diff options
Diffstat (limited to 'lib/nghttp2_stream.c')
| -rw-r--r-- | lib/nghttp2_stream.c | 1016 |
1 files changed, 1016 insertions, 0 deletions
diff --git a/lib/nghttp2_stream.c b/lib/nghttp2_stream.c new file mode 100644 index 0000000..f1951f8 --- /dev/null +++ b/lib/nghttp2_stream.c @@ -0,0 +1,1016 @@ +/* + * 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_session.h" +#include "nghttp2_helper.h" +#include "nghttp2_debug.h" +#include "nghttp2_frame.h" + +/* Maximum distance between any two stream's cycle in the same + priority queue. Imagine stream A's cycle is A, and stream B's + cycle is B, and A < B. The cycle is unsigned 32 bit integer, it + may get overflow. Because of how we calculate the next cycle + value, if B - A is less than or equals to + NGHTTP2_MAX_CYCLE_DISTANCE, A and B are in the same scale, in other + words, B is really greater than or equal to A. Otherwise, A is a + result of overflow, and it is actually A > B if we consider that + fact. */ +#define NGHTTP2_MAX_CYCLE_DISTANCE \ + ((uint64_t)NGHTTP2_MAX_FRAME_SIZE_MAX * 256 + 255) + +static int stream_less(const void *lhsx, const void *rhsx) { + const nghttp2_stream *lhs, *rhs; + + lhs = nghttp2_struct_of(lhsx, nghttp2_stream, pq_entry); + rhs = nghttp2_struct_of(rhsx, nghttp2_stream, pq_entry); + + if (lhs->cycle == rhs->cycle) { + return lhs->seq < rhs->seq; + } + + return rhs->cycle - lhs->cycle <= NGHTTP2_MAX_CYCLE_DISTANCE; +} + +void nghttp2_stream_init(nghttp2_stream *stream, int32_t stream_id, + uint8_t flags, nghttp2_stream_state initial_state, + int32_t weight, int32_t remote_initial_window_size, + int32_t local_initial_window_size, + void *stream_user_data, nghttp2_mem *mem) { + nghttp2_pq_init(&stream->obq, stream_less, mem); + + 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->item = NULL; + stream->remote_window_size = remote_initial_window_size; + stream->local_window_size = local_initial_window_size; + stream->recv_window_size = 0; + stream->consumed_size = 0; + stream->recv_reduction = 0; + stream->window_update_queued = 0; + + stream->dep_prev = NULL; + stream->dep_next = NULL; + stream->sib_prev = NULL; + stream->sib_next = NULL; + + stream->closed_prev = NULL; + stream->closed_next = NULL; + + stream->weight = weight; + stream->sum_dep_weight = 0; + + stream->http_flags = NGHTTP2_HTTP_FLAG_NONE; + stream->content_length = -1; + stream->recv_content_length = 0; + stream->status_code = -1; + + stream->queued = 0; + stream->descendant_last_cycle = 0; + stream->cycle = 0; + stream->pending_penalty = 0; + stream->descendant_next_seq = 0; + stream->seq = 0; + stream->last_writelen = 0; + + stream->extpri = stream->http_extpri = NGHTTP2_EXTPRI_DEFAULT_URGENCY; +} + +void nghttp2_stream_free(nghttp2_stream *stream) { + nghttp2_pq_free(&stream->obq); + /* We don't free stream->item. If it is assigned to aob, then + active_outbound_item_reset() will delete it. Otherwise, + nghttp2_stream_close() or session_del() will delete it. */ +} + +void nghttp2_stream_shutdown(nghttp2_stream *stream, nghttp2_shut_flag flag) { + stream->shut_flags = (uint8_t)(stream->shut_flags | flag); +} + +/* + * Returns nonzero if |stream| is active. This function does not take + * into account its descendants. + */ +static int stream_active(nghttp2_stream *stream) { + return stream->item && + (stream->flags & NGHTTP2_STREAM_FLAG_DEFERRED_ALL) == 0; +} + +/* + * Returns nonzero if |stream| or one of its descendants is active + */ +static int stream_subtree_active(nghttp2_stream *stream) { + return stream_active(stream) || !nghttp2_pq_empty(&stream->obq); +} + +/* + * Returns next cycle for |stream|. + */ +static void stream_next_cycle(nghttp2_stream *stream, uint64_t last_cycle) { + uint64_t penalty; + + penalty = (uint64_t)stream->last_writelen * NGHTTP2_MAX_WEIGHT + + stream->pending_penalty; + + stream->cycle = last_cycle + penalty / (uint32_t)stream->weight; + stream->pending_penalty = (uint32_t)(penalty % (uint32_t)stream->weight); +} + +static int stream_obq_push(nghttp2_stream *dep_stream, nghttp2_stream *stream) { + int rv; + + for (; dep_stream && !stream->queued; + stream = dep_stream, dep_stream = dep_stream->dep_prev) { + stream_next_cycle(stream, dep_stream->descendant_last_cycle); + stream->seq = dep_stream->descendant_next_seq++; + + DEBUGF("stream: stream=%d obq push cycle=%lu\n", stream->stream_id, + stream->cycle); + + DEBUGF("stream: push stream %d to stream %d\n", stream->stream_id, + dep_stream->stream_id); + + rv = nghttp2_pq_push(&dep_stream->obq, &stream->pq_entry); + if (rv != 0) { + return rv; + } + stream->queued = 1; + } + + return 0; +} + +/* + * Removes |stream| from parent's obq. If removal of |stream| makes + * parent's obq empty, and parent is not active, then parent is also + * removed. This process is repeated recursively. + */ +static void stream_obq_remove(nghttp2_stream *stream) { + nghttp2_stream *dep_stream; + + dep_stream = stream->dep_prev; + + if (!stream->queued) { + return; + } + + for (; dep_stream; stream = dep_stream, dep_stream = dep_stream->dep_prev) { + DEBUGF("stream: remove stream %d from stream %d\n", stream->stream_id, + dep_stream->stream_id); + + nghttp2_pq_remove(&dep_stream->obq, &stream->pq_entry); + + assert(stream->queued); + + stream->queued = 0; + stream->cycle = 0; + stream->pending_penalty = 0; + stream->descendant_last_cycle = 0; + stream->last_writelen = 0; + + if (stream_subtree_active(dep_stream)) { + return; + } + } +} + +/* + * Moves |stream| from |src|'s obq to |dest|'s obq. Removal from + * |src|'s obq is just done calling nghttp2_pq_remove(), so it does + * not recursively remove |src| and ancestors, like + * stream_obq_remove(). + */ +static int stream_obq_move(nghttp2_stream *dest, nghttp2_stream *src, + nghttp2_stream *stream) { + if (!stream->queued) { + return 0; + } + + DEBUGF("stream: remove stream %d from stream %d (move)\n", stream->stream_id, + src->stream_id); + + nghttp2_pq_remove(&src->obq, &stream->pq_entry); + stream->queued = 0; + + return stream_obq_push(dest, stream); +} + +void nghttp2_stream_reschedule(nghttp2_stream *stream) { + nghttp2_stream *dep_stream; + + assert(stream->queued); + + dep_stream = stream->dep_prev; + + for (; dep_stream; stream = dep_stream, dep_stream = dep_stream->dep_prev) { + nghttp2_pq_remove(&dep_stream->obq, &stream->pq_entry); + + stream_next_cycle(stream, dep_stream->descendant_last_cycle); + stream->seq = dep_stream->descendant_next_seq++; + + nghttp2_pq_push(&dep_stream->obq, &stream->pq_entry); + + DEBUGF("stream: stream=%d obq resched cycle=%lu\n", stream->stream_id, + stream->cycle); + + dep_stream->last_writelen = stream->last_writelen; + } +} + +void nghttp2_stream_change_weight(nghttp2_stream *stream, int32_t weight) { + nghttp2_stream *dep_stream; + uint64_t last_cycle; + int32_t old_weight; + uint64_t wlen_penalty; + + if (stream->weight == weight) { + return; + } + + old_weight = stream->weight; + stream->weight = weight; + + dep_stream = stream->dep_prev; + + if (!dep_stream) { + return; + } + + dep_stream->sum_dep_weight += weight - old_weight; + + if (!stream->queued) { + return; + } + + nghttp2_pq_remove(&dep_stream->obq, &stream->pq_entry); + + wlen_penalty = (uint64_t)stream->last_writelen * NGHTTP2_MAX_WEIGHT; + + /* Compute old stream->pending_penalty we used to calculate + stream->cycle */ + stream->pending_penalty = + (uint32_t)((stream->pending_penalty + (uint32_t)old_weight - + (wlen_penalty % (uint32_t)old_weight)) % + (uint32_t)old_weight); + + last_cycle = stream->cycle - + (wlen_penalty + stream->pending_penalty) / (uint32_t)old_weight; + + /* Now we have old stream->pending_penalty and new stream->weight in + place */ + stream_next_cycle(stream, last_cycle); + + if (dep_stream->descendant_last_cycle - stream->cycle <= + NGHTTP2_MAX_CYCLE_DISTANCE) { + stream->cycle = dep_stream->descendant_last_cycle; + } + + /* Continue to use same stream->seq */ + + nghttp2_pq_push(&dep_stream->obq, &stream->pq_entry); + + DEBUGF("stream: stream=%d obq resched cycle=%lu\n", stream->stream_id, + stream->cycle); +} + +static nghttp2_stream *stream_last_sib(nghttp2_stream *stream) { + for (; stream->sib_next; stream = stream->sib_next) + ; + + 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); +} + +#ifdef STREAM_DEP_DEBUG + +static void ensure_inactive(nghttp2_stream *stream) { + nghttp2_stream *si; + + if (stream->queued) { + fprintf(stderr, "stream(%p)=%d, stream->queued = 1; want 0\n", stream, + stream->stream_id); + assert(0); + } + + if (stream_active(stream)) { + fprintf(stderr, "stream(%p)=%d, stream_active(stream) = 1; want 0\n", + stream, stream->stream_id); + assert(0); + } + + if (!nghttp2_pq_empty(&stream->obq)) { + fprintf(stderr, "stream(%p)=%d, nghttp2_pq_size() = %zu; want 0\n", stream, + stream->stream_id, nghttp2_pq_size(&stream->obq)); + assert(0); + } + + for (si = stream->dep_next; si; si = si->sib_next) { + ensure_inactive(si); + } +} + +static void check_queued(nghttp2_stream *stream) { + nghttp2_stream *si; + int queued; + + if (stream->queued) { + if (!stream_subtree_active(stream)) { + fprintf(stderr, + "stream(%p)=%d, stream->queued == 1, but " + "stream_active() == %d and nghttp2_pq_size(&stream->obq) = %zu\n", + stream, stream->stream_id, stream_active(stream), + nghttp2_pq_size(&stream->obq)); + assert(0); + } + if (!stream_active(stream)) { + queued = 0; + for (si = stream->dep_next; si; si = si->sib_next) { + if (si->queued) { + ++queued; + } + } + if (queued == 0) { + fprintf(stderr, + "stream(%p)=%d, stream->queued == 1, and " + "!stream_active(), but no descendants is queued\n", + stream, stream->stream_id); + assert(0); + } + } + + for (si = stream->dep_next; si; si = si->sib_next) { + check_queued(si); + } + } else { + if (stream_active(stream) || !nghttp2_pq_empty(&stream->obq)) { + fprintf(stderr, + "stream(%p) = %d, stream->queued == 0, but " + "stream_active(stream) == %d and " + "nghttp2_pq_size(&stream->obq) = %zu\n", + stream, stream->stream_id, stream_active(stream), + nghttp2_pq_size(&stream->obq)); + assert(0); + } + for (si = stream->dep_next; si; si = si->sib_next) { + ensure_inactive(si); + } + } +} + +static void check_sum_dep(nghttp2_stream *stream) { + nghttp2_stream *si; + int32_t n = 0; + for (si = stream->dep_next; si; si = si->sib_next) { + n += si->weight; + } + if (n != stream->sum_dep_weight) { + fprintf(stderr, "stream(%p)=%d, sum_dep_weight = %d; want %d\n", stream, + stream->stream_id, n, stream->sum_dep_weight); + assert(0); + } + for (si = stream->dep_next; si; si = si->sib_next) { + check_sum_dep(si); + } +} + +static void check_dep_prev(nghttp2_stream *stream) { + nghttp2_stream *si; + for (si = stream->dep_next; si; si = si->sib_next) { + if (si->dep_prev != stream) { + fprintf(stderr, "si->dep_prev = %p; want %p\n", si->dep_prev, stream); + assert(0); + } + check_dep_prev(si); + } +} + +#endif /* STREAM_DEP_DEBUG */ + +#ifdef STREAM_DEP_DEBUG +static void validate_tree(nghttp2_stream *stream) { + nghttp2_stream *si; + + if (!stream) { + return; + } + + for (; stream->dep_prev; stream = stream->dep_prev) + ; + + assert(stream->stream_id == 0); + assert(!stream->queued); + + fprintf(stderr, "checking...\n"); + if (nghttp2_pq_empty(&stream->obq)) { + fprintf(stderr, "root obq empty\n"); + for (si = stream->dep_next; si; si = si->sib_next) { + ensure_inactive(si); + } + } else { + for (si = stream->dep_next; si; si = si->sib_next) { + check_queued(si); + } + } + + check_sum_dep(stream); + check_dep_prev(stream); +} +#else /* !STREAM_DEP_DEBUG */ +static void validate_tree(nghttp2_stream *stream) { (void)stream; } +#endif /* !STREAM_DEP_DEBUG*/ + +static int stream_update_dep_on_attach_item(nghttp2_stream *stream) { + int rv; + + rv = stream_obq_push(stream->dep_prev, stream); + if (rv != 0) { + return rv; + } + + validate_tree(stream); + return 0; +} + +static void stream_update_dep_on_detach_item(nghttp2_stream *stream) { + if (nghttp2_pq_empty(&stream->obq)) { + stream_obq_remove(stream); + } + + validate_tree(stream); +} + +int nghttp2_stream_attach_item(nghttp2_stream *stream, + nghttp2_outbound_item *item) { + int rv; + + assert((stream->flags & NGHTTP2_STREAM_FLAG_DEFERRED_ALL) == 0); + assert(stream->item == NULL); + + DEBUGF("stream: stream=%d attach item=%p\n", stream->stream_id, item); + + stream->item = item; + + if (stream->flags & NGHTTP2_STREAM_FLAG_NO_RFC7540_PRIORITIES) { + return 0; + } + + rv = stream_update_dep_on_attach_item(stream); + if (rv != 0) { + /* This may relave stream->queued == 1, but stream->item == NULL. + But only consequence of this error is fatal one, and session + destruction. In that execution path, these inconsistency does + not matter. */ + stream->item = NULL; + return rv; + } + + return 0; +} + +void nghttp2_stream_detach_item(nghttp2_stream *stream) { + DEBUGF("stream: stream=%d detach item=%p\n", stream->stream_id, stream->item); + + stream->item = NULL; + stream->flags = (uint8_t)(stream->flags & ~NGHTTP2_STREAM_FLAG_DEFERRED_ALL); + + if (stream->flags & NGHTTP2_STREAM_FLAG_NO_RFC7540_PRIORITIES) { + return; + } + + stream_update_dep_on_detach_item(stream); +} + +void nghttp2_stream_defer_item(nghttp2_stream *stream, uint8_t flags) { + assert(stream->item); + + DEBUGF("stream: stream=%d defer item=%p cause=%02x\n", stream->stream_id, + stream->item, flags); + + stream->flags |= flags; + + if (stream->flags & NGHTTP2_STREAM_FLAG_NO_RFC7540_PRIORITIES) { + return; + } + + stream_update_dep_on_detach_item(stream); +} + +int nghttp2_stream_resume_deferred_item(nghttp2_stream *stream, uint8_t flags) { + assert(stream->item); + + DEBUGF("stream: stream=%d resume item=%p flags=%02x\n", stream->stream_id, + stream->item, flags); + + stream->flags = (uint8_t)(stream->flags & ~flags); + + if (stream->flags & NGHTTP2_STREAM_FLAG_DEFERRED_ALL) { + return 0; + } + + if (stream->flags & NGHTTP2_STREAM_FLAG_NO_RFC7540_PRIORITIES) { + return 0; + } + + return stream_update_dep_on_attach_item(stream); +} + +int nghttp2_stream_check_deferred_item(nghttp2_stream *stream) { + return stream->item && (stream->flags & NGHTTP2_STREAM_FLAG_DEFERRED_ALL); +} + +int nghttp2_stream_check_deferred_by_flow_control(nghttp2_stream *stream) { + return stream->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 = (int32_t)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; + stream->flags = (uint8_t)(stream->flags & ~NGHTTP2_STREAM_FLAG_PUSH); +} + +int nghttp2_stream_dep_find_ancestor(nghttp2_stream *stream, + nghttp2_stream *target) { + for (; stream; stream = stream->dep_prev) { + if (stream == target) { + return 1; + } + } + return 0; +} + +int nghttp2_stream_dep_insert(nghttp2_stream *dep_stream, + nghttp2_stream *stream) { + nghttp2_stream *si; + int rv; + + DEBUGF("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) { + si->dep_prev = stream; + if (si->queued) { + rv = stream_obq_move(stream, dep_stream, si); + if (rv != 0) { + return rv; + } + } + } + + if (stream_subtree_active(stream)) { + rv = stream_obq_push(dep_stream, stream); + if (rv != 0) { + return rv; + } + } + + stream->dep_next = dep_stream->dep_next; + } + + dep_stream->dep_next = stream; + stream->dep_prev = dep_stream; + + validate_tree(stream); + + return 0; +} + +static void set_dep_prev(nghttp2_stream *stream, nghttp2_stream *dep) { + for (; stream; stream = stream->sib_next) { + stream->dep_prev = dep; + } +} + +static void link_dep(nghttp2_stream *dep_stream, nghttp2_stream *stream) { + dep_stream->dep_next = stream; + if (stream) { + stream->dep_prev = dep_stream; + } +} + +static void link_sib(nghttp2_stream *a, nghttp2_stream *b) { + a->sib_next = b; + if (b) { + b->sib_prev = a; + } +} + +static void insert_link_dep(nghttp2_stream *dep_stream, + nghttp2_stream *stream) { + nghttp2_stream *sib_next; + + assert(stream->sib_prev == NULL); + + sib_next = dep_stream->dep_next; + + link_sib(stream, sib_next); + + link_dep(dep_stream, stream); +} + +static void unlink_sib(nghttp2_stream *stream) { + nghttp2_stream *prev, *next, *dep_next; + + prev = stream->sib_prev; + dep_next = stream->dep_next; + + assert(prev); + + if (dep_next) { + /* + * prev--stream(--sib_next--...) + * | + * dep_next + */ + + link_sib(prev, dep_next); + + set_dep_prev(dep_next, stream->dep_prev); + + if (stream->sib_next) { + link_sib(stream_last_sib(dep_next), stream->sib_next); + } + } else { + /* + * prev--stream(--sib_next--...) + */ + next = stream->sib_next; + + prev->sib_next = next; + + if (next) { + next->sib_prev = prev; + } + } +} + +static void unlink_dep(nghttp2_stream *stream) { + nghttp2_stream *prev, *next, *dep_next; + + prev = stream->dep_prev; + dep_next = stream->dep_next; + + assert(prev); + + if (dep_next) { + /* + * prev + * | + * stream(--sib_next--...) + * | + * dep_next + */ + link_dep(prev, dep_next); + + set_dep_prev(dep_next, stream->dep_prev); + + if (stream->sib_next) { + link_sib(stream_last_sib(dep_next), stream->sib_next); + } + + } else if (stream->sib_next) { + /* + * prev + * | + * stream--sib_next + */ + next = stream->sib_next; + + next->sib_prev = NULL; + + link_dep(prev, next); + } else { + prev->dep_next = NULL; + } +} + +void nghttp2_stream_dep_add(nghttp2_stream *dep_stream, + nghttp2_stream *stream) { + DEBUGF("stream: dep_add dep_stream(%p)=%d, stream(%p)=%d\n", dep_stream, + dep_stream->stream_id, stream, stream->stream_id); + + dep_stream->sum_dep_weight += stream->weight; + + if (dep_stream->dep_next == NULL) { + link_dep(dep_stream, stream); + } else { + insert_link_dep(dep_stream, stream); + } + + validate_tree(stream); +} + +int nghttp2_stream_dep_remove(nghttp2_stream *stream) { + nghttp2_stream *dep_prev, *si; + int32_t sum_dep_weight_delta; + int rv; + + DEBUGF("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; + + if (si->queued) { + rv = stream_obq_move(stream->dep_prev, stream, si); + if (rv != 0) { + return rv; + } + } + } + + assert(stream->dep_prev); + + dep_prev = stream->dep_prev; + + dep_prev->sum_dep_weight += sum_dep_weight_delta; + + if (stream->queued) { + stream_obq_remove(stream); + } + + if (stream->sib_prev) { + unlink_sib(stream); + } else { + unlink_dep(stream); + } + + stream->sum_dep_weight = 0; + + stream->dep_prev = NULL; + stream->dep_next = NULL; + stream->sib_prev = NULL; + stream->sib_next = NULL; + + validate_tree(dep_prev); + + return 0; +} + +int nghttp2_stream_dep_insert_subtree(nghttp2_stream *dep_stream, + nghttp2_stream *stream) { + nghttp2_stream *last_sib; + nghttp2_stream *dep_next; + nghttp2_stream *si; + int rv; + + DEBUGF("stream: dep_insert_subtree 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) { + dep_next = dep_stream->dep_next; + + link_dep(dep_stream, stream); + + if (stream->dep_next) { + last_sib = stream_last_sib(stream->dep_next); + + link_sib(last_sib, dep_next); + } else { + link_dep(stream, dep_next); + } + + for (si = dep_next; si; si = si->sib_next) { + si->dep_prev = stream; + if (si->queued) { + rv = stream_obq_move(stream, dep_stream, si); + if (rv != 0) { + return rv; + } + } + } + } else { + link_dep(dep_stream, stream); + } + + if (stream_subtree_active(stream)) { + rv = stream_obq_push(dep_stream, stream); + if (rv != 0) { + return rv; + } + } + + validate_tree(dep_stream); + + return 0; +} + +int nghttp2_stream_dep_add_subtree(nghttp2_stream *dep_stream, + nghttp2_stream *stream) { + int rv; + + DEBUGF("stream: dep_add_subtree dep_stream(%p)=%d stream(%p)=%d\n", + dep_stream, dep_stream->stream_id, stream, stream->stream_id); + + dep_stream->sum_dep_weight += stream->weight; + + if (dep_stream->dep_next) { + insert_link_dep(dep_stream, stream); + } else { + link_dep(dep_stream, stream); + } + + if (stream_subtree_active(stream)) { + rv = stream_obq_push(dep_stream, stream); + if (rv != 0) { + return rv; + } + } + + validate_tree(dep_stream); + + return 0; +} + +void nghttp2_stream_dep_remove_subtree(nghttp2_stream *stream) { + nghttp2_stream *next, *dep_prev; + + DEBUGF("stream: dep_remove_subtree stream(%p)=%d\n", stream, + stream->stream_id); + + assert(stream->dep_prev); + + dep_prev = stream->dep_prev; + + if (stream->sib_prev) { + link_sib(stream->sib_prev, stream->sib_next); + } else { + next = stream->sib_next; + + link_dep(dep_prev, next); + + if (next) { + next->sib_prev = NULL; + } + } + + dep_prev->sum_dep_weight -= stream->weight; + + if (stream->queued) { + stream_obq_remove(stream); + } + + validate_tree(dep_prev); + + stream->sib_prev = NULL; + stream->sib_next = NULL; + stream->dep_prev = NULL; +} + +int nghttp2_stream_in_dep_tree(nghttp2_stream *stream) { + return stream->dep_prev || stream->dep_next || stream->sib_prev || + stream->sib_next; +} + +nghttp2_outbound_item * +nghttp2_stream_next_outbound_item(nghttp2_stream *stream) { + nghttp2_pq_entry *ent; + nghttp2_stream *si; + + for (;;) { + if (stream_active(stream)) { + /* Update ascendant's descendant_last_cycle here, so that we can + assure that new stream is scheduled based on it. */ + for (si = stream; si->dep_prev; si = si->dep_prev) { + si->dep_prev->descendant_last_cycle = si->cycle; + } + return stream->item; + } + ent = nghttp2_pq_top(&stream->obq); + if (!ent) { + return NULL; + } + stream = nghttp2_struct_of(ent, nghttp2_stream, pq_entry); + } +} + +nghttp2_stream_proto_state nghttp2_stream_get_state(nghttp2_stream *stream) { + if (stream->flags & NGHTTP2_STREAM_FLAG_CLOSED) { + return NGHTTP2_STREAM_STATE_CLOSED; + } + + if (stream->flags & NGHTTP2_STREAM_FLAG_PUSH) { + if (stream->shut_flags & NGHTTP2_SHUT_RD) { + return NGHTTP2_STREAM_STATE_RESERVED_LOCAL; + } + + if (stream->shut_flags & NGHTTP2_SHUT_WR) { + return NGHTTP2_STREAM_STATE_RESERVED_REMOTE; + } + } + + if (stream->shut_flags & NGHTTP2_SHUT_RD) { + return NGHTTP2_STREAM_STATE_HALF_CLOSED_REMOTE; + } + + if (stream->shut_flags & NGHTTP2_SHUT_WR) { + return NGHTTP2_STREAM_STATE_HALF_CLOSED_LOCAL; + } + + if (stream->state == NGHTTP2_STREAM_IDLE) { + return NGHTTP2_STREAM_STATE_IDLE; + } + + return NGHTTP2_STREAM_STATE_OPEN; +} + +nghttp2_stream *nghttp2_stream_get_parent(nghttp2_stream *stream) { + return stream->dep_prev; +} + +nghttp2_stream *nghttp2_stream_get_next_sibling(nghttp2_stream *stream) { + return stream->sib_next; +} + +nghttp2_stream *nghttp2_stream_get_previous_sibling(nghttp2_stream *stream) { + return stream->sib_prev; +} + +nghttp2_stream *nghttp2_stream_get_first_child(nghttp2_stream *stream) { + return stream->dep_next; +} + +int32_t nghttp2_stream_get_weight(nghttp2_stream *stream) { + return stream->weight; +} + +int32_t nghttp2_stream_get_sum_dependency_weight(nghttp2_stream *stream) { + return stream->sum_dep_weight; +} + +int32_t nghttp2_stream_get_stream_id(nghttp2_stream *stream) { + return stream->stream_id; +} |