nginx/src/os/unix/ngx_freebsd_sendfile_chain.c
2004-03-29 17:43:58 +00:00

325 lines
9.2 KiB
C

/*
* Copyright (C) 2002-2004 Igor Sysoev, http://sysoev.ru/en/
*/
#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>
/*
* Although FreeBSD sendfile() allows to pass a header and a trailer
* it never sends a header with a part of the file in one packet until
* FreeBSD 5.2-STABLE. Besides over the fast ethernet connection sendfile()
* can send the partially filled packets, i.e. the 8 file pages can 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 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 can 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)
{
int rc;
u_char *prev;
off_t sent, fprev;
size_t hsize, fsize;
ssize_t size;
ngx_int_t eintr, eagain;
struct iovec *iov;
struct sf_hdtr hdtr;
ngx_err_t err;
ngx_hunk_t *file;
ngx_array_t header, trailer;
ngx_event_t *wev;
ngx_chain_t *cl, *tail;
wev = c->write;
if (!wev->ready) {
return in;
}
#if (HAVE_KQUEUE)
if ((ngx_event_flags & NGX_HAVE_KQUEUE_EVENT) && wev->kq_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
do {
file = NULL;
fsize = 0;
hsize = 0;
eintr = 0;
eagain = 0;
ngx_init_array(header, c->pool, 10, sizeof(struct iovec),
NGX_CHAIN_ERROR);
ngx_init_array(trailer, c->pool, 10, sizeof(struct iovec),
NGX_CHAIN_ERROR);
/* create the header iovec and coalesce the neighbouring hunks */
prev = NULL;
iov = NULL;
for (cl = in; cl && header.nelts < IOV_MAX; cl = cl->next) {
if (ngx_hunk_special(cl->hunk)) {
continue;
}
if (!ngx_hunk_in_memory_only(cl->hunk)) {
break;
}
if (prev == cl->hunk->pos) {
iov->iov_len += cl->hunk->last - cl->hunk->pos;
} else {
ngx_test_null(iov, ngx_push_array(&header), NGX_CHAIN_ERROR);
iov->iov_base = (void *) cl->hunk->pos;
iov->iov_len = cl->hunk->last - cl->hunk->pos;
}
prev = cl->hunk->last;
hsize += cl->hunk->last - cl->hunk->pos;
}
/* get the file hunk */
if (cl && (cl->hunk->type & NGX_HUNK_FILE)) {
file = cl->hunk;
fsize = (size_t) (file->file_last - file->file_pos);
fprev = file->file_last;
cl = cl->next;
/* coalesce the neighbouring file hunks */
while (cl && (cl->hunk->type & NGX_HUNK_FILE)) {
if (file->file->fd != cl->hunk->file->fd
|| fprev != cl->hunk->file_pos)
{
break;
}
fsize += (size_t) (cl->hunk->file_last - cl->hunk->file_pos);
fprev = cl->hunk->file_last;
cl = cl->next;
}
}
if (file) {
/* create the tailer iovec and coalesce the neighbouring hunks */
prev = NULL;
iov = NULL;
for ( /* void */; cl && trailer.nelts < IOV_MAX; cl = cl->next) {
if (ngx_hunk_special(cl->hunk)) {
continue;
}
if (!ngx_hunk_in_memory_only(cl->hunk)) {
break;
}
if (prev == cl->hunk->pos) {
iov->iov_len += cl->hunk->last - cl->hunk->pos;
} else {
ngx_test_null(iov, ngx_push_array(&trailer),
NGX_CHAIN_ERROR);
iov->iov_base = (void *) cl->hunk->pos;
iov->iov_len = cl->hunk->last - cl->hunk->pos;
}
prev = cl->hunk->last;
}
}
/*
* the tail is the rest of the chain that exceeded
* a single sendfile() capability
*/
tail = cl;
if (file) {
if (ngx_freebsd_use_tcp_nopush && c->tcp_nopush == 0) {
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 = 1;
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;
}
c->sent += sent;
for (cl = in; cl; cl = cl->next) {
if (ngx_hunk_special(cl->hunk)) {
continue;
}
if (sent == 0) {
break;
}
size = ngx_hunk_size(cl->hunk);
if (sent >= size) {
sent -= size;
if (cl->hunk->type & NGX_HUNK_IN_MEMORY) {
cl->hunk->pos = cl->hunk->last;
}
if (cl->hunk->type & NGX_HUNK_FILE) {
cl->hunk->file_pos = cl->hunk->file_last;
}
continue;
}
if (cl->hunk->type & NGX_HUNK_IN_MEMORY) {
cl->hunk->pos += sent;
}
if (cl->hunk->type & NGX_HUNK_FILE) {
cl->hunk->file_pos += sent;
}
break;
}
in = cl;
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;
break;
}
/* "tail == in" means that a single sendfile() is complete */
} while ((tail && tail == in) || eintr);
if (in) {
wev->ready = 0;
}
return in;
}