589 lines
22 KiB
C
589 lines
22 KiB
C
/*
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* nghttp2 - HTTP/2.0 C Library
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*
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* Copyright (c) 2012 Tatsuhiro Tsujikawa
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*
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* Permission is hereby granted, free of charge, to any person obtaining
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* a copy of this software and associated documentation files (the
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* "Software"), to deal in the Software without restriction, including
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* without limitation the rights to use, copy, modify, merge, publish,
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* distribute, sublicense, and/or sell copies of the Software, and to
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* permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice shall be
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* included in all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
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* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
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* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
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* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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*/
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#ifndef NGHTTP2_FRAME_H
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#define NGHTTP2_FRAME_H
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#ifdef HAVE_CONFIG_H
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# include <config.h>
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#endif /* HAVE_CONFIG_H */
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#include <nghttp2/nghttp2.h>
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#include "nghttp2_hd.h"
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#include "nghttp2_buffer.h"
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#define NGHTTP2_FRAME_LENGTH_MASK ((1 << 14) - 1)
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#define NGHTTP2_STREAM_ID_MASK ((1u << 31) - 1)
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#define NGHTTP2_PRIORITY_MASK ((1u << 31) - 1)
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#define NGHTTP2_WINDOW_SIZE_INCREMENT_MASK ((1u << 31) - 1)
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#define NGHTTP2_SETTINGS_ID_MASK ((1 << 24) - 1)
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/* The maximum payload length of a frame */
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#define NGHTTP2_MAX_FRAME_LENGTH ((1 << 14) - 1)
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/* The maximum length of DATA frame payload. */
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#define NGHTTP2_DATA_PAYLOAD_LENGTH 4096
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/* The number of bytes of frame header. */
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#define NGHTTP2_FRAME_HEAD_LENGTH 8
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/* The number of bytes for each SETTINGS entry */
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#define NGHTTP2_FRAME_SETTINGS_ENTRY_LENGTH 5
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/* Category of frames. */
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typedef enum {
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/* non-DATA frame */
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NGHTTP2_CAT_CTRL,
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/* DATA frame */
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NGHTTP2_CAT_DATA
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} nghttp2_frame_category;
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/**
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* @struct
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*
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* The DATA frame used in the library privately. It has the following
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* members:
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*/
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typedef struct {
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nghttp2_frame_hd hd;
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/**
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* The data to be sent for this DATA frame.
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*/
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nghttp2_data_provider data_prd;
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/**
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* The number of bytes added as padding. This includes PAD_HIGH and
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* PAD_LOW.
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*/
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size_t padlen;
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/**
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* The flag to indicate whether EOF was reached or not. Initially
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* |eof| is 0. It becomes 1 after all data were read. This is used
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* exclusively by nghttp2 library and not in the spec.
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*/
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uint8_t eof;
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} nghttp2_private_data;
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int nghttp2_frame_is_data_frame(uint8_t *head);
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void nghttp2_frame_pack_frame_hd(uint8_t *buf, const nghttp2_frame_hd *hd);
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void nghttp2_frame_unpack_frame_hd(nghttp2_frame_hd *hd, const uint8_t* buf);
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/*
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* Returns the offset from the HEADERS frame payload where the
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* compressed header block starts. The frame payload does not include
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* frame header.
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*/
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size_t nghttp2_frame_headers_payload_nv_offset(nghttp2_headers *frame);
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/*
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* Packs HEADERS frame |frame| in wire format and store it in
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* |*buf_ptr|. The capacity of |*buf_ptr| is |*buflen_ptr| bytes.
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* This function expands |*buf_ptr| as necessary to store frame. When
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* expansion occurred, memory previously pointed by |*buf_ptr| may
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* change. |*buf_ptr| and |*buflen_ptr| are updated accordingly.
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*
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* The first byte the frame is serialized is returned in the
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* |*bufoff_ptr|. Currently, it is always 2 to account for possible
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* PAD_HIGH and PAD_LOW.
