,
                            "Virtual Object Layer (VOL) driver plugins disabled");
            break;

        case H5PL_TYPE_VFD:
            if ((H5PL_plugin_control_mask_g & H5PL_VFD_PLUGIN) == 0)
                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTLOAD, NULL, "Virtual File Driver (VFD) plugins disabled");
            break;

        case H5PL_TYPE_ERROR:
        case H5PL_TYPE_NONE:
        default:
            HGOTO_ERROR(H5E_PLUGIN, H5E_CANTLOAD, NULL, "Invalid plugin type specified");
    }

    /* Set up the search parameters */
    search_params.type = type;
    search_params.key  = key;

    /* Search in the table of already loaded plugin libraries */
    if (H5PL__find_plugin_in_cache(&search_params, &found, &plugin_info) < 0)
        HGOTO_ERROR(H5E_PLUGIN, H5E_CANTGET, NULL, "search in plugin cache failed");

    /* If not found, try iterating through the path table to find an appropriate plugin */
    if (!found)
        if (H5PL__find_plugin_in_path_table(&search_params, &found, &plugin_info) < 0)
            HGOTO_ERROR(H5E_PLUGIN, H5E_CANTGET, NULL,
                        "can't find plugin in the paths either set by HDF5_PLUGIN_PATH, or default location, "
                        "or set by H5PLxxx functions");

    /* Set the return value we found the plugin */
    if (found)
        ret_value = plugin_info;
    else
        HGOTO_ERROR(H5E_PLUGIN, H5E_NOTFOUND, NULL,
                    "can't find plugin. Check either HDF5_VOL_CONNECTOR, HDF5_PLUGIN_PATH, default location, "
                    "or path set by H5PLxxx functions");

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5PL_load() */

/*-------------------------------------------------------------------------
 * Function:    H5PL__open
 *
 * Purpose:     Opens a plugin.
 *
 *              `path` specifies the path to the plugin library file.
 *
 *              `type` specifies the type of plugin being searched for and
 *              will be used to verify that a loaded plugin matches the
 *              type requested. H5PL_TYPE_NONE may be passed, in which case
 *              no plugin type verification is performed. This is most
 *              useful when iterating over available plugins without regard
 *              to their types.
 *
 *              `key` specifies the information that will be used to find a
 *              specific plugin. For filter plugins, this is typically an
 *              integer identifier. For VOL connector and VFD plugins, this
 *              is typically either an integer identifier or a name string.
 *              After a plugin has been opened, this information will be
 *              compared against the relevant information provided by the
 *              plugin to ensure that the plugin is a match. If
 *              H5PL_TYPE_NONE is provided for `type`, then `key` should be
 *              NULL.
 *
 *              On successful open of a plugin, the `success` parameter
 *              will be set to TRUE and the `plugin_type` and `plugin_info`
 *              parameters will be filled appropriately. On failure, the
 *              `success` parameter will be set to FALSE, the `plugin_type`
 *              parameter will be set to H5PL_TYPE_ERROR and the
 *              `plugin_info` parameter will be set to NULL.
 *
 * Return:      SUCCEED/FAIL
 *
 *-------------------------------------------------------------------------
 */
/* NOTE: We turn off -Wpedantic in gcc to quiet a warning about converting
 *       object pointers to function pointers, which is undefined in ANSI C.
 *       This is basically unavoidable due to the nature of dlsym() and *is*
 *       defined in POSIX, so it's fine.
 *
 *       This pragma only needs to surround the assignment of the
 *       get_plugin_info function pointer, but early (4.4.7, at least) gcc
 *       only allows diagnostic pragmas to be toggled outside of functions.
 */
H5_GCC_CLANG_DIAG_OFF("pedantic")
herr_t
H5PL__open(const char *path, H5PL_type_t type, const H5PL_key_t *key, hbool_t *success,
           H5PL_type_t *plugin_type, const void **plugin_info)
{
    H5PL_HANDLE            handle          = NULL;
    H5PL_get_plugin_type_t get_plugin_type = NULL;
    H5PL_get_plugin_info_t get_plugin_info = NULL;
    H5PL_type_t            loaded_plugin_type;
    H5PL_key_t             tmp_key;
    herr_t                 ret_value = SUCCEED;

    FUNC_ENTER_PACKAGE

    /* Check args - Just assert on package functions */
    assert(path);
    if (type == H5PL_TYPE_NONE)
        assert(!key);
    assert(success);
    assert(plugin_info);

    /* Initialize out parameters */
    *success     = FALSE;
    *plugin_info = NULL;
    if (plugin_type)
        *plugin_type = H5PL_TYPE_ERROR;

    /* There are different reasons why a library can't be open, e.g. wrong architecture.
     * If we can't open the library, just return.
     */
    if (NULL == (handle = H5PL_OPEN_DLIB(path))) {
        H5PL_CLR_ERROR; /* clear error */
        HGOTO_DONE(SUCCEED);
    }

    /* Return a handle for the function H5PLget_plugin_type in the dynamic library.
     * The plugin library is supposed to define this function.
     */
    if (NULL == (get_plugin_type = (H5PL_get_plugin_type_t)H5PL_GET_LIB_FUNC(handle, "H5PLget_plugin_type")))
        HGOTO_DONE(SUCCEED);

