core: grpc-timeout should always be positive

binder/src/main/java/io/grpc/binder/internal/Outbound.java

@@ -19,7 +19,6 @@
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkState;
 import static io.grpc.internal.GrpcUtil.TIMEOUT_KEY;
-import static java.lang.Math.max;
 
 import android.os.Parcel;
 import com.google.errorprone.annotations.concurrent.GuardedBy;
@@ -397,8 +396,7 @@ protected int writeSuffix(Parcel parcel) throws IOException {
     @GuardedBy("this")
     void setDeadline(Deadline deadline) {
       headers.discardAll(TIMEOUT_KEY);
-      long effectiveTimeoutNanos = max(0, deadline.timeRemaining(TimeUnit.NANOSECONDS));
-      headers.put(TIMEOUT_KEY, effectiveTimeoutNanos);
+      headers.put(TIMEOUT_KEY, deadline.timeRemaining(TimeUnit.NANOSECONDS));
     }
   }
 

core/src/main/java/io/grpc/internal/AbstractClientStream.java

@@ -21,7 +21,6 @@
 import static io.grpc.internal.GrpcUtil.CONTENT_ENCODING_KEY;
 import static io.grpc.internal.GrpcUtil.MESSAGE_ENCODING_KEY;
 import static io.grpc.internal.GrpcUtil.TIMEOUT_KEY;
-import static java.lang.Math.max;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
@@ -124,8 +123,7 @@ protected AbstractClientStream(
   @Override
   public void setDeadline(Deadline deadline) {
     headers.discardAll(TIMEOUT_KEY);
-    long effectiveTimeout = max(0, deadline.timeRemaining(TimeUnit.NANOSECONDS));
-    headers.put(TIMEOUT_KEY, effectiveTimeout);
+    headers.put(TIMEOUT_KEY, deadline.timeRemaining(TimeUnit.NANOSECONDS));
   }
 
   @Override

core/src/main/java/io/grpc/internal/GrpcUtil.java

@@ -651,12 +651,14 @@ public Stopwatch get() {
   static class TimeoutMarshaller implements Metadata.AsciiMarshaller<Long> {
 
     @Override
-    public String toAsciiString(Long timeoutNanos) {
+    public String toAsciiString(Long timeoutNanosObject) {
       long cutoff = 100000000;
+      // Timeout checking is inherently racy. RPCs with timeouts in the past ideally don't even get
+      // here, but if the timeout is expired assume that happened recently and adjust it to the
+      // smallest allowed timeout
+      long timeoutNanos = Math.max(1, timeoutNanosObject);
       TimeUnit unit = TimeUnit.NANOSECONDS;
-      if (timeoutNanos < 0) {
-        throw new IllegalArgumentException("Timeout too small");
-      } else if (timeoutNanos < cutoff) {
+      if (timeoutNanos < cutoff) {
         return timeoutNanos + "n";
       } else if (timeoutNanos < cutoff * 1000L) {
         return unit.toMicros(timeoutNanos) + "u";

core/src/test/java/io/grpc/internal/AbstractClientStreamTest.java

@@ -465,6 +465,24 @@ allocator, new BaseTransportState(statsTraceCtx, transportTracer), sink, statsTr
         .isGreaterThan(TimeUnit.MILLISECONDS.toNanos(600));
   }
 
+  @Test
+  public void setDeadline_thePastBecomesPositive() {
+    AbstractClientStream.Sink sink = mock(AbstractClientStream.Sink.class);
+    ClientStream stream = new BaseAbstractClientStream(
+        allocator, new BaseTransportState(statsTraceCtx, transportTracer), sink, statsTraceCtx,
+        transportTracer);
+
+    stream.setDeadline(Deadline.after(-1, TimeUnit.NANOSECONDS));
+    stream.start(mockListener);
+
+    ArgumentCaptor<Metadata> headersCaptor = ArgumentCaptor.forClass(Metadata.class);
+    verify(sink).writeHeaders(headersCaptor.capture(), ArgumentMatchers.<byte[]>any());
+
+    Metadata headers = headersCaptor.getValue();
+    assertThat(headers.get(Metadata.Key.of("grpc-timeout", Metadata.ASCII_STRING_MARSHALLER)))
+        .isEqualTo("1n");
+  }
+
   @Test
   public void appendTimeoutInsight() {
     InsightBuilder insight = new InsightBuilder();

core/src/test/java/io/grpc/internal/GrpcUtilTest.java

@@ -98,8 +98,8 @@ public void timeoutTest() {
     GrpcUtil.TimeoutMarshaller marshaller =
             new GrpcUtil.TimeoutMarshaller();
     // nanos
-    assertEquals("0n", marshaller.toAsciiString(0L));
-    assertEquals(0L, (long) marshaller.parseAsciiString("0n"));
+    assertEquals("1n", marshaller.toAsciiString(1L));
+    assertEquals(1L, (long) marshaller.parseAsciiString("1n"));
 
     assertEquals("99999999n", marshaller.toAsciiString(99999999L));
     assertEquals(99999999L, (long) marshaller.parseAsciiString("99999999n"));

core/src/test/java/io/grpc/internal/ServerImplTest.java

@@ -53,6 +53,7 @@
 import io.grpc.Channel;
 import io.grpc.Compressor;
 import io.grpc.Context;
+import io.grpc.Deadline;
 import io.grpc.Grpc;
 import io.grpc.HandlerRegistry;
 import io.grpc.IntegerMarshaller;
@@ -1146,11 +1147,21 @@ public ServerCall.Listener<String> startCall(
   @Test
   public void testContextExpiredBeforeStreamCreate_StreamCancelNotCalledBeforeSetListener()
       throws Exception {
+    builder.ticker = new Deadline.Ticker() {
+      private long time;
+
+      @Override
+      public long nanoTime() {
+        time += 1000;
+        return time;
+      }
+    };
+
     AtomicBoolean contextCancelled = new AtomicBoolean(false);
     AtomicReference<Context> context = new AtomicReference<>();
     AtomicReference<ServerCall<String, Integer>> callReference = new AtomicReference<>();
 
-    testStreamClose_setup(callReference, context, contextCancelled, 0L);
+    testStreamClose_setup(callReference, context, contextCancelled, 1L);
 
     // This assert that stream.setListener(jumpListener) is called before stream.cancel(), which
     // prevents extremely short deadlines causing NPEs.

inprocess/src/main/java/io/grpc/inprocess/InProcessTransport.java

@@ -18,7 +18,6 @@
 
 import static com.google.common.base.Preconditions.checkNotNull;
 import static io.grpc.internal.GrpcUtil.TIMEOUT_KEY;
-import static java.lang.Math.max;
 
 import com.google.common.base.MoreObjects;
 import com.google.common.io.ByteStreams;
@@ -939,8 +938,7 @@ public void setMaxOutboundMessageSize(int maxSize) {}
       @Override
       public void setDeadline(Deadline deadline) {
         headers.discardAll(TIMEOUT_KEY);
-        long effectiveTimeout = max(0, deadline.timeRemaining(TimeUnit.NANOSECONDS));
-        headers.put(TIMEOUT_KEY, effectiveTimeout);
+        headers.put(TIMEOUT_KEY, deadline.timeRemaining(TimeUnit.NANOSECONDS));
       }
 
       @Override