aboutsummaryrefslogblamecommitdiff
path: root/lib/libmt/mtlib.c
blob: 0ada983823a105bf2f138aa0a70652bfcb0a9c9c (plain) (tree)
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
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570





































































                                                                             
                                                             


















































































































































































































































































































































































































































































































                                                                               








                                                                                                    












































                                                   







                                                                       










                                                         
                                                         

                                          
                                          
                                           
                                          




                                                       
                                                       


























































































































                                                                              
/*-
 * Copyright (c) 2013, 2014, 2015 Spectra Logic Corporation
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 *
 * Authors: Ken Merry           (Spectra Logic Corporation)
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/mtio.h>
#include <sys/queue.h>
#include <sys/sbuf.h>

#include <ctype.h>
#include <err.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdint.h>
#include <errno.h>
#include <bsdxml.h>
#include <mtlib.h>

/*
 * Called at the start of each XML element, and includes the list of
 * attributes for the element.
 */
void
mt_start_element(void *user_data, const char *name, const char **attr)
{
	int i;
	struct mt_status_data *mtinfo;
	struct mt_status_entry *entry;

	mtinfo = (struct mt_status_data *)user_data;

	if (mtinfo->error != 0)
		return;

	mtinfo->level++;
	if ((u_int)mtinfo->level >= (sizeof(mtinfo->cur_sb) /
            sizeof(mtinfo->cur_sb[0]))) {
		mtinfo->error = 1;
                snprintf(mtinfo->error_str, sizeof(mtinfo->error_str), 
		    "%s: too many nesting levels, %zd max", __func__,
		    sizeof(mtinfo->cur_sb) / sizeof(mtinfo->cur_sb[0]));
		return;
	}

        mtinfo->cur_sb[mtinfo->level] = sbuf_new_auto();
        if (mtinfo->cur_sb[mtinfo->level] == NULL) {
		mtinfo->error = 1;
                snprintf(mtinfo->error_str, sizeof(mtinfo->error_str),
		    "%s: Unable to allocate sbuf", __func__);
		return;
	}

	entry = malloc(sizeof(*entry));
	if (entry == NULL) {
		mtinfo->error = 1;
		snprintf(mtinfo->error_str, sizeof(mtinfo->error_str),
		    "%s: unable to allocate %zd bytes", __func__,
		    sizeof(*entry));
		return;
	}
	bzero(entry, sizeof(*entry)); 
	STAILQ_INIT(&entry->nv_list);
	STAILQ_INIT(&entry->child_entries);
	entry->entry_name = strdup(name);
	mtinfo->cur_entry[mtinfo->level] = entry;
	if (mtinfo->cur_entry[mtinfo->level - 1] == NULL) {
		STAILQ_INSERT_TAIL(&mtinfo->entries, entry, links);
	} else {
		STAILQ_INSERT_TAIL(
		    &mtinfo->cur_entry[mtinfo->level - 1]->child_entries,
		    entry, links);
		entry->parent = mtinfo->cur_entry[mtinfo->level - 1];
	}
	for (i = 0; attr[i] != NULL; i+=2) {
		struct mt_status_nv *nv;
		int need_nv;

		need_nv = 0;

		if (strcmp(attr[i], "size") == 0) {
			entry->size = strtoull(attr[i+1], NULL, 0);
		} else if (strcmp(attr[i], "type") == 0) {
			if (strcmp(attr[i+1], "int") == 0) {
				entry->var_type = MT_TYPE_INT;
			} else if (strcmp(attr[i+1], "uint") == 0) {
				entry->var_type = MT_TYPE_UINT;
			} else if (strcmp(attr[i+1], "str") == 0) {
				entry->var_type = MT_TYPE_STRING;
			} else if (strcmp(attr[i+1], "node") == 0) {
				entry->var_type = MT_TYPE_NODE;
			} else {
				need_nv = 1;
			}
		} else if (strcmp(attr[i], "fmt") == 0) {
			entry->fmt = strdup(attr[i+1]);
		} else if (strcmp(attr[i], "desc") == 0) {
			entry->desc = strdup(attr[i+1]);
		} else {
			need_nv = 1;
		}
		if (need_nv != 0) {
			nv = malloc(sizeof(*nv));
			if (nv == NULL) {
				mtinfo->error = 1;
				snprintf(mtinfo->error_str,
				    sizeof(mtinfo->error_str),
				    "%s: error allocating %zd bytes",
				    __func__, sizeof(*nv));
			}
			bzero(nv, sizeof(*nv));
			nv->name = strdup(attr[i]);
			nv->value = strdup(attr[i+1]);
			STAILQ_INSERT_TAIL(&entry->nv_list, nv, links);
		}
	}
}

