Add test for buffering behavior of iostreams

Closes #186
boostorg · Oct 17, 2024 · 7a975e0 · 7a975e0
1 parent 84972e2
commit 7a975e0
Show file tree

Hide file tree

Showing 3 changed files with 46 additions and 19 deletions.
diff --git a/include/boost/nowide/iostream.hpp b/include/boost/nowide/iostream.hpp
@@ -40,7 +40,12 @@ namespace nowide {
         class BOOST_NOWIDE_DECL winconsole_ostream : public std::ostream
         {
         public:
-            winconsole_ostream(bool isBuffered, winconsole_ostream* tieStream);
+            enum class target_stream
+            {
+                output,
+                error
+            };
+            winconsole_ostream(target_stream target, bool isBuffered, winconsole_ostream* tieStream);
             ~winconsole_ostream();
 
         private:

diff --git a/src/iostream.cpp b/src/iostream.cpp
@@ -82,27 +82,26 @@ namespace nowide {
             }
         };
 
-        winconsole_ostream::winconsole_ostream(const bool isBuffered, winconsole_ostream* tieStream) : std::ostream(0)
+        winconsole_ostream::winconsole_ostream(const target_stream target,
+                                               const bool isBuffered,
+                                               winconsole_ostream* tieStream) :
+            std::ostream(0)
         {
-            HANDLE h;
-            if(isBuffered)
-                h = GetStdHandle(STD_OUTPUT_HANDLE);
-            else
-                h = GetStdHandle(STD_ERROR_HANDLE);
+            const HANDLE h = GetStdHandle(target == target_stream::output ? STD_OUTPUT_HANDLE : STD_ERROR_HANDLE);
+
             if(is_atty_handle(h))
             {
                 d.reset(new console_output_buffer(h));
                 std::ostream::rdbuf(d.get());
             } else
             {
-                std::ostream::rdbuf(isBuffered ? std::cout.rdbuf() : std::cerr.rdbuf());
+                std::ostream::rdbuf(target == target_stream::output ? std::cout.rdbuf() : std::cerr.rdbuf());
                 assert(rdbuf());
             }
             if(tieStream)
-            {
                 tie(tieStream);
-                setf(ios_base::unitbuf); // If tieStream is set, this is cerr -> set unbuffered
-            }
+            if(!isBuffered)
+                setf(ios_base::unitbuf);
         }
         winconsole_ostream::~winconsole_ostream()
         {
@@ -144,10 +143,11 @@ namespace nowide {
 #else
 #define BOOST_NOWIDE_INIT_PRIORITY
 #endif
-    detail::winconsole_ostream cout BOOST_NOWIDE_INIT_PRIORITY(true, nullptr);
+    using target_stream = detail::winconsole_ostream::target_stream;
+    detail::winconsole_ostream cout BOOST_NOWIDE_INIT_PRIORITY(target_stream::output, true, nullptr);
     detail::winconsole_istream cin BOOST_NOWIDE_INIT_PRIORITY(&cout);
-    detail::winconsole_ostream cerr BOOST_NOWIDE_INIT_PRIORITY(false, &cout);
-    detail::winconsole_ostream clog BOOST_NOWIDE_INIT_PRIORITY(false, nullptr);
+    detail::winconsole_ostream cerr BOOST_NOWIDE_INIT_PRIORITY(target_stream::error, false, &cout);
+    detail::winconsole_ostream clog BOOST_NOWIDE_INIT_PRIORITY(target_stream::error, true, nullptr);
 } // namespace nowide
 } // namespace boost
 

diff --git a/test/test_iostream.cpp b/test/test_iostream.cpp
@@ -35,6 +35,11 @@ const std::string outputString =
 const bool usesNowideRdBufIn = nw::cin.rdbuf() != std::cin.rdbuf();
 const bool usesNowideRdBufOut = nw::cout.rdbuf() != std::cout.rdbuf();
 
+bool is_buffered(const std::ostream& os)
+{
+    return (os.flags() & std::ios_base::unitbuf) == 0;
+}
+
 #ifndef BOOST_NOWIDE_TEST_INTERACTIVE
 class mock_output_buffer final : public nw::detail::console_output_buffer_base
 {
@@ -134,12 +139,14 @@ void test_is_valid_UTF8()
     TEST(!is_valid_UTF8(invalid_utf8_tests[0].utf8));        // Detect invalid
 }
 
-void test_tie()
+void test_tie_and_buffered()
 {
     TEST(nw::cin.tie() == &nw::cout);
     TEST(nw::cerr.tie() == &nw::cout);
-    TEST((nw::cerr.flags() & std::ios_base::unitbuf) != 0);
     TEST(nw::clog.tie() == nullptr);
+    TEST(is_buffered(nw::cout));
+    TEST(!is_buffered(nw::cerr));
+    TEST(is_buffered(nw::clog));
 }
 
 void test_putback_and_get()
@@ -233,6 +240,18 @@ void test_cerr()
     TEST_MOCKED(mock_buf.output == nw::widen("aHello World"));
 }
 
+void test_clog()
+{
+    if(usesNowideRdBufOut)
+    {
+        TEST(nw::clog.rdbuf() != std::clog.rdbuf());
+        TEST(nw::clog.rdbuf() != std::cout.rdbuf());
+        TEST(nw::clog.rdbuf() != nw::cin.rdbuf());
+        TEST(nw::clog.rdbuf() != nw::cout.rdbuf());
+        TEST(nw::clog.rdbuf() != nw::cerr.rdbuf());
+    }
+}
+
 void test_cerr_single_char()
 {
     INSTALL_MOCK_BUF(cerr, mock_output_buffer);
@@ -494,7 +513,8 @@ void test_console()
     std::cout << "Test cout console" << std::endl;
     {
         RedirectStdio stdoutHandle(STD_OUTPUT_HANDLE);
-        decltype(nw::cout) cout(true, nullptr);
+        using cout_t = decltype(nw::cout);
+        cout_t cout(cout_t::target_stream::output, true, nullptr);
         TEST(cout.rdbuf() != std::cout.rdbuf());
 
         const std::string testString = "Hello std out\n\xc3\xa4-\xc3\xb6-\xc3\xbc\n";
@@ -507,7 +527,8 @@ void test_console()
     {
         RedirectStdio stderrHandle(STD_ERROR_HANDLE);
 
-        decltype(nw::cerr) cerr(false, nullptr);
+        using cerr_t = decltype(nw::cerr);
+        cerr_t cerr(cerr_t::target_stream::error, false, nullptr);
         TEST(cerr.rdbuf() != std::cerr.rdbuf());
 
         const std::string testString = "Hello std err\n\xc3\xa4-\xc3\xb6-\xc3\xbc\n";
@@ -573,12 +594,13 @@ void test_main(int argc, char** argv, char**)
     test_ctrl_z_is_eof();                    // LCOV_EXCL_LINE
 #else
     test_is_valid_UTF8();
-    test_tie();
+    test_tie_and_buffered();
     test_putback_and_get();
     test_cout();
     test_cout_single_char();
     test_cerr();
     test_cerr_single_char();
+    test_clog();
     test_cin();
     test_cin_getline();
     test_ctrl_z_is_eof();