[GR-79395] Support select.poll

graalpython/com.oracle.graal.python.test/src/tests/unittest_tags/test_poll.txt

@@ -0,0 +1,6 @@
+test.test_poll.PollTests.test_poll1 @ darwin-arm64,linux-aarch64,linux-x86_64
+test.test_poll.PollTests.test_poll2 @ darwin-arm64,linux-aarch64,linux-x86_64
+test.test_poll.PollTests.test_poll3 @ darwin-arm64,linux-aarch64,linux-x86_64
+test.test_poll.PollTests.test_poll_blocks_with_negative_ms @ darwin-arm64,linux-aarch64,linux-x86_64
+test.test_poll.PollTests.test_poll_unit_tests @ darwin-arm64,linux-aarch64,linux-x86_64
+test.test_poll.PollTests.test_threaded_poll @ darwin-arm64,linux-aarch64,linux-x86_64

graalpython/com.oracle.graal.python.test/src/tests/unittest_tags/test_selectors.txt

@@ -17,6 +17,7 @@ test.test_selectors.DefaultSelectorTestCase.test_unregister @ darwin-arm64,linux
 test.test_selectors.DefaultSelectorTestCase.test_unregister_after_fd_close @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github,win32-AMD64,win32-AMD64-github
 test.test_selectors.DefaultSelectorTestCase.test_unregister_after_fd_close_and_reuse @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
 test.test_selectors.DefaultSelectorTestCase.test_unregister_after_socket_close @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github,win32-AMD64,win32-AMD64-github
+test.test_selectors.PollSelectorTestCase.test_select_interrupt_noraise @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github
 test.test_selectors.SelectSelectorTestCase.test_close @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github,win32-AMD64,win32-AMD64-github
 test.test_selectors.SelectSelectorTestCase.test_context_manager @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github,win32-AMD64,win32-AMD64-github
 test.test_selectors.SelectSelectorTestCase.test_empty_select @ darwin-arm64,linux-aarch64,linux-aarch64-github,linux-x86_64,linux-x86_64-github

graalpython/com.oracle.graal.python/AGENTS.md

@@ -26,6 +26,7 @@ com.oracle.graal.python/
 ## CONVENTIONS
 - Code style enforced via pre-commit Eclipse formatter + checkstyle; don’t hand-format Java.
 - Keep naming/layout close to CPython where practical (helps cross-referencing).
+- Put user-facing error and warning message strings in `src/com/oracle/graal/python/nodes/ErrorMessages.java`; reuse an existing constant when possible instead of inlining message literals at call sites.
 
 ## ANTI-PATTERNS
 - Don’t edit generated sources under `mxbuild/**` or distribution outputs; edit `src/**`.

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/Python3Core.java

@@ -63,6 +63,8 @@
 import java.util.Map.Entry;
 import java.util.logging.Level;
 
