CMake: Allow specifying an optional host tools path for doc generation

Introduce a new QT_OPTIONAL_TOOLS_PATH cmake variable that can be set
to a path where some of the documentation generation host tools might
be located.

This allows using specific builds of qdoc, qvkgen, qdbusxml2cpp and
qtattributionsscanner for documentation generation.

QT_HOST_PATH wouldn't be sufficient in this case, because it requires
all host tools to be installed for the given path, otherwise
configuration will fail

In contrast with QT_OPTIONAL_TOOLS_PATH we can specify the paths only
for the tools listed above, while continuing using other build tools
from the usual locations, either built or found.

As a drive-by, fix the usage of CMAKE_EXECUTABLE_SUFFIX to be based
on the host platform.

Pick-to: 6.8
Task-number: QTBUG-128730
Change-Id: I2796be3a9772b106788ce63a4aed890516e8b716
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>

Author: alcroito

cmake/QtDbusHelpers.cmake

@@ -55,10 +55,22 @@ function(qt_create_qdbusxml2cpp_command target infile)
     set(header_file_full "${CMAKE_CURRENT_BINARY_DIR}/${file_name}.h")
     set(source_file_full "${CMAKE_CURRENT_BINARY_DIR}/${file_name}.cpp")
 
+    if(QT_OPTIONAL_TOOLS_PATH)
+        if(CMAKE_HOST_WIN32)
+            set(executable_suffix ".exe")
+        else()
+            set(executable_suffix "")
+        endif()
+        set(tool_path
+            "${QT_OPTIONAL_TOOLS_PATH}/${INSTALL_BINDIR}/qdbusxml2cpp${executable_suffix}")
+    else()
+        set(tool_path "${QT_CMAKE_EXPORT_NAMESPACE}::qdbusxml2cpp")
+    endif()
+
     add_custom_command(OUTPUT "${header_file_full}" "${source_file_full}"
-                       COMMAND ${QT_CMAKE_EXPORT_NAMESPACE}::qdbusxml2cpp ${arg_FLAGS} "${option}"
+                       COMMAND ${tool_path} ${arg_FLAGS} "${option}"
                                "${header_file}:${source_file}" "${absolute_in_file_path}"
-                       DEPENDS "${absolute_in_file_path}" ${QT_CMAKE_EXPORT_NAMESPACE}::qdbusxml2cpp
+                       DEPENDS "${absolute_in_file_path}" ${tool_path}
                        WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}"
                        COMMAND_EXPAND_LISTS
                        VERBATIM)

cmake/QtDocsHelpers.cmake

@@ -68,6 +68,10 @@ function(qt_internal_add_docs)
         set(tool_dependencies_enabled FALSE)
         set(doc_tools_bin "${QT_HOST_PATH}/${QT${PROJECT_VERSION_MAJOR}_HOST_INFO_BINDIR}")
         set(doc_tools_libexec "${QT_HOST_PATH}/${QT${PROJECT_VERSION_MAJOR}_HOST_INFO_LIBEXECDIR}")
+    elseif(NOT "${QT_OPTIONAL_TOOLS_PATH}" STREQUAL "")
+        set(tool_dependencies_enabled FALSE)
+        set(doc_tools_bin "${QT_OPTIONAL_TOOLS_PATH}/${INSTALL_BINDIR}")
+        set(doc_tools_libexec "${QT_OPTIONAL_TOOLS_PATH}/${INSTALL_LIBEXECDIR}")
     elseif(QT_SUPERBUILD)
         set(doc_tools_bin "${QtBase_BINARY_DIR}/${INSTALL_BINDIR}")
         set(doc_tools_libexec "${QtBase_BINARY_DIR}/${INSTALL_LIBEXECDIR}")
@@ -76,9 +80,15 @@ function(qt_internal_add_docs)
         set(doc_tools_libexec "${QT_BUILD_INTERNALS_RELOCATABLE_INSTALL_PREFIX}/${INSTALL_LIBEXECDIR}")
     endif()
 
-    set(qdoc_bin "${doc_tools_bin}/qdoc${CMAKE_EXECUTABLE_SUFFIX}")
-    set(qtattributionsscanner_bin "${doc_tools_libexec}/qtattributionsscanner${CMAKE_EXECUTABLE_SUFFIX}")
-    set(qhelpgenerator_bin "${doc_tools_libexec}/qhelpgenerator${CMAKE_EXECUTABLE_SUFFIX}")
+    if(CMAKE_HOST_WIN32)
+        set(executable_suffix ".exe")
+    else()
+        set(executable_suffix "")
+    endif()
+
+    set(qdoc_bin "${doc_tools_bin}/qdoc${executable_suffix}")
+    set(qtattributionsscanner_bin "${doc_tools_libexec}/qtattributionsscanner${executable_suffix}")
+    set(qhelpgenerator_bin "${doc_tools_libexec}/qhelpgenerator${executable_suffix}")
 
     get_target_property(target_type ${target} TYPE)
     if (NOT target_type STREQUAL "INTERFACE_LIBRARY")

src/gui/CMakeLists.txt

@@ -957,6 +957,11 @@ if (QT_FEATURE_vulkan)
             "${QT_HOST_PATH}"
             "${QT${PROJECT_VERSION_MAJOR}_HOST_INFO_LIBEXECDIR}"
             "qvkgen${host_executable_suffix}")
+    elseif(QT_OPTIONAL_TOOLS_PATH)
+        qt_path_join(qvkgen
+            "${QT_OPTIONAL_TOOLS_PATH}"
+            "${INSTALL_LIBEXECDIR}"
+            "qvkgen${host_executable_suffix}")
     else()
         set(qvkgen "${QT_CMAKE_EXPORT_NAMESPACE}::qvkgen")
     endif()