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 * (a) the Software, and
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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
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package com.oracle.graal.python.builtins.objects.thread;

import java.util.List;

import com.oracle.graal.python.builtins.Builtin;
import com.oracle.graal.python.builtins.CoreFunctions;
import com.oracle.graal.python.builtins.PythonBuiltinClassType;
import com.oracle.graal.python.builtins.PythonBuiltins;
import com.oracle.graal.python.builtins.objects.PNone;
import com.oracle.graal.python.builtins.objects.common.SequenceStorageNodes;
import com.oracle.graal.python.builtins.objects.tuple.PTuple;
import com.oracle.graal.python.nodes.ErrorMessages;
import com.oracle.graal.python.nodes.function.PythonBuiltinBaseNode;
import com.oracle.graal.python.nodes.function.builtins.PythonBinaryBuiltinNode;
import com.oracle.graal.python.nodes.function.builtins.PythonUnaryBuiltinNode;
import com.oracle.graal.python.nodes.util.CastToJavaUnsignedLongNode;
import com.oracle.graal.python.runtime.GilNode;
import com.oracle.graal.python.runtime.exception.PythonErrorType;
import com.oracle.truffle.api.dsl.Cached;
import com.oracle.truffle.api.dsl.GenerateNodeFactory;
import com.oracle.truffle.api.dsl.NodeFactory;
import com.oracle.truffle.api.dsl.Specialization;
import com.oracle.truffle.api.profiles.ConditionProfile;

@CoreFunctions(extendClasses = PythonBuiltinClassType.PRLock)
public class RLockBuiltins extends PythonBuiltins {
    @Override
    protected List<? extends NodeFactory<? extends PythonBuiltinBaseNode>> getNodeFactories() {
        return RLockBuiltinsFactory.getFactories();
    }

    @Builtin(name = "_is_owned", minNumOfPositionalArgs = 1)
    @GenerateNodeFactory
    abstract static class IsOwnedRLockNode extends PythonUnaryBuiltinNode {
        @Specialization
        boolean isOwned(PRLock self) {
            return self.isOwned();
        }
    }

    @Builtin(name = "_acquire_restore", minNumOfPositionalArgs = 2)
    @GenerateNodeFactory
    abstract static class AcquireRestoreRLockNode extends PythonBinaryBuiltinNode {
        @Specialization
        Object acquireRestore(PRLock self, PTuple state,
                        @Cached GilNode gil,
                        @Cached CastToJavaUnsignedLongNode castLong,
                        @Cached SequenceStorageNodes.GetItemDynamicNode getItemNode) {
            if (!self.acquireNonBlocking()) {
                gil.release(true);
                try {
                    self.acquireBlocking(this);
                } finally {
                    gil.acquire();
                }
            }
            // ignore owner, we use the Java lock and cannot set it
            long count = castLong.execute(getItemNode.execute(state.getSequenceStorage(), 0));
            long actualCount = self.getCount();
            while (count > actualCount) {
                self.acquireBlocking(this); // we already own it at this point
                actualCount++;
            }
            while (count < actualCount) {
                self.release();
                actualCount--;
            }
            return PNone.NONE;
        }
    }

    @Builtin(name = "_release_save", minNumOfPositionalArgs = 1)
    @GenerateNodeFactory
    abstract static class ReleaseSaveRLockNode extends PythonUnaryBuiltinNode {
        @Specialization
        Object releaseSave(PRLock self,
                        @Cached ConditionProfile countProfile) {
            int count = self.getCount();
            if (countProfile.profile(count == 0)) {
                throw raise(PythonErrorType.RuntimeError, ErrorMessages.CANNOT_RELEASE_UNAQUIRED_LOCK);
            }
            PTuple retVal = factory().createTuple(new Object[]{count, self.getOwnerId()});
            self.releaseAll();
            return retVal;
        }
    }
}
