restore #undef'ed macro values after we're done

some programs that define these miss them if removed

push_macro and pop_macro pragmas allegedly well supported
by gcc, clang and msvc

--- a/include/fortify/poll.h
+++ b/include/fortify/poll.h
@@ -29,6 +29,7 @@ __extension__
 extern "C" {
 #endif
 
+#pragma push_macro("poll")
 #undef poll
 
 _FORTIFY_FN(poll) int poll(struct pollfd * _FORTIFY_POS0 __f, nfds_t __n, int __s)
@@ -40,6 +41,8 @@ _FORTIFY_FN(poll) int poll(struct pollfd * _FORTIFY_POS0 __f, nfds_t __n, int __
 	return __orig_poll(__f, __n, __s);
 }
 
+#pragma pop_macro("poll")
+
 #ifdef __cplusplus
 }
 #endif
--- a/include/fortify/stdio.h
+++ b/include/fortify/stdio.h
@@ -29,12 +29,19 @@ __extension__
 extern "C" {
 #endif
 
+#pragma push_macro("fgets")
 #undef fgets
+#pragma push_macro("fread")
 #undef fread
+#pragma push_macro("fwrite")
 #undef fwrite
+#pragma push_macro("vsprintf")
 #undef vsprintf
+#pragma push_macro("vsnprintf")
 #undef vsnprintf
+#pragma push_macro("snprintf")
 #undef snprintf
+#pragma push_macro("sprintf")
 #undef sprintf
 
 _FORTIFY_FN(fgets) char *fgets(char * _FORTIFY_POS0 __s, int __n, FILE *__f)
@@ -140,6 +147,14 @@ _FORTIFY_FN(sprintf) int sprintf(char *__s, const char *__f, ...)
 #endif /* __has_builtin(__builtin_va_arg_pack) */
 #endif /* defined(__has_builtin) */
 
+#pragma pop_macro("fgets")
+#pragma pop_macro("fread")
+#pragma pop_macro("fwrite")
+#pragma pop_macro("vsprintf")
+#pragma pop_macro("vsnprintf")
+#pragma pop_macro("snprintf")
+#pragma pop_macro("sprintf")
+
 #ifdef __cplusplus
 }
 #endif
--- a/include/fortify/stdlib.h
+++ b/include/fortify/stdlib.h
@@ -38,7 +38,10 @@ extern "C" {
 
 /* FIXME clang */
 #if (defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) || defined(_BSD_SOURCE)) && !defined(__clang__)
+
+#pragma push_macro("realpath")
 #undef realpath
+
 _FORTIFY_FN(realpath) char *realpath(const char *__p, char *__r)
 {
 #ifndef PATH_MAX
@@ -60,6 +63,9 @@ _FORTIFY_FN(realpath) char *realpath(const char *__p, char *__r)
 	return __orig_realpath(__p, __r);
 #endif
 }
+
+#pragma pop_macro("realpath")
+
 #endif
 
 #ifdef __cplusplus
--- a/include/fortify/string.h
+++ b/include/fortify/string.h
@@ -29,12 +29,19 @@ __extension__
 extern "C" {
 #endif
 
+#pragma push_macro("memcpy")
 #undef memcpy
+#pragma push_macro("memmove")
 #undef memmove
+#pragma push_macro("memset")
 #undef memset
+#pragma push_macro("strcat")
 #undef strcat
+#pragma push_macro("strcpy")
 #undef strcpy
+#pragma push_macro("strncat")
 #undef strncat
+#pragma push_macro("strncpy")
 #undef strncpy
 
 _FORTIFY_FN(memcpy) void *memcpy(void * _FORTIFY_POS0 __od,
@@ -183,6 +190,14 @@ _FORTIFY_FN(strlcpy) size_t strlcpy(char * _FORTIFY_POS0 __d,
 }
 #endif
 
+#pragma pop_macro("memcpy")
+#pragma pop_macro("memmove")
+#pragma pop_macro("memset")
+#pragma pop_macro("strcat")
+#pragma pop_macro("strcpy")
+#pragma pop_macro("strncat")
+#pragma pop_macro("strncpy")
+
 #ifdef __cplusplus
 }
 #endif
--- a/include/fortify/strings.h
+++ b/include/fortify/strings.h
@@ -29,8 +29,12 @@ extern "C" {
 #if defined(_GNU_SOURCE) || defined(_BSD_SOURCE) || defined(_POSIX_SOURCE) \
  || (defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE+0 < 200809L) \
  || (defined(_XOPEN_SOURCE) && _XOPEN_SOURCE+0 < 700)
+
+#pragma push_macro("bcopy")
 #undef bcopy
+#pragma push_macro("bzero")
 #undef bzero
+
 _FORTIFY_FN(bcopy) void bcopy(const void * _FORTIFY_POS0 __s,
                               void * _FORTIFY_POS0 __d, size_t __n)
 {
@@ -52,6 +56,9 @@ _FORTIFY_FN(bzero) void bzero(void * _FORTIFY_POS0 __s, size_t __n)
 }
 #endif
 
