Commit Graph

25 Commits

Author SHA1 Message Date
Louis Dionne 87dd51983c [libc++] Remove support for CloudABI, which has been abandoned
Based on https://github.com/NuxiNL/cloudlibc, it appears that the CloudABI
project has been abandoned. This patch removes a bunch of CloudABI specific
logic that had been added to support that platform.

Note that some knobs like LIBCXX_ENABLE_STDIN and LIBCXX_ENABLE_STDOUT
coud be useful in their own right, however those are currently broken.
If we want to re-add such knobs in the future, we can do it like we've
done it for localization & friends so that we can officially support
that configuration.

Differential Revision: https://reviews.llvm.org/D108637
2021-08-24 14:11:32 -04:00
Louis Dionne a9c9183ca4 [libc++] Use the using_if_exists attribute when provided
As discussed on cfe-dev [1], use the using_if_exists Clang attribute when
the compiler supports it. This makes it easier to port libc++ on top of
new platforms that don't fully support the C Standard library.

Previously, libc++ would fail to build when trying to import a missing
declaration in a <cXXXX> header. With the attribute, the declaration will
simply not be imported into namespace std, and hence it won't be available
for libc++ to use. In many cases, the declarations were *not* actually
required for libc++ to work (they were only surfaced for users to use
them as std::XXXX), so not importing them into namespace std is acceptable.

The same thing could be achieved by conscious usage of `#ifdef` along
with platform detection, however that quickly creates a maintenance
problem as libc++ is ported to new platforms. Furthermore, this problem
is exacerbated when mixed with vendor internal-only platforms, which can
lead to difficulties maintaining a downstream fork of the library.

For the time being, we only use the using_if_exists attribute when it
is supported. At some point in the future, we will start removing #ifdef
paths that are unnecessary when the attribute is supported, and folks
who need those #ifdef paths will be required to use a compiler that
supports the attribute.

[1]: http://lists.llvm.org/pipermail/cfe-dev/2020-June/066038.html

Differential Revision: https://reviews.llvm.org/D90257
2021-06-04 09:55:21 -04:00
Louis Dionne 4cd6ca102a [libc++] NFC: Normalize `#endif //` comment indentation 2021-04-20 12:03:32 -04:00
Dan Albert 75c4408653 Reland: Don't expose unavailable cstdio functions.
Marked unsupported for C++03 and C++11 since this test uses alias
declarations, and at least one C++03 bot was failing with
-Wc++11-extensions.

Change-Id: I8c3a579edd7eb83e0bc74e85d116b68f22400161
2020-04-16 12:51:08 -07:00
Dan Albert 50280c1895 Revert "Don't expose unavailable cstdio functions."
Broke builders that emit different diagnostics. e.g.:

error: 'warning' diagnostics seen but not expected:
  Line 13: alias declarations are a C++11 extension
  Line 20: alias declarations are a C++11 extension

This reverts commit ff87813715.
2020-04-07 15:36:44 -07:00
Dan Albert ff87813715 Don't expose unavailable cstdio functions.
Summary: These aren't available on Android in all configurations.

Reviewers: EricWF, mclow.lists, #libc, ldionne

Reviewed By: EricWF, #libc, ldionne

Subscribers: broadwaylamb, dexonsmith, ldionne, krytarowski, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D76093
2020-04-07 15:02:30 -07:00
Dimitry Andric 5bd4a4806a Remove ::gets for FreeBSD 13 and later
Summary:
In https://svnweb.freebsd.org/changeset/base/351659 @emaste removed gets() from
FreeBSD 13's libc, and our copies of libc++ and libstdc++.  In that change, the
declarations were simply deleted, but I would like to propose this conditional
test instead.