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*
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* frame->hd.length is assigned after length is determined during
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* packing process. If payload length is strictly larger than
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* NGHTTP2_MAX_FRAME_LENGTH, payload data is still serialized as is,
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* but frame->hd.length is set to NGHTTP2_MAX_FRAME_LENGTH and
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* NGHTTP2_FLAG_END_HEADERS flag is cleared from frame->hd.flags.
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*
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* This function returns the size of packed frame (which includes
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* |*bufoff_ptr| bytes) if it succeeds, or returns one of the
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* following negative error codes:
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*
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* NGHTTP2_ERR_HEADER_COMP
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* The deflate operation failed.
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* NGHTTP2_ERR_FRAME_TOO_LARGE
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* The length of the frame is too large.
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* NGHTTP2_ERR_NOMEM
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* Out of memory.
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*/
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ssize_t nghttp2_frame_pack_headers(uint8_t **buf_ptr,
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size_t *buflen_ptr,
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size_t *bufoff_ptr,
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nghttp2_headers *frame,
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nghttp2_hd_deflater *deflater);
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/*
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* Unpacks HEADERS frame byte sequence into |frame|. This function
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* only unapcks bytes that come before name/value header block.
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*
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* This function returns 0 if it succeeds or one of the following
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* negative error codes:
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*
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* NGHTTP2_ERR_PROTO
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* TODO END_HEADERS flag is not set
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*/
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int nghttp2_frame_unpack_headers_payload(nghttp2_headers *frame,
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const uint8_t *payload,
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size_t payloadlen);
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/*
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* Packs PRIORITY frame |frame| in wire format and store it in
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* |*buf_ptr|. The capacity of |*buf_ptr| is |*buflen_ptr|
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* length. This function expands |*buf_ptr| as necessary to store
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* given |frame|.
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*
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* This function returns 0 if it succeeds or one of the following
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* negative error codes:
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*
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* NGHTTP2_ERR_NOMEM
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* Out of memory.
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*/
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ssize_t nghttp2_frame_pack_priority(uint8_t **buf_ptr, size_t *buflen_ptr,
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nghttp2_priority *frame);
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/*
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* Unpacks PRIORITY wire format into |frame|.
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*/
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void nghttp2_frame_unpack_priority_payload(nghttp2_priority *frame,
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const uint8_t *payload,
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size_t payloadlen);
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/*
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* Packs RST_STREAM frame |frame| in wire frame format and store it in
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* |*buf_ptr|. The capacity of |*buf_ptr| is |*buflen_ptr|
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* length. This function expands |*buf_ptr| as necessary to store
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* given |frame|. In spdy/2 spec, RST_STREAM wire format is always 16
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* bytes long.
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*
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* This function returns the size of packed frame if it succeeds, or
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* returns one of the following negative error codes:
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*
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* NGHTTP2_ERR_NOMEM
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* Out of memory.
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*/
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ssize_t nghttp2_frame_pack_rst_stream(uint8_t **buf_ptr, size_t *buflen_ptr,
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nghttp2_rst_stream *frame);
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/*
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* Unpacks RST_STREAM frame byte sequence into |frame|.
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*/
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void nghttp2_frame_unpack_rst_stream_payload(nghttp2_rst_stream *frame,
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const uint8_t *payload,
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size_t payloadlen);
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/*
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* Packs SETTINGS frame |frame| in wire format and store it in
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* |*buf_ptr|. The capacity of |*buf_ptr| is |*buflen_ptr|
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* length. This function expands |*buf_ptr| as necessary to store
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* given |frame|.
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*
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* This function returns the size of packed frame if it succeeds, or
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* returns one of the following negative error codes:
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*
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* NGHTTP2_ERR_NOMEM
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* Out of memory.
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*/
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ssize_t nghttp2_frame_pack_settings(uint8_t **buf_ptr, size_t *buflen_ptr,
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nghttp2_settings *frame);
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/*
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* Packs the |iv|, which includes |niv| entries, in the |buf|,
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* assuming the |buf| has at least 8 * |niv| bytes.
