Introduce modern way to link with pthread library

CMakeLists.txt

@@ -382,40 +382,15 @@ if(WIN32)
   endif()
 endif()
 
-# Add library ws2_32.a or ws2_32.lib for vpNetwork class
 if(WIN32 AND NOT CYGWIN)
-  if(MINGW)
-    set(WS2_32_LIBRARY "ws2_32.a")
-    check_library_exists(${WS2_32_LIBRARY} getch "" HAVE_LIBWS2_32) # for inet_ntoa() and socket functionalities
-    if(HAVE_LIBWS2_32)
-      list(APPEND VISP_LINKER_LIBS ${WS2_32_LIBRARY})
-    else()
-      find_library(HAVE_LIBWS2_32 ${WS2_32_LIBRARY}
-        "$ENV{MINGW_DIR}/lib"
-        "$ENV{MINGW_DIR}/mingw/lib"
-        C:/mingw/mingw/lib)
-      if(HAVE_LIBWS2_32)
-        list(APPEND VISP_LINKER_LIBS "${WS2_32_LIBRARY}")
-      endif()
-    endif()
-  elseif(WINRT)
-    # Since check_library_exists() and find_library() does't work to detect ws2_32.lib we add the lib that is part of Windows SDK
-    set(WS2_32_LIBRARY "ws2_32.lib")
-    list(APPEND VISP_LINKER_LIBS  ${WS2_32_LIBRARY})
-  else() # pure WIN32
-    set(WS2_32_LIBRARY "ws2_32.lib")
-    #check_library_exists("ws2_32.lib" getch "" HAVE_LIBWS2_32) # for inet_ntoa() and socket functionalities
-    check_library_exists(${WS2_32_LIBRARY} getch "" HAVE_LIBWS2_32) # for inet_ntoa() and socket functionalities
-    if(HAVE_LIBWS2_32)
-      list(APPEND VISP_LINKER_LIBS ${WS2_32_LIBRARY})
-    endif()
-  endif()
-  mark_as_advanced(HAVE_LIBWS2_32)
+  VP_CHECK_PACKAGE(WS2_32)
+  # Should be before include(cmake/VISPDetectCXXStandard.cmake)
+  VP_CHECK_FUNCTION_EXISTS(inet_ntop "${WS2_32_LIBRARY}")
+else()
+  # Should be before include(cmake/VISPDetectCXXStandard.cmake)
+  VP_CHECK_FUNCTION_EXISTS(inet_ntop "")
 endif()
 
-# Should be before include(cmake/VISPDetectCXXStandard.cmake)
-VP_CHECK_FUNCTION_EXISTS(inet_ntop "${VISP_LINKER_LIBS}")
-
 #--------------------------------------------------------------------
 # Option management
 #--------------------------------------------------------------------
@@ -571,19 +546,18 @@ if(SOQT_FOUND) # SoQt < 1.6.0 that depends on Qt4 was found. We need an explicit
   VP_OPTION(USE_QT        Qt          ""    "Include Coin/SoQt/Qt support" "" ON  IF USE_SOQT AND NOT WINRT AND NOT IOS)
 endif()
 VP_OPTION(USE_SOXT        SOXT        ""    "Include Coin/SoXt support"    "" OFF IF USE_COIN3D AND NOT WINRT AND NOT IOS)
-if (ANDROID)
-  VP_OPTION(USE_PTHREAD     Threads     ""    "Include pthread support"      "" ON)
-else()
-  VP_OPTION(USE_PTHREAD     PTHREAD     ""    "Include pthread support"      "" ON)
-endif()
+set(THREADS_PREFER_PTHREAD_FLAG ON)
+VP_OPTION(USE_PTHREAD     Threads     ""    "Include pthread support"      "" ON IF NOT (WIN32 OR MINGW))
+
 # We need threads with c++11
 if((VISP_CXX_STANDARD GREATER VISP_CXX_STANDARD_98) AND NOT USE_PTHREAD)
-  if(Threads_FOUND OR PTHREAD_FOUND)
+  if(Threads_FOUND)
     message(WARNING "We need threads. Turn USE_PTHREAD=ON.")
     unset(USE_PTHREAD)
     set(USE_PTHREAD ON CACHE BOOL "Include pthread support" FORCE)
   endif()
 endif()
+
 VP_OPTION(USE_XML2        XML2        ""    "Include xml support"          "" ON IF NOT WINRT)
 if(CMAKE_TOOLCHAIN_FILE)
   # Find opencv2.framework for ios and naoqi

cmake/AddExtraCompilationFlags.cmake

@@ -113,6 +113,12 @@ if(USE_OPENMP)
   add_extra_compiler_option("${OpenMP_CXX_FLAGS}")
 endif()
 
