Build WebRTC with data channel only.

webrtc/media/BUILD.gn

Index: webrtc/media/BUILD.gn
diff --git a/webrtc/media/BUILD.gn b/webrtc/media/BUILD.gn
index 9c76d8c44e73bd6235807e570a2a919f62a75bed..723ae33639bb480abdcfefc7c645e2b31863bb40 100644
--- a/webrtc/media/BUILD.gn
+++ b/webrtc/media/BUILD.gn
@@ -23,13 +23,40 @@ config("rtc_media_defines_config") {
   ]
 }
 
-rtc_static_library("rtc_media_base") {
+config("rtc_media_warnings_config") {
+  # GN orders flags on a target before flags from configs. The default config
+  # adds these flags so to cancel them out they need to come from a config and
+  # cannot be on the target directly.
+  if (!is_win) {
+    cflags = [ "-Wno-deprecated-declarations" ]
+  }
+}
+
+rtc_source_set("rtc_media_base_audio") {
+  sources = [
+    "base/audiosource.h",
+  ]
+}
+
+rtc_source_set("rtc_media_base_video") {
+  deps = [
+    "../api:video_frame_api",
+    "../common_video:common_video",
+  ]
+}
+
+# This target is used to build WebRTC without audio and video support but it
+# contains more than just datachannel related classes.
+# TODO(zhihuang): Split this target further into a target containing only
+# datachannel related classes and a target containing common classes for media
+# base.
+rtc_source_set("rtc_media_base_data") {
   # TODO(kjellander): Remove (bugs.webrtc.org/6828)
   # Enabling GN check triggers cyclic dependency error:
-  #   //webrtc/media:rtc_media_base ->
-  #   //webrtc/pc:rtc_pc ->
-  #   //webrtc/media:media ->
-  #   //webrtc/media:rtc_media_base
+  #   //webrtc/media:rtc_media_base_data ->
+  #   //webrtc/pc:rtc_pc_base ->
+  #   //webrtc/media:rtc_data ->
+  #   //webrtc/media:rtc_media_base_data
   check_includes = false
   defines = []
   libs = []
@@ -37,11 +64,12 @@ rtc_static_library("rtc_media_base") {
   sources = [
     "base/adaptedvideotracksource.cc",
     "base/adaptedvideotracksource.h",
-    "base/audiosource.h",
     "base/codec.cc",
     "base/codec.h",
     "base/cryptoparams.h",
     "base/device.h",
+    "base/h264_profile_level_id.cc",
+    "base/h264_profile_level_id.h",
     "base/mediachannel.h",
     "base/mediaconstants.cc",
     "base/mediaconstants.h",
@@ -87,13 +115,8 @@ rtc_static_library("rtc_media_base") {
   deps += [
     "..:webrtc_common",
     "../api:libjingle_peerconnection_api",
-    "../api:video_frame_api",
-    "../api/audio_codecs:audio_codecs_api",
-    "../api/audio_codecs:builtin_audio_encoder_factory",
     "../base:rtc_base",
     "../base:rtc_base_approved",
-    "../call:call_interfaces",
-    "../common_video:common_video",
     "../p2p",
   ]
 
@@ -102,14 +125,15 @@ rtc_static_library("rtc_media_base") {
   }
 }
 
-rtc_static_library("rtc_media") {
-  # TODO(kjellander): Remove (bugs.webrtc.org/6828)
-  # Enabling GN check triggers cyclic dependency error:
-  #   //webrtc/media:media ->
-  #   //webrtc/media:rtc_media ->
-  #   //webrtc/pc:rtc_pc ->
-  #   //webrtc/media:media
-  check_includes = false
+rtc_source_set("rtc_media_base") {
+  public_deps = [
+    ":rtc_media_base_audio",
+    ":rtc_media_base_data",
+    ":rtc_media_base_video",
+  ]
+}
+
+rtc_static_library("rtc_audio_video") {
   defines = []
   libs = []
   deps = []
@@ -145,15 +169,9 @@ rtc_static_library("rtc_media") {
     "engine/webrtcvoe.h",
     "engine/webrtcvoiceengine.cc",
     "engine/webrtcvoiceengine.h",
-    "sctp/sctptransportinternal.h",
   ]
 
