style: Remove the ability to build Gecko without the bindgen feature.

This is not used for anything, as far as I can tell.

Differential Revision: https://phabricator.services.mozilla.com/D38584

1 files changed, 343 insertions, 395 deletions

diff --git a/components/style/build_gecko.rs b/components/style/build_gecko.rs
index e51ba6bfa3f..86d2098d063 100644
--- a/components/style/build_gecko.rs
+++ b/components/style/build_gecko.rs
@@ -2,458 +2,406 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-mod common {
-    use std::env;
-    use std::path::PathBuf;
-
-    lazy_static! {
-        pub static ref OUTDIR_PATH: PathBuf =
-            PathBuf::from(env::var_os("OUT_DIR").unwrap()).join("gecko");
-    }
+use super::PYTHON;
+use bindgen::{Builder, CodegenConfig};
+use regex::Regex;
+use std::cmp;
+use std::collections::HashSet;
+use std::env;
+use std::fs::{self, File};
+use std::io::{Read, Write};
+use std::path::{Path, PathBuf};
+use std::process::{exit, Command};
+use std::slice;
+use std::sync::Mutex;
+use std::time::SystemTime;
+use toml;
+use toml::value::Table;
+
+lazy_static! {
+    static ref OUTDIR_PATH: PathBuf = PathBuf::from(env::var_os("OUT_DIR").unwrap()).join("gecko");
 }
 
-#[cfg(feature = "bindgen")]
-mod bindings {
-    use super::super::PYTHON;
-    use super::common::*;
-    use bindgen::{Builder, CodegenConfig};
-    use regex::Regex;
-    use std::cmp;
-    use std::collections::HashSet;
-    use std::env;
-    use std::fs::{self, File};
-    use std::io::{Read, Write};
-    use std::path::{Path, PathBuf};
-    use std::process::{exit, Command};
-    use std::slice;
-    use std::sync::Mutex;
-    use std::time::SystemTime;
-    use toml;
-    use toml::value::Table;
-
-    const STRUCTS_FILE: &'static str = "structs.rs";
-
-    fn read_config(path: &PathBuf) -> Table {
-        println!("cargo:rerun-if-changed={}", path.to_str().unwrap());
-        update_last_modified(&path);
-
-        let mut contents = String::new();
-        File::open(path)
-            .expect("Failed to open config file")
-            .read_to_string(&mut contents)
-            .expect("Failed to read config file");
-        match toml::from_str::<Table>(&contents) {
-            Ok(result) => result,
-            Err(e) => panic!("Failed to parse config file: {}", e),
-        }
-    }
-
-    lazy_static! {
-        static ref CONFIG: Table = {
-            // Load Gecko's binding generator config from the source tree.
-            let path = PathBuf::from(env::var_os("MOZ_SRC").unwrap())
-                .join("layout/style/ServoBindings.toml");
-            read_config(&path)
-        };
-        static ref BUILD_CONFIG: Table = {
-            // Load build-specific config overrides.
-            let path = PathBuf::from(env::var_os("MOZ_TOPOBJDIR").unwrap())
-                .join("layout/style/bindgen.toml");
-            read_config(&path)
-        };
-        static ref INCLUDE_RE: Regex = Regex::new(r#"#include\s*"(.+?)""#).unwrap();
-        static ref DISTDIR_PATH: PathBuf = {
-            let path = PathBuf::from(env::var_os("MOZ_DIST").unwrap());
-            if !path.is_absolute() || !path.is_dir() {
-                panic!("MOZ_DIST must be an absolute directory, was: {}", path.display());
-            }
-            path
-        };
-        static ref SEARCH_PATHS: Vec<PathBuf> = vec![
-            DISTDIR_PATH.join("include"),
-            DISTDIR_PATH.join("include/nspr"),
-        ];
-        static ref ADDED_PATHS: Mutex<HashSet<PathBuf>> = Mutex::new(HashSet::new());
-        static ref LAST_MODIFIED: Mutex<SystemTime> =
-            Mutex::new(get_modified_time(&env::current_exe().unwrap())
-                       .expect("Failed to get modified time of executable"));
-    }
+const STRUCTS_FILE: &'static str = "structs.rs";
 
