src: os2: move gai_strerror() to compat

This fixes the following linkage error.

-----
  CCLD     libhttps_plugin.la
weakld: error: Unresolved symbol (UNDEF) '_gai_strerror'.
weakld: info: The symbol is referenced by:
    P:\tmp\ldconv_libvlc_http_la-transport_o_64fd5671f455159d80.obj
Ignoring unresolved externals reported from weak prelinker.
Error! E2028: _gai_strerror is an undefined reference
file P:/tmp\ldconv_libvlc_http_la-transport_o_64fd5671f455159d80.obj(ldconv_libvlc_http_la-transport_o_64fd5671f455159d80.obj): undefined symbol _gai_strerror
make.exe[4]: *** [libhttps_plugin.la] Error 1
-----
Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>

compat/gai_strerror.c

+/*****************************************************************************
+ * gai_strerror.c: gai_strerror() replacement function
+ *****************************************************************************
+ * Copyright (C) 2005 the VideoLAN team
+ * Copyright (C) 2002-2007 Rémi Denis-Courmont
+ * Copyright (C) 2011-2015 KO Myung-Hun
+ *
+ * Authors: KO Myung-Hun <komh@chollian.net>
+ *          Rémi Denis-Courmont <rem # videolan.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+/* GAI error codes. See include/vlc_network.h. */
+#ifndef EAI_BADFLAGS
+# define EAI_BADFLAGS -1
+#endif
+#ifndef EAI_NONAME
+# define EAI_NONAME -2
+#endif
+#ifndef EAI_AGAIN
+# define EAI_AGAIN -3
+#endif
+#ifndef EAI_FAIL
+# define EAI_FAIL -4
+#endif
+#ifndef EAI_NODATA
+# define EAI_NODATA -5
+#endif
+#ifndef EAI_FAMILY
+# define EAI_FAMILY -6
+#endif
+#ifndef EAI_SOCKTYPE
+# define EAI_SOCKTYPE -7
+#endif
+#ifndef EAI_SERVICE
+# define EAI_SERVICE -8
+#endif
+#ifndef EAI_ADDRFAMILY
+# define EAI_ADDRFAMILY -9
+#endif
+#ifndef EAI_MEMORY
+# define EAI_MEMORY -10
+#endif
+#ifndef EAI_OVERFLOW
+# define EAI_OVERFLOW -11
+#endif
+#ifndef EAI_SYSTEM
+# define EAI_SYSTEM -12
+#endif
+
+static const struct
+{
+    int        code;
+    const char msg[41];
+} gai_errlist[] =
+{
+    { 0,              "Error 0" },
+    { EAI_BADFLAGS,   "Invalid flag used" },
+    { EAI_NONAME,     "Host or service not found" },
+    { EAI_AGAIN,      "Temporary name service failure" },
+    { EAI_FAIL,       "Non-recoverable name service failure" },
+    { EAI_NODATA,     "No data for host name" },
+    { EAI_FAMILY,     "Unsupported address family" },
+    { EAI_SOCKTYPE,   "Unsupported socket type" },
+    { EAI_SERVICE,    "Incompatible service for socket type" },
+    { EAI_ADDRFAMILY, "Unavailable address family for host name" },
+    { EAI_MEMORY,     "Memory allocation failure" },
+    { EAI_OVERFLOW,   "Buffer overflow" },
+    { EAI_SYSTEM,     "System error" },
+    { 0,              "" },
+};
+
+static const char gai_unknownerr[] = "Unrecognized error number";
+
+/****************************************************************************
+ * Converts an EAI_* error code into human readable english text.
+ ****************************************************************************/
+const char *gai_strerror (int errnum)
+{
+    for (unsigned i = 0; *gai_errlist[i].msg; i++)
+        if (errnum == gai_errlist[i].code)
+            return gai_errlist[i].msg;
+
+    return gai_unknownerr;
+}

configure.ac

@@ -290,6 +290,7 @@ case "${host_os}" in
     SYS=os2
     LDFLAGS="${LDFLAGS} -Zomf -Zbin-files -Zargs-wild -Zhigh-mem"
     AC_LIBOBJ([freeaddrinfo])
+    AC_LIBOBJ([gai_strerror])
     ;;
   *)
     SYS="${host_os}"

src/os2/getaddrinfo.c

@@ -32,42 +32,6 @@
 
 #include <arpa/inet.h>
 
-static const struct
-{
-    int        code;
-    const char msg[41];
-} gai_errlist[] =
-{
-    { 0,              "Error 0" },
-    { EAI_BADFLAGS,   "Invalid flag used" },
-    { EAI_NONAME,     "Host or service not found" },
-    { EAI_AGAIN,      "Temporary name service failure" },
-    { EAI_FAIL,       "Non-recoverable name service failure" },
-    { EAI_NODATA,     "No data for host name" },
-    { EAI_FAMILY,     "Unsupported address family" },
-    { EAI_SOCKTYPE,   "Unsupported socket type" },
-    { EAI_SERVICE,    "Incompatible service for socket type" },
-    { EAI_ADDRFAMILY, "Unavailable address family for host name" },
-    { EAI_MEMORY,     "Memory allocation failure" },
-    { EAI_OVERFLOW,   "Buffer overflow" },
-    { EAI_SYSTEM,     "System error" },
-    { 0,              "" },
-};
-
-static const char gai_unknownerr[] = "Unrecognized error number";
-
-/****************************************************************************
- * Converts an EAI_* error code into human readable english text.
- ****************************************************************************/
-const char *gai_strerror (int errnum)
-{
-    for (unsigned i = 0; *gai_errlist[i].msg; i++)
-        if (errnum == gai_errlist[i].code)
-            return gai_errlist[i].msg;
-
-    return gai_unknownerr;
-}
-
 #define _NI_MASK (NI_NUMERICHOST|NI_NUMERICSERV|NI_NOFQDN|NI_NAMEREQD|\
                   NI_DGRAM)
 /*