new file mode 100644
--- /dev/null
+++ b/src/http/v3/ngx_http_v3_request.c
@@ -0,0 +1,971 @@
+
+/*
+ * Copyright (C) Roman Arutyunyan
+ * Copyright (C) Nginx, Inc.
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_http.h>
+
+
+#define NGX_HTTP_V3_FRAME_DATA          0x00
+#define NGX_HTTP_V3_FRAME_HEADERS       0x01
+#define NGX_HTTP_V3_FRAME_CANCEL_PUSH   0x03
+#define NGX_HTTP_V3_FRAME_SETTINGS      0x04
+#define NGX_HTTP_V3_FRAME_PUSH_PROMISE  0x05
+#define NGX_HTTP_V3_FRAME_GOAWAY        0x07
+#define NGX_HTTP_V3_FRAME_MAX_PUSH_ID   0x0d
+
+
+static ngx_int_t ngx_http_v3_process_pseudo_header(ngx_http_request_t *r,
+    ngx_str_t *name, ngx_str_t *value);
+
+
+struct {
+    ngx_str_t   name;
+    ngx_uint_t  method;
+} ngx_http_v3_methods[] = {
+
+    { ngx_string("GET"),       NGX_HTTP_GET },
+    { ngx_string("POST"),      NGX_HTTP_POST },
+    { ngx_string("HEAD"),      NGX_HTTP_HEAD },
+    { ngx_string("OPTIONS"),   NGX_HTTP_OPTIONS },
+    { ngx_string("PROPFIND"),  NGX_HTTP_PROPFIND },
+    { ngx_string("PUT"),       NGX_HTTP_PUT },
+    { ngx_string("MKCOL"),     NGX_HTTP_MKCOL },
+    { ngx_string("DELETE"),    NGX_HTTP_DELETE },
+    { ngx_string("COPY"),      NGX_HTTP_COPY },
+    { ngx_string("MOVE"),      NGX_HTTP_MOVE },
+    { ngx_string("PROPPATCH"), NGX_HTTP_PROPPATCH },
+    { ngx_string("LOCK"),      NGX_HTTP_LOCK },
+    { ngx_string("UNLOCK"),    NGX_HTTP_UNLOCK },
+    { ngx_string("PATCH"),     NGX_HTTP_PATCH },
+    { ngx_string("TRACE"),     NGX_HTTP_TRACE }
+};
+
+
+ngx_int_t
+ngx_http_v3_parse_header(ngx_http_request_t *r, ngx_buf_t *b, ngx_uint_t pseudo)
+{
+    u_char                *p, ch;
+    ngx_str_t              name, value;
+    ngx_int_t              rc;
+    ngx_uint_t             length, index, insert_count, sign, base, delta_base,
+                           huffman, dynamic, offset;
+    ngx_connection_t      *c;
+    ngx_http_v3_header_t  *h;
+    enum {
+        sw_start = 0,
+        sw_length,
+        sw_length_1,
+        sw_length_2,
+        sw_length_3,
+        sw_header_block,
+        sw_req_insert_count,
+        sw_delta_base,
+        sw_read_delta_base,
+        sw_header,
+        sw_old_header,
+        sw_header_ri,
+        sw_header_pbi,
+        sw_header_lri,
+        sw_header_lpbi,
+        sw_header_l_name_len,
+        sw_header_l_name,
+        sw_header_value_len,
+        sw_header_read_value_len,
+        sw_header_value
+    } state;
+
+    c = r->connection;
+
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                   "http3 parse header, pseudo:%ui", pseudo);
+
+    if (r->state == sw_old_header) {
+        r->state = sw_header;
+        return NGX_OK;
+    }
+
+    length = r->h3_length;
+    index = r->h3_index;
+    insert_count = r->h3_insert_count;
+    sign = r->h3_sign;
+    delta_base = r->h3_delta_base;
+    huffman = r->h3_huffman;
+    dynamic = r->h3_dynamic;
+    offset = r->h3_offset;
+
+    name.data = r->header_name_start;
+    name.len = r->header_name_end - r->header_name_start;
+    value.data = r->header_start;
+    value.len = r->header_end - r->header_start;
+
+    if (r->state == sw_start) {
+        length = 1;
+    }
+
+again:
+
+    state = r->state;
+
+    if (state == sw_header && length == 0) {
+        r->state = sw_start;
+        return NGX_HTTP_PARSE_HEADER_DONE;
+    }
+
+    for (p = b->pos; p < b->last; p++) {
+
+        if (state >= sw_header_block && length-- == 0) {
+            goto failed;
+        }
+
+        ch = *p;
+
+        switch (state) {
+
+        case sw_start:
+
+            if (ch != NGX_HTTP_V3_FRAME_HEADERS) {
+                goto failed;
+            }
+
+            r->request_start = p;
+            state = sw_length;
+            break;
+
+        case sw_length:
+
+            length = ch;