-  if (rtc_enable_sctp) {
-    sources += [
-      "sctp/sctptransport.cc",
-      "sctp/sctptransport.h",
-    ]
-  }
+  configs += [ ":rtc_media_warnings_config" ]
 
   if (!build_with_chromium && is_clang) {
     # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
@@ -191,15 +209,6 @@ rtc_static_library("rtc_media") {
     include_dirs += [ "$rtc_libyuv_dir/include" ]
   }
 
-  if (rtc_enable_sctp && rtc_build_usrsctp) {
-    include_dirs += [
-      # TODO(jiayl): move this into the public_configs of
-      # //third_party/usrsctp/BUILD.gn.
-      "//third_party/usrsctp/usrsctplib",
-    ]
-    deps += [ "//third_party/usrsctp" ]
-  }
-
   public_configs = []
   if (build_with_chromium) {
     deps += [ "../modules/video_capture:video_capture" ]
@@ -213,16 +222,22 @@ rtc_static_library("rtc_media") {
     deps += [ "../modules/audio_processing/aec_dump:null_aec_dump_factory" ]
   }
   deps += [
-    ":rtc_media_base",
+    ":rtc_media_base_audio",
+    ":rtc_media_base_data",
+    ":rtc_media_base_video",
+    "..:video_stream_api",
     "..:webrtc_common",
     "../api:call_api",
+    "../api:libjingle_peerconnection_api",
     "../api:transport_api",
     "../api:video_frame_api",
     "../api/audio_codecs:audio_codecs_api",
     "../api/audio_codecs:builtin_audio_decoder_factory",
+    "../api/audio_codecs:builtin_audio_encoder_factory",
     "../api/video_codecs:video_codecs_api",
     "../base:rtc_base",
     "../base:rtc_base_approved",
+    "../base:rtc_task_queue",
     "../call",
     "../common_video:common_video",
     "../modules/audio_coding:rent_a_codec",
@@ -236,12 +251,68 @@ rtc_static_library("rtc_media") {
     "../modules/video_coding:webrtc_vp8",
     "../modules/video_coding:webrtc_vp9",
     "../p2p:rtc_p2p",
+    "../pc:rtc_pc_base",
     "../system_wrappers",
     "../video",
     "../voice_engine",
   ]
 }
 
+rtc_static_library("rtc_data") {
+  defines = []
+  deps = []
+
+  if (rtc_enable_sctp) {
+    sources = [
+      "sctp/sctptransport.cc",
+      "sctp/sctptransport.h",
+      "sctp/sctptransportinternal.h",
+    ]
+  }
+
+  configs += [ ":rtc_media_warnings_config" ]
+
+  if (!build_with_chromium && is_clang) {
+    # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
+    suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
+  }
+
+  if (is_win) {
+    cflags = [
+      "/wd4245",  # conversion from "int" to "size_t", signed/unsigned mismatch.
+      "/wd4267",  # conversion from "size_t" to "int", possible loss of data.
+      "/wd4389",  # signed/unsigned mismatch.
+    ]
+  }
+
+  if (rtc_enable_sctp && rtc_build_usrsctp) {
+    include_dirs = [
+      # TODO(jiayl): move this into the public_configs of
+      # //third_party/usrsctp/BUILD.gn.
+      "//third_party/usrsctp/usrsctplib",
+    ]
+    deps += [ "//third_party/usrsctp" ]
+  }
+
+  deps += [
+    ":rtc_media_base_data",
+    "..:webrtc_common",
+    "../api:call_api",
+    "../api:transport_api",
+    "../base:rtc_base",
+    "../base:rtc_base_approved",
+    "../p2p:rtc_p2p",
+    "../system_wrappers",
+  ]
+}
+
+rtc_source_set("rtc_media") {
+  public_deps = [
+    ":rtc_audio_video",
+    ":rtc_data",
+  ]
+}
+

[Taylor Brandstetter, 2017/06/14 01:54:16]

Given the current approach of this CL, some of these build targets now seem
unnecessary. I think all we really need for the time being are rtc_media,
rtc_audio_video, rtc_data, and rtc_media_base. Could the "common_video"
dependency be pushed up to "rtc_audio_video"?

[Zhi Huang, 2017/06/14 06:57:01]

Done. Now we only have rtc_media_base.

 if (rtc_include_tests) {
   config("rtc_unittest_main_config") {
     # GN orders flags on a target before flags from configs. The default config