SquirrelJME/SquirrelJME

// -*- Mode: Java; indent-tabs-mode: t; tab-width: 4 -*-
// ---------------------------------------------------------------------------
// Multi-Phasic Applications: SquirrelJME
//     Copyright (C) Stephanie Gawroriski <xer@multiphasicapps.net>
// ---------------------------------------------------------------------------
// SquirrelJME is under the Mozilla Public License Version 2.0.
// See license.mkd for licensing and copyright information.
// ---------------------------------------------------------------------------

package cc.squirreljme.debugger;

import cc.squirreljme.jdwp.JDWPCommandSetVirtualMachine;
import cc.squirreljme.jdwp.JDWPCapability;
import cc.squirreljme.jdwp.JDWPCommandSet;
import cc.squirreljme.jdwp.JDWPPacket;
import java.util.HashSet;
import java.util.Set;

/**
 * This contains the status of capabilities of the connected virtual machine.
 *
 * @since 2024/01/19
 */
public class CapabilityStatus
    implements ReplyHandler
{
    /** The currently set capabilities. */
    private final Set<JDWPCapability> _capabilities =
        new HashSet<>()/*new EnumSet<>(JDWPCapability.class)*/;
    
    /**
     * {@inheritDoc}
     * @since 2024/01/19
     */
    @Override
    public void handlePacket(DebuggerState __debuggerState,
        JDWPPacket __packet)
        throws NullPointerException
    {
        if (__debuggerState == null || __packet == null)
            throw new NullPointerException("NARG");
        
        Set<JDWPCapability> capabilities = this._capabilities;
        synchronized (this)
        {
            // Go through all capabilities listed in the packet to update
            for (int id = 0, n = __packet.length(); id < n; id++)
            {
                // Only accept valid capabilities
                JDWPCapability capability = JDWPCapability.of(id);
                if (capability == null)
                    continue;
                
                // Either set or clear the capability
                if (__packet.readBoolean())
                    capabilities.add(capability);
                else
                    capabilities.remove(capability);
            }
        }
    }
    
    /**
     * Is the given capability set?
     *
     * @param __cap The capability to check.
     * @return If the capability is set.
     * @throws NullPointerException On null arguments.
     * @since 2024/01/19
     */
    public boolean has(JDWPCapability __cap)
        throws NullPointerException
    {
        if (__cap == null)
            throw new NullPointerException("NARG");
        
        synchronized (this)
        {
            return this._capabilities.contains(__cap);
        }
    }
    
    /**
     * Requests an update of capabilities of the remote virtual machine.
     *
     * @param __state The current debugging state.
     * @throws NullPointerException On null arguments.
     * @since 2024/01/19
     */
    public void update(DebuggerState __state)
        throws NullPointerException
    {
        if (__state == null)
            throw new NullPointerException("NARG");
        
        // Ask for normal capabilities (older VM)
        try (JDWPPacket out = __state.commLink.request(
            JDWPCommandSet.VIRTUAL_MACHINE,
            JDWPCommandSetVirtualMachine.CAPABILITIES))
        {
            __state.send(out, this, ReplyHandler.IGNORED);
        }
        
        // Ask for newer capabilities (newer VM)
        try (JDWPPacket out = __state.commLink.request(
            JDWPCommandSet.VIRTUAL_MACHINE,
            JDWPCommandSetVirtualMachine.CAPABILITIES_NEW))
        {
            __state.send(out, this, ReplyHandler.IGNORED);
        }
    }
}