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*
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* Returns the number of bytes written into the |buf|.
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*/
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size_t nghttp2_frame_pack_settings_payload(uint8_t *buf,
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const nghttp2_settings_entry *iv,
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size_t niv);
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void nghttp2_frame_unpack_settings_entry(nghttp2_settings_entry *iv,
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const uint8_t *payload);
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/*
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* Makes a copy of |iv| in frame->settings.iv. The |niv| is assigned
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* to frame->settings.niv.
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*
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* This function returns 0 if it succeeds or one of the following
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* negative error codes:
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*
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* NGHTTP2_ERR_NOMEM
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* Out of memory.
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*/
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int nghttp2_frame_unpack_settings_payload(nghttp2_settings *frame,
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nghttp2_settings_entry *iv,
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size_t niv);
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/*
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* Unpacks SETTINGS payload into |*iv_ptr|. The number of entries are
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* assigned to the |*niv_ptr|. This function allocates enough memory
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* to store the result in |*iv_ptr|. The caller is responsible to free
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* |*iv_ptr| after its use.
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*
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* This function returns 0 if it succeeds or one of the following
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* negative error codes:
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*
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* NGHTTP2_ERR_NOMEM
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* Out of memory.
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*/
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int nghttp2_frame_unpack_settings_payload2(nghttp2_settings_entry **iv_ptr,
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size_t *niv_ptr,
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const uint8_t *payload,
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size_t payloadlen);
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/*
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* Packs PUSH_PROMISE frame |frame| in wire format and store it in
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* |*buf_ptr|. The capacity of |*buf_ptr| is |*buflen_ptr| bytes.
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* This function expands |*buf_ptr| as necessary to store frame. When
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* expansion occurred, memory previously pointed by |*buf_ptr| may
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* change. |*buf_ptr| and |*buflen_ptr| are updated accordingly.
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*
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* The first byte the frame is serialized is returned in the
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* |*bufoff_ptr|. Currently, it is always 2 to account for possible
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* PAD_HIGH and PAD_LOW.
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*
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* frame->hd.length is assigned after length is determined during
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* packing process. If payload length is strictly larger than
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* NGHTTP2_MAX_FRAME_LENGTH, payload data is still serialized as is,
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* but frame->hd.length is set to NGHTTP2_MAX_FRAME_LENGTH and
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* NGHTTP2_FLAG_END_HEADERS flag is cleared from frame->hd.flags.
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*
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* This function returns the size of packed frame (which includes
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* |*bufoff_ptr| bytes) if it succeeds, or returns one of the
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* following negative error codes:
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*
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* This function returns the size of packed frame if it succeeds, or
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* returns one of the following negative error codes:
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*
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* NGHTTP2_ERR_HEADER_COMP
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* The deflate operation failed.
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* NGHTTP2_ERR_FRAME_TOO_LARGE
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* The length of the frame is too large.
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* NGHTTP2_ERR_NOMEM
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* Out of memory.
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*/
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ssize_t nghttp2_frame_pack_push_promise(uint8_t **buf_ptr,
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size_t *buflen_ptr,
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size_t *bufoff_ptr,
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nghttp2_push_promise *frame,
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nghttp2_hd_deflater *deflater);
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/*
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* Unpacks PUSH_PROMISE frame byte sequence into |frame|. This function
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* only unapcks bytes that come before name/value header block.
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*
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* This function returns 0 if it succeeds or one of the following
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* negative error codes:
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*
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* NGHTTP2_ERR_PROTO
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* TODO END_HEADERS flag is not set
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*/
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int nghttp2_frame_unpack_push_promise_payload(nghttp2_push_promise *frame,
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const uint8_t *payload,
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size_t payloadlen);
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/*
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* Packs PING frame |frame| in wire format and store it in
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* |*buf_ptr|. The capacity of |*buf_ptr| is |*buflen_ptr|
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* length. This function expands |*buf_ptr| as necessary to store
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* given |frame|.
