Vendor things

third-party/vendor/nu-ansi-term/src/windows.rs

@@ -0,0 +1,62 @@
+/// Enables ANSI code support on Windows 10.
+///
+/// This uses Windows API calls to alter the properties of the console that
+/// the program is running in.
+///
+/// https://msdn.microsoft.com/en-us/library/windows/desktop/mt638032(v=vs.85).aspx
+///
+/// Returns a `Result` with the Windows error code if unsuccessful.
+#[cfg(windows)]
+pub fn enable_ansi_support() -> Result<(), u32> {
+    // ref: https://docs.microsoft.com/en-us/windows/console/console-virtual-terminal-sequences#EXAMPLE_OF_ENABLING_VIRTUAL_TERMINAL_PROCESSING @@ https://archive.is/L7wRJ#76%
+
+    use std::ffi::OsStr;
+    use std::iter::once;
+    use std::os::windows::ffi::OsStrExt;
+    use std::ptr::null_mut;
+    use winapi::um::consoleapi::{GetConsoleMode, SetConsoleMode};
+    use winapi::um::errhandlingapi::GetLastError;
+    use winapi::um::fileapi::{CreateFileW, OPEN_EXISTING};
+    use winapi::um::handleapi::INVALID_HANDLE_VALUE;
+    use winapi::um::winnt::{FILE_SHARE_WRITE, GENERIC_READ, GENERIC_WRITE};
+
+    const ENABLE_VIRTUAL_TERMINAL_PROCESSING: u32 = 0x0004;
+
+    unsafe {
+        // ref: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilew
+        // Using `CreateFileW("CONOUT$", ...)` to retrieve the console handle works correctly even if STDOUT and/or STDERR are redirected
+        let console_out_name: Vec<u16> =
+            OsStr::new("CONOUT$").encode_wide().chain(once(0)).collect();
+        let console_handle = CreateFileW(
+            console_out_name.as_ptr(),
+            GENERIC_READ | GENERIC_WRITE,
+            FILE_SHARE_WRITE,
+            null_mut(),
+            OPEN_EXISTING,
+            0,
+            null_mut(),
+        );
+        if console_handle == INVALID_HANDLE_VALUE {
+            return Err(GetLastError());
+        }
+
+        // ref: https://docs.microsoft.com/en-us/windows/console/getconsolemode
+        let mut console_mode: u32 = 0;
+        if 0 == GetConsoleMode(console_handle, &mut console_mode) {
+            return Err(GetLastError());
+        }
+
+        // VT processing not already enabled?
+        if console_mode & ENABLE_VIRTUAL_TERMINAL_PROCESSING == 0 {
+            // https://docs.microsoft.com/en-us/windows/console/setconsolemode
+            if 0 == SetConsoleMode(
+                console_handle,
+                console_mode | ENABLE_VIRTUAL_TERMINAL_PROCESSING,
+            ) {
+                return Err(GetLastError());
+            }
+        }
+    }
+
+    Ok(())
+}