--- third_party/libusb/BUILD.gn.orig	2019-09-16 10:03:44 UTC
+++ third_party/libusb/BUILD.gn
@@ -1,174 +1,24 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
+# Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-# libusb is only used by //services/device/usb on Windows and macOS.
-assert(is_win || is_mac)
+import("//build/config/linux/pkg_config.gni")
+import("//build/shim_headers.gni")
 
-import("//build/config/features.gni")
-
-config("libusb_config") {
-  include_dirs = [ "src/libusb" ]
+pkg_config("system_libusb") {
+  packages = [ "libusb-1.0" ]
 }
 
-config("libusb_linker_config") {
-  if (is_win) {
-    ldflags = [
-      "/DELAYLOAD:advapi32.dll",
-      "/DELAYLOAD:cfgmgr32.dll",
-      "/DELAYLOAD:ole32.dll",
-      "/DELAYLOAD:setupapi.dll",
-      "/DELAYLOAD:winusb.dll",
-    ]
-  }
+shim_headers("libusb_shim") {
+  root_path = "src/libusb"
+  headers = [
+    "libusb.h",
+  ]
 }
 
-config("libusb_warnings") {
-  visibility = [ ":*" ]
-  if (is_clang) {
-    # guid_eq in windows_usb.c is unused.
-    cflags = [ "-Wno-unused-function" ]
-    if (is_linux && !use_udev) {
-      cflags += [ "-Wno-pointer-sign" ]
-    }
-  }
-}
-
-static_library("libusb") {
-  visibility = [
-    "//services/device:tests",
-    "//services/device/usb",
+source_set("libusb") {
+  deps = [
+    ":libusb_shim",
   ]
-  sources = [
-    "src/config.h",
-    "src/libusb/core.c",
-    "src/libusb/descriptor.c",
-    "src/libusb/hotplug.c",
-    "src/libusb/hotplug.h",
-    "src/libusb/interrupt.c",
-    "src/libusb/interrupt.h",
-    "src/libusb/io.c",
-    "src/libusb/libusb.h",
-    "src/libusb/libusbi.h",
-    "src/libusb/os/darwin_usb.c",
-    "src/libusb/os/darwin_usb.h",
-    "src/libusb/os/poll_posix.c",
-    "src/libusb/os/poll_posix.h",
-    "src/libusb/os/poll_windows.c",
-    "src/libusb/os/poll_windows.h",
-    "src/libusb/os/threads_posix.c",
-    "src/libusb/os/threads_posix.h",
-    "src/libusb/os/threads_windows.c",
-    "src/libusb/os/threads_windows.h",
-    "src/libusb/os/windows_common.h",
-    "src/libusb/os/windows_usb.c",
-    "src/libusb/os/windows_usb.h",
-    "src/libusb/strerror.c",
-    "src/libusb/sync.c",
-    "src/libusb/version.h",
-    "src/libusb/version_nano.h",
-    "src/msvc/config.h",
-    "src/msvc/inttypes.h",
-    "src/msvc/stdint.h",
-  ]
-  deps = []
-  include_dirs = [ "src/libusb/os" ]
-
-  configs -= [ "//build/config/compiler:chromium_code" ]
-  configs += [
-    "//build/config/compiler:no_chromium_code",
-
-    # Must be after no_chromium_code for warning flags to be ordered correctly.
-    ":libusb_warnings",
-  ]
-
-  public_configs = [ ":libusb_config" ]
-  all_dependent_configs = [ ":libusb_linker_config" ]
-
-  if (is_posix) {
-    defines = [
-      "DEFAULT_VISIBILITY=",
-      "HAVE_GETTIMEOFDAY=1",
-      "HAVE_POLL_H=1",
-      "HAVE_SYS_TIME_H=1",
-      "LIBUSB_DESCRIBE=\"1.0.16\"",
-      "POLL_NFDS_TYPE=nfds_t",
-      "THREADS_POSIX=1",
-    ]
-  }
-
-  if (is_mac) {
-    defines += [
-      "OS_DARWIN=1",
-
-      # Needed on OSX 10.12 to silence a deprecation warning.
-      "OBJC_SILENCE_GC_DEPRECATIONS=1",
-    ]
-    libs = [
-      "CoreFoundation.framework",
-      "IOKit.framework",
-    ]
-  } else {
-    sources -= [
-      "src/libusb/os/darwin_usb.c",
-      "src/libusb/os/darwin_usb.h",
-    ]
-  }
-
-  if (is_linux) {
-    sources += [
-      "src/libusb/os/linux_usbfs.c",
-      "src/libusb/os/linux_usbfs.h",
-    ]
-    defines += [
-      "OS_LINUX=1",
-      "_GNU_SOURCE=1",
-    ]
-  }
-
-  if (is_chromeos) {
-    defines += [ "USBI_TIMERFD_AVAILABLE" ]
-  }
-
-  if (use_udev) {
-    sources += [ "src/libusb/os/linux_udev.cc" ]
-    defines += [
-      "HAVE_LIBUDEV=1",
-      "USE_UDEV=1",
-    ]
-    deps += [ "//build/linux/libudev" ]
-  }
-
-  if (is_linux && !use_udev) {
-    sources += [ "src/libusb/os/linux_netlink.c" ]
-    defines += [ "HAVE_LINUX_NETLINK_H" ]
-  }
-
-  if (is_win) {
-    include_dirs += [ "src/msvc" ]
-    sources -= [
-      "src/libusb/os/poll_posix.c",
-      "src/libusb/os/threads_posix.c",
-    ]
-    libs = [
-      "advapi32.lib",
-      "ole32.lib",
-      "setupapi.lib",
-      "winusb.lib",
-    ]
-  } else {
-    include_dirs += [ "src" ]
-    sources -= [
-      "src/libusb/os/poll_windows.c",
-      "src/libusb/os/poll_windows.h",
-      "src/libusb/os/threads_windows.c",
-      "src/libusb/os/threads_windows.h",
-      "src/libusb/os/windows_common.h",
-      "src/libusb/os/windows_usb.c",
-      "src/libusb/os/windows_usb.h",
-      "src/msvc/config.h",
-      "src/msvc/inttypes.h",
-      "src/msvc/stdint.h",
-    ]
-  }
+  public_configs = [ ":system_libusb" ]
 }