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// Copyright 2015 Brendan Zabarauskas and the gl-rs developers
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
use registry::Registry;
use std::io;
#[allow(missing_copy_implementations)]
pub struct StructGenerator;
impl super::Generator for StructGenerator {
fn write<W>(&self, registry: &Registry, dest: &mut W) -> io::Result<()>
where
W: io::Write,
{
try!(write_header(dest));
try!(write_type_aliases(registry, dest));
try!(write_enums(registry, dest));
try!(write_fnptr_struct_def(dest));
try!(write_panicking_fns(registry, dest));
try!(write_struct(registry, dest));
try!(write_impl(registry, dest));
Ok(())
}
}
/// Creates a `__gl_imports` module which contains all the external symbols that we need for the
/// bindings.
fn write_header<W>(dest: &mut W) -> io::Result<()>
where
W: io::Write,
{
writeln!(
dest,
r#"
mod __gl_imports {{
pub use std::mem;
pub use std::marker::Send;
pub use std::os::raw;
}}
"#
)
}
/// Creates a `types` module which contains all the type aliases.
///
/// See also `generators::gen_types`.
fn write_type_aliases<W>(registry: &Registry, dest: &mut W) -> io::Result<()>
where
W: io::Write,
{
try!(writeln!(
dest,
r#"
pub mod types {{
#![allow(non_camel_case_types, non_snake_case, dead_code, missing_copy_implementations)]
"#
));
try!(super::gen_types(registry.api, dest));
writeln!(dest, "}}")
}
/// Creates all the `<enum>` elements at the root of the bindings.
fn write_enums<W>(registry: &Registry, dest: &mut W) -> io::Result<()>
where
W: io::Write,
{
for enm in ®istry.enums {
try!(super::gen_enum_item(enm, "types::", dest));
}
Ok(())
}
/// Creates a `FnPtr` structure which contains the store for a single binding.
fn write_fnptr_struct_def<W>(dest: &mut W) -> io::Result<()>
where
W: io::Write,
{
writeln!(
dest,
"
#[allow(dead_code, missing_copy_implementations)]
#[derive(Clone)]
pub struct FnPtr {{
/// The function pointer that will be used when calling the function.
f: *const __gl_imports::raw::c_void,
/// True if the pointer points to a real function, false if points to a `panic!` fn.
is_loaded: bool,
}}
impl FnPtr {{
/// Creates a `FnPtr` from a load attempt.
fn new(ptr: *const __gl_imports::raw::c_void) -> FnPtr {{
if ptr.is_null() {{
FnPtr {{
f: missing_fn_panic as *const __gl_imports::raw::c_void,
is_loaded: false
}}
}} else {{
FnPtr {{ f: ptr, is_loaded: true }}
}}
}}
/// Returns `true` if the function has been successfully loaded.
///
/// If it returns `false`, calling the corresponding function will fail.
#[inline]
#[allow(dead_code)]
pub fn is_loaded(&self) -> bool {{
self.is_loaded
}}
}}
"
)
}
/// Creates a `panicking` module which contains one function per GL command.
///
/// These functions are the mocks that are called if the real function could not be loaded.
fn write_panicking_fns<W>(registry: &Registry, dest: &mut W) -> io::Result<()>
where
W: io::Write,
{
writeln!(
dest,
"#[inline(never)]
fn missing_fn_panic() -> ! {{
panic!(\"{api} function was not loaded\")
}}",
api = registry.api
)
}
/// Creates a structure which stores all the `FnPtr` of the bindings.
///
/// The name of the struct corresponds to the namespace.
fn write_struct<W>(registry: &Registry, dest: &mut W) -> io::Result<()>
where
W: io::Write,
{
try!(writeln!(
dest,
"
#[allow(non_camel_case_types, non_snake_case, dead_code)]
#[derive(Clone)]
pub struct {api} {{",
api = super::gen_struct_name(registry.api)
));
for cmd in ®istry.cmds {
if let Some(v) = registry.aliases.get(&cmd.proto.ident) {
try!(writeln!(dest, "/// Fallbacks: {}", v.join(", ")));
}
try!(writeln!(dest, "pub {name}: FnPtr,", name = cmd.proto.ident));
}
try!(writeln!(dest, "_priv: ()"));
writeln!(dest, "}}")
}
/// Creates the `impl` of the structure created by `write_struct`.
fn write_impl<W>(registry: &Registry, dest: &mut W) -> io::Result<()>
where
W: io::Write,
{
try!(writeln!(dest,
"impl {api} {{
/// Load each OpenGL symbol using a custom load function. This allows for the
/// use of functions like `glfwGetProcAddress` or `SDL_GL_GetProcAddress`.
///
/// ~~~ignore
/// let gl = Gl::load_with(|s| glfw.get_proc_address(s));
/// ~~~
#[allow(dead_code, unused_variables)]
pub fn load_with<F>(mut loadfn: F) -> {api} where F: FnMut(&'static str) -> *const __gl_imports::raw::c_void {{
#[inline(never)]
fn do_metaloadfn(loadfn: &mut dyn FnMut(&'static str) -> *const __gl_imports::raw::c_void,
symbol: &'static str,
symbols: &[&'static str])
-> *const __gl_imports::raw::c_void {{
let mut ptr = loadfn(symbol);
if ptr.is_null() {{
for &sym in symbols {{
ptr = loadfn(sym);
if !ptr.is_null() {{ break; }}
}}
}}
ptr
}}
let mut metaloadfn = |symbol: &'static str, symbols: &[&'static str]| {{
do_metaloadfn(&mut loadfn, symbol, symbols)
}};
{api} {{",
api = super::gen_struct_name(registry.api)));
for cmd in ®istry.cmds {
try!(writeln!(
dest,
"{name}: FnPtr::new(metaloadfn(\"{symbol}\", &[{fallbacks}])),",
name = cmd.proto.ident,
symbol = super::gen_symbol_name(registry.api, &cmd.proto.ident),
fallbacks = match registry.aliases.get(&cmd.proto.ident) {
Some(fbs) => fbs
.iter()
.map(|name| format!("\"{}\"", super::gen_symbol_name(registry.api, &name)))
.collect::<Vec<_>>()
.join(", "),
None => format!(""),
},
))
}
try!(writeln!(dest, "_priv: ()"));
try!(writeln!(
dest,
"}}
}}"
));
for cmd in ®istry.cmds {
try!(writeln!(dest,
"#[allow(non_snake_case, unused_variables, dead_code)]
#[inline] pub unsafe fn {name}(&self, {params}) -> {return_suffix} {{ \
__gl_imports::mem::transmute::<_, extern \"system\" fn({typed_params}) -> {return_suffix}>\
(self.{name}.f)({idents}) \
}}",
name = cmd.proto.ident,
params = super::gen_parameters(cmd, true, true).join(", "),
typed_params = super::gen_parameters(cmd, false, true).join(", "),
return_suffix = cmd.proto.ty,
idents = super::gen_parameters(cmd, true, false).join(", "),
))
}
writeln!(
dest,
"}}
unsafe impl __gl_imports::Send for {api} {{}}",
api = super::gen_struct_name(registry.api)
)
}