Adding upstream version 115.7.0esr.upstream/115.7.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 290 insertions, 0 deletions

diff --git a/third_party/rust/itoa/src/lib.rs b/third_party/rust/itoa/src/lib.rs
new file mode 100644
index 0000000000..168407f061
--- /dev/null
+++ b/third_party/rust/itoa/src/lib.rs
@@ -0,0 +1,290 @@
+//! [![github]](https://github.com/dtolnay/itoa) [![crates-io]](https://crates.io/crates/itoa) [![docs-rs]](https://docs.rs/itoa)
+//!
+//! [github]: https://img.shields.io/badge/github-8da0cb?style=for-the-badge&labelColor=555555&logo=github
+//! [crates-io]: https://img.shields.io/badge/crates.io-fc8d62?style=for-the-badge&labelColor=555555&logo=rust
+//! [docs-rs]: https://img.shields.io/badge/docs.rs-66c2a5?style=for-the-badge&labelColor=555555&logo=docs.rs
+//!
+//! <br>
+//!
+//! This crate provides a fast conversion of integer primitives to decimal
+//! strings. The implementation comes straight from [libcore] but avoids the
+//! performance penalty of going through [`core::fmt::Formatter`].
+//!
+//! See also [`ryu`] for printing floating point primitives.
+//!
+//! [libcore]: https://github.com/rust-lang/rust/blob/b8214dc6c6fc20d0a660fb5700dca9ebf51ebe89/src/libcore/fmt/num.rs#L201-L254
+//! [`core::fmt::Formatter`]: https://doc.rust-lang.org/std/fmt/struct.Formatter.html
+//! [`ryu`]: https://github.com/dtolnay/ryu
+//!
+//! # Example
+//!
+//! ```
+//! fn main() {
+//!     let mut buffer = itoa::Buffer::new();
+//!     let printed = buffer.format(128u64);
+//!     assert_eq!(printed, "128");
+//! }
+//! ```
+//!
+//! # Performance (lower is better)
+//!
+//! ![performance](https://raw.githubusercontent.com/dtolnay/itoa/master/performance.png)
+
+#![doc(html_root_url = "https://docs.rs/itoa/1.0.5")]
+#![no_std]
+#![allow(
+    clippy::cast_lossless,
+    clippy::cast_possible_truncation,
+    clippy::must_use_candidate,
+    clippy::unreadable_literal
+)]
+
+mod udiv128;
+
+use core::mem::{self, MaybeUninit};
+use core::{ptr, slice, str};
+#[cfg(feature = "no-panic")]
+use no_panic::no_panic;
+
+/// A correctly sized stack allocation for the formatted integer to be written
+/// into.
+///
+/// # Example
+///
+/// ```
+/// let mut buffer = itoa::Buffer::new();
+/// let printed = buffer.format(1234);
+/// assert_eq!(printed, "1234");
+/// ```
+pub struct Buffer {
+    bytes: [MaybeUninit<u8>; I128_MAX_LEN],
+}
+
+impl Default for Buffer {
+    #[inline]
+    fn default() -> Buffer {
+        Buffer::new()
+    }
+}
+
+impl Clone for Buffer {
+    #[inline]
+    fn clone(&self) -> Self {
+        Buffer::new()
+    }
+}
+
+impl Buffer {
+    /// This is a cheap operation; you don't need to worry about reusing buffers
+    /// for efficiency.
+    #[inline]
+    #[cfg_attr(feature = "no-panic", no_panic)]
+    pub fn new() -> Buffer {
+        let bytes = [MaybeUninit::<u8>::uninit(); I128_MAX_LEN];
+        Buffer { bytes }
+    }
+
+    /// Print an integer into this buffer and return a reference to its string
+    /// representation within the buffer.
+    #[cfg_attr(feature = "no-panic", no_panic)]
+    pub fn format<I: Integer>(&mut self, i: I) -> &str {
+        i.write(unsafe {
+            &mut *(&mut self.bytes as *mut [MaybeUninit<u8>; I128_MAX_LEN]
+                as *mut <I as private::Sealed>::Buffer)
+        })
+    }
+}
+
+/// An integer that can be written into an [`itoa::Buffer`][Buffer].
