src/lib/trivial-allocator/BUILD.gn

# Copyright 2021 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("//build/components.gni")
import("//build/config/sanitizers/sanitizer_default_options.gni")
import("//build/cpp/cpp_fuzzer.gni")
import("//build/test.gni")
import("//build/testing/zbi_test.gni")
import("//build/zircon/migrated_targets.gni")

zx_library("trivial-allocator") {
  sdk = "source"
  sdk_headers = [
    "lib/trivial-allocator/basic-leaky-allocator.h",
    "lib/trivial-allocator/new.h",
    "lib/trivial-allocator/single-heap-allocator.h",
  ]

  public_deps = [
    "//sdk/lib/stdcompat",

    # <lib/trivial-allocator/new.h> has #include <fbl/alloc_checker.h>.
    "//zircon/system/ulib/fbl",
  ]

  sources = []
  deps = []

  if (is_kernel) {
    deps += [
      "//zircon/kernel/lib/ktl",
      "//zircon/kernel/lib/libc",
    ]
  }
}

# This provides no-op `operator delete` and `operator delete[]` functions with
# the signatures that are usually provided by the standard C++ library to call
# the libc allocator or the like.  If instead the only allocators available are
# from the trivial-allocator library, but pointers from the uses of `new` made
# possible by <lib/trivial-allocator/new.h> can be passed to `delete`, such as
# via std::unique_ptr or similar "smart pointer" types, then it's necessary to
# provide no-op deallocation functions.  Unlike those special `new` forms,
# there is no way to `delete` and indicate a specific allocator object.  So
# using this library is a catch-all hammer that prevents `delete` from doing
# any real deallocation regardless of what kind of `new` created the pointer.
#
# Note also: even without use of `delete`, C++ classes with virtual functions
# can produce implicit references in dead code that need to be satisfied.
#
# This library has no associated header since <new> already declares all the
# `operator delete` functions; even without that `delete` is always available.
# It's only provided to satisfy any link-time references with the no-op calls.
static_library("stub-delete") {
  sources = [ "stub-delete.cc" ]
  public_deps = [ ":suppress-lsan-for-stub-delete" ]

  if (is_kernel) {
    deps = [
      "//zircon/kernel/lib/ktl",
      "//zircon/kernel/lib/libc",
    ]
  }
}

# Everything is leaked when `delete` is a no-op.
sanitizer_extra_options("suppress-lsan-for-stub-delete") {
  visibility = [ ":*" ]
  args = [ "detect_leaks=0" ]
  output_name = "lsan_default_options"
  tags = [ "lsan" ]
}

# This is very similar, but instead of no-ops that leak memory when called,
# each entry point will panic (via ZX_PANIC) if it's ever called at runtime.
static_library("panic-delete") {
  sources = [ "panic-delete.cc" ]

  if (is_kernel) {
    deps = [
      "//zircon/kernel/lib/ktl",
      "//zircon/kernel/lib/libc",
    ]
  }
}

test("trivial-allocator-unittests") {
  sources = [
    "basic-leaky-allocator-tests.cc",
    "new-tests.cc",
    "single-heap-allocator-tests.cc",
  ]
  deps = [
    ":trivial-allocator",
    "//zircon/system/ulib/zxtest",
  ]
}

fuchsia_unittest_package("trivial-allocator-tests") {
  deps = [ ":trivial-allocator-unittests" ]
}

# This test is isolated since it no-op's out the `delete` usage done by the
# test harness itself.  For the same reason it's not really possible to have a
# test for panic-delete.
test("stub-delete-unittests") {
  deps = [
    ":trivial-allocator",
    "//zircon/system/ulib/zxtest",
  ]

  if ((is_fuchsia || current_os == "linux") &&
      toolchain_variant.tags + [ "replaces-allocator" ] -
      [ "replaces-allocator" ] == toolchain_variant.tags) {
    sources = [ "delete-tests.cc" ]
    deps += [ ":stub-delete" ]
  }
}

fuchsia_unittest_package("stub-delete-tests") {
  deps = [ ":stub-delete-unittests" ]
}

group("tests") {
  testonly = true

  deps = [
    ":stub-delete-tests",
    ":trivial-allocator-tests",
    ":trivial-allocator-unittests($host_toolchain)",
  ]
}