Mercurial > hg > nginx
view src/os/win32/ngx_service.c @ 7583:efd71d49bde0
Events: available bytes calculation via ioctl(FIONREAD).
This makes it possible to avoid looping for a long time while working
with a fast enough peer when data are added to the socket buffer faster
than we are able to read and process them (ticket #1431). This is
basically what we already do on FreeBSD with kqueue, where information
about the number of bytes in the socket buffer is returned by
the kevent() call.
With other event methods rev->available is now set to -1 when the socket
is ready for reading. Later in ngx_recv() and ngx_recv_chain(), if
full buffer is received, real number of bytes in the socket buffer is
retrieved using ioctl(FIONREAD). Reading more than this number of bytes
ensures that even with edge-triggered event methods the event will be
triggered again, so it is safe to stop processing of the socket and
switch to other connections.
Using ioctl(FIONREAD) only after reading a full buffer is an optimization.
With this approach we only call ioctl(FIONREAD) when there are at least
two recv()/readv() calls.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Thu, 17 Oct 2019 16:02:19 +0300 |
parents | a1caf3989b49 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #define NGX_SERVICE_CONTROL_SHUTDOWN 128 #define NGX_SERVICE_CONTROL_REOPEN 129 SERVICE_TABLE_ENTRY st[] = { { "nginx", service_main }, { NULL, NULL } }; ngx_int_t ngx_service(ngx_log_t *log) { /* primary thread */ /* StartServiceCtrlDispatcher() should be called within 30 seconds */ if (StartServiceCtrlDispatcher(st) == 0) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "StartServiceCtrlDispatcher() failed"); return NGX_ERROR; } return NGX_OK; } void service_main(u_int argc, char **argv) { SERVICE_STATUS status; SERVICE_STATUS_HANDLE service; /* thread spawned by SCM */ service = RegisterServiceCtrlHandlerEx("nginx", service_handler, ctx); if (service == INVALID_HANDLE_VALUE) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "RegisterServiceCtrlHandlerEx() failed"); return; } status.dwServiceType = SERVICE_WIN32_OWN_PROCESS; status.dwCurrentState = SERVICE_START_PENDING; status.dwControlsAccepted = SERVICE_ACCEPT_STOP |SERVICE_ACCEPT_PARAMCHANGE; status.dwWin32ExitCode = NO_ERROR; status.dwServiceSpecificExitCode = 0; status.dwCheckPoint = 1; status.dwWaitHint = 2000; /* SetServiceStatus() should be called within 80 seconds */ if (SetServiceStatus(service, &status) == 0) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "SetServiceStatus() failed"); return; } /* init */ status.dwCurrentState = SERVICE_RUNNING; status.dwCheckPoint = 0; status.dwWaitHint = 0; if (SetServiceStatus(service, &status) == 0) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "SetServiceStatus() failed"); return; } /* call master or worker loop */ /* * master should use event notification and look status * single should use iocp to get notifications from service handler */ } u_int service_handler(u_int control, u_int type, void *data, void *ctx) { /* primary thread */ switch (control) { case SERVICE_CONTROL_INTERROGATE: status = NGX_IOCP_INTERROGATE; break; case SERVICE_CONTROL_STOP: status = NGX_IOCP_STOP; break; case SERVICE_CONTROL_PARAMCHANGE: status = NGX_IOCP_RECONFIGURE; break; case NGX_SERVICE_CONTROL_SHUTDOWN: status = NGX_IOCP_REOPEN; break; case NGX_SERVICE_CONTROL_REOPEN: status = NGX_IOCP_REOPEN; break; default: return ERROR_CALL_NOT_IMPLEMENTED; } if (ngx_single) { if (PostQueuedCompletionStatus(iocp, ... status, ...) == 0) { err = ngx_errno; ngx_log_error(NGX_LOG_ALERT, log, err, "PostQueuedCompletionStatus() failed"); return err; } } else { Event } return NO_ERROR; }