2025-01-20 11:24:16 -08:00

97 lines
3.9 KiB
Python

BUILD_FILE_CONTENT_TEMPLATE = """
package(default_visibility = ['//visibility:public'])
exports_files(['emscripten_config'])
"""
EMBUILDER_CONFIG_TEMPLATE = """
CACHE = '{cache}'
BINARYEN_ROOT = '{binaryen_root}'
LLVM_ROOT = '{llvm_root}'
"""
def get_root_and_script_ext(repository_ctx):
if repository_ctx.os.name.startswith('linux'):
if 'amd64' in repository_ctx.os.arch or 'x86_64' in repository_ctx.os.arch:
return (repository_ctx.path(Label("@emscripten_bin_linux//:BUILD.bazel")).dirname, '')
elif 'aarch64' in repository_ctx.os.arch:
return (repository_ctx.path(Label("@emscripten_bin_linux_arm64//:BUILD.bazel")).dirname, '')
else:
fail('Unsupported architecture for Linux')
elif repository_ctx.os.name.startswith('mac'):
if 'amd64' in repository_ctx.os.arch or 'x86_64' in repository_ctx.os.arch:
return (repository_ctx.path(Label("@emscripten_bin_mac//:BUILD.bazel")).dirname, '')
elif 'aarch64' in repository_ctx.os.arch:
return (repository_ctx.path(Label("@emscripten_bin_mac_arm64//:BUILD.bazel")).dirname, '')
else:
fail('Unsupported architecture for MacOS')
elif repository_ctx.os.name.startswith('windows'):
return (repository_ctx.path(Label("@emscripten_bin_win//:BUILD.bazel")).dirname, '.bat')
else:
fail('Unsupported operating system')
def _emscripten_cache_impl(repository_ctx):
# Read the default emscripten configuration file
default_config = repository_ctx.read(
repository_ctx.path(
Label("@emsdk//emscripten_toolchain:default_config")
)
)
if repository_ctx.attr.targets or repository_ctx.attr.configuration:
root, script_ext = get_root_and_script_ext(repository_ctx)
llvm_root = root.get_child("bin")
cache = repository_ctx.path("cache")
# Create configuration file
embuilder_config_content = EMBUILDER_CONFIG_TEMPLATE.format(
cache=cache,
binaryen_root=root,
llvm_root=llvm_root,
)
repository_ctx.file("embuilder_config", embuilder_config_content)
embuilder_config_path = repository_ctx.path("embuilder_config")
embuilder_path = "{}{}".format(root.get_child("emscripten").get_child("embuilder"), script_ext)
# Prepare the command line
if repository_ctx.attr.targets:
targets = repository_ctx.attr.targets
else:
# If no targets are requested, build everything
targets = ["ALL"]
flags = ["--em-config", embuilder_config_path] + repository_ctx.attr.configuration
embuilder_args = [embuilder_path] + flags + ["build"] + targets
# Run embuilder
repository_ctx.report_progress("Building secondary cache")
result = repository_ctx.execute(
embuilder_args,
quiet=True,
environment = {
"EM_IGNORE_SANITY": "1",
"EM_NODE_JS": "empty",
}
)
if result.return_code != 0:
fail("Embuilder exited with a non-zero return code")
# Override Emscripten's cache with the secondary cache
default_config += "CACHE = '{}'\n".format(cache)
# Create the configuration file for the toolchain and export
repository_ctx.file('emscripten_config', default_config)
repository_ctx.file('BUILD.bazel', BUILD_FILE_CONTENT_TEMPLATE)
_emscripten_cache = repository_rule(
implementation = _emscripten_cache_impl,
attrs = {
"configuration": attr.string_list(),
"targets": attr.string_list(),
},
local = True
)
def register_emscripten_toolchains(cache = {}):
_emscripten_cache(
name = "emscripten_cache",
configuration = cache["configuration"] if "configuration" in cache else [],
targets = cache["targets"] if "targets" in cache else [],
)
native.register_toolchains(str(Label("//emscripten_toolchain:cc-toolchain-wasm")))