use pkg-config to find Linux libraries (#2)

Author: Be-ing

webrtc-sys/Cargo.toml

@@ -22,5 +22,8 @@ cxx-build = "1.0"
 glob = "0.3"
 cc = "1.0"
 
+[target.'cfg(target_os = "linux")'.build-dependencies]
+pkg-config = "0.3.22"
+
 [dev-dependencies]
 env_logger = "0.10"

webrtc-sys/build.rs

@@ -155,13 +155,21 @@ fn main() {
             println!("cargo:rustc-link-lib=dylib=pthread");
             println!("cargo:rustc-link-lib=dylib=m");
 
-            println!("cargo:rustc-link-lib=dylib=glib-2.0");
-            println!("cargo:rustc-link-lib=dylib=gobject-2.0");
-            println!("cargo:rustc-link-lib=dylib=gio-2.0");
-            println!("cargo:rustc-link-lib=dylib=drm");
-            println!("cargo:rustc-link-lib=dylib=gbm");
+            if std::env::var("LK_CUSTOM_WEBRTC").is_ok() {
+                for lib_name in ["glib-2.0", "gobject-2.0", "gio-2.0"] {
+                    let lib = pkg_config::probe_library(lib_name).unwrap();
+                    builder.includes(lib.include_paths);
+                }
+            } else {
+                println!("cargo:rustc-link-lib=dylib=glib-2.0");
+                println!("cargo:rustc-link-lib=dylib=gobject-2.0");
+                println!("cargo:rustc-link-lib=dylib=gio-2.0");
+                add_gio_headers(&mut builder);
+            }
 
-            add_gio_headers(&mut builder);
+            for lib_name in ["libdrm", "gbm"] {
+                pkg_config::probe_library(lib_name).unwrap();
+            }
 
             match target_arch.as_str() {
                 "x86_64" => {