| /* | |
| * Copyright (C) Igor Sysoev | |
| * Copyright (C) Nginx, Inc. | |
| */ | |
| #include <ngx_config.h> | |
| #include <ngx_core.h> | |
| #include <ngx_event.h> | |
| /* | |
| * Although FreeBSD sendfile() allows to pass a header and a trailer, | |
| * it cannot send a header with a part of the file in one packet until | |
| * FreeBSD 5.3. Besides, over the fast ethernet connection sendfile() | |
| * may send the partially filled packets, i.e. the 8 file pages may be sent | |
| * as the 11 full 1460-bytes packets, then one incomplete 324-bytes packet, | |
| * and then again the 11 full 1460-bytes packets. | |
| * | |
| * Therefore we use the TCP_NOPUSH option (similar to Linux's TCP_CORK) | |
| * to postpone the sending - it not only sends a header and the first part of | |
| * the file in one packet, but also sends the file pages in the full packets. | |
| * | |
| * But until FreeBSD 4.5 turning TCP_NOPUSH off does not flush a pending | |
| * data that less than MSS, so that data may be sent with 5 second delay. | |
| * So we do not use TCP_NOPUSH on FreeBSD prior to 4.5, although it can be used | |
| * for non-keepalive HTTP connections. | |
| */ | |
| ngx_chain_t * | |
| ngx_freebsd_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit) | |
| { | |
| int rc, flags; | |
| off_t send, prev_send, sent; | |
| size_t file_size; | |
| ssize_t n; | |
| ngx_uint_t eintr, eagain; | |
| ngx_err_t err; | |
| ngx_buf_t *file; | |
| ngx_event_t *wev; | |
| ngx_chain_t *cl; | |
| ngx_iovec_t header, trailer; | |
| struct sf_hdtr hdtr; | |
| struct iovec headers[NGX_IOVS_PREALLOCATE]; | |
| struct iovec trailers[NGX_IOVS_PREALLOCATE]; | |
| #if (NGX_HAVE_AIO_SENDFILE) | |
| ngx_uint_t ebusy; | |
| ngx_event_aio_t *aio; | |
| #endif | |
| wev = c->write; | |
| if (!wev->ready) { | |
| return in; | |
| } | |
| #if (NGX_HAVE_KQUEUE) | |
| if ((ngx_event_flags & NGX_USE_KQUEUE_EVENT) && wev->pending_eof) { | |
| (void) ngx_connection_error(c, wev->kq_errno, | |
| "kevent() reported about an closed connection"); | |
| wev->error = 1; | |
| return NGX_CHAIN_ERROR; | |
| } | |
| #endif | |
| /* the maximum limit size is the maximum size_t value - the page size */ | |
| if (limit == 0 || limit > (off_t) (NGX_MAX_SIZE_T_VALUE - ngx_pagesize)) { | |
| limit = NGX_MAX_SIZE_T_VALUE - ngx_pagesize; | |
| } | |
| send = 0; | |
| eagain = 0; | |
| flags = 0; | |
| #if (NGX_HAVE_AIO_SENDFILE && NGX_SUPPRESS_WARN) | |
| aio = NULL; | |
| file = NULL; | |
| #endif | |
| header.iovs = headers; | |
| header.nalloc = NGX_IOVS_PREALLOCATE; | |
| trailer.iovs = trailers; | |
| trailer.nalloc = NGX_IOVS_PREALLOCATE; | |
| for ( ;; ) { | |
| eintr = 0; | |
| #if (NGX_HAVE_AIO_SENDFILE) | |
| ebusy = 0; | |
| #endif | |
| prev_send = send; | |
| /* create the header iovec and coalesce the neighbouring bufs */ | |
| cl = ngx_output_chain_to_iovec(&header, in, limit - send, c->log); | |
| if (cl == NGX_CHAIN_ERROR) { | |
| return NGX_CHAIN_ERROR; | |
| } | |
| send += header.size; | |
| if (cl && cl->buf->in_file && send < limit) { | |
| file = cl->buf; | |
| /* coalesce the neighbouring file bufs */ | |
| file_size = (size_t) ngx_chain_coalesce_file(&cl, limit - send); | |
| send += file_size; | |
| if (send < limit) { | |
| /* | |
| * create the trailer iovec and coalesce the neighbouring bufs | |
| */ | |
| cl = ngx_output_chain_to_iovec(&trailer, cl, limit - send, | |
| c->log); | |
| if (cl == NGX_CHAIN_ERROR) { | |
| return NGX_CHAIN_ERROR; | |
| } | |
| send += trailer.size; | |
| } else { | |
| trailer.count = 0; | |
| } | |
| if (ngx_freebsd_use_tcp_nopush | |
| && c->tcp_nopush == NGX_TCP_NOPUSH_UNSET) | |
| { | |
| if (ngx_tcp_nopush(c->fd) == NGX_ERROR) { | |
| err = ngx_socket_errno; | |
| /* | |
| * there is a tiny chance to be interrupted, however, | |
| * we continue a processing without the TCP_NOPUSH | |
| */ | |
| if (err != NGX_EINTR) { | |
