diff options
Diffstat (limited to 'app/nginx/src/os/unix/ngx_linux_sendfile_chain.c')
| -rw-r--r-- | app/nginx/src/os/unix/ngx_linux_sendfile_chain.c | 442 |
1 files changed, 442 insertions, 0 deletions
diff --git a/app/nginx/src/os/unix/ngx_linux_sendfile_chain.c b/app/nginx/src/os/unix/ngx_linux_sendfile_chain.c new file mode 100644 index 0000000..b44724c --- /dev/null +++ b/app/nginx/src/os/unix/ngx_linux_sendfile_chain.c @@ -0,0 +1,442 @@ + +/* + * Copyright (C) Igor Sysoev + * Copyright (C) Nginx, Inc. + */ + + +#include <ngx_config.h> +#include <ngx_core.h> +#include <ngx_event.h> + + +static ssize_t ngx_linux_sendfile(ngx_connection_t *c, ngx_buf_t *file, + size_t size); + +#if (NGX_THREADS) +#include <ngx_thread_pool.h> + +#if !(NGX_HAVE_SENDFILE64) +#error sendfile64() is required! +#endif + +static ssize_t ngx_linux_sendfile_thread(ngx_connection_t *c, ngx_buf_t *file, + size_t size); +static void ngx_linux_sendfile_thread_handler(void *data, ngx_log_t *log); +#endif + + +/* + * 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 + + +ngx_chain_t * +ngx_linux_sendfile_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit) +{ + int tcp_nodelay; + off_t send, prev_send; + size_t file_size, sent; + ssize_t n; + ngx_err_t err; + ngx_buf_t *file; + ngx_event_t *wev; + ngx_chain_t *cl; + ngx_iovec_t header; + struct iovec headers[NGX_IOVS_PREALLOCATE]; + + 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.iovs = headers; + header.nalloc = NGX_IOVS_PREALLOCATE; + + for ( ;; ) { + prev_send = send; + + /* create the iovec and coalesce the neighbouring bufs */ + + cl = ngx_output_chain_to_iovec(&header, in, limit - send, c->log); + + if (cl == NGX_CHAIN_ERROR) { + return NGX_CHAIN_ERROR; + } + + send += header.size; + + /* set TCP_CORK if there is a header before a file */ + + if (c->tcp_nopush == NGX_TCP_NOPUSH_UNSET + && header.count != 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_socket_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_socket_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.count == 0 && cl && cl->buf->in_file && send < limit) { + file = cl->buf; + + /* coalesce the neighbouring file bufs */ + + file_size = (size_t) ngx_chain_coalesce_file(&cl, limit - send); + + send += file_size; +#if 1 + if (file_size == 0) { + ngx_debug_point(); + return NGX_CHAIN_ERROR; + } +#endif + + n = ngx_linux_sendfile(c, file, file_size); + + if (n == NGX_ERROR) { + return NGX_CHAIN_ERROR; + } + + if (n == NGX_DONE) { + /* thread task posted */ + return in; + } + + sent = (n == NGX_AGAIN) ? 0 : n; + + } else { + n = ngx_writev(c, &header); + + 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 (n == NGX_AGAIN) { + wev->ready = 0; + return in; + } + + if ((size_t) (send - prev_send) != sent) { + + /* + * sendfile() on Linux 4.3+ might be interrupted at any time, + * and provides no indication if it was interrupted or not, + * so we have to retry till an explicit EAGAIN + * + * sendfile() in threads can also report less bytes written + * than we are prepared to send now, since it was started in + * some point in the past, so we again have to retry + */ + + send = prev_send + sent; + continue; + } + + if (send >= limit || in == NULL) { + return in; + } + } +} + + +static ssize_t +ngx_linux_sendfile(ngx_connection_t *c, ngx_buf_t *file, size_t size) +{ +#if (NGX_HAVE_SENDFILE64) + off_t offset; +#else + int32_t offset; +#endif + ssize_t n; + ngx_err_t err; + +#if (NGX_THREADS) + + if (file->file->thread_handler) { + return ngx_linux_sendfile_thread(c, file, size); + } + +#endif + +#if (NGX_HAVE_SENDFILE64) + offset = file->file_pos; +#else + offset = (int32_t) file->file_pos; +#endif + +eintr: + + ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0, + "sendfile: @%O %uz", file->file_pos, size); + + n = sendfile(c->fd, file->file->fd, &offset, size); + + if (n == -1) { + err = ngx_errno; + + switch (err) { + case NGX_EAGAIN: + ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, + "sendfile() is not ready"); + return NGX_AGAIN; + + case NGX_EINTR: + ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, + "sendfile() was interrupted"); + goto eintr; + + default: + c->write->error = 1; + ngx_connection_error(c, err, "sendfile() failed"); + return NGX_ERROR; + } + } + + if (n == 0) { + /* + * if sendfile returns zero, then someone has truncated the file, + * so the offset became beyond the end of the file + */ + + ngx_log_error(NGX_LOG_ALERT, c->log, 0, + "sendfile() reported that \"%s\" was truncated at %O", + file->file->name.data, file->file_pos); + + return NGX_ERROR; + } + + ngx_log_debug3(NGX_LOG_DEBUG_EVENT, c->log, 0, "sendfile: %z of %uz @%O", + n, size, file->file_pos); + + return n; +} + + +#if (NGX_THREADS) + +typedef struct { + ngx_buf_t *file; + ngx_socket_t socket; + size_t size; + + size_t sent; + ngx_err_t err; +} ngx_linux_sendfile_ctx_t; + + +static ssize_t +ngx_linux_sendfile_thread(ngx_connection_t *c, ngx_buf_t *file, size_t size) +{ + ngx_event_t *wev; + ngx_thread_task_t *task; + ngx_linux_sendfile_ctx_t *ctx; + + ngx_log_debug3(NGX_LOG_DEBUG_CORE, c->log, 0, + "linux sendfile thread: %d, %uz, %O", + file->file->fd, size, file->file_pos); + + task = c->sendfile_task; + + if (task == NULL) { + task = ngx_thread_task_alloc(c->pool, sizeof(ngx_linux_sendfile_ctx_t)); + if (task == NULL) { + return NGX_ERROR; + } + + task->handler = ngx_linux_sendfile_thread_handler; + + c->sendfile_task = task; + } + + ctx = task->ctx; + wev = c->write; + + if (task->event.complete) { + task->event.complete = 0; + + if (ctx->err == NGX_EAGAIN) { + /* + * if wev->complete is set, this means that a write event + * happened while we were waiting for the thread task, so + * we have to retry sending even on EAGAIN + */ + + if (wev->complete) { + return 0; + } + + return NGX_AGAIN; + } + + if (ctx->err) { + wev->error = 1; + ngx_connection_error(c, ctx->err, "sendfile() failed"); + return NGX_ERROR; + } + + if (ctx->sent == 0) { + /* + * if sendfile returns zero, then someone has truncated the file, + * so the offset became beyond the end of the file + */ + + ngx_log_error(NGX_LOG_ALERT, c->log, 0, + "sendfile() reported that \"%s\" was truncated at %O", + file->file->name.data, file->file_pos); + + return NGX_ERROR; + } + + return ctx->sent; + } + + if (task->event.active && ctx->file == file) { + /* + * tolerate duplicate calls; they can happen due to subrequests + * or multiple calls of the next body filter from a filter + */ + + return NGX_DONE; + } + + ctx->file = file; + ctx->socket = c->fd; + ctx->size = size; + + wev->complete = 0; + + if (file->file->thread_handler(task, file->file) != NGX_OK) { + return NGX_ERROR; + } + + return NGX_DONE; +} + + +static void +ngx_linux_sendfile_thread_handler(void *data, ngx_log_t *log) +{ + ngx_linux_sendfile_ctx_t *ctx = data; + + off_t offset; + ssize_t n; + ngx_buf_t *file; + + ngx_log_debug0(NGX_LOG_DEBUG_CORE, log, 0, "linux sendfile thread handler"); + + file = ctx->file; + offset = file->file_pos; + +again: + + n = sendfile(ctx->socket, file->file->fd, &offset, ctx->size); + + if (n == -1) { + ctx->err = ngx_errno; + + } else { + ctx->sent = n; + ctx->err = 0; + } + +#if 0 + ngx_time_update(); +#endif + + ngx_log_debug4(NGX_LOG_DEBUG_EVENT, log, 0, + "sendfile: %z (err: %d) of %uz @%O", + n, ctx->err, ctx->size, file->file_pos); + + if (ctx->err == NGX_EINTR) { + goto again; + } +} + +#endif /* NGX_THREADS */ |