1 files changed, 173 insertions, 0 deletions
diff --git a/test/syscalls/linux/mknod.cc b/test/syscalls/linux/mknod.cc
new file mode 100644
index 000000000..361ca299b
--- /dev/null
+++ b/test/syscalls/linux/mknod.cc
@@ -0,0 +1,173 @@
+// 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 <sys/stat.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+#include <vector>
+
+#include "gtest/gtest.h"
+#include "test/util/temp_path.h"
+#include "test/util/test_util.h"
+#include "test/util/thread_util.h"
+
+namespace gvisor {
+namespace testing {
+
+namespace {
+
+TEST(MknodTest, RegularFile) {
+  std::string const node0 = NewTempAbsPathInDir("/tmp");
+  std::string const node1 = NewTempAbsPathInDir("/tmp");
+  ASSERT_THAT(mknod(node0.c_str(), S_IFREG, 0), SyscallSucceeds());
+  ASSERT_THAT(mknod(node1.c_str(), 0, 0), SyscallSucceeds());
+}
+
+TEST(MknodTest, MknodAtRegularFile) {
+  std::string const fifo_relpath = NewTempRelPath();
+  std::string const fifo = JoinPath("/tmp", fifo_relpath);
+  int dirfd;
+  ASSERT_THAT(dirfd = open("/tmp", O_RDONLY), SyscallSucceeds());
+  ASSERT_THAT(mknodat(dirfd, fifo_relpath.c_str(), S_IFIFO | S_IRUSR, 0),
+              SyscallSucceeds());
+  EXPECT_THAT(close(dirfd), SyscallSucceeds());
+
+  struct stat st;
+  ASSERT_THAT(stat(fifo.c_str(), &st), SyscallSucceeds());
+  EXPECT_TRUE(S_ISFIFO(st.st_mode));
+}
+
+TEST(MknodTest, MknodOnExistingPathFails) {
+  std::string const file = NewTempAbsPathInDir("/tmp");
+  std::string const slink = NewTempAbsPathInDir("/tmp");
+  int fd;
+  ASSERT_THAT(fd = open(file.c_str(), O_CREAT | O_RDWR, S_IRUSR | S_IWUSR),
+              SyscallSucceeds());
+  EXPECT_THAT(close(fd), SyscallSucceeds());
+  ASSERT_THAT(symlink(file.c_str(), slink.c_str()), SyscallSucceeds());
+
+  EXPECT_THAT(mknod(file.c_str(), S_IFREG, 0), SyscallFailsWithErrno(EEXIST));
+  EXPECT_THAT(mknod(file.c_str(), S_IFIFO, 0), SyscallFailsWithErrno(EEXIST));
+  EXPECT_THAT(mknod(slink.c_str(), S_IFREG, 0), SyscallFailsWithErrno(EEXIST));
+  EXPECT_THAT(mknod(slink.c_str(), S_IFIFO, 0), SyscallFailsWithErrno(EEXIST));
+}
+
+TEST(MknodTest, UnimplementedTypesReturnError) {
+  if (IsRunningOnGvisor()) {
+    ASSERT_THAT(mknod("/tmp/a_socket", S_IFSOCK, 0),
+                SyscallFailsWithErrno(EOPNOTSUPP));
+  }
+  // These will fail on linux as well since we don't have CAP_MKNOD.
+  ASSERT_THAT(mknod("/tmp/a_chardev", S_IFCHR, 0),
+              SyscallFailsWithErrno(EPERM));
+  ASSERT_THAT(mknod("/tmp/a_blkdev", S_IFBLK, 0), SyscallFailsWithErrno(EPERM));
+}
+
+TEST(MknodTest, Fifo) {
+  std::string const fifo = NewTempAbsPathInDir("/tmp");
+  ASSERT_THAT(mknod(fifo.c_str(), S_IFIFO | S_IRUSR | S_IWUSR, 0),
+              SyscallSucceeds());
+
+  struct stat st;
+  ASSERT_THAT(stat(fifo.c_str(), &st), SyscallSucceeds());
+  EXPECT_TRUE(S_ISFIFO(st.st_mode));
+
+  std::string msg = "some string";
+  std::vector<char> buf(512);
+
+  // Read-end of the pipe.
