1 files changed, 421 insertions, 0 deletions
diff --git a/third_party/rust/flate2/src/ffi/c.rs b/third_party/rust/flate2/src/ffi/c.rs
new file mode 100644
index 0000000000..59e20118fb
--- /dev/null
+++ b/third_party/rust/flate2/src/ffi/c.rs
@@ -0,0 +1,421 @@
+//! Implementation for C backends.
+use std::alloc::{self, Layout};
+use std::cmp;
+use std::convert::TryFrom;
+use std::fmt;
+use std::marker;
+use std::ops::{Deref, DerefMut};
+use std::os::raw::{c_int, c_uint, c_void};
+use std::ptr;
+
+use super::*;
+use crate::mem::{self, FlushDecompress, Status};
+
+#[derive(Default)]
+pub struct ErrorMessage(Option<&'static str>);
+
+impl ErrorMessage {
+    pub fn get(&self) -> Option<&str> {
+        self.0
+    }
+}
+
+pub struct StreamWrapper {
+    pub inner: Box<mz_stream>,
+}
+
+impl fmt::Debug for StreamWrapper {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        write!(f, "StreamWrapper")
+    }
+}
+
+impl Default for StreamWrapper {
+    fn default() -> StreamWrapper {
+        StreamWrapper {
+            inner: Box::new(mz_stream {
+                next_in: ptr::null_mut(),
+                avail_in: 0,
+                total_in: 0,
+                next_out: ptr::null_mut(),
+                avail_out: 0,
+                total_out: 0,
+                msg: ptr::null_mut(),
+                adler: 0,
+                data_type: 0,
+                reserved: 0,
+                opaque: ptr::null_mut(),
+                state: ptr::null_mut(),
+                #[cfg(all(feature = "any_zlib", not(feature = "cloudflare-zlib-sys")))]
+                zalloc,
+                #[cfg(all(feature = "any_zlib", not(feature = "cloudflare-zlib-sys")))]
+                zfree,
+                #[cfg(not(all(feature = "any_zlib", not(feature = "cloudflare-zlib-sys"))))]
+                zalloc: Some(zalloc),
+                #[cfg(not(all(feature = "any_zlib", not(feature = "cloudflare-zlib-sys"))))]
+                zfree: Some(zfree),
+            }),
+        }
+    }
+}
+
+const ALIGN: usize = std::mem::align_of::<usize>();
+
+fn align_up(size: usize, align: usize) -> usize {
+    (size + align - 1) & !(align - 1)
+}
+
+extern "C" fn zalloc(_ptr: *mut c_void, items: AllocSize, item_size: AllocSize) -> *mut c_void {
+    // We need to multiply `items` and `item_size` to get the actual desired
+    // allocation size. Since `zfree` doesn't receive a size argument we
+    // also need to allocate space for a `usize` as a header so we can store
+    // how large the allocation is to deallocate later.
+    let size = match items
+        .checked_mul(item_size)
+        .and_then(|i| usize::try_from(i).ok())
+        .map(|size| align_up(size, ALIGN))
+        .and_then(|i| i.checked_add(std::mem::size_of::<usize>()))
+    {
+        Some(i) => i,
+        None => return ptr::null_mut(),
+    };
+
+    // Make sure the `size` isn't too big to fail `Layout`'s restrictions
+    let layout = match Layout::from_size_align(size, ALIGN) {
+        Ok(layout) => layout,
+        Err(_) => return ptr::null_mut(),
+    };
+
+    unsafe {
+        // Allocate the data, and if successful store the size we allocated
+        // at the beginning and then return an offset pointer.
+        let ptr = alloc::alloc(layout) as *mut usize;
+        if ptr.is_null() {
+            return ptr as *mut c_void;
+        }
+        *ptr = size;
+        ptr.add(1) as *mut c_void
+    }
+}
+
+extern "C" fn zfree(_ptr: *mut c_void, address: *mut c_void) {
+    unsafe {
+        // Move our address being freed back one pointer, read the size we
+        // stored in `zalloc`, and then free it using the standard Rust
+        // allocator.
