QGIS/cmake/FindGDAL.cmake

# Find GDAL
# ~~~~~~~~~
# Copyright (c) 2007, Magnus Homann <magnus at homann dot se>
# Redistribution and use is allowed according to the terms of the BSD license.
# For details see the accompanying COPYING-CMAKE-SCRIPTS file.
#
#
# Once run this will define: 
# 
# GDAL_FOUND       = system has GDAL lib
#
# GDAL_LIBRARY     = full path to the library
#
# GDAL_INCLUDE_DIR      = where to find headers 

INCLUDE (${CMAKE_SOURCE_DIR}/cmake/MacPlistMacros.cmake)

IF(WIN32)

  IF (MINGW)
    FIND_PATH(GDAL_INCLUDE_DIR gdal.h /usr/local/include /usr/include c:/msys/local/include)
    FIND_LIBRARY(GDAL_LIBRARY NAMES gdal PATHS /usr/local/lib /usr/lib c:/msys/local/lib)
  ENDIF (MINGW)

  IF (MSVC)
    FIND_PATH(GDAL_INCLUDE_DIR gdal.h "$ENV{LIB_DIR}/include/gdal" $ENV{INCLUDE})
    FIND_LIBRARY(GDAL_LIBRARY NAMES gdal gdal_i PATHS 
	    "$ENV{LIB_DIR}/lib" $ENV{LIB} /usr/lib c:/msys/local/lib)
    IF (GDAL_LIBRARY)
      SET (
         GDAL_LIBRARY;odbc32;odbccp32 
         CACHE STRING INTERNAL)
    ENDIF (GDAL_LIBRARY)
  ENDIF (MSVC)
  
  
ELSE(WIN32)
  IF(UNIX) 

    # try to use framework on mac
    # want clean framework path, not unix compatibility path
    IF (APPLE)
      IF (CMAKE_FIND_FRAMEWORK MATCHES "FIRST"
          OR CMAKE_FRAMEWORK_PATH MATCHES "ONLY"
          OR NOT CMAKE_FIND_FRAMEWORK)
        SET (CMAKE_FIND_FRAMEWORK_save ${CMAKE_FIND_FRAMEWORK} CACHE STRING "" FORCE)
        SET (CMAKE_FIND_FRAMEWORK "ONLY" CACHE STRING "" FORCE)
        FIND_LIBRARY(GDAL_LIBRARY GDAL)
        IF (GDAL_LIBRARY)
          # they're all the same in a framework
          SET (GDAL_INCLUDE_DIR ${GDAL_LIBRARY}/Headers CACHE PATH "Path to a file.")
          # set GDAL_CONFIG to make later test happy, not used here, may not exist
          SET (GDAL_CONFIG ${GDAL_LIBRARY}/unix/bin/gdal-config CACHE FILEPATH "Path to a program.")
          # version in info.plist
          GET_VERSION_PLIST (${GDAL_LIBRARY}/Resources/Info.plist GDAL_VERSION)
          IF (NOT GDAL_VERSION)
            MESSAGE (FATAL_ERROR "Could not determine GDAL version from framework.")
          ENDIF (NOT GDAL_VERSION)
          STRING(REGEX REPLACE "([0-9]+)\\.([0-9]+)\\.([0-9]+)" "\\1" GDAL_VERSION_MAJOR "${GDAL_VERSION}")
          STRING(REGEX REPLACE "([0-9]+)\\.([0-9]+)\\.([0-9]+)" "\\2" GDAL_VERSION_MINOR "${GDAL_VERSION}")
          IF (GDAL_VERSION_MAJOR LESS 2)
            MESSAGE (FATAL_ERROR "GDAL version is too old (${GDAL_VERSION}). Use 2.1 or higher.")
          ENDIF (GDAL_VERSION_MAJOR LESS 2)
          IF ( (GDAL_VERSION_MAJOR EQUAL 2) AND (GDAL_VERSION_MINOR LESS 1) )
            MESSAGE (FATAL_ERROR "GDAL version is too old (${GDAL_VERSION}). Use 2.1 or higher.")
          ENDIF( (GDAL_VERSION_MAJOR EQUAL 2) AND (GDAL_VERSION_MINOR LESS 1) )

