| /* |
| * Backend variables and functions. |
| * |
| * Copyright 2000-2006 Willy Tarreau <w@1wt.eu> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| * |
| */ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <syslog.h> |
| #include <string.h> |
| |
| #include <common/compat.h> |
| #include <common/config.h> |
| #include <common/time.h> |
| |
| #include <types/buffers.h> |
| #include <types/global.h> |
| #include <types/polling.h> |
| #include <types/proxy.h> |
| #include <types/server.h> |
| #include <types/session.h> |
| |
| #include <proto/backend.h> |
| #include <proto/fd.h> |
| #include <proto/httperr.h> |
| #include <proto/log.h> |
| #include <proto/proto_http.h> |
| #include <proto/queue.h> |
| #include <proto/stream_sock.h> |
| #include <proto/task.h> |
| |
| #ifdef CONFIG_HAP_CTTPROXY |
| #include <import/ip_tproxy.h> |
| #endif |
| |
| #ifdef CONFIG_HAP_TCPSPLICE |
| #include <libtcpsplice.h> |
| #endif |
| |
| /* |
| * This function recounts the number of usable active and backup servers for |
| * proxy <p>. These numbers are returned into the p->srv_act and p->srv_bck. |
| * This function also recomputes the total active and backup weights. |
| */ |
| void recount_servers(struct proxy *px) |
| { |
| struct server *srv; |
| |
| px->srv_act = 0; px->srv_bck = px->tot_wact = px->tot_wbck = 0; |
| for (srv = px->srv; srv != NULL; srv = srv->next) { |
| if (srv->state & SRV_RUNNING) { |
| if (srv->state & SRV_BACKUP) { |
| px->srv_bck++; |
| px->tot_wbck += srv->eweight + 1; |
| } else { |
| px->srv_act++; |
| px->tot_wact += srv->eweight + 1; |
| } |
| } |
| } |
| } |
| |
| /* This function recomputes the server map for proxy px. It |
| * relies on px->tot_wact and px->tot_wbck, so it must be |
| * called after recount_servers(). It also expects px->srv_map |
| * to be initialized to the largest value needed. |
| */ |
| void recalc_server_map(struct proxy *px) |
| { |
| int o, tot, flag; |
| struct server *cur, *best; |
| |
| if (px->srv_act) { |
| flag = SRV_RUNNING; |
| tot = px->tot_wact; |
| } else if (px->srv_bck) { |
| flag = SRV_RUNNING | SRV_BACKUP; |
| if (px->options & PR_O_USE_ALL_BK) |
| tot = px->tot_wbck; |
| else |
| tot = 1; /* the first server is enough */ |
| } else { |
| px->srv_map_sz = 0; |
| return; |
| } |
| |
| /* this algorithm gives priority to the first server, which means that |
| * it will respect the declaration order for equivalent weights, and |
| * that whatever the weights, the first server called will always be |
| * the first declard. This is an important asumption for the backup |
| * case, where we want the first server only. |
| */ |
| for (cur = px->srv; cur; cur = cur->next) |
| cur->wscore = 0; |
| |
| for (o = 0; o < tot; o++) { |
| int max = 0; |
| best = NULL; |
| for (cur = px->srv; cur; cur = cur->next) { |
| if ((cur->state & (SRV_RUNNING | SRV_BACKUP)) == flag) { |
| int v; |
| |
| /* If we are forced to return only one server, we don't want to |
| * go further, because we would return the wrong one due to |
| * divide overflow. |
| */ |
| if (tot == 1) { |
| best = cur; |
| break; |
| } |
| |
| cur->wscore += cur->eweight + 1; |
| v = (cur->wscore + tot) / tot; /* result between 0 and 3 */ |
