# 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.

import("//build_overrides/build.gni")
import("//build/config/chrome_build.gni")
import("//build/config/chromecast_build.gni")
import("//build/config/clang/clang.gni")
import("//build/config/sanitizers/sanitizers.gni")
import("//build/toolchain/toolchain.gni")

if (is_ios) {
  import("//build/config/ios/ios_sdk.gni")
}

# Contains the dependencies needed for sanitizers to link into
# executables and shared_libraries. Unconditionally depend upon
# "//build/config:exe_and_shlib_deps" to pull in this target.
group("deps") {
  visibility = [ "//build/config:exe_and_shlib_deps" ]
  if (using_sanitizer) {
    public_configs = [
      ":sanitizer_options_link_helper",

      # Even when a target removes default_sanitizer_flags, it may be depending
      # on a library that did not remove default_sanitizer_flags. Thus, we need
      # to add the ldflags here as well as in default_sanitizer_flags.
      ":default_sanitizer_ldflags",
    ]
    deps = [
      ":options_sources",
    ]
    if (is_win) {
      exe = ".exe"
    } else {
      exe = ""
    }
    data = [
      "//tools/valgrind/asan/",
      "$clang_base_path/bin/llvm-symbolizer${exe}",
    ]
    if (use_prebuilt_instrumented_libraries ||
        use_locally_built_instrumented_libraries) {
      deps += [ "//third_party/instrumented_libraries:deps" ]
    }

    # ASAN is supported on iOS but the runtime library depends on the compiler
    # used (Chromium version of clang versus Xcode version of clang). Only copy
    # the ASAN runtime on iOS if building with Chromium clang.
    if (is_win || is_mac || (is_ios && !use_xcode_clang)) {
      data_deps = [
        ":copy_asan_runtime",
      ]
    }
    if (is_mac || (is_ios && !use_xcode_clang)) {
      public_deps = [
        ":asan_runtime_bundle_data",
      ]
    }
  }
}

if ((is_mac || is_win || (is_ios && !use_xcode_clang)) && using_sanitizer) {
  if (is_mac) {
    _clang_rt_dso_path = "darwin/libclang_rt.asan_osx_dynamic.dylib"
  } else if (is_ios) {
    _clang_rt_dso_path = "darwin/libclang_rt.asan_iossim_dynamic.dylib"
  } else if (is_win && target_cpu == "x86") {
    _clang_rt_dso_path = "windows/clang_rt.asan_dynamic-i386.dll"
  } else if (is_win && target_cpu == "x64") {
    _clang_rt_dso_path = "windows/clang_rt.asan_dynamic-x86_64.dll"
  }

  _clang_rt_dso_full_path =
      "$clang_base_path/lib/clang/$clang_version/lib/$_clang_rt_dso_path"

  if (!is_ios) {
    copy("copy_asan_runtime") {
      sources = [
        _clang_rt_dso_full_path,
      ]
      outputs = [
        "$root_out_dir/{{source_file_part}}",
      ]
    }
  } else {
    # On iOS, the runtime library need to be code signed (adhoc signature)
    # starting with Xcode 8, so use an action instead of a copy on iOS.
    action("copy_asan_runtime") {
      script = "//build/config/ios/codesign.py"
      sources = [
        _clang_rt_dso_full_path,
      ]
      outputs = [
        "$root_out_dir/" + get_path_info(sources[0], "file"),
      ]
      args = [
        "code-sign-file",
        "--identity=" + ios_code_signing_identity,
        "--output=" + rebase_path(outputs[0], root_build_dir),
        rebase_path(sources[0], root_build_dir),
      ]
    }
  }

  if (is_mac || is_ios) {
    bundle_data("asan_runtime_bundle_data") {
      sources = get_target_outputs(":copy_asan_runtime")
      outputs = [
        "{{bundle_executable_dir}}/{{source_file_part}}",
      ]
      public_deps = [
        ":copy_asan_runtime",
      ]
    }
  }
}

config("sanitizer_options_link_helper") {
  if (is_mac || is_ios) {
    ldflags = [ "-Wl,-U,_sanitizer_options_link_helper" ]
  } else if (!is_win) {
    ldflags = [ "-Wl,-u_sanitizer_options_link_helper" ]
  }
}

static_library("options_sources") {
  # This is a static_library instead of a source_set, as it shouldn't be
  # unconditionally linked into targets.
  visibility = [
    ":deps",
    "//:gn_visibility",
  ]
  sources = [
    "//build/sanitizers/sanitizer_options.cc",
  ]

