summaryrefslogtreecommitdiff
path: root/lib/tdb2/test/layout.c
blob: 0bce5dd89e5fbe4e4f13df0be99a9768bcb45840 (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
/* TDB tools to create various canned database layouts. */
#include "layout.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <err.h>
#include "logging.h"

struct tdb_layout *new_tdb_layout(void)
{
	struct tdb_layout *layout = malloc(sizeof(*layout));
	layout->num_elems = 0;
	layout->elem = NULL;
	return layout;
}

static void add(struct tdb_layout *layout, union tdb_layout_elem elem)
{
	layout->elem = realloc(layout->elem,
			       sizeof(layout->elem[0])
			       * (layout->num_elems+1));
	layout->elem[layout->num_elems++] = elem;
}

void tdb_layout_add_freetable(struct tdb_layout *layout)
{
	union tdb_layout_elem elem;
	elem.base.type = FREETABLE;
	add(layout, elem);
}

void tdb_layout_add_free(struct tdb_layout *layout, tdb_len_t len,
			 unsigned ftable)
{
	union tdb_layout_elem elem;
	elem.base.type = FREE;
	elem.free.len = len;
	elem.free.ftable_num = ftable;
	add(layout, elem);
}

void tdb_layout_add_capability(struct tdb_layout *layout,
			       uint64_t type,
			       bool write_breaks,
			       bool check_breaks,
			       bool open_breaks,
			       tdb_len_t extra)
{
	union tdb_layout_elem elem;
	elem.base.type = CAPABILITY;
	elem.capability.type = type;
	if (write_breaks)
		elem.capability.type |= TDB_CAP_NOWRITE;
	if (open_breaks)
		elem.capability.type |= TDB_CAP_NOOPEN;
	if (check_breaks)
		elem.capability.type |= TDB_CAP_NOCHECK;
	elem.capability.extra = extra;
	add(layout, elem);
}

static struct tdb_data dup_key(struct tdb_data key)
{
	struct tdb_data ret;
	ret.dsize = key.dsize;
	ret.dptr = malloc(ret.dsize);
	memcpy(ret.dptr, key.dptr, ret.dsize);
	return ret;
}

void tdb_layout_add_used(struct tdb_layout *layout,
			 TDB_DATA key, TDB_DATA data,
			 tdb_len_t extra)
{
	union tdb_layout_elem elem;
	elem.base.type = DATA;
	elem.used.key = dup_key(key);
	elem.used.data = dup_key(data);
	elem.used.extra = extra;
	add(layout, elem);
}

static tdb_len_t free_record_len(tdb_len_t len)
{
	return sizeof(struct tdb_used_record) + len;
}

static tdb_len_t data_record_len(struct tle_used *used)
{
	tdb_len_t len;
	len = sizeof(struct tdb_used_record)
		+ used->key.dsize + used->data.dsize + used->extra;
	assert(len >= sizeof(struct tdb_free_record));
	return len;
}

static tdb_len_t hashtable_len(struct tle_hashtable *htable)
{
	return sizeof(struct tdb_used_record)
		+ (sizeof(tdb_off_t) << TDB_SUBLEVEL_HASH_BITS)
		+ htable->extra;
}

static tdb_len_t capability_len(struct tle_capability *cap)
{
	return sizeof(struct tdb_capability) + cap->extra;
}

static tdb_len_t freetable_len(struct tle_freetable *ftable)
{
	return sizeof(struct tdb_freetable);
}

static void set_free_record(void *mem, tdb_len_t len)
{
	/* We do all the work in add_to_freetable */
}

static void add_zero_pad(struct tdb_used_record *u, size_t len, size_t extra)
{
	if (extra)
		((char *)(u + 1))[len] = '\0';
}

static void set_data_record(void *mem, struct tdb_context *tdb,
			    struct tle_used *used)
{
	struct tdb_used_record *u = mem;

	set_header(tdb, u, TDB_USED_MAGIC, used->key.dsize, used->data.dsize,
		   used->key.dsize + used->data.dsize + used->extra,
		   tdb_hash(tdb, used->key.dptr, used->key.dsize));
	memcpy(u + 1, used->key.dptr, used->key.dsize);
	memcpy((char *)(u + 1) + used->key.dsize,
	       used->data.dptr, used->data.dsize);
	add_zero_pad(u, used->key.dsize + used->data.dsize, used->extra);
}

