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macro_rules! file_ext {
($file:ty, $file_name:literal) => {
use std::io::Result;
impl $crate::sealed::Sealed for $file {}
impl $crate::FileExt for $file {
#[cfg_attr(not(tarpaulin), inline(always))]
fn allocated_size(&self) -> Result<u64> {
sys::allocated_size(self)
}
#[cfg_attr(not(tarpaulin), inline(always))]
fn allocate(&self, len: u64) -> Result<()> {
sys::allocate(self, len)
}
#[cfg_attr(not(tarpaulin), inline(always))]
fn lock_shared(&self) -> Result<()> {
sys::lock_shared(self)
}
#[cfg_attr(not(tarpaulin), inline(always))]
fn lock(&self) -> Result<()> {
sys::lock(self)
}
#[cfg_attr(not(tarpaulin), inline(always))]
fn try_lock_shared(&self) -> std::result::Result<(), $crate::TryLockError> {
sys::try_lock_shared(self)
}
#[cfg_attr(not(tarpaulin), inline(always))]
fn try_lock(&self) -> std::result::Result<(), $crate::TryLockError> {
sys::try_lock(self)
}
#[cfg_attr(not(tarpaulin), inline(always))]
fn unlock(&self) -> Result<()> {
sys::unlock(self)
}
}
};
}
macro_rules! test_mod {
($($use_stmt:item)*) => {
#[cfg(test)]
mod test {
extern crate tempfile;
use crate::{allocation_granularity, statvfs, FsStats, TryLockError, FileExt};
$(
$use_stmt
)*
/// Exercises `impl<F: FileExt + ?Sized> FileExt for &F`. Without this
/// every method body in the blanket impl is uncovered, since the
/// other tests call methods directly on the concrete file type and
/// resolve to `<File as FileExt>::*`.
#[test]
fn file_ext_blanket_for_ref() {
fn drive<F: FileExt + ?Sized>(f: &F, len: u64) {
f.lock_shared().unwrap();
f.unlock().unwrap();
f.lock().unwrap();
f.unlock().unwrap();
f.try_lock_shared().unwrap();
f.unlock().unwrap();
f.try_lock().unwrap();
f.unlock().unwrap();
f.allocate(len).unwrap();
let _ = f.allocated_size().unwrap();
}
let tempdir = tempfile::TempDir::with_prefix("fs4").unwrap();
let path = tempdir.path().join("fs4");
let file = fs::OpenOptions::new()
.read(true)
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap();
let blksize = allocation_granularity(&path).unwrap();
// `&&file` makes the inner `F` bind to `&File`, so all method
// calls resolve to the `<&File as FileExt>` blanket impl.
drive(&&file, blksize);
}
/// Tests shared file lock operations.
#[test]
fn lock_shared() {
let tempdir = tempfile::TempDir::with_prefix("fs4").unwrap();
let path = tempdir.path().join("fs4");
let file1 = fs::OpenOptions::new()
.read(true)
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap();
let file2 = fs::OpenOptions::new()
.read(true)
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap();
let file3 = fs::OpenOptions::new()
.read(true)
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap();
// Concurrent shared access is OK, but not shared and exclusive.
FileExt::lock_shared(&file1).unwrap();
FileExt::lock_shared(&file2).unwrap();
assert!(matches!(
FileExt::try_lock(&file3),
Err(TryLockError::WouldBlock),
));
FileExt::unlock(&file1).unwrap();
assert!(matches!(
FileExt::try_lock(&file3),
Err(TryLockError::WouldBlock),
));
// Once all shared file locks are dropped, an exclusive lock may be created;
FileExt::unlock(&file2).unwrap();
FileExt::lock(&file3).unwrap();
}
/// Tests exclusive file lock operations.