  # Don't compile this target with any sanitizer code. It can be called from
  # the sanitizer runtimes, so instrumenting these functions could cause
  # recursive calls into the runtime if there is an error.
  configs -= [ "//build/config/sanitizers:default_sanitizer_flags" ]

  if (is_asan) {
    if (!defined(asan_suppressions_file)) {
      asan_suppressions_file = "//build/sanitizers/asan_suppressions.cc"
    }
    sources += [ asan_suppressions_file ]
  }

  if (is_lsan) {
    if (!defined(lsan_suppressions_file)) {
      lsan_suppressions_file = "//build/sanitizers/lsan_suppressions.cc"
    }
    sources += [ lsan_suppressions_file ]
  }

  if (is_tsan) {
    if (!defined(tsan_suppressions_file)) {
      tsan_suppressions_file = "//build/sanitizers/tsan_suppressions.cc"
    }
    sources += [ tsan_suppressions_file ]
  }
}

# Applies linker flags necessary when either :deps or :default_sanitizer_flags
# are used.
config("default_sanitizer_ldflags") {
  visibility = [
    ":default_sanitizer_flags",
    ":deps",
  ]

  if (is_posix) {
    ldflags = []
    if (is_asan) {
      ldflags += [ "-fsanitize=address" ]
      if (is_mac) {
        # https://crbug.com/708707
        ldflags += [ "-fno-sanitize-address-use-after-scope" ]
      } else {
        ldflags += [ "-fsanitize-address-use-after-scope" ]
      }
    }
    if (is_lsan) {
      ldflags += [ "-fsanitize=leak" ]
    }
    if (is_tsan) {
      ldflags += [ "-fsanitize=thread" ]
    }
    if (is_msan) {
      ldflags += [ "-fsanitize=memory" ]
    }
    if (is_ubsan || is_ubsan_security) {
      ldflags += [ "-fsanitize=undefined" ]
    }
    if (is_ubsan_null) {
      ldflags += [ "-fsanitize=null" ]
    }
    if (is_ubsan_vptr) {
      ldflags += [ "-fsanitize=vptr" ]
    }

    if (use_sanitizer_coverage) {
      ldflags += [ "-fsanitize-coverage=$sanitizer_coverage_flags" ]
    }

    if (is_cfi && !is_nacl) {
      ldflags += [ "-fsanitize=cfi-vcall" ]
      if (use_cfi_cast) {
        ldflags += [
          "-fsanitize=cfi-derived-cast",
          "-fsanitize=cfi-unrelated-cast",
        ]
      }
      if (use_cfi_diag) {
        ldflags += [ "-fno-sanitize-trap=cfi" ]
        if (use_cfi_recover) {
          ldflags += [ "-fsanitize-recover=cfi" ]
        }
      }
    }
  } else if (is_win && is_asan) {
    # Windows directly calls link.exe instead of the compiler driver when
    # linking.  Hence, pass the runtime libraries instead of -fsanitize=address.
    # In the static-library build, libraries are different for executables
    # and dlls, see link_executable and link_shared_library below.
    # This here handles only the component build.
    if (target_cpu == "x64") {
      # Windows 64-bit. TODO(etienneb): Remove the assert when this is ready.
      if (is_component_build) {
        assert(false, "win/asan does not work in 64-bit yet")
        libs = [
          "clang_rt.asan_dynamic-x86_64.lib",
          "clang_rt.asan_dynamic_runtime_thunk-x86_64.lib",
        ]
      }
    } else {
      assert(target_cpu == "x86", "WinASan unsupported architecture")
      if (is_component_build) {
        libs = [
          "clang_rt.asan_dynamic-i386.lib",
          "clang_rt.asan_dynamic_runtime_thunk-i386.lib",
        ]
      }
    }
  }
}

config("common_sanitizer_flags") {
  cflags = []

  # Sanitizers need line table info for stack traces. They don't need type info
  # or variable info, so we can leave that out to speed up the build (unless
  # it's explicitly asked for by setting |sanitizer_keep_symbols| to true).
  if (using_sanitizer) {
    assert(is_clang, "sanitizers only supported with clang")
    assert(!is_official_build, "sanitizers not supported in official builds")

    if (!sanitizer_keep_symbols) {
      cflags += [ "-gline-tables-only" ]
    }

    cflags += [
      # Column info in debug data confuses Visual Studio's debugger, so don't
      # use this by default.  However, clusterfuzz needs it for good attribution
      # of reports to CLs, so turn it on there.
      "-gcolumn-info",
    ]