+            if (length & 0xc0) {
+                state = sw_length_1;
+                break;
+            }
+
+            state = sw_header_block;
+            break;
+
+        case sw_length_1:
+
+            length = (length << 8) + ch;
+            if ((length & 0xc000) != 0x4000) {
+                state = sw_length_2;
+                break;
+            }
+
+            length &= 0x3fff;
+            state = sw_header_block;
+            break;
+
+        case sw_length_2:
+
+            length = (length << 8) + ch;
+            if ((length & 0xc00000) != 0x800000) {
+                state = sw_length_3;
+                break;
+            }
+
+            /* fall through */
+
+        case sw_length_3:
+
+            length &= 0x3fffff;
+            state = sw_header_block;
+            break;
+
+        case sw_header_block:
+
+            ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                           "http3 header block length:%ui", length);
+
+            if (ch != 0xff) {
+                insert_count = ch;
+                state = sw_delta_base;
+                break;
+            }
+
+            insert_count = 0;
+            state = sw_req_insert_count;
+            break;
+
+        case sw_req_insert_count:
+
+            insert_count = (insert_count << 7) + (ch & 0x7f);
+            if (ch & 0x80) {
+                break;
+            }
+
+            insert_count += 0xff;
+            state = sw_delta_base;
+            break;
+
+        case sw_delta_base:
+
+            sign = (ch & 0x80) ? 1 : 0;
+            delta_base = ch & 0x7f;
+
+            if (delta_base != 0x7f) {
+                ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                               "http3 header block "
+                               "insert_count:%ui, sign:%ui, delta_base:%ui",
+                               insert_count, sign, delta_base);
+                goto done;
+            }
+
+            delta_base = 0;
+            state = sw_read_delta_base;
+            break;
+
+        case sw_read_delta_base:
+
+            delta_base = (delta_base << 7) + (ch & 0x7f);
+            if (ch & 0x80) {
+                break;
+            }
+
+            delta_base += 0x7f;
+
+            ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                           "http3 header block "
+                           "insert_count:%ui, sign:%ui, delta_base:%ui",
+                           insert_count, sign, delta_base);
+            goto done;
+
+        case sw_header:
+
+            index = 0;
+            huffman = 0;
+            ngx_str_null(&name);
+            ngx_str_null(&value);
+
+            if (ch & 0x80) {
+                /* Indexed Header Field */
+
+                dynamic = (ch & 0x40) ? 0 : 1;
+                index = ch & 0x3f;
+
+                if (index != 0x3f) {
+                    goto done;
+                }
+
+                index = 0;
+                state = sw_header_ri;
+                break;
+            }
+
+            if (ch & 0x40) {
+                /* Literal Header Field With Name Reference */
+
+                dynamic = (ch & 0x10) ? 0 : 1;
+                index = ch & 0x0f;
+
+                if (index != 0x0f) {
+                    state = sw_header_value_len;
+                    break;
+                }
+
+                index = 0;
+                state = sw_header_lri;
+                break;
+            }
+
+            if (ch & 0x20) {
+                /* Literal Header Field Without Name Reference */
+
+                huffman = (ch & 0x08) ? 1 : 0;
+                name.len = ch & 0x07;
+
+                if (name.len == 0) {
+                    goto failed;
+                }
+
+                if (name.len != 0x07) {
