src/DiskIO/DiskIOModule.cc

   1 /*
   2  *
   3  * DEBUG: section 92    Storage File System
   4  * AUTHOR: Robert Collins
   5  *
   6  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   7  * ----------------------------------------------------------
   8  *
   9  *  Squid is the result of efforts by numerous individuals from
  10  *  the Internet community; see the CONTRIBUTORS file for full
  11  *  details.   Many organizations have provided support for Squid's
  12  *  development; see the SPONSORS file for full details.  Squid is
  13  *  Copyrighted (C) 2001 by the Regents of the University of
  14  *  California; see the COPYRIGHT file for full details.  Squid
  15  *  incorporates software developed and/or copyrighted by other
  16  *  sources; see the CREDITS file for full details.
  17  *
  18  *  This program is free software; you can redistribute it and/or modify
  19  *  it under the terms of the GNU General Public License as published by
  20  *  the Free Software Foundation; either version 2 of the License, or
  21  *  (at your option) any later version.
  22  *
  23  *  This program is distributed in the hope that it will be useful,
  24  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  25  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26  *  GNU General Public License for more details.
  27  *
  28  *  You should have received a copy of the GNU General Public License
  29  *  along with this program; if not, write to the Free Software
  30  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  31  *
  32  * Copyright (c) 2003, Robert Collins <robertc@squid-cache.org>
  33  */
  34
  35 #include "squid.h"
  36 #include "DiskIOModule.h"
  37
  38 Vector<DiskIOModule*> *DiskIOModule::_Modules = NULL;
  39
  40 //DiskIOModule() : initialised (false) {}
  41
  42 DiskIOModule::DiskIOModule()
  43 {
  44     /** We cannot call ModuleAdd(*this)
  45      * here as the virtual methods are not yet available.
  46      * We leave that to PokeAllModules() later.
  47      */
  48 }
  49
  50 void
  51 DiskIOModule::SetupAllModules()
  52 {
  53     DiskIOModule::PokeAllModules();
  54
  55     for (iterator i = GetModules().begin(); i != GetModules().end(); ++i)
  56         /* Call the FS to set up capabilities and initialize the FS driver */
  57         (*i)->init();
  58 }
  59
  60 void
  61 DiskIOModule::ModuleAdd(DiskIOModule &instance)
  62 {
  63     iterator i = GetModules().begin();
  64
  65     while (i != GetModules().end()) {
  66         assert(strcmp((*i)->type(), instance.type()) != 0);
  67         ++i;
  68     }
  69
  70     GetModules().push_back (&instance);
  71 }
  72
  73 Vector<DiskIOModule *> const &
  74 DiskIOModule::Modules()
  75 {
  76     return GetModules();
  77 }
  78
  79 Vector<DiskIOModule*> &
  80 DiskIOModule::GetModules()
  81 {
  82     if (!_Modules)
  83         _Modules = new Vector<DiskIOModule *>;
  84
  85     return *_Modules;
  86 }
  87
  88 /**
  89  * Called when a graceful shutdown is to occur
  90  * of each fs module.
  91  */
  92 void
  93 DiskIOModule::FreeAllModules()
  94 {
  95     while (!GetModules().empty()) {
  96         DiskIOModule *fs = GetModules().back();
  97         GetModules().pop_back();
  98         fs->gracefulShutdown();
  99     }
 100 }
 101
 102 DiskIOModule *
 103 DiskIOModule::Find(char const *type)
 104 {
 105     for (iterator i = GetModules().begin(); i != GetModules().end(); ++i)
 106         if (strcasecmp(type, (*i)->type()) == 0)
 107             return *i;
 108
 109     return NULL;
 110 }
 111
 112 DiskIOModule *
 113 DiskIOModule::FindDefault()
 114 {
 115     /** Best IO options are in order: */
 116     DiskIOModule * result;
 117     result = Find("DiskThreads");
 118     if (NULL == result)
 119         result = Find("DiskDaemon");
 120     if (NULL == result)
 121         result = Find("AIO");
 122     if (NULL == result)
 123         result = Find("Blocking");
 124     return result;
 125 }