Mercurial > hg > nginx
view src/core/ngx_syslog.c @ 6153:4f6efabcb09b
The "reuseport" option of the "listen" directive.
When configured, an individual listen socket on a given address is
created for each worker process. This allows to reduce in-kernel lock
contention on configurations with high accept rates, resulting in better
performance. As of now it works on Linux and DragonFly BSD.
Note that on Linux incoming connection requests are currently tied up
to a specific listen socket, and if some sockets are closed, connection
requests will be reset, see https://lwn.net/Articles/542629/. With
nginx, this may happen if the number of worker processes is reduced.
There is no such problem on DragonFly BSD.
Based on previous work by Sepherosa Ziehau and Yingqi Lu.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Wed, 20 May 2015 15:51:56 +0300 |
parents | 68f64bc17fa4 |
children | a6a2016b8e31 |
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/* * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #define NGX_SYSLOG_MAX_STR \ NGX_MAX_ERROR_STR + sizeof("<255>Jan 01 00:00:00 ") - 1 \ + (NGX_MAXHOSTNAMELEN - 1) + 1 /* space */ \ + 32 /* tag */ + 2 /* colon, space */ static char *ngx_syslog_parse_args(ngx_conf_t *cf, ngx_syslog_peer_t *peer); static ngx_int_t ngx_syslog_init_peer(ngx_syslog_peer_t *peer); static void ngx_syslog_cleanup(void *data); static char *facilities[] = { "kern", "user", "mail", "daemon", "auth", "intern", "lpr", "news", "uucp", "clock", "authpriv", "ftp", "ntp", "audit", "alert", "cron", "local0", "local1", "local2", "local3", "local4", "local5", "local6", "local7", NULL }; /* note 'error/warn' like in nginx.conf, not 'err/warning' */ static char *severities[] = { "emerg", "alert", "crit", "error", "warn", "notice", "info", "debug", NULL }; static ngx_log_t ngx_syslog_dummy_log; static ngx_event_t ngx_syslog_dummy_event; char * ngx_syslog_process_conf(ngx_conf_t *cf, ngx_syslog_peer_t *peer) { peer->pool = cf->pool; peer->facility = NGX_CONF_UNSET_UINT; peer->severity = NGX_CONF_UNSET_UINT; if (ngx_syslog_parse_args(cf, peer) != NGX_CONF_OK) { return NGX_CONF_ERROR; } if (peer->server.sockaddr == NULL) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "no syslog server specified"); return NGX_CONF_ERROR; } if (peer->facility == NGX_CONF_UNSET_UINT) { peer->facility = 23; /* local7 */ } if (peer->severity == NGX_CONF_UNSET_UINT) { peer->severity = 6; /* info */ } if (peer->tag.data == NULL) { ngx_str_set(&peer->tag, "nginx"); } peer->conn.fd = (ngx_socket_t) -1; return NGX_CONF_OK; } static char * ngx_syslog_parse_args(ngx_conf_t *cf, ngx_syslog_peer_t *peer) { u_char *p, *comma, c; size_t len; ngx_str_t *value; ngx_url_t u; ngx_uint_t i; value = cf->args->elts; p = value[1].data + sizeof("syslog:") - 1; for ( ;; ) { comma = (u_char *) ngx_strchr(p, ','); if (comma != NULL) { len = comma - p; *comma = '\0'; } else { len = value[1].data + value[1].len - p; } if (ngx_strncmp(p, "server=", 7) == 0) { if (peer->server.sockaddr != NULL) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate syslog \"server\""); return NGX_CONF_ERROR; } ngx_memzero(&u, sizeof(ngx_url_t)); u.url.data = p + 7; u.url.len = len - 7; u.default_port = 514; if (ngx_parse_url(cf->pool, &u) != NGX_OK) { if (u.err) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%s in syslog server \"%V\"", u.err, &u.url); } return NGX_CONF_ERROR; } peer->server = u.addrs[0]; } else if (ngx_strncmp(p, "facility=", 9) == 0) { if (peer->facility != NGX_CONF_UNSET_UINT) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate syslog \"facility\""); return NGX_CONF_ERROR; } for (i = 0; facilities[i] != NULL; i++) { if (ngx_strcmp(p + 9, facilities[i]) == 0) { peer->facility = i; goto next; } } ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unknown syslog facility \"%s\"", p + 9); return NGX_CONF_ERROR; } else if (ngx_strncmp(p, "severity=", 9) == 0) { if (peer->severity != NGX_CONF_UNSET_UINT) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate syslog \"severity\""); return