| if (best == NULL || v > max) { |
| max = v; |
| best = cur; |
| } |
| } |
| } |
| px->srv_map[o] = best; |
| best->wscore -= tot; |
| } |
| px->srv_map_sz = tot; |
| } |
| |
| |
| /* |
| * This function marks the session as 'assigned' in direct or dispatch modes, |
| * or tries to assign one in balance mode, according to the algorithm. It does |
| * nothing if the session had already been assigned a server. |
| * |
| * It may return : |
| * SRV_STATUS_OK if everything is OK. s->srv will be valid. |
| * SRV_STATUS_NOSRV if no server is available. s->srv = NULL. |
| * SRV_STATUS_FULL if all servers are saturated. s->srv = NULL. |
| * SRV_STATUS_INTERNAL for other unrecoverable errors. |
| * |
| * Upon successful return, the session flag SN_ASSIGNED to indicate that it does |
| * not need to be called anymore. This usually means that s->srv can be trusted |
| * in balance and direct modes. This flag is not cleared, so it's to the caller |
| * to clear it if required (eg: redispatch). |
| * |
| */ |
| |
| int assign_server(struct session *s) |
| { |
| #ifdef DEBUG_FULL |
| fprintf(stderr,"assign_server : s=%p\n",s); |
| #endif |
| |
| if (s->pend_pos) |
| return SRV_STATUS_INTERNAL; |
| |
| if (!(s->flags & SN_ASSIGNED)) { |
| if ((s->be->beprm->options & PR_O_BALANCE) && !(s->flags & SN_DIRECT)) { |
| if (!s->be->beprm->srv_act && !s->be->beprm->srv_bck) |
| return SRV_STATUS_NOSRV; |
| |
| if (s->be->beprm->options & PR_O_BALANCE_RR) { |
| s->srv = get_server_rr_with_conns(s->be->beprm); |
| if (!s->srv) |
| return SRV_STATUS_FULL; |
| } |
| else if (s->be->beprm->options & PR_O_BALANCE_SH) { |
| int len; |
| |
| if (s->cli_addr.ss_family == AF_INET) |
| len = 4; |
| else if (s->cli_addr.ss_family == AF_INET6) |
| len = 16; |
| else /* unknown IP family */ |
| return SRV_STATUS_INTERNAL; |
| |
| s->srv = get_server_sh(s->be->beprm, |
| (void *)&((struct sockaddr_in *)&s->cli_addr)->sin_addr, |
| len); |
| } |
| else /* unknown balancing algorithm */ |
| return SRV_STATUS_INTERNAL; |
| } |
| s->flags |= SN_ASSIGNED; |
| } |
| return SRV_STATUS_OK; |
| } |
| |
| |
| /* |
| * This function assigns a server address to a session, and sets SN_ADDR_SET. |
| * The address is taken from the currently assigned server, or from the |
| * dispatch or transparent address. |
| * |
| * It may return : |
| * SRV_STATUS_OK if everything is OK. |
| * SRV_STATUS_INTERNAL for other unrecoverable errors. |
| * |
| * Upon successful return, the session flag SN_ADDR_SET is set. This flag is |
| * not cleared, so it's to the caller to clear it if required. |
| * |
| */ |
| int assign_server_address(struct session *s) |
| { |
| #ifdef DEBUG_FULL |
| fprintf(stderr,"assign_server_address : s=%p\n",s); |
| #endif |
| |
| if (s->flags & SN_DIRECT || s->be->beprm->options & PR_O_BALANCE) { |
| /* A server is necessarily known for this session */ |
| if (!(s->flags & SN_ASSIGNED)) |
| return SRV_STATUS_INTERNAL; |
| |
| s->srv_addr = s->srv->addr; |
| |
| /* if this server remaps proxied ports, we'll use |
| * the port the client connected to with an offset. */ |
| if (s->srv->state & SRV_MAPPORTS) { |
| struct sockaddr_in sockname; |
| socklen_t namelen = sizeof(sockname); |
| |
