nghttp2/lib/nghttp2_stream.c

985 lines
24 KiB
C

/*
* nghttp2 - HTTP/2 C Library
*
* Copyright (c) 2012 Tatsuhiro Tsujikawa
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include "nghttp2_stream.h"
#include <assert.h>
#include <stdio.h>
#include "nghttp2_helper.h"
void nghttp2_stream_init(nghttp2_stream *stream, int32_t stream_id,
uint8_t flags,
nghttp2_stream_state initial_state,
int32_t weight,
nghttp2_stream_roots *roots,
int32_t remote_initial_window_size,
int32_t local_initial_window_size,
void *stream_user_data)
{
nghttp2_map_entry_init(&stream->map_entry, stream_id);
stream->stream_id = stream_id;
stream->flags = flags;
stream->state = initial_state;
stream->shut_flags = NGHTTP2_SHUT_NONE;
stream->stream_user_data = stream_user_data;
stream->data_item = NULL;
stream->remote_window_size = remote_initial_window_size;
stream->local_window_size = local_initial_window_size;
stream->recv_window_size = 0;
stream->recv_reduction = 0;
stream->blocked_sent = 0;
stream->dep_prev = NULL;
stream->dep_next = NULL;
stream->sib_prev = NULL;
stream->sib_next = NULL;
stream->closed_next = NULL;
stream->dpri = NGHTTP2_STREAM_DPRI_NO_DATA;
stream->num_substreams = 1;
stream->weight = weight;
stream->effective_weight = stream->weight;
stream->sum_dep_weight = 0;
stream->sum_norest_weight = 0;
stream->roots = roots;
stream->root_prev = NULL;
stream->root_next = NULL;
}
void nghttp2_stream_free(nghttp2_stream *stream)
{
if(stream->flags & NGHTTP2_STREAM_FLAG_DEFERRED_ALL) {
nghttp2_outbound_item_free(stream->data_item);
free(stream->data_item);
}
/* We don't free stream->data_item otherwise. */
}
void nghttp2_stream_shutdown(nghttp2_stream *stream, nghttp2_shut_flag flag)
{
stream->shut_flags |= flag;
}
static int stream_push_data(nghttp2_stream *stream, nghttp2_pq *pq)
{
int rv;
assert(stream->data_item);
assert(stream->data_item->queued == 0);
if(stream->data_item->weight > stream->effective_weight) {
stream->data_item->weight = stream->effective_weight;
}
rv = nghttp2_pq_push(pq, stream->data_item);
if(rv != 0) {
return rv;
}
stream->data_item->queued = 1;
return 0;
}
static nghttp2_stream* stream_first_sib(nghttp2_stream *stream)
{
for(; stream->sib_prev; stream = stream->sib_prev);
return stream;
}
static nghttp2_stream* stream_last_sib(nghttp2_stream *stream)
{
for(; stream->sib_next; stream = stream->sib_next);
return stream;
}
static nghttp2_stream* stream_update_dep_length(nghttp2_stream *stream,
ssize_t delta)
{
stream->num_substreams += delta;
stream = stream_first_sib(stream);
if(stream->dep_prev) {
return stream_update_dep_length(stream->dep_prev, delta);
}
return stream;
}
int32_t nghttp2_stream_dep_distributed_weight(nghttp2_stream *stream,
int32_t weight)
{
weight = stream->weight * weight / stream->sum_dep_weight;
return nghttp2_max(1, weight);
}
int32_t nghttp2_stream_dep_distributed_effective_weight
(nghttp2_stream *stream, int32_t weight)
{
weight = stream->effective_weight * weight / stream->sum_norest_weight;
return nghttp2_max(1, weight);
}
/* Updates effective_weight of descendant streams in subtree of
|stream|. We assume that stream->effective_weight is already set
right. */
static void stream_update_dep_effective_weight(nghttp2_stream *stream)
{
nghttp2_stream *si;
DEBUGF(fprintf(stderr, "stream: update_dep_effective_weight "
"stream(%p)=%d, weight=%d, sum_norest_weight=%d\n",
stream, stream->stream_id, stream->weight,
stream->sum_norest_weight));
/* stream->sum_norest_weight == 0 means there is no
NGHTTP2_STREAM_DPRI_TOP under stream */
if(stream->dpri != NGHTTP2_STREAM_DPRI_NO_DATA ||
stream->sum_norest_weight == 0) {
return;
}
for(si = stream->dep_next; si; si = si->sib_next) {
if(si->dpri != NGHTTP2_STREAM_DPRI_REST) {
si->effective_weight = nghttp2_stream_dep_distributed_effective_weight
(stream, si->weight);
}
stream_update_dep_effective_weight(si);
}
}
static void stream_update_dep_set_rest(nghttp2_stream *stream)
{
if(stream == NULL) {
return;
}
if(stream->dpri == NGHTTP2_STREAM_DPRI_REST) {
return;
}
if(stream->dpri == NGHTTP2_STREAM_DPRI_TOP) {
stream->dpri = NGHTTP2_STREAM_DPRI_REST;
stream_update_dep_set_rest(stream->sib_next);
return;
}
stream_update_dep_set_rest(stream->sib_next);
stream_update_dep_set_rest(stream->dep_next);
}
/*
* Performs dfs starting |stream|, search stream which can become
* NGHTTP2_STREAM_DPRI_TOP and queues its data_item.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory.
