1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
|
/*
* 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.
*/
#ifndef NGHTTP2_STREAM_H
#define NGHTTP2_STREAM_H
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif /* HAVE_CONFIG_H */
#include <nghttp2/nghttp2.h>
#include "nghttp2_outbound_item.h"
#include "nghttp2_map.h"
#include "nghttp2_pq.h"
#include "nghttp2_int.h"
/*
* If local peer is stream initiator:
* NGHTTP2_STREAM_OPENING : upon sending request HEADERS
* NGHTTP2_STREAM_OPENED : upon receiving response HEADERS
* NGHTTP2_STREAM_CLOSING : upon queuing RST_STREAM
*
* If remote peer is stream initiator:
* NGHTTP2_STREAM_OPENING : upon receiving request HEADERS
* NGHTTP2_STREAM_OPENED : upon sending response HEADERS
* NGHTTP2_STREAM_CLOSING : upon queuing RST_STREAM
*/
typedef enum {
/* Initial state */
NGHTTP2_STREAM_INITIAL,
/* For stream initiator: request HEADERS has been sent, but response
HEADERS has not been received yet. For receiver: request HEADERS
has been received, but it does not send response HEADERS yet. */
NGHTTP2_STREAM_OPENING,
/* For stream initiator: response HEADERS is received. For receiver:
response HEADERS is sent. */
NGHTTP2_STREAM_OPENED,
/* RST_STREAM is received, but somehow we need to keep stream in
memory. */
NGHTTP2_STREAM_CLOSING,
/* PUSH_PROMISE is received or sent */
NGHTTP2_STREAM_RESERVED,
/* Stream is created in this state if it is used as anchor in
dependency tree. */
NGHTTP2_STREAM_IDLE
} nghttp2_stream_state;
typedef enum {
NGHTTP2_SHUT_NONE = 0,
/* Indicates further receptions will be disallowed. */
NGHTTP2_SHUT_RD = 0x01,
/* Indicates further transmissions will be disallowed. */
NGHTTP2_SHUT_WR = 0x02,
/* Indicates both further receptions and transmissions will be
disallowed. */
NGHTTP2_SHUT_RDWR = NGHTTP2_SHUT_RD | NGHTTP2_SHUT_WR
} nghttp2_shut_flag;
typedef enum {
NGHTTP2_STREAM_FLAG_NONE = 0,
/* Indicates that this stream is pushed stream and not opened
yet. */
NGHTTP2_STREAM_FLAG_PUSH = 0x01,
/* Indicates that this stream was closed */
NGHTTP2_STREAM_FLAG_CLOSED = 0x02,
/* Indicates the item is deferred due to flow control. */
NGHTTP2_STREAM_FLAG_DEFERRED_FLOW_CONTROL = 0x04,
/* Indicates the item is deferred by user callback */
NGHTTP2_STREAM_FLAG_DEFERRED_USER = 0x08,
/* bitwise OR of NGHTTP2_STREAM_FLAG_DEFERRED_FLOW_CONTROL and
NGHTTP2_STREAM_FLAG_DEFERRED_USER. */
NGHTTP2_STREAM_FLAG_DEFERRED_ALL = 0x0c
} nghttp2_stream_flag;
/* HTTP related flags to enforce HTTP semantics */
typedef enum {
NGHTTP2_HTTP_FLAG_NONE = 0,
/* header field seen so far */
NGHTTP2_HTTP_FLAG__AUTHORITY = 1,
NGHTTP2_HTTP_FLAG__PATH = 1 << 1,
NGHTTP2_HTTP_FLAG__METHOD = 1 << 2,
NGHTTP2_HTTP_FLAG__SCHEME = 1 << 3,
/* host is not pseudo header, but we require either host or
:authority */
NGHTTP2_HTTP_FLAG_HOST = 1 << 4,
NGHTTP2_HTTP_FLAG__STATUS = 1 << 5,
/* required header fields for HTTP request except for CONNECT
method. */
NGHTTP2_HTTP_FLAG_REQ_HEADERS = NGHTTP2_HTTP_FLAG__METHOD |
NGHTTP2_HTTP_FLAG__PATH |
NGHTTP2_HTTP_FLAG__SCHEME,
NGHTTP2_HTTP_FLAG_PSEUDO_HEADER_DISALLOWED = 1 << 6,
/* HTTP method flags */
NGHTTP2_HTTP_FLAG_METH_CONNECT = 1 << 7,
NGHTTP2_HTTP_FLAG_METH_HEAD = 1 << 8,
NGHTTP2_HTTP_FLAG_METH_OPTIONS = 1 << 9,
NGHTTP2_HTTP_FLAG_METH_UPGRADE_WORKAROUND = 1 << 10,
NGHTTP2_HTTP_FLAG_METH_ALL = NGHTTP2_HTTP_FLAG_METH_CONNECT |
NGHTTP2_HTTP_FLAG_METH_HEAD |
NGHTTP2_HTTP_FLAG_METH_OPTIONS |
NGHTTP2_HTTP_FLAG_METH_UPGRADE_WORKAROUND,
/* :path category */
/* path starts with "/" */
NGHTTP2_HTTP_FLAG_PATH_REGULAR = 1 << 11,
/* path "*" */
NGHTTP2_HTTP_FLAG_PATH_ASTERISK = 1 << 12,
/* scheme */
/* "http" or "https" scheme */
NGHTTP2_HTTP_FLAG_SCHEME_HTTP = 1 << 13,
/* set if final response is expected */
NGHTTP2_HTTP_FLAG_EXPECT_FINAL_RESPONSE = 1 << 14
} nghttp2_http_flag;
