libcryfs/test/fspp/fuse/closeFile/FuseCloseTest.cpp
Sebastian Messmer 449133e3da - Allow callback when fuse filesystem is mounted
- Use that callback to initialize the file system instead of initializing it up front
2018-12-03 01:57:30 -05:00

97 lines
3.1 KiB
C++

#include "../../testutils/FuseTest.h"
#include "../../testutils/OpenFileHandle.h"
#include <condition_variable>
using ::testing::WithParamInterface;
using ::testing::Values;
using std::string;
using std::mutex;
using std::unique_lock;
using std::condition_variable;
using std::chrono::duration;
using std::chrono::seconds;
using cpputils::unique_ref;
using cpputils::make_unique_ref;
// The fuse behaviour is: For each open(), there will be exactly one call to release().
// Directly before this call to release(), flush() will be called. After flush() returns,
// the ::close() syscall (in the process using the filesystem) returns. So the fuse release() call is
// called asynchronously afterwards. Errors have to be returned in the implementation of flush().
// Citing FUSE spec:
// 1) Flush is called on each close() of a file descriptor.
// 2) Filesystems shouldn't assume that flush will always be called after some writes, or that if will be called at all.
// I can't get these sentences together. For the test cases here, I go with the first one and assume that
// flush() will ALWAYS be called on a file close.
class Barrier {
public:
Barrier(): m(), cv(), finished(false) {}
template<class A, class B>
void WaitAtMost(const duration<A, B> &atMost) {
unique_lock<mutex> lock(m);
if (!finished) {
cv.wait_for(lock, atMost, [this] () {return finished;});
}
}
void Release() {
unique_lock<mutex> lock(m);
finished = true;
cv.notify_all();
}
private:
mutex m;
condition_variable cv;
bool finished;
};
class FuseCloseTest: public FuseTest, public WithParamInterface<int> {
public:
const string FILENAME = "/myfile";
void OpenAndCloseFile(const string &filename) {
auto fs = TestFS();
auto fd = OpenFile(fs.get(), filename);
CloseFile(std::move(fd));
}
unique_ref<OpenFileHandle> OpenFile(const TempTestFS *fs, const string &filename) {
auto real_path = fs->mountDir() / filename;
auto fd = make_unique_ref<OpenFileHandle>(real_path.string().c_str(), O_RDONLY);
EXPECT_GE(fd->fd(), 0) << "Opening file failed";
return fd;
}
void CloseFile(unique_ref<OpenFileHandle> fd) {
int retval = ::close(fd->fd());
EXPECT_EQ(0, retval);
fd->release(); // don't try closing it again
}
};
INSTANTIATE_TEST_CASE_P(FuseCloseTest, FuseCloseTest, Values(0, 1, 2, 100, 1024*1024*1024));
//TODO Figure out what's wrong and enable this test
//Disabled, because it is flaky. libfuse seems to not send the release() event sometimes.
/*TEST_P(FuseCloseTest, CloseFile) {
Barrier barrier;
ReturnIsFileOnLstat(FILENAME);
EXPECT_CALL(*fsimpl, openFile(StrEq(FILENAME), _)).WillOnce(Return(GetParam()));
{
//InSequence fileCloseSequence;
EXPECT_CALL(*fsimpl, flush(Eq(GetParam()))).Times(1);
EXPECT_CALL(*fsimpl, closeFile(Eq(GetParam()))).Times(1).WillOnce(Invoke([&barrier] (int) {
// Release the waiting lock at the end of this test case, because the fuse release() came in now.
barrier.Release();
}));
}
OpenAndCloseFile(FILENAME);
// Wait, until fuse release() was called, so we can check for the function call expectation.
barrier.WaitAtMost(seconds(10));
}*/