## modules/ud/ud_serial.c

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## FUNCTIONS

This source file includes following functions.

1. BEKILLED
2. UD_lock_serial
3. UD_unlock_serial
4. UD_create_serial
5. 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                              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 #include "ud.h"
      33 #include "ud_int.h"
      34 #include "ud_tr.h"
      35
      36 void BEKILLED()
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      37 {
      38
      39  kill(getpid(), SIGKILL);
      40
      41
      42 }
      43
      44 /************************************************************
      45 * int UD_lock/unlock_serial()                               *
      46 *                                                           *
      47 * Performs lockind/unlocking of the relevant tables         *
      48 *                                                           *
      49 * Returns:                                                  *
      50 * 0 - success                                               *
      51 * Non-zero if error occured (XXX dies now)                  *
      52 *                                                           *
      53 ************************************************************/
      54 int UD_lock_serial(Transaction_t *tr)
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      55 {
      56 int sql_err;
      57
      58 /* lock all tables we are going to update and commit */
      59 /* this also includes transaction_rec table, as we update the status */
      60    sql_err=SQ_execute_query(tr->sql_connection, "LOCK TABLES serials WRITE, failed_transaction WRITE, transaction_rec WRITE ", NULL);
      61    if (sql_err) {
      62         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), "LOCK TABLES serials WRITE, failed_transaction WRITE, transaction_rec WRITE ");
      63         die;
      64     }
      65  return(sql_err);
      66 }
      67
      68 int UD_unlock_serial(Transaction_t *tr)
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      69 {
      70 int sql_err;
      71
      72    sql_err=SQ_execute_query(tr->sql_connection, "UNLOCK TABLES ", NULL);
      73    if (sql_err) {
      74         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), "UNLOCK TABLES");
      75         die;
      76     }
      77  return(sql_err);
      78 }
      79
      80
      81 /************************************************************
      82 * UD_create_serial()                                        *
      83 *                                                           *
      84 * Creates a serial record for given transaction             *
      85 *                                                           *
      86 * Important fields of transaction are:                      *
      87 * tr->action        TR_CREATE/TR_UPDATE/TR_DELETE           *
      88 * tr->object_id     should be filled in                     *
      89 * tr->sequence_id   should be set to object updated         *
      90 *                                                           *
      91 * So given object with id=k and seq=n                       *
      92 * Create:  ADD(k,n)                                         *
      93 * Update:  ~S(k,n), ADD(k,n+1)                              *
      94 * Delete:  ~S(k,n), DEL(k,n)                                *
      95 *                                                           *
      96 * Returns:                                                  *
      97 *  current serial number.                                    *
      98 *  -1 in case of an error                                   *
      99 *                                                           *
     100 *************************************************************/
     101
     102 long UD_create_serial(Transaction_t *tr)
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     103 {
     104 GString *query;
     105 //long current_serial=0;
     106 int sql_err;
     107 int operation;
     108 long timestamp;
     109 long sequence_id;
     110
     111    if ((query = g_string_sized_new(STR_XL)) == NULL){
     112       tr->succeeded=0;
     113       tr->error |= ERROR_U_MEM;
     114       ER_perror(FAC_UD, UD_MEM, "cannot allocate gstring\n");
     115       die;
     116    }
     117
     118  /* Calculate the object_id - should be max+1 */
     119  /* XXX we cannot use autoincrement with MyISAM tables */
     120  /* XXX because they keep the max inserted id even if  */
     121  /* XXX it was deleted later, thus causing gaps we don't want */
     122     tr->serial_id = SQ_get_max_id(tr->sql_connection, "serial_id", "serials") +1;
     123
     124   /* if the transaction failed store it in transaction table */
     125   if(tr->succeeded==0){
     126     if(ACT_DELETE(tr->action))operation=OP_DEL; else operation=OP_ADD;
     127
     128     g_string_sprintf(query, "INSERT serials SET "
     129                    "thread_id=%d, serial_id=%ld, object_id=%ld, sequence_id=0, "
     130                    "atlast=2, "
     131                    "operation=%d ", tr->thread_ins, tr->serial_id, tr->object_id, operation);
     132
     133     sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
     134
     135     if (sql_err) {
     136         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
     137 //      current_serial=-1;
     138         die;
     139     }
     140     else {
     141        timestamp=time(NULL);
     142        g_string_sprintf(query, "INSERT failed_transaction SET "
     143                    "thread_id=%d, serial_id=%ld, timestamp=%ld, "
     144                    "object='%s' ", tr->thread_ins, tr->serial_id, timestamp, tr->object->object->str);
     145        /* make a record in transaction table */
     146        sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
     147        if (sql_err) {
     148          ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
     149          die;
     150        }
     151     }
     152     g_string_free(query, TRUE);
     153     return(tr->serial_id);
     154   }
     155
     156
     157   /* if the transaction has succeeded */
     158   sequence_id=tr->sequence_id;
     159   /* If this is an update or delete */
     160   if(!ACT_CREATE(tr->action)) {
     161     /* Increase the sequence_id so we insert correct ADD serial in case of Update */
