Mercurial > hg > nginx-quic
view src/os/unix/ngx_linux_aio_read.c @ 4749:613750237b36
Entity tags: the "etag" directive.
It allows to disable generation of nginx's own entity tags, while
still handling ETags in cache properly. This may be useful e.g.
if one want to serve static files from servers with different ETag
generation algorithms.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 09 Jul 2012 14:53:42 +0000 |
parents | d620f497c50f |
children | ccad84a174e0 |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> extern int ngx_eventfd; extern aio_context_t ngx_aio_ctx; static void ngx_file_aio_event_handler(ngx_event_t *ev); static int io_submit(aio_context_t ctx, long n, struct iocb **paiocb) { return syscall(SYS_io_submit, ctx, n, paiocb); } ssize_t ngx_file_aio_read(ngx_file_t *file, u_char *buf, size_t size, off_t offset, ngx_pool_t *pool) { ngx_err_t err; struct iocb *piocb[1]; ngx_event_t *ev; ngx_event_aio_t *aio; if (!ngx_file_aio) { return ngx_read_file(file, buf, size, offset); } aio = file->aio; if (aio == NULL) { aio = ngx_pcalloc(pool, sizeof(ngx_event_aio_t)); if (aio == NULL) { return NGX_ERROR; } aio->file = file; aio->fd = file->fd; aio->event.data = aio; aio->event.ready = 1; aio->event.log = file->log; file->aio = aio; } ev = &aio->event; if (!ev->ready) { ngx_log_error(NGX_LOG_ALERT, file->log, 0, "second aio post for \"%V\"", &file->name); return NGX_AGAIN; } ngx_log_debug4(NGX_LOG_DEBUG_CORE, file->log, 0, "aio complete:%d @%O:%z %V", ev->complete, offset, size, &file->name); if (ev->complete) { ev->active = 0; ev->complete = 0; if (aio->res >= 0) { ngx_set_errno(0); return aio->res; } ngx_set_errno(-aio->res); ngx_log_error(NGX_LOG_CRIT, file->log, ngx_errno, "aio read \"%s\" failed", file->name.data); return NGX_ERROR; } ngx_memzero(&aio->aiocb, sizeof(struct iocb)); aio->aiocb.aio_data = (uint64_t) (uintptr_t) ev; aio->aiocb.aio_lio_opcode = IOCB_CMD_PREAD; aio->aiocb.aio_fildes = file->fd; aio->aiocb.aio_buf = (uint64_t) (uintptr_t) buf; aio->aiocb.aio_nbytes = size; aio->aiocb.aio_offset = offset; aio->aiocb.aio_flags = IOCB_FLAG_RESFD; aio->aiocb.aio_resfd = ngx_eventfd; ev->handler = ngx_file_aio_event_handler; piocb[0] = &aio->aiocb; if (io_submit(ngx_aio_ctx, 1, piocb) == 1) { ev->active = 1; ev->ready = 0; ev->complete = 0; return NGX_AGAIN; } err = ngx_errno; if (err == NGX_EAGAIN) { return ngx_read_file(file, buf, size, offset); } ngx_log_error(NGX_LOG_CRIT, file->log, err, "io_submit(\"%V\") failed", &file->name); if (err == NGX_ENOSYS) { ngx_file_aio = 0; return ngx_read_file(file, buf, size, offset); } return NGX_ERROR; } static void ngx_file_aio_event_handler(ngx_event_t *ev) { ngx_event_aio_t *aio; aio = ev->data; ngx_log_debug2(NGX_LOG_DEBUG_CORE, ev->log, 0, "aio event handler fd:%d %V", aio->fd, &aio->file->name); aio->handler(ev); }