Mercurial > hg > nginx
view src/os/unix/ngx_writev_chain.c @ 6339:67422a0a8ed2 stable-1.8
Events: made a failure to create a notification channel non-fatal.
This may happen if eventfd() returns ENOSYS, notably seen on CentOS 5.4.
Such a failure will now just disable the notification mechanism and let
the callers cope with it, instead of failing to start worker processes.
If thread pools are not configured, this can safely be ignored.
author | Ruslan Ermilov <ru@nginx.com> |
---|---|
date | Wed, 06 May 2015 17:04:00 +0300 |
parents | 2c64b69daec5 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> ngx_chain_t * ngx_writev_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit) { ssize_t n, sent; off_t send, prev_send; ngx_chain_t *cl; ngx_event_t *wev; ngx_iovec_t vec; struct iovec iovs[NGX_IOVS_PREALLOCATE]; 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; vec.iovs = iovs; vec.nalloc = NGX_IOVS_PREALLOCATE; for ( ;; ) { prev_send = send; /* create the iovec and coalesce the neighbouring bufs */ cl = ngx_output_chain_to_iovec(&vec, in, limit - send, c->log); if (cl == NGX_CHAIN_ERROR) { return NGX_CHAIN_ERROR; } if (cl && cl->buf->in_file) { ngx_log_error(NGX_LOG_ALERT, c->log, 0, "file buf in writev " "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; } send += vec.size; n = ngx_writev(c, &vec); if (n == NGX_ERROR) { return NGX_CHAIN_ERROR; } sent = (n == NGX_AGAIN) ? 0 : n; c->sent += sent; in = ngx_chain_update_sent(in, sent); if (send - prev_send != sent) { wev->ready = 0; return in; } if (send >= limit || in == NULL) { return in; } } } ngx_chain_t * ngx_output_chain_to_iovec(ngx_iovec_t *vec, ngx_chain_t *in, size_t limit, ngx_log_t *log) { size_t total, size; u_char *prev; ngx_uint_t n; struct iovec *iov; iov = NULL; prev = NULL; total = 0; n = 0; for ( /* void */ ; in && total < limit; in = in->next) { if (ngx_buf_special(in->buf)) { continue; } if (in->buf->in_file) { break; } if (!ngx_buf_in_memory(in->buf)) { ngx_log_error(NGX_LOG_ALERT, log, 0, "bad buf in output chain " "t:%d r:%d f:%d %p %p-%p %p %O-%O", in->buf->temporary, in->buf->recycled, in->buf->in_file, in->buf->start, in->buf->pos, in->buf->last, in->buf->file, in->buf->file_pos, in->buf->file_last); ngx_debug_point(); return NGX_CHAIN_ERROR; } size = in->buf->last - in->buf->pos; if (size > limit - total) { size = limit - total; } if (prev == in->buf->pos) { iov->iov_len += size; } else { if (n == vec->nalloc) { break; } iov = &vec->iovs[n++]; iov->iov_base = (void *) in->buf->pos; iov->iov_len = size; } prev = in->buf->pos + size; total += size; } vec->count = n; vec->size = total; return in; } ssize_t ngx_writev(ngx_connection_t *c, ngx_iovec_t *vec) { ssize_t n; ngx_err_t err; eintr: n = writev(c->fd, vec->iovs, vec->count); ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, "writev: %z of %uz", n, vec->size); if (n == -1) { err = ngx_errno; switch (err) { case NGX_EAGAIN: ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, "writev() not ready"); return NGX_AGAIN; case NGX_EINTR: ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, "writev() was interrupted"); goto eintr; default: c->write->error = 1; ngx_connection_error(c, err, "writev() failed"); return NGX_ERROR; } } return n; }