diff options
| -rw-r--r-- | CMakeLists.txt | 82 |
1 files changed, 75 insertions, 7 deletions
diff --git a/CMakeLists.txt b/CMakeLists.txt index 7aed9d9f..6a12abc3 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -1175,6 +1175,62 @@ if(NOT MSVC AND HAVE_GETOPT_LONG) list(APPEND XZ_LINKS "lzma" "unlzma" "lzcat") endif() + # With Windows Cygwin and MSYS2 the symlinking is complicated. Both + # of these environments set the UNIX variable so they will try to + # make the symlinks. The ability for Cygwin and MSYS2 to make + # broken symlinks is determined by the CYGWIN and MSYS2 environment + # variables, repectively. Broken symlinks are needed for the man + # page symlinks and for determining if the xz and lzma symlinks need + # to depend on the xz target or not. If broken symlinks cannot be + # made then the xz binary must be created before the symlinks. + set(ALLOW_BROKEN_SYMLINKS ON) + + if(CMAKE_SYSTEM_NAME STREQUAL "CYGWIN") + # The Cygwin env variable can be set to four possible values: + # + # 1. "lnk". Create symlinks as Windows shortcuts. + # + # 2. "native". Create symlinks as native Windows symlinks + # if supported by the system. Fallback to "lnk" if native + # symlinks are not supported. + # + # 3. "nativestrict". Create symlinks as native Windows symlinks + # if supported by the system. If the target of the symlink + # does not exist or the creation of the symlink fails for any + # reason, do not create the symlink. + # + # 4. "sys". Create symlinks as plain files with a special + # system attribute containing the path to the symlink target. + # + # So, the only case we care about for broken symlinks is + # "nativestrict" since all other values mean that broken + # symlinks are allowed. If the env variable is not set the + # default is "native". If the env varaiable is set but not + # assigned one of the four values, then the default is the same + # as option 1 "lnk". + string(FIND "$ENV{CYGWIN}" "winsymlinks:nativestrict" SYMLINK_POS) + if(SYMLINK_POS GREATER -1) + set(ALLOW_BROKEN_SYMLINKS OFF) + endif() + elseif(CMAKE_SYSTEM_NAME STREQUAL "MSYS") + # The MSYS env variable behaves similar to the CYGWIN but has a + # different default behavior. If winsymlinks is set but not + # assigned one of the four supported values, the default is to + # *copy* the target to the symlink destination. This will fail + # if the target does not exist so broken symlinks cannot be + # allowed. + string(FIND "$ENV{MSYS}" "winsymlinks" SYMLINK_POS) + if(SYMLINK_POS GREATER -1) + string(FIND "$ENV{MSYS}" "winsymlinks:nativestrict" + SYMLINK_POS) + if(SYMLINK_POS GREATER -1) + set(ALLOW_BROKEN_SYMLINKS OFF) + endif() + else() + set(ALLOW_BROKEN_SYMLINKS OFF) + endif() + endif() + # Create symlinks in the build directory and then install them. # # The symlinks do not likely need any special extension since @@ -1189,13 +1245,25 @@ if(NOT MSVC AND HAVE_GETOPT_LONG) install(FILES "${CMAKE_CURRENT_BINARY_DIR}/${LINK}" DESTINATION "${CMAKE_INSTALL_BINDIR}" COMPONENT xz) - add_custom_target("${LINK}.1" ALL - "${CMAKE_COMMAND}" -E create_symlink "xz.1" "${LINK}.1" - BYPRODUCTS "${LINK}.1" - VERBATIM) - install(FILES "${CMAKE_CURRENT_BINARY_DIR}/${LINK}.1" - DESTINATION "${CMAKE_INSTALL_MANDIR}/man1" - COMPONENT xz) + + # Only create the man page symlinks if the symlinks can be + # created broken. The symlinks will not be valid until install + # so they cannot be created on these system environments. + if(ALLOW_BROKEN_SYMLINKS) + add_custom_target("${LINK}.1" ALL + "${CMAKE_COMMAND}" -E create_symlink "xz.1" "${LINK}.1" + BYPRODUCTS "${LINK}.1" + VERBATIM) + install(FILES "${CMAKE_CURRENT_BINARY_DIR}/${LINK}.1" + DESTINATION "${CMAKE_INSTALL_MANDIR}/man1" + COMPONENT xz) + else() + # Add the xz target as dependency when broken symlinks + # cannot be made. This ensures parallel builds do not fail + # since it will enforce the order of creating xz first, then + # the symlinks. + add_dependencies("${LINK}" xz) + endif() endforeach() endif() endif() |