ansi_term/
windows.rs

1/// Enables ANSI code support on Windows 10.
2///
3/// This uses Windows API calls to alter the properties of the console that
4/// the program is running in.
5///
6/// https://msdn.microsoft.com/en-us/library/windows/desktop/mt638032(v=vs.85).aspx
7///
8/// Returns a `Result` with the Windows error code if unsuccessful.
9#[cfg(windows)]
10pub fn enable_ansi_support() -> Result<(), u32> {
11    use winapi::um::processenv::GetStdHandle;
12    use winapi::um::errhandlingapi::GetLastError;
13    use winapi::um::consoleapi::{GetConsoleMode, SetConsoleMode};
14
15    const STD_OUT_HANDLE: u32 = -11i32 as u32;
16    const ENABLE_VIRTUAL_TERMINAL_PROCESSING: u32 = 0x0004;
17
18    unsafe {
19        // https://docs.microsoft.com/en-us/windows/console/getstdhandle
20        let std_out_handle = GetStdHandle(STD_OUT_HANDLE);
21        let error_code = GetLastError();
22        if error_code != 0 { return Err(error_code); }
23        
24        // https://docs.microsoft.com/en-us/windows/console/getconsolemode
25        let mut console_mode: u32 = 0;
26        GetConsoleMode(std_out_handle, &mut console_mode);
27        let error_code = GetLastError();
28        if error_code != 0 { return Err(error_code); }
29
30        // VT processing not already enabled?
31        if console_mode & ENABLE_VIRTUAL_TERMINAL_PROCESSING == 0 {
32            // https://docs.microsoft.com/en-us/windows/console/setconsolemode
33            SetConsoleMode(std_out_handle, console_mode | ENABLE_VIRTUAL_TERMINAL_PROCESSING);
34            let error_code = GetLastError();
35            if error_code != 0 { return Err(error_code); }
36        }
37    }
38
39    return Ok(());
40}