src/utils/dbi.c

   1 /*
   2  * SysDB - src/utils/dbi.c
   3  * Copyright (C) 2012 Sebastian 'tokkee' Harl <sh@tokkee.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  16  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  17  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  18  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
  19  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include "utils/dbi.h"
  29 #include "utils/error.h"
  30
  31 #include <assert.h>
  32
  33 #include <dbi/dbi.h>
  34
  35 #include <stdarg.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39
  40 /*
  41  * private data types
  42  */
  43
  44 typedef struct {
  45         char *key;
  46         char *value;
  47 } sdb_dbi_option_t;
  48
  49 struct sdb_dbi_options {
  50         sdb_dbi_option_t *options;
  51         size_t options_num;
  52 };
  53
  54 struct sdb_dbi_client {
  55         char *driver;
  56         char *database;
  57
  58         dbi_conn conn;
  59
  60         sdb_dbi_options_t *options;
  61 };
  62
  63 /*
  64  * private helper functions
  65  */
  66
  67 static const char *
  68 sdb_dbi_strerror(dbi_conn conn)
  69 {
  70         const char *errmsg = NULL;
  71         dbi_conn_error(conn, &errmsg);
  72         return errmsg;
  73 } /* sdb_dbi_strerror */
  74
  75 static int
  76 sdb_dbi_get_field(dbi_result res, unsigned int i,
  77                 int type, sdb_data_t *data)
  78 {
  79         switch (type) {
  80                 case SDB_TYPE_INTEGER:
  81                         data->data.integer = dbi_result_get_longlong_idx(res, i);
  82                         break;
  83                 case SDB_TYPE_DECIMAL:
  84                         data->data.decimal = dbi_result_get_double_idx(res, i);
  85                         break;
  86                 case SDB_TYPE_STRING:
  87                         data->data.string = dbi_result_get_string_copy_idx(res, i);
  88                         break;
  89                 case SDB_TYPE_DATETIME:
  90                         {
  91                                 /* libdbi does not provide any higher resolutions than that */
  92                                 time_t datetime = dbi_result_get_datetime_idx(res, i);
  93                                 data->data.datetime = SECS_TO_SDB_TIME(datetime);
  94                         }
  95                         break;
  96                 case SDB_TYPE_BINARY:
  97                         {
  98                                 size_t length = dbi_result_get_field_length_idx(res, i);
  99                                 unsigned char *datum = dbi_result_get_binary_copy_idx(res, i);
 100                                 data->data.binary.length = length;
 101                                 data->data.binary.datum = datum;
 102                         }
 103                         break;
 104                 default:
 105                         sdb_log(SDB_LOG_ERR, "dbi: Unexpected type %i while "
 106                                         "parsing query result.", type);
 107                         return -1;
 108         }
 109
 110         data->type = type;
 111         return 0;
 112 } /* sdb_dbi_get_field */
 113
 114 static int
 115 sdb_dbi_get_data(sdb_dbi_client_t *client, dbi_result res,
 116                 unsigned int num_fields, sdb_dbi_data_cb callback,
 117                 sdb_object_t *user_data)
 118 {
 119         sdb_data_t data[num_fields];
 120         int types[num_fields];
 121         unsigned int i;
 122
 123         unsigned long long num_rows;
 124         unsigned long long success = 0, n;
 125
 126         assert(client && res && callback);
 127         assert(num_fields > 0);
 128
 129         for (i = 0; i < num_fields; ++i) {
 130                 types[i] = dbi_result_get_field_type_idx(res, i + 1);
 131                 if (types[i] == DBI_TYPE_ERROR) {
 132                         sdb_log(SDB_LOG_ERR, "dbi: failed to fetch data: %s",
 133                                         sdb_dbi_strerror(client->conn));
 134                         return -1;
 135                 }
 136                 types[i] = DBI_TYPE_TO_SC(types[i]);
 137         }
 138
 139         num_rows = dbi_result_get_numrows(res);
 140         if (num_rows < 1)
 141                 return -1;
 142
 143         for (n = 0; n < num_rows; ++n) {
 144                 int status;
 145
 146                 if (! dbi_result_seek_row(res, n + 1)) {
 147                         sdb_log(SDB_LOG_ERR, "dbi: Failed to retrieve row %llu: %s",
 148                                         n, sdb_dbi_strerror(client->conn));
 149                         continue;
 150                 }
 151
 152                 for (i = 0; i < num_fields; ++i)
 153                         if (sdb_dbi_get_field(res, (unsigned int)(i + 1),
 154                                                 types[i], &data[i]))
 155                                 continue;
 156
 157                 status = callback(client, num_fields, data, user_data);
 158                 for (i = 0; i < num_fields; ++i)
 159                         sdb_data_free_datum(&data[i]);
 160
 161                 if (status)
 162                         continue;
 163
 164                 ++success;
 165         }
 166
 167         if (! success)
 168                 return -1;
 169         return 0;
 170 } /* sdb_dbi_get_data */
 171
 172 /*
 173  * public API
 174  */
 175
 176 sdb_dbi_options_t *
 177 sdb_dbi_options_create(void)
 178 {
 179         sdb_dbi_options_t *options;
 180
 181         options = malloc(sizeof(*options));
