fish-shell/build.rs
Mahmoud Al-Qudsi d07d0170ad build.rs: also declare cfgs when we run into a warning
e.g. gettext is found but can't be used
2024-05-21 13:34:24 -05:00

231 lines
8.8 KiB
Rust

#![allow(clippy::uninlined_format_args)]
use rsconf::{LinkType, Target};
use std::env;
use std::error::Error;
use std::path::{Path, PathBuf};
fn main() {
setup_paths();
// Add our default to enable tools that don't go through CMake, like "cargo test" and the
// language server.
// FISH_BUILD_DIR is set by CMake, if we are using it.
// OUT_DIR is set by Cargo when the build script is running (not compiling)
let default_build_dir = env::var("OUT_DIR").unwrap();
let build_dir = option_env!("FISH_BUILD_DIR").unwrap_or(&default_build_dir);
rsconf::set_env_value("FISH_BUILD_DIR", build_dir);
// We need to canonicalize (i.e. realpath) the manifest dir because we want to be able to
// compare it directly as a string at runtime.
rsconf::set_env_value(
"CARGO_MANIFEST_DIR",
std::fs::canonicalize(env!("CARGO_MANIFEST_DIR"))
.unwrap()
.as_path()
.to_str()
.unwrap(),
);
// Per https://doc.rust-lang.org/cargo/reference/build-scripts.html#inputs-to-the-build-script,
// the source directory is the current working directory of the build script
rsconf::set_env_value(
"FISH_BUILD_VERSION",
&get_version(&env::current_dir().unwrap()),
);
rsconf::rebuild_if_path_changed("src/libc.c");
cc::Build::new()
.file("src/libc.c")
.include(build_dir)
.compile("flibc.a");
let mut build = cc::Build::new();
// Add to the default library search path
build.flag_if_supported("-L/usr/local/lib/");
rsconf::add_library_search_path("/usr/local/lib");
let mut target = Target::new_from(build).unwrap();
// Keep verbose mode on until we've ironed out rust build script stuff
target.set_verbose(true);
detect_cfgs(&mut target);
}
/// Check target system support for certain functionality dynamically when the build is invoked,
/// without their having to be explicitly enabled in the `cargo build --features xxx` invocation.
///
/// We are using [`rsconf::enable_cfg()`] instead of [`rsconf::enable_feature()`] as rust features
/// should be used for things that a user can/would reasonably enable or disable to tweak or coerce
/// behavior, but here we are testing for whether or not things are supported altogether.
///
/// This can be used to enable features that we check for and conditionally compile according to in
/// our own codebase, but [can't be used to pull in dependencies](0) even if they're gated (in
/// `Cargo.toml`) behind a feature we just enabled.
///
/// [0]: https://github.com/rust-lang/cargo/issues/5499
#[rustfmt::skip]
fn detect_cfgs(target: &mut Target) {
for (name, handler) in [
// Ignore the first entry, it just sets up the type inference. Model new entries after the
// second line.
(
"",
&(|_: &Target| Ok(false)) as &dyn Fn(&Target) -> Result<bool, Box<dyn Error>>,
),
("bsd", &detect_bsd),
("gettext", &have_gettext),
// See if libc supports the thread-safe localeconv_l(3) alternative to localeconv(3).
("localeconv_l", &|target| {
Ok(target.has_symbol("localeconv_l"))
}),
("FISH_USE_POSIX_SPAWN", &|target| {
Ok(target.has_header("spawn.h"))
}),
("HAVE_PIPE2", &|target| {
Ok(target.has_symbol("pipe2"))
}),
("HAVE_EVENTFD", &|target| {
Ok(target.has_header("sys/eventfd.h"))
}),
("HAVE_WAITSTATUS_SIGNAL_RET", &|target| {
Ok(target.r#if("WEXITSTATUS(0x007f) == 0x7f", &["sys/wait.h"]))
}),
] {
match handler(target) {
Err(e) => {
rsconf::warn!("{}: {}", name, e);
rsconf::declare_cfg(name, false);
},
Ok(enabled) => rsconf::declare_cfg(name, enabled),
}
}
}
/// Detect if we're being compiled for a BSD-derived OS, allowing targeting code conditionally with
/// `#[cfg(bsd)]`.
