src/utils/dbi.c

   1 /*
   2  * syscollector - 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
  30 #include <assert.h>
  31
  32 #include <dbi/dbi.h>
  33
  34 #include <stdarg.h>
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38
  39 /*
  40  * private data types
  41  */
  42
  43 typedef struct {
  44         char *key;
  45         char *value;
  46 } sc_dbi_option_t;
  47
  48 struct sc_dbi_options {
  49         sc_dbi_option_t *options;
  50         size_t options_num;
  51 };
  52
  53 struct sc_dbi_client {
  54         char *driver;
  55         char *database;
  56
  57         dbi_conn conn;
  58
  59         sc_dbi_options_t *options;
  60 };
  61
  62 /*
  63  * private helper functions
  64  */
  65
  66 static const char *
  67 sc_dbi_strerror(dbi_conn conn)
  68 {
  69         const char *errmsg = NULL;
  70         dbi_conn_error(conn, &errmsg);
  71         return errmsg;
  72 } /* sc_dbi_strerror */
  73
  74 static int
  75 sc_dbi_get_field(dbi_result res, unsigned int i,
  76                 int type, sc_dbi_data_t *data)
  77 {
  78         switch (type) {
  79                 case DBI_TYPE_INTEGER:
  80                         data->data.integer = dbi_result_get_longlong_idx(res, i);
  81                         break;
  82                 case DBI_TYPE_DECIMAL:
  83                         data->data.decimal = dbi_result_get_double_idx(res, i);
  84                         break;
  85                 case DBI_TYPE_STRING:
  86                         data->data.string = dbi_result_get_string_idx(res, i);
  87                         break;
  88                 case DBI_TYPE_DATETIME:
  89                         {
  90                                 /* libdbi does not provide any higher resolutions than that */
  91                                 time_t datetime = dbi_result_get_datetime_idx(res, i);
  92                                 data->data.datetime = SECS_TO_SC_TIME(datetime);
  93                         }
  94                         break;
  95                 case DBI_TYPE_BINARY:
  96                         {
  97                                 size_t length = dbi_result_get_field_length_idx(res, i);
  98                                 const unsigned char *datum = dbi_result_get_binary_idx(res, i);
  99                                 data->data.binary.length = length;
 100                                 data->data.binary.datum = datum;
 101                         }
 102                         break;
 103                 default:
 104                         fprintf(stderr, "dbi: Unexpected type %i while "
 105                                         "parsing query result.\n", type);
 106                         return -1;
 107         }
 108
 109         data->type = type;
 110         return 0;
 111 } /* sc_dbi_get_field */
 112
 113 static int
 114 sc_dbi_get_data(sc_dbi_client_t *client, dbi_result res,
 115                 unsigned int num_fields, sc_dbi_data_cb callback)
 116 {
 117         sc_dbi_data_t data[num_fields];
 118         int types[num_fields];
 119         unsigned int i;
 120
 121         unsigned long long num_rows;
 122         unsigned long long success = 0, n;
 123
 124         assert(client && res && callback);
 125         assert(num_fields > 0);
 126
 127         for (i = 0; i < num_fields; ++i) {
 128                 types[i] = dbi_result_get_field_type_idx(res, i + 1);
 129                 if (types[i] == DBI_TYPE_ERROR) {
 130                         fprintf(stderr, "dbi: failed to fetch data: %s\n",
 131                                         sc_dbi_strerror(client->conn));
 132                         return -1;
 133                 }
 134         }
 135
 136         num_rows = dbi_result_get_numrows(res);
 137         if (num_rows < 1)
 138                 return -1;
 139
 140         for (n = 0; n < num_rows; ++n) {
 141                 if (! dbi_result_seek_row(res, n + 1)) {
 142                         fprintf(stderr, "dbi: Failed to retrieve row %llu: %s\n",
 143                                         n, sc_dbi_strerror(client->conn));
 144                         continue;
 145                 }
 146
 147                 for (i = 0; i < num_fields; ++i)
 148                         if (sc_dbi_get_field(res, (unsigned int)(i + 1),
 149                                                 types[i], &data[i]))
 150                                 continue;
 151
 152                 if (callback(client, num_fields, data))
 153                         continue;
 154
 155                 ++success;
 156         }
 157
 158         if (! success)
 159                 return -1;
 160         return 0;
 161 } /* sc_dbi_get_data */
 162
 163 /*
 164  * public API
 165  */
 166
 167 sc_dbi_options_t *
 168 sc_dbi_options_create(void)
 169 {
 170         sc_dbi_options_t *options;
 171
 172         options = malloc(sizeof(options));
 173         if (! options)
 174                 return NULL;
 175
 176         options->options = NULL;
 177         options->options_num = 0;
 178         return options;
 179 } /* sc_dbi_options_create */
 180
 181 int
 182 sc_dbi_options_add(sc_dbi_options_t *options,
 183                 const char *key, const char *value)
 184 {
 185         sc_dbi_option_t *new;
 186
 187         if ((! options) || (! key) || (! value))
 188                 return -1;
 189
 190         new = realloc(options->options,
 191                         (options->options_num + 1) * sizeof(*options->options));
 192         if (! new)
 193                 return -1;
 194
 195         options->options = new;
 196         new = options->options + options->options_num;
