more docs for the build.rs file

examples/build.rs

@@ -8,21 +8,31 @@ fn main() {
     let manifest_path = PathBuf::from(&manifest_dir);
     let lib_cfg_dir = "../lib/cfg/csp";
     let libcsp_path = "../lib/libcsp";
+
+    // This helper structure will take care of the majority of work to compile libcsp using the
+    // cc crate.
     let mut csp_builder = Builder::new(PathBuf::from(libcsp_path), PathBuf::from(&out_dir));
+    // A lot of spam we are not interested in usually.
     csp_builder.compiler_warnings = false;
+
     // We always re-generate the header file.
     generate_autoconf_header_file(manifest_path.clone(), &csp_builder.cfg)
         .expect("generating header file failed");
+
     // Copy the file to lib/csp/cfg as well for binding generation.
     std::fs::copy(
         manifest_path.join("autoconfig.h"),
         PathBuf::from(&lib_cfg_dir).join("autoconfig.h"),
     )
     .expect("copying autoconfig.h failed");
+
+    // This file is required for the compile-time configuration of libcsp-rust.
     csp_builder
         .generate_autoconf_rust_file(manifest_path)
         .expect("generating autoconfig.rs failed");
+
     csp_builder.compile().expect("compiling libcsp failed");
+
     // If we change the libcsp build configuration, we need to re-run the build.
     println!("cargo::rerun-if-changed=build.rs");
 }