QGIS/cmake/FindProj.cmake

# Find Proj
# ~~~~~~~~~
# Copyright (c) 2007, Martin Dobias <wonder.sk at gmail.com>
# Redistribution and use is allowed according to the terms of the BSD license.
# For details see the accompanying COPYING-CMAKE-SCRIPTS file.
#
# CMake module to search for Proj library
#
# If it's found it sets PROJ_FOUND to TRUE
# and following variables are set:
#    PROJ_INCLUDE_DIR
#    PROJ_LIBRARY

# FIND_PATH and FIND_LIBRARY normally search standard locations
# before the specified paths. To search non-standard paths first,
# FIND_* is invoked first with specified paths and NO_DEFAULT_PATH
# and then again with no specified paths to search the default
# locations. When an earlier FIND_* succeeds, subsequent FIND_*s
# searching for the same item do nothing.

# 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_PATH(PROJ_INCLUDE_DIR PROJ/proj_api.h)
    FIND_LIBRARY(PROJ_LIBRARY PROJ)
    IF (PROJ_LIBRARY)
      # FIND_PATH doesn't add "Headers" for a framework
      SET (PROJ_INCLUDE_DIR ${PROJ_LIBRARY}/Headers CACHE PATH "Path to a file.")
    ENDIF (PROJ_LIBRARY)
    SET (CMAKE_FIND_FRAMEWORK ${CMAKE_FIND_FRAMEWORK_save} CACHE STRING "" FORCE)
  ENDIF ()
ENDIF (APPLE)

FIND_PATH(PROJ_INCLUDE_DIR proj_api.h
  "$ENV{INCLUDE}"
  "$ENV{LIB_DIR}/include"
  )

FIND_LIBRARY(PROJ_LIBRARY NAMES proj_i proj PATHS
  "$ENV{LIB}"
  "$ENV{LIB_DIR}/lib"
  )

IF (PROJ_INCLUDE_DIR AND PROJ_LIBRARY)
   SET(PROJ_FOUND TRUE)
ENDIF (PROJ_INCLUDE_DIR AND PROJ_LIBRARY)

IF (PROJ_FOUND)
   IF (EXISTS ${PROJ_INCLUDE_DIR}/proj.h)
     FILE(READ ${PROJ_INCLUDE_DIR}/proj.h proj_version)
     STRING(REGEX REPLACE "^.*PROJ_VERSION_MAJOR +([0-9]+).*$" "\\1" PROJ_VERSION_MAJOR "${proj_version}")
     STRING(REGEX REPLACE "^.*PROJ_VERSION_MINOR +([0-9]+).*$" "\\1" PROJ_VERSION_MINOR "${proj_version}")
     STRING(REGEX REPLACE "^.*PROJ_VERSION_PATCH +([0-9]+).*$" "\\1" PROJ_VERSION_PATCH "${proj_version}")
     STRING(CONCAT PROJ_VERSION_STR "(" ${PROJ_VERSION_MAJOR} "." ${PROJ_VERSION_MINOR} "." ${PROJ_VERSION_PATCH} ")")
     IF ((PROJ_VERSION_MAJOR EQUAL 6) AND (PROJ_VERSION_MINOR EQUAL 0))
       MESSAGE (FATAL_ERROR "Cannot build QGIS using Proj ${PROJ_VERSION_MAJOR}.${PROJ_VERSION_MINOR}.${PROJ_VERSION_PATCH} Use 6.1.0 or higher.")
     ENDIF ((PROJ_VERSION_MAJOR EQUAL 6) AND (PROJ_VERSION_MINOR EQUAL 0))
   ELSE(EXISTS ${PROJ_INCLUDE_DIR}/proj.h)
     FILE(READ ${PROJ_INCLUDE_DIR}/proj_api.h proj_version)
     STRING(REGEX REPLACE "^.*PJ_VERSION ([0-9]+).*$" "\\1" PJ_VERSION "${proj_version}")

     # This will break if 4.10.0 ever will be released (highly unlikely)
     STRING(REGEX REPLACE "([0-9])([0-9])([0-9])" "\\1" PROJ_VERSION_MAJOR "${PJ_VERSION}")
     STRING(REGEX REPLACE "([0-9])([0-9])([0-9])" "\\2" PROJ_VERSION_MINOR "${PJ_VERSION}")
     STRING(REGEX REPLACE "([0-9])([0-9])([0-9])" "\\3" PROJ_VERSION_PATCH "${PJ_VERSION}")
     STRING(CONCAT PROJ_VERSION_STR "(" ${PROJ_VERSION_MAJOR} "." ${PROJ_VERSION_MINOR} "." ${PROJ_VERSION_PATCH} ")")

     # Minimum Proj version required is 4.9.3
     IF ((PROJ_VERSION_MAJOR EQUAL 4) AND ((PROJ_VERSION_MINOR LESS 9) OR ((PROJ_VERSION_MINOR EQUAL 9) AND (PROJ_VERSION_PATCH LESS 3))))
       MESSAGE(FATAL_ERROR "Found Proj: ${PROJ_VERSION_MAJOR}.${PROJ_VERSION_MINOR}.${PROJ_VERSION_PATCH}. Cannot build QGIS using Proj older than 4.9.3.")
     ENDIF((PROJ_VERSION_MAJOR EQUAL 4) AND ((PROJ_VERSION_MINOR LESS 9) OR ((PROJ_VERSION_MINOR EQUAL 9) AND (PROJ_VERSION_PATCH LESS 3))))
   ENDIF(EXISTS ${PROJ_INCLUDE_DIR}/proj.h)
   IF (NOT PROJ_FIND_QUIETLY)
     MESSAGE(STATUS "Found Proj: ${PROJ_LIBRARY} version ${PROJ_VERSION_MAJOR} ${PROJ_VERSION_STR}")
   ENDIF (NOT PROJ_FIND_QUIETLY)

   ADD_DEFINITIONS(-DPROJ_VERSION_MAJOR=${PROJ_VERSION_MAJOR})

ELSE (PROJ_FOUND)

   IF (PROJ_FIND_REQUIRED)
      MESSAGE(FATAL_ERROR "Could not find Proj")
   ENDIF (PROJ_FIND_REQUIRED)

ENDIF (PROJ_FOUND)