 197
 198         new->key = strdup(key);
 199         new->value = strdup(value);
 200
 201         if ((! new->key) || (! new->value)) {
 202                 if (new->key)
 203                         free(new->key);
 204                 if (new->value)
 205                         free(new->value);
 206                 return -1;
 207         }
 208
 209         ++options->options_num;
 210         return 0;
 211 } /* sc_dbi_options_add */
 212
 213 void
 214 sc_dbi_options_destroy(sc_dbi_options_t *options)
 215 {
 216         size_t i;
 217
 218         if (! options)
 219                 return;
 220
 221         for (i = 0; i < options->options_num; ++i) {
 222                 sc_dbi_option_t *opt = options->options + i;
 223
 224                 if (opt->key)
 225                         free(opt->key);
 226                 if (opt->value)
 227                         free(opt->value);
 228         }
 229
 230         if (options->options)
 231                 free(options->options);
 232         options->options = NULL;
 233         options->options_num = 0;
 234         free(options);
 235 } /* sc_dbi_options_destroy */
 236
 237 sc_dbi_client_t *
 238 sc_dbi_client_create(const char *driver, const char *database)
 239 {
 240         sc_dbi_client_t *client;
 241
 242         if ((! driver) || (! database))
 243                 return NULL;
 244
 245         client = malloc(sizeof(*client));
 246         if (! client)
 247                 return NULL;
 248         memset(client, 0, sizeof(*client));
 249
 250         client->conn = NULL;
 251         client->options = NULL;
 252
 253         client->driver = strdup(driver);
 254         client->database = strdup(database);
 255         if ((! client->driver) || (! client->database)) {
 256                 sc_dbi_client_destroy(client);
 257                 return NULL;
 258         }
 259         return client;
 260 } /* sc_dbi_client_create */
 261
 262 int
 263 sc_dbi_client_set_options(sc_dbi_client_t *client,
 264                 sc_dbi_options_t *options)
 265 {
 266         if (! client)
 267                 return -1;
 268
 269         if (client->options)
 270                 sc_dbi_options_destroy(client->options);
 271         client->options = options;
 272         return 0;
 273 } /* sc_dbi_client_set_options */
 274
 275 int
 276 sc_dbi_client_connect(sc_dbi_client_t *client)
 277 {
 278         dbi_driver driver;
 279         size_t i;
 280
 281         if ((! client) || (! client->driver) || (! client->database))
 282                 return -1;
 283
 284         if (client->conn)
 285                 dbi_conn_close(client->conn);
 286
 287         driver = dbi_driver_open(client->driver);
 288         if (! driver) {
 289                 fprintf(stderr, "dbi: failed to open DBI driver '%s'; "
 290                                 "possibly it's not installed.\n",
 291                                 client->driver);
 292
 293                 fprintf(stderr, "dbi: known drivers:\n");
 294                 for (driver = dbi_driver_list(NULL); driver;
 295                                 driver = dbi_driver_list(driver)) {
 296                         fprintf(stderr, "\t- %s\n", dbi_driver_get_name(driver));
 297                 }
 298                 return -1;
 299         }
 300
 301         client->conn = dbi_conn_open(driver);
 302         if (! client->conn) {
 303                 fprintf(stderr, "dbi: failed to open connection object.\n");
 304                 return -1;
 305         }
 306
 307         if (client->options) {
 308                 for (i = 0; i < client->options->options_num; ++i) {
 309                         const char *opt;
 310
 311                         if (! dbi_conn_set_option(client->conn,
 312                                                 client->options->options[i].key,
 313                                                 client->options->options[i].value))
 314                                 continue;
 315                         /* else: error */
 316
 317                         fprintf(stderr, "dbi: failed to set option '%s': %s\n",
 318                                         client->options->options[i].key,
 319                                         sc_dbi_strerror(client->conn));
 320
 321                         fprintf(stderr, "dbi: known driver options:\n");
 322                         for (opt = dbi_conn_get_option_list(client->conn, NULL); opt;
 323                                         opt = dbi_conn_get_option_list(client->conn, opt))
 324                                 fprintf(stderr, "\t- %s\n", opt);
 325
 326                         dbi_conn_close(client->conn);
 327                         return -1;
 328                 }
 329         }
 330
 331         if (dbi_conn_set_option(client->conn, "dbname", client->database)) {
 332                 fprintf(stderr, "dbi: failed to set option 'dbname': %s\n",
 333                                 sc_dbi_strerror(client->conn));
 334                 dbi_conn_close(client->conn);
 335                 return -1;
 336         }
 337
 338         if (dbi_conn_connect(client->conn) < 0) {
 339                 fprintf(stderr, "dbi: failed to connect to database '%s': %s\n",
 340                                 client->database, sc_dbi_strerror(client->conn));
 341                 dbi_conn_close(client->conn);
 342                 return -1;
 343         }
 344         return 0;
 345 } /* sc_dbi_client_connect */
 346
 347 int
 348 sc_dbi_exec_query(sc_dbi_client_t *client, const char *query,
 349                 sc_dbi_data_cb callback, int n, ...)