*/
static int stream_update_dep_set_top(nghttp2_stream *stream, nghttp2_pq *pq)
{
int rv;
nghttp2_stream *si;
if(stream->dpri == NGHTTP2_STREAM_DPRI_TOP) {
return 0;
}
if(stream->dpri == NGHTTP2_STREAM_DPRI_REST) {
DEBUGF(fprintf(stderr, "stream: stream=%d data is top\n",
stream->stream_id));
if(!stream->data_item->queued) {
rv = stream_push_data(stream, pq);
if(rv != 0) {
return rv;
}
}
stream->dpri = NGHTTP2_STREAM_DPRI_TOP;
return 0;
}
for(si = stream->dep_next; si; si = si->sib_next) {
rv = stream_update_dep_set_top(si, pq);
if(rv != 0) {
return rv;
}
}
return 0;
}
/*
* Updates stream->sum_norest_weight recursively. We have to gather
* effective sum of weight of descendants. If stream->dpri ==
* NGHTTP2_STREAM_DPRI_NO_DATA, we have to go deeper and check that
* any of its descendants has dpri value of NGHTTP2_STREAM_DPRI_TOP.
* If so, we have to add weight of its direct descendants to
* stream->sum_norest_weight. To make this work, this function
* returns 1 if any of its descendants has dpri value of
* NGHTTP2_STREAM_DPRI_TOP, otherwise 0.
*/
static int stream_update_dep_sum_norest_weight(nghttp2_stream *stream)
{
nghttp2_stream *si;
int rv;
stream->sum_norest_weight = 0;
if(stream->dpri == NGHTTP2_STREAM_DPRI_TOP) {
return 1;
}
if(stream->dpri == NGHTTP2_STREAM_DPRI_REST) {
return 0;
}
rv = 0;
for(si = stream->dep_next; si; si = si->sib_next) {
if(stream_update_dep_sum_norest_weight(si)) {
rv = 1;
stream->sum_norest_weight += si->weight;
}
}
return rv;
}
static int stream_update_dep_on_attach_data(nghttp2_stream *stream,
nghttp2_pq *pq)
{
int rv;
nghttp2_stream *root_stream;
stream->dpri = NGHTTP2_STREAM_DPRI_REST;
stream_update_dep_set_rest(stream->dep_next);
root_stream = nghttp2_stream_get_dep_root(stream);
DEBUGF(fprintf(stderr, "root=%p, stream=%p\n", root_stream, stream));
rv = stream_update_dep_set_top(root_stream, pq);
if(rv != 0) {
return rv;
}
stream_update_dep_sum_norest_weight(root_stream);
stream_update_dep_effective_weight(root_stream);
return 0;
}
static int stream_update_dep_on_detach_data(nghttp2_stream *stream,
nghttp2_pq *pq)
{
int rv;
nghttp2_stream *root_stream;
stream->dpri = NGHTTP2_STREAM_DPRI_NO_DATA;
root_stream = nghttp2_stream_get_dep_root(stream);
rv = stream_update_dep_set_top(root_stream, pq);
if(rv != 0) {
return rv;
}
stream_update_dep_sum_norest_weight(root_stream);
stream_update_dep_effective_weight(root_stream);
return 0;
}
int nghttp2_stream_attach_data(nghttp2_stream *stream,
nghttp2_outbound_item *data_item,
nghttp2_pq *pq)
{
assert((stream->flags & NGHTTP2_STREAM_FLAG_DEFERRED_ALL) == 0);
assert(stream->data_item == NULL);
DEBUGF(fprintf(stderr, "stream: stream=%d attach data=%p\n",
stream->stream_id, data_item));
stream->data_item = data_item;
return stream_update_dep_on_attach_data(stream, pq);
}
int nghttp2_stream_detach_data(nghttp2_stream *stream, nghttp2_pq *pq)
{
DEBUGF(fprintf(stderr, "stream: stream=%d detach data=%p\n",
stream->stream_id, stream->data_item));
stream->data_item = NULL;
stream->flags &= ~NGHTTP2_STREAM_FLAG_DEFERRED_ALL;
return stream_update_dep_on_detach_data(stream, pq);
}
int nghttp2_stream_defer_data(nghttp2_stream *stream, uint8_t flags,
