CMake/Modules/FindGIF.cmake
Rolf Eike Beer 745b56f58c Find*.cmake: drop the comments before including FPHSA
No need to explain this over and over again.  While at it, do some other
minor cleanups to whitespace and comments (i.e. delete them).
2016-11-28 16:40:13 -05:00

99 lines
3.0 KiB
CMake

# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.
#.rst:
# FindGIF
# -------
#
# This finds the GIF library (giflib)
#
# The module defines the following variables:
#
# ``GIF_FOUND``
# True if giflib was found
# ``GIF_LIBRARIES``
# Libraries to link to in order to use giflib
# ``GIF_INCLUDE_DIR``
# where to find the headers
# ``GIF_VERSION``
# 3, 4 or a full version string (eg 5.1.4) for versions >= 4.1.6
#
# The minimum required version of giflib can be specified using the
# standard syntax, e.g. find_package(GIF 4)
#
# $GIF_DIR is an environment variable that would correspond to the
# ./configure --prefix=$GIF_DIR
# Created by Eric Wing.
# Modifications by Alexander Neundorf, Ben Campbell
find_path(GIF_INCLUDE_DIR gif_lib.h
HINTS
ENV GIF_DIR
PATH_SUFFIXES include
PATHS
~/Library/Frameworks
/usr/freeware
)
# the gif library can have many names :-/
set(POTENTIAL_GIF_LIBS gif libgif ungif libungif giflib giflib4)
find_library(GIF_LIBRARY
NAMES ${POTENTIAL_GIF_LIBS}
HINTS
ENV GIF_DIR
PATH_SUFFIXES lib
PATHS
~/Library/Frameworks
/usr/freeware
)
# see readme.txt
set(GIF_LIBRARIES ${GIF_LIBRARY})
# Very basic version detection.
# The GIF_LIB_VERSION string in gif_lib.h seems to be unreliable, since it seems
# to be always " Version 2.0, " in versions 3.x of giflib.
# In version 4 the member UserData was added to GifFileType, so we check for this
# one.
# Versions after 4.1.6 define GIFLIB_MAJOR, GIFLIB_MINOR, and GIFLIB_RELEASE
# see http://giflib.sourceforge.net/gif_lib.html#compatibility
if(GIF_INCLUDE_DIR)
include(${CMAKE_CURRENT_LIST_DIR}/CMakePushCheckState.cmake)
include(${CMAKE_CURRENT_LIST_DIR}/CheckStructHasMember.cmake)
CMAKE_PUSH_CHECK_STATE()
set(CMAKE_REQUIRED_QUIET ${GIF_FIND_QUIETLY})
set(CMAKE_REQUIRED_INCLUDES "${GIF_INCLUDE_DIR}")
# Check for the specific version defines (>=4.1.6 only)
file(STRINGS ${GIF_INCLUDE_DIR}/gif_lib.h _GIF_DEFS REGEX "^[ \t]*#define[ \t]+GIFLIB_(MAJOR|MINOR|RELEASE)")
if(_GIF_DEFS)
# yay - got exact version info
string(REGEX REPLACE ".*GIFLIB_MAJOR ([0-9]+).*" "\\1" _GIF_MAJ "${_GIF_DEFS}")
string(REGEX REPLACE ".*GIFLIB_MINOR ([0-9]+).*" "\\1" _GIF_MIN "${_GIF_DEFS}")
string(REGEX REPLACE ".*GIFLIB_RELEASE ([0-9]+).*" "\\1" _GIF_REL "${_GIF_DEFS}")
set(GIF_VERSION "${_GIF_MAJ}.${_GIF_MIN}.${_GIF_REL}")
else()
# use UserData field to sniff version instead
CHECK_STRUCT_HAS_MEMBER(GifFileType UserData gif_lib.h GIF_GifFileType_UserData )
if(GIF_GifFileType_UserData)
set(GIF_VERSION 4)
else()
set(GIF_VERSION 3)
endif()
endif()
unset(_GIF_MAJ)
unset(_GIF_MIN)
unset(_GIF_REL)
unset(_GIF_DEFS)
CMAKE_POP_CHECK_STATE()
endif()
include(${CMAKE_CURRENT_LIST_DIR}/FindPackageHandleStandardArgs.cmake)
FIND_PACKAGE_HANDLE_STANDARD_ARGS(GIF REQUIRED_VARS GIF_LIBRARY GIF_INCLUDE_DIR
VERSION_VAR GIF_VERSION )
mark_as_advanced(GIF_INCLUDE_DIR GIF_LIBRARY)