-    fn get_modified_time(file: &Path) -> Option<SystemTime> {
-        file.metadata().and_then(|m| m.modified()).ok()
-    }
+fn read_config(path: &PathBuf) -> Table {
+    println!("cargo:rerun-if-changed={}", path.to_str().unwrap());
+    update_last_modified(&path);
 
-    fn update_last_modified(file: &Path) {
-        let modified = get_modified_time(file).expect("Couldn't get file modification time");
-        let mut last_modified = LAST_MODIFIED.lock().unwrap();
-        *last_modified = cmp::max(modified, *last_modified);
+    let mut contents = String::new();
+    File::open(path)
+        .expect("Failed to open config file")
+        .read_to_string(&mut contents)
+        .expect("Failed to read config file");
+    match toml::from_str::<Table>(&contents) {
+        Ok(result) => result,
+        Err(e) => panic!("Failed to parse config file: {}", e),
     }
+}
 
-    fn search_include(name: &str) -> Option<PathBuf> {
-        for path in SEARCH_PATHS.iter() {
-            let file = path.join(name);
-            if file.is_file() {
-                update_last_modified(&file);
-                return Some(file);
-            }
+lazy_static! {
+    static ref CONFIG: Table = {
+        // Load Gecko's binding generator config from the source tree.
+        let path = PathBuf::from(env::var_os("MOZ_SRC").unwrap())
+            .join("layout/style/ServoBindings.toml");
+        read_config(&path)
+    };
+    static ref BUILD_CONFIG: Table = {
+        // Load build-specific config overrides.
+        let path = PathBuf::from(env::var_os("MOZ_TOPOBJDIR").unwrap())
+            .join("layout/style/bindgen.toml");
+        read_config(&path)
+    };
+    static ref INCLUDE_RE: Regex = Regex::new(r#"#include\s*"(.+?)""#).unwrap();
+    static ref DISTDIR_PATH: PathBuf = {
+        let path = PathBuf::from(env::var_os("MOZ_DIST").unwrap());
+        if !path.is_absolute() || !path.is_dir() {
+            panic!("MOZ_DIST must be an absolute directory, was: {}", path.display());
         }
-        None
-    }
+        path
+    };
+    static ref SEARCH_PATHS: Vec<PathBuf> = vec![
+        DISTDIR_PATH.join("include"),
+        DISTDIR_PATH.join("include/nspr"),
+    ];
+    static ref ADDED_PATHS: Mutex<HashSet<PathBuf>> = Mutex::new(HashSet::new());
+    static ref LAST_MODIFIED: Mutex<SystemTime> =
+        Mutex::new(get_modified_time(&env::current_exe().unwrap())
+                   .expect("Failed to get modified time of executable"));
+}
 
-    fn add_headers_recursively(path: PathBuf, added_paths: &mut HashSet<PathBuf>) {
-        if added_paths.contains(&path) {
-            return;
-        }
-        let mut file = File::open(&path).unwrap();
-        let mut content = String::new();
-        file.read_to_string(&mut content).unwrap();
-        added_paths.insert(path);
-        // Find all includes and add them recursively
-        for cap in INCLUDE_RE.captures_iter(&content) {
-            if let Some(path) = search_include(cap.get(1).unwrap().as_str()) {
-                add_headers_recursively(path, added_paths);
-            }
+fn get_modified_time(file: &Path) -> Option<SystemTime> {
+    file.metadata().and_then(|m| m.modified()).ok()
+}
+
+fn update_last_modified(file: &Path) {
+    let modified = get_modified_time(file).expect("Couldn't get file modification time");
+    let mut last_modified = LAST_MODIFIED.lock().unwrap();
+    *last_modified = cmp::max(modified, *last_modified);
+}
+
+fn search_include(name: &str) -> Option<PathBuf> {
+    for path in SEARCH_PATHS.iter() {
+        let file = path.join(name);
+        if file.is_file() {
+            update_last_modified(&file);
+            return Some(file);
         }
     }
+    None
+}
 
