text: /*
  Copyright: Boaz Segev, 2017-2019
  License: MIT
  */
  #include <fio.h>
  
  #include <http1.h>
  #include <http1_parser.h>
  #include <http_internal.h>
  #include <websockets.h>
  
  #include <fiobj.h>
  
  #include <assert.h>
  #include <stddef.h>
  
  /* *****************************************************************************
  The HTTP/1.1 Protocol Object
  ***************************************************************************** */
  
  typedef struct http1pr_s {
    http_fio_protocol_s p;
    http1_parser_s parser;
    http_s request;
    uintptr_t buf_len;
    uintptr_t max_header_size;
    uintptr_t header_size;
    uint8_t close;
    uint8_t is_client;
    uint8_t stop;
    uint8_t buf[];
  } http1pr_s;
  
  struct http_vtable_s HTTP1_VTABLE; /* initialized later on */
  
  /* *****************************************************************************
  Internal Helpers
  ***************************************************************************** */
  
  #define parser2http(x)                                                         \
    ((http1pr_s *)((uintptr_t)(x) - (uintptr_t)(&((http1pr_s *)0)->parser)))
  
  inline static void h1_reset(http1pr_s *p) { p->header_size = 0; }
  
  #define http1_pr2handle(pr) (((http1pr_s *)(pr))->request)
  #define handle2pr(h) ((http1pr_s *)h->private_data.flag)
  
  static fio_str_info_s http1pr_status2str(uintptr_t status);
  
  /* cleanup an HTTP/1.1 handler object */
  static inline void http1_after_finish(http_s *h) {
    http1pr_s *p = handle2pr(h);
    p->stop = p->stop & (~1UL);
    if (h != &p->request) {
      http_s_destroy(h, 0);
      fio_free(h);
    } else {
      http_s_clear(h, p->p.settings->log);
    }
    if (p->close)
      fio_close(p->p.uuid);
  }
  
  /* *****************************************************************************
  HTTP Request / Response (Virtual) Functions
  ***************************************************************************** */
  struct header_writer_s {
    FIOBJ dest;
    FIOBJ name;
    FIOBJ value;
  };
  
  static int write_header(FIOBJ o, void *w_) {
    struct header_writer_s *w = w_;
    if (!o)
      return 0;
    if (fiobj_hash_key_in_loop()) {
      w->name = fiobj_hash_key_in_loop();
    }
    if (FIOBJ_TYPE_IS(o, FIOBJ_T_ARRAY)) {
      fiobj_each1(o, 0, write_header, w);
      return 0;
    }
    fio_str_info_s name = fiobj_obj2cstr(w->name);
    fio_str_info_s str = fiobj_obj2cstr(o);
    if (!str.data)
      return 0;
    // fiobj_str_capa_assert(w->dest,
    //                       fiobj_obj2cstr(w->dest).len + name.len + str.len +
    //                       5);
    fiobj_str_write(w->dest, name.data, name.len);
    fiobj_str_write(w->dest, ":", 1);
    fiobj_str_write(w->dest, str.data, str.len);
    fiobj_str_write(w->dest, "\r\n", 2);
    return 0;
  }
  
  static FIOBJ headers2str(http_s *h, uintptr_t padding) {
    if (!h->method && !!h->status_str)
      return FIOBJ_INVALID;
  
    static uintptr_t connection_hash;
    if (!connection_hash)
      connection_hash = fiobj_hash_string("connection", 10);
  
    struct header_writer_s w;
    {
      const uintptr_t header_length_guess =
          fiobj_hash_count(h->private_data.out_headers) * 64;
      w.dest = fiobj_str_buf(header_length_guess + padding);
    }
    http1pr_s *p = handle2pr(h);
  
