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                         if ((data[i].type == SDB_TYPE_STRING) && (data[i].data.string))
 160                                 free(data[i].data.string);
 161                         else if ((data[i].type == SDB_TYPE_BINARY)
 162                                         && (data[i].data.binary.datum))
 163                                 free(data[i].data.binary.datum);
 164                 }
 165
 166                 if (status)
 167                         continue;
 168
 169                 ++success;
 170         }
 171
 172         if (! success)
 173                 return -1;
 174         return 0;
 175 } /* sdb_dbi_get_data */
 176
 177 /*
 178  * public API
 179  */
 180
 181 sdb_dbi_options_t *
 182 sdb_dbi_options_create(void)
 183 {
 184         sdb_dbi_options_t *options;
 185
 186         options = malloc(sizeof(*options));
 187         if (! options)
 188                 return NULL;
 189
 190         options->options = NULL;
 191         options->options_num = 0;
 192         return options;
 193 } /* sdb_dbi_options_create */
 194
 195 int
 196 sdb_dbi_options_add(sdb_dbi_options_t *options,
 197                 const char *key, const char *value)
 198 {
 199         sdb_dbi_option_t *new;
 200
 201         if ((! options) || (! key) || (! value))
 202                 return -1;
 203
 204         new = realloc(options->options,
 205                         (options->options_num + 1) * sizeof(*options->options));
 206         if (! new)
 207                 return -1;
 208
 209         options->options = new;
 210         new = options->options + options->options_num;
 211
 212         new->key = strdup(key);
 213         new->value = strdup(value);
 214
 215         if ((! new->key) || (! new->value)) {
 216                 if (new->key)
 217                         free(new->key);
 218                 if (new->value)
 219                         free(new->value);
 220                 return -1;
 221         }
 222
 223         ++options->options_num;
 224         return 0;
 225 } /* sdb_dbi_options_add */
 226
 227 void
 228 sdb_dbi_options_destroy(sdb_dbi_options_t *options)
 229 {
 230         size_t i;
 231
 232         if (! options)
 233                 return;
 234
 235         for (i = 0; i < options->options_num; ++i) {
 236                 sdb_dbi_option_t *opt = options->options + i;
 237
 238                 if (opt->key)
 239                         free(opt->key);
 240                 if (opt->value)
 241                         free(opt->value);
 242         }
 243
 244         if (options->options)
 245                 free(options->options);
 246         options->options = NULL;
 247         options->options_num = 0;
 248         free(options);
 249 } /* sdb_dbi_options_destroy */
 250
 251 sdb_dbi_client_t *
 252 sdb_dbi_client_create(const char *driver, const char *database)
 253 {
 254         sdb_dbi_client_t *client;
 255
 256         if ((! driver) || (! database))
 257                 return NULL;
 258
 259         client = malloc(sizeof(*client));
 260         if (! client)
 261                 return NULL;
 262         memset(client, 0, sizeof(*client));
 263
 264         client->conn = NULL;
 265         client->options = NULL;
 266
 267         client->driver = strdup(driver);
 268         client->database = strdup(database);
 269         if ((! client->driver) || (! client->database)) {
 270                 sdb_dbi_client_destroy(client);
 271                 return NULL;
 272         }
 273         return client;
 274 } /* sdb_dbi_client_create */
 275
 276 int
 277 sdb_dbi_client_set_options(sdb_dbi_client_t *client,
 278                 sdb_dbi_options_t *options)
 279 {
 280         if (! client)
 281                 return -1;
 282
 283         if (client->options)
 284                 sdb_dbi_options_destroy(client->options);
 285         client->options = options;
 286         return 0;
 287 } /* sdb_dbi_client_set_options */
 288
 289 int
 290 sdb_dbi_client_connect(sdb_dbi_client_t *client)
 291 {
 292         dbi_driver driver;
 293         size_t i;
 294
 295         if ((! client) || (! client->driver) || (! client->database))
 296                 return -1;
 297
 298         if (client->conn) {
 299                 dbi_conn_close(client->conn);
 300                 client->conn = NULL;
 301         }
 302
 303         driver = dbi_driver_open(client->driver);
 304         if (! driver) {
 305                 sdb_error_set("dbi: failed to open DBI driver '%s'; "
 306                                 "possibly it's not installed.\n",
 307                                 client->driver);
 308
 309                 sdb_error_append("dbi: known drivers:\n");
 310                 for (driver = dbi_driver_list(NULL); driver;
 311                                 driver = dbi_driver_list(driver)) {
 312                         sdb_error_append("\t- %s\n", dbi_driver_get_name(driver));
 313                 }
 314                 sdb_error_chomp();
 315                 sdb_error_log(SDB_LOG_ERR);
 316                 return -1;
 317         }
 318
 319         client->conn = dbi_conn_open(driver);
 320         if (! client->conn) {
 321                 sdb_log(SDB_LOG_ERR, "dbi: failed to open connection "
 322                                 "object.");
 323                 return -1;
 324         }
 325
 326         if (client->options) {
 327                 for (i = 0; i < client->options->options_num; ++i) {
 328                         const char *opt;
 329
 330                         if (! dbi_conn_set_option(client->conn,
 331                                                 client->options->options[i].key,
 332                                                 client->options->options[i].value))
 333                                 continue;
 334                         /* else: error */
 335
 336                         sdb_error_set("dbi: failed to set option '%s': %s\n",
 337                                         client->options->options[i].key,