-    fn add_include(name: &str) -> String {
-        let mut added_paths = ADDED_PATHS.lock().unwrap();
-        let file = search_include(name).expect("Include not found!");
-        let result = String::from(file.to_str().unwrap());
-        add_headers_recursively(file, &mut *added_paths);
-        result
+fn add_headers_recursively(path: PathBuf, added_paths: &mut HashSet<PathBuf>) {
+    if added_paths.contains(&path) {
+        return;
     }
-
-    trait BuilderExt {
-        fn get_initial_builder() -> Builder;
-        fn include<T: Into<String>>(self, file: T) -> Builder;
+    let mut file = File::open(&path).unwrap();
+    let mut content = String::new();
+    file.read_to_string(&mut content).unwrap();
+    added_paths.insert(path);
+    // Find all includes and add them recursively
+    for cap in INCLUDE_RE.captures_iter(&content) {
+        if let Some(path) = search_include(cap.get(1).unwrap().as_str()) {
+            add_headers_recursively(path, added_paths);
+        }
     }
+}
 
-    impl BuilderExt for Builder {
-        fn get_initial_builder() -> Builder {
-            use bindgen::RustTarget;
-
-            // Disable rust unions, because we replace some types inside of
-            // them.
-            let mut builder = Builder::default()
-                .rust_target(RustTarget::Stable_1_25)
-                .disable_untagged_union();
-
-            let rustfmt_path = env::var_os("RUSTFMT")
-                // This can be replaced with
-                // > .filter(|p| !p.is_empty()).map(PathBuf::from)
-                // once we can use 1.27+.
-                .and_then(|p| {
-                    if p.is_empty() {
-                        None
-                    } else {
-                        Some(PathBuf::from(p))
-                    }
-                });
-            if let Some(path) = rustfmt_path {
-                builder = builder.with_rustfmt(path);
-            }
+fn add_include(name: &str) -> String {
+    let mut added_paths = ADDED_PATHS.lock().unwrap();
+    let file = search_include(name).expect("Include not found!");
+    let result = String::from(file.to_str().unwrap());
+    add_headers_recursively(file, &mut *added_paths);
+    result
+}
 
-            for dir in SEARCH_PATHS.iter() {
-                builder = builder.clang_arg("-I").clang_arg(dir.to_str().unwrap());
-            }
+trait BuilderExt {
+    fn get_initial_builder() -> Builder;
+    fn include<T: Into<String>>(self, file: T) -> Builder;
+}
 
-            builder = builder.include(add_include("mozilla-config.h"));
+impl BuilderExt for Builder {
+    fn get_initial_builder() -> Builder {
+        use bindgen::RustTarget;
+
+        // Disable rust unions, because we replace some types inside of
+        // them.
+        let mut builder = Builder::default()
+            .rust_target(RustTarget::Stable_1_25)
+            .disable_untagged_union();
+
+        let rustfmt_path = env::var_os("RUSTFMT")
+            // This can be replaced with
+            // > .filter(|p| !p.is_empty()).map(PathBuf::from)
+            // once we can use 1.27+.
+            .and_then(|p| {
+                if p.is_empty() {
+                    None
+                } else {
+                    Some(PathBuf::from(p))
+                }
+            });
+        if let Some(path) = rustfmt_path {
+            builder = builder.with_rustfmt(path);
+        }
 
-            if env::var("CARGO_FEATURE_GECKO_DEBUG").is_ok() {
-                builder = builder.clang_arg("-DDEBUG=1").clang_arg("-DJS_DEBUG=1");
-            }
+        for dir in SEARCH_PATHS.iter() {
+            builder = builder.clang_arg("-I").clang_arg(dir.to_str().unwrap());
+        }
 