    if (p->is_client == 0) {
      fio_str_info_s t = http1pr_status2str(h->status);
      fiobj_str_write(w.dest, t.data, t.len);
      FIOBJ tmp = fiobj_hash_get2(h->private_data.out_headers, connection_hash);
      if (tmp) {
        t = fiobj_obj2cstr(tmp);
        if (t.data[0] == 'c' || t.data[0] == 'C')
          p->close = 1;
      } else {
        tmp = fiobj_hash_get2(h->headers, connection_hash);
        if (tmp) {
          t = fiobj_obj2cstr(tmp);
          if (!t.data || !t.len || t.data[0] == 'k' || t.data[0] == 'K')
            fiobj_str_write(w.dest, "connection:keep-alive\r\n", 23);
          else {
            fiobj_str_write(w.dest, "connection:close\r\n", 18);
            p->close = 1;
          }
        } else {
          t = fiobj_obj2cstr(h->version);
          if (!p->close && t.len > 7 && t.data && t.data[5] == '1' &&
              t.data[6] == '.' && t.data[7] == '1')
            fiobj_str_write(w.dest, "connection:keep-alive\r\n", 23);
          else {
            fiobj_str_write(w.dest, "connection:close\r\n", 18);
            p->close = 1;
          }
        }
      }
    } else {
      if (h->method) {
        fiobj_str_join(w.dest, h->method);
        fiobj_str_write(w.dest, " ", 1);
      } else {
        fiobj_str_write(w.dest, "GET ", 4);
      }
      fiobj_str_join(w.dest, h->path);
      if (h->query) {
        fiobj_str_write(w.dest, "?", 1);
        fiobj_str_join(w.dest, h->query);
      }
      fiobj_str_write(w.dest, " HTTP/1.1\r\n", 11);
      /* make sure we have a host header? */
      static uint64_t host_hash;
      if (!host_hash)
        host_hash = fiobj_hash_string("host", 4);
      FIOBJ tmp;
      if (!fiobj_hash_get2(h->private_data.out_headers, host_hash) &&
          (tmp = fiobj_hash_get2(h->headers, host_hash))) {
        fiobj_str_write(w.dest, "host:", 5);
        fiobj_str_join(w.dest, tmp);
        fiobj_str_write(w.dest, "\r\n", 2);
      }
      if (!fiobj_hash_get2(h->private_data.out_headers, connection_hash))
        fiobj_str_write(w.dest, "connection:keep-alive\r\n", 23);
    }
  
    fiobj_each1(h->private_data.out_headers, 0, write_header, &w);
    fiobj_str_write(w.dest, "\r\n", 2);
    return w.dest;
  }
  
  /** Should send existing headers and data */
  static int http1_send_body(http_s *h, void *data, uintptr_t length) {
  
    FIOBJ packet = headers2str(h, length);
    if (!packet) {
      http1_after_finish(h);
      return -1;
    }
    fiobj_str_write(packet, data, length);
    fiobj_send_free((handle2pr(h)->p.uuid), packet);
    http1_after_finish(h);
    return 0;
  }
  /** Should send existing headers and file */
  static int http1_sendfile(http_s *h, int fd, uintptr_t length,
                            uintptr_t offset) {
    FIOBJ packet = headers2str(h, 0);
    if (!packet) {
      close(fd);
      http1_after_finish(h);
      return -1;
    }
    if (length < HTTP_MAX_HEADER_LENGTH) {
      /* optimize away small files */
      fio_str_info_s s = fiobj_obj2cstr(packet);
      fiobj_str_capa_assert(packet, s.len + length);
      s = fiobj_obj2cstr(packet);
      intptr_t i = pread(fd, s.data + s.len, length, offset);
      if (i < 0) {
        close(fd);
        fiobj_send_free((handle2pr(h)->p.uuid), packet);
        fio_close((handle2pr(h)->p.uuid));
        return -1;
      }
      close(fd);
      fiobj_str_resize(packet, s.len + i);
      fiobj_send_free((handle2pr(h)->p.uuid), packet);
      http1_after_finish(h);
      return 0;
    }
    fiobj_send_free((handle2pr(h)->p.uuid), packet);
    fio_sendfile((handle2pr(h)->p.uuid), fd, offset, length);
    http1_after_finish(h);
    return 0;
  }
  
  /** Should send existing headers or complete streaming */
  static void htt1p_finish(http_s *h) {
    FIOBJ packet = headers2str(h, 0);
    if (packet)
      fiobj_send_free((handle2pr(h)->p.uuid), packet);
    else {
      // fprintf(stderr, "WARNING: invalid call to `htt1p_finish`\n");
    }
    http1_after_finish(h);
  }
  /** Push for data - unsupported. */
  static int http1_push_data(http_s *h, void *data, uintptr_t length,
                             FIOBJ mime_type) {
    return -1;
    (void)h;
    (void)data;
    (void)length;
    (void)mime_type;
  }
  /** Push for files - unsupported. */
  static int http1_push_file(http_s *h, FIOBJ filename, FIOBJ mime_type) {
    return -1;
    (void)h;
    (void)filename;
    (void)mime_type;
  }
  
  /**
   * Called befor a pause task,
   */
  static void http1_on_pause(http_s *h, http_fio_protocol_s *pr) {
    ((http1pr_s *)pr)->stop = 1;
    fio_suspend(pr->uuid);
    (void)h;
  }
  
