try to fix thread detection

Author: mpromonet

CMakeLists.txt

@@ -41,7 +41,6 @@ find_package(Git)
 # webrtc build
 set (WEBRTCBUILD ${WEBRTCROOT}/src/out/${CMAKE_BUILD_TYPE})
 set (WEBRTCOBJS ${WEBRTCBUILD}/obj)
-
 if (NOT EXISTS ${WEBRTCOBJS}/${CMAKE_STATIC_LIBRARY_PREFIX}webrtc${CMAKE_STATIC_LIBRARY_SUFFIX})
   if(GIT_FOUND)
     EXECUTE_PROCESS(WORKING_DIRECTORY ${WEBRTCROOT}/src COMMAND ${GIT_EXECUTABLE} status)
@@ -269,6 +268,9 @@ target_include_directories(${CMAKE_PROJECT_NAME} PRIVATE cxxopts/include)
 target_compile_definitions(${CMAKE_PROJECT_NAME} PRIVATE CXXOPTS_NO_RTTI)
 
 # thread
+if (NOT WIN32)
+  set(CMAKE_THREAD_LIBS_INIT "-lpthread")
+endif()
 set(CMAKE_THREAD_PREFER_PTHREAD TRUE)
 set(THREADS_PREFER_PTHREAD_FLAG TRUE)
 find_package (Threads)
@@ -370,12 +372,12 @@ target_include_directories(civetweb PUBLIC civetweb/include)
 find_package(PkgConfig QUIET)
 pkg_check_modules(RTMP QUIET librtmp)
 MESSAGE("RTMP_FOUND = ${RTMP_FOUND} RTMP_INCLUDE_DIRS=${RTMP_INCLUDE_DIRS} RTMP_LIBRARY_DIRS=${RTMP_LIBRARY_DIRS} RTMP_LIBRARIES=${RTMP_LIBRARIES}")
-if (RTMP_FOUND)
+find_library(RTMP_LIB QUIET rtmp)
+MESSAGE("RTMP_LIB=${RTMP_LIB}")
+if (RTMP_FOUND AND RTMP_LIB_FOUND)
   target_compile_definitions(${CMAKE_PROJECT_NAME} PRIVATE HAVE_RTMP)
   target_include_directories(${CMAKE_PROJECT_NAME} PUBLIC ${RTMP_INCLUDE_DIRS})
   target_link_directories(${CMAKE_PROJECT_NAME} PUBLIC ${RTMP_LIBRARY_DIRS})
-  find_library(RTMP_LIB rtmp)
-  MESSAGE("RTMP_LIB=${RTMP_LIB}")
   target_link_libraries (${CMAKE_PROJECT_NAME} ${RTMP_LIB})
 endif()