windows: Declare strerror_s()

Older MinGW versions seem to miss this function declaration. Fixes build on
Travis using Ubuntu 12.04.

diff --git a/src/libstrongswan/utils/windows.h b/src/libstrongswan/utils/windows.h
index 053354f251093200340fb3df800e0251172dfff4..a06a89ebfa54c00c354b43a79a16375e2eb74dcc 100644 (file)
--- a/src/libstrongswan/utils/windows.h
+++ b/src/libstrongswan/utils/windows.h
@@ -361,6 +361,11 @@ ssize_t windows_send(int sockfd, const void *buf, size_t len, int flags);
 ssize_t windows_sendto(int sockfd, const void *buf, size_t len, int flags,
                                           const struct sockaddr *dest_addr, socklen_t addrlen);
 
+/**
+ * Declaration missing on older WinGW
+ */
+_CRTIMP errno_t strerror_s(char *buf, size_t size, int errnum);
+
 /**
  * strerror_s, but supporting POSIX compatiblity errno >= 100
  */