Mercurial > hg > nginx-quic
view src/os/unix/ngx_linux_sendfile_chain.c @ 5334:03ff14058272
Added safety belt for the case of sending header twice.
The aforementioned situation is abnormal per se and as such it now forces
request termination with appropriate error message.
author | Sergey Kandaurov <pluknet@nginx.com> |
---|---|
date | Tue, 30 Jul 2013 15:04:46 +0400 |
parents | bdb3588681c9 |
children | 188481078faf |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #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_MAXSIZE 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_MAXSIZE - ngx_pagesize)) { limit = NGX_SENDFILE_MAXSIZE - 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 && 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 { if (header.nelts >= IOV_MAX) { break; } 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_EVENT, 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; switch (err) { case NGX_EAGAIN: break; case NGX_EINTR: eintr = 1; break; default: wev->error = 1; ngx_connection_error(c, err, "sendfile() failed"); return NGX_CHAIN_ERROR; } ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, "sendfile() is not ready"); } 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; switch (err) { case NGX_EAGAIN: break; case NGX_EINTR: eintr = 1; break; default: wev->error = 1; ngx_connection_error(c, err, "writev() failed"); return NGX_CHAIN_ERROR; } ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, "writev() not ready"); } 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 ( /* void */ ; in; in = in->next) { if (ngx_buf_special(in->buf)) { continue; } if (sent == 0) { break; } size = ngx_buf_size(in->buf); if (sent >= size) { sent -= size; if (ngx_buf_in_memory(in->buf)) { in->buf->pos = in->buf->last; } if (in->buf->in_file) { in->buf->file_pos = in->buf->file_last; } continue; } if (ngx_buf_in_memory(in->buf)) { in->buf->pos += (size_t) sent; } if (in->buf->in_file) { in->buf->file_pos += sent; } break; } if (eintr) { continue; } if (!complete) { wev->ready = 0; return in; } if (send >= limit || in == NULL) { return in; } } }