[Olsr-dev] [PATCH v1 1/2] android: fix type punning warnings on IN6_IS_ADDR_V4MAPPED

[Ferry Huberts]

On 22-10-12 17:28, Hans-Christoph Steiner wrote:
>
>
> On 10/22/2012 04:59 AM, Ferry Huberts wrote:
>>
>>
>> On 19-10-12 18:12, Hans-Christoph Steiner wrote:
>>>
>>> Android is not GNU and its not UNIX, so including a header from GNU seems like
>>> a bad idea.  Android does not use GNU libc nor does it use BSD libc.  It uses
>>> bionic libc.  Yes, Android uses the Linux kernel, but these headers are not
>>> from the Linux kernel, they are related to libc.
>>>
>>> I think we'll have to do something ugly anyhow, unfortunately.  Maybe for
>>> android, the v6 part of p->prefix.v6 will need to be defined the same way that
>>> its done in the Android in6.h header and wrapped in a #ifdef __ANDROID__ #else
>>>
>>
>> I see no problem in doing it this way.
>> However, if you want it different, then can you please show us that change/patch?
>>
>> We're almost at the point of zero warnings after we fix this one, so why stop
>> now?
>
>
> Because preventing bugs is far more important than compiler warnings.
> Compiler warnings are a useful tool, but never a goal.  Using the wrong
> headers is a recipe for disaster, especially when the whole problem you are
> trying to solve comes from differences in GNU libc and Android's bionic libc.
>


I'll ask again: if you want it different, then can you please show us 
that change/patch?

You appointed yourself olsrd Android maintainer, so please fix the 
warnings. Fix them in a way that is acceptable to you, and to us please.

> .hc
>
>
>>
>>
>>> .hc
>>>
>>> On 10/19/2012 12:05 PM, Ferry Huberts wrote:
>>>> From: Ferry Huberts <(spam-protected)>
>>>>
>>>> Signed-off-by: Ferry Huberts <(spam-protected)>
>>>> ---
>>>>    android/linux/olsr_netinet_in.h | 52
>>>> +++++++++++++++++++++++++++++++++++++++++
>>>>    src/ipcalc.h                    |  4 ++++
>>>>    2 files changed, 56 insertions(+)
>>>>    create mode 100644 android/linux/olsr_netinet_in.h
>>>>
>>>> diff --git a/android/linux/olsr_netinet_in.h b/android/linux/olsr_netinet_in.h
>>>> new file mode 100644
>>>> index 0000000..7500c80
>>>> --- /dev/null
>>>> +++ b/android/linux/olsr_netinet_in.h
>>>> @@ -0,0 +1,52 @@
>>>> +/* Copyright (C) 1991-2001, 2003, 2004, 2006, 2007, 2008, 2011
>>>> +   Free Software Foundation, Inc.
>>>> +   This file is part of the GNU C Library.
>>>> +
>>>> +   The GNU C Library 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.
>>>> +
>>>> +   The GNU C Library 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 the GNU C Library; if not, write to the Free
>>>> +   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
>>>> +   02111-1307 USA.
>>>> +
>>>> +
>>>> +   This is a stripped copy of netinet/in.h that includes only the
>>>> +   IN6_IS_ADDR_V4MAPPED define. It is used to fix warnings on the
>>>> +   Android build.
>>>> +*/
>>>> +
>>>> +#ifndef    _OLSR_NETINET_IN_H
>>>> +#define    _OLSR_NETINET_IN_H    1
>>>> +
>>>> +#ifdef IN6_IS_ADDR_V4MAPPED
>>>> +  #undef IN6_IS_ADDR_V4MAPPED
>>>> +#endif
>>>> +
>>>> +
>>>> +#ifdef __GNUC__
>>>> +
>>>> +# define IN6_IS_ADDR_V4MAPPED(a) \
>>>> +  (__extension__                                  \
>>>> +   ({ __const struct in6_addr *__a = (__const struct in6_addr *)
>>>> (a);          \
>>>> +      __a->s6_addr32[0] == 0                              \
>>>> +      && __a->s6_addr32[1] == 0                              \
>>>> +      && __a->s6_addr32[2] == htonl (0xffff); }))
>>>> +
>>>> +#else
>>>> +
>>>> +# define IN6_IS_ADDR_V4MAPPED(a) \
>>>> +    ((((__const uint32_t *) (a))[0] == 0)                      \
>>>> +     && (((__const uint32_t *) (a))[1] == 0)                  \
>>>> +     && (((__const uint32_t *) (a))[2] == htonl (0xffff)))
>>>> +
>>>> +#endif
>>>> +
>>>> +#endif    /* _OLSR_NETINET_IN_H */
>>>> diff --git a/src/ipcalc.h b/src/ipcalc.h
>>>> index 30b8068..4dde3f4 100644
>>>> --- a/src/ipcalc.h
>>>> +++ b/src/ipcalc.h
>>>> @@ -49,6 +49,10 @@
>>>>    #include <arpa/inet.h>
>>>>    #include <netinet/in.h>
>>>>
>>>> +#ifdef __ANDROID__
>>>> +  #include <linux/olsr_netinet_in.h>
>>>> +#endif
>>>> +
>>>>    extern const struct olsr_ip_prefix ipv4_internet_route;
>>>>    extern const struct olsr_ip_prefix ipv6_mappedv4_route;
>>>>    extern const struct olsr_ip_prefix ipv6_internet_route;
>>>>
>>

-- 
Ferry Huberts