 182         if (! options)
 183                 return NULL;
 184
 185         options->options = NULL;
 186         options->options_num = 0;
 187         return options;
 188 } /* sdb_dbi_options_create */
 189
 190 int
 191 sdb_dbi_options_add(sdb_dbi_options_t *options,
 192                 const char *key, const char *value)
 193 {
 194         sdb_dbi_option_t *new;
 195
 196         if ((! options) || (! key) || (! value))
 197                 return -1;
 198
 199         new = realloc(options->options,
 200                         (options->options_num + 1) * sizeof(*options->options));
 201         if (! new)
 202                 return -1;
 203
 204         options->options = new;
 205         new = options->options + options->options_num;
 206
 207         new->key = strdup(key);
 208         new->value = strdup(value);
 209
 210         if ((! new->key) || (! new->value)) {
 211                 if (new->key)
 212                         free(new->key);
 213                 if (new->value)
 214                         free(new->value);
 215                 return -1;
 216         }
 217
 218         ++options->options_num;
 219         return 0;
 220 } /* sdb_dbi_options_add */
 221
 222 void
 223 sdb_dbi_options_destroy(sdb_dbi_options_t *options)
 224 {
 225         size_t i;
 226
 227         if (! options)
 228                 return;
 229
 230         for (i = 0; i < options->options_num; ++i) {
 231                 sdb_dbi_option_t *opt = options->options + i;
 232
 233                 if (opt->key)
 234                         free(opt->key);
 235                 if (opt->value)
 236                         free(opt->value);
 237         }
 238
 239         if (options->options)
 240                 free(options->options);
 241         options->options = NULL;
 242         options->options_num = 0;
 243         free(options);
 244 } /* sdb_dbi_options_destroy */
 245
 246 sdb_dbi_client_t *
 247 sdb_dbi_client_create(const char *driver, const char *database)
 248 {
 249         sdb_dbi_client_t *client;
 250
 251         if ((! driver) || (! database))
 252                 return NULL;
 253
 254         client = malloc(sizeof(*client));
 255         if (! client)
 256                 return NULL;
 257         memset(client, 0, sizeof(*client));
 258
 259         client->conn = NULL;
 260         client->options = NULL;
 261
 262         client->driver = strdup(driver);
 263         client->database = strdup(database);
 264         if ((! client->driver) || (! client->database)) {
 265                 sdb_dbi_client_destroy(client);
 266                 return NULL;
 267         }
 268         return client;
 269 } /* sdb_dbi_client_create */
 270
 271 int
 272 sdb_dbi_client_set_options(sdb_dbi_client_t *client,
 273                 sdb_dbi_options_t *options)
 274 {
 275         if (! client)
 276                 return -1;
 277
 278         if (client->options)
 279                 sdb_dbi_options_destroy(client->options);
 280         client->options = options;
 281         return 0;
 282 } /* sdb_dbi_client_set_options */
 283
 284 int
 285 sdb_dbi_client_connect(sdb_dbi_client_t *client)
 286 {
 287         dbi_driver driver;
 288         size_t i;
 289
 290         if ((! client) || (! client->driver) || (! client->database))
 291                 return -1;
 292
 293         if (client->conn) {
 294                 dbi_conn_close(client->conn);
 295                 client->conn = NULL;
 296         }
 297
 298         driver = dbi_driver_open(client->driver);
 299         if (! driver) {
 300                 sdb_error_set("dbi: failed to open DBI driver '%s'; "
 301                                 "possibly it's not installed.\n",
 302                                 client->driver);
 303
 304                 sdb_error_append("dbi: known drivers:\n");
 305                 for (driver = dbi_driver_list(NULL); driver;
 306                                 driver = dbi_driver_list(driver)) {
 307                         sdb_error_append("\t- %s\n", dbi_driver_get_name(driver));
 308                 }
 309                 sdb_error_chomp();
 310                 sdb_error_log(SDB_LOG_ERR);
 311                 return -1;
 312         }
 313
 314         client->conn = dbi_conn_open(driver);
 315         if (! client->conn) {
 316                 sdb_log(SDB_LOG_ERR, "dbi: failed to open connection "
 317                                 "object.");
 318                 return -1;
 319         }
 320
 321         if (client->options) {
 322                 for (i = 0; i < client->options->options_num; ++i) {
 323                         const char *opt;
 324
 325                         if (! dbi_conn_set_option(client->conn,
 326                                                 client->options->options[i].key,
 327                                                 client->options->options[i].value))
 328                                 continue;
 329                         /* else: error */
 330
 331                         sdb_error_set("dbi: failed to set option '%s': %s\n",
 332                                         client->options->options[i].key,
 333                                         sdb_dbi_strerror(client->conn));
 334
 335                         sdb_error_append("dbi: known driver options:\n");
 336                         for (opt = dbi_conn_get_option_list(client->conn, NULL); opt;
 337                                         opt = dbi_conn_get_option_list(client->conn, opt))
 338                                 sdb_error_append("\t- %s\n", opt);
 339                         sdb_error_chomp();
