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) 2000,2001                         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 void BEKILLED()
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  36 {
  37 
  38  kill(getpid(), SIGKILL); 
  39 
  40 
  41 }
  42          
  43 /************************************************************
  44 * int UD_lock/unlock_serial()                               *
  45 *                                                           *
  46 * Performs lockind/unlocking of the relevant tables         *
  47 *                                                           *
  48 * Returns:                                                  *
  49 * 0 - success                                               *
  50 * Non-zero if error occured (XXX dies now)                  *
  51 *                                                           *
  52 ************************************************************/
  53 int UD_lock_serial(Transaction_t *tr)
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  54 {
  55 int sql_err;
  56 
  57 /* lock all tables we are going to update and commit */ 
  58 /* this also includes transaction_rec table, as we update the status */
  59    sql_err=SQ_execute_query(tr->sql_connection, "LOCK TABLES serials WRITE, failed_transaction WRITE, transaction_rec WRITE ", NULL);
  60    if (sql_err) { 
  61         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), "LOCK TABLES serials WRITE, failed_transaction WRITE, transaction_rec WRITE ");
  62         die;
  63     }
  64  return(sql_err);
  65 }
  66 
  67 int UD_unlock_serial(Transaction_t *tr)
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  68 {
  69 int sql_err;
  70         
  71    sql_err=SQ_execute_query(tr->sql_connection, "UNLOCK TABLES ", NULL);
  72    if (sql_err) { 
  73         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), "UNLOCK TABLES");
  74         die;
  75     }
  76  return(sql_err);
  77 }
  78 
  79 
  80 /************************************************************
  81 * UD_create_serial()                                        *     
  82 *                                                           *
  83 * Creates a serial record for given transaction             *
  84 *                                                           *
  85 * Important fields of transaction are:                      *
  86 * tr->action        TR_CREATE/TR_UPDATE/TR_DELETE           *
  87 * tr->object_id     should be filled in                     *
  88 * tr->sequence_id   should be set to object updated         *
  89 *                                                           *
  90 * So given object with id=k and seq=n                       *
  91 * Create:  ADD(k,n)                                         *
  92 * Update:  ~S(k,n), ADD(k,n+1)                              *
  93 * Delete:  ~S(k,n), DEL(k,n)                                *
  94 *                                                           *
  95 * Returns:                                                  *
  96 *  current serial number.                                    *
  97 *  -1 in case of an error                                   *
  98 *                                                           *
  99 *************************************************************/
 100 
 101 long UD_create_serial(Transaction_t *tr)
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 102 {
 103 GString *query;
 104 //long current_serial=0;
 105 int sql_err;
 106 int operation;
 107 long timestamp;
 108 long sequence_id;
 109    
 110    if ((query = g_string_sized_new(STR_XL)) == NULL){ 
 111       tr->succeeded=0;
 112       tr->error |= ERROR_U_MEM;
 113       ER_perror(FAC_UD, UD_MEM, "cannot allocate gstring\n");
 114       die;
 115    }
 116    
 117  /* Calculate the object_id - should be max+1 */
 118  /* XXX we cannot use autoincrement with MyISAM tables */
 119  /* XXX because they keep the max inserted id even if  */
 120  /* XXX it was deleted later, thus causing gaps we don't want */
 121     tr->serial_id = SQ_get_max_id(tr->sql_connection, "serial_id", "serials") +1;
 122 
 123   /* if the transaction failed store it in transaction table */
 124   if(tr->succeeded==0){
 125     if(ACT_DELETE(tr->action))operation=OP_DEL; else operation=OP_ADD;
 126     
 127     g_string_sprintf(query, "INSERT serials SET "
 128                    "thread_id=%d, serial_id=%ld, object_id=%ld, sequence_id=0, "
 129                    "atlast=2, "
 130                    "operation=%d ", tr->thread_ins, tr->serial_id, tr->object_id, operation);
 131     
 132     sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
 133 
 134     if (sql_err) { 
 135         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
 136 //      current_serial=-1;
 137         die;
 138     }
 139     else {
 140        timestamp=time(NULL);
 141        g_string_sprintf(query, "INSERT failed_transaction SET "
 142                    "thread_id=%d, serial_id=%ld, timestamp=%ld, "
 143                    "object='%s' ", tr->thread_ins, tr->serial_id, timestamp, tr->object->object->str);
 144        /* make a record in transaction table */
 145        sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
 146        if (sql_err) { 
 147          ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
 148          die;
 149        }
 150     }
 151     g_string_free(query, TRUE);   
 152     return(tr->serial_id);
 153   }  
 154 
 155 
 156   /* if the transaction has succeeded */
 157   sequence_id=tr->sequence_id;
 158   /* If this is an update or delete */    
 159   if(!ACT_CREATE(tr->action)) { 
 160     /* Increase the sequence_id so we insert correct ADD serial in case of Update */
 161     sequence_id=tr->sequence_id + 1;
 162     
 163     /* set the atlast field of the latest record for this object to 0 */
 164     /* because it is moved to history */