+                    offset = 0;
+                    state = sw_header_l_name;
+                    break;
+                }
+
+                name.len = 0;
+                state = sw_header_l_name_len;
+                break;
+            }
+
+            if (ch & 10) {
+                /* Indexed Header Field With Post-Base Index */
+
+                dynamic = 2;
+                index = ch & 0x0f;
+
+                if (index != 0x0f) {
+                    goto done;
+                }
+
+                index = 0;
+                state = sw_header_pbi;
+                break;
+            }
+
+            /* Literal Header Field With Post-Base Name Reference */
+
+            dynamic = 2;
+            index = ch & 0x07;
+
+            if (index != 0x07) {
+                state = sw_header_value_len;
+                break;
+            }
+
+            index = 0;
+            state = sw_header_lpbi;
+            break;
+
+        case sw_header_ri:
+
+            index = (index << 7) + (ch & 0x7f);
+            if (ch & 0x80) {
+                break;
+            }
+
+            index += 0x3f;
+            goto done;
+
+        case sw_header_pbi:
+
+            index = (index << 7) + (ch & 0x7f);
+            if (ch & 0x80) {
+                break;
+            }
+
+            index += 0x0f;
+            goto done;
+
+        case sw_header_lri:
+
+            index = (index << 7) + (ch & 0x7f);
+            if (ch & 0x80) {
+                break;
+            }
+
+            index += 0x0f;
+            state = sw_header_value_len;
+            break;
+
+        case sw_header_lpbi:
+
+            index = (index << 7) + (ch & 0x7f);
+            if (ch & 0x80) {
+                break;
+            }
+
+            index += 0x07;
+            state = sw_header_value_len;
+            break;
+
+
+        case sw_header_l_name_len:
+
+            name.len = (name.len << 7) + (ch & 0x7f);
+            if (ch & 0x80) {
+                break;
+            }
+
+            name.len += 0x07;
+            offset = 0;
+            state = sw_header_l_name;
+            break;
+
+        case sw_header_l_name:
+            if (offset++ == 0) {
+                name.data = p;
+            }
+
+            if (offset != name.len) {
+                break;
+            }
+
+            if (huffman) {
+                if (ngx_http_v3_decode_huffman(c, &name) != NGX_OK) {
+                    goto failed;
+                }
+            }
+
+            state = sw_header_value_len;
+            break;
+
+        case sw_header_value_len:
+
+            huffman = (ch & 0x80) ? 1 : 0;
+            value.len = ch & 0x7f;
+
+            if (value.len == 0) {
+                value.data = p;
+                goto done;
+            }
+
+            if (value.len != 0x7f) {
+                offset = 0;
+                state = sw_header_value;
+                break;
+            }
+
+            value.len = 0;
+            state = sw_header_read_value_len;
+            break;
+
+        case sw_header_read_value_len:
+
+            value.len = (value.len << 7) + (ch & 0x7f);
+            if (ch & 0x80) {
+                break;
+            }
+
+            value.len += 0x7f;
+            offset = 0;
+            state = sw_header_value;
+            break;
+
+        case sw_header_value:
+
+            if (offset++ == 0) {
+                value.data = p;
+            }
+
+            if (offset != value.len) {
+                break;
+            }
+
+            if (huffman) {
+                if (ngx_http_v3_decode_huffman(c, &value) != NGX_OK) {
+                    goto failed;
+                }
+            }
+
+            goto done;
+
+        case sw_old_header:
+
+            break;
+        }
+    }
+
+    b->pos = p;
