#
# Copyright (c) 2018 Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
#

# FreeBSD has ELAST which tells us what the highest errno it define is
check_symbol_exists(ELAST "errno.h" HAVE_ELAST)

if(HAVE_ELAST)
	set(LAST_ERRNO "ELAST")
else()
	set(LAST_ERRNO "256")
endif()
message("-- Assuming largest errno is less than or equal to ${LAST_ERRNO}")

set(NEXT_ERRNO 1)

macro(find_errno errno)
	check_symbol_exists(${errno} "errno.h" HAVE_${errno})
	if(NOT HAVE_${errno})
		set(JEFFPC_ERRNO_${errno} "(${LAST_ERRNO} + ${NEXT_ERRNO})")
		math(EXPR NEXT_ERRNO "(${NEXT_ERRNO} + 1)")
	endif()
endmacro()

find_errno(ECKSUM)
find_errno(ENOTUNIQ)