/*
 * Called on XML element close.
 */
void
mt_end_element(void *user_data, const char *name)
{
	struct mt_status_data *mtinfo;
	char *str;

	mtinfo = (struct mt_status_data *)user_data;

	if (mtinfo->error != 0)
		return;

	if (mtinfo->cur_sb[mtinfo->level] == NULL) {
		mtinfo->error = 1;
		snprintf(mtinfo->error_str, sizeof(mtinfo->error_str),
		    "%s: no valid sbuf at level %d (name %s)", __func__,
		    mtinfo->level, name);
		return;
	}
	sbuf_finish(mtinfo->cur_sb[mtinfo->level]);
	str = strdup(sbuf_data(mtinfo->cur_sb[mtinfo->level]));
	if (str == NULL) {
		mtinfo->error = 1;
		snprintf(mtinfo->error_str, sizeof(mtinfo->error_str),
		    "%s can't allocate %zd bytes for string", __func__,
		    sbuf_len(mtinfo->cur_sb[mtinfo->level]));
		return;
	}

	if (strlen(str) == 0) {
		free(str);
		str = NULL;
	}
	if (str != NULL) {
		struct mt_status_entry *entry;

		entry = mtinfo->cur_entry[mtinfo->level];
		switch(entry->var_type) {
		case MT_TYPE_INT:
			entry->value_signed = strtoll(str, NULL, 0);
			break;
		case MT_TYPE_UINT:
			entry->value_unsigned = strtoull(str, NULL, 0);
			break;
		default:
			break;
		}
	}

	mtinfo->cur_entry[mtinfo->level]->value = str;

	sbuf_delete(mtinfo->cur_sb[mtinfo->level]);
	mtinfo->cur_sb[mtinfo->level] = NULL;
	mtinfo->cur_entry[mtinfo->level] = NULL;
	mtinfo->level--;
}

/*
 * Called to handle character strings in the current element.
 */
void
mt_char_handler(void *user_data, const XML_Char *str, int len)
{
	struct mt_status_data *mtinfo;

	mtinfo = (struct mt_status_data *)user_data;
	if (mtinfo->error != 0)
		return;

	sbuf_bcat(mtinfo->cur_sb[mtinfo->level], str, len);
}

void
mt_status_tree_sbuf(struct sbuf *sb, struct mt_status_entry *entry, int indent,
    void (*sbuf_func)(struct sbuf *sb, struct mt_status_entry *entry,
    void *arg), void *arg)
{
	struct mt_status_nv *nv;
	struct mt_status_entry *entry2;

	if (sbuf_func != NULL) {
		sbuf_func(sb, entry, arg);
	} else {
		sbuf_printf(sb, "%*sname: %s, value: %s, fmt: %s, size: %zd, "
		    "type: %d, desc: %s\n", indent, "", entry->entry_name,
		    entry->value, entry->fmt, entry->size, entry->var_type,
		    entry->desc);
		STAILQ_FOREACH(nv, &entry->nv_list, links) {
			sbuf_printf(sb, "%*snv: name: %s, value: %s\n",
			    indent + 1, "", nv->name, nv->value);
		}
	}

	STAILQ_FOREACH(entry2, &entry->child_entries, links)
		mt_status_tree_sbuf(sb, entry2, indent + 2, sbuf_func, arg);
}

void
mt_status_tree_print(struct mt_status_entry *entry, int indent,
    void (*print_func)(struct mt_status_entry *entry, void *arg), void *arg)
{

	if (print_func != NULL) {
		struct mt_status_entry *entry2;

		print_func(entry, arg);
		STAILQ_FOREACH(entry2, &entry->child_entries, links)
			mt_status_tree_print(entry2, indent + 2, print_func,
			    arg);
	} else {
		struct sbuf *sb;

		sb = sbuf_new_auto();
		if (sb == NULL)
			return;
		mt_status_tree_sbuf(sb, entry, indent, NULL, NULL);
		sbuf_finish(sb);

		printf("%s", sbuf_data(sb));
		sbuf_delete(sb);
	}
}

/*
 * Given a parameter name in the form "foo" or "foo.bar.baz", traverse the
 * tree looking for the parameter (the first case) or series of parameters
 * (second case).
 */
struct mt_status_entry *
mt_entry_find(struct mt_status_entry *entry, char *name)
{
	struct mt_status_entry *entry2;
	char *tmpname = NULL, *tmpname2 = NULL, *tmpstr = NULL;

	tmpname = strdup(name);
	if (tmpname == NULL)
		goto bailout;