struct nghttp2_stream {
/* Intrusive Map */
nghttp2_map_entry map_entry;
/* Entry for dep_prev->obq */
nghttp2_pq_entry pq_entry;
/* Priority Queue storing direct descendant (nghttp2_stream). Only
streams which itself has some data to send, or has a descendant
which has some data to sent. */
nghttp2_pq obq;
/* Content-Length of request/response body. -1 if unknown. */
int64_t content_length;
/* Received body so far */
int64_t recv_content_length;
/* Base last_cycle for direct descendent streams. */
uint32_t descendant_last_cycle;
/* Next scheduled time to sent item */
uint32_t cycle;
/* Next seq used for direct descendant streams */
uint64_t descendant_next_seq;
/* Secondary key for prioritization to break a tie for cycle. This
value is monotonically increased for single parent stream. */
uint64_t seq;
/* pointers to form dependency tree. If multiple streams depend on
a stream, only one stream (left most) has non-NULL dep_prev which
points to the stream it depends on. The remaining streams are
linked using sib_prev and sib_next. The stream which has
non-NULL dep_prev always NULL sib_prev. The right most stream
has NULL sib_next. If this stream is a root of dependency tree,
dep_prev and sib_prev are NULL. */
nghttp2_stream *dep_prev, *dep_next;
nghttp2_stream *sib_prev, *sib_next;
/* When stream is kept after closure, it may be kept in doubly
linked list pointed by nghttp2_session closed_stream_head.
closed_next points to the next stream object if it is the element
of the list. */
nghttp2_stream *closed_prev, *closed_next;
/* The arbitrary data provided by user for this stream. */
void *stream_user_data;
/* Item to send */
nghttp2_outbound_item *item;
/* Last written length of frame payload */
size_t last_writelen;
/* stream ID */
int32_t stream_id;
/* Current remote window size. This value is computed against the
current initial window size of remote endpoint. */
int32_t remote_window_size;
/* Keep track of the number of bytes received without
WINDOW_UPDATE. This could be negative after submitting negative
value to WINDOW_UPDATE */
int32_t recv_window_size;
/* The number of bytes consumed by the application and now is
subject to WINDOW_UPDATE. This is only used when auto
WINDOW_UPDATE is turned off. */
int32_t consumed_size;
/* The amount of recv_window_size cut using submitting negative
value to WINDOW_UPDATE */
int32_t recv_reduction;
/* window size for local flow control. It is initially set to
NGHTTP2_INITIAL_WINDOW_SIZE and could be increased/decreased by
submitting WINDOW_UPDATE. See nghttp2_submit_window_update(). */
int32_t local_window_size;
/* weight of this stream */
int32_t weight;
/* This is unpaid penalty (offset) when calculating cycle. */
uint32_t pending_penalty;
/* sum of weight of direct descendants */
int32_t sum_dep_weight;
nghttp2_stream_state state;
/* status code from remote server */
int16_t status_code;
/* Bitwise OR of zero or more nghttp2_http_flag values */
uint16_t http_flags;
/* This is bitwise-OR of 0 or more of nghttp2_stream_flag. */
uint8_t flags;
/* Bitwise OR of zero or more nghttp2_shut_flag values */
uint8_t shut_flags;
/* Nonzero if this stream has been queued to stream pointed by
dep_prev. We maintain the invariant that if a stream is queued,
then its ancestors, except for root, are also queued. This
invariant may break in fatal error condition. */
uint8_t queued;
/* This flag is used to reduce excessive queuing of WINDOW_UPDATE to
this stream. The nonzero does not necessarily mean WINDOW_UPDATE
is not queued. */
uint8_t window_update_queued;
};
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);
void nghttp2_stream_free(nghttp2_stream *stream);
/*
* Disallow either further receptions or transmissions, or both.
* |flag| is bitwise OR of one or more of nghttp2_shut_flag.
