1 files changed, 102 insertions, 0 deletions
diff --git a/build/RunCbindgen.py b/build/RunCbindgen.py
new file mode 100644
index 0000000000..e166556f68
--- /dev/null
+++ b/build/RunCbindgen.py
@@ -0,0 +1,102 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import os
+import subprocess
+
+import buildconfig
+import mozpack.path as mozpath
+import six
+import toml
+
+
+# Try to read the package name or otherwise assume same name as the crate path.
+def _get_crate_name(crate_path):
+    try:
+        with open(mozpath.join(crate_path, "Cargo.toml"), encoding="utf-8") as f:
+            return toml.load(f)["package"]["name"]
+    except Exception:
+        return mozpath.basename(crate_path)
+
+
+CARGO_LOCK = mozpath.join(buildconfig.topsrcdir, "Cargo.lock")
+CARGO_TOML = mozpath.join(buildconfig.topsrcdir, "Cargo.toml")
+
+
+def _run_process(args):
+    env = os.environ.copy()
+    env["CARGO"] = str(buildconfig.substs["CARGO"])
+    env["RUSTC"] = str(buildconfig.substs["RUSTC"])
+
+    p = subprocess.Popen(args, env=env, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+
+    stdout, stderr = p.communicate()
+    stdout = six.ensure_text(stdout)
+    stderr = six.ensure_text(stderr)
+    if p.returncode != 0:
+        print(stdout)
+        print(stderr)
+    return (stdout, p.returncode)
+
+
+def generate_metadata(output, cargo_config):
+    args = [
+        buildconfig.substs["CARGO"],
+        "metadata",
+        "--all-features",
+        "--format-version",
+        "1",
+        "--manifest-path",
+        CARGO_TOML,
+    ]
+
+    # The Spidermonkey library can be built from a package tarball outside the
+    # tree, so we want to let Cargo create lock files in this case. When built
+    # within a tree, the Rust dependencies have been vendored in so Cargo won't
+    # touch the lock file.
+    if not buildconfig.substs.get("JS_STANDALONE"):
+        args.append("--frozen")
+
+    stdout, returncode = _run_process(args)
+
+    if returncode != 0:
+        return returncode
+
+    output.write(stdout)
+
+    # This is not quite accurate, but cbindgen only cares about a subset of the
+    # data which, when changed, causes these files to change.
+    return set([CARGO_LOCK, CARGO_TOML])
+
+
+def generate(output, metadata_path, cbindgen_crate_path, *in_tree_dependencies):
+    stdout, returncode = _run_process(
+        [
+            buildconfig.substs["CBINDGEN"],
+            buildconfig.topsrcdir,
+            "--lockfile",
+            CARGO_LOCK,
+            "--crate",
+            _get_crate_name(cbindgen_crate_path),
+            "--metadata",
+            metadata_path,
+            "--cpp-compat",
+        ]
+    )
+
+    if returncode != 0:
+        return returncode
+
+    output.write(stdout)
+
+    deps = set()
+    deps.add(CARGO_LOCK)
+    deps.add(mozpath.join(cbindgen_crate_path, "cbindgen.toml"))
+    for directory in in_tree_dependencies + (cbindgen_crate_path,):
+        for path, dirs, files in os.walk(directory):
+            for file in files:
+                if os.path.splitext(file)[1] == ".rs":
+                    deps.add(mozpath.join(path, file))
+
+    return deps