Commit Graph

27 Commits

Author SHA1 Message Date
Eric Fiselier d491a6960a Implement P0430R2 - File system library on non-POSIX systems.
This patch implements P0430R2, who's largest change is adding the path::format
enumeration for supporting path format conversions in path constructors.

However, since libc++'s filesystem only really supports POSIX like systems,
there are no real changes needed. This patch simply adds the format enum
and then ignores it when it's passed to constructors.

llvm-svn: 329031
2018-04-02 23:35:24 +00:00
Eric Fiselier d7fae181c3 Implement filesystem NB comments, relative paths, and related issues.
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.

llvm-svn: 329028
2018-04-02 23:03:41 +00:00
Eric Fiselier 4d334c4cdd Implement filesystem::perm_options specified in NB comments.
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

llvm-svn: 328476
2018-03-26 06:23:55 +00:00
Eric Fiselier e3690ba586 Implement LWG 3014 - Fix more noexcept issues in filesystem.
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.

llvm-svn: 324192
2018-02-04 07:35:36 +00:00
Eric Fiselier be71d336bd Implement LWG2989: path's streaming operators allow everything under the sun.
Because path can be constructed from a ton of different types, including string
and wide strings, this caused it's streaming operators to suck up all sorts
of silly types via silly conversions. For example:

using namespace std::experimental::filesystem::v1;
std::wstring w(L"wide");
std::cout << w; // converts to path.

This patch tentatively adopts the resolution to LWG2989 and fixes the issue
by making the streaming operators friends of path.

llvm-svn: 324189
2018-02-04 03:10:53 +00:00
Marshall Clow 2f13e79083 More of P0600 - '[[nodiscard]] in the Library' mark empty() as nodiscard in filesystem::path
llvm-svn: 318378
2017-11-16 05:48:32 +00:00
Eric Fiselier ddfdb32b30 Implement LWG 3013 - some filesystem members should not be noexcept.
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.

llvm-svn: 316941
2017-10-30 18:59:59 +00:00
Eric Fiselier e02ed1c255 Diagnose when reverse_iterator is used on path::iterator.
path::iterator isn't a strictly conforming iterator. Specifically
it stashes the current element inside the iterator. This leads to
UB when used with reverse_iterator since it requires the element
to outlive the lifetime of the iterator.

This patch adds a static_assert inside reverse_iterator to disallow
"stashing iterator types", and it tags path::iterator as such a type.

Additionally this patch removes all uses of reverse_iterator<path::iterator>
within the tests.

llvm-svn: 300164
2017-04-13 02:54:13 +00:00
Eric Fiselier 3896bf7453 Work around recent -Wshadow changes in Clang
llvm-svn: 299407
2017-04-04 01:05:59 +00:00
Eric Fiselier bc9cbcedc1 Implement LWG 2787 - [file_status.cons] is inconsistent
llvm-svn: 297071
2017-03-06 21:02:06 +00:00
Saleem Abdulrasool e4ddaa4427 experimental: remove some extraneous _LIBCPP_FUNC_VIS
These member functions were decorated with `_LIBCPP_FUNC_VIS` when the
class is also decorated with external visibility.  This breaks down when
building for PE/COFF, where the member function cannot be decorated if
it is within a decorated class.  The class attribute will propagate to
the member.  Remove the extraneous decoration.

llvm-svn: 293454
2017-01-30 03:58:26 +00:00
Saleem Abdulrasool a902e7aa94 experimental: tolerate the existence of a `__deref` macro
Microsoft's SAL has a `__deref` macro which results in a compilation
failure when building the filesystem module on Windows.  Rename the
member function internally to avoid the conflict.

llvm-svn: 293449
2017-01-30 00:15:47 +00:00
Eric Fiselier 337a7c542d Fix filesystem::path assignment from {}
Adding `path::operator=(string_type&&)` made the expression `p = {}`
ambiguous. This path fixes that ambiguity by making the `string&&`
overload a template so it ranks lower during overload resolution.

llvm-svn: 292345
2017-01-18 05:48:55 +00:00
Eric Fiselier fd83822741 Fix unused parameters and variables
llvm-svn: 290459
2016-12-23 23:37:52 +00:00
Eric Fiselier a55333003d Optimize filesystem::path by providing weaker exception guarantees.
path uses string::append to construct, append, and concatenate paths. Unfortunatly
string::append has a strong exception safety guaranteed and if it can't prove
that the iterator operations don't throw then it will allocate a temporary
string copy to append to. However this extra allocation and copy is very
undesirable for path which doesn't have the same exception guarantees.