  /**
   * called after the resume task had completed.
   */
  static void http1_on_resume(http_s *h, http_fio_protocol_s *pr) {
    if (!((http1pr_s *)pr)->stop) {
      fio_force_event(pr->uuid, FIO_EVENT_ON_DATA);
    }
    (void)h;
  }
  
  static intptr_t http1_hijack(http_s *h, fio_str_info_s *leftover) {
    if (leftover) {
      intptr_t len =
          handle2pr(h)->buf_len -
          (intptr_t)(handle2pr(h)->parser.state.next - handle2pr(h)->buf);
      if (len) {
        *leftover = (fio_str_info_s){
            .len = len, .data = (char *)handle2pr(h)->parser.state.next};
      } else {
        *leftover = (fio_str_info_s){.len = 0, .data = NULL};
      }
    }
  
    handle2pr(h)->stop = 3;
    intptr_t uuid = handle2pr(h)->p.uuid;
    fio_attach(uuid, NULL);
    return uuid;
  }
  
  /* *****************************************************************************
  Websockets Upgrading
  ***************************************************************************** */
  
  static void http1_websocket_client_on_upgrade(http_s *h, char *proto,
                                                size_t len) {
    http1pr_s *p = handle2pr(h);
    websocket_settings_s *args = h->udata;
    const intptr_t uuid = handle2pr(h)->p.uuid;
    http_settings_s *set = handle2pr(h)->p.settings;
    set->udata = NULL;
    http_finish(h);
    p->stop = 1;
    websocket_attach(uuid, set, args, p->parser.state.next,
                     p->buf_len - (intptr_t)(p->parser.state.next - p->buf));
    fio_free(args);
    (void)proto;
    (void)len;
  }
  static void http1_websocket_client_on_failed(http_s *h) {
    websocket_settings_s *s = h->udata;
    if (s->on_close)
      s->on_close(0, s->udata);
    fio_free(h->udata);
    h->udata = http_settings(h)->udata = NULL;
  }
  static void http1_websocket_client_on_hangup(http_settings_s *settings) {
    websocket_settings_s *s = settings->udata;
    if (s) {
      if (s->on_close)
        s->on_close(0, s->udata);
      fio_free(settings->udata);
      settings->udata = NULL;
    }
  }
  
  static int http1_http2websocket_server(http_s *h, websocket_settings_s *args) {
    // A static data used for all websocket connections.
    static char ws_key_accpt_str[] = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
    static uintptr_t sec_version = 0;
    static uintptr_t sec_key = 0;
    if (!sec_version)
      sec_version = fiobj_hash_string("sec-websocket-version", 21);
    if (!sec_key)
      sec_key = fiobj_hash_string("sec-websocket-key", 17);
  
    FIOBJ tmp = fiobj_hash_get2(h->headers, sec_version);
    if (!tmp)
      goto bad_request;
    fio_str_info_s stmp = fiobj_obj2cstr(tmp);
    if (stmp.len != 2 || stmp.data[0] != '1' || stmp.data[1] != '3')
      goto bad_request;
  
    tmp = fiobj_hash_get2(h->headers, sec_key);
    if (!tmp)
      goto bad_request;
    stmp = fiobj_obj2cstr(tmp);
  
    fio_sha1_s sha1 = fio_sha1_init();
    fio_sha1_write(&sha1, stmp.data, stmp.len);
    fio_sha1_write(&sha1, ws_key_accpt_str, sizeof(ws_key_accpt_str) - 1);
    tmp = fiobj_str_buf(32);
    stmp = fiobj_obj2cstr(tmp);
    fiobj_str_resize(tmp,
                     fio_base64_encode(stmp.data, fio_sha1_result(&sha1), 20));
    http_set_header(h, HTTP_HEADER_CONNECTION, fiobj_dup(HTTP_HVALUE_WS_UPGRADE));
    http_set_header(h, HTTP_HEADER_UPGRADE, fiobj_dup(HTTP_HVALUE_WEBSOCKET));
    http_set_header(h, HTTP_HEADER_WS_SEC_KEY, tmp);
    h->status = 101;
    http1pr_s *pr = handle2pr(h);
    const intptr_t uuid = handle2pr(h)->p.uuid;
    http_settings_s *set = handle2pr(h)->p.settings;
    http_finish(h);
    pr->stop = 1;
    websocket_attach(uuid, set, args, pr->parser.state.next,
                     pr->buf_len - (intptr_t)(pr->parser.state.next - pr->buf));
    return 0;
  bad_request:
    http_send_error(h, 400);
    if (args->on_close)
      args->on_close(0, args->udata);
    return -1;
  }
  
  static int http1_http2websocket_client(http_s *h, websocket_settings_s *args) {
    http1pr_s *p = handle2pr(h);
    /* We're done with the HTTP stage, so we call the `on_finish` */
    if (p->p.settings->on_finish)
      p->p.settings->on_finish(p->p.settings);
    /* Copy the Websocket setting arguments to the HTTP settings `udata` */
    p->p.settings->udata = fio_malloc(sizeof(*args));
    ((websocket_settings_s *)(p->p.settings->udata))[0] = *args;
    /* Set callbacks */
    p->p.settings->on_finish = http1_websocket_client_on_hangup;   /* unknown */
    p->p.settings->on_upgrade = http1_websocket_client_on_upgrade; /* sucess */
    p->p.settings->on_response = http1_websocket_client_on_failed; /* failed */
    p->p.settings->on_request = http1_websocket_client_on_failed;  /* failed */
    /* Set headers */
    http_set_header(h, HTTP_HEADER_CONNECTION, fiobj_dup(HTTP_HVALUE_WS_UPGRADE));
    http_set_header(h, HTTP_HEADER_UPGRADE, fiobj_dup(HTTP_HVALUE_WEBSOCKET));
    http_set_header(h, HTTP_HVALUE_WS_SEC_VERSION,
                    fiobj_dup(HTTP_HVALUE_WS_VERSION));
  
