lib/util/util_tdb.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    tdb utility functions
   5
   6    Copyright (C) Andrew Tridgell 1992-2006
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "../lib/tdb_compat/tdb_compat.h"
  24 #include "../lib/util/util_tdb.h"
  25
  26 /* these are little tdb utility functions that are meant to make
  27    dealing with a tdb database a little less cumbersome in Samba */
  28
  29 /***************************************************************
  30  Make a TDB_DATA and keep the const warning in one place
  31 ****************************************************************/
  32
  33 TDB_DATA make_tdb_data(const uint8_t *dptr, size_t dsize)
  34 {
  35         TDB_DATA ret;
  36         ret.dptr = discard_const_p(uint8_t, dptr);
  37         ret.dsize = dsize;
  38         return ret;
  39 }
  40
  41 bool tdb_data_equal(TDB_DATA t1, TDB_DATA t2)
  42 {
  43         if (t1.dsize != t2.dsize) {
  44                 return false;
  45         }
  46         return (memcmp(t1.dptr, t2.dptr, t1.dsize) == 0);
  47 }
  48
  49 TDB_DATA string_tdb_data(const char *string)
  50 {
  51         return make_tdb_data((const uint8_t *)string, string ? strlen(string) : 0 );
  52 }
  53
  54 TDB_DATA string_term_tdb_data(const char *string)
  55 {
  56         return make_tdb_data((const uint8_t *)string, string ? strlen(string) + 1 : 0);
  57 }
  58
  59 /****************************************************************************
  60  Lock a chain by string. Return non-zero if lock failed.
  61 ****************************************************************************/
  62
  63 int tdb_lock_bystring(struct tdb_context *tdb, const char *keyval)
  64 {
  65         TDB_DATA key = string_term_tdb_data(keyval);
  66
  67         return tdb_chainlock(tdb, key);
  68 }
  69
  70 /****************************************************************************
  71  Unlock a chain by string.
  72 ****************************************************************************/
  73
  74 void tdb_unlock_bystring(struct tdb_context *tdb, const char *keyval)
  75 {
  76         TDB_DATA key = string_term_tdb_data(keyval);
  77
  78         tdb_chainunlock(tdb, key);
  79 }
  80
  81 /****************************************************************************
  82  Read lock a chain by string. Return non-zero if lock failed.
  83 ****************************************************************************/
  84
  85 int tdb_read_lock_bystring(struct tdb_context *tdb, const char *keyval)
  86 {
  87         TDB_DATA key = string_term_tdb_data(keyval);
  88
  89         return tdb_chainlock_read(tdb, key);
  90 }
  91
  92 /****************************************************************************
  93  Read unlock a chain by string.
  94 ****************************************************************************/
  95
  96 void tdb_read_unlock_bystring(struct tdb_context *tdb, const char *keyval)
  97 {
  98         TDB_DATA key = string_term_tdb_data(keyval);
  99
 100         tdb_chainunlock_read(tdb, key);
 101 }
 102
 103
 104 /****************************************************************************
 105  Fetch a int32_t value by a arbitrary blob key, return -1 if not found.
 106  Output is int32_t in native byte order.
 107 ****************************************************************************/
 108
 109 int32_t tdb_fetch_int32_byblob(struct tdb_context *tdb, TDB_DATA key)
 110 {
 111         TDB_DATA data;
 112         int32_t ret;
 113
 114         data = tdb_fetch_compat(tdb, key);
 115         if (!data.dptr || data.dsize != sizeof(int32_t)) {
 116                 SAFE_FREE(data.dptr);
 117                 return -1;
 118         }
 119
 120         ret = IVAL(data.dptr,0);
 121         SAFE_FREE(data.dptr);
 122         return ret;
 123 }
 124
 125 /****************************************************************************
