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-rw-r--r--vendor/object-0.26.2/src/write/util.rs129
1 files changed, 129 insertions, 0 deletions
diff --git a/vendor/object-0.26.2/src/write/util.rs b/vendor/object-0.26.2/src/write/util.rs
new file mode 100644
index 000000000..bb6b8597b
--- /dev/null
+++ b/vendor/object-0.26.2/src/write/util.rs
@@ -0,0 +1,129 @@
+use std::vec::Vec;
+
+use crate::pod::{bytes_of, bytes_of_slice, Pod};
+
+/// Trait for writable buffer.
+#[allow(clippy::len_without_is_empty)]
+pub trait WritableBuffer {
+ /// Returns position/offset for data to be written at.
+ fn len(&self) -> usize;
+
+ /// Reserves specified number of bytes in the buffer.
+ fn reserve(&mut self, additional: usize) -> Result<(), ()>;
+
+ /// Writes the specified value at the end of the buffer
+ /// until the buffer has the specified length.
+ fn resize(&mut self, new_len: usize, value: u8);
+
+ /// Writes the specified slice of bytes at the end of the buffer.
+ fn write_bytes(&mut self, val: &[u8]);
+
+ /// Writes the specified `Pod` type at the end of the buffer.
+ fn write_pod<T: Pod>(&mut self, val: &T)
+ where
+ Self: Sized,
+ {
+ self.write_bytes(bytes_of(val))
+ }
+
+ /// Writes the specified `Pod` slice at the end of the buffer.
+ fn write_pod_slice<T: Pod>(&mut self, val: &[T])
+ where
+ Self: Sized,
+ {
+ self.write_bytes(bytes_of_slice(val))
+ }
+}
+
+impl<'a> dyn WritableBuffer + 'a {
+ /// Writes the specified `Pod` type at the end of the buffer.
+ pub fn write<T: Pod>(&mut self, val: &T) {
+ self.write_bytes(bytes_of(val))
+ }
+
+ /// Writes the specified `Pod` slice at the end of the buffer.
+ pub fn write_slice<T: Pod>(&mut self, val: &[T]) {
+ self.write_bytes(bytes_of_slice(val))
+ }
+}
+
+impl WritableBuffer for Vec<u8> {
+ #[inline]
+ fn len(&self) -> usize {
+ self.len()
+ }
+
+ #[inline]
+ fn reserve(&mut self, additional: usize) -> Result<(), ()> {
+ self.reserve(additional);
+ Ok(())
+ }
+
+ #[inline]
+ fn resize(&mut self, new_len: usize, value: u8) {
+ self.resize(new_len, value);
+ }
+
+ #[inline]
+ fn write_bytes(&mut self, val: &[u8]) {
+ self.extend_from_slice(val)
+ }
+}
+
+/// A trait for mutable byte slices.
+///
+/// It provides convenience methods for `Pod` types.
+pub(crate) trait BytesMut {
+ fn write_at<T: Pod>(self, offset: usize, val: &T) -> Result<(), ()>;
+}
+
+impl<'a> BytesMut for &'a mut [u8] {
+ #[inline]
+ fn write_at<T: Pod>(self, offset: usize, val: &T) -> Result<(), ()> {
+ let src = bytes_of(val);
+ let dest = self.get_mut(offset..).ok_or(())?;
+ let dest = dest.get_mut(..src.len()).ok_or(())?;
+ dest.copy_from_slice(src);
+ Ok(())
+ }
+}
+
+pub(crate) fn align(offset: usize, size: usize) -> usize {
+ (offset + (size - 1)) & !(size - 1)
+}
+
+#[allow(dead_code)]
+pub(crate) fn align_u64(offset: u64, size: u64) -> u64 {
+ (offset + (size - 1)) & !(size - 1)
+}
+
+pub(crate) fn write_align(buffer: &mut dyn WritableBuffer, size: usize) {
+ let new_len = align(buffer.len(), size);
+ buffer.resize(new_len, 0);
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+
+ #[test]
+ fn bytes_mut() {
+ let data = vec![0x01, 0x23, 0x45, 0x67];
+
+ let mut bytes = data.clone();
+ bytes.extend_from_slice(bytes_of(&u16::to_be(0x89ab)));
+ assert_eq!(bytes, [0x01, 0x23, 0x45, 0x67, 0x89, 0xab]);
+
+ let mut bytes = data.clone();
+ assert_eq!(bytes.write_at(0, &u16::to_be(0x89ab)), Ok(()));
+ assert_eq!(bytes, [0x89, 0xab, 0x45, 0x67]);
+
+ let mut bytes = data.clone();
+ assert_eq!(bytes.write_at(2, &u16::to_be(0x89ab)), Ok(()));
+ assert_eq!(bytes, [0x01, 0x23, 0x89, 0xab]);
+
+ assert_eq!(bytes.write_at(3, &u16::to_be(0x89ab)), Err(()));
+ assert_eq!(bytes.write_at(4, &u16::to_be(0x89ab)), Err(()));
+ assert_eq!(vec![].write_at(0, &u32::to_be(0x89ab)), Err(()));
+ }
+}