Summary:
The ``file_time_type`` time point is used to represent the write times for files.
Its job is to act as part of a C++ wrapper for less ideal system interfaces. The
underlying filesystem uses the ``timespec`` struct for the same purpose.
However, the initial implementation of ``file_time_type`` could not represent
either the range or resolution of ``timespec``, making it unsuitable. Fixing
this requires an implementation which uses more than 64 bits to store the
time point.
I primarily considered two solutions: Using ``__int128_t`` and using a
arithmetic emulation of ``timespec``. Each has its pros and cons, and both
come with more than one complication.
However, after a lot of consideration, I decided on using `__int128_t`. This patch implements that change.
Please see the [FileTimeType Design Document](http://libcxx.llvm.org/docs/DesignDocs/FileTimeType.html) for more information.
Reviewers: mclow.lists, ldionne, joerg, arthur.j.odwyer, EricWF
Reviewed By: EricWF
Subscribers: christof, K-ballo, cfe-commits, BillyONeal
Differential Revision: https://reviews.llvm.org/D49774
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@337960 91177308-0d34-0410-b5e6-96231b3b80d8
Libc++ was incorrectly reporting an error when the target of create_directory
already exists, but was not a directory. This behavior is not specified
in the most recent standard, which says no error should be reported.
Additionally, libc++ failed to report an error when the attribute directory
path didn't exist or didn't name a directory. This has been fixed as well.
Although it's not clear if we should call status or symlink_status on the
attribute directory. This patch chooses to still call status.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@337888 91177308-0d34-0410-b5e6-96231b3b80d8
This patch implements the `what()` for filesystem errors. The message
includes the 'what_arg', any paths that were specified, and the
error code message.
Additionally this patch refactors how errors are created, making it easier
to report them correctly.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@337664 91177308-0d34-0410-b5e6-96231b3b80d8
This patch improves both the performance, and the safety of the
copy_file implementation.
The performance improvements are achieved by using sendfile on
Linux and copyfile on OS X when available.
The TOCTOU hardening is achieved by opening the source and
destination files and then using fstat to check their attributes to
see if we can copy them.
Unfortunately for the destination file, there is no way to open
it without accidentally creating it, so we first have to use
stat to determine if it exists, and if we should copy to it.
Then, once we're sure we should try to copy, we open the dest
file and ensure it names the same entity we previously stat'ed.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@337649 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch implements directory_entry caching *almost* as specified in P0317r1. However, I explicitly chose to deviate from the standard as I'll explain below.
The approach I decided to take is a fully caching one. When `refresh()` is called, the cache is populated by calls to `stat` and `lstat` as needed.
During directory iteration the cache is only populated with the `file_type` as reported by `readdir`.
The cache can be in the following states:
* `_Empty`: There is nothing in the cache (likely due to an error)
* `_IterSymlink`: Created by directory iteration when we walk onto a symlink only the symlink file type is known.
* `_IterNonSymlink`: Created by directory iteration when we walk onto a non-symlink. Both the regular file type and symlink file type are known.
* `_RefreshSymlink` and `_RefreshNonSymlink`: A full cache created by `refresh()`. This case includes dead symlinks.
* `_RefreshSymlinkUnresolved`: A partial cache created by refresh when we fail to resolve the file pointed to by a symlink (likely due to permissions). Symlink attributes are cached, but attributes about the linked entity are not.
As mentioned, this implementation purposefully deviates from the standard. According to some readings of the specification, and the Windows filesystem implementation, the constructors and modifiers which don't pass an `error_code` must throw when the `directory_entry` points to a entity which doesn't exist. or when attribute resolution fails for another reason.
@BillyONeal has proposed a more reasonable set of requirements, where modifiers other than refresh ignore errors. This is the behavior libc++ currently implements, with the expectation some form of the new language will be accepted into the standard.
Some additional semantics which differ from the Windows implementation:
1. `refresh` will not throw when the entry doesn't exist. In this case we can still meet the functions specification, so we don't treat it as an error.
2. We don't clear the path name when a constructor fails via refresh (this will hopefully be changed in the standard as well).
It should be noted that libstdc++'s current implementation has the same behavior as libc++, except for point (2).
If the changes to the specification don't get accepted, we'll be able to make the changes later.