    /* we don't set the Origin header since we're not a browser... should we? */
    // http_set_header(
    //     h, HTTP_HEADER_ORIGIN,
    //     fiobj_dup(fiobj_hash_get2(h->private_data.out_headers,
    //                               fiobj_obj2hash(HTTP_HEADER_HOST))));
  
    /* create nonce */
    uint64_t key[2]; /* 16 bytes */
    key[0] = (uintptr_t)h ^ (uint64_t)fio_last_tick().tv_sec;
    key[1] = (uintptr_t)args->udata ^ (uint64_t)fio_last_tick().tv_nsec;
    FIOBJ encoded = fiobj_str_buf(26); /* we need 24 really. */
    fio_str_info_s tmp = fiobj_obj2cstr(encoded);
    tmp.len = fio_base64_encode(tmp.data, (char *)key, 16);
    fiobj_str_resize(encoded, tmp.len);
    http_set_header(h, HTTP_HEADER_WS_SEC_CLIENT_KEY, encoded);
    http_finish(h);
    return 0;
  }
  
  static int http1_http2websocket(http_s *h, websocket_settings_s *args) {
    assert(h);
    http1pr_s *p = handle2pr(h);
  
    if (p->is_client == 0) {
      return http1_http2websocket_server(h, args);
    }
    return http1_http2websocket_client(h, args);
  }
  
  /* *****************************************************************************
  EventSource Support (SSE)
  ***************************************************************************** */
  
  #undef http_upgrade2sse
  
  typedef struct {
    fio_protocol_s p;
    http_sse_internal_s *sse;
  } http1_sse_fio_protocol_s;
  
  static void http1_sse_on_ready(intptr_t uuid, fio_protocol_s *p_) {
    http1_sse_fio_protocol_s *p = (http1_sse_fio_protocol_s *)p_;
    if (p->sse->sse.on_ready)
      p->sse->sse.on_ready(&p->sse->sse);
    (void)uuid;
  }
  static uint8_t http1_sse_on_shutdown(intptr_t uuid, fio_protocol_s *p_) {
    http1_sse_fio_protocol_s *p = (http1_sse_fio_protocol_s *)p_;
    if (p->sse->sse.on_shutdown)
      p->sse->sse.on_shutdown(&p->sse->sse);
    return 0;
    (void)uuid;
  }
  static void http1_sse_on_close(intptr_t uuid, fio_protocol_s *p_) {
    http1_sse_fio_protocol_s *p = (http1_sse_fio_protocol_s *)p_;
    http_sse_destroy(p->sse);
    fio_free(p);
    (void)uuid;
  }
  static void http1_sse_ping(intptr_t uuid, fio_protocol_s *p_) {
    fio_write2(uuid, .data.buffer = ": ping\n\n", .length = 8,
               .after.dealloc = FIO_DEALLOC_NOOP);
    (void)p_;
  }
  
  /**
   * Upgrades an HTTP connection to an EventSource (SSE) connection.
   *
   * Thie `http_s` handle will be invalid after this call.
   *
   * On HTTP/1.1 connections, this will preclude future requests using the same
   * connection.
   */
  static int http1_upgrade2sse(http_s *h, http_sse_s *sse) {
    const intptr_t uuid = handle2pr(h)->p.uuid;
    /* send response */
    h->status = 200;
    http_set_header(h, HTTP_HEADER_CONTENT_TYPE, fiobj_dup(HTTP_HVALUE_SSE_MIME));
    http_set_header(h, HTTP_HEADER_CACHE_CONTROL,
                    fiobj_dup(HTTP_HVALUE_NO_CACHE));
    http_set_header(h, HTTP_HEADER_CONTENT_ENCODING,
                    fiobj_str_new("identity", 8));
    handle2pr(h)->stop = 1;
    htt1p_finish(h); /* avoid the enforced content length in http_finish */
  
