From 76865fa41c6d4795d136fa2aceb9c05483ef6c89 Mon Sep 17 00:00:00 2001 From: Mahavir Jain Date: Thu, 30 Dec 2021 14:36:19 +0530 Subject: [PATCH] Add sh2lib (HTTP2 + TLS abstraction) component --- sh2lib/CMakeLists.txt | 4 + sh2lib/LICENSE | 202 +++++++++++++++++++++ sh2lib/README.md | 4 + sh2lib/idf_component.yml | 6 + sh2lib/sh2lib.c | 370 +++++++++++++++++++++++++++++++++++++++ sh2lib/sh2lib.h | 268 ++++++++++++++++++++++++++++ 6 files changed, 854 insertions(+) create mode 100644 sh2lib/CMakeLists.txt create mode 100644 sh2lib/LICENSE create mode 100644 sh2lib/README.md create mode 100644 sh2lib/idf_component.yml create mode 100644 sh2lib/sh2lib.c create mode 100644 sh2lib/sh2lib.h diff --git a/sh2lib/CMakeLists.txt b/sh2lib/CMakeLists.txt new file mode 100644 index 0000000..2fe306d --- /dev/null +++ b/sh2lib/CMakeLists.txt @@ -0,0 +1,4 @@ +idf_component_register(SRCS "sh2lib.c" + INCLUDE_DIRS . + REQUIRES http_parser + PRIV_REQUIRES lwip esp-tls) diff --git a/sh2lib/LICENSE b/sh2lib/LICENSE new file mode 100644 index 0000000..d645695 --- /dev/null +++ b/sh2lib/LICENSE @@ -0,0 +1,202 @@ + + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + + TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + + 1. 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Here we write + * |data| with size |length| to the network and return the number of + * bytes actually written. See the documentation of + * nghttp2_send_callback for the details. + */ +static ssize_t callback_send_inner(struct sh2lib_handle *hd, const uint8_t *data, + size_t length) +{ + int rv = esp_tls_conn_write(hd->http2_tls, data, length); + if (rv <= 0) { + if (rv == ESP_TLS_ERR_SSL_WANT_READ || rv == ESP_TLS_ERR_SSL_WANT_WRITE) { + rv = NGHTTP2_ERR_WOULDBLOCK; + } else { + rv = NGHTTP2_ERR_CALLBACK_FAILURE; + } + } + return rv; +} + +static ssize_t callback_send(nghttp2_session *session, const uint8_t *data, + size_t length, int flags, void *user_data) +{ + int rv = 0; + struct sh2lib_handle *hd = user_data; + + int copy_offset = 0; + int pending_data = length; + + /* Send data in 1000 byte chunks */ + while (copy_offset != length) { + int chunk_len = pending_data > 1000 ? 1000 : pending_data; + int subrv = callback_send_inner(hd, data + copy_offset, chunk_len); + if (subrv <= 0) { + if (copy_offset == 0) { + /* If no data is transferred, send the error code */ + rv = subrv; + } + break; + } + copy_offset += subrv; + pending_data -= subrv; + rv += subrv; + } + return rv; +} + +/* + * The implementation of nghttp2_recv_callback type. Here we read data + * from the network and write them in |buf|. The capacity of |buf| is + * |length| bytes. Returns the number of bytes stored in |buf|. See + * the documentation of nghttp2_recv_callback for the details. + */ +static ssize_t callback_recv(nghttp2_session *session, uint8_t *buf, + size_t length, int flags, void *user_data) +{ + struct sh2lib_handle *hd = user_data; + int rv; + rv = esp_tls_conn_read(hd->http2_tls, (char *)buf, (int)length); + if (rv < 0) { + if (rv == ESP_TLS_ERR_SSL_WANT_READ || rv == ESP_TLS_ERR_SSL_WANT_WRITE) { + rv = NGHTTP2_ERR_WOULDBLOCK; + } else { + rv = NGHTTP2_ERR_CALLBACK_FAILURE; + } + } else if (rv == 0) { + rv = NGHTTP2_ERR_EOF; + } + return rv; +} + +const char *sh2lib_frame_type_str(int type) +{ + switch (type) { + case NGHTTP2_HEADERS: + return "HEADERS"; + break; + case NGHTTP2_RST_STREAM: + return "RST_STREAM"; + break; + case NGHTTP2_GOAWAY: + return "GOAWAY"; + break; + case NGHTTP2_DATA: + return "DATA"; + break; + case NGHTTP2_SETTINGS: + return "SETTINGS"; + break; + case NGHTTP2_PUSH_PROMISE: + return "PUSH_PROMISE"; + break; + case NGHTTP2_PING: + return "PING"; + break; + default: + return "other"; + break; + } +} + +static