[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

Author: ldionne

libcxx/CMakeLists.txt

@@ -263,11 +263,7 @@ set(LIBCXX_GCC_TOOLCHAIN "" CACHE STRING "Use alternate GCC toolchain.")
 # Feature options -------------------------------------------------------------
 option(LIBCXX_ENABLE_EXCEPTIONS "Use exceptions." ON)
 option(LIBCXX_ENABLE_RTTI "Use run time type information." ON)
-option(LIBCXX_ENABLE_GLOBAL_FILESYSTEM_NAMESPACE "Build libc++ with support for the global filesystem namespace." ON)
-option(LIBCXX_ENABLE_STDIN "Build libc++ with support for stdin/std::cin." ON)
-option(LIBCXX_ENABLE_STDOUT "Build libc++ with support for stdout/std::cout." ON)
 option(LIBCXX_ENABLE_THREADS "Build libc++ with support for threads." ON)
-option(LIBCXX_ENABLE_THREAD_UNSAFE_C_FUNCTIONS "Build libc++ with support for thread-unsafe C functions" ON)
 option(LIBCXX_ENABLE_MONOTONIC_CLOCK
   "Build libc++ with support for a monotonic clock.
    This option may only be set to OFF when LIBCXX_ENABLE_THREADS=OFF." ON)
@@ -868,12 +864,8 @@ config_define_if(LIBCXX_ABI_UNSTABLE _LIBCPP_ABI_UNSTABLE)
 config_define_if(LIBCXX_ABI_FORCE_ITANIUM _LIBCPP_ABI_FORCE_ITANIUM)
 config_define_if(LIBCXX_ABI_FORCE_MICROSOFT _LIBCPP_ABI_FORCE_MICROSOFT)
 config_define_if(LIBCXX_HIDE_FROM_ABI_PER_TU_BY_DEFAULT _LIBCPP_HIDE_FROM_ABI_PER_TU_BY_DEFAULT)
-config_define_if_not(LIBCXX_ENABLE_GLOBAL_FILESYSTEM_NAMESPACE _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE)
-config_define_if_not(LIBCXX_ENABLE_STDIN _LIBCPP_HAS_NO_STDIN)
-config_define_if_not(LIBCXX_ENABLE_STDOUT _LIBCPP_HAS_NO_STDOUT)
 config_define_if_not(LIBCXX_ENABLE_THREADS _LIBCPP_HAS_NO_THREADS)
 config_define_if_not(LIBCXX_ENABLE_MONOTONIC_CLOCK _LIBCPP_HAS_NO_MONOTONIC_CLOCK)
-config_define_if_not(LIBCXX_ENABLE_THREAD_UNSAFE_C_FUNCTIONS _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS)
 if (NOT LIBCXX_TYPEINFO_COMPARISON_IMPLEMENTATION STREQUAL "default")
   config_define("${LIBCXX_TYPEINFO_COMPARISON_IMPLEMENTATION}" _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION)
 endif()

libcxx/docs/DesignDocs/CapturingConfigInfo.rst

@@ -65,12 +65,8 @@ configuration all together. An example "__config" header generated when
   #ifndef _LIBCPP_CONFIG_SITE
   #define _LIBCPP_CONFIG_SITE
 
-  /* #undef _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE */
-  /* #undef _LIBCPP_HAS_NO_STDIN */
-  /* #undef _LIBCPP_HAS_NO_STDOUT */
   #define _LIBCPP_HAS_NO_THREADS
   /* #undef _LIBCPP_HAS_NO_MONOTONIC_CLOCK */
-  /* #undef _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS */
 
   #endif
   // -*- C++ -*-

libcxx/include/__config

@@ -318,7 +318,7 @@
 #  endif
 #endif // __sun__
 
-#if defined(__OpenBSD__) || defined(__CloudABI__)
+#if defined(__OpenBSD__)
    // Certain architectures provide arc4random(). Prefer using
    // arc4random() over /dev/{u,}random to make it possible to obtain
    // random data even when using sandboxing mechanisms such as chroots,
@@ -935,7 +935,7 @@ typedef unsigned int   char32_t;
 #endif
 
