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]; 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; header.iovs = headers; header.nalloc = NGX_IOVS_PREALLOCATE; trailer.iovs = trailers; trailer.nalloc = NGX_IOVS_PREALLOCATE; for ( ;; ) { eintr = 0; 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; /* 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; 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) flags = c->aio_sendfile ? 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: c->busy_sendfile = file; 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 (c->busy_sendfile) { return in; } #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; } } }
ngx_chain_t * ngx_darwin_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit) { int rc; off_t send, prev_send, sent; off_t file_size; ssize_t n; ngx_uint_t eintr; 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]; 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; header.iovs = headers; header.nalloc = NGX_IOVS_PREALLOCATE; trailer.iovs = trailers; trailer.nalloc = NGX_IOVS_PREALLOCATE; for ( ;; ) { eintr = 0; 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 = ngx_chain_coalesce_file(&cl, limit - send); send += file_size; if (header.count == 0) { /* * 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; } /* * sendfile() returns EINVAL 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; sent = header.size + file_size; ngx_log_debug3(NGX_LOG_DEBUG_EVENT, c->log, 0, "sendfile: @%O %O h:%uz", file->file_pos, sent, header.size); /* 这里开始真正的发送文件, * 当输入localhost的时候默认的是index.html * 那么此时这里的file->file->name就是xxxx/html/index.html , * 发送过去之后,客户端页面就可以正常显示了。 */ rc = sendfile(file->file->fd, c->fd, file->file_pos, &sent, &hdtr, 0); if (rc == -1) { err = ngx_errno; switch (err) { case NGX_EAGAIN: break; case NGX_EINTR: eintr = 1; break; 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); } if (rc == 0 && sent == 0) { /* * if rc 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", file->file->name.data); return NGX_CHAIN_ERROR; } ngx_log_debug4(NGX_LOG_DEBUG_EVENT, c->log, 0, "sendfile: %d, @%O %O:%O", 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 (eintr) { send = prev_send + sent; continue; } if (send - prev_send != sent) { wev->ready = 0; return in; } if (send >= limit || in == NULL) { return in; } } }
//遍历r->out上的每一个缓存块,根据缓存块里的数据类型调用不同的系统接口函数将数据写出到客户端。 ngx_chain_t * ngx_linux_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit) { int tcp_nodelay; off_t send, prev_send; size_t file_size, sent; ssize_t n; ngx_err_t err; ngx_buf_t *file; ngx_event_t *wev; ngx_chain_t *cl; ngx_iovec_t header; struct iovec headers[NGX_IOVS_PREALLOCATE]; #if (NGX_THREADS) ngx_int_t rc; ngx_uint_t thread_handled, thread_complete; #endif wev = c->write; if (!wev->ready) { return in; } /* the maximum limit size is 2G-1 - the page size */ if (limit == 0 || limit > (off_t) (NGX_SENDFILE_MAXSIZE - ngx_pagesize)) { limit = NGX_SENDFILE_MAXSIZE - ngx_pagesize; } send = 0; header.iovs = headers; header.nalloc = NGX_IOVS_PREALLOCATE; for ( ;; ) { prev_send = send; #if (NGX_THREADS) thread_handled = 0; thread_complete = 0; #endif /* create the 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; /* set TCP_CORK if there is a header before a file */ if (c->tcp_nopush == NGX_TCP_NOPUSH_UNSET && header.count != 0 && cl && cl->buf->in_file) { /* the TCP_CORK and TCP_NODELAY are mutually exclusive */ if (c->tcp_nodelay == NGX_TCP_NODELAY_SET) { tcp_nodelay = 0; if (setsockopt(c->fd, IPPROTO_TCP, TCP_NODELAY, (const void *) &tcp_nodelay, sizeof(int)) == -1) { err = ngx_socket_errno; /* * there is a tiny chance to be interrupted, however, * we continue a processing with the TCP_NODELAY * and without the TCP_CORK */ if (err != NGX_EINTR) { wev->error = 1; ngx_connection_error(c, err, "setsockopt(TCP_NODELAY) failed"); return NGX_CHAIN_ERROR; } } else { c->tcp_nodelay = NGX_TCP_NODELAY_UNSET; ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, 0, "no tcp_nodelay"); } } if (c->tcp_nodelay == NGX_TCP_NODELAY_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_CORK */ if (err != NGX_EINTR) { wev->error = 1; 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"); } } } /* get the file buf */ if (header.count == 0 && 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 1 if (file_size == 0) { ngx_debug_point(); return NGX_CHAIN_ERROR; } #endif #if (NGX_THREADS) if (file->file->thread_handler) { rc = ngx_linux_sendfile_thread(c, file, file_size, &sent); switch (rc) { case NGX_OK: thread_handled = 1; break; case NGX_DONE: thread_complete = 1; break; case NGX_AGAIN: break; default: /* NGX_ERROR */ return NGX_CHAIN_ERROR; } } else #endif { n = ngx_linux_sendfile(c, file, file_size); if (n == NGX_ERROR) { return NGX_CHAIN_ERROR; } sent = (n == NGX_AGAIN) ? 0 : n; } } 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 ((size_t) (send - prev_send) != sent) { #if (NGX_THREADS) if (thread_handled) { return in; } if (thread_complete) { send = prev_send + sent; continue; } #endif wev->ready = 0; return in; } if (send >= limit || in == NULL) { return in; } } }