int callback_on_frame_send(nghttp2_session *session, + const nghttp2_frame *frame, void *user_data) +{ + ESP_LOGD(TAG, "[frame-send] frame type %s", sh2lib_frame_type_str(frame->hd.type)); + switch (frame->hd.type) { + case NGHTTP2_HEADERS: + if (nghttp2_session_get_stream_user_data(session, frame->hd.stream_id)) { + ESP_LOGD(TAG, "[frame-send] C ----------------------------> S (HEADERS)"); +#if DBG_FRAME_SEND + ESP_LOGD(TAG, "[frame-send] headers nv-len = %d", frame->headers.nvlen); + const nghttp2_nv *nva = frame->headers.nva; + size_t i; + for (i = 0; i < frame->headers.nvlen; ++i) { + ESP_LOGD(TAG, "[frame-send] %s : %s", nva[i].name, nva[i].value); + } +#endif + } + break; + } + return 0; +} + +static int callback_on_frame_recv(nghttp2_session *session, + const nghttp2_frame *frame, void *user_data) +{ + ESP_LOGD(TAG, "[frame-recv][sid: %d] frame type %s", frame->hd.stream_id, sh2lib_frame_type_str(frame->hd.type)); + if (frame->hd.type != NGHTTP2_DATA) { + return 0; + } + /* Subsequent processing only for data frame */ + sh2lib_frame_data_recv_cb_t data_recv_cb = nghttp2_session_get_stream_user_data(session, frame->hd.stream_id); + if (data_recv_cb) { + struct sh2lib_handle *h2 = user_data; + (*data_recv_cb)(h2, NULL, 0, DATA_RECV_FRAME_COMPLETE); + } + return 0; +} + +static int callback_on_stream_close(nghttp2_session *session, int32_t stream_id, + uint32_t error_code, void *user_data) +{ + + ESP_LOGD(TAG, "[stream-close][sid %d]", stream_id); + sh2lib_frame_data_recv_cb_t data_recv_cb = nghttp2_session_get_stream_user_data(session, stream_id); + if (data_recv_cb) { + struct sh2lib_handle *h2 = user_data; + (*data_recv_cb)(h2, NULL, 0, DATA_RECV_RST_STREAM); + } + return 0; +} + +static int callback_on_data_chunk_recv(nghttp2_session *session, uint8_t flags, + int32_t stream_id, const uint8_t *data, + size_t len, void *user_data) +{ + sh2lib_frame_data_recv_cb_t data_recv_cb; + ESP_LOGD(TAG, "[data-chunk][sid:%d]", stream_id); + data_recv_cb = nghttp2_session_get_stream_user_data(session, stream_id); + if (data_recv_cb) { + ESP_LOGD(TAG, "[data-chunk] C <---------------------------- S (DATA chunk)" + "%lu bytes", + (unsigned long int)len); + struct sh2lib_handle *h2 = user_data; + (*data_recv_cb)(h2, (char *)data, len, 0); + /* TODO: What to do with the return value: look for pause/abort */ + } + return 0; +} + +static int callback_on_header(nghttp2_session *session, const nghttp2_frame *frame, + const uint8_t *name, size_t namelen, const uint8_t *value, + size_t valuelen, uint8_t flags, void *user_data) +{ + ESP_LOGD(TAG, "[hdr-recv][sid:%d] %s : %s", frame->hd.stream_id, name, value); + return 0; +} + +static int do_http2_connect(struct sh2lib_handle *hd) +{ + int ret; + nghttp2_session_callbacks *callbacks; + nghttp2_session_callbacks_new(&callbacks); + nghttp2_session_callbacks_set_send_callback(callbacks, callback_send); + nghttp2_session_callbacks_set_recv_callback(callbacks, callback_recv); + nghttp2_session_callbacks_set_on_frame_send_callback(callbacks, callback_on_frame_send); + nghttp2_session_callbacks_set_on_frame_recv_callback(callbacks, callback_on_frame_recv); + nghttp2_session_callbacks_set_on_stream_close_callback(callbacks, callback_on_stream_close); + nghttp2_session_callbacks_set_on_data_chunk_recv_callback(callbacks, callback_on_data_chunk_recv); + nghttp2_session_callbacks_set_on_header_callback(callbacks, callback_on_header); + ret = nghttp2_session_client_new(&hd->http2_sess, callbacks, hd); + if (ret != 0) { + ESP_LOGE(TAG, "[sh2-connect] New http2 session failed"); + nghttp2_session_callbacks_del(callbacks); + return -1; + } + nghttp2_session_callbacks_del(callbacks); + + /* Create the SETTINGS frame */ + ret = nghttp2_submit_settings(hd->http2_sess, NGHTTP2_FLAG_NONE, NULL, 0); + if (ret != 0) { + ESP_LOGE(TAG, "[sh2-connect] Submit settings failed"); + return -1; + } + return 0; +} + +int sh2lib_connect(struct sh2lib_config_t *cfg, struct sh2lib_handle *hd) +{ + memset(hd, 0, sizeof(*hd)); + + if (cfg == NULL) { + ESP_LOGE(TAG, "[sh2-connect] pointer to sh2lib configurations cannot be NULL"); + goto error; + } + + const char *proto[] = {"h2", NULL}; + esp_tls_cfg_t tls_cfg = { + .alpn_protos = proto, + .cacert_buf = cfg->cacert_buf, + .cacert_bytes = cfg->cacert_bytes, + .non_block = true, + .timeout_ms = 10 * 1000, + }; + if ((hd->http2_tls = esp_tls_conn_http_new(cfg->uri, &tls_cfg)) == NULL) { + ESP_LOGE(TAG, "[sh2-connect] esp-tls connection failed"); + goto error; + } + struct http_parser_url u; + http_parser_url_init(&u); + http_parser_parse_url(cfg->uri, strlen(cfg->uri), 0, &u); + hd->hostname = strndup(&cfg->uri[u.field_data[UF_HOST].off], u.field_data[UF_HOST].len); + + /* HTTP/2 Connection */ + if (do_http2_connect(hd) != 0) { + ESP_LOGE(TAG, "[sh2-connect] HTTP2 Connection failed with %s", cfg->uri); + goto error; + } + + return 0; +error: + sh2lib_free(hd); + return -1; +} + +void sh2lib_free(struct sh2lib_handle *hd) +{ + if (hd->http2_sess) { + nghttp2_session_del(hd->http2_sess); + hd->http2_sess = NULL; + } + if (hd->http2_tls) { + esp_tls_conn_destroy(hd->http2_tls); + hd->http2_tls = NULL; + } + if (hd->hostname) { + free(hd->hostname); + hd->hostname = NULL; + } +} + +int sh2lib_execute(struct sh2lib_handle *hd) +{ + int ret; + ret = nghttp2_session_send(hd->http2_sess); + if (ret != 0) { + ESP_LOGE(TAG, "[sh2-execute] HTTP2 session send failed %d", ret); + return -1; + } + + ret = nghttp2_session_recv(hd->http2_sess); + if (ret != 0) { + ESP_LOGE(TAG, "[sh2-execute] HTTP2 session recv failed %d", ret); + return -1; + } + + return 0; +} + +int sh2lib_do_get_with_nv(struct sh2lib_handle *hd, const nghttp2_nv *nva, size_t nvlen, sh2lib_frame_data_recv_cb_t recv_cb) +{ + int ret = nghttp2_submit_request(hd->http2_sess, NULL, nva, nvlen, NULL, recv_cb); + if (ret < 0) { + ESP_LOGE(TAG, "[sh2-do-get] HEADERS call failed"); + return -1; + } + return ret; +} + +int sh2lib_do_get(struct sh2lib_handle *hd, const char *path, sh2lib_frame_data_recv_cb_t recv_cb) +{ + const nghttp2_nv nva[] = { SH2LIB_MAKE_NV(":method", "GET"), + SH2LIB_MAKE_NV(":scheme", "https"), + SH2LIB_MAKE_NV(":authority", hd->hostname), + SH2LIB_MAKE_NV(":path", path), + }; + return sh2lib_do_get_with_nv(hd, nva, sizeof(nva) / sizeof(nva[0]), recv_cb); +} + +ssize_t sh2lib_data_provider_cb(nghttp2_session *session, int32_t stream_id, uint8_t *buf, + size_t length, uint32_t *data_flags, + nghttp2_data_source *source, void *user_data) +{ + struct sh2lib_handle *h2 = user_data; + sh2lib_putpost_data_cb_t data_cb = source->ptr; + return (*data_cb)(h2, (char *)buf, length, data_flags); +} + +int sh2lib_do_putpost_with_nv(struct sh2lib_handle *hd, const nghttp2_nv *nva, size_t nvlen, + sh2lib_putpost_data_cb_t send_cb, + sh2lib_frame_data_recv_cb_t recv_cb) +{ + + nghttp2_data_provider sh2lib_data_provider; + sh2lib_data_provider.read_callback = sh2lib_data_provider_cb; + sh2lib_data_provider.source.ptr = send_cb; + int ret = nghttp2_submit_request(hd->http2_sess, NULL, nva, nvlen, &sh2lib_data_provider, recv_cb); + if (ret < 0) { + ESP_LOGE(TAG, "[sh2-do-putpost] HEADERS call failed"); + return -1; + } + return ret; +} + +int sh2lib_do_post(struct sh2lib_handle *hd, const char *path, + sh2lib_putpost_data_cb_t send_cb, + sh2lib_frame_data_recv_cb_t recv_cb) +{ + const nghttp2_nv nva[] = { SH2LIB_MAKE_NV(":method", "POST"), + SH2LIB_MAKE_NV(":scheme", "https"), + SH2LIB_MAKE_NV(":authority", hd->hostname), + SH2LIB_MAKE_NV(":path", path), + }; + return