     162     sequence_id=tr->sequence_id + 1;
     163
     164     /* set the atlast field of the latest record for this object to 0 */
     165     /* because it is moved to history */
     166     g_string_sprintf(query, "UPDATE serials SET atlast=0, thread_id=%d "
     167                    "WHERE object_id=%ld "
     168                    "AND sequence_id=%ld ", tr->thread_upd, tr->object_id, sequence_id-1);
     169
     170     sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
     171     if (sql_err) { // we can have empty updates, but not errors
     172         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
     173         die;
     174     }
     175   }
     176   /* XXX below is a code for protocol v2, where updates are atomic */
     177   /* XXX this is fine (and should always be used) for NRTM, since we */
     178   /* XXX store failed transactions and playback stream exactly as it comes */
     179   /* XXX However, for update this may be configurable option */
     180   /* XXX In case v1 protocol both sections (DEL + ADD) should be executed */
     181
     182   /* get the next serial_id */
     183   /* XXX we cannot use autoincrement with MyISAM tables */
     184   /* XXX because they keep the max inserted id even if  */
     185   /* XXX it was deleted later, thus causing gaps we don't want */
     186   tr->serial_id = SQ_get_max_id(tr->sql_connection, "serial_id", "serials") +1;
     187
     188   /* if this a DEL */
     189
     190
     191   if(ACT_DELETE(tr->action)) {
     192     /* generate DEL serial */
     193
     194     g_string_sprintf(query, "INSERT serials SET "
     195                    "thread_id=%d, serial_id=%ld, object_id=%ld, "
     196                    "sequence_id=%ld, "
     197                    "atlast=0, "
     198                    "operation=%d ", tr->thread_ins, tr->serial_id, tr->object_id, sequence_id-1, OP_DEL);
     199
     200     sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
     201     if (sql_err) {
     202         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
     203         die;
     204     }
     205
     206   }
     207   else { /* otherwise this is an ADD */
     208
     209    /* now insert creation serial */
     210    g_string_sprintf(query, "INSERT serials SET "
     211                   "thread_id=%d, serial_id=%ld, object_id=%ld, "
     212                   "sequence_id=%ld, "
     213                   "atlast=1, "
     214                   "operation=%d ", tr->thread_ins, tr->serial_id, tr->object_id, sequence_id, OP_ADD);
     215
     216    sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
     217    if (sql_err) {
     218         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
     219         die;
     220    }
     221
     222   }
     223   g_string_free(query, TRUE);
     224 return(tr->serial_id);
     225 }
     226 /************************************************************
     227 * UD_comrol_serial()                                        *
     228 *                                                           *
     229 * Commits/Rollbacks a serial record for given transaction   *
     230 * Returns:                                                  *
     231 * 0 in success                                              *
     232 *  -1 in case of an error                                   *
     233 *                                                           *
     234 *************************************************************/
     235
     236 char *Q_rollback_serial1="DELETE FROM serials WHERE thread_id=%ld ";
     237 char *Q_rollback_serial2="UPDATE serials SET atlast=1, thread_id=0 WHERE thread_id=%ld ";
     238 char *Q_rollback_transaction="DELETE FROM failed_transaction WHERE thread_id=%ld ";
     239 char *Q_commit_serial="UPDATE serials SET thread_id=0 WHERE thread_id=%ld OR thread_id=%ld ";
     240 char *Q_commit_transaction="UPDATE failed_transaction SET thread_id=0 WHERE thread_id=%ld ";
     241
     242
     243
     244 int UD_comrol_serial(Transaction_t *tr, int commit)
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     245 {
     246 GString *query;
     247 int sql_err;
     248 char *Q_transaction;
     249
     250    /* check if something is left in serials from the crash */
     251
     252    if ((query = g_string_sized_new(STR_XL)) == NULL){
     253       ER_perror(FAC_UD, UD_MEM, "cannot allocate gstring\n");
     254       tr->succeeded=0;
     255       tr->error |= ERROR_U_MEM;
     256       return(ERROR_U_MEM);
     257    }
     258
     259    /* compose the appropriate query depending on operation (commit/rollback) */
     260    if(commit) {
     261            /* commit changes to serials table */
     262            g_string_sprintf(query, Q_commit_serial, tr->thread_ins, tr->thread_upd);
     263            sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
     264            if (sql_err) {
     265              ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
     266              die;
     267            }
     268            Q_transaction=Q_commit_transaction;
     269    } else {
     270            /* delete new insertions */
     271            g_string_sprintf(query, Q_rollback_serial1, tr->thread_ins);
     272            sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
     273            if (sql_err) {
     274              ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
     275              die;
     276            }
     277            /* restore modified atlast */
     278            g_string_sprintf(query, Q_rollback_serial2, tr->thread_upd);
     279            sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
     280            if (sql_err) {
     281              ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
     282              die;
     283            }
     284            Q_transaction=Q_rollback_transaction;
     285    }
     286
     287     /* clean up transaction  table */
     288     g_string_sprintf(query, Q_transaction, tr->thread_ins);
     289     sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
     290     if (sql_err) {
     291         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
     292         die;
     293     }
     294  g_string_free(query, TRUE);
     295  return(0);
     296 }
     297
     298

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