use cbindgen::{Builder, Language};
use std::{
env,
ffi::OsStr,
fs,
path::{Path, PathBuf},
};
const PRE_HEADER: &str = r#"
// Define the `ARCH_X86_X64` constant.
#if defined(MSVC) && defined(_M_AMD64)
# define ARCH_X86_64
#elif (defined(GCC) || defined(__GNUC__) || defined(__clang__)) && defined(__x86_64__)
# define ARCH_X86_64
#endif
// Compatibility with non-Clang compilers.
#if !defined(__has_attribute)
# define __has_attribute(x) 0
#endif
// Compatibility with non-Clang compilers.
#if !defined(__has_declspec_attribute)
# define __has_declspec_attribute(x) 0
#endif
// Define the `DEPRECATED` macro.
#if defined(GCC) || defined(__GNUC__) || __has_attribute(deprecated)
# define DEPRECATED(message) __attribute__((deprecated(message)))
#elif defined(MSVC) || __has_declspec_attribute(deprecated)
# define DEPRECATED(message) __declspec(deprecated(message))
#endif
"#;
#[allow(unused)]
const UNIVERSAL_FEATURE_AS_C_DEFINE: &str = "WASMER_UNIVERSAL_ENABLED";
#[allow(unused)]
const COMPILER_FEATURE_AS_C_DEFINE: &str = "WASMER_COMPILER_ENABLED";
#[allow(unused)]
const WASI_FEATURE_AS_C_DEFINE: &str = "WASMER_WASI_ENABLED";
#[allow(unused)]
const MIDDLEWARES_FEATURE_AS_C_DEFINE: &str = "WASMER_MIDDLEWARES_ENABLED";
#[allow(unused)]
const EMSCRIPTEN_FEATURE_AS_C_DEFINE: &str = "WASMER_EMSCRIPTEN_ENABLED";
#[allow(unused)]
const JSC_FEATURE_AS_C_DEFINE: &str = "WASMER_JSC_BACKEND";
macro_rules! map_feature_as_c_define {
($feature:expr, $c_define:ident, $accumulator:ident) => {
#[cfg(feature = $feature)]
{
use std::fmt::Write;
let _ = write!(
$accumulator,
r#"
// The `{feature}` feature has been enabled for this build.
#define {define}
"#,
feature = $feature,
define = $c_define,
);
}
};
}
fn main() {
if !running_self() {
return;
}
let crate_dir = env::var("CARGO_MANIFEST_DIR").unwrap();
let out_dir = env::var("OUT_DIR").unwrap();
build_wasm_c_api_headers(&crate_dir, &out_dir);
build_inline_c_env_vars();
build_cdylib_link_arg();
}
fn running_self() -> bool {
env::var("DOCS_RS").is_err()
&& env::var("_CBINDGEN_IS_RUNNING").is_err()
&& env::var("WASMER_PUBLISH_SCRIPT_IS_RUNNING").is_err()
}
fn build_wasm_c_api_headers(crate_dir: &str, out_dir: &str) {
let mut crate_header_file = PathBuf::from(crate_dir);
crate_header_file.push("wasmer");
let mut out_header_file = PathBuf::from(out_dir);
out_header_file.push("wasmer");
let mut pre_header = format!(
r#"// The Wasmer C/C++ header file compatible with the [`wasm-c-api`]
// standard API, as `wasm.h` (included here).
//
// This file is automatically generated by `lib/c-api/build.rs` of the
// [`wasmer-c-api`] Rust crate.
//
// # Stability
//
// The [`wasm-c-api`] standard API is a _living_ standard. There is no
// commitment for stability yet. We (Wasmer) will try our best to keep
// backward compatibility as much as possible. Nonetheless, some
// necessary API aren't yet standardized, and as such, we provide a
// custom API, e.g. `wasi_*` types and functions.
//
// The documentation makes it clear whether a function is unstable.
//
// When a type or a function will be deprecated, it will be marked as
// such with the appropriated compiler warning, and will be removed at
// the next release round.