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*
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* This function returns 0 if it succeeds or one of the following
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* negative error codes:
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*
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* NGHTTP2_ERR_NOMEM
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* Out of memory.
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*/
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ssize_t nghttp2_frame_pack_ping(uint8_t **buf_ptr, size_t *buflen_ptr,
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nghttp2_ping *frame);
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/*
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* Unpacks PING wire format into |frame|.
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*/
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void nghttp2_frame_unpack_ping_payload(nghttp2_ping *frame,
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const uint8_t *payload,
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size_t payloadlen);
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/*
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* Packs GOAWAY frame |frame | in wire format and store it in
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* |*buf_ptr|. The capacity of |*buf_ptr| is |*buflen_ptr|
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* length. This function expands |*buf_ptr| as necessary to store
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* given |frame|.
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*
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* This function returns 0 if it succeeds or one of the following
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* negative error codes:
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*
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* NGHTTP2_ERR_NOMEM
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* Out of memory.
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*/
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ssize_t nghttp2_frame_pack_goaway(uint8_t **buf_ptr, size_t *buflen_ptr,
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nghttp2_goaway *frame);
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/*
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* Unpacks GOAWAY wire format into |frame|.
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*/
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void nghttp2_frame_unpack_goaway_payload(nghttp2_goaway *frame,
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const uint8_t *payload,
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size_t payloadlen);
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/*
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* Packs WINDOW_UPDATE frame |frame| in wire frame format and store it
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* in |*buf_ptr|. The capacity of |*buf_ptr| is |*buflen_ptr|
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* length. This function expands |*buf_ptr| as necessary to store
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* given |frame|.
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*
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* This function returns the size of packed frame if it succeeds, or
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* returns one of the following negative error codes:
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*
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* NGHTTP2_ERR_NOMEM
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* Out of memory.
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*/
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ssize_t nghttp2_frame_pack_window_update(uint8_t **buf_ptr, size_t *buflen_ptr,
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nghttp2_window_update *frame);
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/*
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* Unpacks WINDOW_UPDATE frame byte sequence into |frame|.
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*/
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void nghttp2_frame_unpack_window_update_payload(nghttp2_window_update *frame,
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const uint8_t *payload,
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size_t payloadlen);
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/*
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* Initializes HEADERS frame |frame| with given values. |frame| takes
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* ownership of |nva|, so caller must not free it. If |stream_id| is
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* not assigned yet, it must be -1.
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*/
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void nghttp2_frame_headers_init(nghttp2_headers *frame,
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uint8_t flags, int32_t stream_id, int32_t pri,
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nghttp2_nv *nva, size_t nvlen);
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void nghttp2_frame_headers_free(nghttp2_headers *frame);
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void nghttp2_frame_priority_init(nghttp2_priority *frame, int32_t stream_id,
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int32_t pri);
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void nghttp2_frame_priority_free(nghttp2_priority *frame);
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void nghttp2_frame_rst_stream_init(nghttp2_rst_stream *frame,
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int32_t stream_id,
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nghttp2_error_code error_code);
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void nghttp2_frame_rst_stream_free(nghttp2_rst_stream *frame);
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/*
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* Initializes PUSH_PROMISE frame |frame| with given values. |frame|
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* takes ownership of |nva|, so caller must not free it.
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*/
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void nghttp2_frame_push_promise_init(nghttp2_push_promise *frame,
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uint8_t flags, int32_t stream_id,
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int32_t promised_stream_id,
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nghttp2_nv *nva, size_t nvlen);
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void nghttp2_frame_push_promise_free(nghttp2_push_promise *frame);
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/*
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* Initializes SETTINGS frame |frame| with given values. |frame| takes
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* ownership of |iv|, so caller must not free it. The |flags| are
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* bitwise-OR of one or more of nghttp2_settings_flag.
