git.ozlabs.org Git - ccan/blob - ccan/ntdb/test/helprun-layout.c

   1 /* NTDB tools to create various canned database layouts. */
   2 #include "layout.h"
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include <assert.h>
   6 #include <ccan/err/err.h>
   7 #include "logging.h"
   8
   9 struct ntdb_layout *new_ntdb_layout(void)
  10 {
  11         struct ntdb_layout *layout = malloc(sizeof(*layout));
  12         layout->num_elems = 0;
  13         layout->elem = NULL;
  14         return layout;
  15 }
  16
  17 static void add(struct ntdb_layout *layout, union ntdb_layout_elem elem)
  18 {
  19         layout->elem = realloc(layout->elem,
  20                                sizeof(layout->elem[0])
  21                                * (layout->num_elems+1));
  22         layout->elem[layout->num_elems++] = elem;
  23 }
  24
  25 void ntdb_layout_add_freetable(struct ntdb_layout *layout)
  26 {
  27         union ntdb_layout_elem elem;
  28         elem.base.type = FREETABLE;
  29         add(layout, elem);
  30 }
  31
  32 void ntdb_layout_add_free(struct ntdb_layout *layout, ntdb_len_t len,
  33                          unsigned ftable)
  34 {
  35         union ntdb_layout_elem elem;
  36         elem.base.type = FREE;
  37         elem.free.len = len;
  38         elem.free.ftable_num = ftable;
  39         add(layout, elem);
  40 }
  41
  42 void ntdb_layout_add_capability(struct ntdb_layout *layout,
  43                                uint64_t type,
  44                                bool write_breaks,
  45                                bool check_breaks,
  46                                bool open_breaks,
  47                                ntdb_len_t extra)
  48 {
  49         union ntdb_layout_elem elem;
  50         elem.base.type = CAPABILITY;
  51         elem.capability.type = type;
  52         if (write_breaks)
  53                 elem.capability.type |= NTDB_CAP_NOWRITE;
  54         if (open_breaks)
  55                 elem.capability.type |= NTDB_CAP_NOOPEN;
  56         if (check_breaks)
  57                 elem.capability.type |= NTDB_CAP_NOCHECK;
  58         elem.capability.extra = extra;
  59         add(layout, elem);
  60 }
  61
  62 static NTDB_DATA dup_key(NTDB_DATA key)
  63 {
  64         NTDB_DATA ret;
  65         ret.dsize = key.dsize;
  66         ret.dptr = malloc(ret.dsize);
  67         memcpy(ret.dptr, key.dptr, ret.dsize);
  68         return ret;
  69 }
  70
  71 void ntdb_layout_add_used(struct ntdb_layout *layout,
  72                          NTDB_DATA key, NTDB_DATA data,
  73                          ntdb_len_t extra)
  74 {
  75         union ntdb_layout_elem elem;
  76         elem.base.type = DATA;
  77         elem.used.key = dup_key(key);
  78         elem.used.data = dup_key(data);
  79         elem.used.extra = extra;
  80         add(layout, elem);
  81 }
  82
  83 static ntdb_len_t free_record_len(ntdb_len_t len)
  84 {
  85         return sizeof(struct ntdb_used_record) + len;
  86 }
  87
  88 static ntdb_len_t data_record_len(struct tle_used *used)
  89 {
  90         ntdb_len_t len;
  91         len = sizeof(struct ntdb_used_record)
  92                 + used->key.dsize + used->data.dsize + used->extra;
  93         assert(len >= sizeof(struct ntdb_free_record));
  94         return len;
  95 }
  96
  97 static ntdb_len_t capability_len(struct tle_capability *cap)
  98 {
  99         return sizeof(struct ntdb_capability) + cap->extra;
 100 }
 101
 102 static ntdb_len_t freetable_len(struct tle_freetable *ftable)
 103 {
 104         return sizeof(struct ntdb_freetable);
 105 }
 106
 107 static void set_free_record(void *mem, ntdb_len_t len)
 108 {
 109         /* We do all the work in add_to_freetable */
 110 }
 111
 112 static void add_zero_pad(struct ntdb_used_record *u, size_t len, size_t extra)
 113 {
 114         if (extra)
 115                 ((char *)(u + 1))[len] = '\0';
 116 }
 117
 118 static void set_data_record(void *mem, struct ntdb_context *ntdb,
 119                             struct tle_used *used)
 120 {
 121         struct ntdb_used_record *u = mem;
 122
 123         set_header(ntdb, u, NTDB_USED_MAGIC, used->key.dsize, used->data.dsize,
 124                    used->key.dsize + used->data.dsize + used->extra);
 125         memcpy(u + 1, used->key.dptr, used->key.dsize);
 126         memcpy((char *)(u + 1) + used->key.dsize,
 127                used->data.dptr, used->data.dsize);
 128         add_zero_pad(u, used->key.dsize + used->data.dsize, used->extra);
 129 }
 130
 131 static void set_capability(void *mem, struct ntdb_context *ntdb,
 132                            struct tle_capability *cap, struct ntdb_header *hdr,
