summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorNick Cameron <nrc@ncameron.org>2022-04-07 15:56:25 +0100
committerNick Cameron <nrc@ncameron.org>2022-05-03 17:52:52 +0100
commita3c30e440a7a2cb36b6d8d405fdf7d5d50110903 (patch)
tree2b712e7a2d570fd049cc08ce019b95451017c801
parent3d237ab52920924694f6fc3e47ee8588514bfa70 (diff)
downloadrust-a3c30e440a7a2cb36b6d8d405fdf7d5d50110903.tar.gz
std::io: Modify some ReadBuf method signatures to return `&mut Self`
This allows using `ReadBuf` in a builder-like style and to setup a `ReadBuf` and pass it to `read_buf` in a single expression, e.g., ``` // With this PR: reader.read_buf(ReadBuf::uninit(buf).assume_init(init_len))?; // Previously: let mut buf = ReadBuf::uninit(buf); buf.assume_init(init_len); reader.read_buf(&mut buf)?; ``` Signed-off-by: Nick Cameron <nrc@ncameron.org>
-rw-r--r--library/std/src/io/readbuf.rs18
1 files changed, 11 insertions, 7 deletions
diff --git a/library/std/src/io/readbuf.rs b/library/std/src/io/readbuf.rs
index c655bc88930..78d1113f837 100644
--- a/library/std/src/io/readbuf.rs
+++ b/library/std/src/io/readbuf.rs
@@ -166,8 +166,8 @@ impl<'a> ReadBuf<'a> {
///
/// The number of initialized bytes is not changed, and the contents of the buffer are not modified.
#[inline]
- pub fn clear(&mut self) {
- self.set_filled(0); // The assertion in `set_filled` is optimized out
+ pub fn clear(&mut self) -> &mut Self {
+ self.set_filled(0) // The assertion in `set_filled` is optimized out
}
/// Increases the size of the filled region of the buffer.
@@ -178,8 +178,8 @@ impl<'a> ReadBuf<'a> {
///
/// Panics if the filled region of the buffer would become larger than the initialized region.
#[inline]
- pub fn add_filled(&mut self, n: usize) {
- self.set_filled(self.filled + n);
+ pub fn add_filled(&mut self, n: usize) -> &mut Self {
+ self.set_filled(self.filled + n)
}
/// Sets the size of the filled region of the buffer.
@@ -193,10 +193,11 @@ impl<'a> ReadBuf<'a> {
///
/// Panics if the filled region of the buffer would become larger than the initialized region.
#[inline]
- pub fn set_filled(&mut self, n: usize) {
+ pub fn set_filled(&mut self, n: usize) -> &mut Self {
assert!(n <= self.initialized);
self.filled = n;
+ self
}
/// Asserts that the first `n` unfilled bytes of the buffer are initialized.
@@ -208,8 +209,9 @@ impl<'a> ReadBuf<'a> {
///
/// The caller must ensure that the first `n` unfilled bytes of the buffer have already been initialized.
#[inline]
- pub unsafe fn assume_init(&mut self, n: usize) {
+ pub unsafe fn assume_init(&mut self, n: usize) -> &mut Self {
self.initialized = cmp::max(self.initialized, self.filled + n);
+ self
}
/// Appends data to the buffer, advancing the written position and possibly also the initialized position.
@@ -227,7 +229,9 @@ impl<'a> ReadBuf<'a> {
}
// SAFETY: We just added the entire contents of buf to the filled section.
- unsafe { self.assume_init(buf.len()) }
+ unsafe {
+ self.assume_init(buf.len());
+ }
self.add_filled(buf.len());
}