//
// # Documentation
//
// At the time of writing, the [`wasm-c-api`] standard has no
// documentation. This file also does not include inline
// documentation. However, we have made (and we continue to make) an
// important effort to document everything. [See the documentation
// online][documentation]. Please refer to this page for the real
// canonical documentation. It also contains numerous examples.
//
// To generate the documentation locally, run `cargo doc --open` from
// within the [`wasmer-c-api`] Rust crate.
//
// [`wasm-c-api`]: https://github.com/WebAssembly/wasm-c-api
// [`wasmer-c-api`]: https://github.com/wasmerio/wasmer/tree/master/lib/c-api
// [documentation]: https://wasmerio.github.io/wasmer/crates/wasmer_c_api/
#if !defined(WASMER_H_PRELUDE)
#define WASMER_H_PRELUDE
{pre_header}"#,
pre_header = PRE_HEADER
);
map_feature_as_c_define!("jsc", JSC_FEATURE_AS_C_DEFINE, pre_header);
map_feature_as_c_define!("compiler", UNIVERSAL_FEATURE_AS_C_DEFINE, pre_header);
map_feature_as_c_define!("compiler", COMPILER_FEATURE_AS_C_DEFINE, pre_header);
map_feature_as_c_define!("wasi", WASI_FEATURE_AS_C_DEFINE, pre_header);
map_feature_as_c_define!("middlewares", MIDDLEWARES_FEATURE_AS_C_DEFINE, pre_header);
map_feature_as_c_define!("emscripten", EMSCRIPTEN_FEATURE_AS_C_DEFINE, pre_header);
add_wasmer_version(&mut pre_header);
pre_header.push_str(
r#"
#endif // WASMER_H_PRELUDE
//
// OK, here we go. The code below is automatically generated.
//
"#,
);
let guard = "WASMER_H";
{
out_header_file.set_extension("h");
new_builder(Language::C, crate_dir, guard, &pre_header)
.with_include("wasm.h")
.generate()
.expect("Unable to generate C bindings")
.write_to_file(out_header_file.as_path());
crate_header_file.set_extension("h");
fs::copy(out_header_file.as_path(), crate_header_file.as_path())
.expect("Unable to copy the generated C bindings");
}
}
fn add_wasmer_version(pre_header: &mut String) {
use std::fmt::Write;
let _ = write!(
pre_header,
r#"
// This file corresponds to the following Wasmer version.
#define WASMER_VERSION "{full}"
#define WASMER_VERSION_MAJOR {major}
#define WASMER_VERSION_MINOR {minor}
#define WASMER_VERSION_PATCH {patch}
#define WASMER_VERSION_PRE "{pre}"
"#,
full = env!("CARGO_PKG_VERSION"),
major = env!("CARGO_PKG_VERSION_MAJOR"),
minor = env!("CARGO_PKG_VERSION_MINOR"),
patch = env!("CARGO_PKG_VERSION_PATCH"),
pre = env!("CARGO_PKG_VERSION_PRE"),
);
}
fn new_builder(language: Language, crate_dir: &str, include_guard: &str, header: &str) -> Builder {
Builder::new()
.with_config(cbindgen::Config {
sort_by: cbindgen::SortKey::Name,
cpp_compat: true,
..cbindgen::Config::default()
})
.with_language(language)
.with_crate(crate_dir)
.with_include_guard(include_guard)
.with_header(header)
.with_documentation(false)
.with_define("target_family", "windows", "_WIN32")
.with_define("target_arch", "x86_64", "ARCH_X86_64")
.with_define("feature", "universal", UNIVERSAL_FEATURE_AS_C_DEFINE)
.with_define("feature", "compiler", COMPILER_FEATURE_AS_C_DEFINE)
.with_define("feature", "wasi", WASI_FEATURE_AS_C_DEFINE)