| if (!(s->fe->options & PR_O_TRANSP) || |
| get_original_dst(s->cli_fd, (struct sockaddr_in *)&sockname, &namelen) == -1) |
| getsockname(s->cli_fd, (struct sockaddr *)&sockname, &namelen); |
| s->srv_addr.sin_port = htons(ntohs(s->srv_addr.sin_port) + ntohs(sockname.sin_port)); |
| } |
| } |
| else if (*(int *)&s->be->beprm->dispatch_addr.sin_addr) { |
| /* connect to the defined dispatch addr */ |
| s->srv_addr = s->be->beprm->dispatch_addr; |
| } |
| else if (s->fe->options & PR_O_TRANSP) { |
| /* in transparent mode, use the original dest addr if no dispatch specified */ |
| socklen_t salen = sizeof(s->srv_addr); |
| |
| if (get_original_dst(s->cli_fd, &s->srv_addr, &salen) == -1) { |
| qfprintf(stderr, "Cannot get original server address.\n"); |
| return SRV_STATUS_INTERNAL; |
| } |
| } |
| |
| s->flags |= SN_ADDR_SET; |
| return SRV_STATUS_OK; |
| } |
| |
| |
| /* This function assigns a server to session <s> if required, and can add the |
| * connection to either the assigned server's queue or to the proxy's queue. |
| * |
| * Returns : |
| * |
| * SRV_STATUS_OK if everything is OK. |
| * SRV_STATUS_NOSRV if no server is available. s->srv = NULL. |
| * SRV_STATUS_QUEUED if the connection has been queued. |
| * SRV_STATUS_FULL if the server(s) is/are saturated and the |
| * connection could not be queued. |
| * SRV_STATUS_INTERNAL for other unrecoverable errors. |
| * |
| */ |
| int assign_server_and_queue(struct session *s) |
| { |
| struct pendconn *p; |
| int err; |
| |
| if (s->pend_pos) |
| return SRV_STATUS_INTERNAL; |
| |
| if (s->flags & SN_ASSIGNED) { |
| /* a server does not need to be assigned, perhaps because we're in |
| * direct mode, or in dispatch or transparent modes where the server |
| * is not needed. |
| */ |
| if (s->srv && |
| s->srv->maxconn && s->srv->cur_sess >= srv_dynamic_maxconn(s->srv)) { |
| p = pendconn_add(s); |
| if (p) |
| return SRV_STATUS_QUEUED; |
| else |
| return SRV_STATUS_FULL; |
| } |
| return SRV_STATUS_OK; |
| } |
| |
| /* a server needs to be assigned */ |
| err = assign_server(s); |
| switch (err) { |
| case SRV_STATUS_OK: |
| /* in balance mode, we might have servers with connection limits */ |
| if (s->srv && |
| s->srv->maxconn && s->srv->cur_sess >= srv_dynamic_maxconn(s->srv)) { |
| p = pendconn_add(s); |
| if (p) |
| return SRV_STATUS_QUEUED; |
| else |
| return SRV_STATUS_FULL; |
| } |
| return SRV_STATUS_OK; |
| |
| case SRV_STATUS_FULL: |
| /* queue this session into the proxy's queue */ |
| p = pendconn_add(s); |
| if (p) |
| return SRV_STATUS_QUEUED; |
| else |
| return SRV_STATUS_FULL; |
| |
| case SRV_STATUS_NOSRV: |
| case SRV_STATUS_INTERNAL: |
| return err; |
| default: |
| return SRV_STATUS_INTERNAL; |
| } |
| } |
| |
| |
| /* |
| * This function initiates a connection to the server assigned to this session |
| * (s->srv, s->srv_addr). It will assign a server if none is assigned yet. |
| * It can return one of : |
| * - SN_ERR_NONE if everything's OK |
| * - SN_ERR_SRVTO if there are no more servers |
| * - SN_ERR_SRVCL if the connection was refused by the server |
| * - SN_ERR_PRXCOND if the connection has been limited by the proxy (maxconn) |