    # Disable frame pointer elimination for better stack traces.
    if (is_posix) {
      cflags += [ "-fno-omit-frame-pointer" ]
    } else {
      cflags += [ "/Oy-" ]
    }
  }
}

config("asan_flags") {
  cflags = []
  if (is_asan) {
    cflags += [ "-fsanitize=address" ]
    if (!is_mac) {
      cflags += [ "-fsanitize-address-use-after-scope" ]
    } else {
      # https://crbug.com/708707
      cflags += [ "-fno-sanitize-address-use-after-scope" ]
    }
    if (!asan_globals) {
      cflags += [
        "-mllvm",
        "-asan-globals=0",
      ]
    }
    if (is_win) {
      if (!defined(asan_win_blacklist_path)) {
        asan_win_blacklist_path =
            rebase_path("//tools/memory/asan/blacklist_win.txt", root_build_dir)
      }
      cflags += [ "-fsanitize-blacklist=$asan_win_blacklist_path" ]
    } else {
      # TODO(rnk): Remove this as discussed in http://crbug.com/427202.
      if (!defined(asan_blacklist_path)) {
        asan_blacklist_path =
            rebase_path("//tools/memory/asan/blacklist.txt", root_build_dir)
      }
      cflags += [ "-fsanitize-blacklist=$asan_blacklist_path" ]
    }
  }
}

config("link_executable") {
  if (is_asan && is_win && !is_component_build) {
    if (target_cpu == "x64") {
      # Windows 64-bit. TODO(etienneb): Remove the assert when this is ready.
      assert(false, "win/asan does not work in 64-bit yet")
      libs = [ "clang_rt.asan-x86_64.lib" ]
      ldflags = [ "-wholearchive:clang_rt.asan-x86_64.lib" ]
    } else {
      assert(target_cpu == "x86", "WinASan unsupported architecture")
      libs = [ "clang_rt.asan-i386.lib" ]
      ldflags = [ "-wholearchive:clang_rt.asan-i386.lib" ]
    }
  }
}

config("link_shared_library") {
  if (is_asan && is_win && !is_component_build) {
    if (target_cpu == "x64") {
      # Windows 64-bit. TODO(etienneb): Remove the assert when this is ready.
      assert(false, "win/asan does not work in 64-bit yet")
      libs = [ "clang_rt.asan_dll_thunk-x86_64.lib" ]
    } else {
      assert(target_cpu == "x86", "WinASan unsupported architecture")
      libs = [ "clang_rt.asan_dll_thunk-i386.lib" ]
    }
  }
}

config("cfi_flags") {
  cflags = []
  if (is_cfi && !is_nacl) {
    if (!defined(cfi_blacklist_path)) {
      cfi_blacklist_path =
          rebase_path("//tools/cfi/blacklist.txt", root_build_dir)
    }
    cflags += [
      "-fsanitize=cfi-vcall",
      "-fsanitize-blacklist=$cfi_blacklist_path",
    ]

    if (use_cfi_cast) {
      cflags += [
        "-fsanitize=cfi-derived-cast",
        "-fsanitize=cfi-unrelated-cast",
      ]
    }

    if (use_cfi_icall) {
      cflags += [ "-fsanitize=cfi-icall" ]
    }

    if (use_cfi_diag) {
      cflags += [ "-fno-sanitize-trap=cfi" ]
      if (is_win) {
        cflags += [
          "/Oy-",
          "/Ob0",
        ]
      } else {
        cflags += [
          "-fno-inline-functions",
          "-fno-inline",
          "-fno-omit-frame-pointer",
          "-O1",
        ]
      }
      if (use_cfi_recover) {
        cflags += [ "-fsanitize-recover=cfi" ]
      }
    } else {
      defines = [ "CFI_ENFORCEMENT_TRAP" ]
    }
  }
}

config("coverage_flags") {
  cflags = []

  if (use_sanitizer_coverage) {
    cflags += [
      "-fsanitize-coverage=$sanitizer_coverage_flags",
      "-mllvm",
      "-sanitizer-coverage-prune-blocks=1",
    ]
    if (current_cpu == "arm") {
      # http://crbug.com/517105
      cflags += [
        "-mllvm",
        "-sanitizer-coverage-block-threshold=0",
      ]
    }
    defines = [ "SANITIZER_COVERAGE" ]
  }
}

config("lsan_flags") {
  if (is_lsan) {
    cflags = [ "-fsanitize=leak" ]
  }
}

config("msan_flags") {
  if (is_msan) {
    assert(is_linux, "msan only supported on linux x86_64")
    if (!defined(msan_blacklist_path)) {
      msan_blacklist_path =
          rebase_path("//tools/msan/blacklist.txt", root_build_dir)
    }
    cflags = [
      "-fsanitize=memory",
      "-fsanitize-memory-track-origins=$msan_track_origins",
      "-fsanitize-blacklist=$msan_blacklist_path",
    ]
  }
}