        ENDIF (GDAL_LIBRARY)
        SET (CMAKE_FIND_FRAMEWORK ${CMAKE_FIND_FRAMEWORK_save} CACHE STRING "" FORCE)
      ENDIF ()
    ENDIF (APPLE)

    IF(CYGWIN)
      FIND_LIBRARY(GDAL_LIBRARY NAMES gdal PATHS /usr/lib /usr/local/lib)
    ENDIF(CYGWIN)

    IF (NOT GDAL_INCLUDE_DIR OR NOT GDAL_LIBRARY OR NOT GDAL_CONFIG)
      # didn't find OS X framework, and was not set by user
      SET(GDAL_CONFIG_PREFER_PATH "$ENV{GDAL_HOME}/bin" CACHE STRING "preferred path to GDAL (gdal-config)")
      SET(GDAL_CONFIG_PREFER_FWTOOLS_PATH "$ENV{FWTOOLS_HOME}/bin_safe" CACHE STRING "preferred path to GDAL (gdal-config) from FWTools")
      FIND_PROGRAM(GDAL_CONFIG gdal-config
          ${GDAL_CONFIG_PREFER_PATH}
          ${GDAL_CONFIG_PREFER_FWTOOLS_PATH}
          /usr/local/bin/
          /usr/bin/
          )
      # MESSAGE("DBG GDAL_CONFIG ${GDAL_CONFIG}")
    
      IF (GDAL_CONFIG) 

        ## extract gdal version 
        EXEC_PROGRAM(${GDAL_CONFIG}
            ARGS --version
            OUTPUT_VARIABLE GDAL_VERSION )
        STRING(REGEX REPLACE "([0-9]+)\\.([0-9]+)\\.([0-9]+)" "\\1" GDAL_VERSION_MAJOR "${GDAL_VERSION}")
        STRING(REGEX REPLACE "([0-9]+)\\.([0-9]+)\\.([0-9]+)" "\\2" GDAL_VERSION_MINOR "${GDAL_VERSION}")
  
        # MESSAGE("DBG GDAL_VERSION ${GDAL_VERSION}")
        # MESSAGE("DBG GDAL_VERSION_MAJOR ${GDAL_VERSION_MAJOR}")
        # MESSAGE("DBG GDAL_VERSION_MINOR ${GDAL_VERSION_MINOR}")
  
        # check for gdal version
        # version 1.2.5 is known NOT to be supported (missing CPL_STDCALL macro)
        # According to INSTALL, 2.1+ is required
        IF (GDAL_VERSION_MAJOR LESS 2)
          MESSAGE (FATAL_ERROR "GDAL version is too old (${GDAL_VERSION}). Use 2.1 or higher.")
        ENDIF (GDAL_VERSION_MAJOR LESS 2)
        IF ( (GDAL_VERSION_MAJOR EQUAL 2) AND (GDAL_VERSION_MINOR LESS 1) )
          MESSAGE (FATAL_ERROR "GDAL version is too old (${GDAL_VERSION}). Use 2.1 or higher.")
        ENDIF( (GDAL_VERSION_MAJOR EQUAL 2) AND (GDAL_VERSION_MINOR LESS 1) )

        # set INCLUDE_DIR to prefix+include
        EXEC_PROGRAM(${GDAL_CONFIG}
            ARGS --prefix
            OUTPUT_VARIABLE GDAL_PREFIX)
        #SET(GDAL_INCLUDE_DIR ${GDAL_PREFIX}/include CACHE STRING INTERNAL)
        FIND_PATH(GDAL_INCLUDE_DIR 
            gdal.h 
            ${GDAL_PREFIX}/include/gdal
            ${GDAL_PREFIX}/include
            /usr/local/include 
            /usr/include 
            )

        ## extract link dirs for rpath  
        EXEC_PROGRAM(${GDAL_CONFIG}
            ARGS --libs
            OUTPUT_VARIABLE GDAL_CONFIG_LIBS )

