A common library for linking libz to Rust programs (also known as zlib).
This also serves as the source for the libz-ng-sys crate, which builds
zlib-ng natively (not in zlib-compat mode). See
README-zng.md for details.
This crate provides bindings to the raw low-level C API. For a higher-level
safe API to work with DEFLATE, zlib, or gzip streams, see
flate2. flate2 also supports alternative
implementations, including slower but pure Rust implementations.
This crate supports building either the high-performance zlib-ng (in zlib-compat mode), or the widely available stock zlib.
By default, libz-sys uses stock zlib, primarily because doing so allows the
use of a shared system zlib library if available.
Any application or library designed for zlib should work with zlib-ng in
zlib-compat mode, as long as it doesn't make assumptions about the exact size
or output of the deflated data (e.g. "compressing this data produces exactly
this many bytes"), and as long as you don't also dynamically pull in a copy of
stock zlib (which will produce conflicting symbols). Nonetheless, for maximum
compatibility, every library crate in a build must opt into allowing zlib-ng;
if any library crate in your dependency graph wants stock zlib, libz-sys will
use stock zlib.
Library crates depending on libz-sys should use:
libz-sys = { version = "1.1", default-features = false, features = ["libc"] }(Omit the libc feature if you don't require the corresponding functions.)
This allows higher-level crates depending on your library to opt into zlib-ng if desired.
Building zlib-ng requires cmake unless the
zlib-ng-no-cmake-experimental-community-maintained feature is enabled,
in which case cc is used instead. Note that this option enables all compiler
features that are supported for the given target, which may not compile on older
compilers or targets without certain headers.
Crates that don't require compatibility with the zlib C API, and use zlib
exclusively from Rust or support the zlib-ng native C API (prefixed with
zng_) can use libz-ng-sys instead,
which allows zlib and zlib-ng to coexist in the same program. See
README-zng.md for details.
This crate uses the same MSRV policy as the
flate2 crate: This crate supports the
current and previous stable versions of Rust. Older versions of Rust may work,
but we don't guarantee these will continue to work.
This project is licensed under either of
- Apache License, Version 2.0, (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or https://opensource.org/license/mit/)
at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in libz-sys by you, as defined in the Apache-2.0 license, shall
be dual licensed as above, without any additional terms or conditions.