[1] http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0317r1.html
Reviewers: mclow.lists, gromer, ldionne, aaron.ballman
Subscribers: BillyONeal, christof, cfe-commits
Differential Revision: https://reviews.llvm.org/D49530
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@337516 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The filesystem test was confused about access versus write / modification time. The spec says:
file_time_type last_write_time(const path& p, error_code& ec) noexcept;
Returns: The time of last data modification of p, determined as if by the value of the POSIX stat structure member st_mtime obtained as if by POSIX stat(). The signature with argument ec returns file_time_type::min() if an error occurs.
The test was looking at st_atime, not st_mtime, when comparing the result from last_write_time. That was probably due to using a pair instead of naming things nicely or using types. I opted to rename things so it's clearer.
This used to cause test bot failures.
<rdar://problem/40648859>
Reviewers: EricWF, mclow.lists, aemerson
Subscribers: christof, cfe-commits
Differential Revision: https://reviews.llvm.org/D47557
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@333723 91177308-0d34-0410-b5e6-96231b3b80d8
The proximate tests depended on `/net` not being a valid path,
however, on OS X it is.
Correct the tests to handle this.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@329038 91177308-0d34-0410-b5e6-96231b3b80d8
This is a fairly large patch that implements all of the filesystem NB comments
and the relative paths changes (ex. adding weakly_canonical). These issues
and papers are all interrelated so their implementation couldn't be split up
nicely.
This patch upgrades <experimental/filesystem> to match the C++17 spec and not
the published experimental TS spec. Some of the changes in this patch are both
API and ABI breaking, however libc++ makes no guarantee about stability for
experimental implementations.
The major changes in this patch are:
* Implement NB comments for filesystem (P0492R2), including:
* Implement `perm_options` enum as part of NB comments, and update the
`permissions` function to match.
* Implement changes to `remove_filename` and `replace_filename`
* Implement changes to `path::stem()` and `path::extension()` which support
splitting examples like `.profile`.
* Change path iteration to return an empty path instead of '.' for trailing
separators.
* Change `operator/=` to handle absolute paths on the RHS.
* Change `absolute` to no longer accept a current path argument.
* Implement relative paths according to NB comments (P0219r1)
* Combine `path.cpp` and `operations.cpp` since some path functions require
access to the operations internals, and some fs operations require access
to the path parser.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@329028 91177308-0d34-0410-b5e6-96231b3b80d8
The NB comments for filesystem changed permissions and added
a new enum `perm_options` which control how the permissions
are applied.
This implements than NB resolution
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@328476 91177308-0d34-0410-b5e6-96231b3b80d8
As I move towards implementing std::filesystem, there is a need to
make the existing tests run against both the std and experimental versions.
Additionally, it's helpful to allow running the tests against other
implementations of filesystem.
This patch converts the test to easily target either. First, it
adds a filesystem_include.hpp header which is soley responsible
for selecting and including the correct implementation. Second,
it converts existing tests to use this header instead of including
filesystem directly.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@328475 91177308-0d34-0410-b5e6-96231b3b80d8
APFS minimum supported file write time is -2^63 nanoseconds, which doesn't go
as far as `file_time_type::min()` that is equal to -2^63 microseconds on macOS.
This change doesn't affect filesystems that support `file_time_type` range only
for in-memory file time representation but not for on-disk representation. Such
filesystems are considered as `SupportsMinTime`.
rdar://problem/35865151
Reviewers: EricWF, Hahnfeld
Subscribers: jkorous-apple, mclow.lists, cfe-commits, christof
Differential Revision: https://reviews.llvm.org/D42755
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@326383 91177308-0d34-0410-b5e6-96231b3b80d8
This patch removes the noexcept declaration from filesystem
operations which require creating temporary paths or
creating a directory iterator. Either of these operations
can throw.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@324192 91177308-0d34-0410-b5e6-96231b3b80d8
LWG 3013 points out that the constructors and increment members
of the directory iterators need to allocate, and therefore cannot
be marked noexcept.
It also points out that `is_empty` and `copy` likely need to allocate
as well, and as such can also not be noexcept.
This patch speculatively implements the resolution removing noexcept,
because libc++ does indeed have the possibility of throwing on allocation
failure.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@316941 91177308-0d34-0410-b5e6-96231b3b80d8
I *did* try to check that such kind of an issue was not introduced
by the rL315874, but clearly i failed to finish verification.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@315876 91177308-0d34-0410-b5e6-96231b3b80d8
Previously this broke the builders, when D38101 was committed.