| * - SN_ERR_RESOURCE if a system resource is lacking (eg: fd limits, ports, ...) |
| * - SN_ERR_INTERNAL for any other purely internal errors |
| * Additionnally, in the case of SN_ERR_RESOURCE, an emergency log will be emitted. |
| */ |
| int connect_server(struct session *s) |
| { |
| int fd, err; |
| |
| if (!(s->flags & SN_ADDR_SET)) { |
| err = assign_server_address(s); |
| if (err != SRV_STATUS_OK) |
| return SN_ERR_INTERNAL; |
| } |
| |
| if ((fd = s->srv_fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) == -1) { |
| qfprintf(stderr, "Cannot get a server socket.\n"); |
| |
| if (errno == ENFILE) |
| send_log(s->be->beprm, LOG_EMERG, |
| "Proxy %s reached system FD limit at %d. Please check system tunables.\n", |
| s->be->beprm->id, maxfd); |
| else if (errno == EMFILE) |
| send_log(s->be->beprm, LOG_EMERG, |
| "Proxy %s reached process FD limit at %d. Please check 'ulimit-n' and restart.\n", |
| s->be->beprm->id, maxfd); |
| else if (errno == ENOBUFS || errno == ENOMEM) |
| send_log(s->be->beprm, LOG_EMERG, |
| "Proxy %s reached system memory limit at %d sockets. Please check system tunables.\n", |
| s->be->beprm->id, maxfd); |
| /* this is a resource error */ |
| return SN_ERR_RESOURCE; |
| } |
| |
| if (fd >= global.maxsock) { |
| /* do not log anything there, it's a normal condition when this option |
| * is used to serialize connections to a server ! |
| */ |
| Alert("socket(): not enough free sockets. Raise -n argument. Giving up.\n"); |
| close(fd); |
| return SN_ERR_PRXCOND; /* it is a configuration limit */ |
| } |
| |
| #ifdef CONFIG_HAP_TCPSPLICE |
| if ((s->fe->options & s->be->beprm->options) & PR_O_TCPSPLICE) { |
| /* TCP splicing supported by both FE and BE */ |
| tcp_splice_initfd(s->cli_fd, fd); |
| } |
| #endif |
| |
| if ((fcntl(fd, F_SETFL, O_NONBLOCK)==-1) || |
| (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, (char *) &one, sizeof(one)) == -1)) { |
| qfprintf(stderr,"Cannot set client socket to non blocking mode.\n"); |
| close(fd); |
| return SN_ERR_INTERNAL; |
| } |
| |
| if (s->be->beprm->options & PR_O_TCP_SRV_KA) |
| setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (char *) &one, sizeof(one)); |
| |
| /* allow specific binding : |
| * - server-specific at first |
| * - proxy-specific next |
| */ |
| if (s->srv != NULL && s->srv->state & SRV_BIND_SRC) { |
| setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (char *) &one, sizeof(one)); |
| if (bind(fd, (struct sockaddr *)&s->srv->source_addr, sizeof(s->srv->source_addr)) == -1) { |
| Alert("Cannot bind to source address before connect() for server %s/%s. Aborting.\n", |
| s->be->beprm->id, s->srv->id); |
| close(fd); |
| send_log(s->be->beprm, LOG_EMERG, |
| "Cannot bind to source address before connect() for server %s/%s.\n", |
| s->be->beprm->id, s->srv->id); |
| return SN_ERR_RESOURCE; |
| } |
| #ifdef CONFIG_HAP_CTTPROXY |
| if (s->srv->state & SRV_TPROXY_MASK) { |
| struct in_tproxy itp1, itp2; |
| memset(&itp1, 0, sizeof(itp1)); |
| |
| itp1.op = TPROXY_ASSIGN; |
| switch (s->srv->state & SRV_TPROXY_MASK) { |
| case SRV_TPROXY_ADDR: |
| itp1.v.addr.faddr = s->srv->tproxy_addr.sin_addr; |
| itp1.v.addr.fport = s->srv->tproxy_addr.sin_port; |
| break; |
| case SRV_TPROXY_CLI: |
