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fix(tty): preserve OPOST chars when output is full #1987

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Merged
fslongjin merged 2 commits into from
Jun 25, 2026
+24 −24
Merged

fix(tty): preserve OPOST chars when output is full #1987

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140b043
fix(tty): preserve OPOST chars when output is full
fslongjin Jun 25, 2026
9403d4d
fix(rootfs): provide coreutils true in bin
fslongjin Jun 25, 2026
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46 changes: 23 additions & 23 deletions kernel/src/driver/tty/tty_ldisc/ntty.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -63,6 +63,13 @@ struct EchoStep {
canon_cursor_column: u32,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
enum OpostCharResult {
Emitted,
ConsumedWithoutOutput,
NeedsMoreRoom,
}

impl NTtyLinediscipline {
#[inline]
pub fn disc_data(&self) -> SpinLockGuard<'_, NTtyData> {
Expand Down Expand Up @@ -1487,18 +1494,18 @@ impl NTtyData {
mut c: u8,
out: &mut Vec<u8>,
space: usize,
) -> Result<usize, SystemError> {
) -> OpostCharResult {
let used = out.len();
if used >= space {
return Err(SystemError::ENOBUFS);
return OpostCharResult::NeedsMoreRoom;
}

if c as usize == 8 {
if self.cursor_column > 0 {
self.cursor_column -= 1;
}
out.push(c);
return Ok(1);
return OpostCharResult::Emitted;
}

match c as char {
Expand All @@ -1508,18 +1515,18 @@ impl NTtyData {
}
if termios.output_mode.contains(OutputMode::ONLCR) {
if used + 2 > space {
return Err(SystemError::ENOBUFS);
return OpostCharResult::NeedsMoreRoom;
}
self.cursor_column = 0;
self.canon_cursor_column = 0;
out.extend_from_slice(b"\r\n");
return Ok(2);
return OpostCharResult::Emitted;
}
self.canon_cursor_column = self.cursor_column;
}
'\r' => {
if termios.output_mode.contains(OutputMode::ONOCR) && self.cursor_column == 0 {
return Ok(0);
return OpostCharResult::ConsumedWithoutOutput;
}

if termios.output_mode.contains(OutputMode::OCRNL) {
Expand All @@ -1537,11 +1544,11 @@ impl NTtyData {
let spaces = 8 - (self.cursor_column & 7) as usize;
if output_mode_has_xtabs(termios) {
if used + spaces > space {
return Err(SystemError::ENOBUFS);
return OpostCharResult::NeedsMoreRoom;
}
self.cursor_column += spaces as u32;
out.extend_from_slice(&b" "[..spaces]);
return Ok(spaces);
return OpostCharResult::Emitted;
}
self.cursor_column += spaces as u32;
}
Expand All @@ -1561,7 +1568,7 @@ impl NTtyData {
}

out.push(c);
Ok(1)
OpostCharResult::Emitted
}

fn simple_output_block_len(&self, termios: &Termios, buf: &[u8], limit: usize) -> usize {
Expand Down Expand Up @@ -1921,30 +1928,23 @@ impl TtyLineDiscipline for NTtyLinediscipline {
let mut guard = self.disc_data();
let cursor_column = guard.cursor_column;
let canon_cursor_column = guard.canon_cursor_column;
match guard.process_output_char_to_buf(
let opost_result = guard.process_output_char_to_buf(
&termios,
buf[offset],
&mut out_buf,
space,
) {
Ok(_) => {}
Err(SystemError::ENOBUFS) => {
guard.cursor_column = cursor_column;
guard.canon_cursor_column = canon_cursor_column;
}
Err(err) => {
guard.cursor_column = cursor_column;
guard.canon_cursor_column = canon_cursor_column;
return Err(err);
}
);
if opost_result == OpostCharResult::NeedsMoreRoom {
guard.cursor_column = cursor_column;
guard.canon_cursor_column = canon_cursor_column;
}
drop(guard);

if out_buf.is_empty() {
if opost_result == OpostCharResult::ConsumedWithoutOutput {
offset += 1;
nr -= 1;
made_progress = true;
} else {
} else if opost_result == OpostCharResult::Emitted {
let mut sent = 0;
while sent < out_buf.len() {
let written =
Expand Down
2 changes: 1 addition & 1 deletion user/dadk/config/all/core_utils-9.4.0.toml
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Original file line number Diff line number Diff line change
Expand Up @@ -29,7 +29,7 @@ archive-rootdir = "coreutils-9.4"
# 构建相关信息
[build]
# （可选）构建命令
build-command = "./configure CC=x86_64-linux-musl-gcc CFLAGS=-static && make -j $(nproc) && DESTDIR=$DADK_CURRENT_BUILD_DIR make install"
build-command = "FORCE_UNSAFE_CONFIGURE=1 ./configure CC=x86_64-linux-musl-gcc CFLAGS=-static && make -j $(nproc) && DESTDIR=$DADK_CURRENT_BUILD_DIR make install && install -Dm755 $DADK_CURRENT_BUILD_DIR/usr/local/bin/true $DADK_CURRENT_BUILD_DIR/bin/true && install -Dm755 $DADK_CURRENT_BUILD_DIR/usr/local/bin/false $DADK_CURRENT_BUILD_DIR/bin/false"
# 安装相关信息
[install]
# （可选）安装到DragonOS的路径
Expand Down
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