+import org.graalvm.nativeimage.ImageInfo;
+
 import com.oracle.graal.python.PythonLanguage;
 import com.oracle.graal.python.annotations.PythonOS;
 import com.oracle.graal.python.builtins.modules.AbcModuleBuiltins;
@@ -75,7 +77,6 @@
 import com.oracle.graal.python.builtins.modules.CodecsModuleBuiltins;
 import com.oracle.graal.python.builtins.modules.CodecsTruffleModuleBuiltins;
 import com.oracle.graal.python.builtins.modules.CollectionsModuleBuiltins;
-import com.oracle.graal.python.builtins.modules.codecs.CodecsRegistry;
 import com.oracle.graal.python.builtins.modules.ContextvarsModuleBuiltins;
 import com.oracle.graal.python.builtins.modules.ErrnoModuleBuiltins;
 import com.oracle.graal.python.builtins.modules.FaulthandlerModuleBuiltins;
@@ -99,7 +100,6 @@
 import com.oracle.graal.python.builtins.modules.PosixShMemModuleBuiltins;
 import com.oracle.graal.python.builtins.modules.PosixSubprocessModuleBuiltins;
 import com.oracle.graal.python.builtins.modules.PwdModuleBuiltins;
-import com.oracle.graal.python.builtins.modules.pyexpat.PyExpatModuleBuiltins;
 import com.oracle.graal.python.builtins.modules.QueueModuleBuiltins;
 import com.oracle.graal.python.builtins.modules.RandomModuleBuiltins;
 import com.oracle.graal.python.builtins.modules.ReadlineModuleBuiltins;
@@ -142,6 +142,7 @@
 import com.oracle.graal.python.builtins.modules.cjkcodecs.MultibyteStreamReaderBuiltins;
 import com.oracle.graal.python.builtins.modules.cjkcodecs.MultibyteStreamWriterBuiltins;
 import com.oracle.graal.python.builtins.modules.cjkcodecs.MultibytecodecModuleBuiltins;
+import com.oracle.graal.python.builtins.modules.codecs.CodecsRegistry;
 import com.oracle.graal.python.builtins.modules.csv.CSVDialectBuiltins;
 import com.oracle.graal.python.builtins.modules.csv.CSVModuleBuiltins;
 import com.oracle.graal.python.builtins.modules.csv.CSVReaderBuiltins;
@@ -202,6 +203,8 @@
 import com.oracle.graal.python.builtins.modules.pickle.PicklerMemoProxyBuiltins;
 import com.oracle.graal.python.builtins.modules.pickle.UnpicklerBuiltins;
 import com.oracle.graal.python.builtins.modules.pickle.UnpicklerMemoProxyBuiltins;
+import com.oracle.graal.python.builtins.modules.pyexpat.PyExpatModuleBuiltins;
+import com.oracle.graal.python.builtins.modules.pyexpat.XMLParserBuiltins;
 import com.oracle.graal.python.builtins.modules.re.MatchBuiltins;
 import com.oracle.graal.python.builtins.modules.re.PatternBuiltins;
 import com.oracle.graal.python.builtins.modules.re.SREModuleBuiltins;
@@ -215,10 +218,10 @@
 import com.oracle.graal.python.builtins.objects.NotImplementedBuiltins;
 import com.oracle.graal.python.builtins.objects.PNone;
 import com.oracle.graal.python.builtins.objects.array.ArrayBuiltins;
+import com.oracle.graal.python.builtins.objects.asyncio.ANextAwaitableBuiltins;
 import com.oracle.graal.python.builtins.objects.asyncio.AsyncGenSendBuiltins;
 import com.oracle.graal.python.builtins.objects.asyncio.AsyncGenThrowBuiltins;
 import com.oracle.graal.python.builtins.objects.asyncio.AsyncGeneratorBuiltins;
-import com.oracle.graal.python.builtins.objects.asyncio.ANextAwaitableBuiltins;
 import com.oracle.graal.python.builtins.objects.asyncio.CoroutineWrapperBuiltins;
 import com.oracle.graal.python.builtins.objects.bool.BoolBuiltins;
 import com.oracle.graal.python.builtins.objects.bytes.ByteArrayBuiltins;
@@ -347,6 +350,7 @@
 import com.oracle.graal.python.builtins.objects.range.RangeBuiltins;
 import com.oracle.graal.python.builtins.objects.referencetype.ReferenceTypeBuiltins;
 import com.oracle.graal.python.builtins.objects.reversed.ReversedBuiltins;
+import com.oracle.graal.python.builtins.objects.select.PollBuiltins;
 import com.oracle.graal.python.builtins.objects.set.BaseSetBuiltins;
 import com.oracle.graal.python.builtins.objects.set.FrozenSetBuiltins;
 import com.oracle.graal.python.builtins.objects.set.SetBuiltins;
@@ -371,7 +375,6 @@
 import com.oracle.graal.python.builtins.objects.tuple.InstantiableStructSequenceBuiltins;
 import com.oracle.graal.python.builtins.objects.tuple.StructSequenceBuiltins;
 import com.oracle.graal.python.builtins.objects.tuple.TupleBuiltins;
-import com.oracle.graal.python.builtins.modules.pyexpat.XMLParserBuiltins;
 import com.oracle.graal.python.builtins.objects.tuple.TupleGetterBuiltins;
 import com.oracle.graal.python.builtins.objects.type.PythonBuiltinClass;
 import com.oracle.graal.python.builtins.objects.type.PythonManagedClass;
@@ -422,7 +425,6 @@
 import com.oracle.truffle.api.object.Shape;
 import com.oracle.truffle.api.source.Source;
 import com.oracle.truffle.api.strings.TruffleString;
-import org.graalvm.nativeimage.ImageInfo;
 