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*/
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void nghttp2_frame_settings_init(nghttp2_settings *frame, uint8_t flags,
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nghttp2_settings_entry *iv, size_t niv);
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void nghttp2_frame_settings_free(nghttp2_settings *frame);
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/*
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* Initializes PING frame |frame| with given values. If the
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* |opqeue_data| is not NULL, it must point to 8 bytes memory region
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* of data. The data pointed by |opaque_data| is copied. It can be
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* NULL. In this case, 8 bytes NULL is used.
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*/
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void nghttp2_frame_ping_init(nghttp2_ping *frame, uint8_t flags,
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const uint8_t *opque_data);
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void nghttp2_frame_ping_free(nghttp2_ping *frame);
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/*
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* Initializes GOAWAY frame |frame| with given values. On success,
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* this function takes ownership of |opaque_data|, so caller must not
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* free it. If the |opaque_data_len| is 0, opaque_data could be NULL.
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*/
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void nghttp2_frame_goaway_init(nghttp2_goaway *frame, int32_t last_stream_id,
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nghttp2_error_code error_code,
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uint8_t *opaque_data, size_t opaque_data_len);
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void nghttp2_frame_goaway_free(nghttp2_goaway *frame);
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void nghttp2_frame_window_update_init(nghttp2_window_update *frame,
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uint8_t flags,
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int32_t stream_id,
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int32_t window_size_increment);
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void nghttp2_frame_window_update_free(nghttp2_window_update *frame);
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void nghttp2_frame_data_init(nghttp2_data *frame, nghttp2_private_data *pdata);
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/*
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* Returns the number of padding bytes after payload. The total
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* padding length is given in the |padlen|. The returned value does
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* not include the PAD_HIGH and PAD_LOW.
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*/
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size_t nghttp2_frame_trail_padlen(nghttp2_frame *frame, size_t padlen);
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void nghttp2_frame_private_data_init(nghttp2_private_data *frame,
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uint8_t flags,
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int32_t stream_id,
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const nghttp2_data_provider *data_prd);
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void nghttp2_frame_private_data_free(nghttp2_private_data *frame);
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/*
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* Makes copy of |iv| and return the copy. The |niv| is the number of
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* entries in |iv|. This function returns the pointer to the copy if
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* it succeeds, or NULL.
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*/
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nghttp2_settings_entry* nghttp2_frame_iv_copy(const nghttp2_settings_entry *iv,
|
|
size_t niv);
|
|
|
|
/*
|
|
* Sorts the |nva| in ascending order of name and value. If names are
|
|
* equivalent, sort them by value.
|
|
*/
|
|
void nghttp2_nv_array_sort(nghttp2_nv *nva, size_t nvlen);
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|
|
|
/*
|
|
* Copies name/value pairs from |nva|, which contains |nvlen| pairs,
|
|
* to |*nva_ptr|, which is dynamically allocated so that all items can
|
|
* be stored.
|
|
*
|
|
* The |*nva_ptr| must be freed using nghttp2_nv_array_del().
|
|
*
|
|
* This function returns the number of name/value pairs in |*nva_ptr|,
|
|
* or one of the following negative error codes:
|
|
*
|
|
* NGHTTP2_ERR_NOMEM
|
|
* Out of memory.
|
|
* NGHTTP2_ERR_INVALID_ARGUMENT
|
|
* The length of name or value in |nva| is strictly larger than
|
|
* NGHTTP2_MAX_HD_VALUE_LENGTH.
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|
*/
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|
ssize_t nghttp2_nv_array_copy(nghttp2_nv **nva_ptr,
|
|
const nghttp2_nv *nva, size_t nvlen);
|
|
|
|
/*
|
|
* Returns nonzero if the name/value pair |a| equals to |b|. The name
|
|
* is compared in case-sensitive, because we ensure that this function
|
|
* is called after the name is lower-cased.
|
|
*/
|
|
int nghttp2_nv_equal(const nghttp2_nv *a, const nghttp2_nv *b);
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|
|
|
/*
|
|
* Frees |nva|.
|
|
*/
|
|
void nghttp2_nv_array_del(nghttp2_nv *nva);
|
|
|
|
/*
|
|
* Checks that the |iv|, which includes |niv| entries, does not have
|
|
* invalid values.
