esp-open-rtos/bazel/cc_static_library.bzl

134 lines
4.6 KiB
Python

"""Provides a rule that outputs a monolithic static library."""
load("@bazel_tools//tools/cpp:toolchain_utils.bzl", "find_cpp_toolchain")
TOOLS_CPP_REPO = "@bazel_tools"
def _cc_static_library_impl(ctx):
output_lib = ctx.actions.declare_file("{}.a".format(ctx.attr.name))
output_flags = ctx.actions.declare_file("{}.link".format(ctx.attr.name))
cc_toolchain = find_cpp_toolchain(ctx)
# Populate the feature configuration. This is used by the various cc library
# functions to generate contexts.
feature_configuration = cc_common.configure_features(
ctx = ctx,
cc_toolchain = cc_toolchain,
requested_features = ctx.features,
unsupported_features = ctx.disabled_features
)
lib_sets = []
lib_inputs = []
unique_flags = {}
merged_compilation_context = cc_common.merge_compilation_contexts(
compilation_contexts = [dep[CcInfo].compilation_context for dep in ctx.attr.deps]
)
for dep in ctx.attr.deps:
if hasattr(dep[CcInfo].linking_context.linker_inputs, "to_list"):
lib_inputs.append(dep[CcInfo].linking_context.linker_inputs.to_list())
else:
lib_inputs.append(dep[CcInfo].linking_context.linker_inputs)
for lib in dep[CcInfo].linking_context.linker_inputs.to_list():
if hasattr(lib.libraries, "to_list"):
lib_sets.append(lib.libraries)
else:
lib_sets.append(depset(direct = lib.libraries))
unique_flags.update({
flag: None
for flag in lib.user_link_flags
})
libraries_to_link = depset(transitive = lib_sets)
link_flags = unique_flags.keys()
libs = []
libs.extend([lib.pic_static_library for lib in libraries_to_link.to_list() if lib.pic_static_library])
libs.extend([
lib.static_library
for lib in libraries_to_link.to_list()
if lib.static_library and not lib.pic_static_library
])
script_file = ctx.actions.declare_file("{}.mri".format(ctx.attr.name))
commands = ["create {}".format(output_lib.path)]
for lib in libs:
commands.append("addlib {}".format(lib.path))
commands.append("save")
commands.append("end")
ctx.actions.write(
output = script_file,
content = "\n".join(commands) + "\n",
)
ar_tool = cc_common.get_tool_for_action(
feature_configuration = feature_configuration,
action_name = "ar",
)
ctx.actions.run_shell(
command = "{} -M < {}".format(ar_tool, script_file.path),
inputs = [script_file] + libs + cc_toolchain.all_files.to_list(),
outputs = [output_lib],
mnemonic = "ArMerge",
progress_message = "Merging static library {}".format(output_lib.path),
)
ctx.actions.write(
output = output_flags,
content = "\n".join(link_flags) + "\n",
)
# With the library in hand, the next step is to set up information for
# Bazel's C/C++ library to utilize the newly-created library.
library_to_link = cc_common.create_library_to_link(
actions = ctx.actions,
feature_configuration = feature_configuration,
static_library = output_lib,
#user_link_flags = ['fooxbar']
)
linker_input = cc_common.create_linker_input(
libraries = depset([library_to_link]),
owner = ctx.label,
)
linking_context = cc_common.create_linking_context(
linker_inputs = depset([linker_input])
)
# CcInfo is what is actually passed to future targets. We may need to merge
# this with the dependency's original info in order for builds to complete.
# Not sure yet.
this_cc_info = CcInfo(compilation_context = merged_compilation_context, linking_context = linking_context)
cc_infos = [this_cc_info]
# print(this_cc_info.linking_context)
# print(ctx.attr.library[CcInfo].compilation_context)
# print(ctx.attr.library[CcInfo].linking_context)
# cc_infos.append(ctx.attr.library[CcInfo])
merged_cc_info = cc_common.merge_cc_infos(direct_cc_infos = [this_cc_info], cc_infos = cc_infos)
# print(merged_cc_info.linking_context)
return [
DefaultInfo(files = depset([output_lib])),
merged_cc_info
]
cc_static_library = rule(
implementation = _cc_static_library_impl,
attrs = {
"deps": attr.label_list(),
"_cc_toolchain": attr.label(
default = TOOLS_CPP_REPO + "//tools/cpp:current_cc_toolchain",
),
},
toolchains = [TOOLS_CPP_REPO + "//tools/cpp:toolchain_type"],
fragments = ["cpp"],
incompatible_use_toolchain_transition = True,
)