1 files changed, 149 insertions, 0 deletions
diff --git a/test/syscalls/linux/dev.cc b/test/syscalls/linux/dev.cc
new file mode 100644
index 000000000..a140d3b30
--- /dev/null
+++ b/test/syscalls/linux/dev.cc
@@ -0,0 +1,149 @@
+// Copyright 2018 Google LLC
+//
+// 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.
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <vector>
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+#include "test/util/file_descriptor.h"
+#include "test/util/test_util.h"
+
+namespace gvisor {
+namespace testing {
+
+namespace {
+
+TEST(DevTest, LseekDevUrandom) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/urandom", O_RDONLY));
+  EXPECT_THAT(lseek(fd.get(), -10, SEEK_CUR), SyscallSucceeds());
+  EXPECT_THAT(lseek(fd.get(), -10, SEEK_SET), SyscallSucceeds());
+  EXPECT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceeds());
+}
+
+TEST(DevTest, LseekDevNull) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/null", O_RDONLY));
+  EXPECT_THAT(lseek(fd.get(), -10, SEEK_CUR), SyscallSucceeds());
+  EXPECT_THAT(lseek(fd.get(), -10, SEEK_SET), SyscallSucceeds());
+  EXPECT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceeds());
+  EXPECT_THAT(lseek(fd.get(), 0, SEEK_END), SyscallSucceeds());
+}
+
+TEST(DevTest, LseekDevZero) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/zero", O_RDONLY));
+  EXPECT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceeds());
+  EXPECT_THAT(lseek(fd.get(), 0, SEEK_END), SyscallSucceeds());
+}
+
+TEST(DevTest, LseekDevFull) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/full", O_RDONLY));
+  EXPECT_THAT(lseek(fd.get(), 123, SEEK_SET), SyscallSucceedsWithValue(0));
+  EXPECT_THAT(lseek(fd.get(), 123, SEEK_CUR), SyscallSucceedsWithValue(0));
+  EXPECT_THAT(lseek(fd.get(), 123, SEEK_END), SyscallSucceedsWithValue(0));
+}
+
+TEST(DevTest, LseekDevNullFreshFile) {
+  // Seeks to /dev/null always return 0.
+  const FileDescriptor fd1 =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/null", O_RDONLY));
+  const FileDescriptor fd2 =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/null", O_RDONLY));
+
+  EXPECT_THAT(lseek(fd1.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0));
+  EXPECT_THAT(lseek(fd1.get(), 1000, SEEK_CUR), SyscallSucceedsWithValue(0));
+  EXPECT_THAT(lseek(fd2.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0));
+
+  const FileDescriptor fd3 =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/null", O_RDONLY));
+  EXPECT_THAT(lseek(fd3.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0));
+}
+
+TEST(DevTest, OpenTruncate) {
+  // Truncation is ignored on linux and gvisor for device files.
+  ASSERT_NO_ERRNO_AND_VALUE(
+      Open("/dev/null", O_CREAT | O_TRUNC | O_WRONLY, 0644));
+  ASSERT_NO_ERRNO_AND_VALUE(
+      Open("/dev/zero", O_CREAT | O_TRUNC | O_WRONLY, 0644));
+  ASSERT_NO_ERRNO_AND_VALUE(
+      Open("/dev/full", O_CREAT | O_TRUNC | O_WRONLY, 0644));
+}
+
+TEST(DevTest, Pread64DevNull) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/null", O_RDONLY));
+  char buf[1];
+  EXPECT_THAT(pread64(fd.get(), buf, 1, 0), SyscallSucceedsWithValue(0));
+}
+
+TEST(DevTest, Pread64DevZero) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/zero", O_RDONLY));
+  char buf[1];
+  EXPECT_THAT(pread64(fd.get(), buf, 1, 0), SyscallSucceedsWithValue(1));
+}
+
+TEST(DevTest, Pread64DevFull) {
+  // /dev/full behaves like /dev/zero with respect to reads.
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/full", O_RDONLY));
+  char buf[1];
+  EXPECT_THAT(pread64(fd.get(), buf, 1, 0), SyscallSucceedsWithValue(1));
+}
+
+TEST(DevTest, ReadDevNull) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/null", O_RDONLY));
+  std::vector<char> buf(1);
+  EXPECT_THAT(ReadFd(fd.get(), buf.data(), 1), SyscallSucceeds());
+}
+
+// Do not allow random save as it could lead to partial reads.
+TEST(DevTest, ReadDevZero_NoRandomSave) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/zero", O_RDONLY));
+
+  constexpr int kReadSize = 128 * 1024;
+  std::vector<char> buf(kReadSize, 1);
+  EXPECT_THAT(ReadFd(fd.get(), buf.data(), kReadSize),
+              SyscallSucceedsWithValue(kReadSize));
+  EXPECT_EQ(std::vector<char>(kReadSize, 0), buf);
+}
+
+TEST(DevTest, WriteDevNull) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/null", O_WRONLY));
+  EXPECT_THAT(WriteFd(fd.get(), "a", 1), SyscallSucceedsWithValue(1));
+}
+
+TEST(DevTest, WriteDevZero) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/zero", O_WRONLY));
+  EXPECT_THAT(WriteFd(fd.get(), "a", 1), SyscallSucceedsWithValue(1));
+}
+
+TEST(DevTest, WriteDevFull) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/dev/full", O_WRONLY));
+  EXPECT_THAT(WriteFd(fd.get(), "a", 1), SyscallFailsWithErrno(ENOSPC));
+}
+
+}  // namespace
+}  // namespace testing
+
+}  // namespace gvisor