1 files changed, 56 insertions, 0 deletions
diff --git a/src/preview/zero_len_file_view.rs b/src/preview/zero_len_file_view.rs
new file mode 100644
index 0000000..5ec3045
--- /dev/null
+++ b/src/preview/zero_len_file_view.rs
@@ -0,0 +1,56 @@
+use {
+    crate::{
+        display::{CropWriter, SPACE_FILLING, Screen, W},
+        errors::ProgramError,
+        skin::PanelSkin,
+    },
+    char_reader::CharReader,
+    crossterm::{
+        cursor,
+        QueueableCommand,
+    },
+    std::{
+        fs::File,
+        path::PathBuf,
+    },
+    termimad::{Area},
+};
+
+/// a (light) display for a file declaring a size 0,
+/// as happens for many system "files", for example in /proc
+pub struct ZeroLenFileView {
+    path: PathBuf,
+}
+
+impl ZeroLenFileView {
+    pub fn new(path: PathBuf) -> Self {
+        Self {
+            path,
+        }
+    }
+    pub fn display(
+        &mut self,
+        w: &mut W,
+        _screen: Screen,
+        panel_skin: &PanelSkin,
+        area: &Area,
+    ) -> Result<(), ProgramError> {
+        let styles = &panel_skin.styles;
+        let line_count = area.height as usize;
+        let file = File::open(&self.path)?;
+        let mut reader = CharReader::new(file);
+        // line_len here is in chars, and we crop in cols, but it's OK because both
+        // are usually identical for system files and we crop later anyway
+        let line_len = area.width as usize;
+        for y in 0..line_count {
+            w.queue(cursor::MoveTo(area.left, y as u16 + area.top))?;
+            let mut cw = CropWriter::new(w, area.width as usize);
+            let cw = &mut cw;
+            if let Some(line) = reader.next_line(line_len, 15_000)? {
+                cw.queue_str(&styles.default, &line)?;
+            }
+            cw.fill(&styles.default, &SPACE_FILLING)?;
+        }
+        Ok(())
+    }
+}