[gcc r14-6592] libstdc++: Fix std::print test case for Windows

[gcc r14-6592] libstdc++: Fix std::print test case for Windows

[Jonathan Wakely]

https://gcc.gnu.org/g:1d8ac2a74fe37bb3d2fef63ed1ce19bc6f983189

commit r14-6592-g1d8ac2a74fe37bb3d2fef63ed1ce19bc6f983189
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Dec 15 12:58:37 2023 +0000

    libstdc++: Fix std::print test case for Windows
    
    libstdc++-v3/ChangeLog:
    
            * src/c++23/print.cc (__write_to_terminal) [_WIN32]: If handle
            does not refer to the console then just write to it using normal
            file I/O.
            * testsuite/27_io/print/2.cc (as_printed_to_terminal): Print
            error message on failure.
            (test_utf16_transcoding): Adjust for as_printed_to_terminal
            modifying its argument.

Diff:
---
 libstdc++-v3/src/c++23/print.cc         | 13 ++++++++++++-
 libstdc++-v3/testsuite/27_io/print/2.cc |  7 ++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/libstdc++-v3/src/c++23/print.cc b/libstdc++-v3/src/c++23/print.cc
index 2fe7a2e3565..d72ab856017 100644
--- a/libstdc++-v3/src/c++23/print.cc
+++ b/libstdc++-v3/src/c++23/print.cc
@@ -35,7 +35,8 @@
 
 #ifdef _WIN32
 # include <stdio.h>   // _fileno
-# include <io.h>      // _get_osfhandle
+# include <io.h>      // _get_osfhandle, _open_osfhandle, _write
+# include <fcntl.h>   // _O_APPEND
 # include <windows.h> // GetLastError, WriteConsoleW
 #elifdef _GLIBCXX_HAVE_UNISTD_H
 # include <stdio.h>   // fileno
@@ -324,6 +325,16 @@ namespace
     if (!to_valid_utf16(str, wstr))
       ec = std::make_error_code(errc::illegal_byte_sequence);
 
+    // This allows us to test this function with a normal file,
+    // see testsuite/27_io/print/2.cc
+    if (!check_for_console(term))
+      {
+	int fd = _open_osfhandle((intptr_t)term, _O_APPEND);
+	if (_write(fd, wstr.data(), wstr.size() * 2) == -1)
+	  ec = {errno, generic_category()};
+	return ec;
+      }
+
     unsigned long nchars = 0;
     WriteConsoleW(term, wstr.data(), wstr.size(), &nchars, nullptr);
     if (nchars != wstr.size())
diff --git a/libstdc++-v3/testsuite/27_io/print/2.cc b/libstdc++-v3/testsuite/27_io/print/2.cc
index e101201f109..8aa7888e7bd 100644
--- a/libstdc++-v3/testsuite/27_io/print/2.cc
+++ b/libstdc++-v3/testsuite/27_io/print/2.cc
@@ -39,7 +39,11 @@ as_printed_to_terminal(std::string& s)
 #else
   const auto ec = std::__write_to_terminal(strm, s);
 #endif
-  VERIFY( !ec || ec == std::make_error_code(std::errc::illegal_byte_sequence) );
+  if (ec && ec != std::make_error_code(std::errc::illegal_byte_sequence))
+    {
+      std::println("Failed to : {}", ec.message());
+      VERIFY(!ec);
+    }
   std::fclose(strm);
   std::ifstream in(f.path);
   s.assign(std::istreambuf_iterator<char>(in), {});
@@ -114,6 +118,7 @@ test_utf16_transcoding()
   VERIFY( as_printed_to_terminal(s) );
   VERIFY( utf16_from_bytes(s) == s2 );
 
+  s = (const char*)u8"£🇬🇧 €🇪🇺";
   s += " \xa3 10.99 \xee\xdd";
   VERIFY( ! as_printed_to_terminal(s) );
   std::u16string repl = u"\uFFFD";