git.sur5r.net Git - openldap/blob - servers/slapd/back-ldbm/nextid.c

   1 /* nextid.c - keep track of the next id to be given out */
   2 /* $OpenLDAP$ */
   3 /*
   4  * Copyright 1998-2000 The OpenLDAP Foundation, All Rights Reserved.
   5  * COPYING RESTRICTIONS APPLY, see COPYRIGHT file
   6  */
   7
   8 #include "portable.h"
   9
  10 #include <stdio.h>
  11
  12 #include <ac/string.h>
  13 #include <ac/socket.h>
  14
  15 #ifdef HAVE_SYS_PARAM_H
  16 #include <sys/param.h>
  17 #endif
  18
  19 #include "slap.h"
  20 #include "back-ldbm.h"
  21
  22 static int
  23 next_id_read( Backend *be, ID *idp )
  24 {
  25         Datum key, data;
  26         DBCache *db;
  27
  28         *idp = NOID;
  29
  30         if ( (db = ldbm_cache_open( be, "nextid", LDBM_SUFFIX, LDBM_WRCREAT ))
  31             == NULL ) {
  32 #ifdef NEW_LOGGING
  33                 LDAP_LOG(( "backend", LDAP_LEVEL_CRIT,
  34                            "next_id_read: could not open/create nextid%s\n", LDBM_SUFFIX ));
  35 #else
  36                 Debug( LDAP_DEBUG_ANY, "Could not open/create nextid" LDBM_SUFFIX "\n",
  37                         0, 0, 0 );
  38 #endif
  39
  40                 return( -1 );
  41         }
  42
  43         ldbm_datum_init( key );
  44         key.dptr = (char *) idp;
  45         key.dsize = sizeof(ID);
  46
  47         data = ldbm_cache_fetch( db, key );
  48
  49         if( data.dptr != NULL ) {
  50                 AC_MEMCPY( idp, data.dptr, sizeof( ID ) );
  51                 ldbm_datum_free( db->dbc_db, data );
  52
  53         } else {
  54                 *idp = 1;
  55         }
  56
  57         ldbm_cache_close( be, db );
  58         return( 0 );
  59 }
  60
  61 int
  62 next_id_write( Backend *be, ID id )
  63 {
  64         Datum key, data;
  65         DBCache *db;
  66         ID noid = NOID;
  67         int flags, rc = 0;
  68
  69         if ( (db = ldbm_cache_open( be, "nextid", LDBM_SUFFIX, LDBM_WRCREAT ))
  70             == NULL ) {
  71 #ifdef NEW_LOGGING
  72                 LDAP_LOG(( "backend", LDAP_LEVEL_CRIT,
  73                            "next_id_write: Could not open/create nextid%s\n", LDBM_SUFFIX ));
  74 #else
  75                 Debug( LDAP_DEBUG_ANY, "Could not open/create nextid" LDBM_SUFFIX "\n",
  76                     0, 0, 0 );
  77 #endif
  78
  79                 return( -1 );
  80         }
  81
  82         ldbm_datum_init( key );
  83         ldbm_datum_init( data );
  84
  85         key.dptr = (char *) &noid;
  86         key.dsize = sizeof(ID);
  87
  88         data.dptr = (char *) &id;
  89         data.dsize = sizeof(ID);
  90
  91         flags = LDBM_REPLACE;
  92         if ( ldbm_cache_store( db, key, data, flags ) != 0 ) {
  93                 rc = -1;
  94         }
  95
  96         ldbm_cache_close( be, db );
  97         return( rc );
  98 }
  99
 100 int
 101 next_id_get( Backend *be, ID *idp )
 102 {
 103         struct ldbminfo *li = (struct ldbminfo *) be->be_private;
 104         int rc = 0;
 105
 106         *idp = NOID;
 107
 108         ldap_pvt_thread_mutex_lock( &li->li_nextid_mutex );
 109
 110         if ( li->li_nextid == NOID ) {
 111                 if ( ( rc = next_id_read( be, idp ) ) ) {
 112                         ldap_pvt_thread_mutex_unlock( &li->li_nextid_mutex );
 113                         return( rc );
 114                 }
 115                 li->li_nextid = *idp;
 116         }
 117
 118         *idp = li->li_nextid;
 119
 120         ldap_pvt_thread_mutex_unlock( &li->li_nextid_mutex );
 121         return( rc );
 122 }
 123
 124 int
 125 next_id( Backend *be, ID *idp )
 126 {
 127         struct ldbminfo *li = (struct ldbminfo *) be->be_private;
 128         int rc = 0;
 129
 130         ldap_pvt_thread_mutex_lock( &li->li_nextid_mutex );
 131
 132         if ( li->li_nextid == NOID ) {
 133                 if ( ( rc = next_id_read( be, idp ) ) ) {
 134                         ldap_pvt_thread_mutex_unlock( &li->li_nextid_mutex );
 135                         return( rc );
 136                 }
 137                 li->li_nextid = *idp;
 138         }
 139
 140         *idp = li->li_nextid++;
 141         if ( next_id_write( be, li->li_nextid ) ) {
 142                 rc = -1;
 143         }
 144
 145         ldap_pvt_thread_mutex_unlock( &li->li_nextid_mutex );
 146         return( rc );
 147 }