-            let build_config = BUILD_CONFIG["build"]
-                .as_table()
-                .expect("Malformed config file");
-            let extra_bindgen_flags = build_config["args"].as_array().unwrap().as_slice();
-            for item in extra_bindgen_flags.iter() {
-                builder = builder.clang_arg(item.as_str().expect("Expect string in list"));
-            }
+        builder = builder.include(add_include("mozilla-config.h"));
 
-            builder
+        if env::var("CARGO_FEATURE_GECKO_DEBUG").is_ok() {
+            builder = builder.clang_arg("-DDEBUG=1").clang_arg("-DJS_DEBUG=1");
         }
-        fn include<T: Into<String>>(self, file: T) -> Builder {
-            self.clang_arg("-include").clang_arg(file)
+
+        let build_config = BUILD_CONFIG["build"]
+            .as_table()
+            .expect("Malformed config file");
+        let extra_bindgen_flags = build_config["args"].as_array().unwrap().as_slice();
+        for item in extra_bindgen_flags.iter() {
+            builder = builder.clang_arg(item.as_str().expect("Expect string in list"));
         }
-    }
 
-    struct Fixup {
-        pat: String,
-        rep: String,
+        builder
+    }
+    fn include<T: Into<String>>(self, file: T) -> Builder {
+        self.clang_arg("-include").clang_arg(file)
     }
+}
 
-    fn write_binding_file(builder: Builder, file: &str, fixups: &[Fixup]) {
-        let out_file = OUTDIR_PATH.join(file);
-        if let Some(modified) = get_modified_time(&out_file) {
-            // Don't generate the file if nothing it depends on was modified.
-            let last_modified = LAST_MODIFIED.lock().unwrap();
-            if *last_modified <= modified {
-                return;
-            }
-        }
-        let command_line_opts = builder.command_line_flags();
-        let result = builder.generate();
-        let mut result = match result {
-            Ok(bindings) => bindings.to_string(),
-            Err(_) => {
-                panic!(
-                    "Failed to generate bindings, flags: {:?}",
-                    command_line_opts
-                );
-            },
-        };
-
-        for fixup in fixups.iter() {
-            result = Regex::new(&fixup.pat)
-                .unwrap()
-                .replace_all(&result, &*fixup.rep)
-                .into_owned()
-                .into();
+struct Fixup {
+    pat: String,
+    rep: String,
+}
+
+fn write_binding_file(builder: Builder, file: &str, fixups: &[Fixup]) {
+    let out_file = OUTDIR_PATH.join(file);
+    if let Some(modified) = get_modified_time(&out_file) {
+        // Don't generate the file if nothing it depends on was modified.
+        let last_modified = LAST_MODIFIED.lock().unwrap();
+        if *last_modified <= modified {
+            return;
         }
-        let bytes = result.into_bytes();
-        File::create(&out_file)
-            .unwrap()
-            .write_all(&bytes)
-            .expect("Unable to write output");
     }
+    let command_line_opts = builder.command_line_flags();
+    let result = builder.generate();
+    let mut result = match result {
+        Ok(bindings) => bindings.to_string(),
+        Err(_) => {
+            panic!(
+                "Failed to generate bindings, flags: {:?}",
+                command_line_opts
+            );
+        },
+    };
 
-    struct BuilderWithConfig<'a> {
-        builder: Builder,
-        config: &'a Table,
-        used_keys: HashSet<&'static str>,
+    for fixup in fixups.iter() {
+        result = Regex::new(&fixup.pat)
+            .unwrap()
+            .replace_all(&result, &*fixup.rep)
+            .into_owned()
+            .into();
     }
-    impl<'a> BuilderWithConfig<'a> {
-        fn new(builder: Builder, config: &'a Table) -> Self {
-            BuilderWithConfig {
-                builder,
-                config,
-                used_keys: HashSet::new(),
-            }
-        }
+    let bytes = result.into_bytes();
+    File::create(&out_file)
+        .unwrap()
+        .write_all(&bytes)
+        .expect("Unable to write output");
+}
 