| wev->error = 1; | |
| (void) ngx_connection_error(c, err, | |
| ngx_tcp_nopush_n " failed"); | |
| return NGX_CHAIN_ERROR; | |
| } | |
| } else { | |
| c->tcp_nopush = NGX_TCP_NOPUSH_SET; | |
| ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, 0, | |
| "tcp_nopush"); | |
| } | |
| } | |
| /* | |
| * sendfile() does unneeded work if sf_hdtr's count is 0, | |
| * but corresponding pointer is not NULL | |
| */ | |
| hdtr.headers = header.count ? header.iovs : NULL; | |
| hdtr.hdr_cnt = header.count; | |
| hdtr.trailers = trailer.count ? trailer.iovs : NULL; | |
| hdtr.trl_cnt = trailer.count; | |
| /* | |
| * the "nbytes bug" of the old sendfile() syscall: | |
| * http://bugs.freebsd.org/33771 | |
| */ | |
| if (!ngx_freebsd_sendfile_nbytes_bug) { | |
| header.size = 0; | |
| } | |
| sent = 0; | |
| #if (NGX_HAVE_AIO_SENDFILE) | |
| aio = file->file->aio; | |
| flags = (aio && aio->preload_handler) ? SF_NODISKIO : 0; | |
| #endif | |
| rc = sendfile(file->file->fd, c->fd, file->file_pos, | |
| file_size + header.size, &hdtr, &sent, flags); | |
| if (rc == -1) { | |
| err = ngx_errno; | |
| switch (err) { | |
| case NGX_EAGAIN: | |
| eagain = 1; | |
| break; | |
| case NGX_EINTR: | |
| eintr = 1; | |
| break; | |
| #if (NGX_HAVE_AIO_SENDFILE) | |
| case NGX_EBUSY: | |
| ebusy = 1; | |
| break; | |
| #endif | |
| default: | |
| wev->error = 1; | |
| (void) ngx_connection_error(c, err, "sendfile() failed"); | |
| return NGX_CHAIN_ERROR; | |
| } | |
| ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, err, | |
| "sendfile() sent only %O bytes", sent); | |
| /* | |
| * sendfile() in FreeBSD 3.x-4.x may return value >= 0 | |
| * on success, although only 0 is documented | |
| */ | |
| } else if (rc >= 0 && sent == 0) { | |
| /* | |
| * if rc is OK and sent equal to zero, then someone | |
| * has truncated the file, so the offset became beyond | |
| * the end of the file | |
| */ | |
| ngx_log_error(NGX_LOG_ALERT, c->log, 0, | |
| "sendfile() reported that \"%s\" was truncated at %O", | |
| file->file->name.data, file->file_pos); | |
| return NGX_CHAIN_ERROR; | |
| } | |
| ngx_log_debug4(NGX_LOG_DEBUG_EVENT, c->log, 0, | |
| "sendfile: %d, @%O %O:%uz", | |
| rc, file->file_pos, sent, file_size + header.size); | |
| } else { | |
| n = ngx_writev(c, &header); | |
| if (n == NGX_ERROR) { | |
| return NGX_CHAIN_ERROR; | |
| } | |
| sent = (n == NGX_AGAIN) ? 0 : n; | |
| } | |
| c->sent += sent; | |
| in = ngx_chain_update_sent(in, sent); | |
| #if (NGX_HAVE_AIO_SENDFILE) | |
| if (ebusy) { | |
| if (aio->event.active) { | |
| /* | |
| * tolerate duplicate calls; they can happen due to subrequests | |
| * or multiple calls of the next body filter from a filter | |
| */ | |
| if (sent) { | |
| c->busy_count = 0; | |
| } | |
| return in; | |
| } | |
| if (sent == 0) { | |
| c->busy_count++; | |
| if (c->busy_count > 2) { | |
| ngx_log_error(NGX_LOG_ALERT, c->log, 0, | |
| "sendfile(%V) returned busy again", | |
| &file->file->name); | |
| c->busy_count = 0; | |
| aio->preload_handler = NULL; | |
| send = prev_send; | |
| continue; | |
| } | |
| } else { | |
| c->busy_count = 0; | |
| } | |
| n = aio->preload_handler(file); | |
| if (n > 0) { | |
| send = prev_send + sent; | |
| continue; | |
| } | |
| return in; | |
| } | |
| if (flags == SF_NODISKIO) { | |
| c->busy_count = 0; | |
| } | |
| #endif | |
| if (eagain) { | |
| /* | |
| * sendfile() may return EAGAIN, even if it has sent a whole file | |
| * part, it indicates that the successive sendfile() call would | |
| * return EAGAIN right away and would not send anything. | |
| * We use it as a hint. | |
| */ | |
| wev->ready = 0; | |
| return in; | |
| } | |
| if (eintr) { | |
| send = prev_send + sent; | |
| continue; | |
| } | |
| if (send - prev_send != sent) { | |
| wev->ready = 0; | |
| return in; | |
| } | |
| if (send >= limit || in == NULL) { | |
| return in; | |
| } | |
| } | |
| } |