nghttp2_pq *pq)
{
assert(stream->data_item);
DEBUGF(fprintf(stderr, "stream: stream=%d defer data=%p cause=%02x\n",
stream->stream_id, stream->data_item, flags));
stream->flags |= flags;
return stream_update_dep_on_detach_data(stream, pq);
}
int nghttp2_stream_resume_deferred_data(nghttp2_stream *stream,
nghttp2_pq *pq)
{
assert(stream->data_item);
DEBUGF(fprintf(stderr, "stream: stream=%d resume data=%p\n",
stream->stream_id, stream->data_item));
stream->flags &= ~NGHTTP2_STREAM_FLAG_DEFERRED_ALL;
return stream_update_dep_on_attach_data(stream, pq);
}
int nghttp2_stream_check_deferred_data(nghttp2_stream *stream)
{
return stream->data_item &&
(stream->flags & NGHTTP2_STREAM_FLAG_DEFERRED_ALL);
}
int nghttp2_stream_check_deferred_by_flow_control(nghttp2_stream *stream)
{
return stream->data_item &&
(stream->flags & NGHTTP2_STREAM_FLAG_DEFERRED_FLOW_CONTROL);
}
static int update_initial_window_size
(int32_t *window_size_ptr,
int32_t new_initial_window_size,
int32_t old_initial_window_size)
{
int64_t new_window_size = (int64_t)(*window_size_ptr) +
new_initial_window_size - old_initial_window_size;
if(INT32_MIN > new_window_size ||
new_window_size > NGHTTP2_MAX_WINDOW_SIZE) {
return -1;
}
*window_size_ptr = new_window_size;
return 0;
}
int nghttp2_stream_update_remote_initial_window_size
(nghttp2_stream *stream,
int32_t new_initial_window_size,
int32_t old_initial_window_size)
{
return update_initial_window_size(&stream->remote_window_size,
new_initial_window_size,
old_initial_window_size);
}
int nghttp2_stream_update_local_initial_window_size
(nghttp2_stream *stream,
int32_t new_initial_window_size,
int32_t old_initial_window_size)
{
return update_initial_window_size(&stream->local_window_size,
new_initial_window_size,
old_initial_window_size);
}
void nghttp2_stream_promise_fulfilled(nghttp2_stream *stream)
{
stream->state = NGHTTP2_STREAM_OPENED;
}
nghttp2_stream* nghttp2_stream_get_dep_root(nghttp2_stream *stream)
{
for(;;) {
if(stream->sib_prev) {
stream = stream->sib_prev;
continue;
}
if(stream->dep_prev) {
stream = stream->dep_prev;
continue;
}
break;
}
return stream;
}
int nghttp2_stream_dep_subtree_find(nghttp2_stream *stream,
nghttp2_stream *target)
{
if(stream == NULL) {
return 0;
}
if(stream == target) {
return 1;
}
if(nghttp2_stream_dep_subtree_find(stream->sib_next, target)) {
return 1;
}
return nghttp2_stream_dep_subtree_find(stream->dep_next, target);
}
void nghttp2_stream_dep_insert(nghttp2_stream *dep_stream,
nghttp2_stream *stream)
{
nghttp2_stream *si;
nghttp2_stream *root_stream;
assert(stream->data_item == NULL);
DEBUGF(fprintf(stderr,
"stream: dep_insert dep_stream(%p)=%d, stream(%p)=%d\n",
dep_stream, dep_stream->stream_id,
stream, stream->stream_id));
stream->sum_dep_weight = dep_stream->sum_dep_weight;
dep_stream->sum_dep_weight = stream->weight;
if(dep_stream->dep_next) {
for(si = dep_stream->dep_next; si; si = si->sib_next) {
stream->num_substreams += si->num_substreams;
}
stream->dep_next = dep_stream->dep_next;
stream->dep_next->dep_prev = stream;
}
dep_stream->dep_next = stream;
stream->dep_prev = dep_stream;
root_stream = stream_update_dep_length(dep_stream, 1);
stream_update_dep_sum_norest_weight(root_stream);
