diff options
author | Ben S <ogham@bsago.me> | 2015-09-04 11:30:46 +0100 |
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committer | Ben S <ogham@bsago.me> | 2015-09-04 11:30:46 +0100 |
commit | 65967355a88a4e6503e01e88100dedc3195109de (patch) | |
tree | c9fe10f6e7f37e1f99434e2cbd86fcaf89eabc56 | |
parent | d1e682b0c185449802b060555fee035233b8e154 (diff) |
Make sure we check the ioctl term size result
-rw-r--r-- | src/main.rs | 1 | ||||
-rw-r--r-- | src/options.rs | 1 | ||||
-rw-r--r-- | src/term.rs | 60 |
3 files changed, 39 insertions, 23 deletions
diff --git a/src/main.rs b/src/main.rs index 54b753e..02f6ba9 100644 --- a/src/main.rs +++ b/src/main.rs @@ -4,6 +4,7 @@ #![warn(trivial_casts, trivial_numeric_casts)] #![warn(unused_extern_crates, unused_qualifications)] +#![warn(unused_results)] extern crate ansi_term; extern crate datetime; diff --git a/src/options.rs b/src/options.rs index 44d055f..bf2f4a3 100644 --- a/src/options.rs +++ b/src/options.rs @@ -28,6 +28,7 @@ pub struct Options { impl Options { /// Call getopts on the given slice of command-line strings. + #[allow(unused_results)] pub fn getopts(args: &[String]) -> Result<(Options, Vec<String>), Misfire> { let mut opts = getopts::Options::new(); opts.optflag("1", "oneline", "display one entry per line"); diff --git a/src/term.rs b/src/term.rs index 4c2ba18..87ea242 100644 --- a/src/term.rs +++ b/src/term.rs @@ -1,39 +1,53 @@ -mod c { - use std::mem::zeroed; - use libc::{c_int, c_ushort, c_ulong, STDOUT_FILENO}; +//! System calls for getting the terminal size. +//! +//! Getting the terminal size is performed using an ioctl command that takes +//! the file handle to the terminal -- which in this case, is stdout -- and +//! populates a structure containing the values. +//! +//! The size is needed when the user wants the output formatted into columns: +//! the default grid view, or the hybrid grid-details view. + +use std::mem::zeroed; +use libc::{c_int, c_ushort, c_ulong, STDOUT_FILENO}; + + +/// The number of rows and columns of a terminal. +struct Winsize { + ws_row: c_ushort, + ws_col: c_ushort, +} - // Getting the terminal size is done using an ioctl command that - // takes the file handle to the terminal (which in our case is - // stdout), and populates a structure with the values. +// Unfortunately the actual command is not standardised... - pub struct Winsize { - pub ws_row: c_ushort, - pub ws_col: c_ushort, - } +#[cfg(any(target_os = "linux", target_os = "android"))] +static TIOCGWINSZ: c_ulong = 0x5413; - // Unfortunately the actual command is not standardised... +#[cfg(any(target_os = "macos", target_os = "ios", target_os = "dragonfly"))] +static TIOCGWINSZ: c_ulong = 0x40087468; - #[cfg(any(target_os = "linux", target_os = "android"))] - static TIOCGWINSZ: c_ulong = 0x5413; +extern { + pub fn ioctl(fd: c_int, request: c_ulong, ...) -> c_int; +} - #[cfg(any(target_os = "macos", target_os = "ios", target_os = "dragonfly"))] - static TIOCGWINSZ: c_ulong = 0x40087468; +/// Runs the ioctl command. Returns (0, 0) if output is not to a terminal, or +/// there is an error. (0, 0) is an invalid size to have anyway, which is why +/// it can be used as a nil value. +unsafe fn get_dimensions() -> Winsize { + let mut window: Winsize = zeroed(); + let result = ioctl(STDOUT_FILENO, TIOCGWINSZ, &mut window); - extern { - pub fn ioctl(fd: c_int, request: c_ulong, ...) -> c_int; + if result == -1 { + zeroed() } - - pub unsafe fn dimensions() -> Winsize { - let mut window: Winsize = zeroed(); - ioctl(STDOUT_FILENO, TIOCGWINSZ, &mut window); + else { window } } /// Query the current processes's output, returning its width and height as a -/// number of characters. Returns None if the output isn't to a terminal. +/// number of characters. Returns `None` if the output isn't to a terminal. pub fn dimensions() -> Option<(usize, usize)> { - let w = unsafe { c::dimensions() }; + let w = unsafe { get_dimensions() }; if w.ws_col == 0 || w.ws_row == 0 { None |