| itp1.v.addr.fport = ((struct sockaddr_in *)&s->cli_addr)->sin_port; |
| /* fall through */ |
| case SRV_TPROXY_CIP: |
| /* FIXME: what can we do if the client connects in IPv6 ? */ |
| itp1.v.addr.faddr = ((struct sockaddr_in *)&s->cli_addr)->sin_addr; |
| break; |
| } |
| |
| /* set connect flag on socket */ |
| itp2.op = TPROXY_FLAGS; |
| itp2.v.flags = ITP_CONNECT | ITP_ONCE; |
| |
| if (setsockopt(fd, SOL_IP, IP_TPROXY, &itp1, sizeof(itp1)) == -1 || |
| setsockopt(fd, SOL_IP, IP_TPROXY, &itp2, sizeof(itp2)) == -1) { |
| Alert("Cannot bind to tproxy source address before connect() for server %s/%s. Aborting.\n", |
| s->be->beprm->id, s->srv->id); |
| close(fd); |
| send_log(s->be->beprm, LOG_EMERG, |
| "Cannot bind to tproxy source address before connect() for server %s/%s.\n", |
| s->be->beprm->id, s->srv->id); |
| return SN_ERR_RESOURCE; |
| } |
| } |
| #endif |
| } |
| else if (s->be->beprm->options & PR_O_BIND_SRC) { |
| setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (char *) &one, sizeof(one)); |
| if (bind(fd, (struct sockaddr *)&s->be->beprm->source_addr, sizeof(s->be->beprm->source_addr)) == -1) { |
| Alert("Cannot bind to source address before connect() for proxy %s. Aborting.\n", s->be->beprm->id); |
| close(fd); |
| send_log(s->be->beprm, LOG_EMERG, |
| "Cannot bind to source address before connect() for server %s/%s.\n", |
| s->be->beprm->id, s->srv->id); |
| return SN_ERR_RESOURCE; |
| } |
| #ifdef CONFIG_HAP_CTTPROXY |
| if (s->be->beprm->options & PR_O_TPXY_MASK) { |
| struct in_tproxy itp1, itp2; |
| memset(&itp1, 0, sizeof(itp1)); |
| |
| itp1.op = TPROXY_ASSIGN; |
| switch (s->be->beprm->options & PR_O_TPXY_MASK) { |
| case PR_O_TPXY_ADDR: |
| itp1.v.addr.faddr = s->srv->tproxy_addr.sin_addr; |
| itp1.v.addr.fport = s->srv->tproxy_addr.sin_port; |
| break; |
| case PR_O_TPXY_CLI: |
| itp1.v.addr.fport = ((struct sockaddr_in *)&s->cli_addr)->sin_port; |
| /* fall through */ |
| case PR_O_TPXY_CIP: |
| /* FIXME: what can we do if the client connects in IPv6 ? */ |
| itp1.v.addr.faddr = ((struct sockaddr_in *)&s->cli_addr)->sin_addr; |
| break; |
| } |
| |
| /* set connect flag on socket */ |
| itp2.op = TPROXY_FLAGS; |
| itp2.v.flags = ITP_CONNECT | ITP_ONCE; |
| |
| if (setsockopt(fd, SOL_IP, IP_TPROXY, &itp1, sizeof(itp1)) == -1 || |
| setsockopt(fd, SOL_IP, IP_TPROXY, &itp2, sizeof(itp2)) == -1) { |
| Alert("Cannot bind to tproxy source address before connect() for proxy %s. Aborting.\n", |
| s->be->beprm->id); |
| close(fd); |
| send_log(s->be->beprm, LOG_EMERG, |
| "Cannot bind to tproxy source address before connect() for server %s/%s.\n", |
| s->be->beprm->id, s->srv->id); |
| return SN_ERR_RESOURCE; |
| } |
| } |
| #endif |
| } |
| |
| if ((connect(fd, (struct sockaddr *)&s->srv_addr, sizeof(s->srv_addr)) == -1) && |
| (errno != EINPROGRESS) && (errno != EALREADY) && (errno != EISCONN)) { |
| |
| if (errno == EAGAIN || errno == EADDRINUSE) { |
| char *msg; |
| if (errno == EAGAIN) /* no free ports left, try again later */ |
| msg = "no free ports"; |
| else |
| msg = "local address already in use"; |
| |
| qfprintf(stderr,"Cannot connect: %s.\n",msg); |
| close(fd); |
| send_log(s->be->beprm, LOG_EMERG, |