    /* switch protocol to SSE */
    http1_sse_fio_protocol_s *sse_pr = fio_malloc(sizeof(*sse_pr));
    if (!sse_pr)
      goto failed;
    *sse_pr = (http1_sse_fio_protocol_s){
        .p =
            {
                .on_ready = http1_sse_on_ready,
                .on_shutdown = http1_sse_on_shutdown,
                .on_close = http1_sse_on_close,
                .ping = http1_sse_ping,
            },
        .sse = fio_malloc(sizeof(*(sse_pr->sse))),
    };
  
    if (!sse_pr->sse)
      goto failed;
  
    http_sse_init(sse_pr->sse, uuid, &HTTP1_VTABLE, sse);
    fio_timeout_set(uuid, handle2pr(h)->p.settings->ws_timeout);
    if (sse->on_open)
      sse->on_open(&sse_pr->sse->sse);
    fio_attach(uuid, &sse_pr->p);
    return 0;
  
  failed:
    fio_close(handle2pr(h)->p.uuid);
    if (sse->on_close)
      sse->on_close(sse);
    return -1;
    (void)sse;
  }
  
  #undef http_sse_write
  /**
   * Writes data to an EventSource (SSE) connection.
   *
   * See the {struct http_sse_write_args} for possible named arguments.
   */
  static int http1_sse_write(http_sse_s *sse, FIOBJ str) {
    return fiobj_send_free(((http_sse_internal_s *)sse)->uuid, str);
  }
  
  /**
   * Closes an EventSource (SSE) connection.
   */
  static int http1_sse_close(http_sse_s *sse) {
    fio_close(((http_sse_internal_s *)sse)->uuid);
    return 0;
  }
  /* *****************************************************************************
  Virtual Table Decleration
  ***************************************************************************** */
  
  struct http_vtable_s HTTP1_VTABLE = {
      .http_send_body = http1_send_body,
      .http_sendfile = http1_sendfile,
      .http_finish = htt1p_finish,
      .http_push_data = http1_push_data,
      .http_push_file = http1_push_file,
      .http_on_pause = http1_on_pause,
      .http_on_resume = http1_on_resume,
      .http_hijack = http1_hijack,
      .http2websocket = http1_http2websocket,
      .http_upgrade2sse = http1_upgrade2sse,
      .http_sse_write = http1_sse_write,
      .http_sse_close = http1_sse_close,
  };
  
  void *http1_vtable(void) { return (void *)&HTTP1_VTABLE; }
  
  /* *****************************************************************************
  Parser Callbacks
  ***************************************************************************** */
  
  /** called when a request was received. */
  static int http1_on_request(http1_parser_s *parser) {
    http1pr_s *p = parser2http(parser);
    http_on_request_handler______internal(&http1_pr2handle(p), p->p.settings);
    if (p->request.method && !p->stop)
      http_finish(&p->request);
    h1_reset(p);
    return fio_is_closed(p->p.uuid);
  }
  /** called when a response was received. */
  static int http1_on_response(http1_parser_s *parser) {
    http1pr_s *p = parser2http(parser);
    http_on_response_handler______internal(&http1_pr2handle(p), p->p.settings);
    if (p->request.status_str && !p->stop)
      http_finish(&p->request);
    h1_reset(p);
    return fio_is_closed(p->p.uuid);
  }
  /** called when a request method is parsed. */
  static int http1_on_method(http1_parser_s *parser, char *method,
                             size_t method_len) {
    http1_pr2handle(parser2http(parser)).method =
        fiobj_str_new(method, method_len);
    parser2http(parser)->header_size += method_len;
    return 0;
  }
  
  /** called when a response status is parsed. the status_str is the string
   * without the prefixed numerical status indicator.*/
  static int http1_on_status(http1_parser_s *parser, size_t status,
                             char *status_str, size_t len) {
    http1_pr2handle(parser2http(parser)).status_str =
        fiobj_str_new(status_str, len);
    http1_pr2handle(parser2http(parser)).status = status;
    parser2http(parser)->header_size += len;
    return 0;
  }
  
  /** called when a request path (excluding query) is parsed. */
  static int http1_on_path(http1_parser_s *parser, char *path, size_t len) {
    http1_pr2handle(parser2http(parser)).path = fiobj_str_new(path, len);
    parser2http(parser)->header_size += len;
    return 0;
  }
  