 165     g_string_sprintf(query, "UPDATE serials SET atlast=0, thread_id=%d "
 166                    "WHERE object_id=%ld "
 167                    "AND sequence_id=%ld ", tr->thread_upd, tr->object_id, sequence_id-1);
 168     
 169     sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
 170     if (sql_err) { // we can have empty updates, but not errors
 171         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
 172         die;
 173     }
 174   }  
 175   /* XXX below is a code for protocol v2, where updates are atomic */
 176   /* XXX this is fine (and should always be used) for NRTM, since we */
 177   /* XXX store failed transactions and playback stream exactly as it comes */
 178   /* XXX However, for update this may be configurable option */
 179   /* XXX In case v1 protocol both sections (DEL + ADD) should be executed */
 180   
 181   /* get the next serial_id */
 182   /* XXX we cannot use autoincrement with MyISAM tables */
 183   /* XXX because they keep the max inserted id even if  */
 184   /* XXX it was deleted later, thus causing gaps we don't want */
 185   tr->serial_id = SQ_get_max_id(tr->sql_connection, "serial_id", "serials") +1;
 186   
 187   /* if this a DEL */ 
 188   
 189   
 190   if(ACT_DELETE(tr->action)) {   
 191     /* generate DEL serial */
 192         
 193     g_string_sprintf(query, "INSERT serials SET "
 194                    "thread_id=%d, serial_id=%ld, object_id=%ld, "
 195                    "sequence_id=%ld, "
 196                    "atlast=0, "
 197                    "operation=%d ", tr->thread_ins, tr->serial_id, tr->object_id, sequence_id-1, OP_DEL);
 198     
 199     sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
 200     if (sql_err) {
 201         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
 202         die;
 203     }    
 204     
 205   }
 206   else { /* otherwise this is an ADD */
 207 
 208    /* now insert creation serial */
 209    g_string_sprintf(query, "INSERT serials SET "
 210                   "thread_id=%d, serial_id=%ld, object_id=%ld, "
 211                   "sequence_id=%ld, "
 212                   "atlast=1, "
 213                   "operation=%d ", tr->thread_ins, tr->serial_id, tr->object_id, sequence_id, OP_ADD);
 214     
 215    sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
 216    if (sql_err) {
 217         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
 218         die;
 219    }    
 220 
 221   }
 222   g_string_free(query, TRUE);        
 223 return(tr->serial_id);
 224 }
 225 /************************************************************
 226 * UD_comrol_serial()                                        *     
 227 *                                                           *
 228 * Commits/Rollbacks a serial record for given transaction   *
 229 * Returns:                                                  *
 230 * 0 in success                                              *
 231 *  -1 in case of an error                                   *
 232 *                                                           *
 233 *************************************************************/
 234 
 235 char *Q_rollback_serial1="DELETE FROM serials WHERE thread_id=%ld ";
 236 char *Q_rollback_serial2="UPDATE serials SET atlast=1, thread_id=0 WHERE thread_id=%ld ";
 237 char *Q_rollback_transaction="DELETE FROM failed_transaction WHERE thread_id=%ld ";
 238 char *Q_commit_serial="UPDATE serials SET thread_id=0 WHERE thread_id=%ld OR thread_id=%ld ";
 239 char *Q_commit_transaction="UPDATE failed_transaction SET thread_id=0 WHERE thread_id=%ld ";
 240 
 241 
 242 
 243 int UD_comrol_serial(Transaction_t *tr, int commit)
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 244 {
 245 GString *query;
 246 int sql_err;
 247 char *Q_transaction;
 248 
 249    /* check if something is left in serials from the crash */
 250    
 251    if ((query = g_string_sized_new(STR_XL)) == NULL){ 
 252       ER_perror(FAC_UD, UD_MEM, "cannot allocate gstring\n"); 
 253       tr->succeeded=0;
 254       tr->error |= ERROR_U_MEM;
 255       return(ERROR_U_MEM); 
 256    }
 257    
 258    /* compose the appropriate query depending on operation (commit/rollback) */
 259    if(commit) {
 260            /* commit changes to serials table */
 261            g_string_sprintf(query, Q_commit_serial, tr->thread_ins, tr->thread_upd);
 262            sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
 263            if (sql_err) {
 264              ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
 265              die;
 266            }
 267            Q_transaction=Q_commit_transaction;
 268    } else {
 269            /* delete new insertions */
 270            g_string_sprintf(query, Q_rollback_serial1, tr->thread_ins);
 271            sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
 272            if (sql_err) {
 273              ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
 274              die;
 275            }
 276            /* restore modified atlast */ 
 277            g_string_sprintf(query, Q_rollback_serial2, tr->thread_upd);
 278            sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
 279            if (sql_err) {
 280              ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
 281              die;
 282            } 
 283            Q_transaction=Q_rollback_transaction;
 284    }
 285    
 286     /* clean up transaction  table */
 287     g_string_sprintf(query, Q_transaction, tr->thread_ins);
 288     sql_err = SQ_execute_query(tr->sql_connection, query->str, (SQ_result_set_t **)NULL);
 289     if (sql_err) {
 290         ER_perror(FAC_UD, UD_SQL, "%s[%s]\n", SQ_error(tr->sql_connection), query->str);
 291         die;
 292     }
 293  g_string_free(query, TRUE);        
 294  return(0);
 295 } 
 296     
 297 

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