3 * Copyright (C) Igor Sysoev
7 #include <ngx_config.h>
15 #define NGX_IOVS IOV_MAX
20 ngx_writev_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit)
23 ssize_t n, size, sent;
24 off_t send, prev_send;
25 ngx_uint_t eintr, complete;
30 struct iovec *iov, iovs[NGX_IOVS];
40 if ((ngx_event_flags & NGX_USE_KQUEUE_EVENT) && wev->pending_eof) {
41 (void) ngx_connection_error(c, wev->kq_errno,
42 "kevent() reported about an closed connection");
44 return NGX_CHAIN_ERROR;
49 /* the maximum limit size is the maximum size_t value - the page size */
51 if (limit == 0 || limit > (off_t) (NGX_MAX_SIZE_T_VALUE - ngx_pagesize)) {
52 limit = NGX_MAX_SIZE_T_VALUE - ngx_pagesize;
59 vec.size = sizeof(struct iovec);
60 vec.nalloc = NGX_IOVS;
71 /* create the iovec and coalesce the neighbouring bufs */
73 for (cl = in; cl && vec.nelts < IOV_MAX && send < limit; cl = cl->next)
75 if (ngx_buf_special(cl->buf)) {
80 if (!ngx_buf_in_memory(cl->buf)) {
85 size = cl->buf->last - cl->buf->pos;
87 if (send + size > limit) {
88 size = (ssize_t) (limit - send);
91 if (prev == cl->buf->pos) {
95 iov = ngx_array_push(&vec);
97 return NGX_CHAIN_ERROR;
100 iov->iov_base = (void *) cl->buf->pos;
104 prev = cl->buf->pos + size;
108 n = writev(c->fd, vec.elts, vec.nelts);
113 if (err == NGX_EAGAIN || err == NGX_EINTR) {
114 if (err == NGX_EINTR) {
118 ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err,
119 "writev() not ready");
123 (void) ngx_connection_error(c, err, "writev() failed");
124 return NGX_CHAIN_ERROR;
128 sent = n > 0 ? n : 0;
130 ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "writev: %z", sent);
132 if (send - prev_send == sent) {
138 for (cl = in; cl; cl = cl->next) {
140 if (ngx_buf_special(cl->buf)) {
148 size = cl->buf->last - cl->buf->pos;
152 cl->buf->pos = cl->buf->last;
157 cl->buf->pos += sent;
171 if (send >= limit || cl == NULL) {