Thanks for the comments on my threading/programming practice, but it
really didn't address my real problem though. Any ideas on that part?

Some answers to the questions:
1) The naming scheme came from a curl example I found,
write_memory_callback writes memory which is for a CURL get (or read
from my point of view) and is used with the CURLOPT_WRITEFUNCTION
option.
2) I could do the stuct, but thats sort of irrelevant to my problem.
3) BIG_BUFFER_SIZE is 128KB and I can recreate this moving 1,000 byte
items, so this shouldn't have any impact. But out of curiosity the docs
that i've run into haven't indicated that I cant move less than curl is
ready to provide (unless I return none prematurely). I have moved sizes
much larger than 128KB without problems (when doing only PUTs or GETs)
so it "seems" ok.
4) I do clobber the data every time I'm called. Thats intentional and
should not be related to my problem.

Rob

On Aug 24, 2004, at 5:02 PM, Daniel Stenberg wrote:

> On Tue, 24 Aug 2004, Rob Mason wrote:
>
>> Read callback:
>> static size_t write_memory_callback(void *ptr, size_t size, size_t
>> nmemb, void *stream)
>
> I assume you mixed your labels so that this is the write callback! ;-)
>
>> thread_id = get_our_thread_id();
>
> I find your programming practise weird here. Why not pass in a pointer
> to a struct in the stream argument and you won't have to fetch the
> tread_id here.
>
>> if ((nmemb*size) > BIG_BUFFER_SIZE)
>> {
>> my_size = BIG_BUFFER_SIZE;
>> }
>
> This looks very weird. How big is BIG_BUFFER_SIZE? Why don't you allow
> larger buffer chunks? libcurl may send CURL_MAX_WRITE_SIZE bytes at
> once.
>
> But if this condition is met, you'd return a different size than what
> was passed in, and then libcurl would've stopped the transfer and
> returned an error and since this doesn't happen I take it your
> BIG_BUFFER_SIZE is at least big enough to very seldomly happen in
> practise in your app.
>
>> if (my_size > 0)
>> {
>> memcpy(stream, ptr, my_size);
>> }
>
> You copy the downloaded data to the same target buffer every time this
> callback is called?
>
>> sizeLeft[thread_id] += my_size;
>
> ... and this is another global variable I would rather use a struct to
> avoid, as described above.
>
> --
> Daniel Stenberg -- http://curl.haxx.se -- http://daniel.haxx.se
> Dedicated custom curl help for hire: http://haxx.se/curl.html
>
Received on 2004-08-24