+    r->state = state;
+    r->h3_length = length;
+    r->h3_index = index;
+    r->h3_insert_count = insert_count;
+    r->h3_sign = sign;
+    r->h3_delta_base = delta_base;
+    r->h3_huffman = huffman;
+    r->h3_dynamic = dynamic;
+    r->h3_offset = offset;
+
+    /* XXX fix large reallocations */
+    r->header_name_start = name.data;
+    r->header_name_end = name.data + name.len;
+    r->header_start = value.data;
+    r->header_end = value.data + value.len;
+
+    /* XXX r->lowcase_index = i; */
+
+    return NGX_AGAIN;
+
+done:
+
+    b->pos = p + 1;
+    r->state = sw_header;
+    r->h3_length = length;
+    r->h3_insert_count = insert_count;
+    r->h3_sign = sign;
+    r->h3_delta_base = delta_base;
+
+    if (state < sw_header) {
+        if (ngx_http_v3_check_insert_count(c, insert_count) != NGX_OK) {
+            return NGX_DONE;
+        }
+
+        goto again;
+    }
+
+    if (sign == 0) {
+        base = insert_count + delta_base;
+    } else {
+        base = insert_count - delta_base - 1;
+    }
+
+    ngx_log_debug5(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                   "http3 header %s[%ui], base:%ui, \"%V\":\"%V\"",
+                   dynamic ? "dynamic" : "static", index, base, &name, &value);
+
+    if (name.data == NULL) {
+
+        if (dynamic == 2) {
+            index = base - index - 1;
+        } else if (dynamic == 1) {
+            index += base;
+        }
+
+        h = ngx_http_v3_lookup_table(c, dynamic, index);
+        if (h == NULL) {
+            goto failed;
+        }
+
+        name = h->name;
+
+        if (value.data == NULL) {
+            value = h->value;
+        }
+    }
+
+    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                   "http3 header \"%V\":\"%V\"", &name, &value);
+
+    if (pseudo) {
+        rc = ngx_http_v3_process_pseudo_header(r, &name, &value);
+
+        if (rc == NGX_ERROR) {
+            goto failed;
+        }
+
+        if (rc == NGX_OK) {
+            r->request_end = p + 1;
+            goto again;
+        }
+
+        /* rc == NGX_DONE */
+
+        r->state = sw_old_header;
+    }
+
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                   "http3 header left:%ui", length);
+
+    r->header_name_start = name.data;
+    r->header_name_end = name.data + name.len;
+    r->header_start = value.data;
+    r->header_end = value.data + value.len;
+    r->header_hash = ngx_hash_key(name.data, name.len); /* XXX */
+
+    /* XXX r->lowcase_index = i; */
+
+    return NGX_OK;
+
+failed:
+
+    return NGX_HTTP_PARSE_INVALID_REQUEST;
+}
+
+
+static ngx_int_t
+ngx_http_v3_process_pseudo_header(ngx_http_request_t *r, ngx_str_t *name,
+    ngx_str_t *value)
+{
+    ngx_uint_t         i;
+    ngx_connection_t  *c;
+
+    c = r->connection;
+
+    if (name->len == 7 && ngx_strncmp(name->data, ":method", 7) == 0) {
+        r->method_start = value->data;
+        r->method_end = value->data + value->len;
+
+        for (i = 0; i < sizeof(ngx_http_v3_methods)
+                        / sizeof(ngx_http_v3_methods[0]); i++)
+        {
+            if (value->len == ngx_http_v3_methods[i].name.len
+                && ngx_strncmp(value->data, ngx_http_v3_methods[i].name.data,
+                               value->len) == 0)
+            {
+                r->method = ngx_http_v3_methods[i].method;
+                break;
+            }
+        }
+
+        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                       "http3 method \"%V\" %ui", value, r->method);
+        return NGX_OK;
+    }
+
+    if (name->len == 5 && ngx_strncmp(name->data, ":path", 5) == 0) {
+        r->uri_start = value->data;
+        r->uri_end = value->data + value->len;
+
+        if (ngx_http_parse_uri(r) != NGX_OK) {
+            ngx_log_error(NGX_LOG_INFO, c->log, 0,