NGX_CONF_ERROR; } for (i = 0; severities[i] != NULL; i++) { if (ngx_strcmp(p + 9, severities[i]) == 0) { peer->severity = i; goto next; } } ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unknown syslog severity \"%s\"", p + 9); return NGX_CONF_ERROR; } else if (ngx_strncmp(p, "tag=", 4) == 0) { if (peer->tag.data != NULL) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate syslog \"tag\""); return NGX_CONF_ERROR; } /* * RFC 3164: the TAG is a string of ABNF alphanumeric characters * that MUST NOT exceed 32 characters. */ if (len - 4 > 32) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "syslog tag length exceeds 32"); return NGX_CONF_ERROR; } for (i = 4; i < len; i++) { c = ngx_tolower(p[i]); if (c < '0' || (c > '9' && c < 'a' && c != '_') || c > 'z') { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "syslog \"tag\" only allows " "alphanumeric characters " "and underscore"); return NGX_CONF_ERROR; } } peer->tag.data = p + 4; peer->tag.len = len - 4; } else { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unknown syslog parameter \"%s\"", p); return NGX_CONF_ERROR; } next: if (comma == NULL) { break; } p = comma + 1; } return NGX_CONF_OK; } u_char * ngx_syslog_add_header(ngx_syslog_peer_t *peer, u_char *buf) { ngx_uint_t pri; pri = peer->facility * 8 + peer->severity; return ngx_sprintf(buf, "<%ui>%V %V %V: ", pri, &ngx_cached_syslog_time, &ngx_cycle->hostname, &peer->tag); } void ngx_syslog_writer(ngx_log_t *log, ngx_uint_t level, u_char *buf, size_t len) { u_char *p, msg[NGX_SYSLOG_MAX_STR]; ngx_uint_t head_len; ngx_syslog_peer_t *peer; peer = log->wdata; if (peer->busy) { return; } peer->busy = 1; peer->severity = level - 1; p = ngx_syslog_add_header(peer, msg); head_len = p - msg; len -= NGX_LINEFEED_SIZE; if (len > NGX_SYSLOG_MAX_STR - head_len) { len = NGX_SYSLOG_MAX_STR - head_len; } p = ngx_snprintf(p, len, "%s", buf); (void) ngx_syslog_send(peer, msg, p - msg); peer->busy = 0; } ssize_t ngx_syslog_send(ngx_syslog_peer_t *peer, u_char *buf, size_t len) { ssize_t n; if (peer->conn.fd == (ngx_socket_t) -1) { if (ngx_syslog_init_peer(peer) != NGX_OK) { return NGX_ERROR; } } /* log syslog socket events with valid log */ peer->conn.log = ngx_cycle->log; if (ngx_send) { n = ngx_send(&peer->conn, buf, len); } else { /* event module has not yet set ngx_io */ n = ngx_os_io.send(&peer->conn, buf, len); } #if (NGX_HAVE_UNIX_DOMAIN) if (n == NGX_ERROR && peer->server.sockaddr->sa_family == AF_UNIX) { if (ngx_close_socket(peer->conn.fd) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_close_socket_n " failed"); } peer->conn.fd = (ngx_socket_t) -1; } #endif return n; } static ngx_int_t ngx_syslog_init_peer(ngx_syslog_peer_t *peer) { ngx_socket_t fd; ngx_pool_cleanup_t *cln; peer->conn.read = &ngx_syslog_dummy_event; peer->conn.write = &ngx_syslog_dummy_event; ngx_syslog_dummy_event.log = &ngx_syslog_dummy_log; fd = ngx_socket(peer->server.sockaddr->sa_family, SOCK_DGRAM, 0); if (fd == (ngx_socket_t) -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_socket_n " failed"); return NGX_ERROR; } if (ngx_nonblocking(fd) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_nonblocking_n " failed"); goto failed; } if (connect(fd, peer->server.sockaddr, peer->server.socklen) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, "connect() failed"); goto failed; } cln = ngx_pool_cleanup_add(peer->pool, 0); if (cln == NULL) { goto failed; } cln->data = peer; cln->handler = ngx_syslog_cleanup; peer->conn.fd = fd; /* UDP sockets are always ready to write */ peer->conn.write->ready = 1; return NGX_OK; failed: if (ngx_close_socket(fd) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_close_socket_n " failed"); } return NGX_ERROR; } static void ngx_syslog_cleanup(void *data) { ngx_syslog_peer_t *peer = data; /* prevents further use of this peer */ peer->busy = 1; if (peer->conn.fd == (ngx_socket_t) -1) { return; } if (ngx_close_socket(peer->conn.fd) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_close_socket_n " failed"); } }