| "Connect() failed for server %s/%s: %s.\n", |
| s->be->beprm->id, s->srv->id, msg); |
| return SN_ERR_RESOURCE; |
| } else if (errno == ETIMEDOUT) { |
| //qfprintf(stderr,"Connect(): ETIMEDOUT"); |
| close(fd); |
| return SN_ERR_SRVTO; |
| } else { |
| // (errno == ECONNREFUSED || errno == ENETUNREACH || errno == EACCES || errno == EPERM) |
| //qfprintf(stderr,"Connect(): %d", errno); |
| close(fd); |
| return SN_ERR_SRVCL; |
| } |
| } |
| |
| fdtab[fd].owner = s->task; |
| fdtab[fd].state = FD_STCONN; /* connection in progress */ |
| fdtab[fd].cb[DIR_RD].f = &stream_sock_read; |
| fdtab[fd].cb[DIR_RD].b = s->rep; |
| fdtab[fd].cb[DIR_WR].f = &stream_sock_write; |
| fdtab[fd].cb[DIR_WR].b = s->req; |
| |
| MY_FD_SET(fd, StaticWriteEvent); /* for connect status */ |
| #if defined(DEBUG_FULL) && defined(ENABLE_EPOLL) |
| if (PrevReadEvent) { |
| assert(!(MY_FD_ISSET(fd, PrevReadEvent))); |
| assert(!(MY_FD_ISSET(fd, PrevWriteEvent))); |
| } |
| #endif |
| |
| fd_insert(fd); |
| if (s->srv) { |
| s->srv->cur_sess++; |
| if (s->srv->cur_sess > s->srv->cur_sess_max) |
| s->srv->cur_sess_max = s->srv->cur_sess; |
| } |
| |
| if (s->be->beprm->contimeout) |
| tv_delayfrom(&s->req->cex, &now, s->be->beprm->contimeout); |
| else |
| tv_eternity(&s->req->cex); |
| return SN_ERR_NONE; /* connection is OK */ |
| } |
| |
| |
| /* |
| * This function checks the retry count during the connect() job. |
| * It updates the session's srv_state and retries, so that the caller knows |
| * what it has to do. It uses the last connection error to set the log when |
| * it expires. It returns 1 when it has expired, and 0 otherwise. |
| */ |
| int srv_count_retry_down(struct session *t, int conn_err) |
| { |
| /* we are in front of a retryable error */ |
| t->conn_retries--; |
| if (t->conn_retries < 0) { |
| /* if not retryable anymore, let's abort */ |
| tv_eternity(&t->req->cex); |
| srv_close_with_err(t, conn_err, SN_FINST_C, |
| 503, error_message(t, HTTP_ERR_503)); |
| if (t->srv) |
| t->srv->failed_conns++; |
| t->be->beprm->failed_conns++; |
| |
| /* We used to have a free connection slot. Since we'll never use it, |
| * we have to inform the server that it may be used by another session. |
| */ |
| if (may_dequeue_tasks(t->srv, t->be->beprm)) |
| task_wakeup(&rq, t->srv->queue_mgt); |
| return 1; |
| } |
| return 0; |
| } |
| |
| |
| /* |
| * This function performs the retryable part of the connect() job. |
| * It updates the session's srv_state and retries, so that the caller knows |
| * what it has to do. It returns 1 when it breaks out of the loop, or 0 if |
| * it needs to redispatch. |
| */ |
| int srv_retryable_connect(struct session *t) |
| { |
| int conn_err; |
| |
| /* This loop ensures that we stop before the last retry in case of a |
| * redispatchable server. |
| */ |
| do { |
| /* initiate a connection to the server */ |
| conn_err = connect_server(t); |
| switch (conn_err) { |
| |
| case SN_ERR_NONE: |
| //fprintf(stderr,"0: c=%d, s=%d\n", c, s); |
| t->srv_state = SV_STCONN; |
| return 1; |
| |
| case SN_ERR_INTERNAL: |
| tv_eternity(&t->req->cex); |
| srv_close_with_err(t, SN_ERR_INTERNAL, SN_FINST_C, |
| 500, error_message(t, HTTP_ERR_500)); |
| if (t->srv) |
