obs-studio/cmake/Modules/FindThreads.cmake

203 lines
6.3 KiB
CMake

#.rst:
# FindThreads
# -----------
#
# This module determines the thread library of the system.
#
# The following import target is created
#
# ::
#
# CMake::Threads
#
# The following variables are set
#
# ::
#
# THREADS_FOUND
# THREADS_LIBRARIES
# THREADS_DEFINITIONS
#
# Legacy variables
#
# ::
#
# CMAKE_THREAD_LIBS_INIT - the thread library
# CMAKE_THREAD_DEFS_INIT - the thread compile definitions
# CMAKE_USE_SPROC_INIT - are we using sproc?
# CMAKE_USE_WIN32_THREADS_INIT - using WIN32 threads?
# CMAKE_USE_PTHREADS_INIT - are we using pthreads
# CMAKE_HP_PTHREADS_INIT - are we using hp pthreads
#
# For systems with multiple thread libraries, caller can set
#
# ::
#
# CMAKE_THREAD_PREFER_PTHREAD
#=============================================================================
# Copyright 2002-2014 Kitware, Inc.
#
# Distributed under the OSI-approved BSD License (the "License");
# see accompanying file Copyright.txt for details.
#
# This software is distributed WITHOUT ANY WARRANTY; without even the
# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
# See the License for more information.
#=============================================================================
# (To distribute this file outside of CMake, substitute the full
# License text for the above reference.)
include(CheckIncludeFiles)
include(CheckLibraryExists)
include(CheckSymbolExists)
set(Threads_FOUND FALSE)
set(CMAKE_REQUIRED_QUIET_SAVE ${CMAKE_REQUIRED_QUIET})
set(CMAKE_REQUIRED_QUIET ${Threads_FIND_QUIETLY})
# Do we have sproc?
if(CMAKE_SYSTEM_NAME MATCHES IRIX AND NOT CMAKE_THREAD_PREFER_PTHREAD)
check_include_files("sys/types.h;sys/prctl.h" CMAKE_HAVE_SPROC_H)
endif()
if(CMAKE_HAVE_SPROC_H AND NOT CMAKE_THREAD_PREFER_PTHREAD)
# We have sproc
set(CMAKE_USE_SPROC_INIT 1)
else()
# Do we have pthreads?
check_include_files("pthread.h" CMAKE_HAVE_PTHREAD_H)
if(CMAKE_HAVE_PTHREAD_H)
#
# We have pthread.h
# Let's check for the library now.
#
set(CMAKE_HAVE_THREADS_LIBRARY)
# Check if pthread functions are in normal C library
check_symbol_exists(pthread_create pthread.h CMAKE_HAVE_LIBC_CREATE)
if(CMAKE_HAVE_LIBC_CREATE)
set(CMAKE_THREAD_LIBS_INIT "")
set(CMAKE_HAVE_THREADS_LIBRARY 1)
set(Threads_FOUND TRUE)
endif()
if(NOT Threads_FOUND AND NOT THREADS_HAVE_PTHREAD_ARG)
message(STATUS "Check if compiler accepts -pthread")
try_run(THREADS_PTHREAD_ARG THREADS_HAVE_PTHREAD_ARG
${CMAKE_BINARY_DIR}
${CMAKE_CURRENT_LIST_DIR}/CheckForPthreads.c
COMPILE_DEFINITIONS -pthread
CMAKE_FLAGS -DLINK_LIBRARIES:STRING=-pthread
COMPILE_OUTPUT_VARIABLE OUTPUT)
if(THREADS_HAVE_PTHREAD_ARG)
if(THREADS_PTHREAD_ARG STREQUAL "2")
message(STATUS "Check if compiler accepts -pthread - yes")
else()
message(STATUS "Check if compiler accepts -pthread - no")
file(APPEND
${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