config("tsan_flags") {
  if (is_tsan) {
    assert(is_linux, "tsan only supported on linux x86_64")
    if (!defined(tsan_blacklist_path)) {
      tsan_blacklist_path =
          rebase_path("//tools/memory/tsan_v2/ignores.txt", root_build_dir)
    }
    cflags = [
      "-fsanitize=thread",
      "-fsanitize-blacklist=$tsan_blacklist_path",
    ]
  }
}

config("ubsan_flags") {
  cflags = []
  if (is_ubsan) {
    if (!defined(ubsan_blacklist_path)) {
      ubsan_blacklist_path =
          rebase_path("//tools/ubsan/blacklist.txt", root_build_dir)
    }
    cflags += [
      # Yasm dies with an "Illegal instruction" error when bounds checking is
      # enabled. See http://crbug.com/489901
      # "-fsanitize=bounds",
      "-fsanitize=float-divide-by-zero",
      "-fsanitize=integer-divide-by-zero",
      "-fsanitize=null",
      "-fsanitize=object-size",
      "-fsanitize=return",
      "-fsanitize=returns-nonnull-attribute",
      "-fsanitize=shift-exponent",
      "-fsanitize=signed-integer-overflow",
      "-fsanitize=unreachable",
      "-fsanitize=vla-bound",
      "-fsanitize-blacklist=$ubsan_blacklist_path",
    ]

    # Chromecast ubsan builds fail to compile with these
    # experimental flags, so only add them to non-chromecast ubsan builds.
    if (!is_chromecast) {
      cflags += [
        # Employ the experimental PBQP register allocator to avoid slow
        # compilation on files with too many basic blocks.
        # See http://crbug.com/426271.
        "-mllvm",
        "-regalloc=pbqp",

        # Speculatively use coalescing to slightly improve the code generated
        # by PBQP regallocator. May increase compile time.
        "-mllvm",
        "-pbqp-coalescing",
      ]
    }
  }
}

config("ubsan_no_recover") {
  if (is_ubsan_no_recover) {
    cflags = [ "-fno-sanitize-recover=undefined" ]
  }
}

config("ubsan_security_flags") {
  if (is_ubsan_security) {
    if (!defined(ubsan_security_blacklist_path)) {
      ubsan_security_blacklist_path =
          rebase_path("//tools/ubsan/security_blacklist.txt", root_build_dir)
    }
    cflags = [
      "-fsanitize=signed-integer-overflow,shift,vptr,function,vla-bound",
      "-fsanitize-blacklist=$ubsan_security_blacklist_path",
    ]
  }
}

config("ubsan_null_flags") {
  if (is_ubsan_null) {
    cflags = [ "-fsanitize=null" ]
  }
}

config("ubsan_vptr_flags") {
  if (is_ubsan_vptr) {
    if (!defined(ubsan_vptr_blacklist_path)) {
      ubsan_vptr_blacklist_path =
          rebase_path("//tools/ubsan/vptr_blacklist.txt", root_build_dir)
    }
    cflags = [
      "-fsanitize=vptr",
      "-fsanitize-blacklist=$ubsan_vptr_blacklist_path",
    ]
  }
}

config("fuzzing_build_mode") {
  if (use_fuzzing_engine) {
    defines = [ "FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION" ]
  }
}

all_sanitizer_configs = [
  ":common_sanitizer_flags",
  ":coverage_flags",
  ":default_sanitizer_ldflags",
  ":asan_flags",
  ":cfi_flags",
  ":lsan_flags",
  ":msan_flags",
  ":tsan_flags",
  ":ubsan_flags",
  ":ubsan_no_recover",
  ":ubsan_null_flags",
  ":ubsan_security_flags",
  ":ubsan_vptr_flags",
  ":fuzzing_build_mode",
]

# This config is applied by default to all targets. It sets the compiler flags
# for sanitizer usage, or, if no sanitizer is set, does nothing.
#
# This needs to be in a separate config so that targets can opt out of
# sanitizers (by removing the config) if they desire. Even if a target
# removes this config, executables & shared libraries should still depend on
# :deps if any of their dependencies have not opted out of sanitizers.
# Keep this list in sync with default_sanitizer_flags_but_ubsan_vptr.
config("default_sanitizer_flags") {
  configs = all_sanitizer_configs
}

# This config is equivalent to default_sanitizer_flags, but excludes ubsan_vptr.
# This allows to selectively disable ubsan_vptr, when needed. In particular,
# if some third_party code is required to be compiled without rtti, which
# is a requirement for ubsan_vptr.
config("default_sanitizer_flags_but_ubsan_vptr") {
  configs = all_sanitizer_configs - [ ":ubsan_vptr_flags" ]
}

config("default_sanitizer_flags_but_coverage") {
  configs = all_sanitizer_configs - [ ":coverage_flags" ]
}