sh2lib_do_putpost_with_nv(hd, nva, sizeof(nva) / sizeof(nva[0]), send_cb, recv_cb); +} + +int sh2lib_do_put(struct sh2lib_handle *hd, const char *path, + sh2lib_putpost_data_cb_t send_cb, + sh2lib_frame_data_recv_cb_t recv_cb) +{ + const nghttp2_nv nva[] = { SH2LIB_MAKE_NV(":method", "PUT"), + SH2LIB_MAKE_NV(":scheme", "https"), + SH2LIB_MAKE_NV(":authority", hd->hostname), + SH2LIB_MAKE_NV(":path", path), + }; + return sh2lib_do_putpost_with_nv(hd, nva, sizeof(nva) / sizeof(nva[0]), send_cb, recv_cb); +} diff --git a/sh2lib/sh2lib.h b/sh2lib/sh2lib.h new file mode 100644 index 0000000..3b4ce65 --- /dev/null +++ b/sh2lib/sh2lib.h @@ -0,0 +1,268 @@ +/* + * SPDX-FileCopyrightText: 2027-2021 Espressif Systems (Shanghai) CO LTD + * + * SPDX-License-Identifier: Apache-2.0 + */ + +#pragma once + +#include "esp_tls.h" +#include + +#ifdef __cplusplus +extern "C" { +#endif + +/* + * This is a thin API wrapper over nghttp2 that offers simplified APIs for usage + * in the application. The intention of this wrapper is to act as a stepping + * stone to quickly get started with using the HTTP/2 client. Since the focus is + * on simplicity, not all the features of HTTP/2 are supported through this + * wrapper. Once you are fairly comfortable with nghttp2, feel free to directly + * use nghttp2 APIs or make changes to sh2lib.c for realising your objectives. + * + * TODO: + * - Allowing to query response code, content-type etc in the receive callback + * - A simple function for per-stream header callback + */ +/** + * @brief Handle for working with sh2lib APIs + */ +struct sh2lib_handle { + nghttp2_session *http2_sess; /*!< Pointer to the HTTP2 session handle */ + char *hostname; /*!< The hostname we are connected to */ + struct esp_tls *http2_tls; /*!< Pointer to the TLS session handle */ +}; + +/** + * @brief sh2lib configuration structure + */ +struct sh2lib_config_t { + const char *uri; /*!< Pointer to the URI that should be connected to */ + const unsigned char *cacert_buf; /*!< Pointer to the buffer containing CA certificate */ + unsigned int cacert_bytes; /*!< Size of the CA certifiacte pointed by cacert_buf */ +}; + +/** Flag indicating receive stream is reset */ +#define DATA_RECV_RST_STREAM 1 +/** Flag indicating frame is completely received */ +#define DATA_RECV_FRAME_COMPLETE 2 + +/** + * @brief Function Prototype for data receive callback + * + * This function gets called whenever data is received on any stream. The + * function is also called for indicating events like frame receive complete, or + * end of stream. The function may get called multiple times as long as data is + * received on the stream. + * + * @param[in] handle Pointer to the sh2lib handle. + * @param[in] data Pointer to a buffer that contains the data received. + * @param[in] len The length of valid data stored at the 'data' pointer. + * @param[in] flags Flags indicating whether the stream is reset (DATA_RECV_RST_STREAM) or + * this particularly frame is completely received + * DATA_RECV_FRAME_COMPLETE). + * + * @return The function should return 0 + */ +typedef int (*sh2lib_frame_data_recv_cb_t)(struct sh2lib_handle *handle, const char *data, size_t len, int flags); + +/** + * @brief Function Prototype for callback to send data in PUT/POST + * + * This function gets called whenever nghttp2 wishes to send data, like for + * PUT/POST requests to the server. The function keeps getting called until this + * function sets the flag NGHTTP2_DATA_FLAG_EOF to indicate end of data. + * + * @param[in] handle Pointer to the sh2lib handle. + * @param[out] data Pointer to a buffer that should contain the data to send. + * @param[in] len The maximum length of data that can