+///
+/// This trait is sealed and cannot be implemented for types outside of itoa.
+pub trait Integer: private::Sealed {}
+
+// Seal to prevent downstream implementations of the Integer trait.
+mod private {
+    pub trait Sealed: Copy {
+        type Buffer: 'static;
+        fn write(self, buf: &mut Self::Buffer) -> &str;
+    }
+}
+
+const DEC_DIGITS_LUT: &[u8] = b"\
+      0001020304050607080910111213141516171819\
+      2021222324252627282930313233343536373839\
+      4041424344454647484950515253545556575859\
+      6061626364656667686970717273747576777879\
+      8081828384858687888990919293949596979899";
+
+// Adaptation of the original implementation at
+// https://github.com/rust-lang/rust/blob/b8214dc6c6fc20d0a660fb5700dca9ebf51ebe89/src/libcore/fmt/num.rs#L188-L266
+macro_rules! impl_Integer {
+    ($($max_len:expr => $t:ident),* as $conv_fn:ident) => {$(
+        impl Integer for $t {}
+
+        impl private::Sealed for $t {
+            type Buffer = [MaybeUninit<u8>; $max_len];
+
+            #[allow(unused_comparisons)]
+            #[inline]
+            #[cfg_attr(feature = "no-panic", no_panic)]
+            fn write(self, buf: &mut [MaybeUninit<u8>; $max_len]) -> &str {
+                let is_nonnegative = self >= 0;
+                let mut n = if is_nonnegative {
+                    self as $conv_fn
+                } else {
+                    // convert the negative num to positive by summing 1 to it's 2 complement
+                    (!(self as $conv_fn)).wrapping_add(1)
+                };
+                let mut curr = buf.len() as isize;
+                let buf_ptr = buf.as_mut_ptr() as *mut u8;
+                let lut_ptr = DEC_DIGITS_LUT.as_ptr();
+
+                unsafe {
+                    // need at least 16 bits for the 4-characters-at-a-time to work.
+                    if mem::size_of::<$t>() >= 2 {
+                        // eagerly decode 4 characters at a time
+                        while n >= 10000 {
+                            let rem = (n % 10000) as isize;
+                            n /= 10000;
+
+                            let d1 = (rem / 100) << 1;
+                            let d2 = (rem % 100) << 1;
+                            curr -= 4;
+                            ptr::copy_nonoverlapping(lut_ptr.offset(d1), buf_ptr.offset(curr), 2);
+                            ptr::copy_nonoverlapping(lut_ptr.offset(d2), buf_ptr.offset(curr + 2), 2);
+                        }
+                    }
+
+                    // if we reach here numbers are <= 9999, so at most 4 chars long
+                    let mut n = n as isize; // possibly reduce 64bit math
+
+                    // decode 2 more chars, if > 2 chars
+                    if n >= 100 {
+                        let d1 = (n % 100) << 1;
+                        n /= 100;
+                        curr -= 2;
+                        ptr::copy_nonoverlapping(lut_ptr.offset(d1), buf_ptr.offset(curr), 2);
+                    }
+
+                    // decode last 1 or 2 chars
+                    if n < 10 {
+                        curr -= 1;
+                        *buf_ptr.offset(curr) = (n as u8) + b'0';
+                    } else {
+                        let d1 = n << 1;
+                        curr -= 2;
+                        ptr::copy_nonoverlapping(lut_ptr.offset(d1), buf_ptr.offset(curr), 2);
+                    }
+
+                    if !is_nonnegative {
+                        curr -= 1;
+                        *buf_ptr.offset(curr) = b'-';
+                    }
+                }
+
+                let len = buf.len() - curr as usize;
+                let bytes = unsafe { slice::from_raw_parts(buf_ptr.offset(curr), len) };
+                unsafe { str::from_utf8_unchecked(bytes) }
+            }
