CMake: Allow for changing the bin install dir

Also, use the standard CMake option name for the man dir.

CMakeLists.txt

@@ -14,8 +14,22 @@ option(USE_STATIC_LIBS "Statically link libraries" OFF)
 option(ZLIB_USE_STATIC_LIBS "Statically link libz" OFF)
 option(BZip2_USE_STATIC_LIBS "Statically link libbz2" OFF)
 
-set(MAN_DIR "share/man" CACHE STRING "Install path for man pages (relative to prefix).")
-mark_as_advanced(MAN_DIR)
+# Install destinations
+if(NOT WIN32)
+	if(CMAKE_VERSION VERSION_LESS 2.8.5)
+		set(CMAKE_INSTALL_DATAROOTDIR "share" CACHE
+		    STRING "read-only architecture-independent data root (share) (relative to prefix).")
+		mark_as_advanced(CMAKE_INSTALL_DATAROOTDIR)
+		set(CMAKE_INSTALL_BINDIR "bin" CACHE
+		    STRING "user executables (bin) (relative to prefix).")
+		mark_as_advanced(CMAKE_INSTALL_BINDIR)
+		set(CMAKE_INSTALL_MANDIR "${CMAKE_INSTALL_DATAROOTDIR}/man" CACHE
+		    STRING "man documentation (DATAROOTDIR/man) (relative to prefix).")
+		mark_as_advanced(CMAKE_INSTALL_MANDIR)
+	else()
+		include(GNUInstallDirs)
+	endif()
+endif()
 
 
 # Helper scrips
@@ -288,9 +302,9 @@ list(APPEND INNOEXTRACT_SOURCES "${VERSION_FILE}")
 add_executable(innoextract ${INNOEXTRACT_SOURCES} ${ALL_INCLUDES})
 target_link_libraries(innoextract ${LIBRARIES})
 
-install(TARGETS innoextract RUNTIME DESTINATION bin)
+install(TARGETS innoextract RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
 
-install(FILES doc/innoextract.1 DESTINATION ${MAN_DIR}/man1 OPTIONAL)
+install(FILES doc/innoextract.1 DESTINATION ${CMAKE_INSTALL_MANDIR}/man1 OPTIONAL)
 
 
 # Additional targets.

README.md

@@ -44,12 +44,10 @@ Build options:
 |:------------------------ |:------------:|:----------- |
 | `USE_LZMA`               | `ON`         | Use `liblzma` if available.
 | `CMAKE_BUILD_TYPE`       | `Release`    | Set to `Debug` to enable debug output.
-| `CMAKE_INSTALL_PREFIX`   | `/usr/local` | Where to install innoextract.
 | `SET_WARNING_FLAGS`      | `ON`         | Adjust compiler warning flags. This should not affect the produced binaries but is useful to catch potential problems.
 | `SET_OPTIMIZATION_FLAGS` | `ON`         | Adjust compiler optimization flags. For non-debug builds the only thing this does is instruct the linker to only link against libraries that are actually needed.
 | `USE_CXX11`              | `ON`         | Try to compile in C++11 mode if available.
 | `DEBUG_EXTRA`            | `OFF`        | Expensive debug options.
-| `MAN_DIR`                | `share/man`  | Install location for man pages (relative to prefix). |
 | `USE_STATIC_LIBS`        | `OFF`        | Turns on static linking for all libraries, including `-static-libgcc` and `-static-libstdc++`. You can also use the individual options below:
 | `LZMA_USE_STATIC_LIBS`   | `OFF`        | Statically link `liblzma`.
 | `Boost_USE_STATIC_LIBS`  | `OFF`        | Statically link Boost. See also `FindBoost.cmake`
@@ -57,6 +55,15 @@ Build options:
 | `BZip2_USE_STATIC_LIBS`  | `OFF`        | Statically link `libbz2`. (used via Boost)
 | `iconv_USE_STATIC_LIBS`  | `OFF`        | Statically link `libiconv`.
 
+Install options:
+
+| Option                      | Default              | Description |
+|:--------------------------- |:--------------------:|:----------- |
+| `CMAKE_INSTALL_PREFIX`      | `/usr/local`         | Where to install innoextract.
+| `CMAKE_INSTALL_BINDIR`      | `bin`                | Location for binaries (relative to prefix).
+| `CMAKE_INSTALL_DATAROOTDIR` | `share/man`          | Location for data files (relative to prefix).
+| `CMAKE_INSTALL_MANDIR`      | `${DATAROOTDIR}/man` | Location for man pages (relative to prefix).
+
 Set options by passing `-D<option>=<value>` to cmake.
 
 ## Run