+  ScopedThread t([&fifo, &buf, &msg]() {
+    int fd;
+    ASSERT_THAT(fd = open(fifo.c_str(), O_RDONLY), SyscallSucceeds());
+    EXPECT_THAT(read(fd, buf.data(), buf.size()),
+                SyscallSucceedsWithValue(msg.length()));
+    EXPECT_EQ(msg, std::string(buf.data()));
+    EXPECT_THAT(close(fd), SyscallSucceeds());
+  });
+
+  // Write-end of the pipe.
+  int wfd;
+  ASSERT_THAT(wfd = open(fifo.c_str(), O_WRONLY), SyscallSucceeds());
+  EXPECT_THAT(write(wfd, msg.c_str(), msg.length()),
+              SyscallSucceedsWithValue(msg.length()));
+  EXPECT_THAT(close(wfd), SyscallSucceeds());
+}
+
+TEST(MknodTest, FifoOtrunc) {
+  std::string const fifo = NewTempAbsPathInDir("/tmp");
+  ASSERT_THAT(mknod(fifo.c_str(), S_IFIFO | S_IRUSR | S_IWUSR, 0),
+              SyscallSucceeds());
+
+  struct stat st = {};
+  ASSERT_THAT(stat(fifo.c_str(), &st), SyscallSucceeds());
+  EXPECT_TRUE(S_ISFIFO(st.st_mode));
+
+  std::string msg = "some string";
+  std::vector<char> buf(512);
+  // Read-end of the pipe.
+  ScopedThread t([&fifo, &buf, &msg]() {
+    int fd;
+    ASSERT_THAT(fd = open(fifo.c_str(), O_RDONLY), SyscallSucceeds());
+    EXPECT_THAT(read(fd, buf.data(), buf.size()),
+                SyscallSucceedsWithValue(msg.length()));
+    EXPECT_EQ(msg, std::string(buf.data()));
+    EXPECT_THAT(close(fd), SyscallSucceeds());
+  });
+
+  int wfd;
+  ASSERT_THAT(wfd = open(fifo.c_str(), O_TRUNC | O_WRONLY), SyscallSucceeds());
+  EXPECT_THAT(write(wfd, msg.c_str(), msg.length()),
+              SyscallSucceedsWithValue(msg.length()));
+  EXPECT_THAT(close(wfd), SyscallSucceeds());
+}
+
+TEST(MknodTest, FifoTruncNoOp) {
+  std::string const fifo = NewTempAbsPathInDir("/tmp");
+  ASSERT_THAT(mknod(fifo.c_str(), S_IFIFO | S_IRUSR | S_IWUSR, 0),
+              SyscallSucceeds());
+
+  EXPECT_THAT(truncate(fifo.c_str(), 0), SyscallFailsWithErrno(EINVAL));
+
+  struct stat st = {};
+  ASSERT_THAT(stat(fifo.c_str(), &st), SyscallSucceeds());
+  EXPECT_TRUE(S_ISFIFO(st.st_mode));
+
+  std::string msg = "some string";
+  std::vector<char> buf(512);
+  // Read-end of the pipe.
+  ScopedThread t([&fifo, &buf, &msg]() {
+    int rfd = 0;
+    ASSERT_THAT(rfd = open(fifo.c_str(), O_RDONLY), SyscallSucceeds());
+    EXPECT_THAT(ReadFd(rfd, buf.data(), buf.size()),
+                SyscallSucceedsWithValue(msg.length()));
+    EXPECT_EQ(msg, std::string(buf.data()));
+    EXPECT_THAT(close(rfd), SyscallSucceeds());
+  });
+
+  int wfd = 0;
+  ASSERT_THAT(wfd = open(fifo.c_str(), O_TRUNC | O_WRONLY), SyscallSucceeds());
+  EXPECT_THAT(ftruncate(wfd, 0), SyscallFailsWithErrno(EINVAL));
+  EXPECT_THAT(WriteFd(wfd, msg.c_str(), msg.length()),
+              SyscallSucceedsWithValue(msg.length()));
+  EXPECT_THAT(ftruncate(wfd, 0), SyscallFailsWithErrno(EINVAL));
+  EXPECT_THAT(close(wfd), SyscallSucceeds());
+}
+
+}  // namespace
+
+}  // namespace testing
+}  // namespace gvisor