 /**
  * The core is a historical artifact and PythonContext and Python3Core should be merged.
@@ -674,6 +676,7 @@ private static PythonBuiltins[] initializeBuiltins(TruffleLanguage.Env env) {
                         new XMLParserBuiltins(),
                         new AstModuleBuiltins(),
                         PythonImageBuildOptions.WITHOUT_NATIVE_POSIX && (PythonImageBuildOptions.WITHOUT_JAVA_INET || !env.isSocketIOAllowed()) ? null : new SelectModuleBuiltins(),
+                        PythonImageBuildOptions.WITHOUT_NATIVE_POSIX && (PythonImageBuildOptions.WITHOUT_JAVA_INET || !env.isSocketIOAllowed()) ? null : new PollBuiltins(),
                         PythonImageBuildOptions.WITHOUT_NATIVE_POSIX && (PythonImageBuildOptions.WITHOUT_JAVA_INET || !env.isSocketIOAllowed()) ? null : new SocketModuleBuiltins(),
                         PythonImageBuildOptions.WITHOUT_NATIVE_POSIX && (PythonImageBuildOptions.WITHOUT_JAVA_INET || !env.isSocketIOAllowed()) ? null : new SocketBuiltins(),
                         PythonImageBuildOptions.WITHOUT_PLATFORM_ACCESS ? null : new SignalModuleBuiltins(),

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/PythonBuiltinClassType.java

@@ -563,6 +563,7 @@ def x(self):
                                     --
 
                                     Simple, unbounded, reentrant FIFO queue.""")),
+    PPoll("poll", PythonObject, newBuilder().moduleName("select").disallowInstantiation()),
     PRandom("Random", PythonObject, newBuilder().publishInModule("_random").basetype().slots(RandomBuiltins.SLOTS)),
     PRange("range", PythonObject, newBuilder().publishInModule(J_BUILTINS).slots(RangeBuiltins.SLOTS).doc("""
                     range(stop) -> range object

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/SelectModuleBuiltins.java

@@ -48,11 +48,14 @@
 
 import com.oracle.graal.python.PythonLanguage;
 import com.oracle.graal.python.annotations.Builtin;
+import com.oracle.graal.python.annotations.PythonOS;
 import com.oracle.graal.python.builtins.CoreFunctions;
 import com.oracle.graal.python.builtins.Python3Core;
 import com.oracle.graal.python.builtins.PythonBuiltinClassType;
 import com.oracle.graal.python.builtins.PythonBuiltins;
+import com.oracle.graal.python.builtins.objects.exception.OSErrorEnum;
 import com.oracle.graal.python.builtins.objects.list.PList;
+import com.oracle.graal.python.builtins.objects.select.PPoll;
 import com.oracle.graal.python.builtins.objects.tuple.PTuple;
 import com.oracle.graal.python.lib.PyObjectAsFileDescriptor;
 import com.oracle.graal.python.lib.PyObjectGetItem;
@@ -74,6 +77,7 @@
 import com.oracle.graal.python.runtime.PosixSupportLibrary.PosixException;
 import com.oracle.graal.python.runtime.PosixSupportLibrary.SelectResult;
 import com.oracle.graal.python.runtime.PosixSupportLibrary.Timeval;
+import com.oracle.graal.python.runtime.PythonContext;
 import com.oracle.graal.python.runtime.exception.PythonErrorType;
 import com.oracle.graal.python.runtime.object.PFactory;
 import com.oracle.graal.python.util.ArrayBuilder;
@@ -94,15 +98,6 @@
 @CoreFunctions(defineModule = "select")
 public final class SelectModuleBuiltins extends PythonBuiltins {
 