        ## split off the link dirs (for rpath)
        ## use regular expression to match wildcard equivalent "-L*<endchar>"
        ## with <endchar> is a space or a semicolon
        STRING(REGEX MATCHALL "[-][L]([^ ;])+" 
            GDAL_LINK_DIRECTORIES_WITH_PREFIX 
            "${GDAL_CONFIG_LIBS}" )
        #      MESSAGE("DBG  GDAL_LINK_DIRECTORIES_WITH_PREFIX=${GDAL_LINK_DIRECTORIES_WITH_PREFIX}")

        ## remove prefix -L because we need the pure directory for LINK_DIRECTORIES
      
        IF (GDAL_LINK_DIRECTORIES_WITH_PREFIX)
          STRING(REGEX REPLACE "[-][L]" "" GDAL_LINK_DIRECTORIES ${GDAL_LINK_DIRECTORIES_WITH_PREFIX} )
        ENDIF (GDAL_LINK_DIRECTORIES_WITH_PREFIX)

        ## split off the name
        ## use regular expression to match wildcard equivalent "-l*<endchar>"
        ## with <endchar> is a space or a semicolon
        STRING(REGEX MATCHALL "[-][l]([^ ;])+" 
            GDAL_LIB_NAME_WITH_PREFIX 
            "${GDAL_CONFIG_LIBS}" )
        #      MESSAGE("DBG  GDAL_LIB_NAME_WITH_PREFIX=${GDAL_LIB_NAME_WITH_PREFIX}")


        ## remove prefix -l because we need the pure name
      
        IF (GDAL_LIB_NAME_WITH_PREFIX)
          STRING(REGEX REPLACE "[-][l]" "" GDAL_LIB_NAME ${GDAL_LIB_NAME_WITH_PREFIX} )
        ENDIF (GDAL_LIB_NAME_WITH_PREFIX)

        IF (APPLE)
          IF (NOT GDAL_LIBRARY)
            # work around empty GDAL_LIBRARY left by framework check
            # while still preserving user setting if given
            # ***FIXME*** need to improve framework check so below not needed
            SET(GDAL_LIBRARY ${GDAL_LINK_DIRECTORIES}/lib${GDAL_LIB_NAME}.dylib CACHE STRING INTERNAL FORCE)
          ENDIF (NOT GDAL_LIBRARY)
        ELSE (APPLE)
          FIND_LIBRARY(GDAL_LIBRARY NAMES ${GDAL_LIB_NAME} PATHS ${GDAL_LINK_DIRECTORIES}/lib)
        ENDIF (APPLE)
      
      ELSE(GDAL_CONFIG)
        MESSAGE("FindGDAL.cmake: gdal-config not found. Please set it manually. GDAL_CONFIG=${GDAL_CONFIG}")
      ENDIF(GDAL_CONFIG)
    ENDIF (NOT GDAL_INCLUDE_DIR OR NOT GDAL_LIBRARY OR NOT GDAL_CONFIG)
  ENDIF(UNIX)
ENDIF(WIN32)


IF (GDAL_INCLUDE_DIR AND GDAL_LIBRARY)
   SET(GDAL_FOUND TRUE)
ENDIF (GDAL_INCLUDE_DIR AND GDAL_LIBRARY)

IF (GDAL_FOUND)

   IF (NOT GDAL_FIND_QUIETLY)
      FILE(READ ${GDAL_INCLUDE_DIR}/gdal_version.h gdal_version)
      STRING(REGEX REPLACE "^.*GDAL_RELEASE_NAME +\"([^\"]+)\".*$" "\\1" GDAL_RELEASE_NAME "${gdal_version}")

      MESSAGE(STATUS "Found GDAL: ${GDAL_LIBRARY} (${GDAL_RELEASE_NAME})")
   ENDIF (NOT GDAL_FIND_QUIETLY)

ELSE (GDAL_FOUND)

   MESSAGE(GDAL_INCLUDE_DIR=${GDAL_INCLUDE_DIR})
   MESSAGE(GDAL_LIBRARY=${GDAL_LIBRARY})
   MESSAGE(FATAL_ERROR "Could not find GDAL")

ENDIF (GDAL_FOUND)