Don't mangle using the parse callbacks for whitelisting / blacklisting / etc.

[emilio]

No description provided.

[jethrogb]

Cool, looks good, except for #1221 (comment)

Mini-repro:

# Cargo.toml
[package]
name = "bgtest"
version = "0.1.0"

[dependencies]
bindgen = { git = "https://github.com/emilio/rust-bindgen/", branch = "whitelist-name" }

// src/main.rs
extern crate bindgen;

#[derive(Debug)]
struct ParseCallbacks {}

impl bindgen::callbacks::ParseCallbacks for ParseCallbacks {
    fn item_name(&self, original_item_name: &str) -> Option<String> {
        if original_item_name.starts_with("prefix_") {
            Some(original_item_name.trim_start_matches("prefix_").to_string())
        } else {
            None
        }
    }
}


fn main() {
    let bindings = bindgen::builder()
        .header_contents("test.h", "int prefix_testfn();")
        .parse_callbacks(Box::new(ParseCallbacks{}))
        .whitelist_function("(?i)prefix_.*")
        .trust_clang_mangling(false)
        .generate()
        .expect("bindgen error");

    bindings.write(Box::new(std::io::stdout())).unwrap();
}

Output:

/* automatically generated by rust-bindgen */

extern "C" {
    #[link_name = "\u{1}prefix_testfn"]
    pub fn testfn() -> ::std::os::raw::c_int;
}

[emilio]

Added a test for this.