conflict.cxx

eCos1.31版

//{{{  Banner                           

//============================================================================
//
//      conflict.cxx
//
//      The CdlConflict class
//
//============================================================================
//####COPYRIGHTBEGIN####
//                                                                          
// ----------------------------------------------------------------------------
// Copyright (C) 1999, 2000 Red Hat, Inc.
//
// This file is part of the eCos host tools.
//
// This program is free software; you can redistribute it and/or modify it 
// under the terms of the GNU General Public License as published by the Free 
// Software Foundation; either version 2 of the License, or (at your option) 
// any later version.
// 
// This program is distributed in the hope that it will be useful, but WITHOUT 
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for 
// more details.
// 
// You should have received a copy of the GNU General Public License along with
// this program; if not, write to the Free Software Foundation, Inc., 
// 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
//
// ----------------------------------------------------------------------------
//                                                                          
//####COPYRIGHTEND####
//============================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):   bartv
// Contact(s):  bartv
// Date:        1999/01/28
// Version:     0.02
//
//####DESCRIPTIONEND####
//============================================================================

//}}}
//{{{  #include's                       

// ----------------------------------------------------------------------------
#include "cdlconfig.h"

// Get the infrastructure types, assertions, tracing and similar
// facilities.
#include <cyg/infra/cyg_ass.h>
#include <cyg/infra/cyg_trac.h>

// <cdlcore.hxx> defines everything implemented in this module.
// It implicitly supplies <string>, <vector> and <map> because
// the class definitions rely on these headers. It also brings
// in <tcl.h>
#include <cdlcore.hxx>

//}}}

//{{{  Statics                          

// ----------------------------------------------------------------------------
CYGDBG_DEFINE_MEMLEAK_COUNTER(CdlConflictBody);
CYGDBG_DEFINE_MEMLEAK_COUNTER(CdlConflict_UnresolvedBody);
CYGDBG_DEFINE_MEMLEAK_COUNTER(CdlConflict_IllegalValueBody);
CYGDBG_DEFINE_MEMLEAK_COUNTER(CdlConflict_EvalExceptionBody);
CYGDBG_DEFINE_MEMLEAK_COUNTER(CdlConflict_RequiresBody);
CYGDBG_DEFINE_MEMLEAK_COUNTER(CdlConflict_DataBody);

//}}}
//{{{  CdlConflict                      

//{{{  Creation and destruction                 

// ----------------------------------------------------------------------------
// The basic conflicts. Conflicts are created in the context of a transaction.
// If the transaction gets committed then they are transferred to a toplevel.
// If the transaction gets cancelled then they just disappear.
//
// A conflict that is only part of a transaction may go away as that
// transaction proceeds, in which case it can be deleted immediately.
// A conflict that is already part of the toplevel cannot be
// destroyed, instead it gets marked in the transaction object. Only
// when the transaction is committed does the object get deleted.
// In addition within the context of a transaction old conflicts
// may hang around for a while.
//

CdlConflictBody::CdlConflictBody(CdlTransaction trans_arg, CdlNode node_arg, CdlProperty property_arg, bool structural_arg)
{
    CYG_REPORT_FUNCNAME("CdlConflict:: constructor");
    CYG_REPORT_FUNCARG4XV(this, trans_arg, node_arg, property_arg);
    CYG_PRECONDITION_CLASSC(trans_arg);
    CYG_PRECONDITION_CLASSC(node_arg);
    CYG_PRECONDITION_CLASSC(property_arg);

    node        = node_arg;
    property    = property_arg;
    transaction = trans_arg;
    structural  = structural_arg;
    no_solution = false;
    // The vectors take care of themselves
    enabled     = true;
    reason      = "";

    transaction->dirty = true;
    if (structural_arg) {
        transaction->new_structural_conflicts.push_back(this);
    } else {
        transaction->new_conflicts.push_back(this);
    }
    
    cdlconflictbody_cookie      = CdlConflictBody_Magic;
    CYGDBG_MEMLEAK_CONSTRUCTOR();

    CYG_POSTCONDITION_THISC();
    CYG_REPORT_RETURN();
}


// ----------------------------------------------------------------------------
// The destructor can get invoked during a transaction commit, in the
// case of a global conflict, or from inside clear() for a per-transaction
// conflict. In all cases the calling code is responsible for removing
// the conflict from any STL containers.

CdlConflictBody::~CdlConflictBody()
{
    CYG_REPORT_FUNCNAME("CdlConflict:: destructor");
    CYG_REPORT_FUNCARG1XV(this);
    CYG_PRECONDITION_THISC();

    cdlconflictbody_cookie      = CdlConflictBody_Invalid;
    reason                      = "";
    enabled                     = false;
    no_solution                 = false;
    solution.clear();
    solution_references.clear();
    structural                  = false;
    transaction                 = 0;
    property                    = 0;
    node                        = 0;
    CYGDBG_MEMLEAK_DESTRUCTOR();
    
    CYG_REPORT_RETURN();
}

//}}}
//{{{  Solution support                         

// ----------------------------------------------------------------------------
bool
CdlConflictBody::has_known_solution() const
{
    CYG_REPORT_FUNCNAMETYPE("CdlConflict::has_solution", "result %d");
    CYG_REPORT_FUNCARG1XV(this);
    CYG_PRECONDITION_THISC();

    bool result = (0 != solution.size());
    
