void *mem;  PRInt32 len = strlen(s) + 1; PL_ARENA_ALLOCATE(mem, arena, len); if (mem) memcpy(mem, s, len); return NS_STATIC_CAST(char *, mem);
return ArenaStrndup(s, strlen(s), arena);
ArenaStrdup(const char *s, PLArenaPool *arena){    void *mem;    // Include trailing null in the len    PRInt32 len = strlen(s) + 1;    PL_ARENA_ALLOCATE(mem, arena, len);    if (mem)        memcpy(mem, s, len);    return NS_STATIC_CAST(char *, mem);}