-        fn handle_list<F>(self, key: &'static str, func: F) -> BuilderWithConfig<'a>
-        where
-            F: FnOnce(Builder, slice::Iter<'a, toml::Value>) -> Builder,
-        {
-            let mut builder = self.builder;
-            let config = self.config;
-            let mut used_keys = self.used_keys;
-            if let Some(list) = config.get(key) {
-                used_keys.insert(key);
-                builder = func(builder, list.as_array().unwrap().as_slice().iter());
-            }
-            BuilderWithConfig {
-                builder,
-                config,
-                used_keys,
-            }
-        }
-        fn handle_items<F>(self, key: &'static str, mut func: F) -> BuilderWithConfig<'a>
-        where
-            F: FnMut(Builder, &'a toml::Value) -> Builder,
-        {
-            self.handle_list(key, |b, iter| iter.fold(b, |b, item| func(b, item)))
-        }
-        fn handle_str_items<F>(self, key: &'static str, mut func: F) -> BuilderWithConfig<'a>
-        where
-            F: FnMut(Builder, &'a str) -> Builder,
-        {
-            self.handle_items(key, |b, item| func(b, item.as_str().unwrap()))
-        }
-        fn handle_table_items<F>(self, key: &'static str, mut func: F) -> BuilderWithConfig<'a>
-        where
-            F: FnMut(Builder, &'a Table) -> Builder,
-        {
-            self.handle_items(key, |b, item| func(b, item.as_table().unwrap()))
-        }
-        fn handle_common(self, fixups: &mut Vec<Fixup>) -> BuilderWithConfig<'a> {
-            self.handle_str_items("headers", |b, item| b.header(add_include(item)))
-                .handle_str_items("raw-lines", |b, item| b.raw_line(item))
-                .handle_str_items("hide-types", |b, item| b.blacklist_type(item))
-                .handle_table_items("fixups", |builder, item| {
-                    fixups.push(Fixup {
-                        pat: item["pat"].as_str().unwrap().into(),
-                        rep: item["rep"].as_str().unwrap().into(),
-                    });
-                    builder
-                })
+struct BuilderWithConfig<'a> {
+    builder: Builder,
+    config: &'a Table,
+    used_keys: HashSet<&'static str>,
+}
+impl<'a> BuilderWithConfig<'a> {
+    fn new(builder: Builder, config: &'a Table) -> Self {
+        BuilderWithConfig {
+            builder,
+            config,
+            used_keys: HashSet::new(),
         }
+    }
 