be sent out by this function. + * @param[out] data_flags Pointer to the data flags. The NGHTTP2_DATA_FLAG_EOF + * should be set in the data flags to indicate end of new data. + * + * @return The function should return the number of valid bytes stored in the + * data pointer + */ +typedef int (*sh2lib_putpost_data_cb_t)(struct sh2lib_handle *handle, char *data, size_t len, uint32_t *data_flags); + +/** + * @brief Connect to a URI using HTTP/2 + * + * This API opens an HTTP/2 connection with the provided URI. If successful, the + * hd pointer is populated with a valid handle for subsequent communication. + * + * Only 'https' URIs are supported. + * + * @param[in] cfg Pointer to the sh2lib configurations of the type 'struct sh2lib_config_t'. + * @param[out] hd Pointer to a variable of the type 'struct sh2lib_handle'. + * @return + * - ESP_OK if the connection was successful + * - ESP_FAIL if the connection fails + */ +int sh2lib_connect(struct sh2lib_config_t *cfg, struct sh2lib_handle *hd); + +/** + * @brief Free a sh2lib handle + * + * This API frees-up an sh2lib handle, thus closing any open connections that + * may be associated with this handle, and freeing up any resources. + * + * @param[in] hd Pointer to a variable of the type 'struct sh2lib_handle'. + * + */ +void sh2lib_free(struct sh2lib_handle *hd); + +/** + * @brief Setup an HTTP GET request stream + * + * This API sets up an HTTP GET request to be sent out to the server. A new + * stream is created for handling the request. Once the request is setup, the + * API sh2lib_execute() must be called to actually perform the socket I/O with + * the server. + * + * @param[in] hd Pointer to a variable of the type 'struct sh2lib_handle'. + * @param[in] path Pointer to the string that contains the resource to + * perform the HTTP GET operation on (for example, /users). + * @param[in] recv_cb The callback function that should be called for + * processing the request's response + * + * @return + * - ESP_OK if request setup is successful + * - ESP_FAIL if the request setup fails + */ +int sh2lib_do_get(struct sh2lib_handle *hd, const char *path, sh2lib_frame_data_recv_cb_t recv_cb); + +/** + * @brief Setup an HTTP POST request stream + * + * This API sets up an HTTP POST request to be sent out to the server. A new + * stream is created for handling the request. Once the request is setup, the + * API sh2lib_execute() must be called to actually perform the socket I/O with + * the server. + * + * @param[in] hd Pointer to a variable of the type 'struct sh2lib_handle'. + * @param[in] path Pointer to the string that contains the resource to + * perform the HTTP POST operation on (for example, /users). + * @param[in] send_cb The callback function that should be called for + * sending data as part of this request. + * @param[in] recv_cb The callback function that should be called for + * processing the request's response + * + * @return + * - ESP_OK if request setup is successful + * - ESP_FAIL if the request setup fails + */ +int sh2lib_do_post(struct sh2lib_handle *hd, const char *path, + sh2lib_putpost_data_cb_t send_cb, + sh2lib_frame_data_recv_cb_t recv_cb); + +/** + * @brief Setup an HTTP PUT request stream + * + * This API sets up an HTTP PUT request to be sent out to the server. A new + * stream is created for handling the request. Once the request is setup, the + * API sh2lib_execute() must be called to actually perform the socket I/O with + * the server. + * + * @param[in] hd Pointer to a variable of the type 'struct sh2lib_handle'. + * @param[in] path Pointer to the string that contains the resource to + * perform the HTTP PUT operation on (for example, /users). + * @param[in] send_cb The callback function that should be