Extract protoc action into .bzl for cc.
This is needed to support python bazel build.
diff --git a/protobuf.bzl b/protobuf.bzl
new file mode 100644
index 0000000..63ef95f
--- /dev/null
+++ b/protobuf.bzl
@@ -0,0 +1,107 @@
+# -*- mode: python; -*- PYTHON-PREPROCESSING-REQUIRED
+
+
+def _gen_dir(ctx):
+ if not ctx.attr.prefix:
+ return ctx.label.package
+ if not ctx.label.package:
+ return ctx.attr.prefix
+ return ctx.label.package + '/' + ctx.attr.prefix
+
+def CcOuts(srcs):
+ return [s[:-len(".proto")] + ".pb.h" for s in srcs] + \
+ [s[:-len(".proto")] + ".pb.cc" for s in srcs]
+
+def PyOuts(srcs):
+ return [s[:-len(".proto")] + "_pb2.py" for s in srcs]
+
+def _proto_srcs_impl(ctx):
+ """General implementation for calculating proto srcs"""
+ srcs = ctx.files.srcs
+ deps = []
+ deps += ctx.files.srcs
+ gen_dir = _gen_dir(ctx)
+ import_flags = ["-I" + gen_dir]
+ for dep in ctx.attr.deps:
+ import_flags += dep.proto.import_flags
+ deps += dep.proto.deps
+
+ args = []
+ if ctx.attr.gen_cc:
+ args += ["--cpp_out=" + ctx.var["GENDIR"] + "/" + gen_dir]
+ if ctx.attr.gen_py:
+ args += ["--python_out=" + ctx.var["GENDIR"] + "/" + gen_dir]
+
+ if args:
+ ctx.action(
+ inputs= srcs + deps,
+ outputs=ctx.outputs.outs,
+ arguments= args + import_flags + [s.path for s in srcs],
+ executable=ctx.executable.protoc
+ )
+
+ return struct(
+ proto=struct(
+ srcs = srcs,
+ import_flags = import_flags,
+ deps = deps,
+ ),
+ )
+
+_proto_srcs = rule(
+ implementation = _proto_srcs_impl,
+ output_to_genfiles = True,
+ attrs = {
+ "srcs": attr.label_list(allow_files=True),
+ "deps": attr.label_list(providers=["proto"]),
+ "prefix": attr.string(),
+ "protoc": attr.label(executable=True, single_file=True, mandatory=True),
+ "gen_cc": attr.bool(),
+ "gen_py": attr.bool(),
+ "outs": attr.output_list()
+ }
+)
+
+def cc_proto_library(
+ name,
+ srcs=[],
+ protoc=":protoc",
+ internal_bootstrap_hack=False,
+ prefix="",
+ proto_deps=[],
+ deps=[],
+ **kargs):
+
+ if internal_bootstrap_hack:
+ # For pre-checked-in generated files, we add the internal_bootstrap_hack
+ # which will skip the codegen action.
+ _proto_srcs(
+ name = name + "_genproto",
+ srcs = srcs,
+ deps = [s + "_genproto" for s in proto_deps],
+ prefix = prefix,
+ protoc = protoc,
+ )
+ # An empty cc_library to make rule dependency consistent.
+ native.cc_library(
+ name = name,
+ **kargs)
+ return
+
+ outs = CcOuts(srcs)
+ _proto_srcs(
+ name = name + "_genproto",
+ srcs = srcs,
+ deps = [s + "_genproto" for s in proto_deps],
+ prefix = prefix,
+ protoc = protoc,
+ gen_cc = 1,
+ outs = outs,
+ )
+
+ native.cc_library(
+ name = name,
+ srcs = outs,
+ deps = deps + proto_deps,
+ includes = [prefix],
+ **kargs)