gen: Allow specifying raw lines before the content starts

It's useful to add `use` or `include!` lines.

2 files changed, 26 insertions, 2 deletions

diff --git a/src/bin/bindgen.rs b/src/bin/bindgen.rs
index 67ddc8a8..42c0cb40 100644
--- a/src/bin/bindgen.rs
+++ b/src/bin/bindgen.rs
@@ -139,6 +139,13 @@ fn parse_args(args: &[String]) -> ParseResult {
                     options.rename_types = false;
                     ix += 1;
                 }
+                "-raw-line" => {
+                    if ix + 1 >= args_len {
+                        return ParseResult::ParseErr("Missing raw-line argument".to_string());
+                    }
+                    options.raw_lines.push(args[ix + 1].clone());
+                    ix += 2;
+                }
                 _ => {
                     options.clang_args.push(args[ix].clone());
                     ix += 1;
diff --git a/src/lib.rs b/src/lib.rs
index f8a392c3..c5737035 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -61,6 +61,11 @@ impl<'a> Builder<'a> {
         self
     }
 
+    pub fn raw_line<T: Into<String>>(&mut self, arg: T) -> &mut Self {
+        self.options.raw_lines.push(arg.into());
+        self
+    }
+
     pub fn clang_arg<T: Into<String>>(&mut self, arg: T) -> &mut Self {
         self.options.clang_args.push(arg.into());
         self
@@ -142,6 +147,7 @@ pub struct BindgenOptions {
     pub rename_types: bool,
     pub derive_debug: bool,
     pub override_enum_ty: String,
+    pub raw_lines: Vec<String>,
     pub clang_args: Vec<String>,
 }
 
@@ -162,6 +168,7 @@ impl Default for BindgenOptions {
             derive_debug: true,
             enable_cxx_namespaces: false,
             override_enum_ty: "".to_string(),
+            raw_lines: vec![],
             clang_args: Vec::new()
         }
     }
@@ -181,7 +188,8 @@ pub trait Logger {
 
 #[derive(Debug, Clone)]
 pub struct Bindings {
-    module: ast::Mod
+    module: ast::Mod,
+    raw_lines: Vec<String>,
 }
 
 impl Bindings {
@@ -203,7 +211,8 @@ impl Bindings {
         };
 
         Ok(Bindings {
-            module: module
+            module: module,
+            raw_lines: options.raw_lines.clone(),
         })
     }
 
@@ -229,6 +238,14 @@ impl Bindings {
     #[cfg_attr(feature = "clippy", allow(needless_lifetimes))]
     pub fn write<'a>(&self, mut writer: Box<Write + 'a>) -> io::Result<()> {
         try!(writer.write("/* automatically generated by rust-bindgen */\n\n".as_bytes()));
+
+        for line in self.raw_lines.iter() {
+            try!(writer.write(line.as_bytes()));
+        }
+        if !self.raw_lines.is_empty() {
+            try!(writer.write("\n\n".as_bytes()));
+        }
+
         let mut ps = pprust::rust_printer(writer);
         try!(ps.print_mod(&self.module, &[]));
         try!(ps.print_remaining_comments());