shaka-packager/packager/third_party/protobuf/proto_library.gni

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# Copyright 2014 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
# Compile a protocol buffer.
#
# Protobuf parameters:
#
# proto_out_dir (optional)
# Specifies the path suffix that output files are generated under. This
# path will be appended to the root_gen_dir.
#
# Targets that depend on the proto target will be able to include the
# resulting proto headers with an include like:
# #include "dir/for/my_proto_lib/foo.pb.h"
# If undefined, this defaults to matching the input directory for each
# .proto file (you should almost always use the default mode).
#
# generate_python (optional, default true)
# Generate Python protobuf stubs.
#
# generate_cc (optional, default true)
# Generate C++ protobuf stubs.
#
# cc_generator_options (optional)
# List of extra flags passed to the protocol compiler. If you need to
# add an EXPORT macro to a protobuf's C++ header, set the
# 'cc_generator_options' variable with the value:
# 'dllexport_decl=FOO_EXPORT:' (note trailing colon).
#
# It is likely you also need to #include a file for the above EXPORT
# macro to work (see cc_include) and set
# component_build_force_source_set = true.
#
# generator_plugin (optional)
# Name of plugin executable which generates custom cc stubs.
# Plugin itself should be dependency of the invoker.
#
# generator_plugin_suffix (required if generator_plugin set)
# Suffix (before extension) for generated .cc and .h files.
#
# generator_plugin_options (optional)
# Extra flags passed to the plugin. See cc_generator_options.
#
# cc_include (optional)
# String listing an extra include that should be passed.
# Example: cc_include = "foo/bar.h"
#
# deps (optional)
# Additional dependencies.
#
# Parameters for compiling the generated code:
#
# component_build_force_source_set (Default=false)
# When set true the generated code will be compiled as a source set in
# the component build. This does not affect static builds. If you are
# exporting symbols from a component, this is required to prevent those
# symbols from being stripped. If you're not using dllexports in
# cc_generator_options, it's usually best to leave this false.
#
# defines (optional)
# Defines to supply to the source set that compiles the generated source
# code.
#
# extra_configs (optional)
# A list of config labels that will be appended to the configs applying
# to the source set.
#
# Example
# proto_library("mylib") {
# sources = [
# "foo.proto",
# ]
# }
template("proto_library") {
assert(defined(invoker.sources), "Need sources for proto_library")
# Don't apply OS-specific sources filtering to the assignments later on.
# Platform files should have gotten filtered out in the sources assignment
# when this template was invoked. If they weren't, it was on purpose and
# this template shouldn't re-apply the filter.
set_sources_assignment_filter([])
action_name = "${target_name}_gen"
source_set_name = target_name
action_foreach(action_name) {
visibility = [ ":$source_set_name" ]
script = "//tools/protoc_wrapper/protoc_wrapper.py"
sources = invoker.sources
# Compute the output directory, both relative to the source root (for
# declaring "outputs") and relative to the build dir (for passing to the
# script).
if (defined(invoker.proto_out_dir)) {
proto_out_dir = invoker.proto_out_dir
} else {
proto_out_dir = "{{source_root_relative_dir}}"
}
out_dir = "$root_gen_dir/" + proto_out_dir
rel_out_dir = rebase_path(out_dir, root_build_dir)
outputs = []
args = []
if (defined(invoker.cc_include)) {
args += [
"--include",
invoker.cc_include,
"--protobuf",
"$rel_out_dir/{{source_name_part}}.pb.h",
]
}
args += [
"--proto-in-dir",
"{{source_dir}}",
"--proto-in-file",
"{{source_file_part}}",
# TODO(brettw) support system protobuf compiler.
"--use-system-protobuf=0",
]
protoc_label = "//third_party/protobuf:protoc($host_toolchain)"
args += [
"--",
# Prepend with "./" so this will never pick up the system one (normally
# when not cross-compiling, protoc's output directory will be the same
# as the build dir, so the relative location will be empty).
"./" +
rebase_path(get_label_info(protoc_label, "root_out_dir") + "/protoc",
root_build_dir),
]
if (!defined(invoker.generate_python) || invoker.generate_python) {
py_out_dir = "$root_out_dir/pyproto/" + proto_out_dir
rel_py_out_dir = rebase_path(py_out_dir, root_build_dir)
outputs += [ "$py_out_dir/{{source_name_part}}_pb2.py" ]
args += [
"--python_out",
rel_py_out_dir,
]
}
if (!defined(invoker.generate_cc) || invoker.generate_cc) {
# If passed cc_generator_options should end in a colon, which will
# separate it from the directory when we concatenate them. The proto
# compiler understands this syntax.
if (defined(invoker.cc_generator_options)) {
cc_generator_options = invoker.cc_generator_options
} else {
cc_generator_options = ""
}
outputs += [
"$out_dir/{{source_name_part}}.pb.cc",
"$out_dir/{{source_name_part}}.pb.h",
]
args += [
"--cpp_out",
"$cc_generator_options$rel_out_dir", # Separated by colon.
]
}
if (defined(invoker.generator_plugin)) {
generator_plugin = invoker.generator_plugin
generator_plugin_suffix = invoker.generator_plugin_suffix
if (defined(invoker.generator_plugin_options)) {
generator_plugin_options = invoker.generator_plugin_options
} else {
generator_plugin_options = ""
}
outputs += [
"$out_dir/{{source_name_part}}$generator_plugin_suffix.cc",
"$out_dir/{{source_name_part}}$generator_plugin_suffix.h",
]
args += [
"--plugin",
"protoc-gen-plugin=./$generator_plugin",
"--plugin_out",
"$generator_plugin_options$rel_out_dir", # Separated by colon.
]
}
deps = [
protoc_label,
]
# The deps may have steps that have to run before running protobuf.
if (defined(invoker.deps)) {
deps += invoker.deps
}
}
if (defined(invoker.component_build_force_source_set) &&
invoker.component_build_force_source_set &&
is_component_build) {
link_target_type = "source_set"
} else {
link_target_type = "static_library"
}
target(link_target_type, target_name) {
forward_variables_from(invoker,
[
"visibility",
"defines",
])
sources = get_target_outputs(":$action_name")
if (defined(invoker.extra_configs)) {
configs += invoker.extra_configs
}
public_configs = [ "//third_party/protobuf:using_proto" ]
# If using built-in cc generator the resulting headers reference headers
# within protobuf_lite, hence dependencies require those headers too.
# In case of generator plugin such issues should be resolved by invoker.
if (!defined(invoker.generate_cc) || invoker.generate_cc) {
public_deps = [
"//third_party/protobuf:protobuf_lite",
]
}
deps = [
":$action_name",
]
# This will link any libraries in the deps (the use of invoker.deps in the
# action won't link it).
if (defined(invoker.deps)) {
deps += invoker.deps
}
}
}