/* * disconnect and release a connection to the database */ void pool_discard_cp(char *user, char *database, int protoMajor) { POOL_CONNECTION_POOL *p = pool_get_cp(user, database, protoMajor, 0); ConnectionInfo *info; int i, freed = 0; if (p == NULL) { pool_error("pool_discard_cp: cannot get connection pool for user %s datbase %s", user, database); return; } for (i=0;i<NUM_BACKENDS;i++) { if (!VALID_BACKEND(i)) continue; if (!freed) { pool_free_startup_packet(CONNECTION_SLOT(p, i)->sp); freed = 1; } pool_close(CONNECTION(p, i)); free(CONNECTION_SLOT(p, i)); } info = p->info; memset(p, 0, sizeof(POOL_CONNECTION_POOL)); p->info = info; memset(p->info, 0, sizeof(ConnectionInfo) * MAX_NUM_BACKENDS); }
/* * find connection by user and database */ POOL_CONNECTION_POOL *pool_get_cp(char *user, char *database, int protoMajor, int check_socket) { #ifdef HAVE_SIGPROCMASK sigset_t oldmask; #else int oldmask; #endif int i; POOL_CONNECTION_POOL *p = pool_connection_pool; if (p == NULL) { pool_error("pool_get_cp: pool_connection_pool is not initialized"); return NULL; } POOL_SETMASK2(&BlockSig, &oldmask); for (i=0;i<pool_config.max_pool;i++) { if (MASTER_CONNECTION(p) && MASTER_CONNECTION(p)->sp->major == protoMajor && MASTER_CONNECTION(p)->sp->user != NULL && strcmp(MASTER_CONNECTION(p)->sp->user, user) == 0 && strcmp(MASTER_CONNECTION(p)->sp->database, database) == 0) { /* mark this connection is under use */ MASTER_CONNECTION(p)->closetime = 0; POOL_SETMASK(&oldmask); if (check_socket && (check_socket_status(MASTER(p)->fd) < 0 || (DUAL_MODE && check_socket_status(MASTER(p)->fd) < 0))) { pool_log("connection closed. retry to create new connection pool."); pool_free_startup_packet(MASTER_CONNECTION(p)->sp); pool_close(MASTER_CONNECTION(p)->con); free(MASTER_CONNECTION(p)); if (DUAL_MODE) { pool_close(SECONDARY_CONNECTION(p)->con); free(SECONDARY_CONNECTION(p)); } memset(p, 0, sizeof(POOL_CONNECTION_POOL)); return NULL; } return p; } p++; } POOL_SETMASK(&oldmask); return NULL; }
static POOL_CONNECTION_POOL *connect_backend(StartupPacket *sp, POOL_CONNECTION *frontend) { POOL_CONNECTION_POOL *backend; int i; /* connect to the backend */ backend = pool_create_cp(); if (backend == NULL) { pool_send_error_message(frontend, sp->major, "XX000", "connection cache is full", "", "increase max_pool", __FILE__, __LINE__); pool_close(frontend); pool_free_startup_packet(sp); return NULL; } for (i=0;i<NUM_BACKENDS;i++) { if (VALID_BACKEND(i)) { /* set DB node id */ CONNECTION(backend, i)->db_node_id = i; /* mark this is a backend connection */ CONNECTION(backend, i)->isbackend = 1; pool_ssl_negotiate_clientserver(CONNECTION(backend, i)); /* * save startup packet info */ CONNECTION_SLOT(backend, i)->sp = sp; /* send startup packet */ if (send_startup_packet(CONNECTION_SLOT(backend, i)) < 0) { pool_error("do_child: fails to send startup packet to the %d th backend", i); pool_discard_cp(sp->user, sp->database, sp->major); pool_close(frontend); return NULL; } } } /* * do authentication stuff */ if (pool_do_auth(frontend, backend)) { pool_close(frontend); pool_discard_cp(sp->user, sp->database, sp->major); return NULL; } return backend; }
