| # Copyright 2019 The Fuchsia Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| import("$zx/public/gn/config/levels.gni") |
| import("$zx/public/gn/config/standard.gni") |
| import("$zx/public/gn/toolchain/c_utils.gni") |
| import("$zx/public/gn/toolchain/environment.gni") |
| import("$zx/public/gn/toolchain/environment_redirect.gni") |
| |
| # userboot gets its own toolchain for its special build requirements. |
| if (current_toolchain == default_toolchain) { |
| # Define the special toolchain itself only in the default toolchain. |
| foreach(cpu, standard_fuchsia_cpus) { |
| environment("userboot") { |
| cpu = cpu |
| configs += standard_fuchsia_configs + [ ":userboot_config" ] |
| |
| # This doesn't get a separate shlib sub-toolchain, but the main one |
| # can do loadable_module(). |
| solink = true |
| |
| if (opt_level < 2) { |
| # userboot doesn't stay sufficiently pure without optimization. |
| toolchain_args = { |
| opt_level = 2 |
| } |
| } |
| |
| # userboot can't use any instrumentation runtimes. |
| exclude_variant_tags = [ "instrumented" ] |
| } |
| } |
| } else if (toolchain.environment == "userboot") { |
| # Everything in userboot gets compiled this way. |
| config("userboot_config") { |
| configs = [ |
| "$zx/public/gn/config:user", |
| "$zx/public/gn/config:static-libc++", |
| "$zx/public/gn/config:no_sanitizers", |
| ] |
| |
| cflags = [ |
| # -fPIE is the default in Clang, but not in GCC. |
| "-fpie", |
| |
| # Everything is statically linked together with no PLT or GOT. |
| # No $inputs needed here since the depfile will list it. |
| "-include", |
| rebase_path("$zx/kernel/include/hidden.h", root_build_dir), |
| ] |
| defines = [ |
| "HIDDEN", |
| "WITH_LZ4_NOALLOC", |
| ] |
| } |
| |
| # This is the output of target ":gen-vdso-syms-ld", below. |
| vdso_syms_ld = "$target_gen_dir/vdso-syms.ld" |
| |
| # userboot is a reentrant DSO (no writable segment) with an entry point. |
| loadable_module("userboot") { |
| sources = [ |
| "bootdata.cpp", |
| "bootfs.cpp", |
| "loader-service.cpp", |
| "option.cpp", |
| "start.cpp", |
| "userboot-elf.cpp", |
| "util.cpp", |
| ] |
| configs += [ "$zx/public/gn/config:rodso" ] |
| ldflags = [ "-Wl,-e,_start" ] |
| libs = [ vdso_syms_ld ] |
| deps = [ |
| ":gen-vdso-syms-ld", |
| "$zx/system/ulib/bootdata", |
| "$zx/system/ulib/elf-psabi", |
| "$zx/system/ulib/elfload", |
| "$zx/system/ulib/ldmsg", |
| "$zx/system/ulib/processargs", |
| "$zx/system/ulib/zircon:headers", |
| "$zx/system/ulib/zircon-internal", |
| "$zx/third_party/ulib/lz4", |
| "$zx/third_party/ulib/musl/src/string:minimal_str", |
| "$zx/third_party/ulib/musl/src/string:stdmem", |
| ] |
| } |
| |
| # This generated header lists all the ABI symbols in the vDSO with their |
| # addresses. It's used to generate vdso-syms.ld, below. |
| toolchain_utils_action("gen-vdso-syms-header") { |
| visibility = [ ":gen-vdso-syms-ld" ] |
| |
| # Use the same link_output_rspfile() that lib/vdso uses to embed it, |
| # so we're sure to be getting the exact same binary. |
| deps = [ |
| "$zx/kernel/lib/vdso:gen-vdso-code-header.rsp", |
| ] |
| vdso_gen_dir = get_label_info(deps[0], "target_gen_dir") |
| sources = [ |
| "$vdso_gen_dir/gen-vdso-code-header.rsp", |
| ] |
| |
| outputs = [ |
| "$target_gen_dir/vdso-syms.h", |
| ] |
| depfile = "${outputs[0]}.d" |
| utils = [ "nm" ] |
| script = "$zx/scripts/shlib-symbols" |
| args = [ |
| "-a", |
| "@" + rebase_path(sources[0], root_build_dir), |
| rebase_path(outputs[0], root_build_dir), |
| rebase_path(depfile, root_build_dir), |
| ] |
| metadata = { |
| generated_sources = rebase_path(outputs, root_build_dir) |
| } |
| } |
| |
| # This generated linker script defines symbols for each vDSO entry point |
| # giving the relative address where it will be found at runtime. With |
| # this hack, the userboot code doesn't need to do any special work to |
| # find the vDSO and its entry points, keeping the code far simpler. |
| toolchain_utils_action("gen-vdso-syms-ld") { |
| visibility = [ ":*" ] |
| outputs = [ |
| vdso_syms_ld, |
| ] |
| deps = [ |
| ":gen-vdso-syms-header", |
| ] |
| sources = get_target_outputs(deps[0]) |
| inputs = [ |
| "vdso-syms.ld.h", |
| ] |
| utils = [ "cc" ] |
| args = [ |
| "-o", |
| rebase_path(outputs[0], root_build_dir), |
| "-E", |
| "-P", |
| "-include", |
| rebase_path(inputs[0], root_build_dir), |
| rebase_path(sources[0], root_build_dir), |
| ] |
| } |
| } else { |
| # In any other toolchain, just redirect to the proper toolchain. |
| environment_redirect("userboot") { |
| environment_label = ":userboot" |
| direct = true |
| deps = [ |
| ":userboot", |
| ] |
| } |
| |
| group("user") { |
| deps = [ |
| ":userboot", |
| ] |
| } |
| } |