walkero
/
nghttp2
1
0
Fork 0
Code Issues Pull Requests Projects Releases 1 Wiki Activity

Add more comment about local window size adjustment

This commit is contained in:
Tatsuhiro Tsujikawa 2014-10-26 18:34:39 +09:00
parent b3463b20a3
commit 2c335dbc7a
1 changed files with 31 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
lib/nghttp2_helper.c
View File

@ -163,6 +163,32 @@ void nghttp2_downcase(uint8_t *s, size_t len)
}
}
/*
* local_window_size
* ^ *
* | * recv_window_size
* | * * ^
* | * * |
* 0+++++++++
* | * * \
* | * * | This rage is hidden in flow control. But it must be
* v * * / kept in order to restore it when window size is enlarged.
* recv_reduction
* (+ for negative direction)
*
* recv_window_size could be negative if we decrease
* local_window_size more than recv_window_size:
*
* local_window_size
* ^ *
* | *
* | *
* 0++++++++
* | * ^ recv_window_size (negative)
* | * |
* v * *
* recv_reduction
*/
int nghttp2_adjust_local_window_size(int32_t *local_window_size_ptr,
int32_t *recv_window_size_ptr,
int32_t *recv_reduction_ptr,
@ -188,10 +214,11 @@ int nghttp2_adjust_local_window_size(int32_t *local_window_size_ptr,
if(*recv_window_size_ptr < 0) {
*recv_window_size_ptr += recv_reduction_diff;
} else {
/* If *recv_window_size_ptr > 0, then those bytes are
considered to be backed to the remote peer (by
WINDOW_UPDATE with the adjusted *delta_ptr), so it is
effectively 0 now. */
/* If *recv_window_size_ptr > 0, then those bytes are going to
be backed to the remote peer (by WINDOW_UPDATE with the
adjusted *delta_ptr), so it is effectively 0 now. We set
to *recv_reduction_diff, because caller does not take into
account it in *delta_ptr. */
*recv_window_size_ptr = recv_reduction_diff;
}
/* recv_reduction_diff must be paied from *delta_ptr, since it