From 90b8139c6ed741a30e394599e2430b246030cca9 Mon Sep 17 00:00:00 2001
From: Erin Swenson-Healey <l@s3r.me>
Date: Tue, 24 Jul 2018 09:39:29 -0700
Subject: [PATCH] Automatically generate C header from Rust API (#97)

* generate C header file on build using cbindgen

* add newlines
---
 .gitignore    |  1 +
 Cargo.toml    |  4 +++-
 build.rs      | 18 ++++++++++++++++++
 cbindgen.toml |  3 +++
 4 files changed, 25 insertions(+), 1 deletion(-)
 create mode 100644 build.rs
 create mode 100644 cbindgen.toml

diff --git a/.gitignore b/.gitignore
index d61c9287..5e337146 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 **/*.rs.bk
 Cargo.lock
 .criterion
+**/libproofs.h
diff --git a/Cargo.toml b/Cargo.toml
index 8973d3a0..3bb8f66a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -40,6 +40,8 @@ criterion = "0.2.3"
 tempfile = "3"
 proptest = "0.7"
 
+[build-dependencies]
+cbindgen = "0.6.0"
 
 [[bench]]
 name = "pedersen"
@@ -47,4 +49,4 @@ harness = false
 
 [[bench]]
 name = "drgraph"
-harness = false
\ No newline at end of file
+harness = false
diff --git a/build.rs b/build.rs
new file mode 100644
index 00000000..bfbb1832
--- /dev/null
+++ b/build.rs
@@ -0,0 +1,18 @@
+extern crate cbindgen;
+
+const VERSION: &'static str = env!("CARGO_PKG_VERSION");
+
+fn main() {
+    let crate_dir = std::env::var("CARGO_MANIFEST_DIR").unwrap();
+
+    let cfg = cbindgen::Config::from_root_or_default(std::path::Path::new(&crate_dir));
+
+    cbindgen::Builder::new()
+        .with_config(cfg)
+        .with_crate(crate_dir)
+        .with_header(format!("/* libproofs Header Version {} */", VERSION))
+        .with_language(cbindgen::Language::C)
+        .generate()
+        .expect("Unable to generate bindings")
+        .write_to_file("libproofs.h");
+}
diff --git a/cbindgen.toml b/cbindgen.toml
new file mode 100644
index 00000000..42026e67
--- /dev/null
+++ b/cbindgen.toml
@@ -0,0 +1,3 @@
+[export]
+# A list of symbols to not include in the generated bindings
+exclude = ["MerkleTree"]