called for + * sending data as part of this request. + * @param[in] recv_cb The callback function that should be called for + * processing the request's response + * + * @return + * - ESP_OK if request setup is successful + * - ESP_FAIL if the request setup fails + */ +int sh2lib_do_put(struct sh2lib_handle *hd, const char *path, + sh2lib_putpost_data_cb_t send_cb, + sh2lib_frame_data_recv_cb_t recv_cb); + +/** + * @brief Execute send/receive on an HTTP/2 connection + * + * While the API sh2lib_do_get(), sh2lib_do_post() setup the requests to be + * initiated with the server, this API performs the actual data send/receive + * operations on the HTTP/2 connection. The callback functions are accordingly + * called during the processing of these requests. + * + * @param[in] hd Pointer to a variable of the type 'struct sh2lib_handle' + * + * @return + * - ESP_OK if the connection was successful + * - ESP_FAIL if the connection fails + */ +int sh2lib_execute(struct sh2lib_handle *hd); + +#define SH2LIB_MAKE_NV(NAME, VALUE) \ + { \ + (uint8_t *)NAME, (uint8_t *)VALUE, strlen(NAME), strlen(VALUE), \ + NGHTTP2_NV_FLAG_NONE \ + } + +/** + * @brief Setup an HTTP GET request stream with custom name-value pairs + * + * For a simpler version of the API, please refer to sh2lib_do_get(). + * + * This API sets up an HTTP GET request to be sent out to the server. A new + * stream is created for handling the request. Once the request is setup, the + * API sh2lib_execute() must be called to actually perform the socket I/O with + * the server. + * + * Please note that the following name value pairs MUST be a part of the request + * - name:value + * - ":method":"GET" + * - ":scheme":"https" + * - ":path": (for example, /users) + * + * @param[in] hd Pointer to a variable of the type 'struct sh2lib_handle'. + * @param[in] nva An array of name-value pairs that should be part of the request. + * @param[in] nvlen The number of elements in the array pointed to by 'nva'. + * @param[in] recv_cb The callback function that should be called for + * processing the request's response + * + * @return + * - ESP_OK if request setup is successful + * - ESP_FAIL if the request setup fails + */ +int sh2lib_do_get_with_nv(struct sh2lib_handle *hd, const nghttp2_nv *nva, size_t nvlen, sh2lib_frame_data_recv_cb_t recv_cb); + +/** + * @brief Setup an HTTP PUT/POST request stream with custom name-value pairs + * + * For a simpler version of the API, please refer to sh2lib_do_put() or + * sh2lib_do_post(). + * + * This API sets up an HTTP PUT/POST request to be sent out to the server. A new + * stream is created for handling the request. Once the request is setup, the + * API sh2lib_execute() must be called to actually perform the socket I/O with + * the server. + * + * Please note that the following name value pairs MUST be a part of the request + * - name:value + * - ":method":"PUT" (or POST) + * - ":scheme":"https" + * - ":path": (for example, /users) + * + * @param[in] hd Pointer to a variable of the type 'struct sh2lib_handle'. + * @param[in] nva An array of name-value pairs that should be part of the request. + * @param[in] nvlen The number of elements in the array pointed to by 'nva'. + * @param[in] send_cb The callback function that should be called for + * sending data as part of this request. + * @param[in] recv_cb The callback function that should be called for + * processing the request's response + * + * @return + * - ESP_OK if request setup is successful + * - ESP_FAIL if the request setup fails + */ +int sh2lib_do_putpost_with_nv(struct sh2lib_handle *hd, const nghttp2_nv *nva, size_t nvlen, + sh2lib_putpost_data_cb_t send_cb, + sh2lib_frame_data_recv_cb_t recv_cb); + +#ifdef __cplusplus +} +#endif