-    /*
-     * ATTENTION: if we ever add "poll" support, update the code in
-     * MultiprocessingModuleBuilins#SelectNode to use it if available
-     */
-
-    public SelectModuleBuiltins() {
-        addBuiltinConstant("error", PythonErrorType.OSError);
-    }
-
     @Override
     protected List<? extends NodeFactory<? extends PythonBuiltinBaseNode>> getNodeFactories() {
         return SelectModuleBuiltinsFactory.getFactories();
@@ -111,9 +106,25 @@ protected List<? extends NodeFactory<? extends PythonBuiltinBaseNode>> getNodeFa
     @Override
     public void initialize(Python3Core core) {
         super.initialize(core);
+        addBuiltinConstant("error", PythonErrorType.OSError);
         if (PosixConstants.PIPE_BUF.defined) {
             addBuiltinConstant("PIPE_BUF", PosixConstants.PIPE_BUF.getValueIfDefined());
         }
+        for (PosixConstants.IntConstant constant : PosixConstants.pollFlags) {
+            if (constant.defined) {
+                addBuiltinConstant(constant.name, constant.getValueIfDefined());
+            }
+        }
+    }
+
+    @Builtin(name = "poll", minNumOfPositionalArgs = 0, os = PythonOS.PLATFORM_LINUX)
+    @Builtin(name = "poll", minNumOfPositionalArgs = 0, os = PythonOS.PLATFORM_DARWIN)
+    @GenerateNodeFactory
+    abstract static class PollNode extends PythonBuiltinNode {
+        @Specialization
+        static PPoll poll(@Bind PythonLanguage language) {
+            return PFactory.createPoll(language);
+        }
     }
 
     @Builtin(name = "select", minNumOfPositionalArgs = 3, parameterNames = {"rlist", "wlist", "xlist", "timeout"})
@@ -139,29 +150,48 @@ static PTuple doGeneric(VirtualFrame frame, Object rlist, Object wlist, Object x
             ObjAndFDList xFDs = seq2set(frame, inliningTarget, xlist, sizeNode, asFileDescriptor, callGetItemNode, constructListNode, raiseNode);
 
             Timeval timeoutval = null;
+            long timeoutNs = -1;
             if (!PGuards.isPNone(timeout)) {
                 isNotNoneTimeout.enter(inliningTarget);
-                timeoutval = TimeUtils.pyTimeAsTimeval(pyTimeFromObjectNode.execute(frame, inliningTarget, timeout, RoundType.TIMEOUT, SEC_TO_NS));
+                timeoutNs = pyTimeFromObjectNode.execute(frame, inliningTarget, timeout, RoundType.TIMEOUT, SEC_TO_NS);
+                timeoutval = TimeUtils.pyTimeAsTimeval(timeoutNs);
                 if (timeoutval.getSeconds() < 0) {
                     throw raiseNode.raise(inliningTarget, PythonBuiltinClassType.ValueError, ErrorMessages.MUST_BE_NON_NEGATIVE, "timeout");
                 }
             }
 
             SelectResult result;
-            try {
-                gil.release(true);
+            long startNano = timeoutval != null ? System.nanoTime() : 0;
+            while (true) {
                 try {
-                    result = posixLib.select(PosixSupport.get(inliningTarget), readFDs.fds, writeFDs.fds, xFDs.fds, timeoutval);
-                } finally {
-                    gil.acquire();
+                    gil.release(true);
+                    try {
+                        result = posixLib.select(PosixSupport.get(inliningTarget), readFDs.fds, writeFDs.fds, xFDs.fds, timeoutval);
+                    } finally {
+                        gil.acquire();
+                    }
+                    break;
+                } catch (ChannelNotSelectableException e) {
+                    // GraalPython hack: if one of the channels is not selectable (can happen only
+                    // in the emulated mode), we just return everything.
+                    notSelectableBranch.enter(inliningTarget);
+                    return PFactory.createTuple(language, new Object[]{rlist, wlist, xlist});
+                } catch (PosixException e) {
+                    if (!e.hasErrno(OSErrorEnum.EINTR)) {
+                        throw constructAndRaiseNode.get(inliningTarget).raiseOSErrorFromPosixException(frame, e);
+                    }
+                    PythonContext.triggerAsyncActions(inliningTarget);
+                    if (timeoutval != null) {
+                        long remainingNs = timeoutNs - (System.nanoTime() - startNano);
+                        if (remainingNs <= 0) {
+                            return PFactory.createTuple(language, new PList[]{
+                                            PFactory.createList(language),
+                                            PFactory.createList(language),
+                                            PFactory.createList(language)});
+                        }
+                        timeoutval = TimeUtils.pyTimeAsTimeval(remainingNs);
+                    }
                 }
-            } catch (ChannelNotSelectableException e) {
-                // GraalPython hack: if one of the channels is not selectable (can happen only in
-                // the emulated mode), we just return everything.
-                notSelectableBranch.enter(inliningTarget);
-                return PFactory.createTuple(language, new Object[]{rlist, wlist, xlist});
-            } catch (PosixException e) {
-                throw constructAndRaiseNode.get(inliningTarget).raiseOSErrorFromPosixException(frame, e);
             }
             return PFactory.createTuple(language, new PList[]{
                             toList(result.getReadFds(), readFDs, language),

