From b334e9098a15d9d986d0cb04556e70fb415f9bf0 Mon Sep 17 00:00:00 2001
From: Axel Isouard <axel@isouard.fr>
Date: Mon, 6 Feb 2017 19:22:15 +0100
Subject: [PATCH] Move target OS and CPU detection code to a separate CMake
 module

---
 CMakeLists.txt                    | 74 +------------------------------
 CMakeModules/TargetOsAndCpu.cmake | 62 ++++++++++++++++++++++++++
 2 files changed, 63 insertions(+), 73 deletions(-)
 create mode 100644 CMakeModules/TargetOsAndCpu.cmake

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b58b052..fd51901 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -11,79 +11,7 @@ set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH}
 include(FindLibraries)
 include(Version)
 include(Options)
-
-#
-# Target OS
-set(TARGET_OS "" CACHE STRING "Target OS, used as --target_os argument")
-set(TARGET_OS_LIST android chromeos ios linux nacl mac win)
-
-if (TARGET_OS STREQUAL "")
-  if (CMAKE_SYSTEM_NAME MATCHES "Linux")
-    set(TARGET_OS "linux")
-  elseif (CMAKE_SYSTEM_NAME MATCHES "Darwin")
-    set(TARGET_OS "mac")
-  elseif (CMAKE_SYSTEM_NAME MATCHES "Windows")
-    set(TARGET_OS "win")
-  endif ()
-endif (TARGET_OS STREQUAL "")
-
-if (NOT ${TARGET_OS} IN_LIST TARGET_OS_LIST)
-  message(FATAL_ERROR "Unknown value '${TARGET_OS}' for variable TARGET_OS, options are: ${TARGET_OS_LIST}")
-endif (NOT ${TARGET_OS} IN_LIST TARGET_OS_LIST)
-
-#
-# Target CPU
-set(TARGET_CPU "" CACHE STRING "Target CPU, used as --target_cpu argument")
-set(TARGET_CPU_LIST x86 x64 arm arm64 mipsel)
-
-if (TARGET_CPU STREQUAL "")
-  include(CheckSymbolExists)
-  if (WIN32)
-    check_symbol_exists("_M_X64" "" ARCH_X64)
-    if (NOT ARCH_X64)
-      check_symbol_exists("_M_AMD64" "" ARCH_X64)
-	  if (NOT ARCH_X64)
-        check_symbol_exists("_M_IX86" "" ARCH_X86)
-	    if (NOT ARCH_X86)
-          check_symbol_exists("_M_ARM" "" ARCH_ARM)
-          check_symbol_exists("_M_ARM64" "" ARCH_ARM64)
-        endif (NOT ARCH_X86)
-      endif (NOT ARCH_X64)
-    endif (NOT ARCH_X64)
-  else (WIN32)
-    check_symbol_exists("__i386__" "" ARCH_X86)
-    check_symbol_exists("__x86_64__" "" ARCH_X64)
-    check_symbol_exists("__arm__" "" ARCH_ARM)
-    check_symbol_exists("__aarch64__" "" ARCH_ARM64)
-  endif (WIN32)
-  if (ARCH_X86)
-    set(TARGET_CPU "x86")
-  elseif (ARCH_X64)
-    set(TARGET_CPU "x64")
-  else ()
-    set(TARGET_CPU ${CMAKE_SYSTEM_PROCESSOR})
-  endif (ARCH_X86)
-endif (TARGET_CPU STREQUAL "")
-
-if (NOT ${TARGET_CPU} IN_LIST TARGET_CPU_LIST)
-  message(FATAL_ERROR "Unknown value '${TARGET_CPU}' for variable TARGET_CPU, options are: ${TARGET_CPU_LIST}")
-endif (NOT ${TARGET_CPU} IN_LIST TARGET_CPU_LIST)
-
-if (UNIX)
-  if (ARCH_X86)
-    set(LIBWEBRTC_REQUIRED_CXX_FLAGS "-m32")
-  endif (ARCH_X86)
-  set(LIBWEBRTC_REQUIRED_CXX_FLAGS "${LIBWEBRTC_REQUIRED_CXX_FLAGS} -std=gnu++0x")
-  list(APPEND LIBWEBRTC_DEFINITIONS WEBRTC_POSIX _GLIBCXX_USE_CXX11_ABI=0)
-elseif (WIN32)
-  set(LIBWEBRTC_REQUIRED_C_FLAGS_DEBUG "/MTd")
-  set(LIBWEBRTC_REQUIRED_C_FLAGS_RELEASE "/MT")
-  set(LIBWEBRTC_REQUIRED_CXX_FLAGS_DEBUG "/MTd")
-  set(LIBWEBRTC_REQUIRED_CXX_FLAGS_RELEASE "/MT")
-  list(APPEND LIBWEBRTC_DEFINITIONS WEBRTC_WIN NOMINMAX _CRT_SECURE_NO_WARNINGS)
-endif(UNIX)
-
-set(LIBWEBRTC_LIBRARIES webrtc)
+include(TargetOsAndCpu)
 