/* * signal handler for SIGUSR1 * close all idle connections */ static RETSIGTYPE close_idle_connection(int sig) { int i, j; POOL_CONNECTION_POOL *p = pool_connection_pool; ConnectionInfo *info; pool_debug("child receives close connection request"); for (j=0;j<pool_config->max_pool;j++, p++) { if (!MASTER_CONNECTION(p)) continue; if (!MASTER_CONNECTION(p)->sp) continue; if (MASTER_CONNECTION(p)->sp->user == NULL) continue; if (MASTER_CONNECTION(p)->closetime > 0) /* idle connection? */ { pool_debug("close_idle_connection: close idle connection: user %s database %s", MASTER_CONNECTION(p)->sp->user, MASTER_CONNECTION(p)->sp->database); pool_send_frontend_exits(p); for (i=0;i<NUM_BACKENDS;i++) { if (!VALID_BACKEND(i)) continue; if (i == 0) { /* only first backend allocated the memory for the start up packet */ pool_free_startup_packet(CONNECTION_SLOT(p, i)->sp); } pool_close(CONNECTION(p, i)); } info = p->info; memset(p, 0, sizeof(POOL_CONNECTION_POOL)); p->info = info; memset(p->info, 0, sizeof(ConnectionInfo)); } } }
/* * disconnect and release a connection to the database */ void pool_discard_cp(char *user, char *database, int protoMajor) { POOL_CONNECTION_POOL *p = pool_get_cp(user, database, protoMajor, 0); if (p == NULL) { pool_error("pool_discard_cp: cannot get connection pool for user %s datbase %s", user, database); return; } pool_free_startup_packet(MASTER_CONNECTION(p)->sp); pool_close(MASTER_CONNECTION(p)->con); free(MASTER_CONNECTION(p)); if (DUAL_MODE) { /* do not free memory! we did not allocate them */ pool_close(SECONDARY_CONNECTION(p)->con); free(SECONDARY_CONNECTION(p)); } memset(p, 0, sizeof(POOL_CONNECTION_POOL)); }
/* * find connection by user and database */ POOL_CONNECTION_POOL *pool_get_cp(char *user, char *database, int protoMajor, int check_socket) { #ifdef HAVE_SIGPROCMASK sigset_t oldmask; #else int oldmask; #endif int i, freed = 0; ConnectionInfo *info; POOL_CONNECTION_POOL *p = pool_connection_pool; if (p == NULL) { pool_error("pool_get_cp: pool_connection_pool is not initialized"); return NULL; } POOL_SETMASK2(&BlockSig, &oldmask); for (i=0;i<pool_config->max_pool;i++) { if (MASTER_CONNECTION(p) && MASTER_CONNECTION(p)->sp && MASTER_CONNECTION(p)->sp->major == protoMajor && MASTER_CONNECTION(p)->sp->user != NULL && strcmp(MASTER_CONNECTION(p)->sp->user, user) == 0 && strcmp(MASTER_CONNECTION(p)->sp->database, database) == 0) { int sock_broken = 0; int j; /* mark this connection is under use */ MASTER_CONNECTION(p)->closetime = 0; for (j=0;j<NUM_BACKENDS;j++) { p->info[j].counter++; } POOL_SETMASK(&oldmask); if (check_socket) { for (j=0;j<NUM_BACKENDS;j++) { if (!VALID_BACKEND(j)) continue; if (CONNECTION_SLOT(p, j)) { sock_broken = check_socket_status(CONNECTION(p, j)->fd); if (sock_broken < 0) break; } else { sock_broken = -1; break; } } if (sock_broken < 0) { pool_log("connection closed. retry to create new connection pool."); for (j=0;j<NUM_BACKENDS;j++) { if (!VALID_BACKEND(j) || (CONNECTION_SLOT(p, j) == NULL)) continue; if (!freed) { pool_free_startup_packet(CONNECTION_SLOT(p, j)->sp); freed = 1; } pool_close(CONNECTION(p, j)); free(CONNECTION_SLOT(p, j)); } info = p->info; memset(p, 0, sizeof(POOL_CONNECTION_POOL_SLOT)); p->info = info; memset(p->info, 0, sizeof(ConnectionInfo) * MAX_NUM_BACKENDS); POOL_SETMASK(&oldmask); return NULL; } } POOL_SETMASK(&oldmask); pool_index = i; return p; } p++; } POOL_SETMASK(&oldmask); return NULL; }