#[test]
fn lock_exclusive() {
let tempdir = tempfile::TempDir::with_prefix("fs4").unwrap();
let path = tempdir.path().join("fs4");
let file1 = fs::OpenOptions::new()
.read(true)
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap();
let file2 = fs::OpenOptions::new()
.read(true)
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap();
// No other access is possible once an exclusive lock is created.
FileExt::lock(&file1).unwrap();
assert!(matches!(
FileExt::try_lock(&file2),
Err(TryLockError::WouldBlock),
));
assert!(matches!(
FileExt::try_lock_shared(&file2),
Err(TryLockError::WouldBlock),
));
// Once the exclusive lock is dropped, the second file is able to create a lock.
FileExt::unlock(&file1).unwrap();
FileExt::lock(&file2).unwrap();
}
/// Tests that a lock is released after the file that owns it is dropped.
#[test]
fn lock_cleanup() {
let tempdir = tempfile::TempDir::with_prefix("fs4").unwrap();
let path = tempdir.path().join("fs4");
let file1 = fs::OpenOptions::new()
.read(true)
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap();
let file2 = fs::OpenOptions::new()
.read(true)
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap();
FileExt::lock(&file1).unwrap();
assert!(matches!(
FileExt::try_lock_shared(&file2),
Err(TryLockError::WouldBlock),
));
// Drop file1; the lock should be released.
drop(file1);
FileExt::lock_shared(&file2).unwrap();
}
/// Tests file allocation.
#[test]
fn allocate() {
let tempdir = tempfile::TempDir::with_prefix("fs4").unwrap();
let path = tempdir.path().join("fs4");
let file = fs::OpenOptions::new()
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap();
let blksize = allocation_granularity(&path).unwrap();
// New files are created with no allocated size.
assert_eq!(0, FileExt::allocated_size(&file).unwrap());
assert_eq!(0, file.metadata().unwrap().len());
// Allocate space for the file, checking that the allocated size steps
// up by block size, and the file length matches the allocated size.
FileExt::allocate(&file, 2 * blksize - 1).unwrap();
assert_eq!(2 * blksize, FileExt::allocated_size(&file).unwrap());
assert_eq!(2 * blksize - 1, file.metadata().unwrap().len());
// Truncate the file, checking that the allocated size steps down by
// block size.
file.set_len(blksize + 1).unwrap();
assert_eq!(2 * blksize, FileExt::allocated_size(&file).unwrap());
assert_eq!(blksize + 1, file.metadata().unwrap().len());
}
/// Regression for issue #13: on Windows, re-`allocate`-ing inside
/// an already-allocated cluster must not move the EOF pointer
/// (the old behaviour called `set_len`, which triggered Windows
/// buffered-I/O quirks). The trait doc explicitly carves this
/// behaviour out from the general "file size is at least `len`"
/// contract, so this test asserts the strict invariant on
/// Windows and a loose one on Unix.
#[test]
fn allocate_preserves_eof_within_cluster() {
let tempdir = tempfile::TempDir::with_prefix("fs4").unwrap();
let path = tempdir.path().join("fs4");
let file = fs::OpenOptions::new()
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap();
let blksize = allocation_granularity(&path).unwrap();
// Reserve cluster-aligned space but leave EOF below the
// cluster boundary — the precondition reported in #13.
FileExt::allocate(&file, 2 * blksize - 1).unwrap();
assert_eq!(2 * blksize - 1, file.metadata().unwrap().len());
// Request `allocate` up to the cluster boundary. Before
// the fix, Windows would `set_len(2*blksize)`; after, it
// short-circuits since `allocated_size >= len`.
FileExt::allocate(&file, 2 * blksize).unwrap();
#[cfg(windows)]
assert_eq!(
2 * blksize - 1,
file.metadata().unwrap().len(),
"Windows allocate must not extend EOF inside an already-allocated cluster (#13)",
);
#[cfg(unix)]
assert!(file.metadata().unwrap().len() >= 2 * blksize - 1);
}
/// Regression: `allocate` on a sparse file must reserve
/// blocks even when logical EOF already covers `len`. The
/// previous Unix implementation short-circuited on
/// `metadata().len()`, which for a file extended via
/// `set_len` is true with zero blocks allocated, so the
/// documented preallocation contract silently became a
/// no-op. Gated to Linux where `set_len` reliably
/// produces a sparse file and `st_blocks` reliably
/// reflects `fallocate` reservations.