 add_subdirectory(Targets)
 export(PACKAGE LibWebRTC)
diff --git a/CMakeModules/TargetOsAndCpu.cmake b/CMakeModules/TargetOsAndCpu.cmake
new file mode 100644
index 0000000..5f80455
--- /dev/null
+++ b/CMakeModules/TargetOsAndCpu.cmake
@@ -0,0 +1,62 @@
+include(CheckSymbolExists)
+
+function(detect_current_arch)
+  if (WIN32)
+    check_symbol_exists("_M_X64" "" ARCH_X64)
+    if (NOT ARCH_X64)
+      check_symbol_exists("_M_AMD64" "" ARCH_X64)
+    endif (NOT ARCH_X64)
+    check_symbol_exists("_M_IX86" "" ARCH_X86)
+    check_symbol_exists("_M_ARM" "" ARCH_ARM)
+    check_symbol_exists("_M_ARM64" "" ARCH_ARM64)
+  else (WIN32)
+    check_symbol_exists("__i386__" "" ARCH_X86)
+    check_symbol_exists("__x86_64__" "" ARCH_X64)
+    check_symbol_exists("__arm__" "" ARCH_ARM)
+    check_symbol_exists("__aarch64__" "" ARCH_ARM64)
+    check_symbol_exists("__mips__" "" ARCH_MIPS)
+  endif (WIN32)
+endfunction(detect_current_arch)
+
+#
+# Target CPU
+set(TARGET_CPU "" CACHE STRING "Target CPU, used as --target_cpu argument")
+set(TARGET_CPU_LIST x86 x64 arm arm64 mipsel)
+
+if (TARGET_CPU STREQUAL "")
+  detect_current_arch()
+
+  if (ARCH_X64)
+    set(TARGET_CPU "x64")
+  elseif (ARCH_X86)
+    set(TARGET_CPU "x86")
+  elseif (ARCH_ARM64)
+    set(TARGET_CPU "arm64")
+  elseif (ARCH_ARM)
+    set(TARGET_CPU "arm")
+  elseif (ARCH_MIPS)
+    set(TARGET_CPU "mipsel")
+  else ()
+    set(TARGET_CPU ${CMAKE_SYSTEM_PROCESSOR})
+  endif (ARCH_X64)
+endif (TARGET_CPU STREQUAL "")
+
+if (NOT ${TARGET_CPU} IN_LIST TARGET_CPU_LIST)
+  message(FATAL_ERROR "Unknown value '${TARGET_CPU}' for variable TARGET_CPU, options are: ${TARGET_CPU_LIST}")
+endif (NOT ${TARGET_CPU} IN_LIST TARGET_CPU_LIST)
+
+if (UNIX)
+  if (ARCH_X86)
+    set(LIBWEBRTC_REQUIRED_CXX_FLAGS "-m32")
+  endif (ARCH_X86)
+
+  set(LIBWEBRTC_REQUIRED_CXX_FLAGS "${LIBWEBRTC_REQUIRED_CXX_FLAGS} -std=gnu++0x")
+  list(APPEND LIBWEBRTC_DEFINITIONS
+       WEBRTC_POSIX _GLIBCXX_USE_CXX11_ABI=0 _CRT_SECURE_NO_WARNINGS)
+elseif (WIN32)
+  set(LIBWEBRTC_REQUIRED_C_FLAGS_DEBUG "/MTd")
+  set(LIBWEBRTC_REQUIRED_C_FLAGS_RELEASE "/MT")
+  set(LIBWEBRTC_REQUIRED_CXX_FLAGS_DEBUG "/MTd")
+  set(LIBWEBRTC_REQUIRED_CXX_FLAGS_RELEASE "/MT")
+  list(APPEND LIBWEBRTC_DEFINITIONS WEBRTC_WIN NOMINMAX _CRT_SECURE_NO_WARNINGS)
+endif(UNIX)
\ No newline at end of file