Silence the warning so that it can be re-landed.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@315874 91177308-0d34-0410-b5e6-96231b3b80d8
This patch speculatively implements the PR for LWG 2937, which fixes
two issues with equivalent.
(1) It makes equivalent("dne", "exists") an error. Previously only
equivalent("dne", "dne") was an error and the former case was not (it returned false).
Now equivalent reports an error when either input doesn't exist.
(2) It makes equivalent(p1, p2) well-formed when `is_other(p1) && is_other(p2)`.
Previously this was an error, but there is seemingly no reason why it should be on POSIX system.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@307117 91177308-0d34-0410-b5e6-96231b3b80d8
Filesystems are not required to maintain a hard link count consistent
with number of subdirectories. For example, on btrfs all directories
have nlink==1. Account for that in the test.
Differential Revision: https://reviews.llvm.org/D29706
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@294431 91177308-0d34-0410-b5e6-96231b3b80d8
N4100 states that an error shall be reported if
`!exists(p) || !is_directory(p)`. We were missing the first half of the
conditional. Invert the error and normal code paths to make the code
easier to follow.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@294127 91177308-0d34-0410-b5e6-96231b3b80d8
Some filesystems track atime always. This relaxes the test to accept either a
filesystem which does not accurately track atime or does track the atime
accurately. This allows the test to pass on filesystems mounted with
`strictatime` on Linux or on macOS.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@278357 91177308-0d34-0410-b5e6-96231b3b80d8
The hard link count that stat reports are different between normal hfs and the
case sensitive variant. Accept both.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@278191 91177308-0d34-0410-b5e6-96231b3b80d8
This changes how filesystem::permissions(p, perms) handles symlinks. Previously
symlinks were not resolved by default instead only getting resolved when
"perms::resolve_symlinks" was used. After this change symlinks are resolved
by default and perms::symlink_nofollow must be given to change this.
This issue has not yet been moved to Ready status, and I will revert if it
doesn't get moved at the current meeting. However I feel confident that it
will and it's nice to have implementations when moving issues.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@273328 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix passing a negative number as either tv_usec or tv_nsec. When file_time_type
is negative and has a non-zero sub-second value we subtract 1 from tv_sec
and make the sub-second duration positive.
* Detect and report when 'file_time_type' cannot be represented by time_t. This
happens when using large/small file_time_type values with a 32 bit time_t.
There is more work to be done in the implementation. It should start to use
stat's st_mtim or st_mtimeval if it's provided as an extension. That way
we can provide a better resolution.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@273103 91177308-0d34-0410-b5e6-96231b3b80d8
This patch fixes the following bugs, all of which were discovered while
testing a 32 bit build on a 64 bit machine.
* path.itr/iterator.pass.cpp has undefined behavior.
'path::iterator' stashes the value of the element inside the iterator.
This violates the BiDirIterator requirements but is allowed for path::iterator.
However this means that using reverse_iterator<path::iterator> has undefined
behavior because it assumes that 'Iter tmp = it; return *tmp' will not create
a dangling reference. However it does, and this caused this particular test
to fail.
* path.native.obs/string_alloc.pass.cpp tested the SSO with a long string.
On 32 bit builds std::wstring only has the SSO for strings of size 2. The
test was using a string of size 4.
* fs.op.space/space.pass.cpp had overflows while calculating the expected values.
The fix here is to convert the statvfs data members to std::uintmax_t before
multiplying them. The internal implementation already does this but the tests
needed to do it as well.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@273078 91177308-0d34-0410-b5e6-96231b3b80d8
Currently 4 tests are failing on the ARM buildbot. To try and diagnose each
of the failures this patch does the following:
1) path.itr/iterator.pass.cpp
* Temporarily print iteration sequence to see where its failing.
2) path.native.obs/string_alloc.pass.cpp
* Remove test that ::new is not called when constructing a short string
that requires a conversion. Since during the conversion global locale
objects might be constructed.
3) fs.op.funcs/space.pass.cpp
* Explicitly use uintmax_t in the implementation of space, hopefully
preventing possible overflows.
* Add additional tests that check for overflow is the calculation of the
space_info values.
* Add additional tests for the values returned from statfvs.
4) fs.op.funcs/last_write_time.pass.cpp
* No changes made yet.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@273075 91177308-0d34-0410-b5e6-96231b3b80d8
