modules/ud/ud_serial.c

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DEFINITIONS

This source file includes following functions.
  1. UD_lock_serial
  2. UD_unlock_serial
  3. UD_create_serial
  4. UD_comrol_serial

   1 /***************************************
   2 
   3   Functions for handling serials  
   4 
   5   Status: NOT REVUED, NOT TESTED
   6 
   7  Author(s):       Andrei Robachevsky
   8 
   9   ******************/ /******************
  10   Modification History:
  11         andrei (08/02/2000) Created.
  12   ******************/ /******************
  13   Copyright (c) 2000,2001,2002                    RIPE NCC
  14  
  15   All Rights Reserved
  16   
  17   Permission to use, copy, modify, and distribute this software and its
  18   documentation for any purpose and without fee is hereby granted,
  19   provided that the above copyright notice appear in all copies and that
  20   both that copyright notice and this permission notice appear in
  21   supporting documentation, and that the name of the author not be
  22   used in advertising or publicity pertaining to distribution of the
  23   software without specific, written prior permission.
  24   
  25   THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
  26   ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS; IN NO EVENT SHALL
  27   AUTHOR BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
  28   DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
  29   AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  30   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  31  ***************************************/
  32 
  33 #include "rip.h"
  34 
  35 /************************************************************
  36 * int UD_lock/unlock_serial()                               *
  37 *                                                           *
  38 * Performs lockind/unlocking of the relevant tables         *
  39 *                                                           *
  40 * Returns:                                                  *
  41 * 0 - success                                               *
  42 * Non-zero if error occured (XXX dies now)                  *
  43 *                                                           *
  44 ************************************************************/
  45 int UD_lock_serial(Transaction_t *tr)
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  46 {
  47 int sql_err;
  48 
  49 /* lock all tables we are going to update and commit */ 
  50 /* this also includes transaction_rec table, as we update the status */
  51    sql_err=SQ_execute_query(tr->sql_connection, "LOCK TABLES serials WRITE, failed_transaction WRITE, transaction_rec WRITE ", NULL);
  52    if (sql_err) { 
  53         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), "LOCK TABLES serials WRITE, failed_transaction WRITE, transaction_rec WRITE ");
  54         die;
  55     }
  56  return(sql_err);
  57 }
  58 
  59 int UD_unlock_serial(Transaction_t *tr)
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  60 {
  61 int sql_err;
  62         
  63    sql_err=SQ_execute_query(tr->sql_connection, "UNLOCK TABLES ", NULL);
  64    if (sql_err) { 
  65         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), "UNLOCK TABLES");
  66         die;
  67     }
  68  return(sql_err);
  69 }
  70 
  71 
  72 /************************************************************
  73 * UD_create_serial()                                        *     
  74 *                                                           *
  75 * Creates a serial record for given transaction             *
  76 *                                                           *
  77 * Important fields of transaction are:                      *
  78 * tr->action        TR_CREATE/TR_UPDATE/TR_DELETE           *
  79 * tr->object_id     should be filled in                     *
  80 * tr->sequence_id   should be set to object updated         *
  81 *                                                           *
  82 * So given object with id=k and seq=n                       *
  83 * Create:  ADD(k,n)                                         *
  84 * Update:  ~S(k,n), ADD(k,n+1)                              *
  85 * Delete:  ~S(k,n), DEL(k,n)                                *
