minicrossterm/crossterm_winapi/src/screen_buffer.rs
2019-09-20 23:50:53 +02:00

138 lines
4.2 KiB
Rust

//! This contains the logic for working with the console buffer.
use std::io::{Error, Result};
use std::mem::size_of;
use winapi::{
shared::minwindef::TRUE,
shared::ntdef::NULL,
um::{
minwinbase::SECURITY_ATTRIBUTES,
wincon::{
CreateConsoleScreenBuffer, GetConsoleScreenBufferInfo, SetConsoleActiveScreenBuffer,
SetConsoleScreenBufferSize, CONSOLE_TEXTMODE_BUFFER, COORD,
},
winnt::{FILE_SHARE_READ, FILE_SHARE_WRITE, GENERIC_READ, GENERIC_WRITE, HANDLE},
},
};
use super::{is_true, Handle, HandleType, ScreenBufferInfo};
pub struct ScreenBuffer {
handle: Handle,
}
impl ScreenBuffer {
/// Create an instance of `ScreenBuffer` where the `HANDLE`, used for the functions this type wraps, is the current output handle.
pub fn current() -> Result<ScreenBuffer> {
Ok(ScreenBuffer {
handle: Handle::new(HandleType::CurrentOutputHandle)?,
})
}
/// Create new console screen buffer.
///
/// Wraps the underlying function call: [CreateConsoleScreenBuffer]
/// link: [https://docs.microsoft.com/en-us/windows/console/createconsolescreenbuffer]
pub fn create() -> ScreenBuffer {
let mut security_attr: SECURITY_ATTRIBUTES = SECURITY_ATTRIBUTES {
nLength: size_of::<SECURITY_ATTRIBUTES>() as u32,
lpSecurityDescriptor: NULL,
bInheritHandle: TRUE,
};
unsafe {
let new_screen_buffer = CreateConsoleScreenBuffer(
GENERIC_READ | // read/write access
GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE, // shared
&mut security_attr, // default security attributes
CONSOLE_TEXTMODE_BUFFER, // must be TEXTMODE
NULL,
);
ScreenBuffer {
handle: Handle::from(new_screen_buffer),
}
}
}
/// This will make this `ScreenBuffer` the active one.
///
/// Wraps the underlying function call: [SetConsoleActiveScreenBuffer]
/// link: [https://docs.microsoft.com/en-us/windows/console/setconsoleactivescreenbuffer]
pub fn show(&self) -> Result<()> {
unsafe {
if !is_true(SetConsoleActiveScreenBuffer(*self.handle)) {
return Err(Error::last_os_error());
}
}
Ok(())
}
/// Get the screen buffer information like terminal size, cursor position, buffer size.
///
/// Wraps the underlying function call: [GetConsoleScreenBufferInfo]
/// link: [https://docs.microsoft.com/en-us/windows/console/getconsolescreenbufferinfo]
pub fn info(&self) -> Result<ScreenBufferInfo> {
let mut csbi = ScreenBufferInfo::new();
unsafe {
if !is_true(GetConsoleScreenBufferInfo(*self.handle, &mut csbi.0)) {
return Err(Error::last_os_error());
}
}
Ok(csbi)
}
/// Set the console screen buffer size to the given size.
///
/// Wraps the underlying function call: [SetConsoleScreenBufferSize]
/// link: [https://docs.microsoft.com/en-us/windows/console/setconsolescreenbuffersize]
pub fn set_size(&self, x: i16, y: i16) -> Result<()> {
unsafe {
if !is_true(SetConsoleScreenBufferSize(
*self.handle,
COORD { X: x, Y: y },
)) {
return Err(Error::last_os_error());
}
}
Ok(())
}
/// Get the underlining raw `HANDLE` used by this type to execute whit.
pub fn handle(&self) -> &Handle {
return &self.handle;
}
}
impl From<Handle> for ScreenBuffer {
fn from(handle: Handle) -> Self {
ScreenBuffer { handle }
}
}
impl From<HANDLE> for ScreenBuffer {
fn from(handle: HANDLE) -> Self {
ScreenBuffer {
handle: Handle::from(handle),
}
}
}
#[cfg(test)]
mod tests {
use super::ScreenBuffer;
#[test]
fn test_screen_buffer_info() {
let buffer = ScreenBuffer::current().unwrap();
let info = buffer.info().unwrap();
info.terminal_size();
info.terminal_window();
info.attributes();
info.cursor_pos();
}
}