refactor: init

senbei-crypto/src/lib.rs

@@ -0,0 +1,77 @@
+//! Cryptographic, checksum, compression, and bytecode primitives.
+
+pub mod bytecode;
+pub mod crc32;
+pub mod primitives;
+mod tables;
+
+/// Maximum buffer size accepted by allocation-sensitive transforms.
+pub const MAX_IMAGE_SIZE: u64 = 1 << 30;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum BufferOperation {
+    Read,
+    CopySource,
+    CopyDestination,
+    ZeroFill,
+}
+
+impl std::fmt::Display for BufferOperation {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.write_str(match self {
+            Self::Read => "read",
+            Self::CopySource => "copy source",
+            Self::CopyDestination => "copy destination",
+            Self::ZeroFill => "zero-fill",
+        })
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, thiserror::Error)]
+pub enum Error {
+    #[error(
+        "{operation} range out of bounds (offset {offset}, size {size}, buffer length {buffer_len})"
+    )]
+    BufferRangeOutOfBounds {
+        operation: BufferOperation,
+        offset: usize,
+        size: usize,
+        buffer_len: usize,
+    },
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, thiserror::Error)]
+#[non_exhaustive]
+pub enum DecompressionFailure {
+    #[error("compressed source size {size} exceeds limit {max}")]
+    SourceTooLarge { size: u32, max: u64 },
+    #[error("Huffman code length {bits} is invalid")]
+    InvalidCodeLength { bits: u8 },
+    #[error("Huffman tree traversal exceeded 64 levels")]
+    HuffmanTraversalLimit,
+    #[error("pending length accumulator overflowed at {pending}")]
+    PendingLengthOverflow { pending: u32 },
+    #[error("output step {step} at byte {written} exceeds expected size {expected}")]
+    OutputOverflow {
+        written: u32,
+        step: u32,
+        expected: u32,
+    },
+    #[error("run-fill width {width} reads before output offset 0x{destination:08X}")]
+    RunFillBeforeOutput { width: u32, destination: u32 },
+    #[error("run-fill width {width} is unsupported")]
+    InvalidRunFillWidth { width: u32 },
+    #[error("back-reference distance {distance} exceeds {written} written bytes")]
+    InvalidBackReference { distance: u32, written: u32 },
+    #[error("Huffman symbol consumed no input and produced no output")]
+    NoProgress,
+    #[error(
+        "output size mismatch (wrote {written}/{expected} bytes after consuming {consumed}/{source_size})"
+    )]
+    OutputSizeMismatch {
+        written: u32,
+        expected: u32,
+        consumed: u32,
+        source_size: u32,
+    },
+}