diff options
Diffstat (limited to 'third_party/rust/bytes/src/buf/buf_mut.rs')
| -rw-r--r-- | third_party/rust/bytes/src/buf/buf_mut.rs | 1493 |
1 files changed, 1493 insertions, 0 deletions
diff --git a/third_party/rust/bytes/src/buf/buf_mut.rs b/third_party/rust/bytes/src/buf/buf_mut.rs new file mode 100644 index 0000000000..685fcc76b1 --- /dev/null +++ b/third_party/rust/bytes/src/buf/buf_mut.rs @@ -0,0 +1,1493 @@ +use crate::buf::{limit, Chain, Limit, UninitSlice}; +#[cfg(feature = "std")] +use crate::buf::{writer, Writer}; + +use core::{cmp, mem, ptr, usize}; + +use alloc::{boxed::Box, vec::Vec}; + +/// A trait for values that provide sequential write access to bytes. +/// +/// Write bytes to a buffer +/// +/// A buffer stores bytes in memory such that write operations are infallible. +/// The underlying storage may or may not be in contiguous memory. A `BufMut` +/// value is a cursor into the buffer. Writing to `BufMut` advances the cursor +/// position. +/// +/// The simplest `BufMut` is a `Vec<u8>`. +/// +/// ``` +/// use bytes::BufMut; +/// +/// let mut buf = vec![]; +/// +/// buf.put(&b"hello world"[..]); +/// +/// assert_eq!(buf, b"hello world"); +/// ``` +pub unsafe trait BufMut { + /// Returns the number of bytes that can be written from the current + /// position until the end of the buffer is reached. + /// + /// This value is greater than or equal to the length of the slice returned + /// by `chunk_mut()`. + /// + /// Writing to a `BufMut` may involve allocating more memory on the fly. + /// Implementations may fail before reaching the number of bytes indicated + /// by this method if they encounter an allocation failure. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut dst = [0; 10]; + /// let mut buf = &mut dst[..]; + /// + /// let original_remaining = buf.remaining_mut(); + /// buf.put(&b"hello"[..]); + /// + /// assert_eq!(original_remaining - 5, buf.remaining_mut()); + /// ``` + /// + /// # Implementer notes + /// + /// Implementations of `remaining_mut` should ensure that the return value + /// does not change unless a call is made to `advance_mut` or any other + /// function that is documented to change the `BufMut`'s current position. + /// + /// # Note + /// + /// `remaining_mut` may return value smaller than actual available space. + fn remaining_mut(&self) -> usize; + + /// Advance the internal cursor of the BufMut + /// + /// The next call to `chunk_mut` will return a slice starting `cnt` bytes + /// further into the underlying buffer. + /// + /// This function is unsafe because there is no guarantee that the bytes + /// being advanced past have been initialized. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = Vec::with_capacity(16); + /// + /// // Write some data + /// buf.chunk_mut()[0..2].copy_from_slice(b"he"); + /// unsafe { buf.advance_mut(2) }; + /// + /// // write more bytes + /// buf.chunk_mut()[0..3].copy_from_slice(b"llo"); + /// + /// unsafe { buf.advance_mut(3); } + /// + /// assert_eq!(5, buf.len()); + /// assert_eq!(buf, b"hello"); + /// ``` + /// + /// # Panics + /// + /// This function **may** panic if `cnt > self.remaining_mut()`. + /// + /// # Implementer notes + /// + /// It is recommended for implementations of `advance_mut` to panic if + /// `cnt > self.remaining_mut()`. If the implementation does not panic, + /// the call must behave as if `cnt == self.remaining_mut()`. + /// + /// A call with `cnt == 0` should never panic and be a no-op. + unsafe fn advance_mut(&mut self, cnt: usize); + + /// Returns true if there is space in `self` for more bytes. + /// + /// This is equivalent to `self.remaining_mut() != 0`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut dst = [0; 5]; + /// let mut buf = &mut dst[..]; + /// + /// assert!(buf.has_remaining_mut()); + /// + /// buf.put(&b"hello"[..]); + /// + /// assert!(!buf.has_remaining_mut()); + /// ``` + fn has_remaining_mut(&self) -> bool { + self.remaining_mut() > 0 + } + + /// Returns a mutable slice starting at the current BufMut position and of + /// length between 0 and `BufMut::remaining_mut()`. Note that this *can* be shorter than the + /// whole remainder of the buffer (this allows non-continuous implementation). + /// + /// This is a lower level function. Most operations are done with other + /// functions. + /// + /// The returned byte slice may represent uninitialized memory. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = Vec::with_capacity(16); + /// + /// unsafe { + /// // MaybeUninit::as_mut_ptr + /// buf.chunk_mut()[0..].as_mut_ptr().write(b'h'); + /// buf.chunk_mut()[1..].as_mut_ptr().write(b'e'); + /// + /// buf.advance_mut(2); + /// + /// buf.chunk_mut()[0..].as_mut_ptr().write(b'l'); + /// buf.chunk_mut()[1..].as_mut_ptr().write(b'l'); + /// buf.chunk_mut()[2..].as_mut_ptr().write(b'o'); + /// + /// buf.advance_mut(3); + /// } + /// + /// assert_eq!(5, buf.len()); + /// assert_eq!(buf, b"hello"); + /// ``` + /// + /// # Implementer notes + /// + /// This function should never panic. `chunk_mut` should return an empty + /// slice **if and only if** `remaining_mut()` returns 0. In other words, + /// `chunk_mut()` returning an empty slice implies that `remaining_mut()` will + /// return 0 and `remaining_mut()` returning 0 implies that `chunk_mut()` will + /// return an empty slice. + /// + /// This function may trigger an out-of-memory abort if it tries to allocate + /// memory and fails to do so. + // The `chunk_mut` method was previously called `bytes_mut`. This alias makes the + // rename more easily discoverable. + #[cfg_attr(docsrs, doc(alias = "bytes_mut"))] + fn chunk_mut(&mut self) -> &mut UninitSlice; + + /// Transfer bytes into `self` from `src` and advance the cursor by the + /// number of bytes written. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// + /// buf.put_u8(b'h'); + /// buf.put(&b"ello"[..]); + /// buf.put(&b" world"[..]); + /// + /// assert_eq!(buf, b"hello world"); + /// ``` + /// + /// # Panics + /// + /// Panics if `self` does not have enough capacity to contain `src`. + fn put<T: super::Buf>(&mut self, mut src: T) + where + Self: Sized, + { + assert!(self.remaining_mut() >= src.remaining()); + + while src.has_remaining() { + let l; + + unsafe { + let s = src.chunk(); + let d = self.chunk_mut(); + l = cmp::min(s.len(), d.len()); + + ptr::copy_nonoverlapping(s.as_ptr(), d.as_mut_ptr() as *mut u8, l); + } + + src.advance(l); + unsafe { + self.advance_mut(l); + } + } + } + + /// Transfer bytes into `self` from `src` and advance the cursor by the + /// number of bytes written. + /// + /// `self` must have enough remaining capacity to contain all of `src`. + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut dst = [0; 6]; + /// + /// { + /// let mut buf = &mut dst[..]; + /// buf.put_slice(b"hello"); + /// + /// assert_eq!(1, buf.remaining_mut()); + /// } + /// + /// assert_eq!(b"hello\0", &dst); + /// ``` + fn put_slice(&mut self, src: &[u8]) { + let mut off = 0; + + assert!( + self.remaining_mut() >= src.len(), + "buffer overflow; remaining = {}; src = {}", + self.remaining_mut(), + src.len() + ); + + while off < src.len() { + let cnt; + + unsafe { + let dst = self.chunk_mut(); + cnt = cmp::min(dst.len(), src.len() - off); + + ptr::copy_nonoverlapping(src[off..].as_ptr(), dst.as_mut_ptr() as *mut u8, cnt); + + off += cnt; + } + + unsafe { + self.advance_mut(cnt); + } + } + } + + /// Put `cnt` bytes `val` into `self`. + /// + /// Logically equivalent to calling `self.put_u8(val)` `cnt` times, but may work faster. + /// + /// `self` must have at least `cnt` remaining capacity. + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut dst = [0; 6]; + /// + /// { + /// let mut buf = &mut dst[..]; + /// buf.put_bytes(b'a', 4); + /// + /// assert_eq!(2, buf.remaining_mut()); + /// } + /// + /// assert_eq!(b"aaaa\0\0", &dst); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_bytes(&mut self, val: u8, cnt: usize) { + for _ in 0..cnt { + self.put_u8(val); + } + } + + /// Writes an unsigned 8 bit integer to `self`. + /// + /// The current position is advanced by 1. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u8(0x01); + /// assert_eq!(buf, b"\x01"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u8(&mut self, n: u8) { + let src = [n]; + self.put_slice(&src); + } + + /// Writes a signed 8 bit integer to `self`. + /// + /// The current position is advanced by 1. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i8(0x01); + /// assert_eq!(buf, b"\x01"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i8(&mut self, n: i8) { + let src = [n as u8]; + self.put_slice(&src) + } + + /// Writes an unsigned 16 bit integer to `self` in big-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u16(0x0809); + /// assert_eq!