source3/printing/printer_list.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Share Database of available printers.
   4    Copyright (C) Simo Sorce 2010
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "dbwrap.h"
  22 #include "printer_list.h"
  23
  24 #define PL_DB_NAME() lock_path("printer_list.tdb")
  25 #define PL_KEY_PREFIX "PRINTERLIST/PRN/"
  26 #define PL_KEY_FORMAT PL_KEY_PREFIX"%s"
  27 #define PL_TIMESTAMP_KEY "PRINTERLIST/GLOBAL/LAST_REFRESH"
  28 #define PL_DATA_FORMAT "ddPP"
  29 #define PL_TSTAMP_FORMAT "dd"
  30
  31 static struct db_context *get_printer_list_db(void)
  32 {
  33         static struct db_context *db;
  34
  35         if (db != NULL) {
  36                 return db;
  37         }
  38         db = db_open(NULL, PL_DB_NAME(), 0,
  39                      TDB_DEFAULT|TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH,
  40                      O_RDWR|O_CREAT, 0644);
  41         return db;
  42 }
  43
  44 bool printer_list_parent_init(void)
  45 {
  46         struct db_context *db;
  47
  48         /*
  49          * Open the tdb in the parent process (smbd) so that our
  50          * CLEAR_IF_FIRST optimization in tdb_reopen_all can properly
  51          * work.
  52          */
  53
  54         db = get_printer_list_db();
  55         if (db == NULL) {
  56                 DEBUG(1, ("could not open Printer List Database: %s\n",
  57                           strerror(errno)));
  58                 return false;
  59         }
  60         return true;
  61 }
  62
  63 NTSTATUS printer_list_get_printer(TALLOC_CTX *mem_ctx,
  64                                   const char *name,
  65                                   const char **comment,
  66                                   time_t *last_refresh)
  67 {
  68         struct db_context *db;
  69         char *key;
  70         TDB_DATA data;
  71         uint32_t time_h, time_l;
  72         char *nstr = NULL;
  73         char *cstr = NULL;
  74         NTSTATUS status;
  75         int ret;
  76
  77         db = get_printer_list_db();
  78         if (db == NULL) {
  79                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
  80         }
  81
  82         key = talloc_asprintf(mem_ctx, PL_KEY_FORMAT, name);
  83         if (!key) {
  84                 DEBUG(0, ("Failed to allocate key name!\n"));
  85                 return NT_STATUS_NO_MEMORY;
  86         }
  87
  88         data = dbwrap_fetch_bystring_upper(db, key, key);
  89         if (data.dptr == NULL) {
  90                 DEBUG(1, ("Failed to fetch record!\n"));
  91                 status = NT_STATUS_NOT_FOUND;
  92                 goto done;
  93         }
  94
  95         ret = tdb_unpack(data.dptr, data.dsize,
  96                          PL_DATA_FORMAT,
  97                          &time_h, &time_l, &nstr, &cstr);
  98         if (ret == -1) {
  99                 DEBUG(1, ("Failed to un pack printer data"));
 100                 status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 101                 goto done;
 102         }
 103
 104         if (last_refresh) {
 105                 *last_refresh = (time_t)(((uint64_t)time_h << 32) + time_l);
 106         }
 107
 108         if (comment) {
 109                 *comment = talloc_strdup(mem_ctx, cstr);
 110                 if (!*comment) {
 111                         DEBUG(1, ("Failed to strdup comment!\n"));
 112                         status = NT_STATUS_NO_MEMORY;
 113                         goto done;
 114                 }
 115         }
 116
 117         status = NT_STATUS_OK;
 118
 119 done:
 120         SAFE_FREE(nstr);
 121         SAFE_FREE(cstr);
 122         TALLOC_FREE(key);
 123         return status;
 124 }
 125
 126 NTSTATUS printer_list_set_printer(TALLOC_CTX *mem_ctx,
 127                                   const char *name,
 128                                   const char *comment,
 129                                   time_t last_refresh)
 130 {
 131         struct db_context *db;
 132         char *key;
 133         TDB_DATA data;
 134         uint64_t time_64;
 135         uint32_t time_h, time_l;
 136         const char *str = NULL;
 137         NTSTATUS status;
 138         int len;
 139
 140         db = get_printer_list_db();
 141         if (db == NULL) {
 142                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 143         }
 144
 145         key = talloc_asprintf(mem_ctx, PL_KEY_FORMAT, name);
 146         if (!key) {
 147                 DEBUG(0, ("Failed to allocate key name!\n"));
