Mercurial > hg > nginx-ranges
view src/os/unix/ngx_freebsd_sendfile_chain.c @ 391:1d9bef53cd8e
Range filter: late_ranges functionality.
Add one more filtering point after postpone filter. This allows to serve
range capable replies with subrequests. It's not as efficient as range
filtering for static data (i.e. doesn't save us from reading data from
disk if some filter needs them in memory), but it may save some network
bandwidth for us and for our users.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 21 Jul 2008 05:33:01 +0400 |
parents | f7cd062ee035 |
children | d41628eb4d0a |
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/* * 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. * * Threfore 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. */ #if (IOV_MAX > 64) #define NGX_HEADERS 64 #define NGX_TRAILERS 64 #else #define NGX_HEADERS IOV_MAX #define NGX_TRAILERS IOV_MAX #endif 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 size, send, prev_send, aligned, sent, fprev; size_t header_size, file_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 (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; 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; file_size = 0; header_size = 0; eintr = 0; complete = 0; prev_send = 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_t) size; } else { iov = ngx_array_push(&header); if (iov == NULL) { return NGX_CHAIN_ERROR; } iov->iov_base = (void *) cl->buf->pos; iov->iov_len = (size_t) size; } prev = cl->buf->pos + (size_t) size; header_size += (size_t) size; send += size; } if (cl && cl->buf->in_file && send < limit) { file = cl->buf; /* coalesce the neighbouring file bufs */ do { size = cl->buf->file_last - cl->buf->file_pos; if (send + size > limit) { size = limit - send; aligned = (cl->buf->file_pos + size + ngx_pagesize - 1) & ~((off_t) ngx_pagesize - 1); if (aligned <= cl->buf->file_last) { size = aligned - cl->buf->file_pos; } } file_size += (size_t) 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; while (cl && header.nelts < IOV_MAX && send < limit) { if (ngx_buf_special(cl->buf)) { cl = cl->next; 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_t) size; } else { iov = ngx_array_push(&trailer); if (iov == NULL) { return NGX_CHAIN_ERROR; } iov->iov_base = (void *) cl->buf->pos; iov->iov_len = (size_t) size; } prev = cl->buf->pos + (size_t) size; send += size; cl = cl->next; } } 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; (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"); } } 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) { header_size = 0; } sent = 0; rc = sendfile(file->file->fd, c->fd, file->file_pos, file_size + header_size, &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 %O bytes", sent); } else { wev->error = 1; (void) ngx_connection_error(c, err, "sendfile() failed"); return NGX_CHAIN_ERROR; } } /* * sendfile() in FreeBSD 3.x-4.x may return value >= 0 * on success, although only 0 is documented */ 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", file->file->name.data); 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 { rc = writev(c->fd, header.elts, header.nelts); ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, "writev: %d of %uz", rc, header_size); 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 - prev_send == 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 += (size_t) sent; } if (cl->buf->in_file) { cl->buf->file_pos += sent; } break; } 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 cl; } if (eintr) { continue; } if (!complete) { wev->ready = 0; return cl; } if (send >= limit || cl == NULL) { return cl; } in = cl; } }