The ::stat struct on Linux, FreeBSD, and OS X provides the access and
modification times as an instance of 'timespec', which has a nanosecond
resolution. The 'st_mtime' and 'st_atime' members simply reference the 'tv_sec'
value of the timespec struct. This patch changes 'last_write_time(...)' so that
it extracts both the seconds and nanoseconds values of the last modification
time, providing a more accurate implementation of 'last_write_time(...)'.
Additionally this patch fixes a possible signed integer overflow bug. The
'file_time_type' type cannot represent all possible values returned by
the filesystem. Attempting to construct a 'file_time_type' from one of these
values is undefined behavior. This patch avoids that UB by detecting possible
overflows before the conversion.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@282634 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
As pointed out by @majnemer this is a better way to detect utimensat on all
platforms. The Apple specific guard is unneeded.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@273093 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
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'.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@273034 91177308-0d34-0410-b5e6-96231b3b80d8