	/* Save a pointer so we can free this later */
	tmpname2 = tmpname;

	tmpstr = strsep(&tmpname, ".");
	
	/*
	 * Is this the entry we're looking for?  Or do we have further
	 * child entries that we need to grab?
	 */
	if (strcmp(entry->entry_name, tmpstr) == 0) {
	 	if (tmpname == NULL) {
			/*
			 * There are no further child entries to find.  We
			 * have a complete match.
			 */
			free(tmpname2);
			return (entry);
		} else {
			/*
			 * There are more child entries that we need to find.
			 * Fall through to the recursive search off of this
			 * entry, below.  Use tmpname, which will contain
			 * everything after the first period.
			 */
			name = tmpname;
		}
	} 

	/*
	 * Recursively look for further entries.
	 */
	STAILQ_FOREACH(entry2, &entry->child_entries, links) {
		struct mt_status_entry *entry3;

		entry3 = mt_entry_find(entry2, name);
		if (entry3 != NULL) {
			free(tmpname2);
			return (entry3);
		}
	}

bailout:
	free(tmpname2);

	return (NULL);
}

struct mt_status_entry *
mt_status_entry_find(struct mt_status_data *status_data, char *name)
{
	struct mt_status_entry *entry, *entry2;

	STAILQ_FOREACH(entry, &status_data->entries, links) {
		entry2 = mt_entry_find(entry, name);
		if (entry2 != NULL)
			return (entry2);
	}

	return (NULL);
}

void
mt_status_entry_free(struct mt_status_entry *entry)
{
	struct mt_status_entry *entry2, *entry3;
	struct mt_status_nv *nv, *nv2;

	STAILQ_FOREACH_SAFE(entry2, &entry->child_entries, links, entry3) {
		STAILQ_REMOVE(&entry->child_entries, entry2, mt_status_entry,
		    links);
		mt_status_entry_free(entry2);
	}

	free(entry->entry_name);
	free(entry->value);
	free(entry->fmt);
	free(entry->desc);

	STAILQ_FOREACH_SAFE(nv, &entry->nv_list, links, nv2) {
		STAILQ_REMOVE(&entry->nv_list, nv, mt_status_nv, links);
		free(nv->name);
		free(nv->value);
		free(nv);
	}
	free(entry);
}

void
mt_status_free(struct mt_status_data *status_data)
{
	struct mt_status_entry *entry, *entry2;

	STAILQ_FOREACH_SAFE(entry, &status_data->entries, links, entry2) {
		STAILQ_REMOVE(&status_data->entries, entry, mt_status_entry,
		    links);
		mt_status_entry_free(entry);
	}
}

void
mt_entry_sbuf(struct sbuf *sb, struct mt_status_entry *entry, char *fmt)
{
	switch(entry->var_type) {
	case MT_TYPE_INT:
		if (fmt != NULL)
			sbuf_printf(sb, fmt, (intmax_t)entry->value_signed);
		else
			sbuf_printf(sb, "%jd",
				    (intmax_t)entry->value_signed);
		break;
	case MT_TYPE_UINT:
		if (fmt != NULL)
			sbuf_printf(sb, fmt, (uintmax_t)entry->value_unsigned);
		else
			sbuf_printf(sb, "%ju",
				    (uintmax_t)entry->value_unsigned);
		break;
	default:
		if (fmt != NULL)
			sbuf_printf(sb, fmt, entry->value);
		else
			sbuf_printf(sb, "%s", entry->value);
		break;
	}
}

void
mt_param_parent_print(struct mt_status_entry *entry,
    struct mt_print_params *print_params)
{
	if (entry->parent != NULL)
		mt_param_parent_print(entry->parent, print_params);

	if (((print_params->flags & MT_PF_INCLUDE_ROOT) == 0)
	 && (strcmp(entry->entry_name, print_params->root_name) == 0))
		return;

