git.ozlabs.org Git - ccan/blob - ccan/tdb2/test/layout.c

   1 /* TDB 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 "logging.h"
   7
   8 struct tdb_layout *new_tdb_layout(void)
   9 {
  10         struct tdb_layout *layout = malloc(sizeof(*layout));
  11         layout->num_elems = 0;
  12         layout->elem = NULL;
  13         layout->ftable = layout->htable = -1;
  14         return layout;
  15 }
  16
  17 static void add(struct tdb_layout *layout, union tdb_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 tdb_layout_add_free(struct tdb_layout *layout, tdb_len_t len)
  26 {
  27         union tdb_layout_elem elem;
  28         elem.base.type = FREE;
  29         elem.free.len = len;
  30         add(layout, elem);
  31 }
  32
  33 static struct tdb_data dup_key(struct tdb_data key)
  34 {
  35         struct tdb_data ret;
  36         ret.dsize = key.dsize;
  37         ret.dptr = malloc(ret.dsize);
  38         memcpy(ret.dptr, key.dptr, ret.dsize);
  39         return ret;
  40 }
  41
  42 void tdb_layout_add_used(struct tdb_layout *layout,
  43                          TDB_DATA key, TDB_DATA data,
  44                          tdb_len_t extra)
  45 {
  46         union tdb_layout_elem elem;
  47         elem.base.type = DATA;
  48         elem.used.key = dup_key(key);
  49         elem.used.data = dup_key(data);
  50         elem.used.extra = extra;
  51         add(layout, elem);
  52 }
  53
  54 void tdb_layout_add_hashtable(struct tdb_layout *layout,
  55                               unsigned int hash_bits,
  56                               tdb_len_t extra)
  57 {
  58         union tdb_layout_elem elem;
  59         elem.base.type = HASHTABLE;
  60         elem.hashtable.hash_bits = hash_bits;
  61         elem.hashtable.extra = extra;
  62         assert(layout->htable == -1U);
  63         layout->htable = layout->num_elems;
  64         add(layout, elem);
  65 }
  66
  67 void tdb_layout_add_freetable(struct tdb_layout *layout,
  68                               unsigned int num_zones,
  69                               unsigned int zone_bits,
  70                               unsigned int num_buckets,
  71                               tdb_len_t extra)
  72 {
  73         union tdb_layout_elem elem;
  74         elem.base.type = FREETABLE;
  75         elem.freetable.num_zones = num_zones;
  76         elem.freetable.zone_bits = zone_bits;
  77         elem.freetable.num_buckets = num_buckets;
  78         elem.freetable.extra = extra;
  79         assert(layout->ftable == -1U);
  80         layout->ftable = layout->num_elems;
  81         add(layout, elem);
  82 }
  83
  84 static tdb_len_t free_record_len(tdb_len_t len)
  85 {
  86         return sizeof(struct tdb_used_record) + len;
  87 }
  88
  89 static tdb_len_t data_record_len(struct tle_used *used)
  90 {
  91         tdb_len_t len;
  92         len = sizeof(struct tdb_used_record)
  93                 + used->key.dsize + used->data.dsize + used->extra;
  94         assert(len >= sizeof(struct tdb_free_record));
  95         return len;
  96 }
  97
  98 static tdb_len_t hashtable_len(struct tle_hashtable *htable)
  99 {
 100         return sizeof(struct tdb_used_record)
 101                 + (sizeof(tdb_off_t) << htable->hash_bits);
 102 }
 103
 104 static tdb_len_t freetable_len(struct tle_freetable *ftable)
 105 {
 106         return sizeof(struct tdb_used_record)
 107                 + (sizeof(tdb_off_t) * ftable->num_zones
 108                    * (ftable->num_buckets + 1));
 109 }
 110
 111 static void set_free_record(void *mem, tdb_len_t len)
 112 {
 113         /* We do all the work in add_to_freetable */
 114 }
 115
 116 static void set_data_record(void *mem, struct tdb_context *tdb,
 117                             struct tle_used *used)
 118 {
 119         struct tdb_used_record *u = mem;
 120
 121         set_header(tdb, u, used->key.dsize, used->data.dsize,
 122                    used->key.dsize + used->data.dsize + used->extra,
 123                    tdb_hash(tdb, used->key.dptr, used->key.dsize));
 124         memcpy(u + 1, used->key.dptr, used->key.dsize);
 125         memcpy((char *)(u + 1) + used->key.dsize,
 126                used->data.dptr, used->data.dsize);
 127 }
 128
 129 static void set_hashtable(void *mem, struct tdb_context *tdb,
 130                           struct tle_hashtable *htable)
 131 {
 132         struct tdb_used_record *u = mem;
 133         tdb_len_t len = sizeof(tdb_off_t) << htable->hash_bits;
 134
 135         set_header(tdb, u, 0, len, len + htable->extra, 0);
 136         memset(u + 1, 0, len);
 137 }
 138
 139 static void set_freetable(void *mem, struct tdb_context *tdb,
 140                           struct tle_freetable *ftable)
 141 {
