messshm.h Source File

00001 //
00002 // messshm.h
00003 //
00004 // Copyright (C) 1996 Limit Point Systems, Inc.
00005 //
00006 // Author: Curtis Janssen <cljanss@limitpt.com>
00007 // Maintainer: LPS
00008 //
00009 // This file is part of the SC Toolkit.
00010 //
00011 // The SC Toolkit is free software; you can redistribute it and/or modify
00012 // it under the terms of the GNU Library General Public License as published by
00013 // the Free Software Foundation; either version 2, or (at your option)
00014 // any later version.
00015 //
00016 // The SC Toolkit is distributed in the hope that it will be useful,
00017 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00018 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00019 // GNU Library General Public License for more details.
00020 //
00021 // You should have received a copy of the GNU Library General Public License
00022 // along with the SC Toolkit; see the file COPYING.LIB.  If not, write to
00023 // the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
00024 //
00025 // The U.S. Government is granted a limited license as per AL 91-7.
00026 //
00027 
00028 #ifndef _util_group_messshm_h
00029 #define _util_group_messshm_h
00030 
00031 #include <unistd.h>
00032 #include <sys/types.h>
00033 #include <sys/ipc.h>
00034 #include <sys/sem.h>
00035 #include <sys/shm.h>
00036 
00037 #include <util/group/message.h>
00038 
00039 namespace sc {
00040 
00041 #define SHMCOMMBUFSIZE 1500000
00042 
00043 /* Set the maximum number of processors (including the host). */
00044 #define MAXPROCS 17
00045 
00046 
00047 struct commbuf_struct {
00048     int nmsg;
00049     int n_wait_for_change;
00050     int n_sync;
00051     char buf[SHMCOMMBUFSIZE];
00052 };
00053 typedef struct commbuf_struct commbuf_t;
00054 
00055 struct msgbuf_struct {
00056     int type;
00057     int from;
00058     int size;
00059 };
00060 typedef struct msgbuf_struct msgbuf_t;
00061 
00068 class ShmMessageGrp: public intMessageGrp {
00069   protected:
00070     void basic_send(int target, int type, void* data, int nbyte);
00071     void basic_recv(int type, void* data, int nbyte);
00072     int basic_probe(int type);
00073     void initialize(int nprocs);
00074     void initialize();
00075 
00076     // previously static variables
00077     commbuf_t *commbuf[MAXPROCS];
00078     int shmid;
00079     int semid;
00080     int change_semid;
00081     void* sharedmem;
00082     struct sembuf semdec;
00083     struct sembuf seminc;
00084 
00085     // previously static functions for semephore operations
00086     msgbuf_t *NEXT_MESSAGE(msgbuf_t *m);
00087     void get_change(int node);
00088     void put_change(int node);
00089     void wait_for_write(int node);
00090     void release_write(int node);
00091 #ifdef DEBUG
00092     void print_buffer(int node, int me);
00093 #endif
00094   public:
00096     ShmMessageGrp();
00106     ShmMessageGrp(const Ref<KeyVal>&);
00108     ShmMessageGrp(int nprocs);
00109     ~ShmMessageGrp();
00110     void sync();
00111 
00112     Ref<MessageGrp> clone(void);
00113 };
00114 
00115 }
00116      
00117 #endif
00118 
00119 // Local Variables:
00120 // mode: c++
00121 // c-file-style: "CLJ"
00122 // End: