[libc++][print] Moves is_terminal to the dylib. (#80464)

Having the test in the header requires including unistd.h on POSIX
platforms. This header has other declarations which may conflict with
code that uses named declarations provided by this header. For example
code using "int pipe;" would conflict with the function pipe in this
header.

Moving the code to the dylib means std::print would not be available on
Apple backdeployment targets. On POSIX platforms there is no transcoding
required so a not Standard conforming implementation is still a useful
and the observable differences are minimal. This behaviour has been done
for print before https://github.com/llvm/llvm-project/pull/76293.

Note questions have been raised in LWG4044 "Confusing requirements for
std::print on POSIX platforms", whether or not the isatty check on POSIX
platforms is required. When this LWG issue is resolved the
backdeployment targets could become Standard compliant.

This patch is intended to be backported to the LLVM-18 branch.

Fixes: https://github.com/llvm/llvm-project/issues/79782
(cherry picked from commit 4fb7b3301bfbd439eb3d30d6a36c7cdb26941a0d)

diff --git a/libcxx/include/print b/libcxx/include/print
index 7f2b5bac3dcf612976580385b3ab712f12fa38c7..543a540ee4f27da029d8300ba83dfd124dd6a97b 100644 (file)
--- a/libcxx/include/print
+++ b/libcxx/include/print
@@ -32,6 +32,7 @@ namespace std {
 */
 
 #include <__assert> // all public C++ headers provide the assertion handler
+#include <__availability>
 #include <__concepts/same_as.h>
 #include <__config>
 #include <__system_error/system_error.h>
@@ -43,10 +44,6 @@ namespace std {
 #include <string_view>
 #include <version>
 
-#if __has_include(<unistd.h>)
-#  include <unistd.h>
-#endif
-
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
@@ -68,7 +65,8 @@ _LIBCPP_EXPORTED_FROM_ABI bool __is_windows_terminal(FILE* __stream);
 // Note the function is only implemented on the Windows platform.
 _LIBCPP_EXPORTED_FROM_ABI void __write_to_windows_console(FILE* __stream, wstring_view __view);
 #  endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
-
+#elif __has_include(<unistd.h>)
+_LIBCPP_EXPORTED_FROM_ABI bool __is_posix_terminal(FILE* __stream);
 #endif // _LIBCPP_WIN32API
 
 #if _LIBCPP_STD_VER >= 23
@@ -195,15 +193,17 @@ inline constexpr bool __use_unicode_execution_charset = _MSVC_EXECUTION_CHARACTE
 inline constexpr bool __use_unicode_execution_charset = true;
 #  endif
 
-_LIBCPP_HIDE_FROM_ABI inline bool __is_terminal(FILE* __stream) {
+_LIBCPP_HIDE_FROM_ABI inline bool __is_terminal([[maybe_unused]] FILE* __stream) {
   // The macro _LIBCPP_TESTING_PRINT_IS_TERMINAL is used to change
   // the behavior in the test. This is not part of the public API.
 #  ifdef _LIBCPP_TESTING_PRINT_IS_TERMINAL
   return _LIBCPP_TESTING_PRINT_IS_TERMINAL(__stream);
+#  elif _LIBCPP_AVAILABILITY_HAS_PRINT == 0
+  return false;
 #  elif defined(_LIBCPP_WIN32API)
   return std::__is_windows_terminal(__stream);
 #  elif __has_include(<unistd.h>)
-  return isatty(fileno(__stream));
+  return std::__is_posix_terminal(__stream);
 #  else
 #    error "Provide a way to determine whether a FILE* is a terminal"
 #  endif

diff --git a/libcxx/lib/abi/CHANGELOG.TXT b/libcxx/lib/abi/CHANGELOG.TXT
index 1179c253f18c8f77c0af140f3693c82ff5edf9e8..7ff604959f4d5cd071d48cb0f833ced853ede972 100644 (file)
--- a/libcxx/lib/abi/CHANGELOG.TXT
+++ b/libcxx/lib/abi/CHANGELOG.TXT
@@ -16,6 +16,14 @@ New entries should be added directly below the "Version" header.
 Version 18.0
 ------------
 
+* [libc++] Moves is_terminal to the dylib
+
+  The patch moves the POSIX implementation of is_terminal to the dylib. This is
+  needed to avoid using <unistd.h> in public headers.
+
+  All platforms
+  Symbol added: _ZNSt6__ndk119__is_posix_terminalEP7__sFILE
+
 * [libc++abi] Implement __cxa_init_primary_exception and use it to optimize std::make_exception_ptr (#65534)
 
   This patch implements __cxa_init_primary_exception, an extension to the Itanium C++ ABI.

diff --git a/libcxx/lib/abi/arm64-apple-darwin.libcxxabi.v1.stable.exceptions.nonew.abilist b/libcxx/lib/abi/arm64-apple-darwin.libcxxabi.v1.stable.exceptions.nonew.abilist
index c2fea4d8adb420d8772c10d8c4638864e1bd897b..2064f45bf8c084954ce5ea827ecaa9c984e17848 100644 (file)
--- a/libcxx/lib/abi/arm64-apple-darwin.libcxxabi.v1.stable.exceptions.nonew.abilist
+++ b/libcxx/lib/abi/arm64-apple-darwin.libcxxabi.v1.stable.exceptions.nonew.abilist
@@ -1495,6 +1495,7 @@
 {'is_defined': True, 'name': '__ZNSt3__118shared_timed_mutex8try_lockEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__118shared_timed_mutexC1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__118shared_timed_mutexC2Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '__ZNSt3__119__is_posix_terminalEP7__sFILE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__119__shared_mutex_base11lock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__119__shared_mutex_base13unlock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__119__shared_mutex_base15try_lock_sharedEv', 'type': 'FUNC'}

diff --git a/libcxx/lib/abi/i686-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist b/libcxx/lib/abi/i686-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist
index a60f099b5320522d39f0f35cf81186a113b6b8a2..fec3a4505a0c6d8c251848a085d19f8d61f22429 100644 (file)
--- a/libcxx/lib/abi/i686-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist
+++ b/libcxx/lib/abi/i686-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist
@@ -1176,6 +1176,7 @@
 {'is_defined': True, 'name': '_ZNSt6__ndk118shared_timed_mutex8try_lockEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk118shared_timed_mutexC1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk118shared_timed_mutexC2Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '_ZNSt6__ndk119__is_posix_terminalEP7__sFILE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk119__shared_mutex_base11lock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk119__shared_mutex_base13unlock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk119__shared_mutex_base15try_lock_sharedEv', 'type': 'FUNC'}

diff --git a/libcxx/lib/abi/powerpc-ibm-aix.libcxxabi.v1.stable.exceptions.nonew.abilist b/libcxx/lib/abi/powerpc-ibm-aix.libcxxabi.v1.stable.exceptions.nonew.abilist
index a159ff522186678155bf400dd1b0d7426f2561b4..e52cf98dd4c4f1e2ade186ac28351adb7f5780a9 100644 (file)
--- a/libcxx/lib/abi/powerpc-ibm-aix.libcxxabi.v1.stable.exceptions.nonew.abilist
+++ b/libcxx/lib/abi/powerpc-ibm-aix.libcxxabi.v1.stable.exceptions.nonew.abilist
@@ -534,6 +534,7 @@
 {'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutex8try_lockEv', 'storage_mapping_class': 'DS', 'type': 'FUNC'}
 {'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutexC1Ev', 'storage_mapping_class': 'DS', 'type': 'FUNC'}
 {'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutexC2Ev', 'storage_mapping_class': 'DS', 'type': 'FUNC'}
+{'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__119__is_posix_terminalEP4FILE', 'storage_mapping_class': 'DS', 'type': 'FUNC'}
 {'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base11lock_sharedEv', 'storage_mapping_class': 'DS', 'type': 'FUNC'}
 {'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base13unlock_sharedEv', 'storage_mapping_class': 'DS', 'type': 'FUNC'}
 {'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base15try_lock_sharedEv', 'storage_mapping_class': 'DS', 'type': 'FUNC'}

diff --git a/libcxx/lib/abi/powerpc64-ibm-aix.libcxxabi.v1.stable.exceptions.nonew.abilist b/libcxx/lib/abi/powerpc64-ibm-aix.libcxxabi.v1.stable.exceptions.nonew.abilist
index 5749a7520f9bac1d7a6090e1957e4611197df885..52a04706ddf20bfb54914ceefd6a650c1f2cd647 100644 (file)
--- a/libcxx/lib/abi/powerpc64-ibm-aix.libcxxabi.v1.stable.exceptions.nonew.abilist
+++ b/libcxx/lib/abi/powerpc64-ibm-aix.libcxxabi.v1.stable.exceptions.nonew.abilist
@@ -534,6 +534,7 @@
 {'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutex8try_lockEv', 'storage_mapping_class': 'DS', 'type': 'FUNC'}
 {'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutexC1Ev', 'storage_mapping_class': 'DS', 'type': 'FUNC'}
 {'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutexC2Ev', 'storage_mapping_class': 'DS', 'type': 'FUNC'}
+{'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__119__is_posix_terminalEP4FILE', 'storage_mapping_class': 'DS', 'type': 'FUNC'}
 {'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base11lock_sharedEv', 'storage_mapping_class': 'DS', 'type': 'FUNC'}
 {'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base13unlock_sharedEv', 'storage_mapping_class': 'DS', 'type': 'FUNC'}
 {'import_export': 'EXP', 'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base15try_lock_sharedEv', 'storage_mapping_class': 'DS', 'type': 'FUNC'}

diff --git a/libcxx/lib/abi/x86_64-apple-darwin.libcxxabi.v1.stable.exceptions.nonew.abilist b/libcxx/lib/abi/x86_64-apple-darwin.libcxxabi.v1.stable.exceptions.nonew.abilist
index e827114f169197ab3905a06c39066d8b5c1a5a10..bced6b2ea81ba53db899e84f5efb4c87cb8b83e6 100644 (file)
--- a/libcxx/lib/abi/x86_64-apple-darwin.libcxxabi.v1.stable.exceptions.nonew.abilist
+++ b/libcxx/lib/abi/x86_64-apple-darwin.libcxxabi.v1.stable.exceptions.nonew.abilist
@@ -1495,6 +1495,7 @@
 {'is_defined': True, 'name': '__ZNSt3__118shared_timed_mutex8try_lockEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__118shared_timed_mutexC1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__118shared_timed_mutexC2Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '__ZNSt3__119__is_posix_terminalEP7__sFILE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__119__shared_mutex_base11lock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__119__shared_mutex_base13unlock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '__ZNSt3__119__shared_mutex_base15try_lock_sharedEv', 'type': 'FUNC'}

diff --git a/libcxx/lib/abi/x86_64-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist b/libcxx/lib/abi/x86_64-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist
index f4077adc074e0a17c878adf5c8bbecfb0ad3acc8..efa2189e9c92875145cec3ed80e4ebbb66ea7f69 100644 (file)
--- a/libcxx/lib/abi/x86_64-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist
+++ b/libcxx/lib/abi/x86_64-linux-android21.libcxxabi.v1.stable.exceptions.nonew.abilist
@@ -1176,6 +1176,7 @@
 {'is_defined': True, 'name': '_ZNSt6__ndk118shared_timed_mutex8try_lockEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk118shared_timed_mutexC1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk118shared_timed_mutexC2Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '_ZNSt6__ndk119__is_posix_terminalEP7__sFILE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk119__shared_mutex_base11lock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk119__shared_mutex_base13unlock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt6__ndk119__shared_mutex_base15try_lock_sharedEv', 'type': 'FUNC'}

diff --git a/libcxx/lib/abi/x86_64-unknown-freebsd.libcxxabi.v1.stable.exceptions.nonew.abilist b/libcxx/lib/abi/x86_64-unknown-freebsd.libcxxabi.v1.stable.exceptions.nonew.abilist
index e3d3fcb35d8403ae93db116bfa31cbab00e1ed42..ebda5b0dfba57de4c8445a3f9689fc836b06961a 100644 (file)
--- a/libcxx/lib/abi/x86_64-unknown-freebsd.libcxxabi.v1.stable.exceptions.nonew.abilist
+++ b/libcxx/lib/abi/x86_64-unknown-freebsd.libcxxabi.v1.stable.exceptions.nonew.abilist
@@ -1190,6 +1190,7 @@
 {'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutex8try_lockEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutexC1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutexC2Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '_ZNSt3__119__is_posix_terminalEP7__sFILE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base11lock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base13unlock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base15try_lock_sharedEv', 'type': 'FUNC'}

diff --git a/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.nonew.abilist b/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.nonew.abilist
index 16923301d2548ebcec83556a27cf6f67699d013f..6432ad3be358595084afbcbc32c6849704e4b8f3 100644 (file)
--- a/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.nonew.abilist
+++ b/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.exceptions.nonew.abilist
@@ -1188,6 +1188,7 @@
 {'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutex8try_lockEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutexC1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutexC2Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '_ZNSt3__119__is_posix_terminalEP8_IO_FILE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base11lock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base13unlock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base15try_lock_sharedEv', 'type': 'FUNC'}

diff --git a/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.noexceptions.nonew.abilist b/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.noexceptions.nonew.abilist
index 2380ffb100de973ec602fdf906edeb7f4291aeba..1fe84e17b3f7f05bfb0d590f9e174392cec45af4 100644 (file)
--- a/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.noexceptions.nonew.abilist
+++ b/libcxx/lib/abi/x86_64-unknown-linux-gnu.libcxxabi.v1.stable.noexceptions.nonew.abilist
@@ -1159,6 +1159,7 @@
 {'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutex8try_lockEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutexC1Ev', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__118shared_timed_mutexC2Ev', 'type': 'FUNC'}
+{'is_defined': True, 'name': '_ZNSt3__119__is_posix_terminalEP8_IO_FILE', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base11lock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base13unlock_sharedEv', 'type': 'FUNC'}
 {'is_defined': True, 'name': '_ZNSt3__119__shared_mutex_base15try_lock_sharedEv', 'type': 'FUNC'}

diff --git a/libcxx/src/print.cpp b/libcxx/src/print.cpp
index 3692187a5954a3229671754a6cf88497d7f622e2..8fa59fdd097bcd811cf78f9e4d90871858f93fec 100644 (file)
--- a/libcxx/src/print.cpp
+++ b/libcxx/src/print.cpp
@@ -8,22 +8,26 @@
 
 #include <__config>
 
-#if defined(_LIBCPP_WIN32API)
+#include <cstdlib>
+#include <print>
+
+#include <__system_error/system_error.h>
 
-#  include <cstdlib>
-#  include <print>
+#include "filesystem/error.h"
 
+#if defined(_LIBCPP_WIN32API)
 #  define WIN32_LEAN_AND_MEAN
 #  define NOMINMAX
 #  include <io.h>
 #  include <windows.h>
-
-#  include <__system_error/system_error.h>
-
-#  include "filesystem/error.h"
+#elif __has_include(<unistd.h>)
+#  include <unistd.h>
+#endif
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
+#if defined(_LIBCPP_WIN32API)
+
 _LIBCPP_EXPORTED_FROM_ABI bool __is_windows_terminal(FILE* __stream) {
   // Note the Standard does this in one call, but it's unclear whether
   // an invalid handle is allowed when calling GetConsoleMode.
@@ -52,6 +56,9 @@ __write_to_windows_console([[maybe_unused]] FILE* __stream, [[maybe_unused]] wst
 }
 #  endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
 
-_LIBCPP_END_NAMESPACE_STD
+#elif __has_include(<unistd.h>) // !_LIBCPP_WIN32API
 
-#endif // !_LIBCPP_WIN32API
+_LIBCPP_EXPORTED_FROM_ABI bool __is_posix_terminal(FILE* __stream) { return isatty(fileno(__stream)); }
+#endif
+
+_LIBCPP_END_NAMESPACE_STD