nginx/src/os/unix/ngx_linux_sendfile_chain.c
2007-07-29 18:24:53 +00:00

372 lines
9.9 KiB
C

/*
* Copyright (C) Igor Sysoev
*/
#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>
/*
* On Linux up to 2.4.21 sendfile() (syscall #187) works with 32-bit
* offsets only, and the including <sys/sendfile.h> breaks the compiling,
* if off_t is 64 bit wide. So we use own sendfile() definition, where offset
* parameter is int32_t, and use sendfile() for the file parts below 2G only,
* see src/os/unix/ngx_linux_config.h
*
* Linux 2.4.21 has the new sendfile64() syscall #239.
*
* On Linux up to 2.6.16 sendfile() does not allow to pass the count parameter
* more than 2G-1 bytes even on 64-bit platforms: it returns EINVAL,
* so we limit it to 2G-1 bytes.
*/
#define NGX_SENDFILE_LIMIT 2147483647L
#if (IOV_MAX > 64)
#define NGX_HEADERS 64
#else
#define NGX_HEADERS IOV_MAX
#endif
ngx_chain_t *
ngx_linux_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit)
{
int rc, tcp_nodelay;
off_t size, send, prev_send, aligned, sent, fprev;
u_char *prev;
size_t file_size;
ngx_err_t err;
ngx_buf_t *file;
ngx_uint_t eintr, complete;
ngx_array_t header;
ngx_event_t *wev;
ngx_chain_t *cl;
struct iovec *iov, headers[NGX_HEADERS];
#if (NGX_HAVE_SENDFILE64)
off_t offset;
#else
int32_t offset;
#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_LIMIT - ngx_pagesize)) {
limit = NGX_SENDFILE_LIMIT - ngx_pagesize;
}
send = 0;
header.elts = headers;
header.size = sizeof(struct iovec);
header.nalloc = NGX_HEADERS;
header.pool = c->pool;
for ( ;; ) {
file = NULL;
file_size = 0;
eintr = 0;
complete = 0;
prev_send = send;
header.nelts = 0;
prev = NULL;
iov = NULL;
/* create the iovec and coalesce the neighbouring bufs */
for (cl = in;
cl && header.nelts < IOV_MAX && send < limit;
cl = cl->next)
{
if (ngx_buf_special(cl->buf)) {
continue;
}
#if 1
if (!ngx_buf_in_memory(cl->buf) && !cl->buf->in_file) {
ngx_log_error(NGX_LOG_ALERT, c->log, 0,
"zero size buf in sendfile "
"t:%d r:%d f:%d %p %p-%p %p %O-%O",
cl->buf->temporary,
cl->buf->recycled,
cl->buf->in_file,
cl->buf->start,
cl->buf->pos,
cl->buf->last,
cl->buf->file,
cl->buf->file_pos,
cl->buf->file_last);
ngx_debug_point();
return NGX_CHAIN_ERROR;
}
#endif
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;
send += size;
}
/* set TCP_CORK if there is a header before a file */
if (c->tcp_nopush == NGX_TCP_NOPUSH_UNSET
&& header.nelts != 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_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_HTTP, c->log, 0,
"no tcp_nodelay");
}
}
if (c->tcp_nodelay == NGX_TCP_NODELAY_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_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.nelts == 0 && 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) {
#if 1
if (file_size == 0) {
ngx_debug_point();
return NGX_CHAIN_ERROR;
}
#endif
#if (NGX_HAVE_SENDFILE64)
offset = file->file_pos;
#else
offset = (int32_t) file->file_pos;
#endif
ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
"sendfile: @%O %uz", file->file_pos, file_size);
rc = sendfile(c->fd, file->file->fd, &offset, file_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,
"sendfile() is not ready");
} else {
wev->error = 1;
ngx_connection_error(c, err, "sendfile() failed");
return NGX_CHAIN_ERROR;
}
}
sent = rc > 0 ? rc : 0;
ngx_log_debug4(NGX_LOG_DEBUG_EVENT, c->log, 0,
"sendfile: %d, @%O %O:%uz",
rc, file->file_pos, sent, file_size);
} else {
rc = writev(c->fd, header.elts, header.nelts);
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;
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "writev: %O", sent);
}
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 (eintr) {
continue;
}
if (!complete) {
wev->ready = 0;
return cl;
}
if (send >= limit || cl == NULL) {
return cl;
}
in = cl;
}
}