static void set_hashtable(void *mem, struct tdb_context *tdb,
			  struct tle_hashtable *htable)
{
	struct tdb_used_record *u = mem;
	tdb_len_t len = sizeof(tdb_off_t) << TDB_SUBLEVEL_HASH_BITS;

	set_header(tdb, u, TDB_HTABLE_MAGIC, 0, len, len + htable->extra, 0);
	memset(u + 1, 0, len);
	add_zero_pad(u, len, htable->extra);
}

static void set_capability(void *mem, struct tdb_context *tdb,
			   struct tle_capability *cap, struct tdb_header *hdr,
			   tdb_off_t last_cap)
{
	struct tdb_capability *c = mem;
	tdb_len_t len = sizeof(*c) - sizeof(struct tdb_used_record) + cap->extra;

	c->type = cap->type;
	c->next = 0;
	set_header(tdb, &c->hdr, TDB_CAP_MAGIC, 0, len, len, 0);

	/* Append to capability list. */
	if (!last_cap) {
		hdr->capabilities = cap->base.off;
	} else {
		c = (struct tdb_capability *)((char *)hdr + last_cap);
		c->next = cap->base.off;
	}
}

static void set_freetable(void *mem, struct tdb_context *tdb,
			 struct tle_freetable *freetable, struct tdb_header *hdr,
			 tdb_off_t last_ftable)
{
	struct tdb_freetable *ftable = mem;
	memset(ftable, 0, sizeof(*ftable));
	set_header(tdb, &ftable->hdr, TDB_FTABLE_MAGIC, 0,
			sizeof(*ftable) - sizeof(ftable->hdr),
			sizeof(*ftable) - sizeof(ftable->hdr), 0);

	if (last_ftable) {
		ftable = (struct tdb_freetable *)((char *)hdr + last_ftable);
		ftable->next = freetable->base.off;
	} else {
		hdr->free_table = freetable->base.off;
	}
}

static void add_to_freetable(struct tdb_context *tdb,
			     tdb_off_t eoff,
			     tdb_off_t elen,
			     unsigned ftable,
			     struct tle_freetable *freetable)
{
	tdb->tdb2.ftable_off = freetable->base.off;
	tdb->tdb2.ftable = ftable;
	add_free_record(tdb, eoff, sizeof(struct tdb_used_record) + elen,
			TDB_LOCK_WAIT, false);
}

static tdb_off_t hbucket_off(tdb_off_t group_start, unsigned ingroup)
{
	return group_start
		+ (ingroup % (1 << TDB_HASH_GROUP_BITS)) * sizeof(tdb_off_t);
}

/* Get bits from a value. */
static uint32_t bits(uint64_t val, unsigned start, unsigned num)
{
	assert(num <= 32);
	return (val >> start) & ((1U << num) - 1);
}

/* We take bits from the top: that way we can lock whole sections of the hash
 * by using lock ranges. */
static uint32_t use_bits(uint64_t h, unsigned num, unsigned *used)
{
	*used += num;
	return bits(h, 64 - *used, num);
}

static tdb_off_t encode_offset(tdb_off_t new_off, unsigned bucket,
			       uint64_t h)
{
	return bucket
		| new_off
		| ((uint64_t)bits(h, 64 - TDB_OFF_UPPER_STEAL_EXTRA,
				  TDB_OFF_UPPER_STEAL_EXTRA)
		   << TDB_OFF_HASH_EXTRA_BIT);
}

/* FIXME: Our hash table handling here is primitive: we don't expand! */
static void add_to_hashtable(struct tdb_context *tdb,
			     tdb_off_t eoff,
			     struct tdb_data key)
{
	uint64_t h = tdb_hash(tdb, key.dptr, key.dsize);
	tdb_off_t b_off, group_start;
	unsigned i, group, in_group;
	unsigned used = 0;

	group = use_bits(h, TDB_TOPLEVEL_HASH_BITS-TDB_HASH_GROUP_BITS, &used);
	in_group = use_bits(h, TDB_HASH_GROUP_BITS, &used);

	group_start = offsetof(struct tdb_header, hashtable)
		+ group * (sizeof(tdb_off_t) << TDB_HASH_GROUP_BITS);

	for (i = 0; i < (1 << TDB_HASH_GROUP_BITS); i++) {
		unsigned bucket = (in_group + i) % (1 << TDB_HASH_GROUP_BITS);

		b_off = hbucket_off(group_start, bucket);
		if (tdb_read_off(tdb, b_off) == 0) {
			tdb_write_off(tdb, b_off,
				      encode_offset(eoff, in_group, h));
			return;
		}
	}
	abort();
}

static struct tle_freetable *find_ftable(struct tdb_layout *layout, unsigned num)
{
	unsigned i;

	for (i = 0; i < layout->num_elems; i++) {
		if (layout->elem[i].base.type != FREETABLE)
			continue;
		if (num == 0)
			return &layout->elem[i].ftable;
		num--;
	}
	abort();
}

