cmake/Modules/FindQt.cmake

# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.

#.rst:
# FindQt
# ------
#
# Searches for all installed versions of Qt.
#
# This should only be used if your project can work with multiple
# versions of Qt.  If not, you should just directly use FindQt4 or
# FindQt3.  If multiple versions of Qt are found on the machine, then
# The user must set the option DESIRED_QT_VERSION to the version they
# want to use.  If only one version of qt is found on the machine, then
# the DESIRED_QT_VERSION is set to that version and the matching FindQt3
# or FindQt4 module is included.  Once the user sets DESIRED_QT_VERSION,
# then the FindQt3 or FindQt4 module is included.
#
# This module can only detect and switch between Qt versions 3 and 4. It
# cannot handle Qt5 or any later versions.
#
# ::
#
#   QT_REQUIRED if this is set to TRUE then if CMake can
#               not find Qt4 or Qt3 an error is raised
#               and a message is sent to the user.
#
#
#
# ::
#
#   DESIRED_QT_VERSION OPTION is created
#   QT4_INSTALLED is set to TRUE if qt4 is found.
#   QT3_INSTALLED is set to TRUE if qt3 is found.

# look for signs of qt3 installations
file(GLOB GLOB_TEMP_VAR /usr/lib*/qt-3*/bin/qmake /usr/lib*/qt3*/bin/qmake)
if(GLOB_TEMP_VAR)
  set(QT3_INSTALLED TRUE)
endif()
set(GLOB_TEMP_VAR)

file(GLOB GLOB_TEMP_VAR /usr/local/qt-x11-commercial-3*/bin/qmake)
if(GLOB_TEMP_VAR)
  set(QT3_INSTALLED TRUE)
endif()
set(GLOB_TEMP_VAR)

file(GLOB GLOB_TEMP_VAR /usr/local/lib/qt3/bin/qmake)
if(GLOB_TEMP_VAR)
  set(QT3_INSTALLED TRUE)
endif()
set(GLOB_TEMP_VAR)

# look for qt4 installations
file(GLOB GLOB_TEMP_VAR /usr/local/qt-x11-commercial-4*/bin/qmake)
if(GLOB_TEMP_VAR)
  set(QT4_INSTALLED TRUE)
endif()
set(GLOB_TEMP_VAR)

file(GLOB GLOB_TEMP_VAR /usr/local/Trolltech/Qt-4*/bin/qmake)
if(GLOB_TEMP_VAR)
  set(QT4_INSTALLED TRUE)
endif()
set(GLOB_TEMP_VAR)

file(GLOB GLOB_TEMP_VAR /usr/local/lib/qt4/bin/qmake)
if(GLOB_TEMP_VAR)
  set(QT4_INSTALLED TRUE)
endif()
set(GLOB_TEMP_VAR)

if (Qt_FIND_VERSION)
  if (Qt_FIND_VERSION MATCHES "^([34])(\\.[0-9]+.*)?$")
    set(DESIRED_QT_VERSION ${CMAKE_MATCH_1})
  else ()
    message(FATAL_ERROR "FindQt was called with invalid version '${Qt_FIND_VERSION}'. Only Qt major versions 3 or 4 are supported. If you do not need to support both Qt3 and Qt4 in your source consider calling find_package(Qt3) or find_package(Qt4) instead of find_package(Qt) instead.")
  endif ()
endif ()

# now find qmake
find_program(QT_QMAKE_EXECUTABLE_FINDQT NAMES qmake PATHS "${QT_SEARCH_PATH}/bin" "$ENV{QTDIR}/bin")
if(QT_QMAKE_EXECUTABLE_FINDQT)
  exec_program(${QT_QMAKE_EXECUTABLE_FINDQT} ARGS "-query QT_VERSION"
    OUTPUT_VARIABLE QTVERSION)
  if(QTVERSION MATCHES "4")
    set(QT_QMAKE_EXECUTABLE ${QT_QMAKE_EXECUTABLE_FINDQT} CACHE PATH "Qt4 qmake program.")
    set(QT4_INSTALLED TRUE)
  endif()
  if(QTVERSION MATCHES "Unknown")
    set(QT3_INSTALLED TRUE)
  endif()
endif()

if(QT_QMAKE_EXECUTABLE_FINDQT)
  exec_program( ${QT_QMAKE_EXECUTABLE_FINDQT}
    ARGS "-query QT_INSTALL_HEADERS"
    OUTPUT_VARIABLE qt_headers )
endif()

