vlc-rs/build.rs

115 lines
3.9 KiB
Rust

fn main() {
#[cfg(target_os = "windows")]
windows::link_vlc();
}
#[cfg(target_os = "windows")]
mod windows {
#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
compile_error!("Only x86 and x86_64 are supported at the moment. Adding support for other architectures should be trivial.");
use std::env;
use std::ffi::OsString;
use std::fs;
use std::path::{Path, PathBuf};
use std::process::Command;
use vswhom::VsFindResult;
pub fn link_vlc() {
let vlc_path = vlc_path();
let out_dir = PathBuf::from(env::var_os("OUT_DIR").unwrap());
let vs = VsFindResult::search().expect("Could not locate Visual Studio");
let vs_exe_path = PathBuf::from(
vs.vs_exe_path
.expect("Could not retrieve executable path for Visual Studio"),
);
generate_lib_from_dll(&out_dir, &vs_exe_path, &vlc_path);
println!("cargo:rustc-link-search=all={}", out_dir.display());
// NOTE: Linking fails with
// ```
// error LNK2019: unresolved external symbol vsnprintf referenced in function _{MangledSymbolName}
// msvcrt.lib(vsnprintf.obj) : error LNK2001: unresolved external symbol vsnprintf
// msvcrt.lib(vsnprintf.obj) : error LNK2001: unresolved external symbol _vsnprintf
// ```
// without this.
// https://stackoverflow.com/a/34230122
println!("cargo:rustc-link-lib=dylib=legacy_stdio_definitions");
}
fn generate_lib_from_dll(out_dir: &Path, vs_exe_path: &Path, vlc_path: &Path) {
// https://wiki.videolan.org/GenerateLibFromDll/
let vs_dumpbin = vs_exe_path.join("dumpbin.exe");
let vs_lib = vs_exe_path.join("lib.exe");
let vlc_def_path = out_dir.join("libvlc.def");
let vlc_import_lib = out_dir.join("vlc.lib");
let libvlc = vlc_path.join("libvlc.dll");
let exports = Command::new(vs_dumpbin)
.current_dir(out_dir)
.arg("/EXPORTS")
.arg(libvlc.display().to_string().trim_end_matches(r"\"))
.output()
.unwrap();
let exports = String::from_utf8(exports.stdout).unwrap();
let mut vlc_def = String::from("EXPORTS\n");
for line in exports.lines() {
if let Some(line) = line.get(26..) {
if line.starts_with("libvlc_") {
vlc_def.push_str(line);
vlc_def.push_str("\r\n");
}
}
}
fs::write(&vlc_def_path, vlc_def.into_bytes()).unwrap();
// FIXME: Handle paths with spaces in them.
Command::new(vs_lib)
.current_dir(out_dir)
.arg("/NOLOGO")
.args(&[
format!(
r#"/DEF:{}"#,
vlc_def_path.display().to_string().trim_end_matches(r"\")
),
format!(
r#"/OUT:{}"#,
vlc_import_lib.display().to_string().trim_end_matches(r"\")
),
format!(
"/MACHINE:{}",
match target_arch().as_str() {
"x86" => "x86",
"x86_64" => "x64",
_ => unreachable!(),
}
),
])
.spawn()
.unwrap();
}
fn vlc_path() -> PathBuf {
#[allow(unused_assignments)]
let arch_path: Option<OsString> = match target_arch().as_str() {
"x86" => env::var_os("VLC_LIB_DIR_X86"),
"x86_64" => env::var_os("VLC_LIB_DIR_X86_64"),
_ => unreachable!(),
};
arch_path
.or_else(|| env::var_os("VLC_LIB_DIR"))
.map(PathBuf::from)
.expect("VLC_LIB_DIR not set")
}
fn target_arch() -> String {
env::var("CARGO_CFG_TARGET_ARCH").unwrap()
}
}