+++ /dev/null
-#[cfg(target_os = "windows")]
-extern crate winapi;
-
-use std::fs;
-use std::path::PathBuf;
-use std::io::BufWriter;
-
-#[cfg(not(target_os = "windows"))]
-use std::os::unix::io::AsRawFd;
-
-use lightning::util::ser::Writeable;
-
-#[cfg(target_os = "windows")]
-use {
- std::ffi::OsStr,
- std::os::windows::ffi::OsStrExt
-};
-
-#[cfg(target_os = "windows")]
-macro_rules! call {
- ($e: expr) => (
- if $e != 0 {
- return Ok(())
- } else {
- return Err(std::io::Error::last_os_error())
- }
- )
-}
-
-#[cfg(target_os = "windows")]
-fn path_to_windows_str<T: AsRef<OsStr>>(path: T) -> Vec<winapi::shared::ntdef::WCHAR> {
- path.as_ref().encode_wide().chain(Some(0)).collect()
-}
-
-#[allow(bare_trait_objects)]
-pub(crate) fn write_to_file<W: Writeable>(dest_file: PathBuf, data: &W) -> std::io::Result<()> {
- let mut tmp_file = dest_file.clone();
- tmp_file.set_extension("tmp");
-
- let parent_directory = dest_file.parent().unwrap();
- fs::create_dir_all(parent_directory)?;
- // Do a crazy dance with lots of fsync()s to be overly cautious here...
- // We never want to end up in a state where we've lost the old data, or end up using the
- // old data on power loss after we've returned.
- // The way to atomically write a file on Unix platforms is:
- // open(tmpname), write(tmpfile), fsync(tmpfile), close(tmpfile), rename(), fsync(dir)
- {
- // Note that going by rust-lang/rust@d602a6b, on MacOS it is only safe to use
- // rust stdlib 1.36 or higher.
- let mut buf = BufWriter::new(fs::File::create(&tmp_file)?);
- data.write(&mut buf)?;
- buf.into_inner()?.sync_all()?;
- }
- // Fsync the parent directory on Unix.
- #[cfg(not(target_os = "windows"))]
- {
- fs::rename(&tmp_file, &dest_file)?;
- let dir_file = fs::OpenOptions::new().read(true).open(parent_directory)?;
- unsafe { libc::fsync(dir_file.as_raw_fd()); }
- }
- #[cfg(target_os = "windows")]
- {
- if dest_file.exists() {
- unsafe {winapi::um::winbase::ReplaceFileW(
- path_to_windows_str(dest_file).as_ptr(), path_to_windows_str(tmp_file).as_ptr(), std::ptr::null(),
- winapi::um::winbase::REPLACEFILE_IGNORE_MERGE_ERRORS,
- std::ptr::null_mut() as *mut winapi::ctypes::c_void,
- std::ptr::null_mut() as *mut winapi::ctypes::c_void
- )};
- } else {
- call!(unsafe {winapi::um::winbase::MoveFileExW(
- path_to_windows_str(tmp_file).as_ptr(), path_to_windows_str(dest_file).as_ptr(),
- winapi::um::winbase::MOVEFILE_WRITE_THROUGH | winapi::um::winbase::MOVEFILE_REPLACE_EXISTING
- )});
- }
- }
- Ok(())
-}
-
-#[cfg(test)]
-mod tests {
- use lightning::util::ser::{Writer, Writeable};
-
- use super::{write_to_file};
- use std::fs;
- use std::io;
- use std::path::PathBuf;
-
- struct TestWriteable{}
- impl Writeable for TestWriteable {
- fn write<W: Writer>(&self, writer: &mut W) -> Result<(), std::io::Error> {
- writer.write_all(&[42; 1])
- }
- }
-
- // Test that if the persister's path to channel data is read-only, writing
- // data to it fails. Windows ignores the read-only flag for folders, so this
- // test is Unix-only.
- #[cfg(not(target_os = "windows"))]
- #[test]
- fn test_readonly_dir() {
- let test_writeable = TestWriteable{};
- let filename = "test_readonly_dir_persister_filename".to_string();
- let path = "test_readonly_dir_persister_dir";
- fs::create_dir_all(path).unwrap();
- let mut perms = fs::metadata(path).unwrap().permissions();
- perms.set_readonly(true);
- fs::set_permissions(path, perms).unwrap();
- let mut dest_file = PathBuf::from(path);
- dest_file.push(filename);
- match write_to_file(dest_file, &test_writeable) {
- Err(e) => assert_eq!(e.kind(), io::ErrorKind::PermissionDenied),
- _ => panic!("Unexpected error message")
- }
- }
-
- // Test failure to rename in the process of atomically creating a channel
- // monitor's file. We induce this failure by making the `tmp` file a
- // directory.
- // Explanation: given "from" = the file being renamed, "to" = the destination
- // file that already exists: Unix should fail because if "from" is a file,
- // then "to" is also required to be a file.
- // TODO: ideally try to make this work on Windows again
- #[cfg(not(target_os = "windows"))]
- #[test]
- fn test_rename_failure() {
- let test_writeable = TestWriteable{};
- let filename = "test_rename_failure_filename";
- let path = "test_rename_failure_dir";
- let mut dest_file = PathBuf::from(path);
- dest_file.push(filename);
- // Create the channel data file and make it a directory.
- fs::create_dir_all(dest_file.clone()).unwrap();
- match write_to_file(dest_file, &test_writeable) {
- Err(e) => assert_eq!(e.raw_os_error(), Some(libc::EISDIR)),
- _ => panic!("Unexpected Ok(())")
- }
- fs::remove_dir_all(path).unwrap();
- }
-
- #[test]
- fn test_diskwriteable_failure() {
- struct FailingWriteable {}
- impl Writeable for FailingWriteable {
- fn write<W: Writer>(&self, _writer: &mut W) -> Result<(), std::io::Error> {
- Err(std::io::Error::new(std::io::ErrorKind::Other, "expected failure"))
- }
- }
-
- let filename = "test_diskwriteable_failure";
- let path = "test_diskwriteable_failure_dir";
- let test_writeable = FailingWriteable{};
- let mut dest_file = PathBuf::from(path);
- dest_file.push(filename);
- match write_to_file(dest_file, &test_writeable) {
- Err(e) => {
- assert_eq!(e.kind(), std::io::ErrorKind::Other);
- assert_eq!(e.get_ref().unwrap().to_string(), "expected failure");
- },
- _ => panic!("unexpected result")
- }
- fs::remove_dir_all(path).unwrap();
- }
-
- // Test failure to create the temporary file in the persistence process.
- // We induce this failure by having the temp file already exist and be a
- // directory.
- #[test]
- fn test_tmp_file_creation_failure() {
- let test_writeable = TestWriteable{};
- let filename = "test_tmp_file_creation_failure_filename".to_string();
- let path = "test_tmp_file_creation_failure_dir";
- let mut dest_file = PathBuf::from(path);
- dest_file.push(filename);
- let mut tmp_file = dest_file.clone();
- tmp_file.set_extension("tmp");
- fs::create_dir_all(tmp_file).unwrap();
- match write_to_file(dest_file, &test_writeable) {
- Err(e) => {
- #[cfg(not(target_os = "windows"))]
- assert_eq!(e.raw_os_error(), Some(libc::EISDIR));
- #[cfg(target_os = "windows")]
- assert_eq!(e.kind(), io::ErrorKind::PermissionDenied);
- }
- _ => panic!("Unexpected error message")
- }
- }
-}
projects / rust-lightning / blobdiff