*/
void nghttp2_stream_shutdown(nghttp2_stream *stream, nghttp2_shut_flag flag);
/*
* Defer |stream->item|. We won't call this function in the situation
* where |stream->item| == NULL. The |flags| is bitwise OR of zero or
* more of NGHTTP2_STREAM_FLAG_DEFERRED_USER and
* NGHTTP2_STREAM_FLAG_DEFERRED_FLOW_CONTROL. The |flags| indicates
* the reason of this action.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory
*/
int nghttp2_stream_defer_item(nghttp2_stream *stream, uint8_t flags);
/*
* Put back deferred data in this stream to active state. The |flags|
* are one or more of bitwise OR of the following values:
* NGHTTP2_STREAM_FLAG_DEFERRED_USER and
* NGHTTP2_STREAM_FLAG_DEFERRED_FLOW_CONTROL and given masks are
* cleared if they are set. So even if this function is called, if
* one of flag is still set, data does not become active.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory
*/
int nghttp2_stream_resume_deferred_item(nghttp2_stream *stream, uint8_t flags);
/*
* Returns nonzero if item is deferred by whatever reason.
*/
int nghttp2_stream_check_deferred_item(nghttp2_stream *stream);
/*
* Returns nonzero if item is deferred by flow control.
*/
int nghttp2_stream_check_deferred_by_flow_control(nghttp2_stream *stream);
/*
* Updates the remote window size with the new value
* |new_initial_window_size|. The |old_initial_window_size| is used to
* calculate the current window size.
*
* This function returns 0 if it succeeds or -1. The failure is due to
* overflow.
*/
int nghttp2_stream_update_remote_initial_window_size(
nghttp2_stream *stream, int32_t new_initial_window_size,
int32_t old_initial_window_size);
/*
* Updates the local window size with the new value
* |new_initial_window_size|. The |old_initial_window_size| is used to
* calculate the current window size.
*
* This function returns 0 if it succeeds or -1. The failure is due to
* overflow.
*/
int nghttp2_stream_update_local_initial_window_size(
nghttp2_stream *stream, int32_t new_initial_window_size,
int32_t old_initial_window_size);
/*
* Call this function if promised stream |stream| is replied with
* HEADERS. This function makes the state of the |stream| to
* NGHTTP2_STREAM_OPENED.
*/
void nghttp2_stream_promise_fulfilled(nghttp2_stream *stream);
/*
* Returns nonzero if |target| is an ancestor of |stream|.
*/
int nghttp2_stream_dep_find_ancestor(nghttp2_stream *stream,
nghttp2_stream *target);
/*
* Computes distributed weight of a stream of the |weight| under the
* |stream| if |stream| is removed from a dependency tree.
*/
int32_t nghttp2_stream_dep_distributed_weight(nghttp2_stream *stream,
int32_t weight);
/*
* Makes the |stream| depend on the |dep_stream|. This dependency is
* exclusive. All existing direct descendants of |dep_stream| become
* the descendants of the |stream|. This function assumes
* |stream->item| is NULL.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory
*/
int nghttp2_stream_dep_insert(nghttp2_stream *dep_stream,
nghttp2_stream *stream);
/*
* Makes the |stream| depend on the |dep_stream|. This dependency is
* not exclusive. This function assumes |stream->item| is NULL.
*/
void nghttp2_stream_dep_add(nghttp2_stream *dep_stream, nghttp2_stream *stream);
/*
* Removes the |stream| from the current dependency tree. This
* function assumes |stream->item| is NULL.
*/
int nghttp2_stream_dep_remove(nghttp2_stream *stream);
/*
* Attaches |item| to |stream|.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory
*/
int nghttp2_stream_attach_item(nghttp2_stream *stream,
nghttp2_outbound_item *item);
/*
* Detaches |stream->item|. This function does not free
* |stream->item|. The caller must free it.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory
*/
int nghttp2_stream_detach_item(nghttp2_stream *stream);
/*
* Makes the |stream| depend on the |dep_stream|. This dependency is
* exclusive.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory
*/
int nghttp2_stream_dep_insert_subtree(nghttp2_stream *dep_stream,
nghttp2_stream *stream);
/*
* Makes the |stream| depend on the |dep_stream|. This dependency is
* not exclusive.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory
*/
int nghttp2_stream_dep_add_subtree(nghttp2_stream *dep_stream,
nghttp2_stream *stream);
/*
* Removes subtree whose root stream is |stream|. The
* effective_weight of streams in removed subtree is not updated.
*
* This function returns 0 if it succeeds, or one of the following
* negative error codes:
*
* NGHTTP2_ERR_NOMEM
* Out of memory
*/
void nghttp2_stream_dep_remove_subtree(nghttp2_stream *stream);
/*
* Returns nonzero if |stream| is in any dependency tree.
*/
int nghttp2_stream_in_dep_tree(nghttp2_stream *stream);
/*
* Schedules transmission of |stream|'s item, assuming stream->item is
* attached, and stream->last_writelen was updated.
*/
void nghttp2_stream_reschedule(nghttp2_stream *stream);
/*
* Changes |stream|'s weight to |weight|. If |stream| is queued, it
* will be rescheduled based on new weight.
*/
void nghttp2_stream_change_weight(nghttp2_stream *stream, int32_t weight);
/*
* Returns a stream which has highest priority, updating
* descendant_last_cycle of selected stream's ancestors.
*/
nghttp2_outbound_item *
nghttp2_stream_next_outbound_item(nghttp2_stream *stream);
#endif /* NGHTTP2_STREAM */
|