  /** called when a request path (excluding query) is parsed. */
  static int http1_on_query(http1_parser_s *parser, char *query, size_t len) {
    http1_pr2handle(parser2http(parser)).query = fiobj_str_new(query, len);
    parser2http(parser)->header_size += len;
    return 0;
  }
  /** called when a the HTTP/1.x version is parsed. */
  static int http1_on_http_version(http1_parser_s *parser, char *version,
                                   size_t len) {
    http1_pr2handle(parser2http(parser)).version = fiobj_str_new(version, len);
    parser2http(parser)->header_size += len;
  /* start counting - occurs on the first line of both requests and responses */
  #if FIO_HTTP_EXACT_LOGGING
    clock_gettime(CLOCK_REALTIME,
                  &http1_pr2handle(parser2http(parser)).received_at);
  #else
    http1_pr2handle(parser2http(parser)).received_at = fio_last_tick();
  #endif
    return 0;
  }
  /** called when a header is parsed. */
  static int http1_on_header(http1_parser_s *parser, char *name, size_t name_len,
                             char *data, size_t data_len) {
    FIOBJ sym;
    FIOBJ obj;
    if (!http1_pr2handle(parser2http(parser)).headers) {
      FIO_LOG_ERROR("(http1 parse ordering error) missing HashMap for header "
                    "%s: %s",
                    name, data);
      http_send_error2(500, parser2http(parser)->p.uuid,
                       parser2http(parser)->p.settings);
      return -1;
    }
    parser2http(parser)->header_size += name_len + data_len;
    if (parser2http(parser)->header_size >=
            parser2http(parser)->max_header_size ||
        fiobj_hash_count(http1_pr2handle(parser2http(parser)).headers) >
            HTTP_MAX_HEADER_COUNT) {
      if (parser2http(parser)->p.settings->log) {
        FIO_LOG_WARNING("(HTTP) security alert - header flood detected.");
      }
      http_send_error(&http1_pr2handle(parser2http(parser)), 413);
      return -1;
    }
    sym = fiobj_str_new(name, name_len);
    obj = fiobj_str_new(data, data_len);
    set_header_add(http1_pr2handle(parser2http(parser)).headers, sym, obj);
    fiobj_free(sym);
    return 0;
  }
  /** called when a body chunk is parsed. */
  static int http1_on_body_chunk(http1_parser_s *parser, char *data,
                                 size_t data_len) {
    if (parser->state.content_length >
            (ssize_t)parser2http(parser)->p.settings->max_body_size ||
        parser->state.read >
            (ssize_t)parser2http(parser)->p.settings->max_body_size) {
      http_send_error(&http1_pr2handle(parser2http(parser)), 413);
      return -1; /* test every time, in case of chunked data */
    }
    if (!parser->state.read) {
      if (parser->state.content_length > 0 &&
          parser->state.content_length <= HTTP_MAX_HEADER_LENGTH) {
        http1_pr2handle(parser2http(parser)).body = fiobj_data_newstr();
      } else {
        http1_pr2handle(parser2http(parser)).body = fiobj_data_newtmpfile();
      }
    }
    fiobj_data_write(http1_pr2handle(parser2http(parser)).body, data, data_len);
    return 0;
  }
  
  /** called when a protocol error occurred. */
  static int http1_on_error(http1_parser_s *parser) {
    FIO_LOG_DEBUG("HTTP parser error.");
    fio_close(parser2http(parser)->p.uuid);
    return -1;
  }
  
  /* *****************************************************************************
  Connection Callbacks
  ***************************************************************************** */
  
  static inline void http1_consume_data(intptr_t uuid, http1pr_s *p) {
    if (fio_pending(uuid) > 4) {
      goto throttle;
    }
    ssize_t i = 0;
    size_t org_len = p->buf_len;
    int pipeline_limit = 8;
    if (!p->buf_len)
      return;
    do {
      i = http1_fio_parser(.parser = &p->parser,
                           .buffer = p->buf + (org_len - p->buf_len),
                           .length = p->buf_len, .on_request = http1_on_request,
                           .on_response = http1_on_response,
                           .on_method = http1_on_method,
                           .on_status = http1_on_status, .on_path = http1_on_path,
                           .on_query = http1_on_query,
                           .on_http_version = http1_on_http_version,
                           .on_header = http1_on_header,
                           .on_body_chunk = http1_on_body_chunk,
                           .on_error = http1_on_error);
      p->buf_len -= i;
      --pipeline_limit;
    } while (i && p->buf_len && pipeline_limit && !p->stop);
  
    if (p->buf_len && org_len != p->buf_len) {
      memmove(p->buf, p->buf + (org_len - p->buf_len), p->buf_len);
    }
  
    if (p->buf_len == HTTP_MAX_HEADER_LENGTH) {
      /* no room to read... parser not consuming data */
      if (p->request.method)
        http_send_error(&p->request, 413);
      else {
        p->request.method = fiobj_str_tmp();
        http_send_error(&p->request, 413);
      }
    }
  
    if (!pipeline_limit) {
      fio_force_event(uuid, FIO_EVENT_ON_DATA);
    }
    return;
  
  throttle:
    /* throttle busy clients (slowloris) */
    fio_suspend(uuid);
    FIO_LOG_DEBUG("(HTTP/1,1) throttling client at %.*s",
                  (int)fio_peer_addr(uuid).len, fio_peer_addr(uuid).data);
  }
  