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/select/PPoll.java

@@ -0,0 +1,126 @@
+/*
+ * Copyright (c) 2026, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * The Universal Permissive License (UPL), Version 1.0
+ *
+ * Subject to the condition set forth below, permission is hereby granted to any
+ * person obtaining a copy of this software, associated documentation and/or
+ * data (collectively the "Software"), free of charge and under any and all
+ * copyright rights in the Software, and any and all patent rights owned or
+ * freely licensable by each licensor hereunder covering either (i) the
+ * unmodified Software as contributed to or provided by such licensor, or (ii)
+ * the Larger Works (as defined below), to deal in both
+ *
+ * (a) the Software, and
+ *
+ * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
+ * one is included with the Software each a "Larger Work" to which the Software
+ * is contributed by such licensors),
+ *
+ * without restriction, including without limitation the rights to copy, create
+ * derivative works of, display, perform, and distribute the Software and make,
+ * use, sell, offer for sale, import, export, have made, and have sold the
+ * Software and the Larger Work(s), and to sublicense the foregoing rights on
+ * either these or other terms.
+ *
+ * This license is subject to the following condition:
+ *
+ * The above copyright notice and either this complete permission notice or at a
+ * minimum a reference to the UPL must be included in all copies or substantial
+ * portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package com.oracle.graal.python.builtins.objects.select;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import com.oracle.graal.python.builtins.objects.object.PythonBuiltinObject;
+import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
+import com.oracle.truffle.api.object.Shape;
+
+public final class PPoll extends PythonBuiltinObject {
+    private final Map<Integer, Integer> registrations;
+    private int[] pollFds;
+    private int[] pollEvents;
+    private int[] pollRevents;
+    private boolean pollDataUpToDate;
+    private boolean pollRunning;
+
+    @TruffleBoundary
+    public PPoll(Object cls, Shape instanceShape) {
+        super(cls, instanceShape);
+        registrations = new LinkedHashMap<>();
+    }
+
+    @TruffleBoundary
+    public synchronized void register(int fd, int events) {
+        registrations.put(fd, events);
+        pollDataUpToDate = false;
+    }
+
+    @TruffleBoundary
+    public synchronized boolean modify(int fd, int events) {
+        if (!registrations.containsKey(fd)) {
+            return false;
+        }
+        registrations.put(fd, events);
+        pollDataUpToDate = false;
+        return true;
+    }
+
+    @TruffleBoundary
+    public synchronized boolean unregister(int fd) {
+        if (registrations.remove(fd) == null) {
+            return false;
+        }
+        pollDataUpToDate = false;
+        return true;
+    }
+
+    @TruffleBoundary
+    public synchronized boolean startPoll() {
+        if (pollRunning) {
+            return false;
+        }
+        if (!pollDataUpToDate) {
+            pollFds = new int[registrations.size()];
+            pollEvents = new int[registrations.size()];
+            pollRevents = new int[registrations.size()];
+            int i = 0;
+            for (Map.Entry<Integer, Integer> entry : registrations.entrySet()) {
+                pollFds[i] = entry.getKey();
+                pollEvents[i] = entry.getValue();
+                i++;
+            }
+            pollDataUpToDate = true;
+        }
+        pollRunning = true;
+        return true;
+    }
+
+    public int[] getPollFds() {
+        return pollFds;
+    }
+
+    public int[] getPollEvents() {
+        return pollEvents;
+    }
+
+    public int[] getPollRevents() {
+        return pollRevents;
+    }
+
+    @TruffleBoundary
+    public synchronized void finishPoll() {
+        pollRunning = false;
+    }
+}