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Date: Wed, 27 Mar 2013 15:21:37 +0800
From: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
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Subject: Re: [Qemu-devel] [PATCH 1/2] char: introduce a blocking version of
 qemu_chr_fe_write
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Anthony Liguori <aliguori@us.ibm.com>, qemu-devel@nongnu.org

于 2013-3-26 23:21, Peter Maydell 写道:
> On 26 March 2013 15:11, Anthony Liguori <aliguori@us.ibm.com> wrote:
>> +int qemu_chr_fe_write_all(CharDriverState *s, const uint8_t *buf, int len)
>> +{
>> +    int offset = 0;
>> +    int res;
>> +
>> +    while (offset < len) {
>> +        do {
>> +            res = s->chr_write(s, buf + offset, len - offset);
>> +            if (res == -1 && errno == EAGAIN) {
>> +                g_usleep(100);
>> +            }
>> +        } while (res == -1 && errno == EAGAIN);
>
>     for (;;) {
>         res = s->chr_write(s, buf + offset, len - offset);
>         if (!(res == -1 && errno == EAGAIN)) {
>             break;
>         }
>         g_usleep(100);
>     }
>
> would avoid the duplication of the retry condition.
>
> -- PMM
>
I think adjust like following make code easier to read:

     while (offset < len) {
         res = s->chr_write(s, buf + offset, len - offset);
         if (res == -1 && errno == EAGAIN) {
                 g_usleep(100)
                 continue;
         }
         .....
     }
-- 
Best Regards

Wenchao Xia