+                          "client sent invalid :path header: \"%V\"", value);
+            return NGX_ERROR;
+        }
+
+        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                       "http3 path \"%V\"", value);
+
+        return NGX_OK;
+    }
+
+    if (name->len == 7 && ngx_strncmp(name->data, ":scheme", 7) == 0) {
+        r->schema_start = value->data;
+        r->schema_end = value->data + value->len;
+
+        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                       "http3 schema \"%V\"", value);
+
+        return NGX_OK;
+    }
+
+    if (name->len == 10 && ngx_strncmp(name->data, ":authority", 10) == 0) {
+        r->host_start = value->data;
+        r->host_end = value->data + value->len;
+
+        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                       "http3 authority \"%V\"", value);
+
+        return NGX_OK;
+    }
+
+    if (name->len && name->data[0] == ':') {
+        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                       "http3 unknown pseudo header \"%V\" \"%V\"",
+                       name, value);
+        return NGX_OK;
+    }
+
+    return NGX_DONE;
+}
+
+
+ngx_chain_t *
+ngx_http_v3_create_header(ngx_http_request_t *r)
+{
+    u_char                    *p;
+    size_t                     len, hlen, n;
+    ngx_buf_t                 *b;
+    ngx_uint_t                 i, j;
+    ngx_chain_t               *hl, *cl, *bl;
+    ngx_list_part_t           *part;
+    ngx_table_elt_t           *header;
+    ngx_connection_t          *c;
+    ngx_http_core_loc_conf_t  *clcf;
+
+    c = r->connection;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 create header");
+
+    /* XXX support chunked body in the chunked filter */
+    if (r->headers_out.content_length_n == -1) {
+        return NULL;
+    }
+
+    len = 0;
+
+    if (r->headers_out.status == NGX_HTTP_OK) {
+        len += ngx_http_v3_encode_prefix_int(NULL, 25, 6);
+
+    } else {
+        len += 3 + ngx_http_v3_encode_prefix_int(NULL, 25, 4)
+                 + ngx_http_v3_encode_prefix_int(NULL, 3, 7);
+    }
+
+    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
+
+    if (r->headers_out.server == NULL) {
+        if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_ON) {
+            n = sizeof(NGINX_VER) - 1;
+
+        } else if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_BUILD) {
+            n = sizeof(NGINX_VER_BUILD) - 1;
+
+        } else {
+            n = sizeof("nginx") - 1;
+        }
+
+        len += ngx_http_v3_encode_prefix_int(NULL, 92, 4)
+               + ngx_http_v3_encode_prefix_int(NULL, n, 7) + n;
+    }
+
+    if (r->headers_out.date == NULL) {
+        len += ngx_http_v3_encode_prefix_int(NULL, 6, 4)
+               + ngx_http_v3_encode_prefix_int(NULL, ngx_cached_http_time.len,
+                                               7)
+               + ngx_cached_http_time.len;
+    }
+
+    if (r->headers_out.content_type.len) {
+        n = r->headers_out.content_type.len;
+
+        if (r->headers_out.content_type_len == r->headers_out.content_type.len
+            && r->headers_out.charset.len)
+        {
+            n += sizeof("; charset=") - 1 + r->headers_out.charset.len;
+        }
+
+        len += ngx_http_v3_encode_prefix_int(NULL, 53, 4)
+               + ngx_http_v3_encode_prefix_int(NULL, n, 7) + n;
+    }
+
+    if (r->headers_out.content_length_n == 0) {
+        len += ngx_http_v3_encode_prefix_int(NULL, 4, 6);
+
+    } else {
+        len += ngx_http_v3_encode_prefix_int(NULL, 4, 4) + 1 + NGX_OFF_T_LEN;
+    }
+
+    if (r->headers_out.last_modified == NULL
+        && r->headers_out.last_modified_time != -1)
+    {
+        len += ngx_http_v3_encode_prefix_int(NULL, 10, 4) + 1
