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-rw-r--r--vendor/flate2/src/ffi/c.rs433
1 files changed, 433 insertions, 0 deletions
diff --git a/vendor/flate2/src/ffi/c.rs b/vendor/flate2/src/ffi/c.rs
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--- /dev/null
+++ b/vendor/flate2/src/ffi/c.rs
@@ -0,0 +1,433 @@
+//! 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 as usize) as c_uint;
+ raw.next_out = output.as_mut_ptr();
+ raw.avail_out = cmp::min(output.len(), c_uint::MAX 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;
+
+ // reset these pointers so we don't accidentally read them later
+ raw.next_in = ptr::null_mut();
+ raw.avail_in = 0;
+ raw.next_out = ptr::null_mut();
+ raw.avail_out = 0;
+
+ 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 as usize) as c_uint;
+ raw.next_out = output.as_mut_ptr();
+ raw.avail_out = cmp::min(output.len(), c_uint::MAX 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;
+
+ // reset these pointers so we don't accidentally read them later
+ raw.next_in = ptr::null_mut();
+ raw.avail_in = 0;
+ raw.next_out = ptr::null_mut();
+ raw.avail_out = 0;
+
+ 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,
+ )
+ }
+}