 350 {
 351         dbi_result res;
 352         unsigned int num_fields;
 353
 354         int status;
 355
 356         if ((! client) || (! query))
 357                 return -1;
 358
 359         res = dbi_conn_query(client->conn, query);
 360         if (! res) {
 361                 fprintf(stderr, "dbi: failed to execute query '%s': %s\n",
 362                                 query, sc_dbi_strerror(client->conn));
 363                 return -1;
 364         }
 365
 366         if (dbi_result_get_numrows(res) == DBI_ROW_ERROR) {
 367                 fprintf(stderr, "dbi: failed to fetch rows for query '%s': %s\n",
 368                                 query, sc_dbi_strerror(client->conn));
 369                 dbi_result_free(res);
 370                 return -1;
 371         }
 372
 373         if (dbi_result_get_numrows(res) < 1) { /* no data */
 374                 dbi_result_free(res);
 375                 return 0;
 376         }
 377
 378         num_fields = dbi_result_get_numfields(res);
 379
 380         if (n >= 0) {
 381                 va_list types;
 382                 int i;
 383
 384                 if (n != (int)num_fields) {
 385                         fprintf(stderr, "dbi: number of returned fields (%i) does not "
 386                                         "match the number of requested fields (%i) "
 387                                         "for query '%s'.\n", num_fields, n, query);
 388                         dbi_result_free(res);
 389                         return -1;
 390                 }
 391
 392                 va_start(types, n);
 393                 status = 0;
 394
 395                 for (i = 0; i < n; ++i) {
 396                         unsigned short field_type = dbi_result_get_field_type_idx(res,
 397                                         (unsigned int)(i + 1));
 398
 399                         unsigned int type = va_arg(types, unsigned int);
 400
 401                         /* column count starts at 1 */
 402                         if ((unsigned int)field_type != type) {
 403                                 fprintf(stderr, "dbi: type of column '%s' (%u) does not match "
 404                                                 "requested type (%u).\n",
 405                                                 dbi_result_get_field_name(res, (unsigned int)i + 1),
 406                                                 field_type, type);
 407                                 status = -1;
 408                         }
 409                 }
 410
 411                 va_end(types);
 412
 413                 if (status) {
 414                         dbi_result_free(res);
 415                         return status;
 416                 }
 417         }
 418
 419         if (num_fields < 1) { /* no data */
 420                 dbi_result_free(res);
 421                 return 0;
 422         }
 423
 424         status = sc_dbi_get_data(client, res, num_fields, callback);
 425
 426         dbi_result_free(res);
 427         return status;
 428 } /* sc_dbi_exec_query */
 429
 430 void
 431 sc_dbi_client_destroy(sc_dbi_client_t *client)
 432 {
 433         if (! client)
 434                 return;
 435
 436         if (client->driver)
 437                 free(client->driver);
 438         client->driver = NULL;
 439
 440         if (client->database)
 441                 free(client->database);
 442         client->database = NULL;
 443
 444         if (client->conn)
 445                 dbi_conn_close(client->conn);
 446
 447         if (client->options)
 448                 sc_dbi_options_destroy(client->options);
 449         client->options = NULL;
 450
 451         free(client);
 452 } /* sc_dbi_client_destroy */
 453
 454 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 455