void pool_backend_timer(void) { #define TMINTMAX 0x7fffffff POOL_CONNECTION_POOL *p = pool_connection_pool; int i, j; time_t now; time_t nearest = TMINTMAX; ConnectionInfo *info; POOL_SETMASK(&BlockSig); now = time(NULL); pool_debug("pool_backend_timer_handler called at %ld", now); for (i=0;i<pool_config->max_pool;i++, p++) { if (!MASTER_CONNECTION(p)) continue; if (!MASTER_CONNECTION(p)->sp) continue; if (MASTER_CONNECTION(p)->sp->user == NULL) continue; /* timer expire? */ if (MASTER_CONNECTION(p)->closetime) { int freed = 0; pool_debug("pool_backend_timer_handler: expire time: %ld", MASTER_CONNECTION(p)->closetime+pool_config->connection_life_time); if (now >= (MASTER_CONNECTION(p)->closetime+pool_config->connection_life_time)) { /* discard expired connection */ pool_debug("pool_backend_timer_handler: expires user %s database %s", MASTER_CONNECTION(p)->sp->user, MASTER_CONNECTION(p)->sp->database); pool_send_frontend_exits(p); for (j=0;j<NUM_BACKENDS;j++) { if (!VALID_BACKEND(j)) continue; if (!freed) { pool_free_startup_packet(CONNECTION_SLOT(p, j)->sp); freed = 1; } pool_close(CONNECTION(p, j)); free(CONNECTION_SLOT(p, j)); } info = p->info; memset(p, 0, sizeof(POOL_CONNECTION_POOL)); p->info = info; memset(p->info, 0, sizeof(ConnectionInfo) * MAX_NUM_BACKENDS); /* prepare to shutdown connections to system db */ if(pool_config->system_db_dynamic_connection && (pool_config->parallel_mode || pool_config->enable_query_cache)) { if (system_db_info->pgconn) pool_close_libpq_connection(); if (pool_system_db_connection() && pool_system_db_connection()->con) { pool_send_frontend_exit(pool_system_db_connection()->con); pool_close(pool_system_db_connection()->con); } if( system_db_info->connection ) { free( system_db_info->connection ); memset(system_db_info->connection, 0, sizeof(POOL_CONNECTION_POOL_SLOT)); system_db_info->connection = NULL; } } } else { /* look for nearest timer */ if (MASTER_CONNECTION(p)->closetime < nearest) nearest = MASTER_CONNECTION(p)->closetime; } } } /* any remaining timer */ if (nearest != TMINTMAX) { nearest = pool_config->connection_life_time - (now - nearest); if (nearest <= 0) nearest = 1; pool_signal(SIGALRM, pool_backend_timer_handler); alarm(nearest); } POOL_SETMASK(&UnBlockSig); }
/* * create a connection pool by user and database */ POOL_CONNECTION_POOL *pool_create_cp(void) { int i, freed = 0; time_t closetime; POOL_CONNECTION_POOL *oldestp; POOL_CONNECTION_POOL *ret; ConnectionInfo *info; POOL_CONNECTION_POOL *p = pool_connection_pool; if (p == NULL) { pool_error("pool_create_cp: pool_connection_pool is not initialized"); return NULL; } for (i=0;i<pool_config->max_pool;i++) { if (MASTER_CONNECTION(p) == NULL) { ret = new_connection(p); if (ret) pool_index = i; return ret; } p++; } pool_debug("no empty connection slot was found"); /* * no empty connection slot was found. look for the oldest connection and discard it. */ oldestp = p = pool_connection_pool; closetime = MASTER_CONNECTION(p)->closetime; pool_index = 0; for (i=0;i<pool_config->max_pool;i++) { pool_debug("user: %s database: %s closetime: %ld", MASTER_CONNECTION(p)->sp->user, MASTER_CONNECTION(p)->sp->database, MASTER_CONNECTION(p)->closetime); if (MASTER_CONNECTION(p)->closetime < closetime) { closetime = MASTER_CONNECTION(p)->closetime; oldestp = p; pool_index = i; } p++; } p = oldestp; pool_send_frontend_exits(p); pool_debug("discarding old %zd th connection. user: %s database: %s", oldestp - pool_connection_pool, MASTER_CONNECTION(p)->sp->user, MASTER_CONNECTION(p)->sp->database); for (i=0;i<NUM_BACKENDS;i++) { if (!VALID_BACKEND(i)) continue; if (!freed) { pool_free_startup_packet(CONNECTION_SLOT(p, i)->sp); freed = 1; } pool_close(CONNECTION(p, i)); free(CONNECTION_SLOT(p, i)); } info = p->info; memset(p, 0, sizeof(POOL_CONNECTION_POOL)); p->info = info; memset(p->info, 0, sizeof(ConnectionInfo) * MAX_NUM_BACKENDS); ret = new_connection(p); return ret; }