-        fn get_builder(self) -> Builder {
-            for key in self.config.keys() {
-                if !self.used_keys.contains(key.as_str()) {
-                    panic!(format!("Unknown key: {}", key));
-                }
-            }
-            self.builder
+    fn handle_list<F>(self, key: &'static str, func: F) -> BuilderWithConfig<'a>
+    where
+        F: FnOnce(Builder, slice::Iter<'a, toml::Value>) -> Builder,
+    {
+        let mut builder = self.builder;
+        let config = self.config;
+        let mut used_keys = self.used_keys;
+        if let Some(list) = config.get(key) {
+            used_keys.insert(key);
+            builder = func(builder, list.as_array().unwrap().as_slice().iter());
+        }
+        BuilderWithConfig {
+            builder,
+            config,
+            used_keys,
         }
     }
-
-    fn generate_structs() {
-        let builder = Builder::get_initial_builder()
-            .enable_cxx_namespaces()
-            .with_codegen_config(
-                CodegenConfig::TYPES | CodegenConfig::VARS | CodegenConfig::FUNCTIONS,
-            );
-        let mut fixups = vec![];
-        let builder = BuilderWithConfig::new(builder, CONFIG["structs"].as_table().unwrap())
-            .handle_common(&mut fixups)
-            .handle_str_items("whitelist-functions", |b, item| b.whitelist_function(item))
-            .handle_str_items("bitfield-enums", |b, item| b.bitfield_enum(item))
-            .handle_str_items("rusty-enums", |b, item| b.rustified_enum(item))
-            .handle_str_items("whitelist-vars", |b, item| b.whitelist_var(item))
-            .handle_str_items("whitelist-types", |b, item| b.whitelist_type(item))
-            .handle_str_items("opaque-types", |b, item| b.opaque_type(item))
-            .handle_table_items("cbindgen-types", |b, item| {
-                let gecko = item["gecko"].as_str().unwrap();
-                let servo = item["servo"].as_str().unwrap();
-                b.blacklist_type(format!("mozilla::{}", gecko))
-                    .module_raw_line("root::mozilla", format!("pub use {} as {};", servo, gecko))
-            })
-            .handle_table_items("mapped-generic-types", |builder, item| {
-                let generic = item["generic"].as_bool().unwrap();
-                let gecko = item["gecko"].as_str().unwrap();
-                let servo = item["servo"].as_str().unwrap();
-                let gecko_name = gecko.rsplit("::").next().unwrap();
-                let gecko = gecko
-                    .split("::")
-                    .map(|s| format!("\\s*{}\\s*", s))
-                    .collect::<Vec<_>>()
-                    .join("::");
-
+    fn handle_items<F>(self, key: &'static str, mut func: F) -> BuilderWithConfig<'a>
+    where
+        F: FnMut(Builder, &'a toml::Value) -> Builder,
+    {
+        self.handle_list(key, |b, iter| iter.fold(b, |b, item| func(b, item)))
+    }
+    fn handle_str_items<F>(self, key: &'static str, mut func: F) -> BuilderWithConfig<'a>
+    where
+        F: FnMut(Builder, &'a str) -> Builder,
+    {
+        self.handle_items(key, |b, item| func(b, item.as_str().unwrap()))
+    }
+    fn handle_table_items<F>(self, key: &'static str, mut func: F) -> BuilderWithConfig<'a>
+    where
+        F: FnMut(Builder, &'a Table) -> Builder,
+    {
+        self.handle_items(key, |b, item| func(b, item.as_table().unwrap()))
+    }
+    fn handle_common(self, fixups: &mut Vec<Fixup>) -> BuilderWithConfig<'a> {
+        self.handle_str_items("headers", |b, item| b.header(add_include(item)))
+            .handle_str_items("raw-lines", |b, item| b.raw_line(item))
+            .handle_str_items("hide-types", |b, item| b.blacklist_type(item))
+            .handle_table_items("fixups", |builder, item| {
                 fixups.push(Fixup {
-                    pat: format!("\\broot\\s*::\\s*{}\\b", gecko),
-                    rep: format!("::gecko_bindings::structs::{}", gecko_name),
+                    pat: item["pat"].as_str().unwrap().into(),
+                    rep: item["rep"].as_str().unwrap().into(),
                 });
-                builder.blacklist_type(gecko).raw_line(format!(
-                    "pub type {0}{2} = {1}{2};",
-                    gecko_name,
-                    servo,
-                    if generic { "<T>" } else { "" }
-                ))
+                builder
             })
-            .get_builder();
-        write_binding_file(builder, STRUCTS_FILE, &fixups);
     }
 
-    fn setup_logging() -> bool {
-        struct BuildLogger {
-            file: Option<Mutex<fs::File>>,
-            filter: String,
+    fn get_builder(self) -> Builder {
+        for key in self.config.keys() {
+            if !self.used_keys.contains(key.as_str()) {
+                panic!(format!("Unknown key: {}", key));
+            }
         }
+        self.builder
+    }
+}
 
