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-rw-r--r--vendor/tinystr/src/helpers.rs32
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))
+}