+        let ptr = (address as *mut usize).offset(-1);
+        let size = *ptr;
+        let layout = Layout::from_size_align_unchecked(size, ALIGN);
+        alloc::dealloc(ptr as *mut u8, layout)
+    }
+}
+
+impl Deref for StreamWrapper {
+    type Target = mz_stream;
+
+    fn deref(&self) -> &Self::Target {
+        &*self.inner
+    }
+}
+
+impl DerefMut for StreamWrapper {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut *self.inner
+    }
+}
+
+unsafe impl<D: Direction> Send for Stream<D> {}
+unsafe impl<D: Direction> Sync for Stream<D> {}
+
+/// Trait used to call the right destroy/end function on the inner
+/// stream object on drop.
+pub trait Direction {
+    unsafe fn destroy(stream: *mut mz_stream) -> c_int;
+}
+
+#[derive(Debug)]
+pub enum DirCompress {}
+#[derive(Debug)]
+pub enum DirDecompress {}
+
+#[derive(Debug)]
+pub struct Stream<D: Direction> {
+    pub stream_wrapper: StreamWrapper,
+    pub total_in: u64,
+    pub total_out: u64,
+    pub _marker: marker::PhantomData<D>,
+}
+
+impl<D: Direction> Stream<D> {
+    pub fn msg(&self) -> ErrorMessage {
+        let msg = self.stream_wrapper.msg;
+        ErrorMessage(if msg.is_null() {
+            None
+        } else {
+            let s = unsafe { std::ffi::CStr::from_ptr(msg) };
+            std::str::from_utf8(s.to_bytes()).ok()
+        })
+    }
+}
+
+impl<D: Direction> Drop for Stream<D> {
+    fn drop(&mut self) {
+        unsafe {
+            let _ = D::destroy(&mut *self.stream_wrapper);
+        }
+    }
+}
+
+impl Direction for DirCompress {
+    unsafe fn destroy(stream: *mut mz_stream) -> c_int {
+        mz_deflateEnd(stream)
+    }
+}
+impl Direction for DirDecompress {
+    unsafe fn destroy(stream: *mut mz_stream) -> c_int {
+        mz_inflateEnd(stream)
+    }
+}
+
+#[derive(Debug)]
+pub struct Inflate {
+    pub inner: Stream<DirDecompress>,
+}
+
+impl InflateBackend for Inflate {
+    fn make(zlib_header: bool, window_bits: u8) -> Self {
+        unsafe {
+            let mut state = StreamWrapper::default();
+            let ret = mz_inflateInit2(
+                &mut *state,
+                if zlib_header {
+                    window_bits as c_int
+                } else {
+                    -(window_bits as c_int)
+                },
+            );
+            assert_eq!(ret, 0);
+            Inflate {
+                inner: Stream {
+                    stream_wrapper: state,
+                    total_in: 0,
+                    total_out: 0,
+                    _marker: marker::PhantomData,
+                },
+            }
+        }
+    }
+
+    fn decompress(
+        &mut self,
+        input: &[u8],
+        output: &mut [u8],
+        flush: FlushDecompress,
+    ) -> Result<Status, DecompressError> {
+        let raw = &mut *self.inner.stream_wrapper;
+        raw.msg = ptr::null_mut();
+        raw.next_in = input.as_ptr() as *mut u8;
+        raw.avail_in = cmp::min(input.len(), c_uint::max_value() as usize) as c_uint;
+        raw.next_out = output.as_mut_ptr();
+        raw.avail_out = cmp::min(output.len(), c_uint::max_value() as usize) as c_uint;
+
+        let rc = unsafe { mz_inflate(raw, flush as c_int) };
+
+        // Unfortunately the total counters provided by zlib might be only
+        // 32 bits wide and overflow while processing large amounts of data.
