diff options
Diffstat (limited to 'vendor/tinystr/src/helpers.rs')
-rw-r--r-- | vendor/tinystr/src/helpers.rs | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/vendor/tinystr/src/helpers.rs b/vendor/tinystr/src/helpers.rs new file mode 100644 index 000000000..c3d17d028 --- /dev/null +++ b/vendor/tinystr/src/helpers.rs @@ -0,0 +1,32 @@ +use std::num::NonZeroU32; +use std::ptr::copy_nonoverlapping; + +use super::Error; + +#[cfg(any(feature = "std", test))] +pub use std::string::String; + +#[cfg(all(not(feature = "std"), not(test)))] +extern crate alloc; + +#[cfg(all(not(feature = "std"), not(test)))] +pub use alloc::string::String; + +#[inline(always)] +pub(crate) unsafe fn make_4byte_bytes( + bytes: &[u8], + len: usize, + mask: u32, +) -> Result<NonZeroU32, Error> { + // Mask is always supplied as little-endian. + let mask = u32::from_le(mask); + let mut word: u32 = 0; + copy_nonoverlapping(bytes.as_ptr(), &mut word as *mut u32 as *mut u8, len); + if (word & mask) != 0 { + return Err(Error::NonAscii); + } + if ((mask - word) & mask) != 0 { + return Err(Error::InvalidNull); + } + Ok(NonZeroU32::new_unchecked(word)) +} |