1 files changed, 75 insertions, 0 deletions
diff --git a/CMakeModules/UseCompat.cmake b/CMakeModules/UseCompat.cmake
new file mode 100644
index 0000000..c1befd7
--- /dev/null
+++ b/CMakeModules/UseCompat.cmake
@@ -0,0 +1,75 @@
+# - Use compat library providing various functions and macros that may be missing on some systems
+# Once done this will define
+#
+# compatsrc - sources to add to compilation
+#
+# Additionally, "compat.h" include directory is added and can be included.
+#
+# Author Michal Vasko <mvasko@cesnet.cz>
+#  Copyright (c) 2021 CESNET, z.s.p.o.
+#
+# This source code is licensed under BSD 3-Clause License (the "License").
+# You may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://opensource.org/licenses/BSD-3-Clause
+#
+include(CheckSymbolExists)
+include(CheckFunctionExists)
+include(CheckIncludeFile)
+include(TestBigEndian)
+if(POLICY CMP0075)
+    cmake_policy(SET CMP0075 NEW)
+endif()
+
+macro(USE_COMPAT)
+    # compatibility checks
+    set(CMAKE_REQUIRED_DEFINITIONS -D_POSIX_C_SOURCE=200809L)
+    list(APPEND CMAKE_REQUIRED_DEFINITIONS -D_GNU_SOURCE)
+    list(APPEND CMAKE_REQUIRED_DEFINITIONS -D__BSD_VISIBLE=1)
+    set(CMAKE_REQUIRED_LIBRARIES pthread)
+
+    check_symbol_exists(vdprintf "stdio.h;stdarg.h" HAVE_VDPRINTF)
+    check_symbol_exists(asprintf "stdio.h" HAVE_ASPRINTF)
+    check_symbol_exists(vasprintf "stdio.h" HAVE_VASPRINTF)
+    check_symbol_exists(getline "stdio.h" HAVE_GETLINE)
+
+    check_symbol_exists(strndup "string.h" HAVE_STRNDUP)
+    check_symbol_exists(strnstr "string.h" HAVE_STRNSTR)
+    check_symbol_exists(strdupa "string.h" HAVE_STRDUPA)
+    check_symbol_exists(strchrnul "string.h" HAVE_STRCHRNUL)
+
+    check_symbol_exists(get_current_dir_name "unistd.h" HAVE_GET_CURRENT_DIR_NAME)
+
+    check_function_exists(pthread_mutex_timedlock HAVE_PTHREAD_MUTEX_TIMEDLOCK)
+
+    TEST_BIG_ENDIAN(IS_BIG_ENDIAN)
+
+    check_include_file("stdatomic.h" HAVE_STDATOMIC)
+
+    include(CheckStructHasMember)
+    check_struct_has_member("struct tm" tm_gmtoff time.h HAVE_TM_GMTOFF)
+    check_symbol_exists(timezone time.h HAVE_TIME_H_TIMEZONE)
+
+    check_symbol_exists(realpath "stdlib.h" HAVE_REALPATH)
+    check_symbol_exists(localtime_r "time.h" HAVE_LOCALTIME_R)
+    check_symbol_exists(gmtime_r "time.h" HAVE_GMTIME_R)
+    check_symbol_exists(strptime "time.h" HAVE_STRPTIME)
+    check_symbol_exists(mmap "sys/mman.h" HAVE_MMAP)
+    check_symbol_exists(dirname "libgen.h" HAVE_DIRNAME)
+    check_symbol_exists(setenv "stdlib.h" HAVE_SETENV)
+
+    unset(CMAKE_REQUIRED_DEFINITIONS)
+    unset(CMAKE_REQUIRED_LIBRARIES)
+
+    # header and source file (adding the source directly allows for hiding its symbols)
+    configure_file(${PROJECT_SOURCE_DIR}/compat/compat.h.in ${PROJECT_BINARY_DIR}/compat/compat.h @ONLY)
+    include_directories(${PROJECT_BINARY_DIR}/compat)
+    set(compatsrc ${PROJECT_SOURCE_DIR}/compat/compat.c)
+    if(WIN32)
+        include_directories(${PROJECT_SOURCE_DIR}/compat/posix-shims)
+    endif()
+    if(NOT HAVE_STRPTIME)
+        set(compatsrc ${compatsrc} ${PROJECT_SOURCE_DIR}/compat/strptime.c)
+    endif()
+endmacro()