    CYG_REPORT_RETVAL(result);
    return result;
}

bool
CdlConflictBody::has_no_solution() const
{
    CYG_REPORT_FUNCNAMETYPE("CdlConflict::has_no_solution", "result %d");
    CYG_REPORT_FUNCARG1XV(this);
    CYG_PRECONDITION_THISC();

    bool result = no_solution;
    
    CYG_REPORT_RETVAL(result);
    return result;
}

const std::vector<std::pair<CdlValuable, CdlValue> >&
CdlConflictBody::get_solution() const
{
    CYG_REPORT_FUNCNAME("CdlConflict::get_solution");
    CYG_REPORT_FUNCARG1XV(this);
    CYG_PRECONDITION_THISC();

    CYG_REPORT_RETURN();
    return solution;
}

const std::set<CdlValuable>&
CdlConflictBody::get_solution_references() const
{
    CYG_REPORT_FUNCNAME("CdlConflict::get_solution_references");
    CYG_REPORT_FUNCARG1XV(this);
    CYG_PRECONDITION_THISC();

    CYG_REPORT_RETURN();
    return solution_references;
}

// ----------------------------------------------------------------------------
// Try to resolve a conflict. If the conflict was created in a transaction,
// use that transaction. More commonly the conflict will be global and
// a new transaction will have to be created specially for it. Either
// way the conflict may cease to exist.
void
CdlConflictBody::resolve()
{
    CYG_REPORT_FUNCNAME("CdlConflict::resolve");
    CYG_REPORT_FUNCARG1XV(this);
    CYG_PRECONDITION_THISC();
    CYG_PRECONDITIONC(0 == transaction);

    if (this->resolution_implemented()) {
        CdlTransaction transact = CdlTransactionBody::make(this->get_node()->get_toplevel());
        transact->resolve(this);
        transact->body();
        delete transact;
    }
    
    CYG_REPORT_RETURN();
}

// ----------------------------------------------------------------------------
// A valuable has just been changed. If this value was relevant to the
// current solution (or lack thereof) then an update is necessary.
void
CdlConflictBody::update_solution_validity(CdlValuable valuable)
{
    CYG_REPORT_FUNCNAME("CdlConflict::update_solution_validity");
    CYG_REPORT_FUNCARG2XV(this, valuable);
    CYG_PRECONDITION_THISC();

    if (solution_references.find(valuable) != solution_references.end()) {
        no_solution = false;
        solution.clear();
        solution_references.clear();
    }

    CYG_REPORT_RETURN();
}

// ----------------------------------------------------------------------------
// Default implementations of the inference engine do not do a lot...
bool
CdlConflictBody::inner_resolve(CdlTransaction trans_arg, int level)
{
    CYG_REPORT_FUNCNAMETYPE("CdlConflict::inner_resolve", "result false");
    CYG_REPORT_FUNCARG3XV(this, trans_arg, level);
    CYG_PRECONDITION_THISC();
    CYG_PRECONDITION_CLASSC(trans_arg);

    // Setting the no_solution flag while keeping a clear
    // solution_accessed vector means that the no_solution flag should
    // always remain set, and hence no further inference attempts will be made.
    no_solution = true;
    
    CYG_REPORT_RETURN();
    return false;
}

bool
CdlConflictBody::resolution_implemented() const
{
    CYG_REPORT_FUNCNAMETYPE("CdlConflict::resolution_implemented", "result %d");
    CYG_REPORT_FUNCARG1XV(this);
    CYG_PRECONDITION_THISC();

    CYG_REPORT_RETVAL(false);
    return false;
}

// ----------------------------------------------------------------------------
// Clearing a solution. This is needed if the inference engine has
// failed to find a complete solution, because in attempting this the
// solution_references vector will have been filled in anyway. It may
// have some other uses as well.
void
CdlConflictBody::clear_solution()
{
    CYG_REPORT_FUNCNAME("CdlConflict::clear_solution");
    CYG_REPORT_FUNCARG1XV(this);
    CYG_PRECONDITION_THISC();

    no_solution = false;
    solution.clear();
    solution_references.clear();

    CYG_REPORT_RETURN();
}

//}}}
//{{{  Basics                                   

// ----------------------------------------------------------------------------

CdlNode
CdlConflictBody::get_node() const
{
    CYG_REPORT_FUNCNAMETYPE("CdlConflict::get_node", "result %p");
    CYG_REPORT_FUNCARG1XV(this);
    CYG_PRECONDITION_THISC();

    CdlNode result = node;
    CYG_REPORT_RETVAL(result);
    return result;
}

CdlProperty
CdlConflictBody::get_property() const
{
    CYG_REPORT_FUNCNAMETYPE("CdlConflict::get_property", "result %p");
    CYG_REPORT_FUNCARG1XV(this);
    CYG_PRECONDITION_THISC();

    CdlProperty result  = property;
    CYG_REPORT_RETVAL(result);
    return result;
}

bool
CdlConflictBody::is_structural() const
{
    CYG_REPORT_FUNCNAMETYPE("CdlConflict::is_structural", "result %d");
    CYG_REPORT_FUNCARG1XV(this);
    CYG_PRECONDITION_THISC();

    bool result = structural;
    CYG_REPORT_RETVAL(result);
    return result;
}

CdlTransaction
CdlConflictBody::get_transaction() const
{
    CYG_REPORT_FUNCNAMETYPE("CdlConflict::get_transaction", "result %p");
    CYG_REPORT_FUNCARG1XV(this);
    CYG_PRECONDITION_THISC();

    CdlTransaction result = transaction;
    CYG_REPORT_RETVAL(result);
    return result;
}