 148                 return NT_STATUS_NO_MEMORY;
 149         }
 150
 151         if (comment) {
 152                 str = comment;
 153         } else {
 154                 str = "";
 155         }
 156
 157         time_64 = last_refresh;
 158         time_l = time_64 & 0xFFFFFFFFL;
 159         time_h = time_64 >> 32;
 160
 161         len = tdb_pack(NULL, 0, PL_DATA_FORMAT, time_h, time_l, name, str);
 162
 163         data.dptr = talloc_array(key, uint8_t, len);
 164         if (!data.dptr) {
 165                 DEBUG(0, ("Failed to allocate tdb data buffer!\n"));
 166                 status = NT_STATUS_NO_MEMORY;
 167                 goto done;
 168         }
 169         data.dsize = len;
 170
 171         len = tdb_pack(data.dptr, data.dsize,
 172                        PL_DATA_FORMAT, time_h, time_l, name, str);
 173
 174         status = dbwrap_store_bystring_upper(db, key, data, TDB_REPLACE);
 175
 176 done:
 177         TALLOC_FREE(key);
 178         return status;
 179 }
 180
 181 NTSTATUS printer_list_get_last_refresh(time_t *last_refresh)
 182 {
 183         struct db_context *db;
 184         TDB_DATA data;
 185         uint32_t time_h, time_l;
 186         NTSTATUS status;
 187         int ret;
 188
 189         db = get_printer_list_db();
 190         if (db == NULL) {
 191                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 192         }
 193
 194         ZERO_STRUCT(data);
 195
 196         data = dbwrap_fetch_bystring(db, talloc_tos(), PL_TIMESTAMP_KEY);
 197         if (data.dptr == NULL) {
 198                 DEBUG(1, ("Failed to fetch record!\n"));
 199                 status = NT_STATUS_NOT_FOUND;
 200                 goto done;
 201         }
 202
 203         ret = tdb_unpack(data.dptr, data.dsize,
 204                          PL_TSTAMP_FORMAT, &time_h, &time_l);
 205         if (ret == -1) {
 206                 DEBUG(1, ("Failed to un pack printer data"));
 207                 status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 208                 goto done;
 209         }
 210
 211         *last_refresh = (time_t)(((uint64_t)time_h << 32) + time_l);
 212         status = NT_STATUS_OK;
 213
 214 done:
 215         return status;
 216 }
 217
 218 bool printer_list_need_refresh(void)
 219 {
 220         NTSTATUS status;
 221         time_t last_refresh;
 222         int timediff;
 223
 224         status = printer_list_get_last_refresh(&last_refresh);
 225         if (!NT_STATUS_IS_OK(status)) {
 226                 return true;
 227         }
 228         timediff = time_mono(NULL) - last_refresh;
 229
 230         if (timediff > 1 ) {
 231                 /* if refresh occurred more than 1s (TODO:use lp_printcap_cache_time) ago,
 232                  * then we need to refresh */
 233                 return true;
 234         } else if (timediff < 0) {
 235                 /* last_refresh newer than now. Seems we have no monotonic
 236                  * clock and the clock was adjusted backwards.
 237                  * we need to refresh which also resets last_refresh */
 238                 return true;
 239         }
 240
 241         return false;
 242 }
 243
 244 NTSTATUS printer_list_mark_reload(void)
 245 {
 246         struct db_context *db;
 247         TDB_DATA data;
 248         uint32_t time_h, time_l;
 249         time_t now = time_mono(NULL);
 250         NTSTATUS status;
 251         int len;
 252
 253         db = get_printer_list_db();
 254         if (db == NULL) {
 255                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 256         }
 257
 258         time_l = ((uint64_t)now) & 0xFFFFFFFFL;
 259         time_h = ((uint64_t)now) >> 32;
 260
 261         len = tdb_pack(NULL, 0, PL_TSTAMP_FORMAT, time_h, time_l);
 262
 263         data.dptr = talloc_array(talloc_tos(), uint8_t, len);
 264         if (!data.dptr) {
 265                 DEBUG(0, ("Failed to allocate tdb data buffer!\n"));
 266                 status = NT_STATUS_NO_MEMORY;
 267                 goto done;
 268         }
 269         data.dsize = len;
 270
 271         len = tdb_pack(data.dptr, data.dsize,
 272                        PL_TSTAMP_FORMAT, time_h, time_l);
 273
 274         status = dbwrap_store_bystring(db, PL_TIMESTAMP_KEY,
 275                                                 data, TDB_REPLACE);
 276
 277 done:
 278         TALLOC_FREE(data.dptr);
 279         return status;
 280 }
 281
 282 typedef int (printer_list_trv_fn_t)(struct db_record *, void *);
 283
 284 static NTSTATUS printer_list_traverse(printer_list_trv_fn_t *fn,
