Vendor dependencies for 0.3.0 release

vendor/ruzstd/src/common/mod.rs

@@ -0,0 +1,21 @@
+//! Values and interfaces shared between the encoding side
+//! and the decoding side.
+
+// --- FRAMES ---
+/// This magic number is included at the start of a single Zstandard frame
+pub const MAGIC_NUM: u32 = 0xFD2F_B528;
+/// Window size refers to the minimum amount of memory needed to decode any given frame.
+///
+/// The minimum window size is defined as 1 KB
+pub const MIN_WINDOW_SIZE: u64 = 1024;
+/// Window size refers to the minimum amount of memory needed to decode any given frame.
+///
+/// The maximum window size allowed by the spec is 3.75TB
+pub const MAX_WINDOW_SIZE: u64 = (1 << 41) + 7 * (1 << 38);
+
+// --- BLOCKS ---
+/// While the spec limits block size to 128KB, the implementation uses
+/// 128kibibytes
+///
+/// <https://github.com/facebook/zstd/blob/eca205fc7849a61ab287492931a04960ac58e031/doc/educational_decoder/zstd_decompress.c#L28-L29>
+pub const MAX_BLOCK_SIZE: u32 = 128 * 1024;