xmppipe_roomname: use define for hostname

src/xmppipe.c

@@ -190,7 +190,7 @@ main(int argc, char **argv)
         state->room = xmppipe_roomname("stdout");
 
     if (state->resource == NULL)
-        state->resource = xmppipe_strdup("xmppipe");
+        state->resource = xmppipe_strdup(XMPPIPE_RESOURCE);
 
     if (strchr(state->room, '@')) {
         state->out = xmppipe_strdup(state->room);

src/xmppipe.h

@@ -22,6 +22,7 @@
 #include <strophe.h>
 
 #define XMPPIPE_VERSION "0.8.0"
+#define XMPPIPE_RESOURCE "xmppipe"
 
 #define XMPPIPE_STREQ(a,b)      (strcmp((a),(b)) == 0)
 #define XMPPIPE_STRNEQ(a,b)     (strcmp((a),(b)) != 0)

src/xmppipe_util.c

@@ -1,4 +1,4 @@
-/* Copyright (c) 2015, Michael Santos <michael.santos@gmail.com>
+/* Copyright (c) 2015-2017, Michael Santos <michael.santos@gmail.com>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -204,7 +204,7 @@ xmppipe_roomname(char *label)
 
     buf = xmppipe_malloc(len);
     if (gethostname(name, sizeof(name)) < 0) {
-        (void)memcpy(name, "xmppipe", sizeof(name)-1);
+        (void)snprintf(name, sizeof(name)-1, "%s", XMPPIPE_RESOURCE);
     }
     name[sizeof(name)-1] = '\0';