 340                         sdb_error_log(SDB_LOG_ERR);
 341
 342                         dbi_conn_close(client->conn);
 343                         client->conn = NULL;
 344                         return -1;
 345                 }
 346         }
 347
 348         if (dbi_conn_set_option(client->conn, "dbname", client->database)) {
 349                 sdb_log(SDB_LOG_ERR, "dbi: failed to set option 'dbname': %s",
 350                                 sdb_dbi_strerror(client->conn));
 351                 dbi_conn_close(client->conn);
 352                 client->conn = NULL;
 353                 return -1;
 354         }
 355
 356         if (dbi_conn_connect(client->conn) < 0) {
 357                 sdb_log(SDB_LOG_ERR, "dbi: failed to connect to database '%s': %s",
 358                                 client->database, sdb_dbi_strerror(client->conn));
 359                 dbi_conn_close(client->conn);
 360                 client->conn = NULL;
 361                 return -1;
 362         }
 363         return 0;
 364 } /* sdb_dbi_client_connect */
 365
 366 int
 367 sdb_dbi_client_check_conn(sdb_dbi_client_t *client)
 368 {
 369         if (! client)
 370                 return -1;
 371
 372         if (! client->conn)
 373                 return sdb_dbi_client_connect(client);
 374
 375         if (dbi_conn_ping(client->conn))
 376                 return 0;
 377         return sdb_dbi_client_connect(client);
 378 } /* sdb_dbi_client_check_conn */
 379
 380 int
 381 sdb_dbi_exec_query(sdb_dbi_client_t *client, const char *query,
 382                 sdb_dbi_data_cb callback, sdb_object_t *user_data, int n, ...)
 383 {
 384         dbi_result res;
 385         unsigned int num_fields;
 386
 387         int status;
 388
 389         if ((! client) || (! client->conn) || (! query))
 390                 return -1;
 391
 392         res = dbi_conn_query(client->conn, query);
 393         if (! res) {
 394                 sdb_log(SDB_LOG_ERR, "dbi: failed to execute query '%s': %s",
 395                                 query, sdb_dbi_strerror(client->conn));
 396                 return -1;
 397         }
 398
 399         if (dbi_result_get_numrows(res) == DBI_ROW_ERROR) {
 400                 sdb_log(SDB_LOG_ERR, "dbi: failed to fetch rows for query "
 401                                 "'%s': %s", query, sdb_dbi_strerror(client->conn));
 402                 dbi_result_free(res);
 403                 return -1;
 404         }
 405
 406         if (dbi_result_get_numrows(res) < 1) { /* no data */
 407                 dbi_result_free(res);
 408                 return 0;
 409         }
 410
 411         num_fields = dbi_result_get_numfields(res);
 412
 413         if (n >= 0) {
 414                 va_list types;
 415                 int i;
 416
 417                 if (n != (int)num_fields) {
 418                         sdb_log(SDB_LOG_ERR, "dbi: number of returned fields (%i) "
 419                                         "does not match the number of requested fields (%i) "
 420                                         "for query '%s'.", num_fields, n, query);
 421                         dbi_result_free(res);
 422                         return -1;
 423                 }
 424
 425                 va_start(types, n);
 426                 status = 0;
 427
 428                 for (i = 0; i < n; ++i) {
 429                         unsigned short field_type = dbi_result_get_field_type_idx(res,
 430                                         (unsigned int)(i + 1));
 431
 432                         unsigned int type = va_arg(types, unsigned int);
 433
 434                         field_type = DBI_TYPE_TO_SC(field_type);
 435
 436                         /* column count starts at 1 */
 437                         if ((unsigned int)field_type != type) {
 438                                 sdb_log(SDB_LOG_ERR, "dbi: type of column '%s' (%u) "
 439                                                 "does not match requested type (%u).",
 440                                                 dbi_result_get_field_name(res, (unsigned int)i + 1),
 441                                                 field_type, type);
 442                                 status = -1;
 443                         }
 444                 }
 445
 446                 va_end(types);
 447
 448                 if (status) {
 449                         dbi_result_free(res);
 450                         return status;
 451                 }
 452         }
 453
 454         if (num_fields < 1) { /* no data */
 455                 dbi_result_free(res);
 456                 return 0;
 457         }
 458
 459         status = sdb_dbi_get_data(client, res, num_fields, callback, user_data);
 460
 461         dbi_result_free(res);
 462         return status;
 463 } /* sdb_dbi_exec_query */
 464
 465 void
 466 sdb_dbi_client_destroy(sdb_dbi_client_t *client)
 467 {
 468         if (! client)
 469                 return;
 470
 471         if (client->driver)
 472                 free(client->driver);
 473         client->driver = NULL;
 474
 475         if (client->database)
 476                 free(client->database);
 477         client->database = NULL;
 478
 479         if (client->conn)
 480                 dbi_conn_close(client->conn);
 481         client->conn = NULL;
 482
 483         if (client->options)
 484                 sdb_dbi_options_destroy(client->options);
 485         client->options = NULL;
 486
 487         free(client);
 488 } /* sdb_dbi_client_destroy */
 489
 490 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 491