nextcloud-desktop/cmake/Modules/FindLibSSH.cmake

# - Try to find LibSSH
# Once done this will define
#
#  LIBSSH_FOUND - system has LibSSH
#  LIBSSH_INCLUDE_DIRS - the LibSSH include directory
#  LIBSSH_LIBRARIES - Link these to use LibSSH
#  LIBSSH_DEFINITIONS - Compiler switches required for using LibSSH
#
#  Copyright (c) 2009 Andreas Schneider <mail@cynapses.org>
#
#  Redistribution and use is allowed according to the terms of the New
#  BSD license.
#  For details see the accompanying COPYING-CMAKE-SCRIPTS file.
#

if (LIBSSH_LIBRARIES AND LIBSSH_INCLUDE_DIRS)
  # in cache already
  set(LIBSSH_FOUND TRUE)
else (LIBSSH_LIBRARIES AND LIBSSH_INCLUDE_DIRS)

  find_path(LIBSSH_INCLUDE_DIR
    NAMES
      libssh/libssh.h
    PATHS
      /usr/include
      /usr/local/include
      /opt/local/include
      /sw/include
      ${CMAKE_INCLUDE_PATH}
      ${CMAKE_INSTALL_PREFIX}/include
  )
  
  find_library(SSH_LIBRARY
    NAMES
      ssh
      libssh
    PATHS
      /usr/lib
      /usr/local/lib
      /opt/local/lib
      /sw/lib
      ${CMAKE_LIBRARY_PATH}
      ${CMAKE_INSTALL_PREFIX}/lib
  )

  if (LIBSSH_INCLUDE_DIR AND SSH_LIBRARY)
    set(SSH_FOUND TRUE)
  endif (LIBSSH_INCLUDE_DIR AND SSH_LIBRARY)

  set(LIBSSH_INCLUDE_DIRS
    ${LIBSSH_INCLUDE_DIR}
  )

  if (SSH_FOUND)
    set(LIBSSH_LIBRARIES
      ${LIBSSH_LIBRARIES}
      ${SSH_LIBRARY}
    )

    if (LibSSH_FIND_VERSION)
      file(STRINGS ${LIBSSH_INCLUDE_DIR}/libssh/libssh.h LIBSSH_VERSION_MAJOR
        REGEX "#define[ ]+LIBSSH_VERSION_MAJOR[ ]+[0-9]+")
      # Older versions of libssh like libssh-0.2 have LIBSSH_VERSION but not LIBSSH_VERSION_MAJOR
      if (LIBSSH_VERSION_MAJOR)
        string(REGEX MATCH "[0-9]+" LIBSSH_VERSION_MAJOR ${LIBSSH_VERSION_MAJOR})
	file(STRINGS ${LIBSSH_INCLUDE_DIR}/libssh/libssh.h LIBSSH_VERSION_MINOR
          REGEX "#define[ ]+LIBSSH_VERSION_MINOR[ ]+[0-9]+")
	string(REGEX MATCH "[0-9]+" LIBSSH_VERSION_MINOR ${LIBSSH_VERSION_MINOR})
	file(STRINGS ${LIBSSH_INCLUDE_DIR}/libssh/libssh.h LIBSSH_VERSION_PATCH
          REGEX "#define[ ]+LIBSSH_VERSION_MICRO[ ]+[0-9]+")
	string(REGEX MATCH "[0-9]+" LIBSSH_VERSION_PATCH ${LIBSSH_VERSION_PATCH})

	set(LibSSH_VERSION ${LIBSSH_VERSION_MAJOR}.${LIBSSH_VERSION_MINOR}.${LIBSSH_VERSION_PATCH})

	include(FindPackageVersionCheck)
	find_package_version_check(LibSSH DEFAULT_MSG)
      else (LIBSSH_VERSION_MAJOR)
        message(STATUS "LIBSSH_VERSION_MAJOR not found in ${LIBSSH_INCLUDE_DIR}/libssh/libssh.h, assuming libssh is too old")
        set(LIBSSH_FOUND FALSE)
      endif (LIBSSH_VERSION_MAJOR)
    endif (LibSSH_FIND_VERSION)
  endif (SSH_FOUND)

  # If the version is too old, but libs and includes are set,
  # find_package_handle_standard_args will set LIBSSH_FOUND to TRUE again,
  # so we need this if() here.
  if (LIBSSH_FOUND)
    include(FindPackageHandleStandardArgs)
    find_package_handle_standard_args(LibSSH DEFAULT_MSG LIBSSH_LIBRARIES LIBSSH_INCLUDE_DIRS)
  endif (LIBSSH_FOUND)

  # show the LIBSSH_INCLUDE_DIRS and LIBSSH_LIBRARIES variables only in the advanced view
  mark_as_advanced(LIBSSH_INCLUDE_DIRS LIBSSH_LIBRARIES)

endif (LIBSSH_LIBRARIES AND LIBSSH_INCLUDE_DIRS)