Hi
On Tue, Sep 22, 2015 at 4:01 PM, Claudio Fontana
<claudio.font...@huawei.com> wrote:
> On 15.09.2015 18:07, marcandre.lur...@redhat.com wrote:
>> From: Marc-André Lureau <marcandre.lur...@redhat.com>
>>
>> Make a new function fifo_update_and_get() that can be reused by other
>> functions (in next commits).
>>
>> Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com>
>> ---
>> hw/misc/ivshmem.c | 59
>> ++++++++++++++++++++++++++++++++++++-------------------
>> 1 file changed, 39 insertions(+), 20 deletions(-)
>>
>> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
>> index 2162d02..dd15f0e 100644
>> --- a/hw/misc/ivshmem.c
>> +++ b/hw/misc/ivshmem.c
>> @@ -441,6 +441,42 @@ static int increase_dynamic_storage(IVShmemState *s,
>> int new_min_size)
>> return 0;
>> }
>>
>> +static bool fifo_update_and_get(IVShmemState *s, const uint8_t *buf, int
>> size,
>> + void *data, size_t len)
>> +{
>> + const uint8_t *p;
>> + uint32_t num;
>> +
>> + assert(len <= sizeof(long)); /* limitation of the fifo */
>> + if (fifo8_is_empty(&s->incoming_fifo) && size == len) {
>> + memcpy(data, buf, size);
>> + return true;
>> + }
>> +
>> + IVSHMEM_DPRINTF("short read of %d bytes\n", size);
>> +
>> + num = MIN(size, sizeof(long) - fifo8_num_used(&s->incoming_fifo));
>> + fifo8_push_all(&s->incoming_fifo, buf, num);
>> +
>> + if (fifo8_num_used(&s->incoming_fifo) < len) {
>> + assert(num == 0);
>> + return false;
>> + }
>> +
>> + size -= num;
>> + buf += num;
>> + p = fifo8_pop_buf(&s->incoming_fifo, len, &num);
>> + assert(num == len);
>> +
>> + memcpy(data, p, len);
>> +
>> + if (size > 0) {
>> + fifo8_push_all(&s->incoming_fifo, buf, size);
>> + }
>> +
>> + return true;
>> +}
>> +
>> static void ivshmem_read(void *opaque, const uint8_t *buf, int size)
>> {
>> IVShmemState *s = opaque;
>> @@ -448,26 +484,9 @@ static void ivshmem_read(void *opaque, const uint8_t
>> *buf, int size)
>> int guest_max_eventfd;
>> long incoming_posn;
>>
>> - if (fifo8_is_empty(&s->incoming_fifo) && size == sizeof(incoming_posn))
>> {
>> - memcpy(&incoming_posn, buf, size);
>> - } else {
>> - const uint8_t *p;
>> - uint32_t num;
>> -
>> - IVSHMEM_DPRINTF("short read of %d bytes\n", size);
>> - num = MIN(size, sizeof(long) - fifo8_num_used(&s->incoming_fifo));
>> - fifo8_push_all(&s->incoming_fifo, buf, num);
>> - if (fifo8_num_used(&s->incoming_fifo) < sizeof(incoming_posn)) {
>> - return;
>> - }
>> - size -= num;
>> - buf += num;
>> - p = fifo8_pop_buf(&s->incoming_fifo, sizeof(incoming_posn), &num);
>> - g_assert(num == sizeof(incoming_posn));
>> - memcpy(&incoming_posn, p, sizeof(incoming_posn));
>> - if (size > 0) {
>> - fifo8_push_all(&s->incoming_fifo, buf, size);
>> - }
>> + if (!fifo_update_and_get(s, buf, size,
>> + &incoming_posn, sizeof(incoming_posn))) {
>> + return;
>> }
>>
>> if (incoming_posn < -1) {
>>
>
>
> Fine in principle, I have that reservation about using sizeof(long) as part
> of the interface.
This will be treated in a seperate patch.
--
Marc-André Lureau
