Use absolute paths for unsaved files passed to clang and prepend -include directives to them.

Fixes #1771
Closes #1857

Author: Andrey Pushkar

src/lib.rs

@@ -596,8 +596,16 @@ impl Builder {
     ///
     /// The file `name` will be added to the clang arguments.
     pub fn header_contents(mut self, name: &str, contents: &str) -> Builder {
+        // Apparently clang relies on having virtual FS correspondent to
+        // the real one, so we need absolute paths here
+        let absolute_path = env::current_dir()
+            .expect("Cannot retrieve current directory")
+            .join(name)
+            .to_str()
+            .expect("Cannot convert current directory name to string")
+            .to_owned();
         self.input_header_contents
-            .push((name.into(), contents.into()));
+            .push((absolute_path, contents.into()));
         self
     }
 
@@ -2154,7 +2162,10 @@ impl Bindings {
             }
         }
 
-        for f in options.input_unsaved_files.iter() {
+        for (idx, f) in options.input_unsaved_files.iter().enumerate() {
+            if idx != 0 || options.input_header.is_some() {
+                options.clang_args.push("-include".to_owned());
+            }
             options.clang_args.push(f.name.to_str().unwrap().to_owned())
         }
 

tests/expectations/tests/test_mixed_header_and_header_contents.rs

@@ -0,0 +1,111 @@
+extern "C" {
+    pub static mut foo: ::std::option::Option<
+        unsafe extern "C" fn(
+            x: ::std::os::raw::c_int,
+            y: ::std::os::raw::c_int,
+        ) -> ::std::os::raw::c_int,
+    >;
+}
+extern "C" {
+    pub fn bar(a: *const ::std::os::raw::c_char) -> ::std::os::raw::c_int;
+}
+extern "C" {
+    pub fn bar2(b: *const ::std::os::raw::c_char) -> f32;
+}
+pub type Char = ::std::os::raw::c_char;
+pub type SChar = ::std::os::raw::c_schar;
+pub type UChar = ::std::os::raw::c_uchar;
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct Test {
+    pub ch: ::std::os::raw::c_char,
+    pub u: ::std::os::raw::c_uchar,
+    pub d: ::std::os::raw::c_schar,
+    pub cch: ::std::os::raw::c_char,
+    pub cu: ::std::os::raw::c_uchar,
+    pub cd: ::std::os::raw::c_schar,
+    pub Cch: Char,
+    pub Cu: UChar,
+    pub Cd: SChar,
+    pub Ccch: Char,
+    pub Ccu: UChar,
+    pub Ccd: SChar,
+}
+#[test]
+fn bindgen_test_layout_Test() {
+    assert_eq!(
+        ::std::mem::size_of::<Test>(),
+        12usize,
+        concat!("Size of: ", stringify!(Test))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<Test>(),
+        1usize,
+        concat!("Alignment of ", stringify!(Test))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<Test>())).ch as *const _ as usize },
+        0usize,
+        concat!("Offset of field: ", stringify!(Test), "::", stringify!(ch))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<Test>())).u as *const _ as usize },
+        1usize,
+        concat!("Offset of field: ", stringify!(Test), "::", stringify!(u))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<Test>())).d as *const _ as usize },
+        2usize,
+        concat!("Offset of field: ", stringify!(Test), "::", stringify!(d))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<Test>())).cch as *const _ as usize },
+        3usize,
+        concat!("Offset of field: ", stringify!(Test), "::", stringify!(cch))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<Test>())).cu as *const _ as usize },
+        4usize,
+        concat!("Offset of field: ", stringify!(Test), "::", stringify!(cu))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<Test>())).cd as *const _ as usize },
+        5usize,
+        concat!("Offset of field: ", stringify!(Test), "::", stringify!(cd))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<Test>())).Cch as *const _ as usize },
+        6usize,
+        concat!("Offset of field: ", stringify!(Test), "::", stringify!(Cch))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<Test>())).Cu as *const _ as usize },
+        7usize,
+        concat!("Offset of field: ", stringify!(Test), "::", stringify!(Cu))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<Test>())).Cd as *const _ as usize },
+        8usize,
+        concat!("Offset of field: ", stringify!(Test), "::", stringify!(Cd))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<Test>())).Ccch as *const _ as usize },
+        9usize,
+        concat!(
+            "Offset of field: ",
+            stringify!(Test),
+            "::",
+            stringify!(Ccch)
+        )
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<Test>())).Ccu as *const _ as usize },
+        10usize,
+        concat!("Offset of field: ", stringify!(Test), "::", stringify!(Ccu))
+    );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<Test>())).Ccd as *const _ as usize },
+        11usize,
+        concat!("Offset of field: ", stringify!(Test), "::", stringify!(Ccd))
+    );
+}

tests/tests.rs

@@ -473,6 +473,60 @@ fn test_multiple_header_calls_in_builder() {
     }
 }
 
+#[test]
+fn test_multiple_header_contents() {
+    let actual = builder()
+        .header_contents("test.h", "int foo(const char* a);")
+        .header_contents("test2.h", "float foo2(const char* b);")
+        .clang_arg("--target=x86_64-unknown-linux")
+        .generate()
+        .unwrap()
+        .to_string();
+
+    let (actual, stderr) = rustfmt(actual);
+    println!("{}", stderr);
+
+    let (expected, _) = rustfmt(
+        "extern \"C\" {
+    pub fn foo2(b: *const ::std::os::raw::c_char) -> f32;
+}
+extern \"C\" {
+    pub fn foo(a: *const ::std::os::raw::c_char) -> ::std::os::raw::c_int;
+}
+"
+        .to_string(),
+    );
+
+    assert_eq!(expected, actual);
+}
+
+#[test]
+fn test_mixed_header_and_header_contents() {
+    let actual = builder()
+        .header(concat!(
+            env!("CARGO_MANIFEST_DIR"),
+            "/tests/headers/func_ptr.h"
+        ))
+        .header(concat!(env!("CARGO_MANIFEST_DIR"), "/tests/headers/char.h"))
+        .header_contents("test.h", "int bar(const char* a);")
+        .header_contents("test2.h", "float bar2(const char* b);")
+        .clang_arg("--target=x86_64-unknown-linux")
+        .generate()
+        .unwrap()
+        .to_string();
+
+    let (actual, stderr) = rustfmt(actual);
+    println!("{}", stderr);
+
+    let expected = include_str!(concat!(
+        env!("CARGO_MANIFEST_DIR"),
+        "/tests/expectations/tests/test_mixed_header_and_header_contents.rs"
+    ));
+    let (expected, _) = rustfmt(expected.to_string());
+
+    assert_eq!(expected, actual);
+}
+
 #[test]
 // Doesn't support executing sh file on Windows.
 // We may want to implement it in Rust so that we support all systems.