use std::env;
use std::process;
use std::path::PathBuf;
use std::fs;
fn main() {
let build = cfg!(feature = "build");
let std_zlib = cfg!(feature = "zlib-sys");
let wants_static = build || cfg!(feature = "static") || env::var("PNG_STATIC").is_ok();
if build || wants_static {
build_static(std_zlib);
return;
}
if !try_libpng_config(wants_static, std_zlib) && !try_pkgconfig(wants_static) {
build_static(std_zlib);
}
}
fn try_libpng_config(wants_static: bool, std_zlib: bool) -> bool {
let cross_compile = env::var("TARGET") != env::var("HOST");
if cross_compile {
return false; }
if let Some(ver) = libpng_config(wants_static, "--version") {
let mut ver = ver.split('.');
let major = ver.next().and_then(|n| n.parse().ok()).unwrap_or(0);
let minor = ver.next().and_then(|n| n.parse().ok()).unwrap_or(0);
if major == 1 && minor < 6 {
return false;
}
} else {
return false;
}
if let Some(libdir) = libpng_config(wants_static, "--libdir") {
if let Some(args) = libpng_config(wants_static, "--libs") {
let libdir = libdir.trim_end();
println!("cargo:rustc-link-search=native={}", libdir);
println!("cargo:root={}", libdir);
libs_from_args(&args, wants_static, std_zlib);
} else {
return false;
}
} else {
return false;
}
if let Some(iopts) = libpng_config(wants_static, "--I_opts") {
let dirs: Vec<_> = iopts.split(" -I").map(|opt| if opt.starts_with("-I") {&opt[2..]} else {opt}).collect();
println!("cargo:include={}", env::join_paths(dirs).unwrap().to_string_lossy());
} else {
fallback_include_path();
}
true
}
fn fallback_include_path() {
println!("cargo:include={}", dunce::canonicalize("vendor").unwrap().display());
}
fn libs_from_args(libs: &str, wants_static: bool, std_zlib: bool) {
let mut args = libs.trim_end().split_whitespace();
while let Some(lib) = args.next() {
if lib.starts_with("-l") {
let lib_name = if lib.len() == 2 {
args.next().expect("-l with argument")
} else {
&lib[2..]
};
if !std_zlib && "z" == lib_name {
continue;
}
let link_static = if lib_name.contains("png") {wants_static} else {
let lib_name = lib_name.to_uppercase();
env::var_os(format!("{}_STATIC", lib_name)).is_some() ||
env::var_os(format!("LIB{}_STATIC", lib_name)).is_some()
};
println!("cargo:rustc-link-lib={}{}", if link_static {"static="} else {""}, lib_name);
}
}
}
fn libpng_config(wants_static: bool, arg: &str) -> Option<String> {
let mut cmd = process::Command::new("libpng-config");
if wants_static {
cmd.arg("--static");
}
cmd.arg(arg);
if let Ok(out) = cmd.output() {
String::from_utf8(out.stdout).ok()
} else {
None
}
}
fn try_pkgconfig(wants_static: bool) -> bool {
let mut pkg = pkg_config::Config::new();
pkg.statik(wants_static);
pkg.atleast_version("1.6"); if let Ok(lib) = pkg.probe("libpng") {
if let Some(path) = lib.include_paths.get(0) {
println!("cargo:include={}", path.display());
} else {
fallback_include_path();
}
if let Some(path) = lib.link_paths.get(0) {
println!("cargo:root={}", path.display());
}
return true;
}
false
}
fn build_static(std_zlib: bool) {
let mut cc = cc::Build::new();
cc.warnings(false);
let vendor = dunce::canonicalize("vendor").unwrap();
let prebuild_conf = vendor.join("scripts/pnglibconf.h.prebuilt");
if !vendor.exists() || !prebuild_conf.exists() {
panic!("libpng-sys: vendor/ dir is missing. Try running `git submodule update --init`");
}
let out_dir = PathBuf::from(env::var_os("OUT_DIR").unwrap());
fs::copy(prebuild_conf, out_dir.join("pnglibconf.h")).unwrap();
let mut includes = vec![vendor];
if let Some(inc) = env::var_os("DEP_Z_INCLUDE") {
includes.push(PathBuf::from(inc));
} else if std_zlib {
if let Ok(libz) = pkg_config::probe_library("z") {
for path in libz.include_paths {
includes.push(path);
}
} else {
println!("cargo:rustc-link-lib=z");
}
}
println!("cargo:root={}", out_dir.display());
includes.push(out_dir);
println!("cargo:include={}", env::join_paths(&includes).unwrap().to_string_lossy());
for path in includes {
cc.include(path);
}
cc
.file("vendor/png.c")
.file("vendor/pngerror.c")
.file("vendor/pngget.c")
.file("vendor/pngmem.c")
.file("vendor/pngpread.c")
.file("vendor/pngread.c")
.file("vendor/pngrio.c")
.file("vendor/pngrtran.c")
.file("vendor/pngrutil.c")
.file("vendor/pngset.c")
.file("vendor/pngtrans.c")
.file("vendor/pngwio.c")
.file("vendor/pngwrite.c")
.file("vendor/pngwtran.c")
.file("vendor/pngwutil.c");
let arch = std::env::var("CARGO_CFG_TARGET_ARCH").unwrap();
if arch == "arm" || arch == "aarch64" {
cc
.file("vendor/arm/arm_init.c")
.file("vendor/arm/filter_neon_intrinsics.c")
.file("vendor/arm/filter_neon.S")
.file("vendor/arm/palette_neon_intrinsics.c");
}
cc.compile("libpng.a");
}