src/my/my.c

   1 /*
   2      This file is part of GNUnet
   3      Copyright (C) 2016, 2018 GNUnet e.V.
   4
   5      GNUnet is free software: you can redistribute it and/or modify it
   6      under the terms of the GNU Affero General Public License as published
   7      by the Free Software Foundation, either version 3 of the License,
   8      or (at your option) any later version.
   9
  10      GNUnet is distributed in the hope that it will be useful, but
  11      WITHOUT ANY WARRANTY; without even the implied warranty of
  12      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13      Affero General Public License for more details.
  14
  15      You should have received a copy of the GNU Affero General Public License
  16      along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17
  18      SPDX-License-Identifier: AGPL3.0-or-later
  19  */
  20 /**
  21  * @file my/my.c
  22  * @brief library to help with access to a MySQL database
  23  * @author Christophe Genevey
  24  * @author Christian Grothoff
  25  */
  26 #include "platform.h"
  27 #include <mysql/mysql.h>
  28 #include "gnunet_my_lib.h"
  29
  30
  31 /**
  32  * Run a prepared SELECT statement.
  33  *
  34  * @param mc mysql context
  35  * @param sh handle to SELECT statment
  36  * @param params parameters to the statement
  37  * @return
  38  #GNUNET_YES if we can prepare all statement
  39  #GNUNET_SYSERR if we can't prepare all statement
  40  */
  41 int
  42 GNUNET_MY_exec_prepared(struct GNUNET_MYSQL_Context *mc,
  43                         struct GNUNET_MYSQL_StatementHandle *sh,
  44                         struct GNUNET_MY_QueryParam *params)
  45 {
  46   const struct GNUNET_MY_QueryParam *p;
  47   unsigned int num;
  48   MYSQL_STMT *stmt;
  49
  50   num = 0;
  51   for (unsigned int i = 0; NULL != params[i].conv; i++)
  52     num += params[i].num_params;
  53   {
  54     MYSQL_BIND qbind[num];
  55     unsigned int off;
  56
  57     memset(qbind,
  58            0,
  59            sizeof(qbind));
  60     off = 0;
  61     for (unsigned int i = 0; NULL != (p = &params[i])->conv; i++)
  62       {
  63         if (GNUNET_OK !=
  64             p->conv(p->conv_cls,
  65                     p,
  66                     &qbind[off]))
  67           {
  68             GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
  69                        "Conversion for MySQL query failed at offset %u\n",
  70                        i);
  71             return GNUNET_SYSERR;
  72           }
  73         off += p->num_params;
  74       }
  75     stmt = GNUNET_MYSQL_statement_get_stmt(sh);
  76     if (mysql_stmt_bind_param(stmt,
  77                               qbind))
  78       {
  79         GNUNET_log_from(GNUNET_ERROR_TYPE_ERROR,
  80                         "my",
  81                         _("`%s' failed at %s:%d with error: %s\n"),
  82                         "mysql_stmt_bind_param",
  83                         __FILE__, __LINE__,
  84                         mysql_stmt_error(stmt));
  85         GNUNET_MYSQL_statements_invalidate(mc);
  86         return GNUNET_SYSERR;
  87       }
  88
  89     if (mysql_stmt_execute(stmt))
  90       {
  91         GNUNET_log_from(GNUNET_ERROR_TYPE_ERROR,
  92                         "my",
  93                         _("`%s' failed at %s:%d with error: %s\n"),
  94                         "mysql_stmt_execute", __FILE__, __LINE__,
  95                         mysql_stmt_error(stmt));
  96         GNUNET_MYSQL_statements_invalidate(mc);
  97         return GNUNET_SYSERR;
  98       }
  99     GNUNET_MY_cleanup_query(params,
 100                             qbind);
 101   }
 102   return GNUNET_OK;
 103 }
 104
 105
 106 /**
 107  * Free all memory that was allocated in @a qp during
 108  * #GNUNET_MY_exec_prepared().
 109  *
 110  * @param qp query specification to clean up
 111  * @param qbind array of parameter to clean up
 112  */
 113 void
 114 GNUNET_MY_cleanup_query(struct GNUNET_MY_QueryParam *qp,
 115                         MYSQL_BIND *qbind)
 116 {
 117   for (unsigned int i = 0; NULL != qp[i].conv; i++)
 118     if (NULL != qp[i].cleaner)
 119       qp[i].cleaner(qp[i].conv_cls,
 120                     &qbind[i]);
 121 }
 122
 123
 124 /**
 125  * Extract results from a query result according to the given
 126  * specification.  Always fetches the next row.