+if(USE_PTHREAD)
+  if(THREADS_HAVE_PTHREAD_ARG)
+    add_extra_compiler_option("-pthread")
+  endif()
+endif()
+
 if((VISP_CXX_STANDARD EQUAL VISP_CXX_STANDARD_11) AND CXX11_CXX_FLAGS)
   add_extra_compiler_option("${CXX11_CXX_FLAGS}")
 elseif((VISP_CXX_STANDARD EQUAL VISP_CXX_STANDARD_14) AND CXX14_CXX_FLAGS)

cmake/FindWS2_32.cmake

@@ -0,0 +1,76 @@
+#############################################################################
+#
+# ViSP, open source Visual Servoing Platform software.
+# Copyright (C) 2005 - 2023 by Inria. All rights reserved.
+#
+# This software is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+# See the file LICENSE.txt at the root directory of this source
+# distribution for additional information about the GNU GPL.
+#
+# For using ViSP with software that can not be combined with the GNU
+# GPL, please contact Inria about acquiring a ViSP Professional
+# Edition License.
+#
+# See https://visp.inria.fr for more information.
+#
+# This software was developed at:
+# Inria Rennes - Bretagne Atlantique
+# Campus Universitaire de Beaulieu
+# 35042 Rennes Cedex
+# France
+#
+# If you have questions regarding the use of this file, please contact
+# Inria at [email protected]
+#
+# This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+# WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+#
+# Description:
+# Try to find ws2_32 library.
+#
+# WS2_32_FOUND - true if ws2_32 library is detected
+# WS2_32_LIBRARY - Library name
+#
+#############################################################################
+
+if(WIN32 AND NOT CYGWIN)
+  if(MINGW)
+    set(WS2_32_LIBNAME "ws2_32.a")
+    check_library_exists(${WS2_32_LIBNAME} getch "" HAVE_LIBWS2_32) # for inet_ntoa() and socket functionalities
+    if(HAVE_LIBWS2_32)
+      set(WS2_32_LIBRARY ${WS2_32_LIBNAME})
+      set(WS2_32_FOUND TRUE)
+    else()
+      find_library(HAVE_LIBWS2_32 ${WS2_32_LIBNAME}
+        "$ENV{MINGW_DIR}/lib"
+        "$ENV{MINGW_DIR}/mingw/lib"
+        C:/mingw/mingw/lib)
+      if(HAVE_LIBWS2_32)
+        set(WS2_32_LIBRARY ${WS2_32_LIBNAME})
+        set(WS2_32_FOUND TRUE)
+      else()
+        set(WS2_32_FOUND FALSE)
+      endif()
+    endif()
+  elseif(WINRT)
+    # Since check_library_exists() and find_library() does't work to detect ws2_32.lib we add the lib that is part of Windows SDK
+    set(WS2_32_LIBNAME "ws2_32.lib")
+    set(WS2_32_LIBRARY ${WS2_32_LIBNAME})
+    set(WS2_32_FOUND TRUE)
+  else() # pure WIN32
+    set(WS2_32_LIBNAME "ws2_32.lib")
+    check_library_exists(${WS2_32_LIBNAME} getch "" HAVE_LIBWS2_32) # for inet_ntoa() and socket functionalities
+    if(HAVE_LIBWS2_32)
+      message("-----------> ${WS2_32_LIBNAME} is found")
+      set(WS2_32_LIBRARY ${WS2_32_LIBNAME})
+      set(WS2_32_FOUND TRUE)
+    else()
+      set(WS2_32_FOUND FALSE)
+    endif()
+  endif()
+  mark_as_advanced(WS2_32_LIBNAME)
+  mark_as_advanced(HAVE_LIBWS2_32)
+endif()

cmake/VISPModule.cmake

@@ -785,7 +785,7 @@ endmacro()
 # creates ViSP module in current folder
 # creates new target, configures standard dependencies, compilers flags, install rules
 # Usage:
-#   vp_create_module(<extra link dependencies> LINK_PRIVATE <private link dependencies>)
+#   vp_create_module(<extra link dependencies>)
 #   vp_create_module()
 macro(vp_create_module)
   vp_debug_message("vp_create_module(" ${ARGN} ")")
@@ -801,11 +801,11 @@ macro(_vp_create_module)
   vp_add_library(${the_module} ${VISP_MODULE_TYPE} ${VISP_MODULE_${the_module}_HEADERS} ${VISP_MODULE_${the_module}_SOURCES})
 
   vp_target_link_libraries(${the_module}
-    LINK_PUBLIC
+    PUBLIC
       ${VISP_MODULE_${the_module}_DEPS_TO_LINK}
       ${VISP_MODULE_${the_module}_DEPS_EXT}
       ${VISP_MODULE_${the_module}_LINK_DEPS}
-    LINK_PRIVATE
+    PRIVATE
       ${VISP_MODULE_${the_module}_PRIVATE_REQ_DEPS}
       ${VISP_MODULE_${the_module}_PRIVATE_OPT_DEPS}
       ${VISP_LINKER_LIBS})
@@ -1016,7 +1016,7 @@ macro(vp_add_tests)
           # From source compile the binary and add link rules
           vp_add_executable(${the_target} ${t})
           vp_target_include_modules(${the_target} ${test_deps})
-          vp_target_link_libraries(${the_target} ${test_deps} ${VISP_MODULE_${the_module}_DEPS} ${VISP_LINKER_LIBS})
+          vp_target_link_libraries(${the_target} ${test_deps} ${VISP_MODULE_${the_module}_DEPS}) # should be removed ? ${VISP_LINKER_LIBS})
 