 126  Fetch a int32_t value by string key, return -1 if not found.
 127  Output is int32_t in native byte order.
 128 ****************************************************************************/
 129
 130 int32_t tdb_fetch_int32(struct tdb_context *tdb, const char *keystr)
 131 {
 132         return tdb_fetch_int32_byblob(tdb, string_term_tdb_data(keystr));
 133 }
 134
 135 /****************************************************************************
 136  Store a int32_t value by an arbitrary blob key, return 0 on success, -ve on failure.
 137  Input is int32_t in native byte order. Output in tdb is in little-endian.
 138 ****************************************************************************/
 139
 140 int tdb_store_int32_byblob(struct tdb_context *tdb, TDB_DATA key, int32_t v)
 141 {
 142         TDB_DATA data;
 143         int32_t v_store;
 144
 145         SIVAL(&v_store,0,v);
 146         data.dptr = (unsigned char *)&v_store;
 147         data.dsize = sizeof(int32_t);
 148
 149         return tdb_store(tdb, key, data, TDB_REPLACE);
 150 }
 151
 152 /****************************************************************************
 153  Store a int32_t value by string key, return 0 on success, -ve on failure.
 154  Input is int32_t in native byte order. Output in tdb is in little-endian.
 155 ****************************************************************************/
 156
 157 int tdb_store_int32(struct tdb_context *tdb, const char *keystr, int32_t v)
 158 {
 159         return tdb_store_int32_byblob(tdb, string_term_tdb_data(keystr), v);
 160 }
 161
 162 /****************************************************************************
 163  Fetch a uint32_t value by a arbitrary blob key, return false if not found.
 164  Output is uint32_t in native byte order.
 165 ****************************************************************************/
 166
 167 bool tdb_fetch_uint32_byblob(struct tdb_context *tdb, TDB_DATA key, uint32_t *value)
 168 {
 169         TDB_DATA data;
 170
 171         data = tdb_fetch_compat(tdb, key);
 172         if (!data.dptr || data.dsize != sizeof(uint32_t)) {
 173                 SAFE_FREE(data.dptr);
 174                 return false;
 175         }
 176
 177         *value = IVAL(data.dptr,0);
 178         SAFE_FREE(data.dptr);
 179         return true;
 180 }
 181
 182 /****************************************************************************
 183  Fetch a uint32_t value by string key, return false if not found.
 184  Output is uint32_t in native byte order.
 185 ****************************************************************************/
 186
 187 bool tdb_fetch_uint32(struct tdb_context *tdb, const char *keystr, uint32_t *value)
 188 {
 189         return tdb_fetch_uint32_byblob(tdb, string_term_tdb_data(keystr), value);
 190 }
 191
 192 /****************************************************************************
 193  Store a uint32_t value by an arbitrary blob key, return true on success, false on failure.
 194  Input is uint32_t in native byte order. Output in tdb is in little-endian.
 195 ****************************************************************************/
 196
 197 bool tdb_store_uint32_byblob(struct tdb_context *tdb, TDB_DATA key, uint32_t value)
 198 {
 199         TDB_DATA data;
 200         uint32_t v_store;
 201         bool ret = true;
 202
 203         SIVAL(&v_store, 0, value);
 204         data.dptr = (unsigned char *)&v_store;
 205         data.dsize = sizeof(uint32_t);
 206
 207         if (tdb_store(tdb, key, data, TDB_REPLACE) != 0)
 208                 ret = false;
 209
 210         return ret;
 211 }
 212
 213 /****************************************************************************
 214  Store a uint32_t value by string key, return true on success, false on failure.
 215  Input is uint32_t in native byte order. Output in tdb is in little-endian.
 216 ****************************************************************************/
 217
 218 bool tdb_store_uint32(struct tdb_context *tdb, const char *keystr, uint32_t value)
 219 {
 220         return tdb_store_uint32_byblob(tdb, string_term_tdb_data(keystr), value);
 221 }
 222 /****************************************************************************
 223  Store a buffer by a null terminated string key.  Return 0 on success, -ve
 224  on failure.