 127  *
 128  * @param sh statement that returned results
 129  * @param rs specification to extract for
 130  * @return
 131  *  #GNUNET_YES if all results could be extracted
 132  *  #GNUNET_NO if there is no more data in the result set
 133  *  #GNUNET_SYSERR if a result was invalid
 134  */
 135 int
 136 GNUNET_MY_extract_result(struct GNUNET_MYSQL_StatementHandle *sh,
 137                          struct GNUNET_MY_ResultSpec *rs)
 138 {
 139   unsigned int num_fields;
 140   int ret;
 141   MYSQL_STMT *stmt;
 142
 143   stmt = GNUNET_MYSQL_statement_get_stmt(sh);
 144   if (NULL == stmt)
 145     {
 146       GNUNET_break(0);
 147       return GNUNET_SYSERR;
 148     }
 149   if (NULL == rs)
 150     {
 151       mysql_stmt_free_result(stmt);
 152       return GNUNET_NO;
 153     }
 154
 155   num_fields = 0;
 156   for (unsigned int i = 0; NULL != rs[i].pre_conv; i++)
 157     num_fields += rs[i].num_fields;
 158
 159   if (mysql_stmt_field_count(stmt) != num_fields)
 160     {
 161       GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
 162                  "Number of fields mismatch between SQL result and result specification\n");
 163       return GNUNET_SYSERR;
 164     }
 165
 166   {
 167     MYSQL_BIND result[num_fields];
 168     unsigned int field_off;
 169
 170     memset(result, 0, sizeof(MYSQL_BIND) * num_fields);
 171     field_off = 0;
 172     for (unsigned int i = 0; NULL != rs[i].pre_conv; i++)
 173       {
 174         struct GNUNET_MY_ResultSpec *rp = &rs[i];
 175
 176         if (GNUNET_OK !=
 177             rp->pre_conv(rp->conv_cls,
 178                          rp,
 179                          stmt,
 180                          field_off,
 181                          &result[field_off]))
 182
 183           {
 184             GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
 185                        "Pre-conversion for MySQL result failed at offset %u\n",
 186                        i);
 187             return GNUNET_SYSERR;
 188           }
 189         field_off += rp->num_fields;
 190       }
 191
 192     if (mysql_stmt_bind_result(stmt, result))
 193       {
 194         GNUNET_log_from(GNUNET_ERROR_TYPE_ERROR,
 195                         "my",
 196                         _("%s failed at %s:%d with error: %s\n"),
 197                         "mysql_stmt_bind_result",
 198                         __FILE__, __LINE__,
 199                         mysql_stmt_error(stmt));
 200         return GNUNET_SYSERR;
 201       }
 202 #if TEST_OPTIMIZATION
 203     (void)mysql_stmt_store_result(stmt);
 204 #endif
 205     ret = mysql_stmt_fetch(stmt);
 206     if (MYSQL_NO_DATA == ret)
 207       {
 208         mysql_stmt_free_result(stmt);
 209         return GNUNET_NO;
 210       }
 211     if (1 == ret)
 212       {
 213         GNUNET_log_from(GNUNET_ERROR_TYPE_ERROR,
 214                         "my",
 215                         _("%s failed at %s:%d with error: %s\n"),
 216                         "mysql_stmt_fetch",
 217                         __FILE__, __LINE__,
 218                         mysql_stmt_error(stmt));
 219         GNUNET_MY_cleanup_result(rs);
 220         mysql_stmt_free_result(stmt);
 221         return GNUNET_SYSERR;
 222       }
 223     field_off = 0;
 224     for (unsigned int i = 0; NULL != rs[i].post_conv; i++)
 225       {
 226         struct GNUNET_MY_ResultSpec *rp = &rs[i];
 227
 228         if (NULL != rp->post_conv)
 229           if (GNUNET_OK !=
 230               rp->post_conv(rp->conv_cls,
 231                             rp,
 232                             stmt,
 233                             field_off,
 234                             &result[field_off]))
 235             {
 236               GNUNET_log(GNUNET_ERROR_TYPE_INFO,
 237                          "Post-conversion for MySQL result failed at offset %u\n",
 238                          i);
 239               mysql_stmt_free_result(stmt);
 240               GNUNET_MY_cleanup_result(rs);
 241               return GNUNET_SYSERR;
 242             }
 243         field_off += rp->num_fields;
 244       }
 245   }
 246   return GNUNET_OK;
 247 }
 248
 249
 250 /**
 251  * Free all memory that was allocated in @a rs during
 252  * #GNUNET_MY_extract_result().
 253  *
 254  * @param rs result specification to clean up
 255  */
 256 void
 257 GNUNET_MY_cleanup_result(struct GNUNET_MY_ResultSpec *rs)
 258 {
 259   for (unsigned int i = 0; NULL != rs[i].post_conv; i++)
 260     if (NULL != rs[i].cleaner)
 261       rs[i].cleaner(rs[i].conv_cls,
 262                     &rs[i]);
 263 }
 264
 265
 266 /* end of my.c */