Skip to content

Commit

Permalink
add zlib-rs support via the libz-rs-sys C api for zlib-rs
Browse files Browse the repository at this point in the history
  • Loading branch information
@folkertdev
folkertdev committed Apr 16, 2024
1 parent ae78497 commit e9232c7
Show file tree
Hide file tree
Showing 3 changed files with 90 additions and 57 deletions.
2 changes: 2 additions & 0 deletions .github/workflows/main.yml
View file
Original file line number Diff line number Diff line change
Expand Up @@ -43,6 +43,8 @@ jobs:
if: matrix.build != 'mingw'
- run: cargo test --features zlib-ng --no-default-features
if: matrix.build != 'mingw'
- run: cargo test --features zlib-rs --no-default-features
if: matrix.build != 'mingw'
- run: cargo test --features cloudflare_zlib --no-default-features
if: matrix.build != 'mingw'
- run: |
Expand Down
2 changes: 2 additions & 0 deletions Cargo.toml
View file
Original file line number Diff line number Diff line change
Expand Up @@ -19,6 +19,7 @@ and raw deflate streams.
[dependencies]
libz-sys = { version = "1.1.8", optional = true, default-features = false }
libz-ng-sys = { version = "1.1.8", optional = true }
libz-rs-sys = { version = "0.1.0", optional = true, default-features = false, features = ["std", "rust-allocator"] }
cloudflare-zlib-sys = { version = "0.3.0", optional = true }
miniz_oxide = { version = "0.7.1", optional = true, default-features = false, features = ["with-alloc"] }
crc32fast = "1.2.0"
Expand All @@ -38,6 +39,7 @@ zlib = ["any_zlib", "libz-sys"]
zlib-default = ["any_zlib", "libz-sys/default"]
zlib-ng-compat = ["zlib", "libz-sys/zlib-ng"]
zlib-ng = ["any_zlib", "libz-ng-sys"]
zlib-rs = ["any_zlib", "libz-rs-sys"]
cloudflare_zlib = ["any_zlib", "cloudflare-zlib-sys"]
rust_backend = ["miniz_oxide", "any_impl"]
miniz-sys = ["rust_backend"] # For backwards compatibility
Expand Down
143 changes: 86 additions & 57 deletions src/ffi/c.rs
View file
Original file line number Diff line number Diff line change
@@ -1,10 +1,8 @@
//! Implementation for C backends.
use std::alloc::{self, Layout};
use std::cmp;
use std::convert::TryFrom;
use std::fmt;
use std::marker;
use std::os::raw::{c_int, c_uint, c_void};
use std::os::raw::{c_int, c_uint};
use std::ptr;

use super::*;
Expand Down Expand Up @@ -52,14 +50,28 @@ impl Default for StreamWrapper {
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),
#[cfg(all(
feature = "any_zlib",
not(any(feature = "cloudflare-zlib-sys", feature = "libz-rs-sys"))
))]
zalloc: allocator::zalloc,
#[cfg(all(
feature = "any_zlib",
not(any(feature = "cloudflare-zlib-sys", feature = "libz-rs-sys"))
))]
zfree: allocator::zfree,

#[cfg(all(feature = "any_zlib", feature = "cloudflare-zlib-sys"))]
zalloc: Some(allocator::zalloc),
#[cfg(all(feature = "any_zlib", feature = "cloudflare-zlib-sys"))]
zfree: Some(allocator::zfree),

// for zlib-rs, it is most efficient to have it provide the allocator.
// The libz-rs-sys dependency is configured to use the rust system allocator
#[cfg(all(feature = "any_zlib", feature = "libz-rs-sys"))]
zalloc: None,
#[cfg(all(feature = "any_zlib", feature = "libz-rs-sys"))]
zfree: None,
})),
}
}
Expand All @@ -75,54 +87,63 @@ impl Drop for StreamWrapper {
}
}

const ALIGN: usize = std::mem::align_of::<usize>();
#[cfg(all(feature = "any_zlib", not(feature = "libz-rs-sys")))]
mod allocator {
use super::*;

fn align_up(size: usize, align: usize) -> usize {
(size + align - 1) & !(align - 1)
}
use std::alloc::{self, Layout};
use std::convert::TryFrom;
use std::os::raw::c_void;

const ALIGN: usize = std::mem::align_of::<usize>();

fn align_up(size: usize, align: usize) -> usize {
(size + align - 1) & !(align - 1)
}

pub extern "C" fn zalloc(_ptr: *mut c_void, items: uInt, item_size: uInt) -> *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(),
};

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;
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
}
*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)
pub 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)
}
}
}

Expand Down Expand Up @@ -382,10 +403,17 @@ mod c_backend {
#[cfg(feature = "zlib-ng")]
use libz_ng_sys as libz;

#[cfg(feature = "zlib-rs")]
use libz_rs_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")))]
#[cfg(all(
not(feature = "cloudflare_zlib"),
not(feature = "zlib-ng"),
not(feature = "zlib-rs")
))]
use libz_sys as libz;

pub use libz::deflate as mz_deflate;
Expand All @@ -410,13 +438,14 @@ mod c_backend {
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"))]
#[cfg(feature = "zlib-rs")]
const ZLIB_VERSION: &'static str = "0.1.0\0";
#[cfg(not(any(feature = "zlib-ng", feature = "zlib-rs")))]
const ZLIB_VERSION: &'static str = "1.2.8\0";

pub unsafe extern "C" fn mz_deflateInit2(
Expand Down

0 comments on commit e9232c7

Please sign in to comment.