fix: if Win10, then enable Ansi support

more info about this at https://stackoverflow.com/a/51681675/675577
dialex · Dec 30, 2019 · baa3b95 · baa3b95
1 parent 094a305
commit baa3b95
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diff --git a/pom.xml b/pom.xml
@@ -151,6 +151,18 @@
     </build>
 
     <dependencies>
+        <!-- Necessary for Windows 10 Ansi support -->
+        <dependency>
+            <groupId>net.java.dev.jna</groupId>
+            <artifactId>jna</artifactId>
+            <version>5.5.0</version>
+        </dependency>
+        <dependency>
+            <groupId>net.java.dev.jna</groupId>
+            <artifactId>jna-platform</artifactId>
+            <version>5.5.0</version>
+        </dependency>
+        <!-- Dependencies of test framework -->
         <dependency>
             <groupId>org.hamcrest</groupId>
             <artifactId>hamcrest-library</artifactId>

diff --git a/src/main/java/com/diogonunes/jcdp/color/ColoredPrinter.java b/src/main/java/com/diogonunes/jcdp/color/ColoredPrinter.java
@@ -7,6 +7,11 @@
 import com.diogonunes.jcdp.color.api.Ansi.BColor;
 import com.diogonunes.jcdp.color.api.Ansi.FColor;
 import com.diogonunes.jcdp.color.api.IColoredPrinter;
+import com.sun.jna.Function;
+import com.sun.jna.platform.win32.WinDef.BOOL;
+import com.sun.jna.platform.win32.WinDef.DWORD;
+import com.sun.jna.platform.win32.WinDef.DWORDByReference;
+import com.sun.jna.platform.win32.WinNT.HANDLE;
 
 import java.text.DateFormat;
 import java.text.SimpleDateFormat;
@@ -41,6 +46,9 @@ public ColoredPrinter(Builder builder) {
         setAttribute(builder._attribute);
         setForegroundColor(builder._foregroundColor);
         setBackgroundColor(builder._backgroundColor);
+
+        if (System.getProperty("os.name").startsWith("Windows"))
+            enableWindows10AnsiSupport();
     }
 
     // =========
@@ -313,4 +321,27 @@ private void formattedPrint(Object msg, String ansiFormatCode, boolean appendNew
         String formattedMsg = Ansi.formatMessage(output.toString(), ansiFormatCode);
         System.out.print(formattedMsg);
     }
+
+    /* Windows 10 supports Ansi codes. However, it's still experimental and not enabled by default.
+     * This method enables the necessary Windows 10 feature.
+     *
+     * More info: https://stackoverflow.com/a/51681675/675577
+     * Code source: https://stackoverflow.com/a/52767586/675577
+     * Reported issue: https://github.com/PowerShell/PowerShell/issues/11449#issuecomment-569531747
+     */
+    private void enableWindows10AnsiSupport() {
+        Function GetStdHandleFunc = Function.getFunction("kernel32", "GetStdHandle");
+        DWORD STD_OUTPUT_HANDLE = new DWORD(-11);
+        HANDLE hOut = (HANDLE) GetStdHandleFunc.invoke(HANDLE.class, new Object[]{STD_OUTPUT_HANDLE});
+
+        DWORDByReference p_dwMode = new DWORDByReference(new DWORD(0));
+        Function GetConsoleModeFunc = Function.getFunction("kernel32", "GetConsoleMode");
+        GetConsoleModeFunc.invoke(BOOL.class, new Object[]{hOut, p_dwMode});
+
+        int ENABLE_VIRTUAL_TERMINAL_PROCESSING = 4;
+        DWORD dwMode = p_dwMode.getValue();
+        dwMode.setValue(dwMode.intValue() | ENABLE_VIRTUAL_TERMINAL_PROCESSING);
+        Function SetConsoleModeFunc = Function.getFunction("kernel32", "SetConsoleMode");
+        SetConsoleModeFunc.invoke(BOOL.class, new Object[]{hOut, dwMode});
+    }
 }