To work around this this patch adds string::__append_forward_unsafe which exposes
the std::string::append interface for forward iterators without enforcing
that the iterator is noexcept.

llvm-svn: 285532
2016-10-31 02:46:25 +00:00
Eric Fiselier ef915d3ef4 Improve performance of constructing filesystem::path from strings.
This patch fixes a performance bug when constructing or appending to a path
from a string or c-string. Previously we called 'push_back' to append every
single character. This caused multiple re-allocation and copies when at most
one reallocation is necessary. The new behavior is to simply call
`string::append` so it can correctly handle reallocation.

For large strings this change is a ~4x improvement. This also makes our path
faster to construct than libstdc++'s.

llvm-svn: 285530
2016-10-30 23:53:50 +00:00
Eric Fiselier 1467a197e5 Rewrite std::filesystem::path iterators and parser
This patch entirely rewrites the parsing logic for paths. Unlike the previous
implementation this one stores information about the current state; For example
if we are in a trailing separator or a root separator. This avoids the need for
extra lookahead (and extra work) when incrementing or decrementing an iterator.
Roughly this gives us a 15% speedup over the previous implementation.

Unfortunately this implementation is still a lot slower than libstdc++'s.
Because libstdc++ pre-parses and splits the path upon construction their
iterators are trivial to increment/decrement. This makes libc++ lazy parsing
100x slower than libstdc++. However the pre-parsing libstdc++ causes a ton
of extra and unneeded allocations when constructing the string. For example
`path("/foo/bar/")` would require at least 5 allocations with libstdc++
whereas libc++ uses only one. The non-allocating behavior is much preferable
when you consider filesystem usages like 'exists("/foo/bar/")'.

Even then libc++'s path seems to be twice as slow to simply construct compared
to libstdc++. More investigation is needed about this.

llvm-svn: 285526
2016-10-30 23:30:38 +00:00
Eric Fiselier 87ee8a0adb Implement modified LWG 2665
llvm-svn: 284313
2016-10-15 22:37:42 +00:00
Eric Fiselier bbcfec7edd Implement LWG2664 and update its status
llvm-svn: 284310
2016-10-15 21:29:44 +00:00
Eric Fiselier 1b17a4b7b4 Move inline attributes in filesystem to first declaration
llvm-svn: 281683
2016-09-16 00:07:16 +00:00
Eric Fiselier 49e2967f27 [libc++] Fix and document visibility attributes for Clang, GCC and Windows.
Summary:
This patch fixes a number of problems with the visibility macros across GCC (on Unix) and Windows (DLL import/export semantics). All of the visibility macros are now documented under `DesignDocs/VisibilityMacros.rst`. Now I'll no longer forget the subtleties of each!

This patch adds two new visibility macros:

* `_LIBCPP_ENUM_VIS` for controlling the typeinfo of enum types. Only Clang supports this.
* `_LIBCPP_EXTERN_TEMPLATE_TYPE_VIS` for redefining visibility on explicit instantiation declarations. Clang and Windows require this.

After applying this patch GCC only emits one -Wattribute warning opposed to 30+.


Reviewers: mclow.lists, EricWF

Subscribers: beanz, mgorny, cfe-commits

Differential Revision: https://reviews.llvm.org/D24602

llvm-svn: 281673
2016-09-15 22:27:07 +00:00
Eric Fiselier 2fc65041be Implement LWG 2711. Constrain path members.
llvm-svn: 279945
2016-08-28 21:26:01 +00:00
Marshall Clow 0fc8cec796 Followon to r279744. Find the other exception types and make __throw_XXX routines (and call them). Remove the generic __libcpp_throw routine, since no one uses it anymore.
llvm-svn: 279763
2016-08-25 17:47:09 +00:00
Eric Fiselier 0fdab5eb69 Implement P0392r0. Integrate filesystem::path and string_view.
llvm-svn: 276511
2016-07-23 03:10:56 +00:00
Eric Fiselier 44e2ebadb2 Implement LWG issue 2720. Replace perms::resolve_symlinks with perms::symlink_nofollow.
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.

llvm-svn: 273328
2016-06-21 22:42:42 +00:00
Eric Fiselier 310d3b975f Implement LWG issue 2725. The issue should move this meeting
llvm-svn: 273325
2016-06-21 22:11:16 +00:00
Eric Fiselier c79795874a Add Filesystem TS -- Complete
Add the completed std::experimental::filesystem implementation and tests.
The implementation supports C++11 or newer.

The TS is built as part of 'libc++experimental.a'. Users of the TS need to
manually link this library. Building and testing the TS can be disabled using
the CMake option '-DLIBCXX_ENABLE_FILESYSTEM=OFF'.

Currently 'libc++experimental.a' is not installed by default. To turn on the
installation of the library use '-DLIBCXX_INSTALL_EXPERIMENTAL_LIBRARY=ON'.

llvm-svn: 273034
2016-06-17 19:46:40 +00:00