1 files changed, 202 insertions, 0 deletions
diff --git a/test/syscalls/linux/lseek.cc b/test/syscalls/linux/lseek.cc
new file mode 100644
index 000000000..fb6a1546e
--- /dev/null
+++ b/test/syscalls/linux/lseek.cc
@@ -0,0 +1,202 @@
+// 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 <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "gtest/gtest.h"
+#include "test/util/file_descriptor.h"
+#include "test/util/temp_path.h"
+#include "test/util/test_util.h"
+
+namespace gvisor {
+namespace testing {
+
+namespace {
+
+TEST(LseekTest, InvalidWhence) {
+  const std::string kFileData = "hello world\n";
+  const TempPath path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith(
+      GetAbsoluteTestTmpdir(), kFileData, TempPath::kDefaultFileMode));
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDWR, 0644));
+
+  ASSERT_THAT(lseek(fd.get(), 0, -1), SyscallFailsWithErrno(EINVAL));
+}
+
+TEST(LseekTest, NegativeOffset) {
+  const std::string kFileData = "hello world\n";
+  const TempPath path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith(
+      GetAbsoluteTestTmpdir(), kFileData, TempPath::kDefaultFileMode));
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDWR, 0644));
+
+  EXPECT_THAT(lseek(fd.get(), -(kFileData.length() + 1), SEEK_CUR),
+              SyscallFailsWithErrno(EINVAL));
+}
+
+// A 32-bit off_t is not large enough to represent an offset larger than
+// maximum file size on standard file systems, so it isn't possible to cause
+// overflow.
+#ifdef __x86_64__
+TEST(LseekTest, Overflow) {
+  // HA! Classic Linux. We really should have an EOVERFLOW
+  // here, since we're seeking to something that cannot be
+  // represented.. but instead we are given an EINVAL.
+  const std::string kFileData = "hello world\n";
+  const TempPath path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith(
+      GetAbsoluteTestTmpdir(), kFileData, TempPath::kDefaultFileMode));
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDWR, 0644));
+  EXPECT_THAT(lseek(fd.get(), 0x7fffffffffffffff, SEEK_END),
+              SyscallFailsWithErrno(EINVAL));
+}
+#endif
+
+TEST(LseekTest, Set) {
+  const std::string kFileData = "hello world\n";
+  const TempPath path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith(
+      GetAbsoluteTestTmpdir(), kFileData, TempPath::kDefaultFileMode));
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDWR, 0644));
+
+  char buf = '\0';
+  EXPECT_THAT(lseek(fd.get(), 0, SEEK_SET), SyscallSucceedsWithValue(0));
+  ASSERT_THAT(read(fd.get(), &buf, 1), SyscallSucceedsWithValue(1));
+  EXPECT_EQ(buf, kFileData.c_str()[0]);
+  EXPECT_THAT(lseek(fd.get(), 6, SEEK_SET), SyscallSucceedsWithValue(6));
+  ASSERT_THAT(read(fd.get(), &buf, 1), SyscallSucceedsWithValue(1));
+  EXPECT_EQ(buf, kFileData.c_str()[6]);
+}
+
+TEST(LseekTest, Cur) {
+  const std::string kFileData = "hello world\n";
+  const TempPath path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith(
+      GetAbsoluteTestTmpdir(), kFileData, TempPath::kDefaultFileMode));
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDWR, 0644));
+
+  char buf = '\0';
+  EXPECT_THAT(lseek(fd.get(), 0, SEEK_SET), SyscallSucceedsWithValue(0));
+  ASSERT_THAT(read(fd.get(), &buf, 1), SyscallSucceedsWithValue(1));
+  EXPECT_EQ(buf, kFileData.c_str()[0]);
+  EXPECT_THAT(lseek(fd.get(), 3, SEEK_CUR), SyscallSucceedsWithValue(4));
+  ASSERT_THAT(read(fd.get(), &buf, 1), SyscallSucceedsWithValue(1));
+  EXPECT_EQ(buf, kFileData.c_str()[4]);
+}
+
+TEST(LseekTest, End) {
+  const std::string kFileData = "hello world\n";
+  const TempPath path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith(
+      GetAbsoluteTestTmpdir(), kFileData, TempPath::kDefaultFileMode));
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDWR, 0644));
+
