release/src/router/mysql/storage/ndb/src/common/transporter/SHM_Transporter.unix.cpp

   1 /* Copyright (c) 2003-2005 MySQL AB
   2
   3    This program is free software; you can redistribute it and/or modify
   4    it under the terms of the GNU General Public License as published by
   5    the Free Software Foundation; version 2 of the License.
   6
   7    This program is distributed in the hope that it will be useful,
   8    but WITHOUT ANY WARRANTY; without even the implied warranty of
   9    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10    GNU General Public License for more details.
  11
  12    You should have received a copy of the GNU General Public License
  13    along with this program; if not, write to the Free Software
  14    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA */
  15
  16
  17 #include <ndb_global.h>
  18
  19 #include "SHM_Transporter.hpp"
  20 #include "TransporterInternalDefinitions.hpp"
  21 #include <TransporterCallback.hpp>
  22 #include <NdbSleep.h>
  23 #include <NdbOut.hpp>
  24
  25 #include <sys/ipc.h>
  26 #include <sys/shm.h>
  27
  28 void SHM_Transporter::make_error_info(char info[], int sz)
  29 {
  30   snprintf(info,sz,"Shm key=%d sz=%d id=%d",
  31            shmKey, shmSize, shmId);
  32 }
  33
  34 bool
  35 SHM_Transporter::ndb_shm_create()
  36 {
  37   shmId = shmget(shmKey, shmSize, IPC_CREAT | 960);
  38   if(shmId == -1) {
  39     perror("shmget: ");
  40     return false;
  41   }
  42   return true;
  43 }
  44
  45 bool
  46 SHM_Transporter::ndb_shm_get()
  47 {
  48   shmId = shmget(shmKey, shmSize, 0);
  49   if(shmId == -1) {
  50     perror("shmget: ");
  51     return false;
  52   }
  53   return true;
  54 }
  55
  56 bool
  57 SHM_Transporter::ndb_shm_attach()
  58 {
  59   shmBuf = (char *)shmat(shmId, 0, 0);
  60   if(shmBuf == 0) {
  61     perror("shmat: ");
  62     return false;
  63   }
  64   return true;
  65 }
  66
  67 bool
  68 SHM_Transporter::checkConnected(){
  69   struct shmid_ds info;
  70   const int res = shmctl(shmId, IPC_STAT, &info);
  71   if(res == -1){
  72     char buf[128];
  73     int r= snprintf(buf, sizeof(buf),
  74                     "shmctl(%d, IPC_STAT) errno: %d(%s). ", shmId,
  75                     errno, strerror(errno));
  76     make_error_info(buf+r, sizeof(buf)-r);
  77     DBUG_PRINT("error",(buf));
  78     switch (errno)
  79     {
  80     case EACCES:
  81       report_error(TE_SHM_IPC_PERMANENT, buf);
  82       break;
  83     default:
  84       report_error(TE_SHM_IPC_STAT, buf);
  85       break;
  86     }
  87     return false;
  88   }
  89
  90   if(info.shm_nattch != 2){
  91     char buf[128];
  92     make_error_info(buf, sizeof(buf));
  93     report_error(TE_SHM_DISCONNECT);
  94     DBUG_PRINT("error", ("Already connected to node %d",
  95                 remoteNodeId));
  96     return false;
  97   }
  98   return true;
  99 }
 100
 101 void
 102 SHM_Transporter::disconnectImpl(){
 103   if(_attached){
 104     const int res = shmdt(shmBuf);
 105     if(res == -1){
 106       perror("shmdelete: ");
 107       return;
 108     }
 109     _attached = false;
 110     if(!isServer && _shmSegCreated)
 111       _shmSegCreated = false;
 112   }
 113
 114   if(isServer && _shmSegCreated){
 115     const int res = shmctl(shmId, IPC_RMID, 0);
 116     if(res == -1){
 117       char buf[64];
 118       make_error_info(buf, sizeof(buf));
 119       report_error(TE_SHM_UNABLE_TO_REMOVE_SEGMENT);
 120       return;
 121     }
 122     _shmSegCreated = false;
 123   }
 124   setupBuffersDone=false;
 125 }