# Copyright 2022 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/fuzzing/internal/library_fuzzer.gni")

# Creates a fuzzer binary.
#
# When built in a fuzzer toolchain variant, this template produces a fuzzer that uses libfuzzer as
# its fuzzing engine, and that is linked directly against one or more target libraries in the same
# process. The fuzzer generates and tests inputs in a loop, automatically discovering code paths and
# finding bugs.
#
# When built with a non-fuzzer toolchain variant, it produces a "fuzzer test" that exercises the
# same code as above with a set of fixed inputs. This is useful for ensuring the fuzzer code is
# buildable and, if inputs that previously caused are added to the fixed set, acting as a regression
# test.
#
# Parameters are the same as `executable` except that:
#   $testonly cannot be set
#   $variant_selector_target_type cannot be set
#
template("fuchsia_library_fuzzer") {
  # Include the fuzzer executable.
  fuzzer_target = "${target_name}_bin"
  fuzzer_name = target_name
  if (defined(invoker.output_name)) {
    fuzzer_name = invoker.output_name
  }

  library_fuzzer(fuzzer_target) {
    output_name = fuzzer_name
    forward_variables_from(invoker,
                           "*",
                           [
                             "configs",
                             "output_name",
                             "target_type",
                             "visibility",
                           ])
    target_configs = invoker.configs
  }

  # Assemble the group.
  group(target_name) {
    testonly = true
    forward_variables_from(invoker, [ "visibility" ])
    deps = [
      ":$fuzzer_target",
      "//src/sys/fuzzing/libfuzzer",
    ]
  }
}

set_defaults("fuchsia_library_fuzzer") {
  configs = default_executable_configs
}