 133                            ntdb_off_t last_cap)
 134 {
 135         struct ntdb_capability *c = mem;
 136         ntdb_len_t len = sizeof(*c) - sizeof(struct ntdb_used_record) + cap->extra;
 137
 138         c->type = cap->type;
 139         c->next = 0;
 140         set_header(ntdb, &c->hdr, NTDB_CAP_MAGIC, 0, len, len);
 141
 142         /* Append to capability list. */
 143         if (!last_cap) {
 144                 hdr->capabilities = cap->base.off;
 145         } else {
 146                 c = (struct ntdb_capability *)((char *)hdr + last_cap);
 147                 c->next = cap->base.off;
 148         }
 149 }
 150
 151 static void set_freetable(void *mem, struct ntdb_context *ntdb,
 152                          struct tle_freetable *freetable, struct ntdb_header *hdr,
 153                          ntdb_off_t last_ftable)
 154 {
 155         struct ntdb_freetable *ftable = mem;
 156         memset(ftable, 0, sizeof(*ftable));
 157         set_header(ntdb, &ftable->hdr, NTDB_FTABLE_MAGIC, 0,
 158                         sizeof(*ftable) - sizeof(ftable->hdr),
 159                         sizeof(*ftable) - sizeof(ftable->hdr));
 160
 161         if (last_ftable) {
 162                 ftable = (struct ntdb_freetable *)((char *)hdr + last_ftable);
 163                 ftable->next = freetable->base.off;
 164         } else {
 165                 hdr->free_table = freetable->base.off;
 166         }
 167 }
 168
 169 static void add_to_freetable(struct ntdb_context *ntdb,
 170                              ntdb_off_t eoff,
 171                              ntdb_off_t elen,
 172                              unsigned ftable,
 173                              struct tle_freetable *freetable)
 174 {
 175         ntdb->ftable_off = freetable->base.off;
 176         ntdb->ftable = ftable;
 177         add_free_record(ntdb, eoff, sizeof(struct ntdb_used_record) + elen,
 178                         NTDB_LOCK_WAIT, false);
 179 }
 180
 181 /* Get bits from a value. */
 182 static uint32_t bits(uint64_t val, unsigned start, unsigned num)
 183 {
 184         assert(num <= 32);
 185         return (val >> start) & ((1U << num) - 1);
 186 }
 187
 188 static ntdb_off_t encode_offset(const struct ntdb_context *ntdb,
 189                                 ntdb_off_t new_off, uint32_t hash)
 190 {
 191         ntdb_off_t extra;
 192
 193         assert((new_off & (1ULL << NTDB_OFF_CHAIN_BIT)) == 0);
 194         assert((new_off >> (64 - NTDB_OFF_UPPER_STEAL)) == 0);
 195         /* We pack extra hash bits into the upper bits of the offset. */
 196         extra = bits(hash, ntdb->hash_bits, NTDB_OFF_UPPER_STEAL);
 197         extra <<= (64 - NTDB_OFF_UPPER_STEAL);
 198
 199         return new_off | extra;
 200 }
 201
 202 static ntdb_off_t hbucket_off(ntdb_len_t idx)
 203 {
 204         return sizeof(struct ntdb_header) + sizeof(struct ntdb_used_record)
 205                 + idx * sizeof(ntdb_off_t);
 206 }
 207
 208 /* FIXME: Our hash table handling here is primitive: we don't expand! */
 209 static void add_to_hashtable(struct ntdb_context *ntdb,
 210                              ntdb_off_t eoff,
 211                              NTDB_DATA key)
 212 {
 213         ntdb_off_t b_off;
 214         uint32_t h = ntdb_hash(ntdb, key.dptr, key.dsize);
 215
 216         b_off = hbucket_off(h & ((1 << ntdb->hash_bits)-1));
 217         if (ntdb_read_off(ntdb, b_off) != 0)
 218                 abort();
 219
 220         ntdb_write_off(ntdb, b_off, encode_offset(ntdb, eoff, h));
 221 }
 222
 223 static struct tle_freetable *find_ftable(struct ntdb_layout *layout, unsigned num)
 224 {
 225         unsigned i;
 226
 227         for (i = 0; i < layout->num_elems; i++) {
 228                 if (layout->elem[i].base.type != FREETABLE)
 229                         continue;
 230                 if (num == 0)
 231                         return &layout->elem[i].ftable;
 232                 num--;
 233         }
 234         abort();
 235 }
 236
 237 /* FIXME: Support NTDB_CONVERT */
 238 struct ntdb_context *ntdb_layout_get(struct ntdb_layout *layout,
 239                                    void (*freefn)(void *),
 240                                    union ntdb_attribute *attr)
 241 {
 242         unsigned int i;
 243         ntdb_off_t off, hdrlen, len, last_ftable, last_cap;
 244         char *mem;
 245         struct ntdb_context *ntdb;
 246
 247         /* Now populate our header, cribbing from a real NTDB header. */
 248         ntdb = ntdb_open("layout", NTDB_INTERNAL, O_RDWR, 0, attr);
 249
 250         off = sizeof(struct ntdb_header) + sizeof(struct ntdb_used_record)