+        }
+    )*};
+}
+
+const I8_MAX_LEN: usize = 4;
+const U8_MAX_LEN: usize = 3;
+const I16_MAX_LEN: usize = 6;
+const U16_MAX_LEN: usize = 5;
+const I32_MAX_LEN: usize = 11;
+const U32_MAX_LEN: usize = 10;
+const I64_MAX_LEN: usize = 20;
+const U64_MAX_LEN: usize = 20;
+
+impl_Integer!(
+    I8_MAX_LEN => i8,
+    U8_MAX_LEN => u8,
+    I16_MAX_LEN => i16,
+    U16_MAX_LEN => u16,
+    I32_MAX_LEN => i32,
+    U32_MAX_LEN => u32
+    as u32);
+
+impl_Integer!(I64_MAX_LEN => i64, U64_MAX_LEN => u64 as u64);
+
+#[cfg(target_pointer_width = "16")]
+impl_Integer!(I16_MAX_LEN => isize, U16_MAX_LEN => usize as u16);
+
+#[cfg(target_pointer_width = "32")]
+impl_Integer!(I32_MAX_LEN => isize, U32_MAX_LEN => usize as u32);
+
+#[cfg(target_pointer_width = "64")]
+impl_Integer!(I64_MAX_LEN => isize, U64_MAX_LEN => usize as u64);
+
+macro_rules! impl_Integer128 {
+    ($($max_len:expr => $t:ident),*) => {$(
+        impl Integer for $t {}
+
+        impl private::Sealed for $t {
+            type Buffer = [MaybeUninit<u8>; $max_len];
+
+            #[allow(unused_comparisons)]
+            #[inline]
+            #[cfg_attr(feature = "no-panic", no_panic)]
+            fn write(self, buf: &mut [MaybeUninit<u8>; $max_len]) -> &str {
+                let is_nonnegative = self >= 0;
+                let n = if is_nonnegative {
+                    self as u128
+                } else {
+                    // convert the negative num to positive by summing 1 to it's 2 complement
+                    (!(self as u128)).wrapping_add(1)
+                };
+                let mut curr = buf.len() as isize;
+                let buf_ptr = buf.as_mut_ptr() as *mut u8;
+
+                unsafe {
+                    // Divide by 10^19 which is the highest power less than 2^64.
+                    let (n, rem) = udiv128::udivmod_1e19(n);
+                    let buf1 = buf_ptr.offset(curr - U64_MAX_LEN as isize) as *mut [MaybeUninit<u8>; U64_MAX_LEN];
+                    curr -= rem.write(&mut *buf1).len() as isize;
+
+                    if n != 0 {
+                        // Memset the base10 leading zeros of rem.
+                        let target = buf.len() as isize - 19;
+                        ptr::write_bytes(buf_ptr.offset(target), b'0', (curr - target) as usize);
+                        curr = target;
+
+                        // Divide by 10^19 again.
+                        let (n, rem) = udiv128::udivmod_1e19(n);
+                        let buf2 = buf_ptr.offset(curr - U64_MAX_LEN as isize) as *mut [MaybeUninit<u8>; U64_MAX_LEN];
+                        curr -= rem.write(&mut *buf2).len() as isize;
+
+                        if n != 0 {
+                            // Memset the leading zeros.
+                            let target = buf.len() as isize - 38;
+                            ptr::write_bytes(buf_ptr.offset(target), b'0', (curr - target) as usize);
+                            curr = target;
+
+                            // There is at most one digit left
+                            // because u128::max / 10^19 / 10^19 is 3.
+                            curr -= 1;
+                            *buf_ptr.offset(curr) = (n as u8) + b'0';
+                        }
+                    }
+
+                    if !is_nonnegative {
+                        curr -= 1;
+                        *buf_ptr.offset(curr) = b'-';
+                    }
+
+                    let len = buf.len() - curr as usize;
+                    let bytes = slice::from_raw_parts(buf_ptr.offset(curr), len);
+                    str::from_utf8_unchecked(bytes)
+                }
+            }
+        }
+    )*};
+}
+
+const U128_MAX_LEN: usize = 39;
+const I128_MAX_LEN: usize = 40;
+
+impl_Integer128!(I128_MAX_LEN => i128, U128_MAX_LEN => u128);