|
|
*
|
|
* This function returns nonzero if it succeeds, or 0.
|
|
*/
|
|
int nghttp2_iv_check(const nghttp2_settings_entry *iv, size_t niv);
|
|
|
|
/*
|
|
* Add padding to the payload in the |*buf_ptr| of length
|
|
* |*buflen_ptr|. The payload length is given in |payloadlen|. The
|
|
* frame header starts at offset |*bufoff_ptr|. Therefore, the payload
|
|
* must start at offset *bufoff_ptr + NGHTTP2_FRAME_HEAD_LENGTH from
|
|
* |*buf_ptr| to account for PAD_HIGH and PAD_LOW. The padding is
|
|
* given in the |padlen|.
|
|
*
|
|
* The |*flags_ptr| is updated to include NGHTTP2_FLAG_PAD_LOW and
|
|
* NGHTTP2_FLAG_PAD_HIGH based on the padding length. The
|
|
* |*bufoff_ptr| will have the offset starting the frame header in
|
|
* |*buf_ptr|.
|
|
*
|
|
* The |*buf_ptr| and |*buflen_ptr| may be extended to include padding
|
|
* bytes.
|
|
*
|
|
* The padding specifier PAD_HIGH and PAD_LOW are located right after
|
|
* the frame header. But they may not be there depending of the length
|
|
* of the padding. To save the additional buffer copy, we allocate
|
|
* buffer size as if these 2 bytes always exist. Depending of the
|
|
* length of the padding, we move the location of frame header and
|
|
* adjust |*bufoff_ptr|. If more than or equal to 256 padding is made,
|
|
* the |*bufoff_ptr| is 0 and the content of the |*buf_ptr| looks like
|
|
* this:
|
|
*
|
|
* 0 1 2 3
|
|
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
|
|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
* | Frame header ...
|
|
* +---------------------------------------------------------------+
|
|
* . Frame header |
|
|
* +---------------+---------------+-------------------------------+
|
|
* | Pad high | Pad low | Payload ...
|
|
* +---------------+---------------+-------------------------------+
|
|
*
|
|
*
|
|
* If padding is less than 256 but strictly more than 0, the
|
|
* |*bufoff_ptr| is 1 and the |*buf_ptr| looks like this:
|
|
*
|
|
* 0 1 2 3
|
|
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
|
|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
* | Unused | Frame header ...
|
|
* +---------------+-----------------------------------------------+
|
|
* . Frame header ...
|
|
* +---------------+---------------+-------------------------------+
|
|
* . Frame Header | Pad low | Payload ...
|
|
* +---------------+---------------+-------------------------------+
|
|
*
|
|
* If no padding is added, the |*bufoff_ptr| is 2 and the |*buf_ptr|
|
|
* looks like this:
|
|
*
|
|
* 0 1 2 3
|
|
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
|
|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
* | Unused | Frame header ...
|
|
* +-------------------------------+-------------------------------+
|
|
* . Frame header ...
|
|
* +-------------------------------+-------------------------------+
|
|
* . Frame Header | Payload ...
|
|
* +-------------------------------+-------------------------------+
|
|
*
|
|
* Notice that the position of payload does not change. This way, we
|
|
* can set PAD_HIGH and PAD_LOW after payload was serialized and no
|
|
* additional copy operation is required (if the |*buf_ptr| is large
|
|
* enough to account the additional padding, of course).
|
|
*
|
|
* This function returns 0 if it succeeds, or one of the following
|
|
* negative error codes:
|
|
*
|
|
* NGHTTP2_ERR_NOMEM
|
|
* Out of memory.
|
|
*/
|
|
int nghttp2_frame_add_pad(uint8_t **buf_ptr, size_t *buflen_ptr,
|
|
size_t *bufoff_ptr, uint8_t *flags_ptr,
|
|
size_t payloadlen, size_t padlen);
|
|
|
|
#endif /* NGHTTP2_FRAME_H */
|