stream_update_dep_effective_weight(root_stream);
++stream->roots->num_streams;
}
void nghttp2_stream_dep_add(nghttp2_stream *dep_stream,
nghttp2_stream *stream)
{
nghttp2_stream *last_sib;
nghttp2_stream *root_stream;
assert(stream->data_item == NULL);
DEBUGF(fprintf(stderr,
"stream: dep_add dep_stream(%p)=%d, stream(%p)=%d\n",
dep_stream, dep_stream->stream_id,
stream, stream->stream_id));
root_stream = stream_update_dep_length(dep_stream, 1);
dep_stream->sum_dep_weight += stream->weight;
if(dep_stream->dep_next == NULL) {
dep_stream->dep_next = stream;
stream->dep_prev = dep_stream;
} else {
last_sib = stream_last_sib(dep_stream->dep_next);
last_sib->sib_next = stream;
stream->sib_prev = last_sib;
}
stream_update_dep_sum_norest_weight(root_stream);
stream_update_dep_effective_weight(root_stream);
++stream->roots->num_streams;
}
void nghttp2_stream_dep_remove(nghttp2_stream *stream)
{
nghttp2_stream *prev, *next, *dep_next, *dep_prev, *si, *root_stream;
int32_t sum_dep_weight_delta;
root_stream = NULL;
DEBUGF(fprintf(stderr, "stream: dep_remove stream(%p)=%d\n",
stream, stream->stream_id));
/* Distribute weight of |stream| to direct descendants */
sum_dep_weight_delta = -stream->weight;
for(si = stream->dep_next; si; si = si->sib_next) {
si->weight = nghttp2_stream_dep_distributed_weight(stream, si->weight);
sum_dep_weight_delta += si->weight;
}
prev = stream_first_sib(stream);
dep_prev = prev->dep_prev;
if(dep_prev) {
root_stream = stream_update_dep_length(dep_prev, -1);
dep_prev->sum_dep_weight += sum_dep_weight_delta;
}
if(stream->sib_prev) {
prev = stream->sib_prev;
dep_next = stream->dep_next;
if(dep_next) {
dep_next->dep_prev = NULL;
prev->sib_next = dep_next;
dep_next->sib_prev = prev;
} else {
next = stream->sib_next;
prev->sib_next = next;
if(next) {
next->sib_prev = prev;
}
}
} else if(stream->dep_prev) {
prev = stream->dep_prev;
dep_next = stream->dep_next;
if(dep_next) {
prev->dep_next = dep_next;
dep_next->dep_prev = prev;
} else if(stream->sib_next) {
next = stream->sib_next;
prev->dep_next = next;
next->dep_prev = prev;
next->sib_prev = NULL;
} else {
prev->dep_next = NULL;
dep_next = NULL;
}
} else {
nghttp2_stream_roots_remove(stream->roots, stream);
dep_next = NULL;
/* stream is a root of tree. Removing stream makes its
descendants a root of its own subtree. */
for(si = stream->dep_next; si;) {
next = si->sib_next;
si->dep_prev = NULL;
si->sib_prev = NULL;
si->sib_next = NULL;
/* We already distributed weight of |stream| to this. */
si->effective_weight = si->weight;
nghttp2_stream_roots_add(si->roots, si);
si = next;
}
}
if(dep_next && stream->sib_next) {
prev = stream_last_sib(dep_next);
next = stream->sib_next;
prev->sib_next = next;
next->sib_prev = prev;
}
if(root_stream) {
stream_update_dep_sum_norest_weight(root_stream);
stream_update_dep_effective_weight(root_stream);
}
stream->num_substreams = 1;
stream->sum_dep_weight = 0;
stream->dep_prev = NULL;
stream->dep_next = NULL;
stream->sib_prev = NULL;
stream->sib_next = NULL;
--stream->roots->num_streams;
}
int nghttp2_stream_dep_insert_subtree(nghttp2_stream *dep_stream,
nghttp2_stream *stream,
nghttp2_pq *pq)
{
nghttp2_stream *last_sib;
