Mercurial > hg > nginx-vendor-1-0
diff src/os/unix/ngx_freebsd_sendfile_chain.c @ 0:f0b350454894 NGINX_0_1_0
nginx 0.1.0
*) The first public version.
author | Igor Sysoev <http://sysoev.ru> |
---|---|
date | Mon, 04 Oct 2004 00:00:00 +0400 |
parents | |
children | 4b2dafa26fe2 |
line wrap: on
line diff
new file mode 100644 --- /dev/null +++ b/src/os/unix/ngx_freebsd_sendfile_chain.c @@ -0,0 +1,380 @@ + +/* + * Copyright (C) Igor Sysoev + */ + + +#include <ngx_config.h> +#include <ngx_core.h> +#include <ngx_event.h> + + +/* + * Although FreeBSD sendfile() allows to pass a header and a trailer + * it can not 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. + * + * So 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 the 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. + */ + + +#define NGX_HEADERS 8 +#define NGX_TRAILERS 4 + + +ngx_chain_t *ngx_freebsd_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in, + off_t limit) +{ + int rc; + u_char *prev; + off_t fprev, sent, send, sprev, aligned; + size_t hsize, fsize; + ssize_t size; + ngx_uint_t eintr, eagain, complete; + ngx_err_t err; + ngx_buf_t *file; + ngx_array_t header, trailer; + ngx_event_t *wev; + ngx_chain_t *cl; + struct sf_hdtr hdtr; + struct iovec *iov, headers[NGX_HEADERS], trailers[NGX_TRAILERS]; + + wev = c->write; + + if (!wev->ready) { + return in; + } + +#if (HAVE_KQUEUE) + + if ((ngx_event_flags & NGX_HAVE_KQUEUE_EVENT) && wev->pending_eof) { + ngx_log_error(NGX_LOG_INFO, c->log, wev->kq_errno, + "kevent() reported about an closed connection"); + + wev->error = 1; + return NGX_CHAIN_ERROR; + } + +#endif + + send = 0; + eagain = 0; + + header.elts = headers; + header.size = sizeof(struct iovec); + header.nalloc = NGX_HEADERS; + header.pool = c->pool; + + trailer.elts = trailers; + trailer.size = sizeof(struct iovec); + trailer.nalloc = NGX_TRAILERS; + trailer.pool = c->pool; + + for ( ;; ) { + file = NULL; + fsize = 0; + hsize = 0; + eintr = 0; + complete = 0; + sprev = send; + + header.nelts = 0; + trailer.nelts = 0; + + /* create the header iovec and coalesce the neighbouring bufs */ + + prev = NULL; + iov = NULL; + + for (cl = in; + cl && header.nelts < IOV_MAX && send < limit; + cl = cl->next) + { + if (ngx_buf_special(cl->buf)) { + continue; + } + + if (!ngx_buf_in_memory_only(cl->buf)) { + break; + } + + size = cl->buf->last - cl->buf->pos; + + if (send + size > limit) { + size = limit - send; + } + + if (prev == cl->buf->pos) { + iov->iov_len += size; + + } else { + if (!(iov = ngx_array_push(&header))) { + return NGX_CHAIN_ERROR; + } + + iov->iov_base = (void *) cl->buf->pos; + iov->iov_len = size; + } + + prev = cl->buf->pos + size; + hsize += size; + send += size; + } + + /* get the file buf */ + + if (cl && cl->buf->in_file && send < limit) { + file = cl->buf; + + /* coalesce the neighbouring file bufs */ + + do { + size = (size_t) (cl->buf->file_last - cl->buf->file_pos); + + if (send + size > limit) { + size = limit - send; + + aligned = (cl->buf->file_pos + size + ngx_pagesize - 1) + & ~(ngx_pagesize - 1); + + if (aligned <= cl->buf->file_last) { + size = aligned - cl->buf->file_pos; + } + } + + fsize += size; + send += size; + fprev = cl->buf->file_pos + size; + cl = cl->next; + + } while (cl + && cl->buf->in_file + && send < limit + && file->file->fd == cl->buf->file->fd + && fprev == cl->buf->file_pos); + } + + if (file) { + /* create the tailer iovec and coalesce the neighbouring bufs */ + + prev = NULL; + iov = NULL; + + for (/* void */; + cl && header.nelts < IOV_MAX && send < limit; + cl = cl->next) + { + if (ngx_buf_special(cl->buf)) { + continue; + } + + if (!ngx_buf_in_memory_only(cl->buf)) { + break; + } + + size = cl->buf->last - cl->buf->pos; + + if (send + size > limit) { + size = limit - send; + } + + if (prev == cl->buf->pos) { + iov->iov_len += size; + + } else { + if (!