-        impl log::Log for BuildLogger {
-            fn enabled(&self, meta: &log::Metadata) -> bool {
-                self.file.is_some() && meta.target().contains(&self.filter)
-            }
+fn generate_structs() {
+    let builder = Builder::get_initial_builder()
+        .enable_cxx_namespaces()
+        .with_codegen_config(CodegenConfig::TYPES | CodegenConfig::VARS | CodegenConfig::FUNCTIONS);
+    let mut fixups = vec![];
+    let builder = BuilderWithConfig::new(builder, CONFIG["structs"].as_table().unwrap())
+        .handle_common(&mut fixups)
+        .handle_str_items("whitelist-functions", |b, item| b.whitelist_function(item))
+        .handle_str_items("bitfield-enums", |b, item| b.bitfield_enum(item))
+        .handle_str_items("rusty-enums", |b, item| b.rustified_enum(item))
+        .handle_str_items("whitelist-vars", |b, item| b.whitelist_var(item))
+        .handle_str_items("whitelist-types", |b, item| b.whitelist_type(item))
+        .handle_str_items("opaque-types", |b, item| b.opaque_type(item))
+        .handle_table_items("cbindgen-types", |b, item| {
+            let gecko = item["gecko"].as_str().unwrap();
+            let servo = item["servo"].as_str().unwrap();
+            b.blacklist_type(format!("mozilla::{}", gecko))
+                .module_raw_line("root::mozilla", format!("pub use {} as {};", servo, gecko))
+        })
+        .handle_table_items("mapped-generic-types", |builder, item| {
+            let generic = item["generic"].as_bool().unwrap();
+            let gecko = item["gecko"].as_str().unwrap();
+            let servo = item["servo"].as_str().unwrap();
+            let gecko_name = gecko.rsplit("::").next().unwrap();
+            let gecko = gecko
+                .split("::")
+                .map(|s| format!("\\s*{}\\s*", s))
+                .collect::<Vec<_>>()
+                .join("::");
+
+            fixups.push(Fixup {
+                pat: format!("\\broot\\s*::\\s*{}\\b", gecko),
+                rep: format!("::gecko_bindings::structs::{}", gecko_name),
+            });
+            builder.blacklist_type(gecko).raw_line(format!(
+                "pub type {0}{2} = {1}{2};",
+                gecko_name,
+                servo,
+                if generic { "<T>" } else { "" }
+            ))
+        })
+        .get_builder();
+    write_binding_file(builder, STRUCTS_FILE, &fixups);
+}
 
-            fn log(&self, record: &log::Record) {
-                if !self.enabled(record.metadata()) {
-                    return;
-                }
+fn setup_logging() -> bool {
+    struct BuildLogger {
+        file: Option<Mutex<fs::File>>,
+        filter: String,
+    }
 
-                let mut file = self.file.as_ref().unwrap().lock().unwrap();
-                let _ = writeln!(
-                    file,
-                    "{} - {} - {} @ {}:{}",
-                    record.level(),
-                    record.target(),
-                    record.args(),
-                    record.file().unwrap_or("<unknown>"),
-                    record.line().unwrap_or(0)
-                );
-            }
+    impl log::Log for BuildLogger {
+        fn enabled(&self, meta: &log::Metadata) -> bool {
+            self.file.is_some() && meta.target().contains(&self.filter)
+        }
 
-            fn flush(&self) {
-                if let Some(ref file) = self.file {
-                    file.lock().unwrap().flush().unwrap();
-                }
+        fn log(&self, record: &log::Record) {
+            if !self.enabled(record.metadata()) {
+                return;
             }
-        }
 
-        if let Some(path) = env::var_os("STYLO_BUILD_LOG") {
-            log::set_max_level(log::LevelFilter::Debug);
-            log::set_boxed_logger(Box::new(BuildLogger {
-                file: fs::File::create(path).ok().map(Mutex::new),
-                filter: env::var("STYLO_BUILD_FILTER")
-                    .ok()
-                    .unwrap_or_else(|| "bindgen".to_owned()),
-            }))
-            .expect("Failed to set logger.");
-
-            true
-        } else {
-            false
+            let mut file = self.file.as_ref().unwrap().lock().unwrap();
+            let _ = writeln!(
+                file,
+                "{} - {} - {} @ {}:{}",
+                record.level(),
+                record.target(),
+                record.args(),
+                record.file().unwrap_or("<unknown>"),
+                record.line().unwrap_or(0)
+            );
         }
-    }
 
