1 files changed, 52 insertions, 0 deletions
diff --git a/pkg/sentry/strace/futex.go b/pkg/sentry/strace/futex.go
new file mode 100644
index 000000000..24301bda6
--- /dev/null
+++ b/pkg/sentry/strace/futex.go
@@ -0,0 +1,52 @@
+// Copyright 2018 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package strace
+
+import (
+	"gvisor.googlesource.com/gvisor/pkg/abi"
+	"gvisor.googlesource.com/gvisor/pkg/abi/linux"
+)
+
+// FutexCmd are the possible futex(2) commands.
+var FutexCmd = abi.ValueSet{
+	linux.FUTEX_WAIT:            "FUTEX_WAIT",
+	linux.FUTEX_WAKE:            "FUTEX_WAKE",
+	linux.FUTEX_FD:              "FUTEX_FD",
+	linux.FUTEX_REQUEUE:         "FUTEX_REQUEUE",
+	linux.FUTEX_CMP_REQUEUE:     "FUTEX_CMP_REQUEUE",
+	linux.FUTEX_WAKE_OP:         "FUTEX_WAKE_OP",
+	linux.FUTEX_LOCK_PI:         "FUTEX_LOCK_PI",
+	linux.FUTEX_UNLOCK_PI:       "FUTEX_UNLOCK_PI",
+	linux.FUTEX_TRYLOCK_PI:      "FUTEX_TRYLOCK_PI",
+	linux.FUTEX_WAIT_BITSET:     "FUTEX_WAIT_BITSET",
+	linux.FUTEX_WAKE_BITSET:     "FUTEX_WAKE_BITSET",
+	linux.FUTEX_WAIT_REQUEUE_PI: "FUTEX_WAIT_REQUEUE_PI",
+	linux.FUTEX_CMP_REQUEUE_PI:  "FUTEX_CMP_REQUEUE_PI",
+}
+
+func futex(op uint64) string {
+	cmd := op &^ (linux.FUTEX_PRIVATE_FLAG | linux.FUTEX_CLOCK_REALTIME)
+	clockRealtime := (op & linux.FUTEX_CLOCK_REALTIME) == linux.FUTEX_CLOCK_REALTIME
+	private := (op & linux.FUTEX_PRIVATE_FLAG) == linux.FUTEX_PRIVATE_FLAG
+
+	s := FutexCmd.Parse(cmd)
+	if clockRealtime {
+		s += "|FUTEX_CLOCK_REALTIME"
+	}
+	if private {
+		s += "|FUTEX_PRIVATE_FLAG"
+	}
+	return s
+}