 142         struct tdb_used_record *u = mem;
 143         tdb_len_t len = sizeof(tdb_off_t) * ftable->num_zones
 144                 * (ftable->num_buckets + 1);
 145         set_header(tdb, u, 0, len, len + ftable->extra, 0);
 146         memset(u + 1, 0, len);
 147 }
 148
 149 static void add_to_freetable(struct tdb_context *tdb,
 150                              tdb_off_t eoff,
 151                              tdb_off_t elen)
 152 {
 153         add_free_record(tdb, eoff, sizeof(struct tdb_used_record) + elen);
 154 }
 155
 156 static void add_to_hashtable(struct tdb_context *tdb,
 157                              tdb_off_t eoff,
 158                              struct tdb_data key)
 159 {
 160         uint64_t hash = tdb_hash(tdb, key.dptr, key.dsize);
 161         tdb_off_t hoff;
 162
 163         while (tdb_read_off(tdb, hoff = hash_off(tdb, hash)) != 0)
 164                 hash++;
 165
 166         tdb_write_off(tdb, hoff, eoff);
 167 }
 168
 169 /* FIXME: Support TDB_CONVERT */
 170 struct tdb_context *tdb_layout_get(struct tdb_layout *layout)
 171 {
 172         unsigned int i;
 173         tdb_off_t len;
 174         struct tdb_header *hdr;
 175         char *mem;
 176         struct tdb_context *tdb;
 177
 178         assert(layout->ftable != -1U);
 179         assert(layout->htable != -1U);
 180
 181         len = sizeof(struct tdb_header);
 182
 183         /* First pass of layout: calc lengths */
 184         for (i = 0; i < layout->num_elems; i++) {
 185                 union tdb_layout_elem *e = &layout->elem[i];
 186                 e->base.off = len;
 187                 switch (e->base.type) {
 188                 case FREE:
 189                         len += free_record_len(e->free.len);
 190                         break;
 191                 case DATA:
 192                         len += data_record_len(&e->used);
 193                         break;
 194                 case HASHTABLE:
 195                         len += hashtable_len(&e->hashtable);
 196                         break;
 197                 case FREETABLE:
 198                         len += freetable_len(&e->freetable);
 199                         break;
 200                 }
 201         }
 202
 203         mem = malloc(len);
 204         /* Now populate our header, cribbing from a real TDB header. */
 205         tdb = tdb_open(NULL, TDB_INTERNAL, O_RDWR, 0, &tap_log_attr);
 206         hdr = (void *)mem;
 207         *hdr = tdb->header;
 208         hdr->v.generation++;
 209         hdr->v.num_zones = layout->elem[layout->ftable].freetable.num_zones;
 210         hdr->v.zone_bits = layout->elem[layout->ftable].freetable.zone_bits;
 211         hdr->v.free_buckets
 212                 = layout->elem[layout->ftable].freetable.num_buckets;
 213         hdr->v.free_off = layout->elem[layout->ftable].base.off
 214                 + sizeof(struct tdb_used_record);
 215         hdr->v.hash_bits = layout->elem[layout->htable].hashtable.hash_bits;
 216         hdr->v.hash_off = layout->elem[layout->htable].base.off
 217                 + sizeof(struct tdb_used_record);
 218
 219         /* Mug the tdb we have to make it use this. */
 220         free(tdb->map_ptr);
 221         tdb->map_ptr = mem;
 222         tdb->map_size = len;
 223         header_changed(tdb);
 224
 225         for (i = 0; i < layout->num_elems; i++) {
 226                 union tdb_layout_elem *e = &layout->elem[i];
 227                 switch (e->base.type) {
 228                 case FREE:
 229                         set_free_record(mem + e->base.off, e->free.len);
 230                         break;
 231                 case DATA:
 232                         set_data_record(mem + e->base.off, tdb, &e->used);
 233                         break;
 234                 case HASHTABLE:
 235                         set_hashtable(mem + e->base.off, tdb, &e->hashtable);
 236                         break;
 237                 case FREETABLE:
 238                         set_freetable(mem + e->base.off, tdb, &e->freetable);
 239                         break;
 240                 }
 241         }
 242
 243         /* Now fill the free and hash tables. */
 244         for (i = 0; i < layout->num_elems; i++) {
 245                 union tdb_layout_elem *e = &layout->elem[i];
 246                 switch (e->base.type) {
 247                 case FREE:
 248                         add_to_freetable(tdb, e->base.off, e->free.len);
 249                         break;
 250                 case DATA:
 251                         add_to_hashtable(tdb, e->base.off, e->used.key);
 252                         break;
 253                 default:
 254                         break;
 255                 }
 256         }
 257
 258         return tdb;
 259 }