 #if defined(__APPLE__) || defined(__FreeBSD__) || defined(_LIBCPP_MSVCRT_LIKE) || \
-    defined(__sun__) || defined(__NetBSD__) || defined(__CloudABI__)
+    defined(__sun__) || defined(__NetBSD__)
 #define _LIBCPP_LOCALE__L_EXTENSIONS 1
 #endif
 
@@ -1139,7 +1139,6 @@ extern "C" _LIBCPP_FUNC_VIS void __sanitizer_annotate_contiguous_container(
       defined(__linux__) || \
       defined(__GNU__) || \
       defined(__APPLE__) || \
-      defined(__CloudABI__) || \
       defined(__sun__) || \
       defined(__MVS__) || \
       defined(_AIX) || \
@@ -1213,40 +1212,19 @@ extern "C" _LIBCPP_FUNC_VIS void __sanitizer_annotate_contiguous_container(
 # define _LIBCPP_HAS_TRIVIAL_CONDVAR_DESTRUCTION
 #endif
 
-// Systems that use capability-based security (FreeBSD with Capsicum,
-// Nuxi CloudABI) may only provide local filesystem access (using *at()).
-// Functions like open(), rename(), unlink() and stat() should not be
-// used, as they attempt to access the global filesystem namespace.
-#ifdef __CloudABI__
-#define _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE
-#endif
-
-// CloudABI is intended for running networked services. Processes do not
-// have standard input and output channels.
-#ifdef __CloudABI__
-#define _LIBCPP_HAS_NO_STDIN
-#define _LIBCPP_HAS_NO_STDOUT
-#endif
-
 // Some systems do not provide gets() in their C library, for security reasons.
 #if defined(_LIBCPP_MSVCRT) || \
     (defined(__FreeBSD_version) && __FreeBSD_version >= 1300043) || \
     defined(__OpenBSD__)
 #   define _LIBCPP_C_HAS_NO_GETS
 #endif
 
-#if defined(__BIONIC__) || defined(__CloudABI__) || defined(__NuttX__) ||      \
+#if defined(__BIONIC__) || defined(__NuttX__) ||      \
     defined(__Fuchsia__) || defined(__wasi__) || defined(_LIBCPP_HAS_MUSL_LIBC) || \
     defined(__MVS__) || defined(__OpenBSD__)
 #define _LIBCPP_PROVIDES_DEFAULT_RUNE_TABLE
 #endif
 
-// Thread-unsafe functions such as strtok() and localtime()
-// are not available.
-#ifdef __CloudABI__
-#define _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
-#endif
-
 #if __has_feature(cxx_atomic) || __has_extension(c_atomic) || __has_keyword(_Atomic)
 #  define _LIBCPP_HAS_C_ATOMIC_IMP
 #elif defined(_LIBCPP_COMPILER_GCC)

libcxx/include/__config_site.in

@@ -14,12 +14,8 @@
 #cmakedefine _LIBCPP_ABI_FORCE_ITANIUM
 #cmakedefine _LIBCPP_ABI_FORCE_MICROSOFT
 #cmakedefine _LIBCPP_HIDE_FROM_ABI_PER_TU_BY_DEFAULT
-#cmakedefine _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE
-#cmakedefine _LIBCPP_HAS_NO_STDIN
-#cmakedefine _LIBCPP_HAS_NO_STDOUT
 #cmakedefine _LIBCPP_HAS_NO_THREADS
 #cmakedefine _LIBCPP_HAS_NO_MONOTONIC_CLOCK
-#cmakedefine _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
 #cmakedefine _LIBCPP_HAS_MUSL_LIBC
 #cmakedefine _LIBCPP_HAS_THREAD_API_PTHREAD
 #cmakedefine _LIBCPP_HAS_THREAD_API_EXTERNAL

libcxx/include/clocale

@@ -44,9 +44,7 @@ lconv* localeconv();
 _LIBCPP_BEGIN_NAMESPACE_STD
 
 using ::lconv _LIBCPP_USING_IF_EXISTS;
-#ifndef _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
 using ::setlocale _LIBCPP_USING_IF_EXISTS;
-#endif
 using ::localeconv _LIBCPP_USING_IF_EXISTS;
 
 _LIBCPP_END_NAMESPACE_STD

libcxx/include/cstdio

@@ -145,30 +145,24 @@ using ::feof _LIBCPP_USING_IF_EXISTS;
 using ::ferror _LIBCPP_USING_IF_EXISTS;
 using ::perror _LIBCPP_USING_IF_EXISTS;
 