.with_define("feature", "emscripten", EMSCRIPTEN_FEATURE_AS_C_DEFINE)
}
fn build_inline_c_env_vars() {
let shared_object_dir = shared_object_dir();
let shared_object_dir = shared_object_dir.as_path().to_string_lossy();
let include_dir = env::var("CARGO_MANIFEST_DIR").unwrap();
println!(
"cargo:rustc-env=INLINE_C_RS_CFLAGS=-I{I} -L{L} -D_DEBUG -D_CRT_SECURE_NO_WARNINGS",
I = include_dir,
L = shared_object_dir.clone(),
);
if let Ok(compiler_engine) = env::var("TEST") {
println!(
"cargo:rustc-env=INLINE_C_RS_TEST={test}",
test = compiler_engine
);
}
println!(
"cargo:rustc-env=INLINE_C_RS_LDFLAGS=-rpath,{shared_object_dir} {shared_object_dir}/{lib}",
shared_object_dir = shared_object_dir,
lib = if cfg!(target_os = "windows") {
"wasmer.dll".to_string()
} else if cfg!(target_vendor = "apple") {
"libwasmer.dylib".to_string()
} else {
let path = format!(
"{shared_object_dir}/{lib}",
shared_object_dir = shared_object_dir,
lib = "libwasmer.so"
);
if Path::new(path.as_str()).exists() {
"libwasmer.so".to_string()
} else {
"libwasmer.a".to_string()
}
}
);
}
fn build_cdylib_link_arg() {
let mut lines = Vec::new();
let os = env::var("CARGO_CFG_TARGET_OS").unwrap();
let env = env::var("CARGO_CFG_TARGET_ENV").unwrap();
let version_major = env::var("CARGO_PKG_VERSION_MAJOR").unwrap();
let version_minor = env::var("CARGO_PKG_VERSION_MINOR").unwrap();
let version_patch = env::var("CARGO_PKG_VERSION_PATCH").unwrap();
let shared_object_dir = shared_object_dir();
match (os.as_str(), env.as_str()) {
("android", _) => {
lines.push("-Wl,-soname,libwasmer.so".to_string());
}
("linux", _) | ("freebsd", _) | ("dragonfly", _) | ("netbsd", _) if env != "musl" => {
lines.push("-Wl,-soname,libwasmer.so".to_string());
}
("macos", _) | ("ios", _) => {
lines.push(format!(
"-Wl,-install_name,@rpath/libwasmer.dylib,-current_version,{x}.{y}.{z},-compatibility_version,{x}",
x = version_major,
y = version_minor,
z = version_patch,
));
}
("windows", "gnu") => {
lines.push(format!(
"-Wl,--out-implib,{}",
shared_object_dir.join("wasmer.dll.a").display()
));
lines.push(format!(
"-Wl,--output-def,{}",
shared_object_dir.join("wasmer.def").display()
));
}
_ => {}
}
for line in lines {
println!("cargo:rustc-cdylib-link-arg={}", line);
}
}
fn shared_object_dir() -> PathBuf {
let mut shared_object_dir = PathBuf::from(env::var("OUT_DIR").unwrap());
assert_eq!(shared_object_dir.file_name(), Some(OsStr::new("out")));
shared_object_dir.pop();
assert!(shared_object_dir
.file_name()
.as_ref()
.unwrap()
.to_string_lossy()
.to_string()
.starts_with("wasmer-c-api"));
shared_object_dir.pop();
assert_eq!(shared_object_dir.file_name(), Some(OsStr::new("build")));
shared_object_dir.pop();
shared_object_dir.pop();
if shared_object_dir.file_name() != Some(OsStr::new("target")) {
let target = env::var("TARGET").unwrap();
if shared_object_dir.file_name() != Some(OsStr::new("llvm-cov-target")) {
assert_eq!(shared_object_dir.file_name(), Some(OsStr::new(&target)));
} else {
shared_object_dir.set_file_name(&target);
}
}
shared_object_dir.push(env::var("PROFILE").unwrap());
shared_object_dir
}