"Determining if compiler accepts -pthread returned ${THREADS_PTHREAD_ARG} instead of 2. The compiler had the following output:\n${OUTPUT}\n\n")
set(THREADS_HAVE_PTHREAD_ARG)
endif()
else()
message(STATUS "Check if compiler accepts -pthread - no")
file(APPEND
${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
"Determining if compiler accepts -pthread failed with the following output:\n${OUTPUT}\n\n")
endif()
endif()
if(NOT Threads_FOUND AND THREADS_HAVE_PTHREAD_ARG)
set(Threads_FOUND TRUE)
set(CMAKE_THREAD_LIBS_INIT "-pthread")
set(CMAKE_THREAD_DEFS_INIT "-pthread")
endif()
if(NOT Threads_FOUND)
if(NOT CMAKE_HAVE_THREADS_LIBRARY)
# Do we have -lpthreads
check_library_exists(pthreads pthread_create "" CMAKE_HAVE_PTHREADS_CREATE)
if(CMAKE_HAVE_PTHREADS_CREATE)
set(CMAKE_THREAD_LIBS_INIT "-lpthreads")
set(CMAKE_HAVE_THREADS_LIBRARY 1)
set(Threads_FOUND TRUE)
endif()
# Ok, how about -lpthread
check_library_exists(pthread pthread_create "" CMAKE_HAVE_PTHREAD_CREATE)
if(CMAKE_HAVE_PTHREAD_CREATE)
set(CMAKE_THREAD_LIBS_INIT "-lpthread")
set(CMAKE_HAVE_THREADS_LIBRARY 1)
set(Threads_FOUND TRUE)
endif()
if(CMAKE_SYSTEM MATCHES "SunOS.*")
# On sun also check for -lthread
check_library_exists(thread thr_create "" CMAKE_HAVE_THR_CREATE)
if(CMAKE_HAVE_THR_CREATE)
set(CMAKE_THREAD_LIBS_INIT "-lthread")
set(CMAKE_HAVE_THREADS_LIBRARY 1)
set(Threads_FOUND TRUE)
endif()
endif()
endif()
endif()
endif()
endif()
if(CMAKE_THREAD_LIBS_INIT OR CMAKE_HAVE_LIBC_CREATE)
set(CMAKE_USE_PTHREADS_INIT 1)
set(Threads_FOUND TRUE)
endif()
if(CMAKE_SYSTEM_NAME MATCHES "Windows")
set(CMAKE_USE_WIN32_THREADS_INIT 1)
set(Threads_FOUND TRUE)
endif()
if(CMAKE_USE_PTHREADS_INIT)
if(CMAKE_SYSTEM_NAME MATCHES "HP-UX")
# Use libcma if it exists and can be used. It provides more
# symbols than the plain pthread library. CMA threads
# have actually been deprecated:
# http://docs.hp.com/en/B3920-90091/ch12s03.html#d0e11395
# http://docs.hp.com/en/947/d8.html
# but we need to maintain compatibility here.
# The CMAKE_HP_PTHREADS setting actually indicates whether CMA threads
# are available.
check_library_exists(cma pthread_attr_create "" CMAKE_HAVE_HP_CMA)
if(CMAKE_HAVE_HP_CMA)
set(CMAKE_THREAD_LIBS_INIT "-lcma")
set(CMAKE_HP_PTHREADS_INIT 1)
set(Threads_FOUND TRUE)
endif()
set(CMAKE_USE_PTHREADS_INIT 1)
endif()
if(CMAKE_SYSTEM MATCHES "OSF1-V")
set(CMAKE_USE_PTHREADS_INIT 0)
set(CMAKE_THREAD_LIBS_INIT )
endif()
if(CMAKE_SYSTEM MATCHES "CYGWIN_NT")
set(CMAKE_USE_PTHREADS_INIT 1)
set(Threads_FOUND TRUE)
set(CMAKE_THREAD_LIBS_INIT )
set(CMAKE_USE_WIN32_THREADS_INIT 0)
endif()
endif()
set(CMAKE_REQUIRED_QUIET ${CMAKE_REQUIRED_QUIET_SAVE})
include(FindPackageHandleStandardArgs)
find_package_handle_standard_args(Threads DEFAULT_MSG Threads_FOUND)
if(THREADS_FOUND)
set(THREADS_LIBRARIES "${CMAKE_THREAD_LIBS_INIT}")
set(THREADS_DEFINITIONS "${CMAKE_THREAD_DEFS_INIT}")
endif()