	printf("%s.", entry->entry_name);
}

void
mt_param_parent_sbuf(struct sbuf *sb, struct mt_status_entry *entry,
    struct mt_print_params *print_params)
{
	if (entry->parent != NULL)
		mt_param_parent_sbuf(sb, entry->parent, print_params);

	if (((print_params->flags & MT_PF_INCLUDE_ROOT) == 0)
	 && (strcmp(entry->entry_name, print_params->root_name) == 0))
		return;

	sbuf_printf(sb, "%s.", entry->entry_name);
}

void
mt_param_entry_sbuf(struct sbuf *sb, struct mt_status_entry *entry, void *arg)
{
	struct mt_print_params *print_params;

	print_params = (struct mt_print_params *)arg;

	/*
	 * We don't want to print nodes.
	 */
	if (entry->var_type == MT_TYPE_NODE)
		return;

	if ((print_params->flags & MT_PF_FULL_PATH)
	 && (entry->parent != NULL))
		mt_param_parent_sbuf(sb, entry->parent, print_params);

	sbuf_printf(sb, "%s: %s", entry->entry_name, entry->value);
	if ((print_params->flags & MT_PF_VERBOSE)
	 && (entry->desc != NULL)
	 && (strlen(entry->desc) > 0))
		sbuf_printf(sb, " (%s)", entry->desc);
	sbuf_printf(sb, "\n");

}

void
mt_param_entry_print(struct mt_status_entry *entry, void *arg)
{
	struct mt_print_params *print_params;

	print_params = (struct mt_print_params *)arg;

	/*
	 * We don't want to print nodes.
	 */
	if (entry->var_type == MT_TYPE_NODE)
		return;

	if ((print_params->flags & MT_PF_FULL_PATH)
	 && (entry->parent != NULL))
		mt_param_parent_print(entry->parent, print_params);

	printf("%s: %s", entry->entry_name, entry->value);
	if ((print_params->flags & MT_PF_VERBOSE)
	 && (entry->desc != NULL)
	 && (strlen(entry->desc) > 0))
		printf(" (%s)", entry->desc);
	printf("\n");
}

int
mt_protect_print(struct mt_status_data *status_data, int verbose)
{
	struct mt_status_entry *entry;
	const char *prot_name = MT_PROTECTION_NAME;
	struct mt_print_params print_params;

	snprintf(print_params.root_name, sizeof(print_params.root_name),
	    MT_PARAM_ROOT_NAME);
	print_params.flags = MT_PF_FULL_PATH;
	if (verbose != 0)
		print_params.flags |= MT_PF_VERBOSE;

	entry = mt_status_entry_find(status_data, __DECONST(char *,prot_name));
	if (entry == NULL)
		return (1);
	mt_status_tree_print(entry, 0, mt_param_entry_print, &print_params);

	return (0);
}

int
mt_param_list(struct mt_status_data *status_data, char *param_name, int quiet)
{
	struct mt_status_entry *entry;
	struct mt_print_params print_params;
	char root_name[20];

	snprintf(root_name, sizeof(root_name), "mtparamget");
	strlcpy(print_params.root_name, root_name,
	    sizeof(print_params.root_name));

	print_params.flags = MT_PF_FULL_PATH;
	if (quiet == 0)
		print_params.flags |= MT_PF_VERBOSE;

	if (param_name != NULL) {
		entry = mt_status_entry_find(status_data, param_name);
		if (entry == NULL)
			return (1);

		mt_param_entry_print(entry, &print_params);

		return (0);
	} else {
		entry = mt_status_entry_find(status_data, root_name);

		STAILQ_FOREACH(entry, &status_data->entries, links)
			mt_status_tree_print(entry, 0, mt_param_entry_print,
			    &print_params);
	}

