diff options
Diffstat (limited to 'lib/README.multi_socket')
| -rw-r--r-- | lib/README.multi_socket | 30 |
1 files changed, 9 insertions, 21 deletions
diff --git a/lib/README.multi_socket b/lib/README.multi_socket index 606638670..d91e1d9f2 100644 --- a/lib/README.multi_socket +++ b/lib/README.multi_socket @@ -16,28 +16,16 @@ Implementation of the curl_multi_socket API information about what socket to wait for what action on, and the callback only gets called if the status of that socket has changed. - In the API draft from before, we have a timeout argument on a per socket - basis and we also allowed curl_multi_socket_action() to pass in an 'easy - handle' instead of socket to allow libcurl to shortcut a lookup and work on - the affected easy handle right away. Both these turned out to be bad ideas. - - The timeout argument was removed from the socket callback since after much - thinking I came to the conclusion that we really don't want to handle - timeouts on a per socket basis. We need it on a per transfer (easy handle) - basis and thus we can't provide it in the callbacks in a nice way. Instead, - we have to offer a curl_multi_timeout() that returns the largest amount of - time we should wait before we call the "timeout action" of libcurl, to - trigger the proper internal timeout action on the affected transfer. To get - this to work, I added a struct to each easy handle in which we store an - "expire time" (if any). The structs are then "splay sorted" so that we can - add and remove times from the linked list and yet somewhat swiftly figure - out 1 - how long time there is until the next timer expires and 2 - which - timer (handle) should we take care of now. Of course, the upside of all this - is that we get a curl_multi_timeout() that should also work with old-style - applications that use curl_multi_perform(). - We also added a timer callback that makes libcurl call the application when - the timeout value changes, and you set that with curl_multi_setopt(). + the timeout value changes, and you set that with curl_multi_setopt() and the + CURLMOPT_TIMERFUNCTION option. To get this to work, Internally, there's an + added a struct to each easy handle in which we store an "expire time" (if + any). The structs are then "splay sorted" so that we can add and remove + times from the linked list and yet somewhat swiftly figure out both how long + time there is until the next nearest timer expires and which timer (handle) + we should take care of now. Of course, the upside of all this is that we get + a curl_multi_timeout() that should also work with old-style applications + that use curl_multi_perform(). We created an internal "socket to easy handles" hash table that given a socket (file descriptor) return the easy handle that waits for action on |