Added a separate bindgen building crate and pre-generated bindings

implot-sys-bindgen/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "implot-sys-bindgen"
+version = "0.1.0"
+authors = ["Sandro Merkli"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+bindgen = "0.53.1"
+imgui-sys = { git = "https://github.com/Gekkio/imgui-rs/", branch = "master" }
+imgui = { git = "https://github.com/Gekkio/imgui-rs/", branch = "master" }

implot-sys-bindgen/build.rs

@@ -0,0 +1,16 @@
+use std::env;
+use std::io::Write;
+use std::path::PathBuf;
+
+fn main() {
+    // We just forward the DEP_IMGUI_THIRD_PARTY variable here because the
+    // main function outside the build script does not actually see it
+    let cimgui_include_path =
+        env::var_os("DEP_IMGUI_THIRD_PARTY").expect("DEP_IMGUI_THIRD_PARTY not defined");
+    println!(
+        "cargo:rustc-env=DEP_IMGUI_THIRD_PARTY={}",
+        cimgui_include_path
+            .to_str()
+            .expect("Could not turn cimgui include path to string")
+    );
+}

implot-sys-bindgen/src/main.rs

@@ -0,0 +1,44 @@
+use bindgen::{Builder, CargoCallbacks};
+use std::{env, path::PathBuf};
+
+// All this crate does is run bindgen on cimplot and store the result
+// in the src folder of the implot-sys crate. We add those bindings
+// to git so people don't have to install clang just to use implot-rs.
+
+fn main() {
+    let cwd = env::current_dir().expect("Could not read current directory");
+    let sys_crate_path = cwd
+        .join("..")
+        .join("implot-sys")
+        .canonicalize()
+        .expect("Could not find sys crate directory");
+
+    let cimgui_include_path = PathBuf::from(
+        env::var_os("DEP_IMGUI_THIRD_PARTY").expect("DEP_IMGUI_THIRD_PARTY not defined"),
+    );
+
+    let bindings = Builder::default()
+        .header(
+            cimgui_include_path
+                .join("cimgui.h")
+                .to_str()
+                .expect("Could not convert cimgui.h path to string"),
+        )
+        .header(
+            sys_crate_path
+                .join("third-party")
+                .join("cimplot")
+                .join("cimplot.h")
+                .to_str()
+                .expect("Could not turn cimplot.h path into string"),
+        )
+        .parse_callbacks(Box::new(CargoCallbacks))
+        .clang_arg("-DCIMGUI_DEFINE_ENUMS_AND_STRUCTS=1")
+        .generate()
+        .expect("Unable to generate bindings");
+
+    let out_path = sys_crate_path.join("src");
+    bindings
+        .write_to_file(&out_path.join("bindings.rs"))
+        .expect("Couldn't write bindings!");
+}

implot-sys/Cargo.toml

@@ -15,4 +15,3 @@ imgui = { git = "https://github.com/Gekkio/imgui-rs/", branch = "master" }
 
 [build-dependencies]
 cc = "1.0"
-bindgen = "0.53.1"

implot-sys/build.rs

@@ -5,8 +5,6 @@
 // for now, but expected to diverge from that over time.
 use std::{env, fs, io, path::Path};
 
-use bindgen;
-
 const CPP_FILES: [&str; 2] = [
     "third-party/cimplot/cimplot.cpp",
     "third-party/cimplot/implot/implot.cpp",
@@ -54,24 +52,6 @@ fn main() -> io::Result<()> {
         assert_file_exists(path)?;
         build.file(path);
     }
-
     build.compile("cimplot");
-
-    // --- Create bindgen bindings
-    // TODO(4bb4) move this out to separate shell script (see #1) so users don't have
-    // to have clang installed to build this crate.
-    let bindings = bindgen::Builder::default()
-        .header(&(cimgui_include_path.into_string().unwrap() + "/cimgui.h"))
-        .header("third-party/cimplot/cimplot.h")
-        .parse_callbacks(Box::new(bindgen::CargoCallbacks))
-        .clang_arg("-DCIMGUI_DEFINE_ENUMS_AND_STRUCTS=1")
-        .generate()
-        .expect("Unable to generate bindings");
-
-    let out_path = std::path::PathBuf::from(env::var("OUT_DIR").unwrap());
-    bindings
-        .write_to_file(out_path.join("bindings.rs"))
-        .expect("Couldn't write bindings!");
-
     Ok(())
 }

implot-sys/src/lib.rs

@@ -2,6 +2,4 @@
 #![allow(non_camel_case_types)]
 #![allow(non_snake_case)]
 
-// TODO(4bb4) change this to include the bindings we hand-generate
+include!("bindings.rs");
-// once that is happening
-include!(concat!(env!("OUT_DIR"), "/bindings.rs"));