* Fix a bug in split where chunking would be skipped when the chunk size
happened to be an exact divisor of the buffer size used to read the
input stream.
The issue here was that file was being split byte-wise in chunks of 1G.
The input stream was being read in chunks of 8KB, which evenly divides
the chunk size. Because the check to allocate the next output chunk was
done at the bottom of the loop previously, it would never occur because
the current input chunk was fully consumed at that point. By moving the
check to the top of the loop (but still late enough that we know we have
bytes to write) we resolve this issue.
This scenario is unfortunately hard to write a test for, since we don't
explicitly control the input chunk size.
Fixes https://github.com/uutils/coreutils/issues/3790
* test/cp: -p changes ctime and added sleep for better timestamp testing
* test/cp: add nanoseconds checking for copied timestamps
* test/cp: made compilable on other OSes
* test/cp: added error messages to assert_eq calls
* cp: Refactor `reflink`/`sparse` handling to enable `--sparse` flag
`--sparse` and `--reflink` options have a lot of similarities:
- They have similar options (`always`, `never`, `auto`)
- Both need OS specific handling
- They can be mutually exclusive
Prior to this change, `sparse` was defined as `CopyMode`, but `reflink`
wasn't. Given the similarities, it makes sense to handle them similarly.
The idea behind this change is to move all OS specific file copy
handling in the `copy_on_write_*` functions. Those function then
dispatch to the correct logic depending on the arguments (at the moment,
the tuple `(reflink, sparse)`).
Also, move the handling of `--reflink=never` from `copy_file` to the
`copy_on_write_*` functions, at the cost of a bit of code duplication,
to allow `copy_on_write_*` to handle all cases (and later handle
`--reflink=never` with `--sparse`).
* cp: Implement `--sparse` flag
This begins to address #3362
At the moment, only the `--sparse=always` logic matches the requirement
form GNU cp info page, i.e. always make holes in destination when
possible.
Sparse copy is done by copying the source to the destination block by
block (blocks being of the destination's fs block size). If the block
only holds NUL bytes, we don't write to the destination.
About `--sparse=auto`: according to GNU cp info page, the destination
file will be made sparse if the source file is sparse as well. The next
step are likely to use `lseek` with `SEEK_HOLE` detect if the source
file has holes. Currently, this has the same behaviour as
`--sparse=never`. This `SEEK_HOLE` logic can also be applied to
`--sparse=always` to improve performance when copying sparse files.
About `--sparse=never`: from my understanding, it is not guaranteed that
Rust's `fs::copy` will always produce a file with no holes, as
["platform-specific behavior may change in the
future"](https://doc.rust-lang.org/std/fs/fn.copy.html#platform-specific-behavior)
About other platforms:
- `macos`: The solution may be to use `fcntl` command `F_PUNCHHOLE`.
- `windows`: I only see `FSCTL_SET_SPARSE`.
This should pass the following GNU tests:
- `tests/cp/sparse.sh`
- `tests/cp/sparse-2.sh`
- `tests/cp/sparse-extents.sh`
- `tests/cp/sparse-extents-2.sh`
`sparse-perf.sh` needs `--sparse=auto`, and in particular a way to skip
holes in the source file.
Co-authored-by: Sylvestre Ledru <sylvestre@debian.org>
* ls: Implement --zero flag. (#2929)
This flag can be used to provide a easy machine parseable output from
ls, as discussed in the GNU bug report
https://debbugs.gnu.org/cgi/bugreport.cgi?bug=49716.
There are some peculiarities with this flag:
- Current implementation of GNU ls of the `--zero` flag implies some
other flags. Those can be overridden by setting those flags after
`--zero` in the command line.
- This flag is not compatible with `--dired`. This patch is not 100%
compliant with GNU ls: GNU ls `--zero` will fail if `--dired` and
`-l` are set, while with this patch only `--dired` is needed for the
command to fail.
We also add `--dired` flag to the parser, with no additional behaviour
change.
Testing done:
```
$ bash util/build-gnu.sh
[...]
$ bash util/run-gnu-test.sh tests/ls/zero-option.sh
[...]
PASS: tests/ls/zero-option.sh
============================================================================
Testsuite summary for GNU coreutils 9.1.36-8ec11
============================================================================
# TOTAL: 1
# PASS: 1
# SKIP: 0
# XFAIL: 0
# FAIL: 0
# XPASS: 0
# ERROR: 0
============================================================================
```
* Use the US way to spell Behavior
* Fix formatting with cargo fmt -- tests/by-util/test_ls.rs
* Simplify --zero flag overriding logic by using index_of
Also, allow multiple --zero flags, as this is possible with GNU ls
command. Only the last one is taken into account.
Co-authored-by: Sylvestre Ledru <sledru@mozilla.com>
* wc: specialize scanning loop on settings.
The primary computational loop in wc (iterating over all the
characters and computing word lengths, etc) is configured by a
number of boolean options that control the text-scanning behavior.
If we monomorphize the code loop for each possible combination of
scanning configurations, the rustc is able to generate better code
for each instantiation, at the least by removing the conditional
checks on each iteration, and possibly by allowing things like
vectorization.
On my computer (aarch64/macos), I am seeing at least a 5% performance
improvement in release builds on all wc flag configurations
(other than those that were already specialized) against
odyssey1024.txt, with wc -l showing the greatest improvement at 15%.
* Reduce the size of the wc dispatch table by half.
By extracting the handling of hand-written fast-paths to the
same dispatch as the automatic specializations, we can avoid
needing to pass `show_bytes` as a const generic to
`word_count_from_reader_specialized`. Eliminating this parameter
halves the number of arms in the dispatch.