  /** called when a data is available, but will not run concurrently */
  static void http1_on_data(intptr_t uuid, fio_protocol_s *protocol) {
    http1pr_s *p = (http1pr_s *)protocol;
    if (p->stop) {
      fio_suspend(uuid);
      return;
    }
    ssize_t i = 0;
    if (HTTP_MAX_HEADER_LENGTH - p->buf_len)
      i = fio_read(uuid, p->buf + p->buf_len,
                   HTTP_MAX_HEADER_LENGTH - p->buf_len);
    if (i > 0) {
      p->buf_len += i;
    }
    http1_consume_data(uuid, p);
  }
  
  /** called when the connection was closed, but will not run concurrently */
  static void http1_on_close(intptr_t uuid, fio_protocol_s *protocol) {
    http1_destroy(protocol);
    (void)uuid;
  }
  
  /** called when the connection was closed, but will not run concurrently */
  static void http1_on_ready(intptr_t uuid, fio_protocol_s *protocol) {
    /* resume slow clients from suspension */
    fio_force_event(uuid, FIO_EVENT_ON_DATA);
    (void)protocol;
  }
  
  /** called when a data is available for the first time */
  static void http1_on_data_first_time(intptr_t uuid, fio_protocol_s *protocol) {
    http1pr_s *p = (http1pr_s *)protocol;
    ssize_t i;
  
    i = fio_read(uuid, p->buf + p->buf_len, HTTP_MAX_HEADER_LENGTH - p->buf_len);
  
    if (i <= 0)
      return;
    p->buf_len += i;
  
    /* ensure future reads skip this first time HTTP/2.0 test */
    p->p.protocol.on_data = http1_on_data;
    if (i >= 24 && !memcmp(p->buf, "PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n", 24)) {
      FIO_LOG_WARNING("client claimed unsupported HTTP/2 prior knowledge.");
      fio_close(uuid);
      return;
    }
  
    /* Finish handling the same way as the normal `on_data` */
    http1_consume_data(uuid, p);
  }
  
  /* *****************************************************************************
  Public API
  ***************************************************************************** */
  
  /** Creates an HTTP1 protocol object and handles any unread data in the buffer
   * (if any). */
  fio_protocol_s *http1_new(uintptr_t uuid, http_settings_s *settings,
                            void *unread_data, size_t unread_length) {
    if (unread_data && unread_length > HTTP_MAX_HEADER_LENGTH)
      return NULL;
    http1pr_s *p = fio_malloc(sizeof(*p) + HTTP_MAX_HEADER_LENGTH);
    // FIO_LOG_DEBUG("Allocated HTTP/1.1 protocol at. %p", (void *)p);
    FIO_ASSERT_ALLOC(p);
    *p = (http1pr_s){
        .p.protocol =
            {
                .on_data = http1_on_data_first_time,
                .on_close = http1_on_close,
                .on_ready = http1_on_ready,
            },
        .p.uuid = uuid,
        .p.settings = settings,
        .max_header_size = settings->max_header_size,
        .is_client = settings->is_client,
    };
    http_s_new(&p->request, &p->p, &HTTP1_VTABLE);
    if (unread_data && unread_length <= HTTP_MAX_HEADER_LENGTH) {
      memcpy(p->buf, unread_data, unread_length);
      p->buf_len = unread_length;
    }
    fio_attach(uuid, &p->p.protocol);
    if (unread_data && unread_length <= HTTP_MAX_HEADER_LENGTH) {
      fio_force_event(uuid, FIO_EVENT_ON_DATA);
    }
    return &p->p.protocol;
  }
  
  /** Manually destroys the HTTP1 protocol object. */
  void http1_destroy(fio_protocol_s *pr) {
    http1pr_s *p = (http1pr_s *)pr;
    http1_pr2handle(p).status = 0;
    http_s_destroy(&http1_pr2handle(p), 0);
    fio_free(p);
    // FIO_LOG_DEBUG("Deallocated HTTP/1.1 protocol at. %p", (void *)p);
  }
  
  /* *****************************************************************************
  Protocol Data
  ***************************************************************************** */
  
  // clang-format off
  #define HTTP_SET_STATUS_STR(status, str) [((status)-100)] = { .data = (char*)("HTTP/1.1 " #status " " str "\r\n"), .len = (sizeof("HTTP/1.1 " #status " " str "\r\n") - 1) }
  // #undef HTTP_SET_STATUS_STR
  // clang-format on
  