(buf, b"\x08\x09"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u16(&mut self, n: u16) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes an unsigned 16 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u16_le(0x0809); + /// assert_eq!(buf, b"\x09\x08"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u16_le(&mut self, n: u16) { + self.put_slice(&n.to_le_bytes()) + } + + /// Writes an unsigned 16 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u16_ne(0x0809); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x08\x09"); + /// } else { + /// assert_eq!(buf, b"\x09\x08"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u16_ne(&mut self, n: u16) { + self.put_slice(&n.to_ne_bytes()) + } + + /// Writes a signed 16 bit integer to `self` in big-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i16(0x0809); + /// assert_eq!(buf, b"\x08\x09"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i16(&mut self, n: i16) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes a signed 16 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i16_le(0x0809); + /// assert_eq!(buf, b"\x09\x08"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i16_le(&mut self, n: i16) { + self.put_slice(&n.to_le_bytes()) + } + + /// Writes a signed 16 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i16_ne(0x0809); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x08\x09"); + /// } else { + /// assert_eq!(buf, b"\x09\x08"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i16_ne(&mut self, n: i16) { + self.put_slice(&n.to_ne_bytes()) + } + + /// Writes an unsigned 32 bit integer to `self` in big-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u32(0x0809A0A1); + /// assert_eq!(buf, b"\x08\x09\xA0\xA1"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u32(&mut self, n: u32) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes an unsigned 32 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u32_le(0x0809A0A1); + /// assert_eq!(buf, b"\xA1\xA0\x09\x08"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u32_le(&mut self, n: u32) { + self.put_slice(&n.to_le_bytes()) + } + + /// Writes an unsigned 32 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u32_ne(0x0809A0A1); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x08\x09\xA0\xA1"); + /// } else { + /// assert_eq!(buf, b"\xA1\xA0\x09\x08"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u32_ne(&mut self, n: u32) { + self.put_slice(&n.to_ne_bytes()) + } + + /// Writes a signed 32 bit integer to `self` in big-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i32(0x0809A0A1); + /// assert_eq!(buf, b"\x08\x09\xA0\xA1"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i32(&mut self, n: i32) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes a signed 32 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i32_le(0x0809A0A1); + /// assert_eq!(buf, b"\xA1\xA0\x09\x08"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i32_le(&mut self, n: i32) { + self.put_slice(&n.to_le_bytes()) + } + + /// Writes a signed 32 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i32_ne(0x0809A0A1); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x08\x09\xA0\xA1"); + /// } else { + /// assert_eq!(buf, b"\xA1\xA0\x09\x08"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i32_ne(&mut self, n: i32) { + self.put_slice(&n.to_ne_bytes()) + } + + /// Writes an unsigned 64 bit integer to `self` in the big-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u64(0x0102030405060708); + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u64(&mut self, n: u64) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes an unsigned 64 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u64_le(0x0102030405060708); + /// assert_eq!(buf, b"\x08\x07\x06\x05\x04\x03\x02\x01"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u64_le(&mut self, n: u64) { + self.put_slice(&n.to_le_bytes()) + } + + /// Writes an unsigned 64 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u64_ne(0x0102030405060708); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08"); + /// } else { + /// assert_eq!(buf, b"\x08\x07\x06\x05\x04\x03\x02\x01"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u64_ne(&mut self, n: u64) { + self.put_slice(&n.to_ne_bytes()) + } + + /// Writes a signed 64 bit integer to `self` in the big-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i64(0x0102030405060708); + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i64(&mut self, n: i64) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes a signed 64 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i64_le(0x0102030405060708); + /// assert_eq!