Reviewers: EricWF, mclow.lists, emaste

Reviewed By: mclow.lists

Subscribers: krytarowski, christof, ldionne, emaste, libcxx-commits

Differential Revision: https://reviews.llvm.org/D67316

llvm-svn: 371324
2019-09-07 22:18:20 +00:00
Chandler Carruth 57b08b0944 Update more file headers across all of the LLVM projects in the monorepo
to reflect the new license. These used slightly different spellings that
defeated my regular expressions.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351648
2019-01-19 10:56:40 +00:00
Shoaib Meenai 17af695f2b [libc++] Drop support for CRTs older than VS 2015
LLVM dropped support for Visual Studio versions older than 2015 quite
some time ago, so I consider it safe to drop libc++'s support for older
CRTs. The CRT in Visual Studio 2015 provides a lot of previously missing
functions, so targeting it requires less special casing.

Differential Revision: https://reviews.llvm.org/D31798

llvm-svn: 299743
2017-04-07 02:20:52 +00:00
Shoaib Meenai 76728d88ec [libc++] Remove unnecessary MSVCRT exclusions
Visual Studio 2013 and up have these functions, and we don't need to
support older versions.

There are some remaining _LIBCPP_MSVCRT exclusions which are present on
Visual Studio 2015 but not 2013. Those will be addressed in a follow-up.

Differential Revision: https://reviews.llvm.org/D26377

llvm-svn: 286202
2016-11-08 03:31:42 +00:00
Saleem Abdulrasool e68b47070f cstdio: limit gets to CRT versions below 14
Microsoft removed gets from the CRT in Visual Studio 2015 onwards [1].
Attempting to reference it when targeting CRT versions 14 and above will cause
compile errors.

[1] https://msdn.microsoft.com/en-us/library/2029ea5f.aspx

Patch by Shoaib Meenai!

llvm-svn: 280417
2016-09-01 21:09:19 +00:00
Richard Smith d32827408e Split <stdio.h> out of <cstdio>.
As with <stddef.h>, skip our custom header if __need_FILE or __need___FILE is defined.

llvm-svn: 249798
2015-10-09 01:29:09 +00:00
Richard Smith 1607bb38b6 Remove unnecessary inline functions capturing the contents of C library macros.
The C standard requires that these be provided as functions even if they're
also provided as macros, and a strict reading of the C++ standard library rules
suggests that (for instance) &::isdigit == &::std::isdigit, so these wrappers
are technically non-conforming.

llvm-svn: 249475
2015-10-06 22:03:22 +00:00
Ed Schouten f4ac884f2b Make the presence of stdin and stdout optional.
The idea behind Nuxi CloudABI is that it is targeted at (but not limited to)
running networked services in a sandboxed environment. The model behind stdin,
stdout and stderr is strongly focused on interactive tools in a command shell.
CloudABI does not support the notion of stdin and stdout, as 'standard
input/output' does not apply to services. The concept of stderr does makes
sense though, as services do need some mechanism to log error messages in a
uniform way.

This patch extends libc++ in such a way that std::cin and std::cout and the
associated <cstdio>/<cwchar> functions can be disabled through the flags
_LIBCPP_HAS_NO_STDIN and _LIBCPP_HAS_NO_STDOUT, respectively. At the same time
it attempts to clean up src/iostream.cpp a bit. Instead of using a single array
of mbstate_t objects and hardcoding the array indices, it creates separate
objects that declared next to the iostream objects and their buffers. The code
is also restructured by interleaving the construction and setup of c* and wc*
objects. That way it is more obvious that this is done identically.

The c* and wc* objects already have separate unit tests. Make use of this fact
by adding XFAILs in case libcpp-has-no-std* is set. That way the tests work in
both directions. If stdin or stdout is disabled, these tests will therefore
test for the absence of c* and wc*.