| t->srv->failed_conns++; |
| t->be->beprm->failed_conns++; |
| /* release other sessions waiting for this server */ |
| if (may_dequeue_tasks(t->srv, t->be->beprm)) |
| task_wakeup(&rq, t->srv->queue_mgt); |
| return 1; |
| } |
| /* ensure that we have enough retries left */ |
| if (srv_count_retry_down(t, conn_err)) { |
| return 1; |
| } |
| } while (t->srv == NULL || t->conn_retries > 0 || !(t->be->beprm->options & PR_O_REDISP)); |
| |
| /* We're on our last chance, and the REDISP option was specified. |
| * We will ignore cookie and force to balance or use the dispatcher. |
| */ |
| /* let's try to offer this slot to anybody */ |
| if (may_dequeue_tasks(t->srv, t->be->beprm)) |
| task_wakeup(&rq, t->srv->queue_mgt); |
| |
| if (t->srv) |
| t->srv->failed_conns++; |
| t->be->beprm->failed_conns++; |
| |
| t->flags &= ~(SN_DIRECT | SN_ASSIGNED | SN_ADDR_SET); |
| t->srv = NULL; /* it's left to the dispatcher to choose a server */ |
| if ((t->flags & SN_CK_MASK) == SN_CK_VALID) { |
| t->flags &= ~SN_CK_MASK; |
| t->flags |= SN_CK_DOWN; |
| } |
| return 0; |
| } |
| |
| |
| /* This function performs the "redispatch" part of a connection attempt. It |
| * will assign a server if required, queue the connection if required, and |
| * handle errors that might arise at this level. It can change the server |
| * state. It will return 1 if it encounters an error, switches the server |
| * state, or has to queue a connection. Otherwise, it will return 0 indicating |
| * that the connection is ready to use. |
| */ |
| |
| int srv_redispatch_connect(struct session *t) |
| { |
| int conn_err; |
| |
| /* We know that we don't have any connection pending, so we will |
| * try to get a new one, and wait in this state if it's queued |
| */ |
| conn_err = assign_server_and_queue(t); |
| switch (conn_err) { |
| case SRV_STATUS_OK: |
| break; |
| |
| case SRV_STATUS_NOSRV: |
| /* note: it is guaranteed that t->srv == NULL here */ |
| tv_eternity(&t->req->cex); |
| srv_close_with_err(t, SN_ERR_SRVTO, SN_FINST_C, |
| 503, error_message(t, HTTP_ERR_503)); |
| if (t->srv) |
| t->srv->failed_conns++; |
| t->be->beprm->failed_conns++; |
| |
| return 1; |
| |
| case SRV_STATUS_QUEUED: |
| /* FIXME-20060503 : we should use the queue timeout instead */ |
| if (t->be->beprm->contimeout) |
| tv_delayfrom(&t->req->cex, &now, t->be->beprm->contimeout); |
| else |
| tv_eternity(&t->req->cex); |
| t->srv_state = SV_STIDLE; |
| /* do nothing else and do not wake any other session up */ |
| return 1; |
| |
| case SRV_STATUS_FULL: |
| case SRV_STATUS_INTERNAL: |
| default: |
| tv_eternity(&t->req->cex); |
| srv_close_with_err(t, SN_ERR_INTERNAL, SN_FINST_C, |
| 500, error_message(t, HTTP_ERR_500)); |
| if (t->srv) |
| t->srv->failed_conns++; |
| t->be->beprm->failed_conns++; |
| |
| /* release other sessions waiting for this server */ |
| if (may_dequeue_tasks(t->srv, t->be->beprm)) |
| task_wakeup(&rq, t->srv->queue_mgt); |
| return 1; |
| } |
| /* if we get here, it's because we got SRV_STATUS_OK, which also |
| * means that the connection has not been queued. |
| */ |
| return 0; |
| } |
| |
| |
| /* |
| * Local variables: |
| * c-indent-level: 8 |
| * c-basic-offset: 8 |
| * End: |
| */ |