 225 ****************************************************************************/
 226
 227 int tdb_store_bystring(struct tdb_context *tdb, const char *keystr, TDB_DATA data, int flags)
 228 {
 229         TDB_DATA key = string_term_tdb_data(keystr);
 230
 231         return tdb_store(tdb, key, data, flags);
 232 }
 233
 234 /****************************************************************************
 235  Fetch a buffer using a null terminated string key.  Don't forget to call
 236  free() on the result dptr.
 237 ****************************************************************************/
 238
 239 TDB_DATA tdb_fetch_bystring(struct tdb_context *tdb, const char *keystr)
 240 {
 241         TDB_DATA key = string_term_tdb_data(keystr);
 242
 243         return tdb_fetch_compat(tdb, key);
 244 }
 245
 246 /****************************************************************************
 247  Delete an entry using a null terminated string key.
 248 ****************************************************************************/
 249
 250 int tdb_delete_bystring(struct tdb_context *tdb, const char *keystr)
 251 {
 252         TDB_DATA key = string_term_tdb_data(keystr);
 253
 254         return tdb_delete(tdb, key);
 255 }
 256
 257 /****************************************************************************
 258  Atomic integer change. Returns old value. To create, set initial value in *oldval.
 259 ****************************************************************************/
 260
 261 int32_t tdb_change_int32_atomic(struct tdb_context *tdb, const char *keystr, int32_t *oldval, int32_t change_val)
 262 {
 263         int32_t val;
 264         int32_t ret = -1;
 265
 266         if (tdb_lock_bystring(tdb, keystr) != 0)
 267                 return -1;
 268
 269         if ((val = tdb_fetch_int32(tdb, keystr)) == -1) {
 270                 /* The lookup failed */
 271                 if (tdb_error(tdb) != TDB_ERR_NOEXIST) {
 272                         /* but not because it didn't exist */
 273                         goto err_out;
 274                 }
 275
 276                 /* Start with 'old' value */
 277                 val = *oldval;
 278
 279         } else {
 280                 /* It worked, set return value (oldval) to tdb data */
 281                 *oldval = val;
 282         }
 283
 284         /* Increment value for storage and return next time */
 285         val += change_val;
 286
 287         if (tdb_store_int32(tdb, keystr, val) != 0)
 288                 goto err_out;
 289
 290         ret = 0;
 291
 292   err_out:
 293
 294         tdb_unlock_bystring(tdb, keystr);
 295         return ret;
 296 }
 297
 298 /****************************************************************************
 299  Atomic unsigned integer change. Returns old value. To create, set initial value in *oldval.
 300 ****************************************************************************/
 301
 302 bool tdb_change_uint32_atomic(struct tdb_context *tdb, const char *keystr, uint32_t *oldval, uint32_t change_val)
 303 {
 304         uint32_t val;
 305         bool ret = false;
 306
 307         if (tdb_lock_bystring(tdb, keystr) != 0)
 308                 return false;
 309
 310         if (!tdb_fetch_uint32(tdb, keystr, &val)) {
 311                 /* It failed */
 312                 if (tdb_error(tdb) != TDB_ERR_NOEXIST) {
 313                         /* and not because it didn't exist */
 314                         goto err_out;
 315                 }
 316
 317                 /* Start with 'old' value */
 318                 val = *oldval;
 319
 320         } else {
 321                 /* it worked, set return value (oldval) to tdb data */
 322                 *oldval = val;
 323
 324         }
 325
 326         /* get a new value to store */
 327         val += change_val;
 328
 329         if (!tdb_store_uint32(tdb, keystr, val))
 330                 goto err_out;
 331
 332         ret = true;
 333
 334   err_out:
 335
 336         tdb_unlock_bystring(tdb, keystr);
 337         return ret;
 338 }
 339
 340 /****************************************************************************
 341  Allow tdb_delete to be used as a tdb_traversal_fn.
 342 ****************************************************************************/
 343
 344 int tdb_traverse_delete_fn(struct tdb_context *the_tdb, TDB_DATA key, TDB_DATA dbuf,
 345                      void *state)
 346 {
 347     return tdb_delete(the_tdb, key);
 348 }