(buf, b"\x08\x07\x06\x05\x04\x03\x02\x01"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i64_le(&mut self, n: i64) { + self.put_slice(&n.to_le_bytes()) + } + + /// Writes a signed 64 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i64_ne(0x0102030405060708); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08"); + /// } else { + /// assert_eq!(buf, b"\x08\x07\x06\x05\x04\x03\x02\x01"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i64_ne(&mut self, n: i64) { + self.put_slice(&n.to_ne_bytes()) + } + + /// Writes an unsigned 128 bit integer to `self` in the big-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u128(0x01020304050607080910111213141516); + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u128(&mut self, n: u128) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes an unsigned 128 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u128_le(0x01020304050607080910111213141516); + /// assert_eq!(buf, b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u128_le(&mut self, n: u128) { + self.put_slice(&n.to_le_bytes()) + } + + /// Writes an unsigned 128 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u128_ne(0x01020304050607080910111213141516); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16"); + /// } else { + /// assert_eq!(buf, b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u128_ne(&mut self, n: u128) { + self.put_slice(&n.to_ne_bytes()) + } + + /// Writes a signed 128 bit integer to `self` in the big-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i128(0x01020304050607080910111213141516); + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i128(&mut self, n: i128) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes a signed 128 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i128_le(0x01020304050607080910111213141516); + /// assert_eq!(buf, b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i128_le(&mut self, n: i128) { + self.put_slice(&n.to_le_bytes()) + } + + /// Writes a signed 128 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i128_ne(0x01020304050607080910111213141516); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16"); + /// } else { + /// assert_eq!(buf, b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i128_ne(&mut self, n: i128) { + self.put_slice(&n.to_ne_bytes()) + } + + /// Writes an unsigned n-byte integer to `self` in big-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_uint(0x010203, 3); + /// assert_eq!(buf, b"\x01\x02\x03"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_uint(&mut self, n: u64, nbytes: usize) { + self.put_slice(&n.to_be_bytes()[mem::size_of_val(&n) - nbytes..]); + } + + /// Writes an unsigned n-byte integer to `self` in the little-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_uint_le(0x010203, 3); + /// assert_eq!(buf, b"\x03\x02\x01"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_uint_le(&mut self, n: u64, nbytes: usize) { + self.put_slice(&n.to_le_bytes()[0..nbytes]); + } + + /// Writes an unsigned n-byte integer to `self` in the native-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_uint_ne(0x010203, 3); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x01\x02\x03"); + /// } else { + /// assert_eq!(buf, b"\x03\x02\x01"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_uint_ne(&mut self, n: u64, nbytes: usize) { + if cfg!(target_endian = "big") { + self.put_uint(n, nbytes) + } else { + self.put_uint_le(n, nbytes) + } + } + + /// Writes low `nbytes` of a signed integer to `self` in big-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_int(0x0504010203, 3); + /// assert_eq!(buf, b"\x01\x02\x03"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self` or if `nbytes` is greater than 8. + fn put_int(&mut self, n: i64, nbytes: usize) { + self.put_slice(&n.to_be_bytes()[mem::size_of_val(&n) - nbytes..]); + } + + /// Writes low `nbytes` of a signed integer to `self` in little-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_int_le(0x0504010203, 3); + /// assert_eq!