Import all system definitions of errno including their string representations, then layer our error definitions on top of that

CMakeLists.txt

@@ -7,10 +7,27 @@ include(CMakePackageConfigHelpers)
 set(AKERR_USE_STDLIB 1 CACHE BOOL "Use the C standard library")
 set(akerror_install_cmakedir "${CMAKE_INSTALL_LIBDIR}/cmake/akerror")
 
+set(SCRIPT ${CMAKE_SOURCE_DIR}/scripts/generrno.sh)
+set(INFILE ${CMAKE_SOURCE_DIR}/include/akerror.tmpl.h)
+set(OUTFILES ${CMAKE_SOURCE_DIR}/src/errno.c ${CMAKE_SOURCE_DIR}/include/akerror.h)
+add_custom_command(
+  OUTPUT ${OUTFILES}
+  COMMAND ${CMAKE_COMMAND} -E make_directory ${CMAKE_SOURCE_DIR}
+  COMMAND /usr/bin/env bash ${SCRIPT} ${CMAKE_SOURCE_DIR}
+  DEPENDS ${SCRIPT} ${INFILE}
+  VERBATIM
+)
+
+set_source_files_properties(src/errno.c PROPERTIES GENERATED TRUE)
+
+add_custom_target(generrno DEPENDS src/errno.c)
+
 find_package(PkgConfig REQUIRED)
 add_library(akerror STATIC
-    src/error.c
+  src/error.c
+  src/errno.c
 )
+add_dependencies(akerror generrno)
 
 target_compile_definitions(akerror
     PUBLIC AKERR_USE_STDLIB=${AKERR_USE_STDLIB}