/* FIXME: Support TDB_CONVERT */
struct tdb_context *tdb_layout_get(struct tdb_layout *layout,
				   void (*freefn)(void *),
				   union tdb_attribute *attr)
{
	unsigned int i;
	tdb_off_t off, len, last_ftable, last_cap;
	char *mem;
	struct tdb_context *tdb;

	off = sizeof(struct tdb_header);

	/* First pass of layout: calc lengths */
	for (i = 0; i < layout->num_elems; i++) {
		union tdb_layout_elem *e = &layout->elem[i];
		e->base.off = off;
		switch (e->base.type) {
		case FREETABLE:
			len = freetable_len(&e->ftable);
			break;
		case FREE:
			len = free_record_len(e->free.len);
			break;
		case DATA:
			len = data_record_len(&e->used);
			break;
		case HASHTABLE:
			len = hashtable_len(&e->hashtable);
			break;
		case CAPABILITY:
			len = capability_len(&e->capability);
			break;
		default:
			abort();
		}
		off += len;
	}

	mem = malloc(off);
	/* Fill with some weird pattern. */
	memset(mem, 0x99, off);
	/* Now populate our header, cribbing from a real TDB header. */
	tdb = tdb_open(NULL, TDB_INTERNAL, O_RDWR, 0, attr);
	memcpy(mem, tdb->file->map_ptr, sizeof(struct tdb_header));

	/* Mug the tdb we have to make it use this. */
	freefn(tdb->file->map_ptr);
	tdb->file->map_ptr = mem;
	tdb->file->map_size = off;

	last_ftable = 0;
	last_cap = 0;
	for (i = 0; i < layout->num_elems; i++) {
		union tdb_layout_elem *e = &layout->elem[i];
		switch (e->base.type) {
		case FREETABLE:
			set_freetable(mem + e->base.off, tdb, &e->ftable,
				     (struct tdb_header *)mem, last_ftable);
			last_ftable = e->base.off;
			break;
		case FREE:
			set_free_record(mem + e->base.off, e->free.len);
			break;
		case DATA:
			set_data_record(mem + e->base.off, tdb, &e->used);
			break;
		case HASHTABLE:
			set_hashtable(mem + e->base.off, tdb, &e->hashtable);
			break;
		case CAPABILITY:
			set_capability(mem + e->base.off, tdb, &e->capability,
				       (struct tdb_header *)mem, last_cap);
			last_cap = e->base.off;
			break;
		}
	}
	/* Must have a free table! */
	assert(last_ftable);

	/* Now fill the free and hash tables. */
	for (i = 0; i < layout->num_elems; i++) {
		union tdb_layout_elem *e = &layout->elem[i];
		switch (e->base.type) {
		case FREE:
			add_to_freetable(tdb, e->base.off, e->free.len,
					 e->free.ftable_num,
					 find_ftable(layout, e->free.ftable_num));
			break;
		case DATA:
			add_to_hashtable(tdb, e->base.off, e->used.key);
			break;
		default:
			break;
		}
	}

	tdb->tdb2.ftable_off = find_ftable(layout, 0)->base.off;
	return tdb;
}

void tdb_layout_write(struct tdb_layout *layout, void (*freefn)(void *),
		       union tdb_attribute *attr, const char *filename)
{
	struct tdb_context *tdb = tdb_layout_get(layout, freefn, attr);
	int fd;

	fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT,  0600);
	if (fd < 0)
		err(1, "opening %s for writing", filename);
	if (write(fd, tdb->file->map_ptr, tdb->file->map_size)
	    != tdb->file->map_size)
		err(1, "writing %s", filename);
	close(fd);
	tdb_close(tdb);
}

void tdb_layout_free(struct tdb_layout *layout)
{
	unsigned int i;

	for (i = 0; i < layout->num_elems; i++) {
		if (layout->elem[i].base.type == DATA) {
			free(layout->elem[i].used.key.dptr);
			free(layout->elem[i].used.data.dptr);
		}
	}
	free(layout->elem);
	free(layout);
}