nghttp2_stream *dep_next;
nghttp2_stream *root_stream;
size_t delta_substreams;
int rv;
DEBUGF(fprintf(stderr, "stream: dep_insert_subtree dep_stream(%p)=%d "
"stream(%p)=%d\n",
dep_stream, dep_stream->stream_id,
stream, stream->stream_id));
delta_substreams = stream->num_substreams;
stream_update_dep_set_rest(stream);
if(dep_stream->dep_next) {
/* dep_stream->num_substreams includes dep_stream itself */
stream->num_substreams += dep_stream->num_substreams - 1;
stream->sum_dep_weight += dep_stream->sum_dep_weight;
dep_stream->sum_dep_weight = stream->weight;
dep_next = dep_stream->dep_next;
stream_update_dep_set_rest(dep_next);
dep_stream->dep_next = stream;
stream->dep_prev = dep_stream;
if(stream->dep_next) {
last_sib = stream_last_sib(stream->dep_next);
last_sib->sib_next = dep_next;
dep_next->sib_prev = last_sib;
dep_next->dep_prev = NULL;
} else {
stream->dep_next = dep_next;
dep_next->dep_prev = stream;
}
} else {
dep_stream->dep_next = stream;
stream->dep_prev = dep_stream;
assert(dep_stream->sum_dep_weight == 0);
dep_stream->sum_dep_weight = stream->weight;
}
root_stream = stream_update_dep_length(dep_stream, delta_substreams);
rv = stream_update_dep_set_top(root_stream, pq);
if(rv != 0) {
return rv;
}
stream_update_dep_sum_norest_weight(root_stream);
stream_update_dep_effective_weight(root_stream);
return 0;
}
int nghttp2_stream_dep_add_subtree(nghttp2_stream *dep_stream,
nghttp2_stream *stream,
nghttp2_pq *pq)
{
nghttp2_stream *last_sib;
nghttp2_stream *root_stream;
int rv;
DEBUGF(fprintf(stderr, "stream: dep_add_subtree dep_stream(%p)=%d "
"stream(%p)=%d\n",
dep_stream, dep_stream->stream_id,
stream, stream->stream_id));
stream_update_dep_set_rest(stream);
if(dep_stream->dep_next) {
dep_stream->sum_dep_weight += stream->weight;
last_sib = stream_last_sib(dep_stream->dep_next);
last_sib->sib_next = stream;
stream->sib_prev = last_sib;
} else {
dep_stream->dep_next = stream;
stream->dep_prev = dep_stream;
assert(dep_stream->sum_dep_weight == 0);
dep_stream->sum_dep_weight = stream->weight;
}
root_stream = stream_update_dep_length(dep_stream, stream->num_substreams);
rv = stream_update_dep_set_top(root_stream, pq);
if(rv != 0) {
return rv;
}
stream_update_dep_sum_norest_weight(root_stream);
stream_update_dep_effective_weight(root_stream);
return 0;
}
void nghttp2_stream_dep_remove_subtree(nghttp2_stream *stream)
{
nghttp2_stream *prev, *next, *dep_prev, *root_stream;
DEBUGF(fprintf(stderr, "stream: dep_remove_subtree stream(%p)=%d\n",
stream, stream->stream_id));
if(stream->sib_prev) {
prev = stream->sib_prev;
prev->sib_next = stream->sib_next;
if(prev->sib_next) {
prev->sib_next->sib_prev = prev;
}
prev = stream_first_sib(prev);
dep_prev = prev->dep_prev;
} else if(stream->dep_prev) {
dep_prev = stream->dep_prev;
next = stream->sib_next;
dep_prev->dep_next = next;
if(next) {
next->dep_prev = dep_prev;
next->sib_prev = NULL;
}
} else {
nghttp2_stream_roots_remove(stream->roots, stream);
dep_prev = NULL;
}
if(dep_prev) {
dep_prev->sum_dep_weight -= stream->weight;
root_stream = stream_update_dep_length(dep_prev, -stream->num_substreams);
stream_update_dep_sum_norest_weight(root_stream);