  86 *                                                           *
  87 * Returns:                                                  *
  88 *  current serial number.                                    *
  89 *  -1 in case of an error                                   *
  90 *                                                           *
  91 *************************************************************/
  92 
  93 long UD_create_serial(Transaction_t *tr)
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  94 {
  95 int sql_err;
  96 int operation;
  97 long timestamp;
  98 long sequence_id;
  99    
 100  /* Calculate the object_id - should be max+1 */
 101  /* XXX we cannot use autoincrement with MyISAM tables */
 102  /* XXX because they keep the max inserted id even if  */
 103  /* XXX it was deleted later, thus causing gaps we don't want */
 104     tr->serial_id = SQ_get_max_id(tr->sql_connection, "serial_id", "serials") +1;
 105 
 106   /* if the transaction failed store it in transaction table */
 107   if(tr->succeeded==0){
 108     if(ACT_DELETE(tr->action))operation=OP_DEL; else operation=OP_ADD;
 109     
 110     g_string_sprintf(tr->query, "INSERT serials SET "
 111                    "thread_id=%d, serial_id=%ld, object_id=%ld, sequence_id=0, "
 112                    "atlast=2, "
 113                    "operation=%d ", tr->thread_ins, tr->serial_id, tr->object_id, operation);
 114     
 115     sql_err = SQ_execute_query(tr->sql_connection, tr->query->str, (SQ_result_set_t **)NULL);
 116 
 117     if (sql_err) { 
 118         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), tr->query->str);
 119         die;
 120     }
 121     else {
 122        timestamp=time(NULL);
 123        g_string_sprintf(tr->query, "INSERT failed_transaction SET "
 124                    "thread_id=%d, serial_id=%ld, timestamp=%ld, "
 125                    "object='%s' ", tr->thread_ins, tr->serial_id, timestamp, tr->object_txt);
 126        /* make a record in transaction table */
 127        sql_err = SQ_execute_query(tr->sql_connection, tr->query->str, (SQ_result_set_t **)NULL);
 128        if (sql_err) { 
 129          ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), tr->query->str);
 130          die;
 131        }
 132     }
 133     return(tr->serial_id);
 134   }  
 135 
 136 
 137   /* if the transaction has succeeded */
 138   sequence_id=tr->sequence_id;
 139   /* If this is an update or delete */    
 140   if(!ACT_CREATE(tr->action)) { 
 141     /* Increase the sequence_id so we insert correct ADD serial in case of Update */
 142     sequence_id=tr->sequence_id + 1;
 143     
 144     /* set the atlast field of the latest record for this object to 0 */
 145     /* because it is moved to history */
 146     g_string_sprintf(tr->query, "UPDATE serials SET atlast=0, thread_id=%d "
 147                    "WHERE object_id=%ld "
 148                    "AND sequence_id=%ld ", tr->thread_upd, tr->object_id, sequence_id-1);
 149     
 150     sql_err = SQ_execute_query(tr->sql_connection, tr->query->str, (SQ_result_set_t **)NULL);
 151     if (sql_err) { // we can have empty updates, but not errors
 152         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), tr->query->str);
 153         die;
 154     }
 155   }  
 156   /* XXX below is a code for protocol v2, where updates are atomic */
 157   /* XXX this is fine (and should always be used) for NRTM, since we */
 158   /* XXX store failed transactions and playback stream exactly as it comes */
 159   /* XXX However, for update this may be configurable option */
 160   /* XXX In case v1 protocol both sections (DEL + ADD) should be executed */
 161   
 162   /* get the next serial_id */
 163   /* XXX we cannot use autoincrement with MyISAM tables */
 164   /* XXX because they keep the max inserted id even if  */
 165   /* XXX it was deleted later, thus causing gaps we don't want */
 166   tr->serial_id = SQ_get_max_id(tr->sql_connection, "serial_id", "serials") +1;
 167   
 168   /* if this a DEL */ 
 169   
 170   
 171   if(ACT_DELETE(tr->action)) {   
 172     /* generate DEL serial */
 173         
 174     g_string_sprintf(tr->query, "INSERT serials SET "
 175                    "thread_id=%d, serial_id=%ld, object_id=%ld, "
 176                    "sequence_id=%ld, "
 177                    "atlast=0, "