           # ctest only:
           # - if required dataset available

cmake/VISPUtils.cmake

@@ -855,6 +855,7 @@ macro(VP_CHECK_FUNCTION_EXISTS function libraries)
   string(TOUPPER "${ALIAS}" ALIAS_UPPER)
   set(ALIAS_HAVE            HAVE_FUNC_${ALIAS_UPPER})
   set(CMAKE_REQUIRED_LIBRARIES "${libraries}")
+  message("  -------> CMAKE_REQUIRED_LIBRARIES: ${CMAKE_REQUIRED_LIBRARIES}")
   check_function_exists(${ALIAS} ${ALIAS_HAVE})
 endmacro()
 
@@ -1645,7 +1646,7 @@ macro(vp_get_all_libs _modules _extra_opt _extra_dbg _3rdparty)
       endif()
     endforeach()
 
-    foreach (dep ${deps} ${VISP_LINKER_LIBS})
+    foreach (dep ${deps}) # Should be remove ? ${VISP_LINKER_LIBS})
       if (NOT DEFINED VISP_MODULE_${dep}_LOCATION)
         if(dep MATCHES "^\\$<LINK_ONLY:([^>]+)>$")
           set(dep_dbg "${CMAKE_MATCH_1}")

modules/core/CMakeLists.txt

@@ -39,6 +39,11 @@
 set(opt_incs "")
 set(opt_libs "")
 
+# Add library ws2_32.a or ws2_32.lib for vpNetwork class
+if(WS2_32_FOUND)
+  list(APPEND opt_libs ${WS2_32_LIBRARY})
+endif()
+
 # OpenCV
 if(USE_OPENCV)
   # On win32 since OpenCV 2.4.7 and on OSX with OpenCV 2.4.10 we cannot use OpenCV_LIBS to set ViSP 3rd party libraries.
@@ -222,16 +227,29 @@ if(USE_XML2)
   list(APPEND opt_libs ${XML2_LIBRARIES})
 endif()
 if(USE_PTHREAD)
-  list(APPEND opt_incs ${PTHREAD_INCLUDE_DIRS})
-  list(APPEND opt_libs ${PTHREAD_LIBRARIES})
+  if(CMAKE_THREAD_LIBS_INIT)
+    list(APPEND opt_libs "${CMAKE_THREAD_LIBS_INIT}")
+  endif()
 endif()
 if(USE_ZLIB)
   list(APPEND opt_incs ${ZLIB_INCLUDE_DIRS})
   list(APPEND opt_libs ${ZLIB_LIBRARIES})
 endif()
 if(USE_OPENMP)
   list(APPEND opt_incs ${OpenMP_CXX_INCLUDE_DIRS})
-  list(APPEND opt_libs ${OpenMP_CXX_LIBRARIES})
+  # Because there is an explicit link to libpthread location that breaks visp conda package usage on linux
+  # we cannot use OpenMP_CXX_LIBRARIES that contains /usr/lib/gcc/x86_64-linux-gnu/11/libgomp.so;/usr/lib/x86_64-linux-gnu/libpthread.a
+  # by adding:
+  # list(APPEND opt_libs ${OpenMP_CXX_LIBRARIES})
+  foreach(lib_ ${OpenMP_CXX_LIB_NAMES})
+    if("x${lib_}" STREQUAL "xpthread")
+      if(CMAKE_THREAD_LIBS_INIT)
+        list(APPEND opt_libs "${CMAKE_THREAD_LIBS_INIT}")
+      endif()
+    else()
+      list(APPEND opt_libs ${OpenMP_${lib_}_LIBRARY})
+    endif()
+  endforeach()
 endif()
 if(USE_NLOHMANN_JSON)
   get_target_property(_inc_dirs "nlohmann_json::nlohmann_json" INTERFACE_INCLUDE_DIRECTORIES)

modules/core/include/visp3/core/vpImageCircle.h

@@ -48,7 +48,7 @@
 #include <visp3/core/vpRect.h>
 
 #if defined(VISP_HAVE_OPENCV)
-#include <opencv2/core.hpp>
+#include <opencv2/core/core.hpp>
 #endif
 
 /**