Merge pull request #178 from flagarde/master

Add has_ansi_escape_code()

Author: staxfur

cpp-terminal/private/platform.cpp

@@ -4,26 +4,24 @@
 #include <conio.h>
 #include <io.h>
 #include <windows.h>
-#else
-#include <sys/ioctl.h>
-#include <termios.h>
-#include <unistd.h>
-#include <cerrno>
-#endif
-
-#include <stdexcept>
-
+typedef NTSTATUS(WINAPI* RtlGetVersionPtr)(PRTL_OSVERSIONINFOW);
 #ifndef ENABLE_VIRTUAL_TERMINAL_PROCESSING
 #define ENABLE_VIRTUAL_TERMINAL_PROCESSING 0x0004
 #endif
-
 #ifndef DISABLE_NEWLINE_AUTO_RETURN
 #define DISABLE_NEWLINE_AUTO_RETURN 0x0008
 #endif
-
 #ifndef ENABLE_VIRTUAL_TERMINAL_INPUT
 #define ENABLE_VIRTUAL_TERMINAL_INPUT 0x0200
 #endif
+#else
+#include <sys/ioctl.h>
+#include <termios.h>
+#include <unistd.h>
+#include <cerrno>
+#endif
+
+#include <stdexcept>
 
 bool Term::Private::is_stdin_a_tty() {
 #ifdef _WIN32
@@ -116,6 +114,40 @@ bool Term::Private::read_raw(char* s) {
 #endif
 }
 
+bool Term::Private::has_ansi_escape_code() {
+#ifdef _WIN32
+    static bool checked{false};
+    static bool has_ansi{false};
+    if (checked == false) {
+        const DWORD MINV_MAJOR{10};
+        const DWORD MINV_MINOR{0};
+        const DWORD MINV_BUILD{10586};
+        HMODULE hMod{GetModuleHandle(TEXT("ntdll.dll"))};
+        if (hMod) {
+            RtlGetVersionPtr fn = {reinterpret_cast<RtlGetVersionPtr>(
+                GetProcAddress(hMod, "RtlGetVersion"))};
+            if (fn != nullptr) {
+                RTL_OSVERSIONINFOW rovi{0};
+                rovi.dwOSVersionInfoSize = sizeof(rovi);
+                if (fn(&rovi) == 0) {
+                    if (rovi.dwMajorVersion > MINV_MAJOR ||
+                        (rovi.dwMajorVersion == MINV_MAJOR &&
+                         (rovi.dwMinorVersion > MINV_MINOR ||
+                          (rovi.dwMinorVersion == MINV_MINOR &&
+                           rovi.dwBuildNumber >= MINV_BUILD)))) {
+                        has_ansi = true;
+                    }
+                }
+            }
+        }
+        checked = true;
+    }
+    return has_ansi;
+#else
+    return true;
+#endif
+}
+
 Term::Private::BaseTerminal::~BaseTerminal() noexcept(false) {
 #ifdef _WIN32
     if (out_console) {
@@ -161,7 +193,9 @@ Term::Private::BaseTerminal::BaseTerminal(bool enable_keyboard,
             throw std::runtime_error("GetConsoleMode() failed");
         }
         DWORD flags = dwOriginalOutMode;
-        flags |= ENABLE_VIRTUAL_TERMINAL_PROCESSING;
+        if (has_ansi_escape_code()) {
+            flags |= ENABLE_VIRTUAL_TERMINAL_PROCESSING;
+        }
         flags |= DISABLE_NEWLINE_AUTO_RETURN;
         if (!SetConsoleMode(hout, flags)) {
             throw std::runtime_error("SetConsoleMode() failed");
@@ -179,7 +213,9 @@ Term::Private::BaseTerminal::BaseTerminal(bool enable_keyboard,
             throw std::runtime_error("GetConsoleMode() failed");
         }
         DWORD flags = dwOriginalInMode;
-        flags |= ENABLE_VIRTUAL_TERMINAL_INPUT;
+        if (has_ansi_escape_code()) {
+            flags |= ENABLE_VIRTUAL_TERMINAL_INPUT;
+        }
         flags &= ~(ENABLE_LINE_INPUT | ENABLE_ECHO_INPUT);
         if (!SetConsoleMode(hin, flags)) {
             throw std::runtime_error("SetConsoleMode() failed");

cpp-terminal/private/platform.hpp

@@ -36,6 +36,8 @@ bool get_term_size(int& rows, int& cols);
 // This can't be made inline
 bool read_raw(char* s);
 
+bool has_ansi_escape_code();
+
 /* Note: the code that uses Terminal must be inside try/catch block, otherwise
  * the destructors will not be called when an exception happens and the
  * terminal will not be left in a good state. Terminal uses exceptions when

examples/colors.cpp

@@ -58,6 +58,8 @@ int main() {
                       << "\033[0m";
         }
         std::cout << "\n";
+        std::cout << "Press any key to quit" << std::endl;
+        std::cin.get();
 
     } catch (const std::runtime_error& re) {
         std::cerr << "Runtime error: " << re.what() << std::endl;