///
/// Rust offers fine-grained conditional compilation per-os for the popular operating systems, but
/// doesn't necessarily include less-popular forks nor does it group them into families more
/// specific than "windows" vs "unix" so we can conditionally compile code for BSD systems.
fn detect_bsd(_: &Target) -> Result<bool, Box<dyn Error>> {
// Instead of using `uname`, we can inspect the TARGET env variable set by Cargo. This lets us
// support cross-compilation scenarios.
let mut target = std::env::var("TARGET").unwrap();
if !target.chars().all(|c| c.is_ascii_lowercase()) {
target = target.to_ascii_lowercase();
}
let is_bsd = target.ends_with("bsd") || target.ends_with("dragonfly");
#[cfg(any(
target_os = "dragonfly",
target_os = "freebsd",
target_os = "netbsd",
target_os = "openbsd",
))]
assert!(is_bsd, "Target incorrectly detected as not BSD!");
Ok(is_bsd)
}
/// Detect libintl/gettext and its needed symbols to enable internationalization/localization
/// support.
fn have_gettext(target: &Target) -> Result<bool, Box<dyn Error>> {
// The following script correctly detects and links against gettext, but so long as we are using
// C++ and generate a static library linked into the C++ binary via CMake, we need to account
// for the CMake option WITH_GETTEXT being explicitly disabled.
rsconf::rebuild_if_env_changed("CMAKE_WITH_GETTEXT");
if let Some(with_gettext) = std::env::var_os("CMAKE_WITH_GETTEXT") {
if with_gettext.eq_ignore_ascii_case("0") {
return Ok(false);
}
}
// In order for fish to correctly operate, we need some way of notifying libintl to invalidate
// its localizations when the locale environment variables are modified. Without the libintl
// symbol _nl_msg_cat_cntr, we cannot use gettext even if we find it.
let mut libraries = Vec::new();
let mut found = 0;
let symbols = ["gettext", "_nl_msg_cat_cntr"];
for symbol in &symbols {
// Historically, libintl was required in order to use gettext() and co, but that
// functionality was subsumed by some versions of libc.
if target.has_symbol(symbol) {
// No need to link anything special for this symbol
found += 1;
continue;
}
for library in ["intl", "gettextlib"] {
if target.has_symbol_in(symbol, &[library]) {
libraries.push(library);
found += 1;
continue;
}
}
}
match found {
0 => Ok(false),
1 => Err(format!("gettext found but cannot be used without {}", symbols[1]).into()),
_ => {
rsconf::link_libraries(&libraries, LinkType::Default);
Ok(true)
}
}
}
fn setup_paths() {
fn get_path(name: &str, default: &str, onvar: PathBuf) -> PathBuf {
let mut var = PathBuf::from(env::var(name).unwrap_or(default.to_string()));
if var.is_relative() {
var = onvar.join(var);
}
var
}
let prefix = PathBuf::from(env::var("PREFIX").unwrap_or("/usr/local".to_string()));
if prefix.is_relative() {
panic!("Can't have relative prefix");
}
rsconf::rebuild_if_env_changed("PREFIX");
rsconf::set_env_value("PREFIX", prefix.to_str().unwrap());
let datadir = get_path("DATADIR", "share/", prefix.clone());
rsconf::set_env_value("DATADIR", datadir.to_str().unwrap());
rsconf::rebuild_if_env_changed("DATADIR");
let bindir = get_path("BINDIR", "bin/", prefix.clone());
rsconf::set_env_value("BINDIR", bindir.to_str().unwrap());
rsconf::rebuild_if_env_changed("BINDIR");
let sysconfdir = get_path("SYSCONFDIR", "etc/", datadir.clone());
rsconf::set_env_value("SYSCONFDIR", sysconfdir.to_str().unwrap());
rsconf::rebuild_if_env_changed("SYSCONFDIR");
let localedir = get_path("LOCALEDIR", "locale/", datadir.clone());
rsconf::set_env_value("LOCALEDIR", localedir.to_str().unwrap());
rsconf::rebuild_if_env_changed("LOCALEDIR");
let docdir = get_path("DOCDIR", "doc/fish", datadir.clone());
rsconf::set_env_value("DOCDIR", docdir.to_str().unwrap());
rsconf::rebuild_if_env_changed("DOCDIR");
}
fn get_version(src_dir: &Path) -> String {
use std::fs::read_to_string;
use std::process::Command;
if let Ok(var) = std::env::var("FISH_BUILD_VERSION") {
return var;
}
let path = PathBuf::from(src_dir).join("version");
if let Ok(strver) = read_to_string(path) {
return strver.to_string();
}
let args = &["describe", "--always", "--dirty=-dirty"];
if let Ok(output) = Command::new("git").args(args).output() {
let rev = String::from_utf8_lossy(&output.stdout).trim().to_string();
if !rev.is_empty() {
return rev;
}
}
"unknown".to_string()
}