+               + sizeof("Last-Modified: Mon, 28 Sep 1970 06:00:00 GMT");
+    }
+
+    /* XXX location */
+
+#if (NGX_HTTP_GZIP)
+    if (r->gzip_vary) {
+        if (clcf->gzip_vary) {
+            /* Vary: Accept-Encoding */
+            len += ngx_http_v3_encode_prefix_int(NULL, 59, 6);
+
+        } else {
+            r->gzip_vary = 0;
+        }
+    }
+#endif
+
+    part = &r->headers_out.headers.part;
+    header = part->elts;
+
+    for (i = 0; /* void */; i++) {
+
+        if (i >= part->nelts) {
+            if (part->next == NULL) {
+                break;
+            }
+
+            part = part->next;
+            header = part->elts;
+            i = 0;
+        }
+
+        if (header[i].hash == 0) {
+            continue;
+        }
+
+        len += ngx_http_v3_encode_prefix_int(NULL, header[i].key.len, 3)
+               + header[i].key.len
+               + ngx_http_v3_encode_prefix_int(NULL, header[i].value.len, 7 )
+               + header[i].value.len;
+    }
+
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 header len:%uz", len);
+
+    b = ngx_create_temp_buf(r->pool, len);
+    if (b == NULL) {
+        return NULL;
+    }
+
+    *b->last++ = 0;
+    *b->last++ = 0;
+
+    if (r->headers_out.status == NGX_HTTP_OK) {
+        /* :status: 200 */
+        *b->last = 0xc0;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last, 25, 6);
+
+    } else {
+        /* :status: 200 */
+        *b->last = 0x70;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last, 25, 4);
+        *b->last = 0;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last, 3, 7);
+        b->last = ngx_sprintf(b->last, "%03ui ", r->headers_out.status);
+    }
+
+    if (r->headers_out.server == NULL) {
+        if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_ON) {
+            p = (u_char *) NGINX_VER;
+            n = sizeof(NGINX_VER) - 1;
+
+        } else if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_BUILD) {
+            p = (u_char *) NGINX_VER_BUILD;
+            n = sizeof(NGINX_VER_BUILD) - 1;
+
+        } else {
+            p = (u_char *) "nginx";
+            n = sizeof("nginx") - 1;
+        }
+
+        /* server */
+        *b->last = 0x70;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last, 92, 4);
+        *b->last = 0;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last, n, 7);
+        b->last = ngx_cpymem(b->last, p, n);
+    }
+
+    if (r->headers_out.date == NULL) {
+        /* date */
+        *b->last = 0x70;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last, 6, 4);
+        *b->last = 0;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last,
+                                                 ngx_cached_http_time.len, 7);
+        b->last = ngx_cpymem(b->last, ngx_cached_http_time.data,
+                             ngx_cached_http_time.len);
+    }
+
+    if (r->headers_out.content_type.len) {
+        n = r->headers_out.content_type.len;
+
+        if (r->headers_out.content_type_len == r->headers_out.content_type.len
+            && r->headers_out.charset.len)
+        {
+            n += sizeof("; charset=") - 1 + r->headers_out.charset.len;
+        }
+
+        /* content-type: text/plain */
+        *b->last = 0x70;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last, 53, 4);
+        *b->last = 0;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last, n, 7);
+
+        p = b->last;
+        b->last = ngx_copy(b->last, r->headers_out.content_type.data,
+                           r->headers_out.content_type.len);
+
+        if (r->headers_out.content_type_len == r->headers_out.content_type.len
+            && r->headers_out.charset.len)
+        {
+            b->last = ngx_cpymem(b->last, "; charset=",
+                                 sizeof("; charset=") - 1);
