Always use check_symbol_exists instead of check_function_exists.

CMakeLists.txt

@@ -210,13 +210,18 @@ CARES_EXTRAINCLUDE_IFSET (HAVE_SYS_TYPES_H    sys/types.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_ARPA_INET_H    arpa/inet.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_ARPA_NAMESER_H arpa/nameser.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_NETDB_H        netdb.h)
+CARES_EXTRAINCLUDE_IFSET (HAVE_NET_IF_H       net/if.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_NETINET_IN_H   netinet/in.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_NETINET_TCP_H  netinet/tcp.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_SIGNAL_H       signal.h)
+CARES_EXTRAINCLUDE_IFSET (HAVE_STDLIB_H       stdlib.h)
+CARES_EXTRAINCLUDE_IFSET (HAVE_STRING_H       string.h)
+CARES_EXTRAINCLUDE_IFSET (HAVE_STRINGS_H      strings.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_SYS_IOCTL_H    sys/ioctl.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_SYS_SELECT_H   sys/select.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_SYS_SOCKET_H   sys/socket.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_SYS_TIME_H     sys/time.h)
+CARES_EXTRAINCLUDE_IFSET (HAVE_SYS_UIO_H      sys/uio.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_TIME_H         time.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_FCNTL_H        fcntl.h)
 CARES_EXTRAINCLUDE_IFSET (HAVE_UNISTD_H       unistd.h)
@@ -283,59 +288,45 @@ CHECK_STRUCT_HAS_MEMBER("struct sockaddr_in6" sin6_scope_id "${CMAKE_EXTRA_INCLU
 CHECK_C_SOURCE_COMPILES ("int main() { int n=1234LL; return 0; }" HAVE_LL)
 
