Mercurial > hg > nginx-quic
view src/os/unix/ngx_readv_chain.c @ 8651:7189cb2b4c5d
Version bump.
author | Roman Arutyunyan <arut@nginx.com> |
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date | Tue, 14 Sep 2021 12:12:02 +0300 |
parents | 7f5e3595caff |
children | 5119c8150478 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> ssize_t ngx_readv_chain(ngx_connection_t *c, ngx_chain_t *chain, off_t limit) { u_char *prev; ssize_t n, size; ngx_err_t err; ngx_array_t vec; ngx_event_t *rev; struct iovec *iov, iovs[NGX_IOVS_PREALLOCATE]; rev = c->read; #if (NGX_HAVE_KQUEUE) if (ngx_event_flags & NGX_USE_KQUEUE_EVENT) { ngx_log_debug3(NGX_LOG_DEBUG_EVENT, c->log, 0, "readv: eof:%d, avail:%d, err:%d", rev->pending_eof, rev->available, rev->kq_errno); if (rev->available == 0) { if (rev->pending_eof) { rev->ready = 0; rev->eof = 1; ngx_log_error(NGX_LOG_INFO, c->log, rev->kq_errno, "kevent() reported about an closed connection"); if (rev->kq_errno) { rev->error = 1; ngx_set_socket_errno(rev->kq_errno); return NGX_ERROR; } return 0; } else { return NGX_AGAIN; } } } #endif #if (NGX_HAVE_EPOLLRDHUP) if (ngx_event_flags & NGX_USE_EPOLL_EVENT) { ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, "readv: eof:%d, avail:%d", rev->pending_eof, rev->available); if (rev->available == 0 && !rev->pending_eof) { return NGX_AGAIN; } } #endif prev = NULL; iov = NULL; size = 0; vec.elts = iovs; vec.nelts = 0; vec.size = sizeof(struct iovec); vec.nalloc = NGX_IOVS_PREALLOCATE; vec.pool = c->pool; /* coalesce the neighbouring bufs */ while (chain) { n = chain->buf->end - chain->buf->last; if (limit) { if (size >= limit) { break; } if (size + n > limit) { n = (ssize_t) (limit - size); } } if (prev == chain->buf->last) { iov->iov_len += n; } else { if (vec.nelts == vec.nalloc) { break; } iov = ngx_array_push(&vec); if (iov == NULL) { return NGX_ERROR; } iov->iov_base = (void *) chain->buf->last; iov->iov_len = n; } size += n; prev = chain->buf->end; chain = chain->next; } ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, "readv: %ui, last:%uz", vec.nelts, iov->iov_len); do { n = readv(c->fd, (struct iovec *) vec.elts, vec.nelts); if (n == 0) { rev->ready = 0; rev->eof = 1; #if (NGX_HAVE_KQUEUE) /* * on FreeBSD readv() may return 0 on closed socket * even if kqueue reported about available data */ if (ngx_event_flags & NGX_USE_KQUEUE_EVENT) { rev->available = 0; } #endif return 0; } if (n > 0) { #if (NGX_HAVE_KQUEUE) if (ngx_event_flags & NGX_USE_KQUEUE_EVENT) { rev->available -= n; /* * rev->available may be negative here because some additional * bytes may be received between kevent() and readv() */ if (rev->available <= 0) { if (!rev->pending_eof) { rev->ready = 0; } rev->available = 0; } return n; } #endif #if (NGX_HAVE_FIONREAD) if (rev->available >= 0) { rev->available -= n; /* * negative rev->available means some additional bytes * were received between kernel notification and readv(), * and therefore ev->ready can be safely reset even for * edge-triggered event methods */ if (rev->available < 0) { rev->available = 0; rev->ready = 0; } ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "readv: avail:%d", rev->available); } else if (n == size) { if (ngx_socket_nread(c->fd, &rev->available) == -1) { n = ngx_connection_error(c, ngx_socket_errno, ngx_socket_nread_n " failed"); break; } ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "readv: avail:%d", rev->available); } #endif #if (NGX_HAVE_EPOLLRDHUP) if ((ngx_event_flags & NGX_USE_EPOLL_EVENT) && ngx_use_epoll_rdhup) { if (n < size) { if (!rev->pending_eof) { rev->ready = 0; } rev->available = 0; } return n; } #endif if (n < size && !(ngx_event_flags & NGX_USE_GREEDY_EVENT)) { rev->ready = 0; } return n; } err = ngx_socket_errno; if (err == NGX_EAGAIN || err == NGX_EINTR) { ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, "readv() not ready"); n = NGX_AGAIN; } else { n = ngx_connection_error(c, err, "readv() failed"); break; } } while (err == NGX_EINTR); rev->ready = 0; if (n == NGX_ERROR) { c->read->error = 1; } return n; }