mirror of https://github.com/http-rs/http-types
70 lines
2.0 KiB
Rust
70 lines
2.0 KiB
Rust
use std::env;
|
|
use std::fs;
|
|
use std::path::Path;
|
|
use std::process::{Command, ExitStatus, Stdio};
|
|
|
|
// This build script is copied from
|
|
// [anyhow](https://github.com/dtolnay/anyhow/blob/master/build.rs),
|
|
// and is a type of feature detection to determine if the current rust
|
|
// toolchain has backtraces available.
|
|
//
|
|
// It exercises the surface area that we expect of the std Backtrace
|
|
// type. If the current toolchain is able to compile it, we enable a
|
|
// backtrace compiler configuration flag in http-types. We then
|
|
// conditionally require the compiler feature in src/lib.rs with
|
|
// `#![cfg_attr(backtrace, feature(backtrace))]`
|
|
// and gate our backtrace code behind `#[cfg(backtrace)]`
|
|
|
|
const PROBE: &str = r#"
|
|
#![feature(backtrace)]
|
|
#![allow(dead_code)]
|
|
|
|
use std::backtrace::{Backtrace, BacktraceStatus};
|
|
use std::error::Error;
|
|
use std::fmt::{self, Display};
|
|
|
|
#[derive(Debug)]
|
|
struct E;
|
|
|
|
impl Display for E {
|
|
fn fmt(&self, _formatter: &mut fmt::Formatter) -> fmt::Result {
|
|
unimplemented!()
|
|
}
|
|
}
|
|
|
|
impl Error for E {
|
|
fn backtrace(&self) -> Option<&Backtrace> {
|
|
let backtrace = Backtrace::capture();
|
|
match backtrace.status() {
|
|
BacktraceStatus::Captured | BacktraceStatus::Disabled | _ => {}
|
|
}
|
|
unimplemented!()
|
|
}
|
|
}
|
|
"#;
|
|
|
|
fn main() {
|
|
match compile_probe() {
|
|
Some(status) if status.success() => println!("cargo:rustc-cfg=backtrace"),
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
fn compile_probe() -> Option<ExitStatus> {
|
|
let rustc = env::var_os("RUSTC")?;
|
|
let out_dir = env::var_os("OUT_DIR")?;
|
|
let probefile = Path::new(&out_dir).join("probe.rs");
|
|
fs::write(&probefile, PROBE).ok()?;
|
|
Command::new(rustc)
|
|
.stderr(Stdio::null())
|
|
.arg("--edition=2018")
|
|
.arg("--crate-name=http_types_build")
|
|
.arg("--crate-type=lib")
|
|
.arg("--emit=metadata")
|
|
.arg("--out-dir")
|
|
.arg(out_dir)
|
|
.arg(probefile)
|
|
.status()
|
|
.ok()
|
|
}
|