+            b->last = ngx_copy(b->last, r->headers_out.charset.data,
+                               r->headers_out.charset.len);
+
+            /* update r->headers_out.content_type for possible logging */
+
+            r->headers_out.content_type.len = b->last - p;
+            r->headers_out.content_type.data = p;
+        }
+    }
+
+    if (r->headers_out.content_length_n == 0) {
+        /* content-length: 0 */
+        *b->last = 0xc0;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last, 4, 6);
+
+    } else if (r->headers_out.content_length_n > 0) {
+        /* content-length: 0 */
+        *b->last = 0x70;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last, 4, 4);
+        p = b->last++;
+        b->last = ngx_sprintf(b->last, "%O", r->headers_out.content_length_n);
+        *p = b->last - p - 1;
+    }
+
+    if (r->headers_out.last_modified == NULL
+        && r->headers_out.last_modified_time != -1)
+    {
+        /* last-modified */
+        *b->last = 0x70;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last, 10, 4);
+        p = b->last++;
+        b->last = ngx_http_time(b->last, r->headers_out.last_modified_time);
+        *p = b->last - p - 1;
+    }
+
+#if (NGX_HTTP_GZIP)
+    if (r->gzip_vary) {
+        /* vary: accept-encoding */
+        *b->last = 0xc0;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last, 59, 6);
+    }
+#endif
+
+    part = &r->headers_out.headers.part;
+    header = part->elts;
+
+    for (i = 0; /* void */; i++) {
+
+        if (i >= part->nelts) {
+            if (part->next == NULL) {
+                break;
+            }
+
+            part = part->next;
+            header = part->elts;
+            i = 0;
+        }
+
+        if (header[i].hash == 0) {
+            continue;
+        }
+
+        *b->last = 0x30;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last,
+                                                           header[i].key.len,
+                                                           3);
+        for (j = 0; j < header[i].key.len; j++) {
+            *b->last++ = ngx_tolower(header[i].key.data[j]);
+        }
+
+        *b->last = 0;
+        b->last = (u_char *) ngx_http_v3_encode_prefix_int(b->last,
+                                                           header[i].value.len,
+                                                           7);
+        b->last = ngx_copy(b->last, header[i].value.data, header[i].value.len);
+    }
+
+    cl = ngx_alloc_chain_link(c->pool);
+    if (cl == NULL) {
+        return NULL;
+    }
+
+    cl->buf = b;
+    cl->next = NULL;
+
+    n = b->last - b->pos;
+
+    len = 1 + ngx_http_v3_encode_varlen_int(NULL, n);
+
+    b = ngx_create_temp_buf(c->pool, len);
+    if (b == NULL) {
+        return NULL;
+    }
+
+    *b->last++ = NGX_HTTP_V3_FRAME_HEADERS;
+    b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, n);
+
+    hl = ngx_alloc_chain_link(c->pool);
+    if (hl == NULL) {
+        return NULL;
+    }
+
+    hl->buf = b;
+    hl->next = cl;
+
+    hlen = 1 + ngx_http_v3_encode_varlen_int(NULL, len);
+
+    if (r->headers_out.content_length_n >= 0) {
+        len = 1 + ngx_http_v3_encode_varlen_int(NULL,
+                                              r->headers_out.content_length_n);
+
+        b = ngx_create_temp_buf(c->pool, len);
+        if (b == NULL) {
+            NULL;
+        }
+
+        *b->last++ = NGX_HTTP_V3_FRAME_DATA;
+        b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last,
+                                              r->headers_out.content_length_n);
+
+        bl = ngx_alloc_chain_link(c->pool);
+        if (bl == NULL) {
+            return NULL;
+        }
+
+        bl->buf = b;
+        bl->next = NULL;
+        cl->next = bl;
+    }
+
+    return hl;
+}