feat: safe get_dimensions (??)

Author: Sk7Str1p3

Cargo.lock

@@ -15,5 +15,5 @@ image.workspace = true
 [target.'cfg(not(windows))'.dependencies]
 color_quant = "1.1.0"
 base64 = "0.22.1"
-nix = { version = "0.30.1", features = ["poll", "term"] }
+nix = { version = "0.30.1", features = ["poll", "term", "ioctl"] }
 libc = "0.2.177"

image/Cargo.toml

@@ -21,7 +21,7 @@ impl super::ImageBackend for ITermBackend {
         image: &DynamicImage,
         _colors: usize,
     ) -> Result<String> {
-        let tty_size = unsafe { get_dimensions() };
+        let tty_size = get_dimensions()?;
         let width_ratio = f64::from(tty_size.ws_col) / f64::from(tty_size.ws_xpixel);
         let height_ratio = f64::from(tty_size.ws_row) / f64::from(tty_size.ws_ypixel);
 

image/src/iterm.rs

@@ -73,7 +73,7 @@ impl super::ImageBackend for KittyBackend {
         image: &DynamicImage,
         _colors: usize,
     ) -> Result<String> {
-        let tty_size = unsafe { get_dimensions() };
+        let tty_size = get_dimensions()?;
         let width_ratio = f64::from(tty_size.ws_col) / f64::from(tty_size.ws_xpixel);
         let height_ratio = f64::from(tty_size.ws_row) / f64::from(tty_size.ws_ypixel);
 

image/src/kitty.rs

@@ -1,5 +1,6 @@
-use anyhow::Result;
+use anyhow::{bail, Result};
 use image::DynamicImage;
+use nix::pty::Winsize;
 
 #[derive(clap::ValueEnum, Clone, PartialEq, Eq, Debug)]
 pub enum ImageProtocol {
@@ -50,16 +51,23 @@ pub fn get_image_backend(image_protocol: ImageProtocol) -> Option<Box<dyn ImageB
 }
 
 #[cfg(not(windows))]
-unsafe fn get_dimensions() -> libc::winsize {
-    use libc::{ioctl, winsize, STDOUT_FILENO, TIOCGWINSZ};
-    use std::mem::zeroed;
+fn get_dimensions() -> Result<Winsize> {
+    nix::ioctl_read_bad!(ioctl, nix::libc::TIOCGWINSZ, nix::libc::winsize);
 
-    let mut window: winsize = zeroed();
-    let result = ioctl(STDOUT_FILENO, TIOCGWINSZ, &mut window);
+    let mut window = Winsize {
+        ws_col: 0,
+        ws_row: 0,
+        ws_xpixel: 0,
+        ws_ypixel: 0,
+    };
+    let result = unsafe {
+        use std::os::fd::AsRawFd as _;
+        ioctl(std::io::stdout().as_raw_fd(), &mut window)?
+    };
 
     if result == -1 {
-        zeroed()
+        bail!("ioctl error!")
     } else {
-        window
+        Ok(window)
     }
 }

image/src/lib.rs

@@ -66,7 +66,7 @@ impl SixelBackend {
 impl super::ImageBackend for SixelBackend {
     #[allow(clippy::map_entry)]
     fn add_image(&self, lines: Vec<String>, image: &DynamicImage, colors: usize) -> Result<String> {
-        let tty_size = unsafe { get_dimensions() };
+        let tty_size = get_dimensions()?;
         let cw = tty_size.ws_xpixel / tty_size.ws_col;
         let lh = tty_size.ws_ypixel / tty_size.ws_row;
         let width_ratio = 1.0 / cw as f64;