	return (0);
}

static struct densities {
	int dens;
	int bpmm;
	int bpi;
	const char *name;
} dens[] = {
	/*
	 * Taken from T10 Project 997D 
	 * SCSI-3 Stream Device Commands (SSC)
	 * Revision 11, 4-Nov-97
	 *
	 * LTO 1-6 definitions obtained from the eighth edition of the
	 * IBM TotalStorage LTO Ultrium Tape Drive SCSI Reference
	 * (July 2007) and the second edition of the IBM System Storage LTO
	 * Tape Drive SCSI Reference (February 13, 2013).
	 *
	 * IBM 3592 definitions obtained from second edition of the IBM
	 * System Storage Tape Drive 3592 SCSI Reference (May 25, 2012).
	 *
	 * DAT-72 and DAT-160 bpi values taken from "HP StorageWorks DAT160
	 * tape drive white paper", dated June 2007.
	 *
	 * DAT-160 / SDLT220 density code (0x48) conflict information
	 * found here:
	 *
	 * http://h20564.www2.hp.com/hpsc/doc/public/display?docId=emr_na-c01065117&sp4ts.oid=429311
 	 * (Document ID c01065117)
	 */
	/*Num.  bpmm    bpi     Reference     */
	{ 0x1,	32,	800,	"X3.22-1983" },
	{ 0x2,	63,	1600,	"X3.39-1986" },
	{ 0x3,	246,	6250,	"X3.54-1986" },
	{ 0x5,	315,	8000,	"X3.136-1986" },
	{ 0x6,	126,	3200,	"X3.157-1987" },
	{ 0x7,	252,	6400,	"X3.116-1986" },
	{ 0x8,	315,	8000,	"X3.158-1987" },
	{ 0x9,	491,	37871,	"X3.180" },
	{ 0xA,	262,	6667,	"X3B5/86-199" },
	{ 0xB,	63,	1600,	"X3.56-1986" },
	{ 0xC,	500,	12690,	"HI-TC1" },
	{ 0xD,	999,	25380,	"HI-TC2" },
	{ 0xF,	394,	10000,	"QIC-120" },
	{ 0x10,	394,	10000,	"QIC-150" },
	{ 0x11,	630,	16000,	"QIC-320" },
	{ 0x12,	2034,	51667,	"QIC-1350" },
	{ 0x13,	2400,	61000,	"X3B5/88-185A" },
	{ 0x14,	1703,	43245,	"X3.202-1991" },
	{ 0x15,	1789,	45434,	"ECMA TC17" },
	{ 0x16,	394,	10000,	"X3.193-1990" },
	{ 0x17,	1673,	42500,	"X3B5/91-174" },
	{ 0x18,	1673,	42500,	"X3B5/92-50" },
	{ 0x19, 2460,   62500,  "DLTapeIII" },
	{ 0x1A, 3214,   81633,  "DLTapeIV(20GB)" },
	{ 0x1B, 3383,   85937,  "DLTapeIV(35GB)" },
	{ 0x1C, 1654,	42000,	"QIC-385M" },
	{ 0x1D,	1512,	38400,	"QIC-410M" },
	{ 0x1E, 1385,	36000,	"QIC-1000C" },
	{ 0x1F,	2666,	67733,	"QIC-2100C" },
	{ 0x20, 2666,	67733,	"QIC-6GB(M)" },
	{ 0x21,	2666,	67733,	"QIC-20GB(C)" },
	{ 0x22,	1600,	40640,	"QIC-2GB(C)" },
	{ 0x23, 2666,	67733,	"QIC-875M" },
	{ 0x24,	2400,	61000,	"DDS-2" },
	{ 0x25,	3816,	97000,	"DDS-3" },
	{ 0x26,	3816,	97000,	"DDS-4" },
	{ 0x27,	3056,	77611,	"Mammoth" },
	{ 0x28,	1491,	37871,	"X3.224" },
	{ 0x40, 4880,   123952, "LTO-1" },
	{ 0x41, 3868,   98250,  "DLTapeIV(40GB)" },
	{ 0x42, 7398,   187909, "LTO-2" },
	{ 0x44, 9638,   244805, "LTO-3" }, 
	{ 0x46, 12725,  323215, "LTO-4" }, 
	{ 0x47, 6417,   163000, "DAT-72" },
	/*
	 * XXX KDM note that 0x48 is also the density code for DAT-160.
	 * For some reason they used overlapping density codes.
	 */
#if 0
	{ 0x48, 6870,   174500, "DAT-160" },
#endif
	{ 0x48, 5236,   133000, "SDLTapeI(110)" },
	{ 0x49, 7598,   193000, "SDLTapeI(160)" },
	{ 0x4a,     0,       0, "T10000A" },
	{ 0x4b,     0,       0, "T10000B" },
	{ 0x4c,     0,       0, "T10000C" },
	{ 0x4d,     0,       0, "T10000D" },
	{ 0x51, 11800,  299720, "3592A1 (unencrypted)" },
	{ 0x52, 11800,  299720, "3592A2 (unencrypted)" },
	{ 0x53, 13452,  341681, "3592A3 (unencrypted)" },
	{ 0x54, 19686,  500024, "3592A4 (unencrypted)" },
	{ 0x55, 20670,  525018, "3592A5 (unencrypted)" },
	{ 0x56, 20670,  525018, "3592B5 (unencrypted)" },
	{ 0x58, 15142,  384607, "LTO-5" },
	{ 0x5A, 15142,  384607, "LTO-6" },
	{ 0x5C, 19107,  485318, "LTO-7" },
	{ 0x5D, 19107,  485318, "LTO-M8" },
	{ 0x5E, 20669,  524993, "LTO-8" },
	{ 0x71, 11800,  299720, "3592A1 (encrypted)" },
	{ 0x72, 11800,  299720, "3592A2 (encrypted)" },
	{ 0x73, 13452,  341681, "3592A3 (encrypted)" },
	{ 0x74, 19686,  500024, "3592A4 (encrypted)" },
	{ 0x75, 20670,  525018, "3592A5 (encrypted)" },
	{ 0x76, 20670,  525018, "3592B5 (encrypted)" },
	{ 0x8c,  1789,   45434, "EXB-8500c" },
	{ 0x90,  1703,   43245, "EXB-8200c" },
	{ 0, 0, 0, NULL }
};