  static fio_str_info_s http1pr_status2str(uintptr_t status) {
    static fio_str_info_s status2str[] = {
        HTTP_SET_STATUS_STR(100, "Continue"),
        HTTP_SET_STATUS_STR(101, "Switching Protocols"),
        HTTP_SET_STATUS_STR(102, "Processing"),
        HTTP_SET_STATUS_STR(103, "Early Hints"),
        HTTP_SET_STATUS_STR(200, "OK"),
        HTTP_SET_STATUS_STR(201, "Created"),
        HTTP_SET_STATUS_STR(202, "Accepted"),
        HTTP_SET_STATUS_STR(203, "Non-Authoritative Information"),
        HTTP_SET_STATUS_STR(204, "No Content"),
        HTTP_SET_STATUS_STR(205, "Reset Content"),
        HTTP_SET_STATUS_STR(206, "Partial Content"),
        HTTP_SET_STATUS_STR(207, "Multi-Status"),
        HTTP_SET_STATUS_STR(208, "Already Reported"),
        HTTP_SET_STATUS_STR(226, "IM Used"),
        HTTP_SET_STATUS_STR(300, "Multiple Choices"),
        HTTP_SET_STATUS_STR(301, "Moved Permanently"),
        HTTP_SET_STATUS_STR(302, "Found"),
        HTTP_SET_STATUS_STR(303, "See Other"),
        HTTP_SET_STATUS_STR(304, "Not Modified"),
        HTTP_SET_STATUS_STR(305, "Use Proxy"),
        HTTP_SET_STATUS_STR(306, "(Unused), "),
        HTTP_SET_STATUS_STR(307, "Temporary Redirect"),
        HTTP_SET_STATUS_STR(308, "Permanent Redirect"),
        HTTP_SET_STATUS_STR(400, "Bad Request"),
        HTTP_SET_STATUS_STR(403, "Forbidden"),
        HTTP_SET_STATUS_STR(404, "Not Found"),
        HTTP_SET_STATUS_STR(401, "Unauthorized"),
        HTTP_SET_STATUS_STR(402, "Payment Required"),
        HTTP_SET_STATUS_STR(405, "Method Not Allowed"),
        HTTP_SET_STATUS_STR(406, "Not Acceptable"),
        HTTP_SET_STATUS_STR(407, "Proxy Authentication Required"),
        HTTP_SET_STATUS_STR(408, "Request Timeout"),
        HTTP_SET_STATUS_STR(409, "Conflict"),
        HTTP_SET_STATUS_STR(410, "Gone"),
        HTTP_SET_STATUS_STR(411, "Length Required"),
        HTTP_SET_STATUS_STR(412, "Precondition Failed"),
        HTTP_SET_STATUS_STR(413, "Payload Too Large"),
        HTTP_SET_STATUS_STR(414, "URI Too Long"),
        HTTP_SET_STATUS_STR(415, "Unsupported Media Type"),
        HTTP_SET_STATUS_STR(416, "Range Not Satisfiable"),
        HTTP_SET_STATUS_STR(417, "Expectation Failed"),
        HTTP_SET_STATUS_STR(421, "Misdirected Request"),
        HTTP_SET_STATUS_STR(422, "Unprocessable Entity"),
        HTTP_SET_STATUS_STR(423, "Locked"),
        HTTP_SET_STATUS_STR(424, "Failed Dependency"),
        HTTP_SET_STATUS_STR(425, "Unassigned"),
        HTTP_SET_STATUS_STR(426, "Upgrade Required"),
        HTTP_SET_STATUS_STR(427, "Unassigned"),
        HTTP_SET_STATUS_STR(428, "Precondition Required"),
        HTTP_SET_STATUS_STR(429, "Too Many Requests"),
        HTTP_SET_STATUS_STR(430, "Unassigned"),
        HTTP_SET_STATUS_STR(431, "Request Header Fields Too Large"),
        HTTP_SET_STATUS_STR(500, "Internal Server Error"),
        HTTP_SET_STATUS_STR(501, "Not Implemented"),
        HTTP_SET_STATUS_STR(502, "Bad Gateway"),
        HTTP_SET_STATUS_STR(503, "Service Unavailable"),
        HTTP_SET_STATUS_STR(504, "Gateway Timeout"),
        HTTP_SET_STATUS_STR(505, "HTTP Version Not Supported"),
        HTTP_SET_STATUS_STR(506, "Variant Also Negotiates"),
        HTTP_SET_STATUS_STR(507, "Insufficient Storage"),
        HTTP_SET_STATUS_STR(508, "Loop Detected"),
        HTTP_SET_STATUS_STR(509, "Unassigned"),
        HTTP_SET_STATUS_STR(510, "Not Extended"),
        HTTP_SET_STATUS_STR(511, "Network Authentication Required"),
    };
    fio_str_info_s ret = (fio_str_info_s){.len = 0, .data = NULL};
    if (status >= 100 &&
        (status - 100) < sizeof(status2str) / sizeof(status2str[0]))
      ret = status2str[status - 100];
    if (!ret.data) {
      ret = status2str[400];
    }
    return ret;
  }
  #undef HTTP_SET_STATUS_STR
  