From c43c6aa562c5222477f66d50179e368ca0f25a9b Mon Sep 17 00:00:00 2001
From: Philipp Gesang <phg@phi-gamma.net>
Date: Mon, 15 Nov 2021 20:55:30 +0100
Subject: turn Fd into proper wrapper

---
 src/lib.rs   | 30 +++++++++++++++++++++++++-----
 src/vtcol.rs | 30 ++++++++++++++----------------
 2 files changed, 39 insertions(+), 21 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index 47f650d..f8bef99 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -2,9 +2,29 @@ use libc::ioctl;
 use std::{convert::TryFrom,
           fmt,
           io::{self, BufWriter, Error, Write},
+          os::unix::io::{AsRawFd, RawFd},
           path::{Path, PathBuf}};
 
-pub type Fd = libc::c_int;
+#[derive(Debug)]
+pub struct Fd(libc::c_int);
+
+impl From<libc::c_int> for Fd
+{
+    fn from(fd: libc::c_int) -> Self { Self(fd) }
+}
+
+impl AsRawFd for Fd
+{
+    fn as_raw_fd(&self) -> RawFd { self.0 }
+}
+
+impl fmt::Display for Fd
+{
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result
+    {
+        write!(f, "Fd({})", self.0)
+    }
+}
 
 const PALETTE_SIZE: usize = 16;
 const PALETTE_BYTES: usize = PALETTE_SIZE * 3; /* 16 * sizeof(int) */
@@ -493,11 +513,11 @@ impl From<&RawPalette<'_>> for Palette
     }
 }
 
-pub fn ioctl_pio_cmap(fd: Fd, pal: &Palette) -> io::Result<()>
+pub fn ioctl_pio_cmap<F: AsRawFd>(fd: &F, pal: &Palette) -> io::Result<()>
 {
     if unsafe {
         ioctl(
-            fd,
+            fd.as_raw_fd(),
             PIO_CMAP,
             std::mem::transmute::<&Palette, *const libc::c_void>(&pal),
         )
@@ -509,13 +529,13 @@ pub fn ioctl_pio_cmap(fd: Fd, pal: &Palette) -> io::Result<()>
     }
 }
 
-pub fn ioctl_gio_cmap(fd: Fd) -> io::Result<Palette>
+pub fn ioctl_gio_cmap<F: AsRawFd>(fd: &F) -> io::Result<Palette>
 {
     let mut pal = Palette::new();
 
     if unsafe {
         ioctl(
-            fd,
+            fd.as_raw_fd(),
             GIO_CMAP,
             std::mem::transmute::<&mut Palette, *mut libc::c_void>(&mut pal),
         )
diff --git a/src/vtcol.rs b/src/vtcol.rs
index 2c41d7b..0cc713c 100644
--- a/src/vtcol.rs
+++ b/src/vtcol.rs
@@ -1,9 +1,10 @@
 pub mod lib;
 
-use vtcol::{Palette, Scheme};
+use vtcol::{Fd, Palette, Scheme};
 
 use anyhow::{anyhow, Result};
 use std::{io::{self, BufWriter, Error},
+          os::unix::io::AsRawFd,
           sync::atomic::{AtomicBool, Ordering}};
 
 static VERBOSITY: AtomicBool = AtomicBool::new(false);
@@ -225,9 +226,9 @@ impl<'a> Job
         let fd = get_console_fd()?;
         vrb!("console fd: {}", fd);
 
-        vtcol::ioctl_pio_cmap(fd, &pal)?;
+        vtcol::ioctl_pio_cmap(&fd, &pal)?;
 
-        clear_term(fd)?;
+        clear_term(&fd)?;
         vrb!("successfully enabled scheme {:?}", scheme);
         /* It’s fine to leak the fd, the kernel will clean up anyways. */
         Ok(())
@@ -238,7 +239,7 @@ impl<'a> Job
         let fd = get_console_fd()?;
         vrb!("console fd: {}", fd);
 
-        let pal = vtcol::ioctl_gio_cmap(fd)?;
+        let pal = vtcol::ioctl_gio_cmap(&fd)?;
         let scm = Scheme::from(pal);
 
         vrb!("active scheme:");
@@ -255,7 +256,7 @@ impl<'a> Job
         let fd = get_console_fd()?;
         vrb!("console fd: {}", fd);
 
-        let pal = vtcol::ioctl_gio_cmap(fd)?;
+        let pal = vtcol::ioctl_gio_cmap(&fd)?;
 
         if pal == Palette::from(&one) {
             Self::set_scheme(two)
@@ -289,11 +290,7 @@ fn fd_of_path(path: &std::path::Path) -> Option<vtcol::Fd>
             let mut tty_type: libc::c_char = 0;
 
             let res = unsafe {
-                libc::ioctl(
-                    fd,
-                    vtcol::KDGKBTYPE,
-                    &mut tty_type as *mut _
-                )
+                libc::ioctl(fd, vtcol::KDGKBTYPE, &mut tty_type as *mut _)
             };
             if res < 0 {
                 vrb!("  *> ioctl failed");
@@ -304,12 +301,12 @@ fn fd_of_path(path: &std::path::Path) -> Option<vtcol::Fd>
                 return None;
             }
 
-            Some(fd)
+            Some(Fd::from(fd))
         },
     }
 }
 
-fn get_console_fd() -> Result<vtcol::Fd>
+fn get_console_fd() -> Result<Fd>
 {
     for path in CONSOLE_PATHS.iter() {
         vrb!("trying path: {:?}", path);
@@ -322,12 +319,13 @@ fn get_console_fd() -> Result<vtcol::Fd>
     Err(anyhow!("could not retrieve fd for any of the search paths"))
 }
 
-fn write_to_term(fd: vtcol::Fd, buf: &str) -> Result<()>
+fn write_to_term(fd: &Fd, buf: &str) -> Result<()>
 {
     let len = buf.len() as libc::size_t;
 
-    if unsafe { libc::write(fd, buf.as_ptr() as *const libc::c_void, len) }
-        != len as isize
+    if unsafe {
+        libc::write(fd.as_raw_fd(), buf.as_ptr() as *const libc::c_void, len)
+    } != len as isize
     {
         Err(anyhow!(
             "failed to write {} B to fd {}: {}",
@@ -340,7 +338,7 @@ fn write_to_term(fd: vtcol::Fd, buf: &str) -> Result<()>
     }
 }
 
-fn clear_term(fd: vtcol::Fd) -> Result<()>
+fn clear_term(fd: &Fd) -> Result<()>
 {
     let clear = "\x1b[2J";
     let cursor = "\x1b[1;1H";
-- 
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