(iov = ngx_array_push(&trailer))) { + return NGX_CHAIN_ERROR; + } + + iov->iov_base = (void *) cl->buf->pos; + iov->iov_len = size; + } + + prev = cl->buf->pos + size; + send += size; + } + } + + if (file) { + + if (ngx_freebsd_use_tcp_nopush + && c->tcp_nopush == NGX_TCP_NOPUSH_UNSET) + { + + if (ngx_tcp_nopush(c->fd) == NGX_ERROR) { + err = ngx_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; + 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"); + } + } + + hdtr.headers = (struct iovec *) header.elts; + hdtr.hdr_cnt = header.nelts; + hdtr.trailers = (struct iovec *) trailer.elts; + hdtr.trl_cnt = trailer.nelts; + + /* + * the "nbytes bug" of the old sendfile() syscall: + * http://www.freebsd.org/cgi/query-pr.cgi?pr=33771 + */ + + if (ngx_freebsd_sendfile_nbytes_bug == 0) { + hsize = 0; + } + + sent = 0; + + rc = sendfile(file->file->fd, c->fd, file->file_pos, + fsize + hsize, &hdtr, &sent, 0); + + if (rc == -1) { + err = ngx_errno; + + if (err == NGX_EAGAIN || err == NGX_EINTR) { + if (err == NGX_EINTR) { + eintr = 1; + + } else { + eagain = 1; + } + + ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, err, + "sendfile() sent only " OFF_T_FMT " bytes", + sent); + + } else { + wev->error = 1; + ngx_connection_error(c, err, "sendfile() failed"); + return NGX_CHAIN_ERROR; + } + } + + ngx_log_debug4(NGX_LOG_DEBUG_EVENT, c->log, 0, + "sendfile: %d, @" OFF_T_FMT " " OFF_T_FMT ":%d", + rc, file->file_pos, sent, fsize + hsize); + + } else { + rc = writev(c->fd, header.elts, header.nelts); + + ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, + "writev: %d of " SIZE_T_FMT, rc, hsize); + + if (rc == -1) { + err = ngx_errno; + + if (err == NGX_EAGAIN || err == NGX_EINTR) { + if (err == NGX_EINTR) { + eintr = 1; + } + + ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, + "writev() not ready"); + + } else { + wev->error = 1; + ngx_connection_error(c, err, "writev() failed"); + return NGX_CHAIN_ERROR; + } + } + + sent = rc > 0 ? rc : 0; + } + + if (send - sprev == sent) { + complete = 1; + } + + c->sent += sent; + + for (cl = in; cl; cl = cl->next) { + + if (ngx_buf_special(cl->buf)) { + continue; + } + + if (sent == 0) { + break; + } + + size = ngx_buf_size(cl->buf); + + if (sent >= size) { + sent -= size; + + if (ngx_buf_in_memory(cl->buf)) { + cl->buf->pos = cl->buf->last; + } + + if (cl->buf->in_file) { + cl->buf->file_pos = cl->buf->file_last; + } + + continue; + } + + if (ngx_buf_in_memory(cl->buf)) { + cl->buf->pos += sent; + } + + if (cl->buf->in_file) { + cl->buf->file_pos += sent; + } + + break; + } + + if (eagain) { + + /* + * sendfile() can return EAGAIN even if it has sent + * a whole file part but the successive sendfile() call would + * return EAGAIN right away and would not send anything. + * We use it as a hint. + */ + + wev->ready = 0; + return cl; + } + + if (eintr) { + continue; + } + + if (!complete) { + wev->ready = 0; + return cl; + } + + if (send >= limit || cl == NULL) { + return cl; + } + + in = cl; + } +}