const char *
mt_density_name(int density_num)
{
	struct densities *sd;

	/* densities 0 and 0x7f are handled as special cases */
	if (density_num == 0)
		return ("default");
	if (density_num == 0x7f)
		return ("same");

	for (sd = dens; sd->dens != 0; sd++)
		if (sd->dens == density_num)
			break;
	if (sd->dens == 0)
		return ("UNKNOWN");
	return (sd->name);
}

/*
 * Given a specific density number, return either the bits per inch or bits
 * per millimeter for the given density.
 */
int
mt_density_bp(int density_num, int bpi)
{
	struct densities *sd;

	for (sd = dens; sd->dens; sd++)
		if (sd->dens == density_num)
			break;
	if (sd->dens == 0)
		return (0);
	if (bpi)
		return (sd->bpi);
	else
		return (sd->bpmm);
}

int
mt_density_num(const char *density_name)
{
	struct densities *sd;
	size_t l = strlen(density_name);

	for (sd = dens; sd->dens; sd++)
		if (strncasecmp(sd->name, density_name, l) == 0)
			break;
	return (sd->dens);
}

/*
 * Get the current status XML string.
 * Returns 0 on success, -1 on failure (with errno set, and *xml_str == NULL).
 */
int
mt_get_xml_str(int mtfd, unsigned long cmd, char **xml_str)
{
	size_t alloc_len = 32768;
	struct mtextget extget;
	int error;

	*xml_str = NULL;

	for (;;) {
		bzero(&extget, sizeof(extget));
		*xml_str = malloc(alloc_len);
		if (*xml_str == NULL)
			return (-1);
		extget.status_xml = *xml_str;
		extget.alloc_len = alloc_len;

		error = ioctl(mtfd, cmd, (caddr_t)&extget);
		if (error == 0 && extget.status == MT_EXT_GET_OK)
			break;

		free(*xml_str);
		*xml_str = NULL;

		if (error != 0 || extget.status != MT_EXT_GET_NEED_MORE_SPACE)
			return (-1);

		/* The driver needs more space, so double and try again. */
		alloc_len *= 2;
	}
	return (0);
}

/*
 * Populate a struct mt_status_data from the XML string via mt_get_xml_str().
 *
 * Returns XML_STATUS_OK on success.
 * If XML_STATUS_ERROR is returned, errno may be set to indicate the reason.
 * The caller must check status_data->error.
 */
int
mt_get_status(char *xml_str, struct mt_status_data *status_data)
{
	XML_Parser parser;
	int retval;

	bzero(status_data, sizeof(*status_data));
	STAILQ_INIT(&status_data->entries);

	parser = XML_ParserCreate(NULL);
	if (parser == NULL) {
		errno = ENOMEM;
		return (XML_STATUS_ERROR);
	}

	XML_SetUserData(parser, status_data);
	XML_SetElementHandler(parser, mt_start_element, mt_end_element);
	XML_SetCharacterDataHandler(parser, mt_char_handler);

	retval = XML_Parse(parser, xml_str, strlen(xml_str), 1);
	XML_ParserFree(parser);
	return (retval);
}