Optionally unbundle OpenH264

Adds GN logic to use system OpenH264 on Linux.

Change-Id: I2904a45c34e86325e0f6fc77a67c1a204e832556
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

2 files changed, 53 insertions, 6 deletions

diff --git a/chromium/third_party/openh264/BUILD.gn b/chromium/third_party/openh264/BUILD.gn
index 7b9d4588b80..e33b5233b5b 100644
--- a/chromium/third_party/openh264/BUILD.gn
+++ b/chromium/third_party/openh264/BUILD.gn
@@ -2,7 +2,9 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//build/config/linux/pkg_config.gni")
 import("//build/config/sanitizers/sanitizers.gni")
+import("//build/shim_headers.gni")
 import("//third_party/openh264/openh264_args.gni")
 import("//third_party/openh264/openh264_sources.gni")
 import("//third_party/yasm/yasm_assemble.gni")
@@ -101,7 +103,7 @@ if (use_assembler) {
   }
 }  # if (is_win || is_linux)
 
-source_set("common") {
+source_set("bundled_common") {
   sources = openh264_common_sources
   include_dirs = openh264_common_include_dirs
 
@@ -124,7 +126,7 @@ source_set("common") {
   }
 }
 
-source_set("processing") {
+source_set("bundled_processing") {
   sources = openh264_processing_sources
   include_dirs = openh264_processing_include_dirs
 
@@ -132,7 +134,7 @@ source_set("processing") {
   configs += [ "//build/config/compiler:no_chromium_code" ]
   configs += [ ":config" ]
   deps = [
-    ":common",
+    ":bundled_common",
   ]
   if (use_assembler) {
     defines = [ "X86_ASM" ]
@@ -140,7 +142,7 @@ source_set("processing") {
   }
 }
 
-source_set("encoder") {
+source_set("bundled_encoder") {
   sources = openh264_encoder_sources
   include_dirs = openh264_encoder_include_dirs
 
@@ -154,11 +156,55 @@ source_set("encoder") {
     configs -= [ "//build/config/clang:extra_warnings" ]
   }
   deps = [
-    ":common",
-    ":processing",
+    ":bundled_common",
+    ":bundled_processing",
   ]
   if (use_assembler) {
     defines = [ "X86_ASM" ]
     deps += [ ":openh264_encoder_yasm" ]
   }
 }
+
+if (use_system_openh264) {
+  pkg_config("system_openh264") {
+    packages = [ "openh264" ]
+  }
+}
+
+shim_headers("openh264_shim") {
+  prefix = "wels/"
+  root_path = "src/codec/api/svc"
+  headers = [
+    "codec_api.h",
+    "codec_app_def.h",
+    "codec_def.h",
+    "codec_ver.h",
+  ]
+}
+
+group("common") {
+  if (use_system_openh264) {
+    deps = [ ":openh264_shim" ]
+    public_configs = [ ":system_openh264" ]
+  } else {
+    public_deps = [ ":bundled_common" ]
+  }
+}
+
+group("processing") {
+  if (use_system_openh264) {
+    deps = [ ":openh264_shim" ]
+    public_configs = [ ":system_openh264" ]
+  } else {
+    public_deps = [ ":bundled_processing" ]
+  }
+}
+
+group("encoder") {
+  if (use_system_openh264) {
+    deps = [ ":openh264_shim" ]
+    public_configs = [ ":system_openh264" ]
+  } else {
+    public_deps = [ ":bundled_encoder" ]
+  }
+}
diff --git a/chromium/third_party/openh264/openh264_args.gni b/chromium/third_party/openh264/openh264_args.gni
index b7558fbd5bf..a1d20380fc3 100644
--- a/chromium/third_party/openh264/openh264_args.gni
+++ b/chromium/third_party/openh264/openh264_args.gni
@@ -9,4 +9,5 @@ declare_args() {
   # CHECK THE OPENH264 LICENSE/PATENT BEFORE BUILDING, see
   # http://www.openh264.org/.
   use_openh264 = false
+  use_system_openh264 = false
 }