-    fn generate_atoms() {
-        let script = PathBuf::from(env::var_os("CARGO_MANIFEST_DIR").unwrap())
-            .join("gecko")
-            .join("regen_atoms.py");
-        println!("cargo:rerun-if-changed={}", script.display());
-        let status = Command::new(&*PYTHON)
-            .arg(&script)
-            .arg(DISTDIR_PATH.as_os_str())
-            .arg(OUTDIR_PATH.as_os_str())
-            .status()
-            .unwrap();
-        if !status.success() {
-            exit(1);
+        fn flush(&self) {
+            if let Some(ref file) = self.file {
+                file.lock().unwrap().flush().unwrap();
+            }
         }
     }
 
-    pub fn generate() {
-        setup_logging();
-        generate_structs();
-        generate_atoms();
-
-        for path in ADDED_PATHS.lock().unwrap().iter() {
-            println!("cargo:rerun-if-changed={}", path.to_str().unwrap());
-        }
+    if let Some(path) = env::var_os("STYLO_BUILD_LOG") {
+        log::set_max_level(log::LevelFilter::Debug);
+        log::set_boxed_logger(Box::new(BuildLogger {
+            file: fs::File::create(path).ok().map(Mutex::new),
+            filter: env::var("STYLO_BUILD_FILTER")
+                .ok()
+                .unwrap_or_else(|| "bindgen".to_owned()),
+        }))
+        .expect("Failed to set logger.");
+
+        true
+    } else {
+        false
     }
 }
 
-#[cfg(not(feature = "bindgen"))]
-mod bindings {
-    use super::common::*;
-    use std::path::{Path, PathBuf};
-    use std::{env, fs, io};
-
-    /// Copy contents of one directory into another.
-    /// It currently only does a shallow copy.
-    fn copy_dir<P, Q, F>(from: P, to: Q, callback: F) -> io::Result<()>
-    where
-        P: AsRef<Path>,
-        Q: AsRef<Path>,
-        F: Fn(&Path),
-    {
-        let to = to.as_ref();
-        for entry in from.as_ref().read_dir()? {
-            let entry = entry?;
-            let path = entry.path();
-            callback(&path);
-            fs::copy(&path, to.join(entry.file_name()))?;
-        }
-        Ok(())
-    }
-
-    pub fn generate() {
-        let dir = PathBuf::from(env::var_os("CARGO_MANIFEST_DIR").unwrap()).join("gecko/generated");
-        println!("cargo:rerun-if-changed={}", dir.display());
-        copy_dir(&dir, &*OUTDIR_PATH, |path| {
-            println!("cargo:rerun-if-changed={}", path.display());
-        })
-        .expect("Fail to copy generated files to out dir");
+fn generate_atoms() {
+    let script = PathBuf::from(env::var_os("CARGO_MANIFEST_DIR").unwrap())
+        .join("gecko")
+        .join("regen_atoms.py");
+    println!("cargo:rerun-if-changed={}", script.display());
+    let status = Command::new(&*PYTHON)
+        .arg(&script)
+        .arg(DISTDIR_PATH.as_os_str())
+        .arg(OUTDIR_PATH.as_os_str())
+        .status()
+        .unwrap();
+    if !status.success() {
+        exit(1);
     }
 }
 
 pub fn generate() {
-    use self::common::*;
-    use std::fs;
     println!("cargo:rerun-if-changed=build_gecko.rs");
     fs::create_dir_all(&*OUTDIR_PATH).unwrap();
-    bindings::generate();
+    setup_logging();
+    generate_structs();
+    generate_atoms();
+
+    for path in ADDED_PATHS.lock().unwrap().iter() {
+        println!("cargo:rerun-if-changed={}", path.to_str().unwrap());
+    }
 }