-#ifndef _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE
 using ::fopen _LIBCPP_USING_IF_EXISTS;
 using ::freopen _LIBCPP_USING_IF_EXISTS;
 using ::remove _LIBCPP_USING_IF_EXISTS;
 using ::rename _LIBCPP_USING_IF_EXISTS;
 using ::tmpfile _LIBCPP_USING_IF_EXISTS;
 using ::tmpnam _LIBCPP_USING_IF_EXISTS;
-#endif
 
-#ifndef _LIBCPP_HAS_NO_STDIN
 using ::getchar _LIBCPP_USING_IF_EXISTS;
 #if _LIBCPP_STD_VER <= 11 && !defined(_LIBCPP_C_HAS_NO_GETS)
 using ::gets _LIBCPP_USING_IF_EXISTS;
 #endif
 using ::scanf _LIBCPP_USING_IF_EXISTS;
 using ::vscanf _LIBCPP_USING_IF_EXISTS;
-#endif
 
-#ifndef _LIBCPP_HAS_NO_STDOUT
 using ::printf _LIBCPP_USING_IF_EXISTS;
 using ::putchar _LIBCPP_USING_IF_EXISTS;
 using ::puts _LIBCPP_USING_IF_EXISTS;
 using ::vprintf _LIBCPP_USING_IF_EXISTS;
-#endif
 
 _LIBCPP_END_NAMESPACE_STD
 

libcxx/include/cstring

@@ -84,9 +84,7 @@ using ::strpbrk _LIBCPP_USING_IF_EXISTS;
 using ::strrchr _LIBCPP_USING_IF_EXISTS;
 using ::strspn _LIBCPP_USING_IF_EXISTS;
 using ::strstr _LIBCPP_USING_IF_EXISTS;
-#ifndef _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
 using ::strtok _LIBCPP_USING_IF_EXISTS;
-#endif
 using ::memset _LIBCPP_USING_IF_EXISTS;
 using ::strerror _LIBCPP_USING_IF_EXISTS;
 using ::strlen _LIBCPP_USING_IF_EXISTS;

libcxx/include/ctime

@@ -79,12 +79,10 @@ using ::clock _LIBCPP_USING_IF_EXISTS;
 using ::difftime _LIBCPP_USING_IF_EXISTS;
 using ::mktime _LIBCPP_USING_IF_EXISTS;
 using ::time _LIBCPP_USING_IF_EXISTS;
-#ifndef _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
 using ::asctime _LIBCPP_USING_IF_EXISTS;
 using ::ctime _LIBCPP_USING_IF_EXISTS;
 using ::gmtime _LIBCPP_USING_IF_EXISTS;
 using ::localtime _LIBCPP_USING_IF_EXISTS;
-#endif
 using ::strftime _LIBCPP_USING_IF_EXISTS;
 #if _LIBCPP_STD_VER > 14 && defined(_LIBCPP_HAS_TIMESPEC_GET) && !defined(_LIBCPP_HAS_TIMESPEC_GET_NOT_ACTUALLY_PROVIDED)
 using ::timespec_get _LIBCPP_USING_IF_EXISTS;

libcxx/include/cwchar

@@ -175,17 +175,13 @@ using ::wcrtomb _LIBCPP_USING_IF_EXISTS;
 using ::mbsrtowcs _LIBCPP_USING_IF_EXISTS;
 using ::wcsrtombs _LIBCPP_USING_IF_EXISTS;
 
-#ifndef _LIBCPP_HAS_NO_STDIN
 using ::getwchar _LIBCPP_USING_IF_EXISTS;
 using ::vwscanf _LIBCPP_USING_IF_EXISTS;
 using ::wscanf _LIBCPP_USING_IF_EXISTS;
-#endif
 
-#ifndef _LIBCPP_HAS_NO_STDOUT
 using ::putwchar _LIBCPP_USING_IF_EXISTS;
 using ::vwprintf _LIBCPP_USING_IF_EXISTS;
 using ::wprintf _LIBCPP_USING_IF_EXISTS;
-#endif
 
 _LIBCPP_END_NAMESPACE_STD