(buf, b"\x03\x02\x01"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self` or if `nbytes` is greater than 8. + fn put_int_le(&mut self, n: i64, nbytes: usize) { + self.put_slice(&n.to_le_bytes()[0..nbytes]); + } + + /// Writes low `nbytes` of a signed integer to `self` in native-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_int_ne(0x010203, 3); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x01\x02\x03"); + /// } else { + /// assert_eq!(buf, b"\x03\x02\x01"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self` or if `nbytes` is greater than 8. + fn put_int_ne(&mut self, n: i64, nbytes: usize) { + if cfg!(target_endian = "big") { + self.put_int(n, nbytes) + } else { + self.put_int_le(n, nbytes) + } + } + + /// Writes an IEEE754 single-precision (4 bytes) floating point number to + /// `self` in big-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_f32(1.2f32); + /// assert_eq!(buf, b"\x3F\x99\x99\x9A"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_f32(&mut self, n: f32) { + self.put_u32(n.to_bits()); + } + + /// Writes an IEEE754 single-precision (4 bytes) floating point number to + /// `self` in little-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_f32_le(1.2f32); + /// assert_eq!(buf, b"\x9A\x99\x99\x3F"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_f32_le(&mut self, n: f32) { + self.put_u32_le(n.to_bits()); + } + + /// Writes an IEEE754 single-precision (4 bytes) floating point number to + /// `self` in native-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_f32_ne(1.2f32); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x3F\x99\x99\x9A"); + /// } else { + /// assert_eq!(buf, b"\x9A\x99\x99\x3F"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_f32_ne(&mut self, n: f32) { + self.put_u32_ne(n.to_bits()); + } + + /// Writes an IEEE754 double-precision (8 bytes) floating point number to + /// `self` in big-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_f64(1.2f64); + /// assert_eq!(buf, b"\x3F\xF3\x33\x33\x33\x33\x33\x33"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_f64(&mut self, n: f64) { + self.put_u64(n.to_bits()); + } + + /// Writes an IEEE754 double-precision (8 bytes) floating point number to + /// `self` in little-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_f64_le(1.2f64); + /// assert_eq!(buf, b"\x33\x33\x33\x33\x33\x33\xF3\x3F"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_f64_le(&mut self, n: f64) { + self.put_u64_le(n.to_bits()); + } + + /// Writes an IEEE754 double-precision (8 bytes) floating point number to + /// `self` in native-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_f64_ne(1.2f64); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x3F\xF3\x33\x33\x33\x33\x33\x33"); + /// } else { + /// assert_eq!(buf, b"\x33\x33\x33\x33\x33\x33\xF3\x3F"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_f64_ne(&mut self, n: f64) { + self.put_u64_ne(n.to_bits()); + } + + /// Creates an adaptor which can write at most `limit` bytes to `self`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let arr = &mut [0u8; 128][..]; + /// assert_eq!(arr.remaining_mut(), 128); + /// + /// let dst = arr.limit(10); + /// assert_eq!(dst.remaining_mut(), 10); + /// ``` + fn limit(self, limit: usize) -> Limit<Self> + where + Self: Sized, + { + limit::new(self, limit) + } + + /// Creates an adaptor which implements the `Write` trait for `self`. + /// + /// This function returns a new value which implements `Write` by adapting + /// the `Write` trait functions to the `BufMut` trait functions. Given that + /// `BufMut` operations are infallible, none of the `Write` functions will + /// return with `Err`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// use std::io::Write; + /// + /// let mut buf = vec![].writer(); + /// + /// let num = buf.write(&b"hello world"[..]).unwrap(); + /// assert_eq!(11, num); + /// + /// let buf = buf.into_inner(); + /// + /// assert_eq!(*buf, b"hello world"[..]); + /// ``` + #[cfg(feature = "std")] + #[cfg_attr(docsrs, doc(cfg(feature = "std")))] + fn writer(self) -> Writer<Self> + where + Self: Sized, + { + writer::new(self) + } + + /// Creates an adapter which will chain this buffer with another. + /// + /// The returned `BufMut` instance will first write to all bytes from + /// `self`. Afterwards, it will write to `next`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut a = [0u8; 5]; + /// let mut b = [0u8; 6]; + /// + /// let mut chain = (&mut a[..]).chain_mut(&mut b[..]); + /// + /// chain.put_slice(b"hello world"); + /// + /// assert_eq!(&a[..], b"hello"); + /// assert_eq!