+        self.inner.total_in += (raw.next_in as usize - input.as_ptr() as usize) as u64;
+        self.inner.total_out += (raw.next_out as usize - output.as_ptr() as usize) as u64;
+
+        match rc {
+            MZ_DATA_ERROR | MZ_STREAM_ERROR => mem::decompress_failed(self.inner.msg()),
+            MZ_OK => Ok(Status::Ok),
+            MZ_BUF_ERROR => Ok(Status::BufError),
+            MZ_STREAM_END => Ok(Status::StreamEnd),
+            MZ_NEED_DICT => mem::decompress_need_dict(raw.adler as u32),
+            c => panic!("unknown return code: {}", c),
+        }
+    }
+
+    fn reset(&mut self, zlib_header: bool) {
+        let bits = if zlib_header {
+            MZ_DEFAULT_WINDOW_BITS
+        } else {
+            -MZ_DEFAULT_WINDOW_BITS
+        };
+        unsafe {
+            inflateReset2(&mut *self.inner.stream_wrapper, bits);
+        }
+        self.inner.total_out = 0;
+        self.inner.total_in = 0;
+    }
+}
+
+impl Backend for Inflate {
+    #[inline]
+    fn total_in(&self) -> u64 {
+        self.inner.total_in
+    }
+
+    #[inline]
+    fn total_out(&self) -> u64 {
+        self.inner.total_out
+    }
+}
+
+#[derive(Debug)]
+pub struct Deflate {
+    pub inner: Stream<DirCompress>,
+}
+
+impl DeflateBackend for Deflate {
+    fn make(level: Compression, zlib_header: bool, window_bits: u8) -> Self {
+        unsafe {
+            let mut state = StreamWrapper::default();
+            let ret = mz_deflateInit2(
+                &mut *state,
+                level.0 as c_int,
+                MZ_DEFLATED,
+                if zlib_header {
+                    window_bits as c_int
+                } else {
+                    -(window_bits as c_int)
+                },
+                8,
+                MZ_DEFAULT_STRATEGY,
+            );
+            assert_eq!(ret, 0);
+            Deflate {
+                inner: Stream {
+                    stream_wrapper: state,
+                    total_in: 0,
+                    total_out: 0,
+                    _marker: marker::PhantomData,
+                },
+            }
+        }
+    }
+    fn compress(
+        &mut self,
+        input: &[u8],
+        output: &mut [u8],
+        flush: FlushCompress,
+    ) -> Result<Status, CompressError> {
+        let raw = &mut *self.inner.stream_wrapper;
+        raw.msg = ptr::null_mut();
+        raw.next_in = input.as_ptr() as *mut _;
+        raw.avail_in = cmp::min(input.len(), c_uint::max_value() as usize) as c_uint;
+        raw.next_out = output.as_mut_ptr();
+        raw.avail_out = cmp::min(output.len(), c_uint::max_value() as usize) as c_uint;
+
+        let rc = unsafe { mz_deflate(raw, flush as c_int) };
+
+        // Unfortunately the total counters provided by zlib might be only
+        // 32 bits wide and overflow while processing large amounts of data.