+#pragma pop_macro("bcopy")
+#pragma pop_macro("bzero")
+
 #ifdef __cplusplus
 }
 #endif
--- a/include/fortify/sys/socket.h
+++ b/include/fortify/sys/socket.h
@@ -29,9 +29,13 @@ __extension__
 extern "C" {
 #endif
 
+#pragma push_macro("recv")
 #undef recv
+#pragma push_macro("recvfrom")
 #undef recvfrom
+#pragma push_macro("send")
 #undef send
+#pragma push_macro("sendto")
 #undef sendto
 
 _FORTIFY_FN(recv) ssize_t recv(int __f, void * _FORTIFY_POS0 __s, size_t __n,
@@ -76,6 +80,11 @@ _FORTIFY_FN(sendto) ssize_t sendto(int __f, const void * _FORTIFY_POS0 __s,
 	return __orig_sendto(__f, __s, __n, __fl, __a, __l);
 }
 
+#pragma push_macro("recv")
+#pragma push_macro("recvfrom")
+#pragma push_macro("send")
+#pragma push_macro("sendto")
+
 #ifdef __cplusplus
 }
 #endif
--- a/include/fortify/unistd.h
+++ b/include/fortify/unistd.h
@@ -29,16 +29,27 @@ __extension__
 extern "C" {
 #endif
 
+#pragma push_macro("confstr")
 #undef confstr
+#pragma push_macro("getcwd")
 #undef getcwd
+#pragma push_macro("getgroups")
 #undef getgroups
+#pragma push_macro("gethostname")
 #undef gethostname
+#pragma push_macro("getlogin_r")
 #undef getlogin_r
+#pragma push_macro("pread")
 #undef pread
+#pragma push_macro("read")
 #undef read
+#pragma push_macro("readlink")
 #undef readlink
+#pragma push_macro("readlinkat")
 #undef readlinkat
+#pragma push_macro("ttyname_r")
 #undef ttyname_r
+#pragma push_macro("write")
 #undef write
 
 _FORTIFY_FN(confstr) size_t confstr(int __n, char * _FORTIFY_POS0 __s, size_t __l)
@@ -158,6 +169,18 @@ _FORTIFY_FN(write) ssize_t write(int __f, const void * _FORTIFY_POS0 __s,
 	return __orig_write(__f, __s, __n);
 }
 
+#pragma pop_macro("confstr")
+#pragma pop_macro("getcwd")
+#pragma pop_macro("getgroups")
+#pragma pop_macro("gethostname")
+#pragma pop_macro("getlogin_r")
+#pragma pop_macro("pread")
+#pragma pop_macro("read")
+#pragma pop_macro("readlink")
+#pragma pop_macro("readlinkat")
+#pragma pop_macro("ttyname_r")
+#pragma pop_macro("write")
+
 #ifdef __cplusplus
 }
 #endif
--- a/include/fortify/wchar.h
+++ b/include/fortify/wchar.h
@@ -43,19 +43,33 @@ __extension__
 extern "C" {
 #endif
 
+#pragma push_macro("fgetws")
 #undef fgetws
+#pragma push_macro("mbsrtowcs")
 #undef mbsrtowcs
+#pragma push_macro("mbstowcs")
 #undef mbstowcs
+#pragma push_macro("wcrtomb")
 #undef wcrtomb
+#pragma push_macro("wcscat")
 #undef wcscat
+#pragma push_macro("wcscpy")
 #undef wcscpy
+#pragma push_macro("wcsncat")
 #undef wcsncat
+#pragma push_macro("wcsncpy")
 #undef wcsncpy
+#pragma push_macro("wcsrtombs")
 #undef wcsrtombs
+#pragma push_macro("wcstombs")
 #undef wcstombs
+#pragma push_macro("wctomb")
 #undef wctomb
+#pragma push_macro("wmemcpy")
 #undef wmemcpy
+#pragma push_macro("wmemmove")
 #undef wmemmove
+#pragma push_macro("wmemset")
 #undef wmemset
 
 _FORTIFY_FN(fgetws) wchar_t *fgetws(wchar_t * _FORTIFY_POS0 __s,
@@ -269,6 +283,21 @@ _FORTIFY_FN(wmemset) wchar_t *wmemset(wchar_t * _FORTIFY_POS0 __s,
 	return __orig_wmemset(__s, __c, __n);
 }
 
+#pragma pop_macro("fgetws")
+#pragma pop_macro("mbsrtowcs")
+#pragma pop_macro("mbstowcs")
+#pragma pop_macro("wcrtomb")
+#pragma pop_macro("wcscat")
+#pragma pop_macro("wcscpy")
+#pragma pop_macro("wcsncat")
+#pragma pop_macro("wcsncpy")
+#pragma pop_macro("wcsrtombs")
+#pragma pop_macro("wcstombs")
+#pragma pop_macro("wctomb")
+#pragma pop_macro("wmemcpy")
+#pragma pop_macro("wmemmove")
+#pragma pop_macro("wmemset")
+
 #ifdef __cplusplus
 }
 #endif