+  char buf = '\0';
+  EXPECT_THAT(lseek(fd.get(), 0, SEEK_SET), SyscallSucceedsWithValue(0));
+  ASSERT_THAT(read(fd.get(), &buf, 1), SyscallSucceedsWithValue(1));
+  EXPECT_EQ(buf, kFileData.c_str()[0]);
+  EXPECT_THAT(lseek(fd.get(), -2, SEEK_END), SyscallSucceedsWithValue(10));
+  ASSERT_THAT(read(fd.get(), &buf, 1), SyscallSucceedsWithValue(1));
+  EXPECT_EQ(buf, kFileData.c_str()[kFileData.length() - 2]);
+}
+
+TEST(LseekTest, InvalidFD) {
+  EXPECT_THAT(lseek(-1, 0, SEEK_SET), SyscallFailsWithErrno(EBADF));
+}
+
+TEST(LseekTest, DirCurEnd) {
+  const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open("/tmp", O_RDONLY));
+  ASSERT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0));
+}
+
+TEST(LseekTest, ProcDir) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/proc/self", O_RDONLY));
+  ASSERT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceeds());
+  ASSERT_THAT(lseek(fd.get(), 0, SEEK_END), SyscallSucceeds());
+}
+
+TEST(LseekTest, ProcFile) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/proc/meminfo", O_RDONLY));
+  ASSERT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceeds());
+  ASSERT_THAT(lseek(fd.get(), 0, SEEK_END), SyscallFailsWithErrno(EINVAL));
+}
+
+TEST(LseekTest, SysDir) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/sys/devices", O_RDONLY));
+  ASSERT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceeds());
+  ASSERT_THAT(lseek(fd.get(), 0, SEEK_END), SyscallSucceeds());
+}
+
+TEST(LseekTest, SeekCurrentDir) {
+  // From include/linux/fs.h.
+  constexpr loff_t MAX_LFS_FILESIZE = 0x7fffffffffffffff;
+
+  char* dir = get_current_dir_name();
+  const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(dir, O_RDONLY));
+
+  ASSERT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceeds());
+  ASSERT_THAT(lseek(fd.get(), 0, SEEK_END),
+              // Some filesystems (like ext4) allow lseek(SEEK_END) on a
+              // directory and return MAX_LFS_FILESIZE, others return EINVAL.
+              AnyOf(SyscallSucceedsWithValue(MAX_LFS_FILESIZE),
+                    SyscallFailsWithErrno(EINVAL)));
+  free(dir);
+}
+
+TEST(LseekTest, ProcStatTwice) {
+  const FileDescriptor fd1 =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/proc/stat", O_RDONLY));
+  const FileDescriptor fd2 =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/proc/stat", O_RDONLY));
+
+  ASSERT_THAT(lseek(fd1.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0));
+  ASSERT_THAT(lseek(fd1.get(), 0, SEEK_END), SyscallFailsWithErrno(EINVAL));
+  ASSERT_THAT(lseek(fd1.get(), 1000, SEEK_CUR), SyscallSucceeds());
+  // Check that just because we moved fd1, fd2 doesn't move.
+  ASSERT_THAT(lseek(fd2.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0));
+
+  const FileDescriptor fd3 =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/proc/stat", O_RDONLY));
+  ASSERT_THAT(lseek(fd3.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0));
+}
+
+TEST(LseekTest, EtcPasswdDup) {
+  const FileDescriptor fd1 =
+      ASSERT_NO_ERRNO_AND_VALUE(Open("/etc/passwd", O_RDONLY));
+  const FileDescriptor fd2 = ASSERT_NO_ERRNO_AND_VALUE(fd1.Dup());
+
+  ASSERT_THAT(lseek(fd1.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0));
+  ASSERT_THAT(lseek(fd2.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0));
+  ASSERT_THAT(lseek(fd1.get(), 1000, SEEK_CUR), SyscallSucceeds());
+  // Check that just because we moved fd1, fd2 doesn't move.
+  ASSERT_THAT(lseek(fd2.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(1000));
+
+  const FileDescriptor fd3 = ASSERT_NO_ERRNO_AND_VALUE(fd1.Dup());
+  ASSERT_THAT(lseek(fd3.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(1000));
+}
+
+// TODO: Add tests where we have donated in sockets.
+
+}  // namespace
+
+}  // namespace testing
+}  // namespace gvisor