    /* Return a handle for the function H5PLget_plugin_info in the dynamic library.
     * The plugin library is supposed to define this function.
     */
    if (NULL == (get_plugin_info = (H5PL_get_plugin_info_t)H5PL_GET_LIB_FUNC(handle, "H5PLget_plugin_info")))
        HGOTO_DONE(SUCCEED);

    /* Check the plugin type and return if it doesn't match the one passed in */
    loaded_plugin_type = (H5PL_type_t)(*get_plugin_type)();
    if ((type != H5PL_TYPE_NONE) && (type != loaded_plugin_type))
        HGOTO_DONE(SUCCEED);

    /* Get the plugin information */
    switch (loaded_plugin_type) {
        case H5PL_TYPE_FILTER: {
            const H5Z_class2_t *filter_info;

            /* Get the plugin info */
            if (NULL == (filter_info = (const H5Z_class2_t *)(*get_plugin_info)()))
                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTGET, FAIL, "can't get filter info from plugin");

            /* Setup temporary plugin key if one wasn't supplied */
            if (!key) {
                tmp_key.id = filter_info->id;
                key        = &tmp_key;
            }

            /* If the filter IDs match, we're done. Set the output parameters. */
            if (filter_info->id == key->id) {
                if (plugin_type)
                    *plugin_type = H5PL_TYPE_FILTER;
                *plugin_info = (const void *)filter_info;
                *success     = TRUE;
            }

            break;
        }

        case H5PL_TYPE_VOL: {
            const void *cls;

            /* Get the plugin info */
            if (NULL == (cls = (const void *)(*get_plugin_info)()))
                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTGET, FAIL, "can't get VOL connector info from plugin");

            /* Setup temporary plugin key if one wasn't supplied */
            if (!key) {
                tmp_key.vol.kind   = H5VL_GET_CONNECTOR_BY_NAME;
                tmp_key.vol.u.name = ((const H5VL_class_t *)cls)->name;
                key                = &tmp_key;
            }

            /* Ask VOL interface if this class is the one we are looking for and is compatible, etc */
            if (H5VL_check_plugin_load(cls, key, success) < 0)
                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTLOAD, FAIL, "VOL connector compatibility check failed");

            /* Check for finding the correct plugin */
            if (*success) {
                if (plugin_type)
                    *plugin_type = H5PL_TYPE_VOL;
                *plugin_info = cls;
            }

            break;
        }

        case H5PL_TYPE_VFD: {
            const void *cls;

            /* Get the plugin info */
            if (NULL == (cls = (const void *)(*get_plugin_info)()))
                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTGET, FAIL, "can't get VFD info from plugin");

            /* Setup temporary plugin key if one wasn't supplied */
            if (!key) {
                tmp_key.vfd.kind   = H5FD_GET_DRIVER_BY_NAME;
                tmp_key.vfd.u.name = ((const H5FD_class_t *)cls)->name;
                key                = &tmp_key;
            }

            /* Ask VFD interface if this class is the one we are looking for and is compatible, etc */
            if (H5FD_check_plugin_load(cls, key, success) < 0)
                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTLOAD, FAIL, "VFD compatibility check failed");

            /* Check for finding the correct plugin */
            if (*success) {
                if (plugin_type)
                    *plugin_type = H5PL_TYPE_VFD;
                *plugin_info = cls;
            }

            break;
        }

        case H5PL_TYPE_ERROR:
        case H5PL_TYPE_NONE:
        default:
            HGOTO_ERROR(H5E_PLUGIN, H5E_CANTGET, FAIL, "Invalid plugin type specified");
    } /* end switch */

    /* If we found the correct plugin, store it in the cache */
    if (*success)
        if (H5PL__add_plugin(loaded_plugin_type, key, handle))
            HGOTO_ERROR(H5E_PLUGIN, H5E_CANTINSERT, FAIL, "unable to add new plugin to plugin cache");

done:
    if (!(*success) && handle)
        if (H5PL__close(handle) < 0)
            HDONE_ERROR(H5E_PLUGIN, H5E_CLOSEERROR, FAIL, "can't close dynamic library");

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5PL__open() */
H5_GCC_CLANG_DIAG_ON("pedantic")

/*-------------------------------------------------------------------------
 * Function:    H5PL__close
 *
 * Purpose:     Closes the handle for dynamic library
 *
 * Return:      SUCCEED/FAIL
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5PL__close(H5PL_HANDLE handle)
{
    FUNC_ENTER_PACKAGE_NOERR

    H5PL_CLOSE_LIB(handle);

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5PL__close() */

/*-------------------------------------------------------------------------
 * Function:    H5PL_iterate
 *
 * Purpose:     Iterates over all the available plugins and calls the
 *              specified callback function on each plugin.
 *
 * Return:      H5_ITER_CONT if all plugins are processed successfully
 *              H5_ITER_STOP if short-circuit success occurs while
 *                  processing plugins
 *              H5_ITER_ERROR if an error occurs while processing plugins
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5PL_iterate(H5PL_iterate_type_t iter_type, H5PL_iterate_t iter_op, void *op_data)
{
    herr_t ret_value = H5_ITER_CONT;

    FUNC_ENTER_NOAPI_NOERR

    ret_value = H5PL__path_table_iterate(iter_type, iter_op, op_data);

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5PL_iterate() */