(&b[..], b" world"); + /// ``` + fn chain_mut<U: BufMut>(self, next: U) -> Chain<Self, U> + where + Self: Sized, + { + Chain::new(self, next) + } +} + +macro_rules! deref_forward_bufmut { + () => { + fn remaining_mut(&self) -> usize { + (**self).remaining_mut() + } + + fn chunk_mut(&mut self) -> &mut UninitSlice { + (**self).chunk_mut() + } + + unsafe fn advance_mut(&mut self, cnt: usize) { + (**self).advance_mut(cnt) + } + + fn put_slice(&mut self, src: &[u8]) { + (**self).put_slice(src) + } + + fn put_u8(&mut self, n: u8) { + (**self).put_u8(n) + } + + fn put_i8(&mut self, n: i8) { + (**self).put_i8(n) + } + + fn put_u16(&mut self, n: u16) { + (**self).put_u16(n) + } + + fn put_u16_le(&mut self, n: u16) { + (**self).put_u16_le(n) + } + + fn put_u16_ne(&mut self, n: u16) { + (**self).put_u16_ne(n) + } + + fn put_i16(&mut self, n: i16) { + (**self).put_i16(n) + } + + fn put_i16_le(&mut self, n: i16) { + (**self).put_i16_le(n) + } + + fn put_i16_ne(&mut self, n: i16) { + (**self).put_i16_ne(n) + } + + fn put_u32(&mut self, n: u32) { + (**self).put_u32(n) + } + + fn put_u32_le(&mut self, n: u32) { + (**self).put_u32_le(n) + } + + fn put_u32_ne(&mut self, n: u32) { + (**self).put_u32_ne(n) + } + + fn put_i32(&mut self, n: i32) { + (**self).put_i32(n) + } + + fn put_i32_le(&mut self, n: i32) { + (**self).put_i32_le(n) + } + + fn put_i32_ne(&mut self, n: i32) { + (**self).put_i32_ne(n) + } + + fn put_u64(&mut self, n: u64) { + (**self).put_u64(n) + } + + fn put_u64_le(&mut self, n: u64) { + (**self).put_u64_le(n) + } + + fn put_u64_ne(&mut self, n: u64) { + (**self).put_u64_ne(n) + } + + fn put_i64(&mut self, n: i64) { + (**self).put_i64(n) + } + + fn put_i64_le(&mut self, n: i64) { + (**self).put_i64_le(n) + } + + fn put_i64_ne(&mut self, n: i64) { + (**self).put_i64_ne(n) + } + }; +} + +unsafe impl<T: BufMut + ?Sized> BufMut for &mut T { + deref_forward_bufmut!(); +} + +unsafe impl<T: BufMut + ?Sized> BufMut for Box<T> { + deref_forward_bufmut!(); +} + +unsafe impl BufMut for &mut [u8] { + #[inline] + fn remaining_mut(&self) -> usize { + self.len() + } + + #[inline] + fn chunk_mut(&mut self) -> &mut UninitSlice { + // UninitSlice is repr(transparent), so safe to transmute + unsafe { &mut *(*self as *mut [u8] as *mut _) } + } + + #[inline] + unsafe fn advance_mut(&mut self, cnt: usize) { + // Lifetime dance taken from `impl Write for &mut [u8]`. + let (_, b) = core::mem::replace(self, &mut []).split_at_mut(cnt); + *self = b; + } + + #[inline] + fn put_slice(&mut self, src: &[u8]) { + self[..src.len()].copy_from_slice(src); + unsafe { + self.advance_mut(src.len()); + } + } + + fn put_bytes(&mut self, val: u8, cnt: usize) { + assert!(self.remaining_mut() >= cnt); + unsafe { + ptr::write_bytes(self.as_mut_ptr(), val, cnt); + self.advance_mut(cnt); + } + } +} + +unsafe impl BufMut for Vec<u8> { + #[inline] + fn remaining_mut(&self) -> usize { + // A vector can never have more than isize::MAX bytes + core::isize::MAX as usize - self.len() + } + + #[inline] + unsafe fn advance_mut(&mut self, cnt: usize) { + let len = self.len(); + let remaining = self.capacity() - len; + + assert!( + cnt <= remaining, + "cannot advance past `remaining_mut`: {:?} <= {:?}", + cnt, + remaining + ); + + self.set_len(len + cnt); + } + + #[inline] + fn chunk_mut(&mut self) -> &mut UninitSlice { + if self.capacity() == self.len() { + self.reserve(64); // Grow the vec + } + + let cap = self.capacity(); + let len = self.len(); + + let ptr = self.as_mut_ptr(); + unsafe { &mut UninitSlice::from_raw_parts_mut(ptr, cap)[len..] } + } + + // Specialize these methods so they can skip checking `remaining_mut` + // and `advance_mut`. + fn put<T: super::Buf>(&mut self, mut src: T) + where + Self: Sized, + { + // In case the src isn't contiguous, reserve upfront + self.reserve(src.remaining()); + + while src.has_remaining() { + let l; + + // a block to contain the src.bytes() borrow + { + let s = src.chunk(); + l = s.len(); + self.extend_from_slice(s); + } + + src.advance(l); + } + } + + #[inline] + fn put_slice(&mut self, src: &[u8]) { + self.extend_from_slice(src); + } + + fn put_bytes(&mut self, val: u8, cnt: usize) { + let new_len = self.len().checked_add(cnt).unwrap(); + self.resize(new_len, val); + } +} + +// The existence of this function makes the compiler catch if the BufMut +// trait is "object-safe" or not. +fn _assert_trait_object(_b: &dyn BufMut) {} |