1 files changed, 55 insertions, 0 deletions
diff --git a/pkg/sentry/syscalls/linux/sys_lseek.go b/pkg/sentry/syscalls/linux/sys_lseek.go
new file mode 100644
index 000000000..97b51ba7c
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/sys_lseek.go
@@ -0,0 +1,55 @@
+// Copyright 2018 Google Inc.
+//
+// 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 linux
+
+import (
+	"gvisor.googlesource.com/gvisor/pkg/sentry/arch"
+	"gvisor.googlesource.com/gvisor/pkg/sentry/fs"
+	"gvisor.googlesource.com/gvisor/pkg/sentry/kernel"
+	"gvisor.googlesource.com/gvisor/pkg/sentry/kernel/kdefs"
+	"gvisor.googlesource.com/gvisor/pkg/syserror"
+)
+
+// Lseek implements linux syscall lseek(2).
+func Lseek(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+	fd := kdefs.FD(args[0].Int())
+	offset := args[1].Int64()
+	whence := args[2].Int()
+
+	file := t.FDMap().GetFile(fd)
+	if file == nil {
+		return 0, nil, syserror.EBADF
+	}
+	defer file.DecRef()
+
+	var sw fs.SeekWhence
+	switch whence {
+	case 0:
+		sw = fs.SeekSet
+	case 1:
+		sw = fs.SeekCurrent
+	case 2:
+		sw = fs.SeekEnd
+	default:
+		return 0, nil, syserror.EINVAL
+	}
+
+	offset, serr := file.Seek(t, sw, offset)
+	err := handleIOError(t, false /* partialResult */, serr, kernel.ERESTARTSYS, "lseek", file)
+	if err != nil {
+		return 0, nil, err
+	}
+	return uintptr(offset), nil, err
+}