 338                                         sdb_dbi_strerror(client->conn));
 339
 340                         sdb_error_append("dbi: known driver options:\n");
 341                         for (opt = dbi_conn_get_option_list(client->conn, NULL); opt;
 342                                         opt = dbi_conn_get_option_list(client->conn, opt))
 343                                 sdb_error_append("\t- %s\n", opt);
 344                         sdb_error_chomp();
 345                         sdb_error_log(SDB_LOG_ERR);
 346
 347                         dbi_conn_close(client->conn);
 348                         client->conn = NULL;
 349                         return -1;
 350                 }
 351         }
 352
 353         if (dbi_conn_set_option(client->conn, "dbname", client->database)) {
 354                 sdb_log(SDB_LOG_ERR, "dbi: failed to set option 'dbname': %s",
 355                                 sdb_dbi_strerror(client->conn));
 356                 dbi_conn_close(client->conn);
 357                 client->conn = NULL;
 358                 return -1;
 359         }
 360
 361         if (dbi_conn_connect(client->conn) < 0) {
 362                 sdb_log(SDB_LOG_ERR, "dbi: failed to connect to database '%s': %s",
 363                                 client->database, sdb_dbi_strerror(client->conn));
 364                 dbi_conn_close(client->conn);
 365                 client->conn = NULL;
 366                 return -1;
 367         }
 368         return 0;
 369 } /* sdb_dbi_client_connect */
 370
 371 int
 372 sdb_dbi_client_check_conn(sdb_dbi_client_t *client)
 373 {
 374         if (! client)
 375                 return -1;
 376
 377         if (! client->conn)
 378                 return sdb_dbi_client_connect(client);
 379
 380         if (dbi_conn_ping(client->conn))
 381                 return 0;
 382         return sdb_dbi_client_connect(client);
 383 } /* sdb_dbi_client_check_conn */
 384
 385 int
 386 sdb_dbi_exec_query(sdb_dbi_client_t *client, const char *query,
 387                 sdb_dbi_data_cb callback, sdb_object_t *user_data, int n, ...)
 388 {
 389         dbi_result res;
 390         unsigned int num_fields;
 391
 392         int status;
 393
 394         if ((! client) || (! client->conn) || (! query))
 395                 return -1;
 396
 397         res = dbi_conn_query(client->conn, query);
 398         if (! res) {
 399                 sdb_log(SDB_LOG_ERR, "dbi: failed to execute query '%s': %s",
 400                                 query, sdb_dbi_strerror(client->conn));
 401                 return -1;
 402         }
 403
 404         if (dbi_result_get_numrows(res) == DBI_ROW_ERROR) {
 405                 sdb_log(SDB_LOG_ERR, "dbi: failed to fetch rows for query "
 406                                 "'%s': %s", query, sdb_dbi_strerror(client->conn));
 407                 dbi_result_free(res);
 408                 return -1;
 409         }
 410
 411         if (dbi_result_get_numrows(res) < 1) { /* no data */
 412                 dbi_result_free(res);
 413                 return 0;
 414         }
 415
 416         num_fields = dbi_result_get_numfields(res);
 417
 418         if (n >= 0) {
 419                 va_list types;
 420                 int i;
 421
 422                 if (n != (int)num_fields) {
 423                         sdb_log(SDB_LOG_ERR, "dbi: number of returned fields (%i) "
 424                                         "does not match the number of requested fields (%i) "
 425                                         "for query '%s'.", num_fields, n, query);
 426                         dbi_result_free(res);
 427                         return -1;
 428                 }
 429
 430                 va_start(types, n);
 431                 status = 0;
 432
 433                 for (i = 0; i < n; ++i) {
 434                         unsigned short field_type = dbi_result_get_field_type_idx(res,
 435                                         (unsigned int)(i + 1));
 436
 437                         unsigned int type = va_arg(types, unsigned int);
 438
 439                         field_type = DBI_TYPE_TO_SC(field_type);
 440
 441                         /* column count starts at 1 */
 442                         if ((unsigned int)field_type != type) {
 443                                 sdb_log(SDB_LOG_ERR, "dbi: type of column '%s' (%u) "
 444                                                 "does not match requested type (%u).",
 445                                                 dbi_result_get_field_name(res, (unsigned int)i + 1),
 446                                                 field_type, type);
 447                                 status = -1;
 448                         }
 449                 }
 450
 451                 va_end(types);
 452
 453                 if (status) {
 454                         dbi_result_free(res);
 455                         return status;
 456                 }
 457         }
 458
 459         if (num_fields < 1) { /* no data */
 460                 dbi_result_free(res);
 461                 return 0;
 462         }
 463
 464         status = sdb_dbi_get_data(client, res, num_fields, callback, user_data);
 465
 466         dbi_result_free(res);
 467         return status;
 468 } /* sdb_dbi_exec_query */
 469
 470 void
 471 sdb_dbi_client_destroy(sdb_dbi_client_t *client)
 472 {
 473         if (! client)
 474                 return;
 475
 476         if (client->driver)
 477                 free(client->driver);
 478         client->driver = NULL;
 479
 480         if (client->database)
 481                 free(client->database);
 482         client->database = NULL;
 483
 484         if (client->conn)
 485                 dbi_conn_close(client->conn);
 486         client->conn = NULL;
 487
 488         if (client->options)
 489                 sdb_dbi_options_destroy(client->options);
 490         client->options = NULL;
 491
 492         free(client);
 493 } /* sdb_dbi_client_destroy */
 494
 495 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 496