Add include guards

CMakeModules/FindDepotTools.cmake

@@ -1,3 +1,8 @@
+if(FIND_DEPOT_TOOLS_INCLUDED)
+  return()
+endif(FIND_DEPOT_TOOLS_INCLUDED)
+set(FIND_DEPOT_TOOLS_INCLUDED true)
+
 find_program(GCLIENT_EXECUTABLE
              NAMES gclient gclient.bat
              DOC "Path to gclient executable"

CMakeModules/FindLibraries.cmake

@@ -1,3 +1,8 @@
+if(FIND_LIBRARIES_INCLUDED)
+  return()
+endif(FIND_LIBRARIES_INCLUDED)
+set(FIND_LIBRARIES_INCLUDED true)
+
 #
 # Find required packages
 list(APPEND LIBWEBRTC_LIBRARIES webrtc)

CMakeModules/GClientConfig.cmake

@@ -1,3 +1,8 @@
+if(GCLIENT_CONFIG_INCLUDED)
+  return()
+endif(GCLIENT_CONFIG_INCLUDED)
+set(GCLIENT_CONFIG_INCLUDED true)
+
 #
 # Retrieve WebRTC source code
 #
@@ -22,4 +27,4 @@ elseif (TARGET_OS STREQUAL "mac")
   file(APPEND ${CMAKE_BINARY_DIR}/.gclient "target_os = [\"mac\"]")
 elseif (TARGET_OS STREQUAL "win")
   file(APPEND ${CMAKE_BINARY_DIR}/.gclient "target_os = [\"win\"]")
-endif (TARGET_OS STREQUAL "android")
+endif (TARGET_OS STREQUAL "android")

CMakeModules/Install.cmake

@@ -1,3 +1,8 @@
+if(INSTALL_INCLUDED)
+  return()
+endif(INSTALL_INCLUDED)
+set(INSTALL_INCLUDED true)
+
 #
 # Install library
 file(GLOB_RECURSE _LIBRARY_FILES

CMakeModules/LibWebRTCCommand.cmake

@@ -1,3 +1,8 @@
+if(LIBWEBRTC_COMMAND_INCLUDED)
+  return()
+endif(LIBWEBRTC_COMMAND_INCLUDED)
+set(LIBWEBRTC_COMMAND_INCLUDED true)
+
 include(CMakeParseArguments)
 include(Prefix)
 

CMakeModules/Options.cmake

@@ -1,3 +1,8 @@
+if(OPTIONS_INCLUDED)
+  return()
+endif(OPTIONS_INCLUDED)
+set(OPTIONS_INCLUDED true)
+
 #
 # Options, flags
 option(BUILD_TESTS "Build test binaries" OFF)

CMakeModules/Package.cmake

@@ -1,3 +1,8 @@
+if(PACKAGE_INCLUDED)
+  return()
+endif(PACKAGE_INCLUDED)
+set(PACKAGE_INCLUDED true)
+
 #
 # Create package
 set(CPACK_PACKAGE_FILE_NAME "libwebrtc-${LIBWEBRTC_VERSION}-${TARGET_OS}-${TARGET_CPU}")

CMakeModules/Prefix.cmake

@@ -1,3 +1,8 @@
+if(PREFIX_INCLUDED)
+  return()
+endif(PREFIX_INCLUDED)
+set(PREFIX_INCLUDED true)
+
 #
 # Generate environment variables
 #

CMakeModules/TargetOsAndCpu.cmake

@@ -1,3 +1,8 @@
+if(TARGET_OS_AND_CPU_INCLUDED)
+  return()
+endif(TARGET_OS_AND_CPU_INCLUDED)
+set(TARGET_OS_AND_CPU_INCLUDED true)
+
 include(CheckSymbolExists)
 
 #
@@ -82,4 +87,4 @@ elseif (WIN32)
   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)
+endif(UNIX)

CMakeModules/Version.cmake

@@ -1,3 +1,8 @@
+if(VERSION_INCLUDED)
+  return()
+endif(VERSION_INCLUDED)
+set(VERSION_INCLUDED true)
+
 #
 # Set the project's version