+        self.inner.total_in += (raw.next_in as usize - input.as_ptr() as usize) as u64;
+        self.inner.total_out += (raw.next_out as usize - output.as_ptr() as usize) as u64;
+
+        match rc {
+            MZ_OK => Ok(Status::Ok),
+            MZ_BUF_ERROR => Ok(Status::BufError),
+            MZ_STREAM_END => Ok(Status::StreamEnd),
+            MZ_STREAM_ERROR => mem::compress_failed(self.inner.msg()),
+            c => panic!("unknown return code: {}", c),
+        }
+    }
+
+    fn reset(&mut self) {
+        self.inner.total_in = 0;
+        self.inner.total_out = 0;
+        let rc = unsafe { mz_deflateReset(&mut *self.inner.stream_wrapper) };
+        assert_eq!(rc, MZ_OK);
+    }
+}
+
+impl Backend for Deflate {
+    #[inline]
+    fn total_in(&self) -> u64 {
+        self.inner.total_in
+    }
+
+    #[inline]
+    fn total_out(&self) -> u64 {
+        self.inner.total_out
+    }
+}
+
+pub use self::c_backend::*;
+
+/// For backwards compatibility, we provide symbols as `mz_` to mimic the miniz API
+#[allow(bad_style)]
+mod c_backend {
+    use std::mem;
+    use std::os::raw::{c_char, c_int};
+
+    #[cfg(feature = "zlib-ng")]
+    use libz_ng_sys as libz;
+
+    #[cfg(all(not(feature = "zlib-ng"), feature = "cloudflare_zlib"))]
+    use cloudflare_zlib_sys as libz;
+
+    #[cfg(all(not(feature = "cloudflare_zlib"), not(feature = "zlib-ng")))]
+    use libz_sys as libz;
+
+    pub use libz::deflate as mz_deflate;
+    pub use libz::deflateEnd as mz_deflateEnd;
+    pub use libz::deflateReset as mz_deflateReset;
+    pub use libz::inflate as mz_inflate;
+    pub use libz::inflateEnd as mz_inflateEnd;
+    pub use libz::z_stream as mz_stream;
+    pub use libz::*;
+
+    pub use libz::Z_BLOCK as MZ_BLOCK;
+    pub use libz::Z_BUF_ERROR as MZ_BUF_ERROR;
+    pub use libz::Z_DATA_ERROR as MZ_DATA_ERROR;
+    pub use libz::Z_DEFAULT_STRATEGY as MZ_DEFAULT_STRATEGY;
+    pub use libz::Z_DEFLATED as MZ_DEFLATED;
+    pub use libz::Z_FINISH as MZ_FINISH;
+    pub use libz::Z_FULL_FLUSH as MZ_FULL_FLUSH;
+    pub use libz::Z_NEED_DICT as MZ_NEED_DICT;
+    pub use libz::Z_NO_FLUSH as MZ_NO_FLUSH;
+    pub use libz::Z_OK as MZ_OK;
+    pub use libz::Z_PARTIAL_FLUSH as MZ_PARTIAL_FLUSH;
+    pub use libz::Z_STREAM_END as MZ_STREAM_END;
+    pub use libz::Z_STREAM_ERROR as MZ_STREAM_ERROR;
+    pub use libz::Z_SYNC_FLUSH as MZ_SYNC_FLUSH;
+    pub type AllocSize = libz::uInt;
+
+    pub const MZ_DEFAULT_WINDOW_BITS: c_int = 15;
+
+    #[cfg(feature = "zlib-ng")]
+    const ZLIB_VERSION: &'static str = "2.1.0.devel\0";
+    #[cfg(not(feature = "zlib-ng"))]
+    const ZLIB_VERSION: &'static str = "1.2.8\0";
+
+    pub unsafe extern "C" fn mz_deflateInit2(
+        stream: *mut mz_stream,
+        level: c_int,
+        method: c_int,
+        window_bits: c_int,
+        mem_level: c_int,
+        strategy: c_int,
+    ) -> c_int {
+        libz::deflateInit2_(
+            stream,
+            level,
+            method,
+            window_bits,
+            mem_level,
+            strategy,
+            ZLIB_VERSION.as_ptr() as *const c_char,
+            mem::size_of::<mz_stream>() as c_int,
+        )
+    }
+    pub unsafe extern "C" fn mz_inflateInit2(stream: *mut mz_stream, window_bits: c_int) -> c_int {
+        libz::inflateInit2_(
+            stream,
+            window_bits,
+            ZLIB_VERSION.as_ptr() as *const c_char,
+            mem::size_of::<mz_stream>() as c_int,
+        )
+    }
+}