Differential Revision:	http://reviews.llvm.org/D8340

llvm-svn: 233275
2015-03-26 14:35:46 +00:00
Ed Schouten 97fdea618e Add option to disable access to the global filesystem namespace.
Systems like FreeBSD's Capsicum and Nuxi CloudABI apply the concept of
capability-based security on the way processes can interact with the
filesystem API. It is no longer possible to interact with the VFS
through calls like open(), unlink(), rename(), etc. Instead, processes
are only allowed to interact with files and directories to which they
have been granted access. The *at() functions can be used for this
purpose.

This change adds a new config switch called
_LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE. If set, all functionality
that requires the global filesystem namespace will be disabled. More
concretely:

- fstream's open() function will be removed.
- cstdio will no longer pull in fopen(), rename(), etc.
- The test suite's get_temp_file_name() will be removed. This will cause
  all tests that use the global filesystem namespace to break, but will
  at least make all the other tests run (as get_temp_file_name will not
  build anyway).

It is important to mention that this change will make fstream rather
useless on those systems for now. Still, I'd rather not have fstream
disabled entirely, as it is of course possible to come up with an
extension for fstream that would allow access to local filesystem
namespaces (e.g., by adding an openat() member function).

Differential revision:	http://reviews.llvm.org/D8194
Reviewed by:		jroelofs (thanks!)

llvm-svn: 232049
2015-03-12 15:44:39 +00:00
Jonathan Roelofs cba3e4ca21 Support Newlib as libc++'s C library [cstdio part, part 2]
Wrappers for clearerr, feof, ferror (which newlib implements as macros).

http://reviews.llvm.org/D5420

llvm-svn: 225563
2015-01-10 00:08:00 +00:00
Marshall Clow 8de32cb3dc Implement national body comment GB9: remove std::gets
llvm-svn: 192538
2013-10-12 19:09:47 +00:00
Howard Hinnant 5f878d4bd2 G M: Restore the ability for libcxx to compile again on mingw 64.
llvm-svn: 190837
2013-09-17 01:34:47 +00:00
Howard Hinnant 0be8f64c44 Nico Rieck: Currently _MSC_VER and _WIN32 are used to guard code which is
MSVC-specific, MSVCRT-specific, or Windows-specific. Because Clang can
also define _MSC_VER, and MSVCRT is not necessarily the only C runtime,
these macros should not be used interchangeably.

This patch divides all Windows-related bits into the aforementioned
categories. Two new macros are introduced:

- _LIBCPP_MSVC: Defined when compiling with MSVC. Detected using
  _MSC_VER, excluding Clang.
- _LIBCPP_MSVCRT: Defined when using the Microsoft CRT. This is the default
   when _WIN32 is defined.

This leaves _WIN32 for code using the Windows API.

This also corrects the spelling of _LIBCP_HAS_IS_BASE_OF to _LIBCPP_HAS_IS_BASE_OF.

Nico, please prepare a patch for CREDITS.TXT, thanks.

llvm-svn: 187593
2013-08-01 18:17:34 +00:00
Howard Hinnant c904ad4518 Patch by Andrew C. Morrow: shims to work around macroized getc and putc on linux. On my eglibc 2.13 based Debian system 'getc' is a macro defined in
/usr/include/stdio.h. This decision to make it a macro doesn't seem to
be guarded by any feature test macro as far as I can see.

llvm-svn: 160799
2012-07-26 20:01:13 +00:00
Howard Hinnant e4383379ae More windows port work by Ruben Van Boxem
llvm-svn: 142732
2011-10-22 20:59:45 +00:00
Howard Hinnant 073458b1ab Windows support by Ruben Van Boxem.
llvm-svn: 142235
2011-10-17 20:05:10 +00:00
Howard Hinnant 412dbebe1b license change
llvm-svn: 119395
2010-11-16 22:09:02 +00:00
Howard Hinnant 5b08a8a432 Wiped out some non-ascii characters that snuck into the copyright.
llvm-svn: 103516
2010-05-11 21:36:01 +00:00
Howard Hinnant 3e519524c1 libcxx initial import
llvm-svn: 103490
2010-05-11 19:42:16 +00:00