Re: [Qemu-devel] [RFC 03/12] Add socket_writev_buffer function

[Paolo Bonzini]

Il 21/03/2013 10:47, Orit Wasserman ha scritto:
> On 03/21/2013 11:18 AM, Paolo Bonzini wrote:
>> Il 21/03/2013 10:09, Orit Wasserman ha scritto:
>>> Signed-off-by: Orit Wasserman <address@hidden>
>>> ---
>>>  savevm.c | 14 ++++++++++++++
>>>  1 file changed, 14 insertions(+)
>>>
>>> diff --git a/savevm.c b/savevm.c
>>> index 35c8d1e..41dc87f 100644
>>> --- a/savevm.c
>>> +++ b/savevm.c
>>> @@ -39,6 +39,7 @@
>>>  #include "qmp-commands.h"
>>>  #include "trace.h"
>>>  #include "qemu/bitops.h"
>>> +#include "qemu/iov.h"
>>>  
>>>  #define SELF_ANNOUNCE_ROUNDS 5
>>>  
>>> @@ -171,6 +172,18 @@ static void coroutine_fn yield_until_fd_readable(int 
>>> fd)
>>>      qemu_coroutine_yield();
>>>  }
>>>  
>>> +static int socket_writev_buffer(void *opaque, struct iovec *iov, int 
>>> iovcnt)
>>> +{
>>> +    QEMUFileSocket *s = opaque;
>>> +    ssize_t len;
>>> +
>>> +    len = iov_writev(s->fd, iov, iovcnt);
>>> +    if (len < iov_size(iov, iovcnt)) {
>>> +        len = -socket_error();
>>> +    }
>>> +    return len;
>>> +}
>>
>> This doesn't work on Windows, you need iov_send:
>>
>> ssize_t iov_send(int sockfd, struct iovec *iov, unsigned iov_cnt,
>>                  size_t offset, size_t bytes);
>>
> iov_writev is implemented like iov_send the only difference is that it uses 
> writev and not sendmsg
> so it can work on files.
> So in windows it will use send.

Yes, I would prefer to use send since here we know it's a socket.  See
the general review, I don't think iov_writev is needed.

Paolo

> Orit
>> Paolo
>>
>> +
>>>  static int socket_get_fd(void *opaque)
>>>  {
>>>      QEMUFileSocket *s = opaque;
>>> @@ -387,6 +400,7 @@ static const QEMUFileOps socket_read_ops = {
>>>  static const QEMUFileOps socket_write_ops = {
>>>      .get_fd =     socket_get_fd,
>>>      .put_buffer = socket_put_buffer,
>>> +    .writev_buffer = socket_writev_buffer,
>>>      .close =      socket_close
>>>  };
>>>  
>>>
>>
>