1 files changed, 183 insertions, 0 deletions
diff --git a/third_party/rust/flate2/src/ffi/rust.rs b/third_party/rust/flate2/src/ffi/rust.rs
new file mode 100644
index 0000000000..eadd6ec187
--- /dev/null
+++ b/third_party/rust/flate2/src/ffi/rust.rs
@@ -0,0 +1,183 @@
+//! Implementation for miniz_oxide rust backend.
+
+use std::convert::TryInto;
+use std::fmt;
+
+use miniz_oxide::deflate::core::CompressorOxide;
+use miniz_oxide::inflate::stream::InflateState;
+pub use miniz_oxide::*;
+
+pub const MZ_NO_FLUSH: isize = MZFlush::None as isize;
+pub const MZ_PARTIAL_FLUSH: isize = MZFlush::Partial as isize;
+pub const MZ_SYNC_FLUSH: isize = MZFlush::Sync as isize;
+pub const MZ_FULL_FLUSH: isize = MZFlush::Full as isize;
+pub const MZ_FINISH: isize = MZFlush::Finish as isize;
+
+use super::*;
+use crate::mem;
+
+// miniz_oxide doesn't provide any error messages (yet?)
+#[derive(Default)]
+pub struct ErrorMessage;
+
+impl ErrorMessage {
+    pub fn get(&self) -> Option<&str> {
+        None
+    }
+}
+
+fn format_from_bool(zlib_header: bool) -> DataFormat {
+    if zlib_header {
+        DataFormat::Zlib
+    } else {
+        DataFormat::Raw
+    }
+}
+
+pub struct Inflate {
+    inner: Box<InflateState>,
+    total_in: u64,
+    total_out: u64,
+}
+
+impl fmt::Debug for Inflate {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        write!(
+            f,
+            "miniz_oxide inflate internal state. total_in: {}, total_out: {}",
+            self.total_in, self.total_out,
+        )
+    }
+}
+
+impl InflateBackend for Inflate {
+    fn make(zlib_header: bool, _window_bits: u8) -> Self {
+        let format = format_from_bool(zlib_header);
+
+        Inflate {
+            inner: InflateState::new_boxed(format),
+            total_in: 0,
+            total_out: 0,
+        }
+    }
+
+    fn decompress(
+        &mut self,
+        input: &[u8],
+        output: &mut [u8],
+        flush: FlushDecompress,
+    ) -> Result<Status, DecompressError> {
+        let flush = MZFlush::new(flush as i32).unwrap();
+
+        let res = inflate::stream::inflate(&mut self.inner, input, output, flush);
+        self.total_in += res.bytes_consumed as u64;
+        self.total_out += res.bytes_written as u64;
+
+        match res.status {
+            Ok(status) => match status {
+                MZStatus::Ok => Ok(Status::Ok),
+                MZStatus::StreamEnd => Ok(Status::StreamEnd),
+                MZStatus::NeedDict => {
+                    mem::decompress_need_dict(self.inner.decompressor().adler32().unwrap_or(0))
+                }
+            },
+            Err(status) => match status {
+                MZError::Buf => Ok(Status::BufError),
+                _ => mem::decompress_failed(ErrorMessage),
+            },
+        }
+    }
+
+    fn reset(&mut self, zlib_header: bool) {
+        self.inner.reset(format_from_bool(zlib_header));
+        self.total_in = 0;
+        self.total_out = 0;
+    }
+}
+
+impl Backend for Inflate {
+    #[inline]
+    fn total_in(&self) -> u64 {
+        self.total_in
+    }
+
+    #[inline]
+    fn total_out(&self) -> u64 {
+        self.total_out
+    }
+}
+
+pub struct Deflate {
+    inner: Box<CompressorOxide>,
+    total_in: u64,
+    total_out: u64,
+}
+
+impl fmt::Debug for Deflate {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        write!(
+            f,
+            "miniz_oxide deflate internal state. total_in: {}, total_out: {}",
+            self.total_in, self.total_out,
+        )
+    }
+}
+
+impl DeflateBackend for Deflate {
+    fn make(level: Compression, zlib_header: bool, _window_bits: u8) -> Self {
+        // Check in case the integer value changes at some point.
+        debug_assert!(level.level() <= 10);
+
+        let mut inner: Box<CompressorOxide> = Box::default();
+        let format = format_from_bool(zlib_header);
+        inner.set_format_and_level(format, level.level().try_into().unwrap_or(1));
+
+        Deflate {
+            inner,
+            total_in: 0,
+            total_out: 0,
+        }
+    }
+
+    fn compress(
+        &mut self,
+        input: &[u8],
+        output: &mut [u8],
+        flush: FlushCompress,
+    ) -> Result<Status, CompressError> {
+        let flush = MZFlush::new(flush as i32).unwrap();
+        let res = deflate::stream::deflate(&mut self.inner, input, output, flush);
+        self.total_in += res.bytes_consumed as u64;
+        self.total_out += res.bytes_written as u64;
+
+        match res.status {
+            Ok(status) => match status {
+                MZStatus::Ok => Ok(Status::Ok),
+                MZStatus::StreamEnd => Ok(Status::StreamEnd),
+                MZStatus::NeedDict => mem::compress_failed(ErrorMessage),
+            },
+            Err(status) => match status {
+                MZError::Buf => Ok(Status::BufError),
+                _ => mem::compress_failed(ErrorMessage),
+            },
+        }
+    }
+
+    fn reset(&mut self) {
+        self.total_in = 0;
+        self.total_out = 0;
+        self.inner.reset();
+    }
+}
+
+impl Backend for Deflate {
+    #[inline]
+    fn total_in(&self) -> u64 {
+        self.total_in
+    }
+
+    #[inline]
+    fn total_out(&self) -> u64 {
+        self.total_out
+    }
+}