 
-# NOTE: CHECK_FUNCTION_EXISTS appears to be broken on 32bit Windows with VS2005
-#       at least.  It does not appear to honor CMAKE_REQUIRED_LIBRARIES for some
-#       reason so does not find functions that are not in the standard C library.
-#       For this reason, we are going to at least just make sure it is in the
-#       headers by using CHECK_SYMBOL_EXISTS.  But we wrap it in a Macro to allow
-#       it to work on other systems
-MACRO (CARES_FUNCTION_EXISTS func var)
-	IF (WIN32 AND MSVC)
-		CHECK_SYMBOL_EXISTS("${func}" "${CMAKE_EXTRA_INCLUDE_FILES}" "${var}")
-	ELSE ()
-		CHECK_FUNCTION_EXISTS("${func}" "${var}")
-	ENDIF ()
-ENDMACRO ()
-
-CARES_FUNCTION_EXISTS (bitncmp         HAVE_BITNCMP)
-CARES_FUNCTION_EXISTS (closesocket     HAVE_CLOSESOCKET)
-CARES_FUNCTION_EXISTS (CloseSocket     HAVE_CLOSESOCKET_CAMEL)
-CARES_FUNCTION_EXISTS (connect         HAVE_CONNECT)
-CARES_FUNCTION_EXISTS (fcntl           HAVE_FCNTL)
-CARES_FUNCTION_EXISTS (freeaddrinfo    HAVE_FREEADDRINFO)
-CARES_FUNCTION_EXISTS (getaddrinfo     HAVE_GETADDRINFO)
-CARES_FUNCTION_EXISTS (getenv          HAVE_GETENV)
-CARES_FUNCTION_EXISTS (gethostbyaddr   HAVE_GETHOSTBYADDR)
-CARES_FUNCTION_EXISTS (gethostbyname   HAVE_GETHOSTBYNAME)
-CARES_FUNCTION_EXISTS (gethostname     HAVE_GETHOSTNAME)
-CARES_FUNCTION_EXISTS (getnameinfo     HAVE_GETNAMEINFO)
-CARES_FUNCTION_EXISTS (getservbyport_r HAVE_GETSERVBYPORT_R)
-CARES_FUNCTION_EXISTS (gettimeofday    HAVE_GETTIMEOFDAY)
-CARES_FUNCTION_EXISTS (if_indextoname  HAVE_IF_INDEXTONAME)
-CARES_FUNCTION_EXISTS (inet_net_pton   HAVE_INET_NET_PTON)
+CHECK_SYMBOL_EXISTS (bitncmp         "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_BITNCMP)
+CHECK_SYMBOL_EXISTS (closesocket     "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_CLOSESOCKET)
+CHECK_SYMBOL_EXISTS (CloseSocket     "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_CLOSESOCKET_CAMEL)
+CHECK_SYMBOL_EXISTS (connect         "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_CONNECT)
+CHECK_SYMBOL_EXISTS (fcntl           "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_FCNTL)
+CHECK_SYMBOL_EXISTS (freeaddrinfo    "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_FREEADDRINFO)
+CHECK_SYMBOL_EXISTS (getaddrinfo     "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_GETADDRINFO)
+CHECK_SYMBOL_EXISTS (getenv          "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_GETENV)
+CHECK_SYMBOL_EXISTS (gethostbyaddr   "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_GETHOSTBYADDR)
+CHECK_SYMBOL_EXISTS (gethostbyname   "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_GETHOSTBYNAME)
+CHECK_SYMBOL_EXISTS (gethostname     "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_GETHOSTNAME)
+CHECK_SYMBOL_EXISTS (getnameinfo     "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_GETNAMEINFO)
+CHECK_SYMBOL_EXISTS (getservbyport_r "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_GETSERVBYPORT_R)
+CHECK_SYMBOL_EXISTS (gettimeofday    "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_GETTIMEOFDAY)
+CHECK_SYMBOL_EXISTS (if_indextoname  "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_IF_INDEXTONAME)
+CHECK_SYMBOL_EXISTS (inet_net_pton   "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_INET_NET_PTON)
 IF (NOT WIN32)
-	# Disabled on windows.  CARES_FUNCTION_EXISTS will say they exist, but
-	# it doesn't appear as though proper headers really exist for these functions
-	# as there are prototype warnings during the build.
-	CARES_FUNCTION_EXISTS (inet_ntop       HAVE_INET_NTOP)
-	CARES_FUNCTION_EXISTS (inet_pton       HAVE_INET_PTON)
+	# Disabled on Windows, because these functions are only really supported on Windows
+	# Vista or newer (_WIN32_WINNT >= 0x0600). Older versions of Windows may provide
+	# them as experimental non-working features, so we have to disable them manually.
+	CHECK_SYMBOL_EXISTS (inet_ntop       "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_INET_NTOP)
+	CHECK_SYMBOL_EXISTS (inet_pton       "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_INET_PTON)
 ENDIF ()
-CARES_FUNCTION_EXISTS (ioctl           HAVE_IOCTL)
-CARES_FUNCTION_EXISTS (ioctlsocket     HAVE_IOCTLSOCKET)
-CARES_FUNCTION_EXISTS (IoctlSocket     HAVE_IOCTLSOCKET_CAMEL)
-CARES_FUNCTION_EXISTS (recv            HAVE_RECV)
-CARES_FUNCTION_EXISTS (recvfrom        HAVE_RECVFROM)
-CARES_FUNCTION_EXISTS (send            HAVE_SEND)
-CARES_FUNCTION_EXISTS (setsockopt      HAVE_SETSOCKOPT)
-CARES_FUNCTION_EXISTS (socket          HAVE_SOCKET)
-CARES_FUNCTION_EXISTS (strcasecmp      HAVE_STRCASECMP)
-CARES_FUNCTION_EXISTS (strcmpi         HAVE_STRCMPI)
-CARES_FUNCTION_EXISTS (strdup          HAVE_STRDUP)
-CARES_FUNCTION_EXISTS (stricmp         HAVE_STRICMP)
-CARES_FUNCTION_EXISTS (strncasecmp     HAVE_STRNCASECMP)
-CARES_FUNCTION_EXISTS (strncmpi        HAVE_STRNCMPI)
-CARES_FUNCTION_EXISTS (strnicmp        HAVE_STRNICMP)
-CARES_FUNCTION_EXISTS (writev          HAVE_WRITEV)
+CHECK_SYMBOL_EXISTS (ioctl           "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_IOCTL)
+CHECK_SYMBOL_EXISTS (ioctlsocket     "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_IOCTLSOCKET)
+CHECK_SYMBOL_EXISTS (IoctlSocket     "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_IOCTLSOCKET_CAMEL)
+CHECK_SYMBOL_EXISTS (recv            "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_RECV)
+CHECK_SYMBOL_EXISTS (recvfrom        "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_RECVFROM)
+CHECK_SYMBOL_EXISTS (send            "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_SEND)
+CHECK_SYMBOL_EXISTS (setsockopt      "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_SETSOCKOPT)
+CHECK_SYMBOL_EXISTS (socket          "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_SOCKET)
+CHECK_SYMBOL_EXISTS (strcasecmp      "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_STRCASECMP)
+CHECK_SYMBOL_EXISTS (strcmpi         "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_STRCMPI)
+CHECK_SYMBOL_EXISTS (strdup          "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_STRDUP)
+CHECK_SYMBOL_EXISTS (stricmp         "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_STRICMP)
+CHECK_SYMBOL_EXISTS (strncasecmp     "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_STRNCASECMP)
+CHECK_SYMBOL_EXISTS (strncmpi        "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_STRNCMPI)
+CHECK_SYMBOL_EXISTS (strnicmp        "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_STRNICMP)
+CHECK_SYMBOL_EXISTS (writev          "${CMAKE_EXTRA_INCLUDE_FILES}" HAVE_WRITEV)
 
 # Unset temporary data
 SET (CMAKE_EXTRA_INCLUDE_FILES)