stream_update_dep_effective_weight(root_stream);
}
stream->sib_prev = NULL;
stream->sib_next = NULL;
stream->dep_prev = NULL;
}
int nghttp2_stream_dep_make_root(nghttp2_stream *stream, nghttp2_pq *pq)
{
int rv;
DEBUGF(fprintf(stderr, "stream: dep_make_root stream(%p)=%d\n",
stream, stream->stream_id));
nghttp2_stream_roots_add(stream->roots, stream);
stream_update_dep_set_rest(stream);
stream->effective_weight = stream->weight;
rv = stream_update_dep_set_top(stream, pq);
if(rv != 0) {
return rv;
}
stream_update_dep_sum_norest_weight(stream);
stream_update_dep_effective_weight(stream);
return 0;
}
int nghttp2_stream_dep_all_your_stream_are_belong_to_us
(nghttp2_stream *stream, nghttp2_pq *pq)
{
nghttp2_stream *first, *si;
DEBUGF(fprintf(stderr, "stream: ALL YOUR STREAM ARE BELONG TO US "
"stream(%p)=%d\n",
stream, stream->stream_id));
first = stream->roots->head;
/* stream must not be include in stream->roots->head list */
assert(first != stream);
if(first) {
nghttp2_stream *prev;
prev = first;
DEBUGF(fprintf(stderr, "stream: root stream(%p)=%d\n",
first, first->stream_id));
stream->sum_dep_weight += first->weight;
stream->num_substreams += first->num_substreams;
for(si = first->root_next; si; si = si->root_next) {
assert(si != stream);
DEBUGF(fprintf(stderr, "stream: root stream(%p)=%d\n",
si, si->stream_id));
fprintf(stderr, "w=%d, sum=%d\n",
si->weight, stream->sum_dep_weight);
stream->sum_dep_weight += si->weight;
stream->num_substreams += si->num_substreams;
si->sib_prev = prev;
prev->sib_next = si;
prev = si;
}
if(stream->dep_next) {
nghttp2_stream *last_sib;
last_sib = stream_last_sib(stream->dep_next);
last_sib->sib_next = first;
first->sib_prev = last_sib;
} else {
stream->dep_next = first;
first->dep_prev = stream;
}
}
nghttp2_stream_roots_remove_all(stream->roots);
return nghttp2_stream_dep_make_root(stream, pq);
}
int nghttp2_stream_in_dep_tree(nghttp2_stream *stream)
{
return stream->dep_prev || stream->dep_next ||
stream->sib_prev || stream->sib_next ||
stream->root_next || stream->root_prev ||
stream->roots->head == stream;
}
void nghttp2_stream_roots_init(nghttp2_stream_roots *roots)
{
roots->head = NULL;
roots->num_streams = 0;
}
void nghttp2_stream_roots_free(nghttp2_stream_roots *roots)
{}
void nghttp2_stream_roots_add(nghttp2_stream_roots *roots,
nghttp2_stream *stream)
{
if(roots->head) {
nghttp2_stream *si;
for(si = roots->head; si; si = si->root_next) {
if(si == stream) {
assert(0);
}
}
stream->root_next = roots->head;
roots->head->root_prev = stream;
}
roots->head = stream;
}
void nghttp2_stream_roots_remove(nghttp2_stream_roots *roots,
nghttp2_stream *stream)
{
nghttp2_stream *root_prev, *root_next;
root_prev = stream->root_prev;
root_next = stream->root_next;
if(root_prev) {
root_prev->root_next = root_next;
if(root_next) {
root_next->root_prev = root_prev;
}
} else {
if(root_next) {
root_next->root_prev = NULL;
}
roots->head = root_next;
}
stream->root_prev = NULL;
stream->root_next = NULL;
}
void nghttp2_stream_roots_remove_all(nghttp2_stream_roots *roots)
{
nghttp2_stream *si, *next;
for(si = roots->head; si;) {
next = si->root_next;
si->root_prev = NULL;
si->root_next = NULL;
si = next;
}
roots->head = NULL;
}