Support defining custom lua include and lib pathes

build.rs

@@ -1,47 +1,69 @@
 use std::env;
-use std::io;
+use std::fs::File;
-use std::path::PathBuf;
+use std::io::{BufRead, BufReader, Error, ErrorKind, Result};
+use std::ops::Bound;
+use std::path::{Path, PathBuf};
 use std::process::Command;
 
 trait CommandExt {
-    fn execute(&mut self) -> io::Result<()>;
+    fn execute(&mut self) -> Result<()>;
 }
 
 impl CommandExt for Command {
     /// Execute the command and return an error if it exited with a failure status.
-    fn execute(&mut self) -> io::Result<()> {
+    fn execute(&mut self) -> Result<()> {
-        self.status().map(|_| ()).map_err(|_| {
+        self.status()
-            io::Error::new(
+            .and_then(|status| {
-                io::ErrorKind::Other,
+                if status.success() {
-                format!(
+                    Ok(())
-                    "The command\n\
+                } else {
-                     \t{:?}\n\
+                    Err(Error::new(ErrorKind::Other, "non-zero exit code"))
-                     did not run successfully.",
+                }
-                    self
+            })
-                ),
+            .map_err(|_| {
+                Error::new(
+                    ErrorKind::Other,
+                    format!("The command {:?} did not run successfully.", self),
                 )
             })
     }
 }
 
-fn main() {
+fn use_custom_lua<S: AsRef<str>>(include_dir: &S, lib_dir: &S, lua_lib: &S) -> Result<String> {
-    let lua = pkg_config::Config::new()
+    let mut version_found = String::new();
-        .atleast_version("5.1")
-        .probe("lua")
-        .unwrap();
 
+    // Find LUA_VERSION_NUM
+    let mut lua_h_path = PathBuf::from(include_dir.as_ref());
+    lua_h_path.push("lua.h");
+    let f = File::open(lua_h_path)?;
+    let reader = BufReader::new(f);
+    for line in reader.lines() {
+        let line = line?;
+        let parts = line.split_whitespace().collect::<Vec<_>>();
+        if parts.len() == 3 && parts[1] == "LUA_VERSION_NUM" {
+            version_found = parts[2].to_string();
+        }
+    }
+
+    println!("cargo:rustc-link-search=native={}", lib_dir.as_ref());
+    println!("cargo:rustc-link-lib={}", lua_lib.as_ref());
+
+    Ok(version_found)
+}
+
+fn build_glue<P: AsRef<Path> + std::fmt::Debug>(include_paths: &[P]) {
     let build_dir = PathBuf::from(env::var_os("OUT_DIR").unwrap());
 
     // Ensure the presence of glue.rs
-    if !build_dir.join("glue.rs").exists() {
+    // if build_dir.join("glue.rs").exists() {
+    //     return;
+    // }
+
     let mut config = cc::Build::new();
 
-        for path in lua.include_paths {
+    for path in include_paths {
         config.include(path);
     }
-        for (k, v) in lua.defines {
-            config.define(&k, v.as_ref().map(|x| x.as_str()));
-        }
 
     // Compile and run glue.c
     let glue = build_dir.join("glue");
@@ -59,5 +81,29 @@ fn main() {
         .arg(build_dir.join("glue.rs"))
         .execute()
         .unwrap();
-    }
+}
+
+fn main() {
+    let include_dir = env::var("LUA_INCLUDE_DIR").unwrap_or(String::new());
+    let lib_dir = env::var("LUA_LIB_DIR").unwrap_or(String::new());
+    let lua_lib = env::var("LUA_LIB_NAME").unwrap_or(String::new());
+
+    println!("cargo:rerun-if-env-changed=LUA_INCLUDE_DIR");
+    println!("cargo:rerun-if-env-changed=LUA_LIB_DIR");
+    println!("cargo:rerun-if-env-changed=LUA_LIB_NAME");
+
+    if include_dir != "" && lib_dir != "" && lua_lib != "" {
+        let _version = use_custom_lua(&include_dir, &lib_dir, &lua_lib).unwrap();
+        build_glue(&[include_dir]);
+        return;
+    }
+
+    // Find lua via pkg-config
+
+    let lua = pkg_config::Config::new()
+        .range_version((Bound::Included("5.3"), Bound::Excluded("5.4")))
+        .probe("lua")
+        .unwrap();
+
+    build_glue(&lua.include_paths);
 }