find_file( QT4_QGLOBAL_H_FILE qglobal.h
  "${QT_SEARCH_PATH}/Qt/include"
  "[HKEY_CURRENT_USER\\Software\\Trolltech\\Qt3Versions\\4.0.0;InstallDir]/include/Qt"
  "[HKEY_CURRENT_USER\\Software\\Trolltech\\Versions\\4.0.0;InstallDir]/include/Qt"
  ${qt_headers}/Qt
  $ENV{QTDIR}/include/Qt
  /usr/lib/qt/include/Qt
  /usr/share/qt4/include/Qt
  /usr/local/include/X11/qt4/Qt
  C:/Progra~1/qt/include/Qt
  PATH_SUFFIXES qt/include/Qt include/Qt)

if(QT4_QGLOBAL_H_FILE)
  set(QT4_INSTALLED TRUE)
endif()

find_file( QT3_QGLOBAL_H_FILE qglobal.h
  "${QT_SEARCH_PATH}/Qt/include"
 "[HKEY_CURRENT_USER\\Software\\Trolltech\\Qt3Versions\\3.2.1;InstallDir]/include/Qt"
  "[HKEY_CURRENT_USER\\Software\\Trolltech\\Qt3Versions\\3.2.0;InstallDir]/include/Qt"
  "[HKEY_CURRENT_USER\\Software\\Trolltech\\Qt3Versions\\3.1.0;InstallDir]/include/Qt"
  C:/Qt/3.3.3Educational/include
  $ENV{QTDIR}/include
  /usr/include/qt3/Qt
  /usr/share/qt3/include
  /usr/local/include/X11/qt3
  C:/Progra~1/qt/include
  PATH_SUFFIXES qt/include include/qt3)

if(QT3_QGLOBAL_H_FILE)
  set(QT3_INSTALLED TRUE)
endif()

if(QT3_INSTALLED AND QT4_INSTALLED AND NOT DESIRED_QT_VERSION)
  # force user to pick if we have both
  set(DESIRED_QT_VERSION 0 CACHE STRING "Pick a version of Qt to use: 3 or 4")
else()
  # if only one found then pick that one
  if(QT3_INSTALLED AND NOT DESIRED_QT_VERSION EQUAL 4)
    set(DESIRED_QT_VERSION 3 CACHE STRING "Pick a version of Qt to use: 3 or 4")
  endif()
  if(QT4_INSTALLED AND NOT DESIRED_QT_VERSION EQUAL 3)
    set(DESIRED_QT_VERSION 4 CACHE STRING "Pick a version of Qt to use: 3 or 4")
  endif()
endif()

if(DESIRED_QT_VERSION EQUAL 3)
  set(Qt3_FIND_REQUIRED ${Qt_FIND_REQUIRED})
  set(Qt3_FIND_QUIETLY  ${Qt_FIND_QUIETLY})
  include(${CMAKE_CURRENT_LIST_DIR}/FindQt3.cmake)
endif()
if(DESIRED_QT_VERSION EQUAL 4)
  set(Qt4_FIND_REQUIRED ${Qt_FIND_REQUIRED})
  set(Qt4_FIND_QUIETLY  ${Qt_FIND_QUIETLY})
  include(${CMAKE_CURRENT_LIST_DIR}/FindQt4.cmake)
endif()

if(NOT QT3_INSTALLED AND NOT QT4_INSTALLED)
  if(QT_REQUIRED)
    message(SEND_ERROR "CMake was unable to find any Qt versions, put qmake in your path, or set QT_QMAKE_EXECUTABLE.")
  endif()
else()
  if(NOT QT_FOUND AND NOT DESIRED_QT_VERSION)
    if(QT_REQUIRED)
      message(SEND_ERROR "Multiple versions of Qt found please set DESIRED_QT_VERSION")
    else()
      message("Multiple versions of Qt found please set DESIRED_QT_VERSION")
    endif()
  endif()
  if(NOT QT_FOUND AND DESIRED_QT_VERSION)
    if(QT_REQUIRED)
      message(FATAL_ERROR "CMake was unable to find Qt version: ${DESIRED_QT_VERSION}. Set advanced values QT_QMAKE_EXECUTABLE and QT${DESIRED_QT_VERSION}_QGLOBAL_H_FILE, if those are set then QT_QT_LIBRARY or QT_LIBRARY_DIR.")
    else()
      message( "CMake was unable to find desired Qt version: ${DESIRED_QT_VERSION}. Set advanced values QT_QMAKE_EXECUTABLE and QT${DESIRED_QT_VERSION}_QGLOBAL_H_FILE.")
    endif()
  endif()
endif()
mark_as_advanced(QT3_QGLOBAL_H_FILE QT4_QGLOBAL_H_FILE QT_QMAKE_EXECUTABLE_FINDQT)