zircon/system/ulib/trace-engine/BUILD.gn

# 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.

# Three copies of libtrace-engine are built:
# 1) Shared library for use by userspace tracing.
# 2) Static library for use by userspace tracing.
# 3) Static library to be linked into libdriver.so for use by driver tracing.
#
# N.B. Please DO NOT use (2) unless you KNOW you need to. Generally you do not.
# If in doubt, ask. (2) is for very special circumstances where
# libtrace-engine.so is not available.

trace_engine_headers = [
  # buffer_internal.h is not here on purpose.
  "lib/trace-engine/context.h",
  "lib/trace-engine/fields.h",
  "lib/trace-engine/handler.h",
  "lib/trace-engine/instrumentation.h",
  "lib/trace-engine/types.h",
]

trace_engine_header_deps = [
  # <trace-engine/handler.h> has #include <lib/async/dispatcher.h>.
  "$zx/system/ulib/async:headers",
]

template("trace_engine_library") {
  zx_library(target_name) {
    forward_variables_from(invoker, "*")

    if (defined(extra_configs)) {
      configs += extra_configs
    }

    sdk_headers = trace_engine_headers
    public_deps = trace_engine_header_deps

    sources = [
      "context.cc",
      "context_api.cc",
      "context_impl.h",
      "engine.cc",
      "hash_table.h",
      "nonce.cc",
    ]
    deps = [
      "$zx/system/ulib/async:async-cpp",
      "$zx/system/ulib/fbl",
      "$zx/system/ulib/zircon",
      "$zx/system/ulib/zx",
    ]
  }
}

# The default version for the normal case.
trace_engine_library("trace-engine") {
  sdk = "shared"
  sdk_publishable = true
  extra_configs = [ "$zx_build/public/gn/config:static-libc++" ]
  shared = true
  static = false
}

# A special version for programs and shared libraries that can't use
# libtrace-engine.so, e.g., because it is unavailable.
# N.B. Please verify that you really need this before using it.
# Generally you DO NOT want to use this.
trace_engine_library("trace-engine-static") {
  sdk = "static"
  defines = [ "STATIC_LIBRARY" ]
}

# And again, but this time for drivers.
# This gets linked into libdriver.so.
trace_engine_library("trace-engine-driver") {
  sdk = "static"
  defines = [ "DDK_TRACING" ]
}

# Header-only source package for use by trace-provider:handler,
# which is engine-agnostic.
zx_library("trace-engine-headers-for-handler") {
  sdk = "source"
  sdk_headers = trace_engine_headers
  public_deps = trace_engine_header_deps
  sources = []
}

# Header-only source package for use by exported trace-reader package.
# This code also runs on the host.
zx_library("trace-engine-headers-for-reader") {
  sdk = "source"
  host = true
  sdk_headers = [
    "lib/trace-engine/fields.h",
    "lib/trace-engine/types.h",
  ]
  sources = []
}