fix pi-lens warnings: unwraps, shell SC2046, dup code (fmtbuf/scripts/hexdump/cat/ahci/pci)

- memory.rs: self-test Layout::from_size_align no longer panics — the
  test fails cleanly on an invalid layout
- fat.rs: v() no longer unwraps the active-volume slot — invariant
  violation logs + halts instead of panicking mid-disk-io
- strbuf: shared FmtBuf replaces the duplicated PanicBuf/FmtBuf
  (main.rs + sched.rs)
- test-disk.sh: SC2046 — conditional --fresh arg no longer relies on
  word splitting
- scripts: boot.sh/boot-image.sh share lib-boot-args.sh (dup args loop)
- shell: cat/hexdump stdin pairs unified with Option<&str> marker;
  hexdump format_row folded into format_partial
- ahci: read/write_sectors unified behind dma_sectors
- pci: config_read/write share config_addr

1 files changed, 21 insertions, 73 deletions

diff --git a/shell/src/lib.rs b/shell/src/lib.rs
index 617e5a4..4640697 100644
--- a/shell/src/lib.rs
+++ b/shell/src/lib.rs
@@ -515,7 +515,12 @@ impl Pipeline {
                     }
                 }
                 Filter::Pause => {
-                    let StageState::Pause { shown, screen, cols } = st else {
+                    let StageState::Pause {
+                        shown,
+                        screen,
+                        cols,
+                    } = st
+                    else {
                         unreachable!("stage state does not match filter")
                     };
                     for l in cur.drain(..) {
@@ -871,7 +876,7 @@ fn cmd_cat(p: &Parsed) {
             if p.args.is_empty() {
                 // Path-less `cat` with no input keyword reads the keyboard
                 // until ^D.
-                cat_stdin(&mut pipe);
+                cat_stdin(&mut pipe, None);
             } else {
                 for path in &p.args {
                     if !cat_file(&mut pipe, path) {
@@ -885,7 +890,7 @@ fn cmd_cat(p: &Parsed) {
         }
         Input::Til(marker) => {
             if p.args.is_empty() {
-                cat_stdin_until(&mut pipe, marker);
+                cat_stdin(&mut pipe, Some(marker));
             } else {
                 // `cat <path> TIL <marker>` — the paths are the input
                 // source, truncated at the first marker line.
@@ -904,34 +909,21 @@ fn cmd_cat(p: &Parsed) {
     pipe.end();
 }
 
-fn cat_stdin(pipe: &mut Pipeline) -> bool {
+/// Read lines from the tty until ^C/^D (or an exact marker line, when
+/// `marker` is Some — the marker itself is not part of the input).
+fn cat_stdin(pipe: &mut Pipeline, marker: Option<&str>) -> bool {
     loop {
         match tty::read_line() {
             LineInput::Line(l) => {
-                if !pipe.line(l.as_str()) {
-                    return false;
-                }
-            }
-            LineInput::Interrupted => return false, // ^C aborts the stream
-            LineInput::Eof => return true,          // ^D = EOF
-        }
-    }
-}
-
-fn cat_stdin_until(pipe: &mut Pipeline, marker: &str) -> bool {
-    loop {
-        match tty::read_line() {
-            LineInput::Line(l) => {
-                // Marker line is not part of the input.
-                if l.as_str() == marker {
+                if marker.is_some() && l.as_str() == marker.unwrap() {
                     return true;
                 }
                 if !pipe.line(l.as_str()) {
                     return false;
                 }
             }
-            LineInput::Interrupted => return false,
-            LineInput::Eof => return true,
+            LineInput::Interrupted => return false, // ^C aborts the stream
+            LineInput::Eof => return true,          // ^D = EOF
         }
     }
 }
@@ -1030,25 +1022,6 @@ struct HexCtx<'a> {
     alive: bool,
 }
 
-fn format_row(addr: u64, row: &[u8; 16]) -> String {
-    let mut out = String::new();
-    use core::fmt::Write as _;
-    let _ = core::write!(out, "{:08x}  ", addr);
-    for &b in row {
-        let _ = core::write!(out, "{:02x} ", b);
-    }
-    out.push_str(" |");
-    for &b in row {
-        out.push(if b.is_ascii_graphic() || b == b' ' {
-            b as char
-        } else {
-            '.'
-        });
-    }
-    out.push('|');
-    out
-}
-
 fn format_partial(addr: u64, row: &[u8]) -> String {
     let mut out = String::new();
     use core::fmt::Write as _;
@@ -1081,7 +1054,7 @@ impl HexCtx<'_> {
             self.row[self.row_len] = b;
             self.row_len += 1;
             if self.row_len == 16 {
-                let line = format_row(self.pos, &self.row);
+                let line = format_partial(self.pos, &self.row);
                 self.alive = self.pipe.line(&line);
                 self.pos += 16;
                 self.row_len = 0;
@@ -1106,7 +1079,7 @@ fn cmd_hexdump(p: &Parsed) {
     match &p.input {
         Input::None => {
             if p.args.is_empty() {
-                hexdump_stdin(&mut pipe);
+                hexdump_stdin(&mut pipe, None);
             } else {
                 for path in &p.args {
                     if !hexdump_file(&mut pipe, path) {
@@ -1120,7 +1093,7 @@ fn cmd_hexdump(p: &Parsed) {
         }
         Input::Til(marker) => {
             if p.args.is_empty() {
-                hexdump_stdin_until(&mut pipe, marker);
+                hexdump_stdin(&mut pipe, Some(marker));
             } else {
                 // `hexdump <path> TIL <marker>` — the paths are the input
                 // source, truncated at the first marker line.
@@ -1176,34 +1149,9 @@ fn hexdump_file(pipe: &mut Pipeline, path: &str) -> bool {
     ctx.alive
 }
 
-fn hexdump_stdin(pipe: &mut Pipeline) {
-    let mut ctx = HexCtx {
-        pipe,
-        pos: 0,
-        row: [0u8; 16],
-        row_len: 0,
-        alive: true,
-    };
-    loop {
-        match tty::read_line() {
-            LineInput::Line(l) => {
-                ctx.feed(l.as_str().as_bytes());
-                if !ctx.alive {
-                    break;
-                }
-                ctx.feed(b"\n");
-                if !ctx.alive {
-                    break;
-                }
-            }
-            LineInput::Interrupted => break,
-            LineInput::Eof => break,
-        }
-    }
-    ctx.flush();
-}
-
-fn hexdump_stdin_until(pipe: &mut Pipeline, marker: &str) {
+/// Hex-dump lines from the tty until ^C/^D (or an exact marker line,
+/// when `marker` is Some — the marker itself is not dumped).
+fn hexdump_stdin(pipe: &mut Pipeline, marker: Option<&str>) {
     let mut ctx = HexCtx {
         pipe,
         pos: 0,
@@ -1214,7 +1162,7 @@ fn hexdump_stdin_until(pipe: &mut Pipeline, marker: &str) {
     loop {
         match tty::read_line() {
             LineInput::Line(l) => {
-                if l.as_str() == marker {
+                if marker.is_some() && l.as_str() == marker.unwrap() {
                     break;
                 }
                 ctx.feed(l.as_str().as_bytes());