/* * 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 #endif /* HAVE_CONFIG_H */ #include #include "nghttp2_outbound_item.h" #include "nghttp2_map.h" #include "nghttp2_pq.h" #include "nghttp2_int.h" /* * Maximum number of streams in one dependency tree. */ #define NGHTTP2_MAX_DEP_TREE_LENGTH 100 /* * 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_ALL = NGHTTP2_HTTP_FLAG_METH_CONNECT | NGHTTP2_HTTP_FLAG_METH_HEAD | NGHTTP2_HTTP_FLAG_METH_OPTIONS, /* :path category */ /* path starts with "/" */ NGHTTP2_HTTP_FLAG_PATH_REGULAR = 1 << 10, /* path "*" */ NGHTTP2_HTTP_FLAG_PATH_ASTERISK = 1 << 11, /* scheme */ /* "http" or "https" scheme */ NGHTTP2_HTTP_FLAG_SCHEME_HTTP = 1 << 12, /* set if final response is expected */ NGHTTP2_HTTP_FLAG_EXPECT_FINAL_RESPONSE = 1 << 13, } nghttp2_http_flag; typedef enum { NGHTTP2_STREAM_DPRI_NONE = 0, NGHTTP2_STREAM_DPRI_NO_ITEM = 0x01, NGHTTP2_STREAM_DPRI_TOP = 0x02, NGHTTP2_STREAM_DPRI_REST = 0x04 } nghttp2_stream_dpri; struct nghttp2_stream_roots; typedef struct nghttp2_stream_roots nghttp2_stream_roots; struct nghttp2_stream; typedef struct nghttp2_stream nghttp2_stream; struct nghttp2_stream { /* Intrusive Map */ nghttp2_map_entry map_entry; /* 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; /* pointers to track dependency tree root streams. This is doubly-linked list and first element is pointed by roots->head. */ nghttp2_stream *root_prev, *root_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; /* pointer to roots, which tracks dependency tree roots */ nghttp2_stream_roots *roots; /* The arbitrary data provided by user for this stream. */ void *stream_user_data; /* Item to send */ nghttp2_outbound_item *item; /* stream ID */ int32_t stream_id; /* categorized priority of this stream. Only stream bearing NGHTTP2_STREAM_DPRI_TOP can send item. */ nghttp2_stream_dpri dpri; /* the number of streams in subtree */ size_t num_substreams; /* 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; /* effective weight of this stream in belonging dependency tree */ int32_t effective_weight; /* sum of weight (not effective_weight) of direct descendants */ int32_t sum_dep_weight; /* sum of weight of direct descendants which have at least one descendant with dpri == NGHTTP2_STREAM_DPRI_TOP. We use this value to calculate effective weight. */ int32_t sum_norest_weight; /* sum of weight of direct descendants whose dpri value is NGHTTP2_STREAM_DPRI_TOP */ int32_t sum_top_weight; nghttp2_stream_state state; /* 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; /* Content-Length of request/response body. -1 if unknown. */ int64_t content_length; /* Received body so far */ int64_t recv_content_length; /* status code from remote server */ int16_t status_code; /* Bitwise OR of zero or more nghttp2_http_flag values */ uint16_t http_flags; }; 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); 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, nghttp2_session *session); /* * 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. */ int nghttp2_stream_resume_deferred_item(nghttp2_stream *stream, uint8_t flags, nghttp2_session *session); /* * 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 the stream positioned in root of the dependency tree the * |stream| belongs to. */ nghttp2_stream *nghttp2_stream_get_dep_root(nghttp2_stream *stream); /* * Returns nonzero if |target| is found in subtree of |stream|. */ int nghttp2_stream_dep_subtree_find(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. The result * is computed using stream->weight rather than * stream->effective_weight. */ int32_t nghttp2_stream_dep_distributed_weight(nghttp2_stream *stream, int32_t weight); /* * Computes effective weight of a stream of the |weight| under the * |stream|. The result is computed using stream->effective_weight * rather than stream->weight. This function is used to determine * weight in dependency tree. */ int32_t nghttp2_stream_dep_distributed_effective_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->data| is NULL and no dpri members are changed in this * dependency tree. */ void 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->data| is NULL and no * dpri members are changed in this dependency tree. */ void nghttp2_stream_dep_add(nghttp2_stream *dep_stream, nghttp2_stream *stream); /* * Removes the |stream| from the current dependency tree. This * function assumes |stream->data| is NULL. */ void nghttp2_stream_dep_remove(nghttp2_stream *stream); /* * Attaches |item| to |stream|. Updates dpri members in this * dependency tree. * * 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, nghttp2_session *session); /* * Detaches |stream->item|. Updates dpri members in this dependency * tree. 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, nghttp2_session *session); /* * Makes the |stream| depend on the |dep_stream|. This dependency is * exclusive. Updates dpri members in this dependency tree. * * 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, nghttp2_session *session); /* * Makes the |stream| depend on the |dep_stream|. This dependency is * not exclusive. Updates dpri members in this dependency tree. * * 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, nghttp2_session *session); /* * Removes subtree whose root stream is |stream|. Removing subtree * does not change dpri values. 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); /* * Makes the |stream| as root. Updates dpri members in this * dependency tree. * * 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_make_root(nghttp2_stream *stream, nghttp2_session *session); /* * Makes the |stream| as root and all existing root streams become * direct children of |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_dep_all_your_stream_are_belong_to_us(nghttp2_stream *stream, nghttp2_session *session); /* * Returns nonzero if |stream| is in any dependency tree. */ int nghttp2_stream_in_dep_tree(nghttp2_stream *stream); struct nghttp2_stream_roots { nghttp2_stream *head; int32_t num_streams; }; void nghttp2_stream_roots_init(nghttp2_stream_roots *roots); void nghttp2_stream_roots_free(nghttp2_stream_roots *roots); void nghttp2_stream_roots_add(nghttp2_stream_roots *roots, nghttp2_stream *stream); void nghttp2_stream_roots_remove(nghttp2_stream_roots *roots, nghttp2_stream *stream); void nghttp2_stream_roots_remove_all(nghttp2_stream_roots *roots); #endif /* NGHTTP2_STREAM */