 285                                                 void *private_data)
 286 {
 287         struct db_context *db;
 288         int ret;
 289
 290         db = get_printer_list_db();
 291         if (db == NULL) {
 292                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 293         }
 294
 295         ret = db->traverse(db, fn, private_data);
 296         if (ret != 0) {
 297                 return NT_STATUS_UNSUCCESSFUL;
 298         }
 299
 300         return NT_STATUS_OK;
 301 }
 302
 303 struct printer_list_clean_state {
 304         time_t last_refresh;
 305         NTSTATUS status;
 306 };
 307
 308 static int printer_list_clean_fn(struct db_record *rec, void *private_data)
 309 {
 310         struct printer_list_clean_state *state =
 311                         (struct printer_list_clean_state *)private_data;
 312         uint32_t time_h, time_l;
 313         time_t refresh;
 314         char *name;
 315         char *comment;
 316         int ret;
 317
 318         /* skip anything that does not contain PL_DATA_FORMAT data */
 319         if (strncmp((char *)rec->key.dptr,
 320                     PL_KEY_PREFIX, sizeof(PL_KEY_PREFIX)-1)) {
 321                 return 0;
 322         }
 323
 324         ret = tdb_unpack(rec->value.dptr, rec->value.dsize,
 325                          PL_DATA_FORMAT, &time_h, &time_l, &name, &comment);
 326         if (ret == -1) {
 327                 DEBUG(1, ("Failed to un pack printer data"));
 328                 state->status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 329                 return -1;
 330         }
 331
 332         SAFE_FREE(name);
 333         SAFE_FREE(comment);
 334
 335         refresh = (time_t)(((uint64_t)time_h << 32) + time_l);
 336
 337         if (refresh < state->last_refresh) {
 338                 state->status = rec->delete_rec(rec);
 339                 if (!NT_STATUS_IS_OK(state->status)) {
 340                         return -1;
 341                 }
 342         }
 343
 344         return 0;
 345 }
 346
 347 NTSTATUS printer_list_clean_old(void)
 348 {
 349         struct printer_list_clean_state state;
 350         NTSTATUS status;
 351
 352         status = printer_list_get_last_refresh(&state.last_refresh);
 353         if (!NT_STATUS_IS_OK(status)) {
 354                 return status;
 355         }
 356
 357         state.status = NT_STATUS_OK;
 358
 359         status = printer_list_traverse(printer_list_clean_fn, &state);
 360         if (NT_STATUS_EQUAL(status, NT_STATUS_UNSUCCESSFUL) &&
 361             !NT_STATUS_IS_OK(state.status)) {
 362                 status = state.status;
 363         }
 364
 365         return status;
 366 }
 367
 368 struct printer_list_exec_state {
 369         void (*fn)(const char *, const char *, void *);
 370         void *private_data;
 371         NTSTATUS status;
 372 };
 373
 374 static int printer_list_exec_fn(struct db_record *rec, void *private_data)
 375 {
 376         struct printer_list_exec_state *state =
 377                         (struct printer_list_exec_state *)private_data;
 378         uint32_t time_h, time_l;
 379         char *name;
 380         char *comment;
 381         int ret;
 382
 383         /* always skip PL_TIMESTAMP_KEY key */
 384         if (strequal((const char *)rec->key.dptr, PL_TIMESTAMP_KEY)) {
 385                 return 0;
 386         }
 387
 388         ret = tdb_unpack(rec->value.dptr, rec->value.dsize,
 389                          PL_DATA_FORMAT, &time_h, &time_l, &name, &comment);
 390         if (ret == -1) {
 391                 DEBUG(1, ("Failed to un pack printer data"));
 392                 state->status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 393                 return -1;
 394         }
 395
 396         state->fn(name, comment, state->private_data);
 397
 398         SAFE_FREE(name);
 399         SAFE_FREE(comment);
 400         return 0;
 401 }
 402
 403 NTSTATUS printer_list_run_fn(void (*fn)(const char *, const char *, void *),
 404                              void *private_data)
 405 {
 406         struct printer_list_exec_state state;
 407         NTSTATUS status;
 408
 409         state.fn = fn;
 410         state.private_data = private_data;
 411         state.status = NT_STATUS_OK;
 412
 413         status = printer_list_traverse(printer_list_exec_fn, &state);
 414         if (NT_STATUS_EQUAL(status, NT_STATUS_UNSUCCESSFUL) &&
 415             !NT_STATUS_IS_OK(state.status)) {
 416                 status = state.status;
 417         }
 418
 419         return status;
 420 }