 178                    "operation=%d ", tr->thread_ins, tr->serial_id, tr->object_id, sequence_id-1, OP_DEL);
 179     
 180     sql_err = SQ_execute_query(tr->sql_connection, tr->query->str, (SQ_result_set_t **)NULL);
 181     if (sql_err) {
 182         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), tr->query->str);
 183         die;
 184     }    
 185     
 186   }
 187   else { /* otherwise this is an ADD */
 188 
 189    /* now insert creation serial */
 190    g_string_sprintf(tr->query, "INSERT serials SET "
 191                   "thread_id=%d, serial_id=%ld, object_id=%ld, "
 192                   "sequence_id=%ld, "
 193                   "atlast=1, "
 194                   "operation=%d ", tr->thread_ins, tr->serial_id, tr->object_id, sequence_id, OP_ADD);
 195     
 196    sql_err = SQ_execute_query(tr->sql_connection, tr->query->str, (SQ_result_set_t **)NULL);
 197    if (sql_err) {
 198         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), tr->query->str);
 199         die;
 200    }    
 201 
 202   }
 203   return(tr->serial_id);
 204 }
 205 /************************************************************
 206 * UD_comrol_serial()                                        *     
 207 *                                                           *
 208 * Commits/Rollbacks a serial record for given transaction   *
 209 * Returns:                                                  *
 210 * 0 in success                                              *
 211 *  -1 in case of an error                                   *
 212 *                                                           *
 213 *************************************************************/
 214 
 215 char *Q_rollback_serial1="DELETE FROM serials WHERE thread_id=%ld ";
 216 char *Q_rollback_serial2="UPDATE serials SET atlast=1, thread_id=0 WHERE thread_id=%ld ";
 217 char *Q_rollback_transaction="DELETE FROM failed_transaction WHERE thread_id=%ld ";
 218 char *Q_commit_serial="UPDATE serials SET thread_id=0 WHERE thread_id=%ld OR thread_id=%ld ";
 219 char *Q_commit_transaction="UPDATE failed_transaction SET thread_id=0 WHERE thread_id=%ld ";
 220 
 221 
 222 
 223 int UD_comrol_serial(Transaction_t *tr, int commit)
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 224 {
 225 int sql_err;
 226 char *Q_transaction;
 227 
 228    /* check if something is left in serials from the crash */
 229    
 230    /* compose the appropriate query depending on operation (commit/rollback) */
 231    if(commit) {
 232            /* commit changes to serials table */
 233            g_string_sprintf(tr->query, Q_commit_serial, tr->thread_ins, tr->thread_upd);
 234            sql_err = SQ_execute_query(tr->sql_connection, tr->query->str, (SQ_result_set_t **)NULL);
 235            if (sql_err) {
 236              ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), tr->query->str);
 237              die;
 238            }
 239            Q_transaction=Q_commit_transaction;
 240    } else {
 241            /* delete new insertions */
 242            g_string_sprintf(tr->query, Q_rollback_serial1, tr->thread_ins);
 243            sql_err = SQ_execute_query(tr->sql_connection, tr->query->str, (SQ_result_set_t **)NULL);
 244            if (sql_err) {
 245              ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), tr->query->str);
 246              die;
 247            }
 248            /* restore modified atlast */ 
 249            g_string_sprintf(tr->query, Q_rollback_serial2, tr->thread_upd);
 250            sql_err = SQ_execute_query(tr->sql_connection, tr->query->str, (SQ_result_set_t **)NULL);
 251            if (sql_err) {
 252              ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), tr->query->str);
 253              die;
 254            } 
 255            Q_transaction=Q_rollback_transaction;
 256    }
 257    
 258     /* clean up transaction  table */
 259     g_string_sprintf(tr->query, Q_transaction, tr->thread_ins);
 260     sql_err = SQ_execute_query(tr->sql_connection, tr->query->str, (SQ_result_set_t **)NULL);
 261     if (sql_err) {
 262         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), tr->query->str);
 263         die;
 264     }
 265  return(0);
 266 } 
 267     
 268 

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