Add env vars to customize screen size (#585)

src/api/console.rs

@@ -1,4 +1,6 @@
 use crate::sys;
+
+use alloc::string::ToString;
 use core::fmt;
 
 pub use crate::sys::console::{EOT_KEY, ETX_KEY};
@@ -105,3 +107,15 @@ pub fn is_printable(c: char) -> bool {
         true // TODO
     }
 }
+
+// The size of the screen in VGA Text Mode is 80x25
+
+pub fn cols() -> usize {
+    let n = 80; // chars
+    sys::process::env("COLS").unwrap_or(n.to_string()).parse().unwrap_or(n)
+}
+
+pub fn rows() -> usize {
+    let n = 25; // lines
+    sys::process::env("ROWS").unwrap_or(n.to_string()).parse().unwrap_or(n)
+}

src/sys/console.rs

@@ -59,22 +59,6 @@ impl FileIO for Console {
     }
 }
 
-pub fn cols() -> usize {
-    if cfg!(feature = "video") {
-        sys::vga::cols()
-    } else {
-        80
-    }
-}
-
-pub fn rows() -> usize {
-    if cfg!(feature = "video") {
-        sys::vga::rows()
-    } else {
-        25
-    }
-}
-
 pub fn has_cursor() -> bool {
     cfg!(feature = "video")
 }

src/sys/vga.rs

@@ -457,14 +457,6 @@ pub fn print_fmt(args: fmt::Arguments) {
     )
 }
 
-pub fn cols() -> usize {
-    BUFFER_WIDTH
-}
-
-pub fn rows() -> usize {
-    BUFFER_HEIGHT
-}
-
 pub fn color() -> (Color, Color) {
     interrupts::without_interrupts(||
         WRITER.lock().color()

src/usr/editor.rs

@@ -1,7 +1,7 @@
 use crate::api::console::Style;
 use crate::api::process::ExitCode;
 use crate::api::{console, fs, io};
-use crate::sys;
+use crate::api;
 
 use alloc::format;
 use alloc::string::{String, ToString};
@@ -581,11 +581,11 @@ impl Editor {
     }
 
     fn rows(&self) -> usize {
-        sys::console::rows() - 1 // Leave out one line for status line
+        api::console::rows() - 1 // Leave out one line for status line
     }
 
     fn cols(&self) -> usize {
-        sys::console::cols()
+        api::console::cols()
     }
 }
 

src/usr/life.rs

@@ -1,8 +1,8 @@
+use crate::{api, sys};
 use crate::api::console::Style;
 use crate::api::fs;
 use crate::api::process::ExitCode;
 use crate::api::random;
-use crate::sys;
 use crate::sys::console;
 
 use alloc::collections::BTreeSet;
@@ -13,8 +13,8 @@ use alloc::vec::Vec;
 use core::fmt;
 
 struct Game {
-    cols: i64,
-    rows: i64,
+    cols: usize,
+    rows: usize,
     grid: BTreeSet<(i64, i64)>,
     step: usize,
     speed: f64,
@@ -24,7 +24,7 @@ struct Game {
 }
 
 impl Game {
-    pub fn new(cols: i64, rows: i64) -> Self {
+    pub fn new(cols: usize, rows: usize) -> Self {
         Self {
             cols,
             rows,
@@ -74,7 +74,7 @@ impl Game {
             let mut cells_to_remove = vec![];
             for x in 0..self.cols {
                 for y in 0..self.rows {
-                    let cell = (x, y);
+                    let cell = (x as i64, y as i64);
                     let n = neighboors(&cell).iter().fold(0, |s, c|
                         s + self.grid.contains(c) as u8
                     );
@@ -144,7 +144,7 @@ impl fmt::Display for Game {
         let mut out = String::new();
         for y in 0..self.rows {
             for x in 0..self.cols {
-                out.push(if self.grid.contains(&(x, y)) {
+                out.push(if self.grid.contains(&(x as i64, y as i64)) {
                     '#'
                 } else {
                     ' '
@@ -170,7 +170,7 @@ impl fmt::Display for Game {
 }
 
 pub fn main(args: &[&str]) -> Result<(), ExitCode> {
-    let mut game = Game::new(80, 24);
+    let mut game = Game::new(api::console::cols(), api::console::rows() - 1);
     let mut i = 0;
     let n = args.len();
     while i < n {