Add `libqoi` helper crate that wraps qoi.h

This commit is contained in:
Ivan Smirnov 2022-01-05 17:07:30 +03:00
parent 50d268cd14
commit 81bd8abdbe
6 changed files with 95 additions and 1 deletions

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@ -26,7 +26,7 @@ reference = [] # follows reference encoder implementation precisely, but may be
bytemuck = "1.7"
[workspace]
members = ["bench"]
members = ["libqoi", "bench"]
[dev-dependencies]
anyhow = "1.0"

16
libqoi/Cargo.toml Normal file
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@ -0,0 +1,16 @@
[package]
name = "libqoi"
version = "0.1.0"
edition = "2018"
license = "MIT/Apache-2.0"
authors = ["Ivan Smirnov <rust@ivan.smirnov.ie>"]
description = "Bindings to the original qoi.h (for test purposes only)"
publish = false
[dependencies]
anyhow = "1.0"
c_vec = "2.0"
libc = "0.2"
[build-dependencies]
cc = "1.0"

2
libqoi/README.md Normal file
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@ -0,0 +1,2 @@
This crate provides direct bindings around the original `qoi.h`,
and is only used for testing and benchmarking purposes.

18
libqoi/build.rs Normal file
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@ -0,0 +1,18 @@
use std::env;
use std::fs;
use std::path::PathBuf;
fn main() {
let out_dir = PathBuf::from(env::var("OUT_DIR").unwrap());
let out_src = out_dir.join("qoi.c");
fs::write(&out_src, "#include \"qoi.h\"\n").unwrap();
cc::Build::new()
.file(&out_src)
.include("../ext/qoi")
.define("QOI_NO_STDIO", None)
.define("QOI_IMPLEMENTATION", None)
.flag("-Wno-unsequenced")
.opt_level(3)
.compile("qoi");
}

57
libqoi/src/lib.rs Normal file
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@ -0,0 +1,57 @@
use anyhow::{ensure, Result};
use c_vec::CVec;
use libc::{c_int, c_void};
mod ffi {
use libc::{c_int, c_uchar, c_uint, c_void};
#[derive(Debug, Copy, Clone, Default)]
#[repr(C)]
#[allow(non_camel_case_types)]
pub struct qoi_desc {
pub width: c_uint,
pub height: c_uint,
pub channels: c_uchar,
pub colorspace: c_uchar,
}
extern "C" {
pub fn qoi_encode(
data: *const c_void, desc: *const qoi_desc, out_len: *mut c_int,
) -> *mut c_void;
pub fn qoi_decode(
data: *const c_void, size: c_int, desc: *mut qoi_desc, channels: c_int,
) -> *mut c_void;
}
}
pub use ffi::qoi_desc;
pub fn qoi_encode(data: &[u8], width: u32, height: u32, channels: u8) -> Result<CVec<u8>> {
let desc =
qoi_desc { width: width as _, height: height as _, channels: channels as _, colorspace: 0 };
let mut out_len: c_int = 0;
let out_ptr =
unsafe { ffi::qoi_encode(data.as_ptr().cast(), &desc as *const _, &mut out_len as *mut _) };
ensure!(!out_ptr.is_null(), "qoi.h: qoi_encode() returned null pointer");
ensure!(out_len > 0, "qoi.h: qoi_encode() returned non-positive out_len");
let vec = unsafe {
CVec::new_with_dtor(out_ptr.cast::<u8>(), out_len as _, |p| libc::free(p.cast::<c_void>()))
};
Ok(vec)
}
pub fn qoi_decode(data: &[u8], channels: u8) -> Result<(qoi_desc, CVec<u8>)> {
let mut desc = qoi_desc::default();
let out_ptr = unsafe {
ffi::qoi_decode(data.as_ptr() as _, data.len() as _, &mut desc as *mut _, channels as _)
};
ensure!(!out_ptr.is_null(), "qoi.h: qoi_decode() returned null pointer");
let out_len = (desc.width as usize)
.saturating_mul(desc.height as usize)
.saturating_mul(channels as usize);
let vec = unsafe {
CVec::new_with_dtor(out_ptr.cast::<u8>(), out_len, |p| libc::free(p.cast::<c_void>()))
};
Ok((desc, vec))
}

1
libqoi/src/qoi.c Normal file
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@ -0,0 +1 @@
#include "qoi.h"