 251                 + (sizeof(ntdb_off_t) << ntdb->hash_bits);
 252         hdrlen = off;
 253
 254         /* First pass of layout: calc lengths */
 255         for (i = 0; i < layout->num_elems; i++) {
 256                 union ntdb_layout_elem *e = &layout->elem[i];
 257                 e->base.off = off;
 258                 switch (e->base.type) {
 259                 case FREETABLE:
 260                         len = freetable_len(&e->ftable);
 261                         break;
 262                 case FREE:
 263                         len = free_record_len(e->free.len);
 264                         break;
 265                 case DATA:
 266                         len = data_record_len(&e->used);
 267                         break;
 268                 case CAPABILITY:
 269                         len = capability_len(&e->capability);
 270                         break;
 271                 default:
 272                         abort();
 273                 }
 274                 off += len;
 275         }
 276
 277         mem = malloc(off);
 278         /* Fill with some weird pattern. */
 279         memset(mem, 0x99, off);
 280         memcpy(mem, ntdb->file->map_ptr, hdrlen);
 281
 282         /* Mug the ntdb we have to make it use this. */
 283         freefn(ntdb->file->map_ptr);
 284         ntdb->file->map_ptr = mem;
 285         ntdb->file->map_size = off;
 286
 287         last_ftable = 0;
 288         last_cap = 0;
 289         for (i = 0; i < layout->num_elems; i++) {
 290                 union ntdb_layout_elem *e = &layout->elem[i];
 291                 switch (e->base.type) {
 292                 case FREETABLE:
 293                         set_freetable(mem + e->base.off, ntdb, &e->ftable,
 294                                      (struct ntdb_header *)mem, last_ftable);
 295                         last_ftable = e->base.off;
 296                         break;
 297                 case FREE:
 298                         set_free_record(mem + e->base.off, e->free.len);
 299                         break;
 300                 case DATA:
 301                         set_data_record(mem + e->base.off, ntdb, &e->used);
 302                         break;
 303                 case CAPABILITY:
 304                         set_capability(mem + e->base.off, ntdb, &e->capability,
 305                                        (struct ntdb_header *)mem, last_cap);
 306                         last_cap = e->base.off;
 307                         break;
 308                 }
 309         }
 310         /* Must have a free table! */
 311         assert(last_ftable);
 312
 313         /* Now fill the free and hash tables. */
 314         for (i = 0; i < layout->num_elems; i++) {
 315                 union ntdb_layout_elem *e = &layout->elem[i];
 316                 switch (e->base.type) {
 317                 case FREE:
 318                         add_to_freetable(ntdb, e->base.off, e->free.len,
 319                                          e->free.ftable_num,
 320                                          find_ftable(layout, e->free.ftable_num));
 321                         break;
 322                 case DATA:
 323                         add_to_hashtable(ntdb, e->base.off, e->used.key);
 324                         break;
 325                 default:
 326                         break;
 327                 }
 328         }
 329
 330         ntdb->ftable_off = find_ftable(layout, 0)->base.off;
 331         return ntdb;
 332 }
 333
 334 void ntdb_layout_write(struct ntdb_layout *layout, void (*freefn)(void *),
 335                        union ntdb_attribute *attr, const char *filename)
 336 {
 337         struct ntdb_context *ntdb = ntdb_layout_get(layout, freefn, attr);
 338         int fd;
 339
 340         fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT,  0600);
 341         if (fd < 0)
 342                 err(1, "opening %s for writing", filename);
 343         if (write(fd, ntdb->file->map_ptr, ntdb->file->map_size)
 344             != ntdb->file->map_size)
 345                 err(1, "writing %s", filename);
 346         close(fd);
 347         ntdb_close(ntdb);
 348 }
 349
 350 void ntdb_layout_free(struct ntdb_layout *layout)
 351 {
 352         unsigned int i;
 353
 354         for (i = 0; i < layout->num_elems; i++) {
 355                 if (layout->elem[i].base.type == DATA) {
 356                         free(layout->elem[i].used.key.dptr);
 357                         free(layout->elem[i].used.data.dptr);
 358                 }
 359         }
 360         free(layout->elem);
 361         free(layout);
 362 }