#[cfg(target_os = "linux")]
#[test]
fn allocate_reserves_blocks_on_sparse_file() {
let tempdir = tempfile::TempDir::with_prefix("fs4").unwrap();
let path = tempdir.path().join("fs4");
let file = fs::OpenOptions::new()
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap();
let blksize = allocation_granularity(&path).unwrap();
// `set_len` extends logical EOF without reserving blocks:
// the file is sparse with `len = 4 * blksize` and
// `allocated_size = 0`.
file.set_len(4 * blksize).unwrap();
assert_eq!(4 * blksize, file.metadata().unwrap().len());
assert_eq!(0, FileExt::allocated_size(&file).unwrap());
FileExt::allocate(&file, 4 * blksize).unwrap();
assert!(
FileExt::allocated_size(&file).unwrap() >= 4 * blksize,
"allocate on a sparse file must reserve blocks",
);
}
/// Exercises the `Err` arm of the Unix `fallocate` call by
/// invoking `allocate` on a read-only file descriptor,
/// which returns `EBADF`. Without this test the error
/// conversion (`std::io::Error::from_raw_os_error`) and
/// the `Err(...) => Err(...)` match arm are uncovered.
/// Gated to Unix: Windows has a separate `allocate` with
/// its own error path.
#[cfg(unix)]
#[test]
fn allocate_forwards_fallocate_error() {
let tempdir = tempfile::TempDir::with_prefix("fs4").unwrap();
let path = tempdir.path().join("fs4");
// Create then close the file so it exists on disk.
drop(
fs::OpenOptions::new()
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap(),
);
// Re-open read-only. `fallocate` requires the fd to
// be writable, so the syscall fails with EBADF and
// the error is propagated through the match arm.
let file = fs::OpenOptions::new().read(true).open(&path).unwrap();
let err = FileExt::allocate(&file, 4096).unwrap_err();
assert!(
err.raw_os_error().is_some(),
"expected a raw OS error from fallocate, got {err:?}",
);
}
/// Re-allocating the same length must not fail. Regression for issue #15.
#[test]
fn allocate_idempotent() {
let tempdir = tempfile::TempDir::with_prefix("fs4").unwrap();
let path = tempdir.path().join("fs4");
let file = fs::OpenOptions::new()
.write(true)
.create(true)
.truncate(true)
.open(&path)
.unwrap();
let blksize = allocation_granularity(&path).unwrap();
FileExt::allocate(&file, 2 * blksize).unwrap();
FileExt::allocate(&file, 2 * blksize).unwrap();
FileExt::allocate(&file, blksize).unwrap();
assert!(file.metadata().unwrap().len() >= 2 * blksize);
}
/// Checks filesystem space methods.
///
/// Does not assert `available_space <= free_space`: on
/// macOS APFS the kernel reports `f_bavail > f_bfree`
/// because purgeable space (snapshots, cached data) is
/// counted as available but not as free, so the usual
/// POSIX invariant does not hold.
#[test]
fn filesystem_space() {
let tempdir = tempfile::TempDir::with_prefix("fs4").unwrap();
let FsStats {
free_space,
available_space,
total_space,
..
} = statvfs(tempdir.path()).unwrap();
assert!(total_space >= free_space);
assert!(total_space >= available_space);
}
}
};
}
cfg_sync! {
pub(crate) mod std_impl;
}
cfg_fs_err2! {
pub(crate) mod fs_err2_impl;
}
cfg_fs_err3! {
pub(crate) mod fs_err3_impl;
}