/* * child main loop */ void do_child(int unix_fd, int inet_fd) { POOL_CONNECTION *frontend; POOL_CONNECTION_POOL *backend; struct timeval now; struct timezone tz; struct timeval timeout; static int connected; /* non 0 if has been accepted connections from frontend */ int connections_count = 0; /* used if child_max_connections > 0 */ int found; char psbuf[NI_MAXHOST + 128]; pool_debug("I am %d", getpid()); /* Identify myself via ps */ init_ps_display("", "", "", ""); /* set up signal handlers */ signal(SIGALRM, SIG_DFL); signal(SIGTERM, die); signal(SIGINT, die); signal(SIGHUP, reload_config_handler); signal(SIGQUIT, die); signal(SIGCHLD, SIG_DFL); signal(SIGUSR1, close_idle_connection); signal(SIGUSR2, wakeup_handler); signal(SIGPIPE, SIG_IGN); #ifdef NONE_BLOCK /* set listen fds to none-blocking */ pool_set_nonblock(unix_fd); if (inet_fd) { pool_set_nonblock(inet_fd); } #endif /* Initialize my backend status */ pool_initialize_private_backend_status(); /* Initialize per process context */ pool_init_process_context(); /* initialize random seed */ gettimeofday(&now, &tz); #if defined(sun) || defined(__sun) srand((unsigned int) now.tv_usec); #else srandom((unsigned int) now.tv_usec); #endif /* initialize system db connection */ init_system_db_connection(); /* initialize connection pool */ if (pool_init_cp()) { child_exit(1); } /* * Open pool_passwd in child process. This is necessary to avoid the * file descriptor race condition reported in [pgpool-general: 1141]. */ if (strcmp("", pool_config->pool_passwd)) { pool_reopen_passwd_file(); } timeout.tv_sec = pool_config->child_life_time; timeout.tv_usec = 0; for (;;) { StartupPacket *sp; idle = 1; /* pgpool stop request already sent? */ check_stop_request(); /* Check if restart request is set because of failback event * happend. If so, exit myself with exit code 1 to be * restarted by pgpool parent. */ if (pool_get_my_process_info()->need_to_restart) { pool_log("do_child: failback event found. restart myself."); pool_get_my_process_info()->need_to_restart = 0; child_exit(1); } accepted = 0; /* perform accept() */ frontend = do_accept(unix_fd, inet_fd, &timeout); if (frontend == NULL) /* connection request from frontend timed out */ { /* check select() timeout */ if (connected && pool_config->child_life_time > 0 && timeout.tv_sec == 0 && timeout.tv_usec == 0) { pool_debug("child life %d seconds expired", pool_config->child_life_time); /* * Doesn't need to call this. child_exit() calls it. * send_frontend_exits(); */ child_exit(2); } continue; } /* set frontend fd to blocking */ pool_unset_nonblock(frontend->fd); /* reset busy flag */ idle = 0; /* check backend timer is expired */ if (backend_timer_expired) { pool_backend_timer(); backend_timer_expired = 0; } /* read the startup packet */ retry_startup: sp = read_startup_packet(frontend); if (sp == NULL) { /* failed to read the startup packet. return to the accept() loop */ pool_close(frontend); connection_count_down(); continue; } /* cancel request? */ if (sp->major == 1234 && sp->minor == 5678) { cancel_request((CancelPacket *)sp->startup_packet); pool_close(frontend); pool_free_startup_packet(sp); connection_count_down(); continue; } /* SSL? */ if (sp->major == 1234 && sp->minor == 5679 && !frontend->ssl_active) { pool_debug("SSLRequest from client"); pool_ssl_negotiate_serverclient(frontend); goto retry_startup; } if (pool_config->enable_pool_hba) { /* * do client authentication. * Note that ClientAuthentication does not return if frontend * was rejected; it simply terminates this process. */ frontend->protoVersion = sp->major; frontend->database = strdup(sp->database); if (frontend->database == NULL) { pool_error("do_child: strdup failed: %s\n", strerror(errno)); child_exit(1); } frontend->username = strdup(sp->user); if (frontend->username == NULL) { pool_error("do_child: strdup failed: %s\n", strerror(errno)); child_exit(1); } ClientAuthentication(frontend); } /* * Ok, negotiation with frontend has been done. Let's go to the * next step. Connect to backend if there's no existing * connection which can be reused by this frontend. * Authentication is also done in this step. */ /* Check if restart request is set because of failback event * happend. If so, close idle connections to backend and make * a new copy of backend status. */ if (pool_get_my_process_info()->need_to_restart) { pool_log("do_child: failback event found. discard existing connections"); pool_get_my_process_info()->need_to_restart = 0; close_idle_connection(0); pool_initialize_private_backend_status(); } /* * if there's no connection associated with user and database, * we need to connect to the backend and send the startup packet. */ /* look for existing connection */ found = 0; backend = pool_get_cp(sp->user, sp->database, sp->major, 1); if (backend != NULL) { found = 1; /* existing connection associated with same user/database/major found. * however we should make sure that the startup packet contents are identical. * OPTION data and others might be different. */ if (sp->len != MASTER_CONNECTION(backend)->sp->len) { pool_debug("do_child: connection exists but startup packet length is not identical"); found = 0; } else if(memcmp(sp->startup_packet, MASTER_CONNECTION(backend)->sp->startup_packet, sp->len) != 0) { pool_debug("do_child: connection exists but startup packet contents is not identical"); found = 0; } if (found == 0) { /* we need to discard existing connection since startup packet is different */ pool_discard_cp(sp->user, sp->database, sp->major); backend = NULL; } } if (backend == NULL) { /* create a new connection to backend */ if ((backend = connect_backend(sp, frontend)) == NULL) { connection_count_down(); continue; } } else { /* reuse existing connection */ if (!connect_using_existing_connection(frontend, backend, sp)) continue; } connected = 1; /* show ps status */ sp = MASTER_CONNECTION(backend)->sp; snprintf(psbuf, sizeof(psbuf), "%s %s %s idle", sp->user, sp->database, remote_ps_data); set_ps_display(psbuf, false); /* * Initialize per session context */ pool_init_session_context(frontend, backend); /* Mark this connection pool is connected from frontend */ pool_coninfo_set_frontend_connected(pool_get_process_context()->proc_id, pool_pool_index()); /* query process loop */ for (;;) { POOL_STATUS status; status = pool_process_query(frontend, backend, 0); sp = MASTER_CONNECTION(backend)->sp; switch (status) { /* client exits */ case POOL_END: /* * do not cache connection if: * pool_config->connection_cahe == 0 or * database name is template0, template1, postgres or regression */ if (pool_config->connection_cache == 0 || !strcmp(sp->database, "template0") || !strcmp(sp->database, "template1") || !strcmp(sp->database, "postgres") || !strcmp(sp->database, "regression")) { reset_connection(); pool_close(frontend); pool_send_frontend_exits(backend); pool_discard_cp(sp->user, sp->database, sp->major); } else { POOL_STATUS status1; /* send reset request to backend */ status1 = pool_process_query(frontend, backend, 1); pool_close(frontend); /* if we detect errors on resetting connection, we need to discard * this connection since it might be in unknown status */ if (status1 != POOL_CONTINUE) { pool_debug("error in resetting connections. discarding connection pools..."); pool_send_frontend_exits(backend); pool_discard_cp(sp->user, sp->database, sp->major); } else pool_connection_pool_timer(backend); } break; /* error occurred. discard backend connection pool and disconnect connection to the frontend */ case POOL_ERROR: pool_log("do_child: exits with status 1 due to error"); child_exit(1); break; /* fatal error occurred. just exit myself... */ case POOL_FATAL: notice_backend_error(1); child_exit(1); break; /* not implemented yet */ case POOL_IDLE: do_accept(unix_fd, inet_fd, &timeout); pool_debug("accept while idle"); break; default: break; } if (status != POOL_CONTINUE) break; } /* Destroy session context */ pool_session_context_destroy(); /* Mark this connection pool is not connected from frontend */ pool_coninfo_unset_frontend_connected(pool_get_process_context()->proc_id, pool_pool_index()); accepted = 0; connection_count_down(); timeout.tv_sec = pool_config->child_life_time; timeout.tv_usec = 0; /* increment queries counter if necessary */ if ( pool_config->child_max_connections > 0 ) connections_count++; /* check if maximum connections count for this child reached */ if ( ( pool_config->child_max_connections > 0 ) && ( connections_count >= pool_config->child_max_connections ) ) { pool_log("child exiting, %d connections reached", pool_config->child_max_connections); send_frontend_exits(); child_exit(2); } } child_exit(0); }
/* * Read startup packet * * Read the startup packet and parse the contents. */ static StartupPacket *read_startup_packet(POOL_CONNECTION *cp) { StartupPacket *sp; StartupPacket_v2 *sp2; int protov; int len; char *p; sp = (StartupPacket *)calloc(sizeof(*sp), 1); if (!sp) { pool_error("read_startup_packet: out of memory"); return NULL; } if (pool_config->authentication_timeout > 0) { pool_signal(SIGALRM, authentication_timeout); alarm(pool_config->authentication_timeout); } /* read startup packet length */ if (pool_read(cp, &len, sizeof(len))) { pool_error("read_startup_packet: incorrect packet length (%d)", len); pool_free_startup_packet(sp); alarm(0); pool_signal(SIGALRM, SIG_IGN); return NULL; } len = ntohl(len); len -= sizeof(len); if (len <= 0 || len >= MAX_STARTUP_PACKET_LENGTH) { pool_error("read_startup_packet: incorrect packet length (%d)", len); pool_free_startup_packet(sp); alarm(0); pool_signal(SIGALRM, SIG_IGN); return NULL; } sp->startup_packet = calloc(len, 1); if (!sp->startup_packet) { pool_error("read_startup_packet: out of memory"); pool_free_startup_packet(sp); alarm(0); pool_signal(SIGALRM, SIG_IGN); return NULL; } /* read startup packet */ if (pool_read(cp, sp->startup_packet, len)) { pool_free_startup_packet(sp); alarm(0); pool_signal(SIGALRM, SIG_IGN); return NULL; } sp->len = len; memcpy(&protov, sp->startup_packet, sizeof(protov)); sp->major = ntohl(protov)>>16; sp->minor = ntohl(protov) & 0x0000ffff; p = sp->startup_packet; switch(sp->major) { case PROTO_MAJOR_V2: /* V2 */ sp2 = (StartupPacket_v2 *)(sp->startup_packet); sp->database = calloc(SM_DATABASE+1, 1); if (!sp->database) { pool_error("read_startup_packet: out of memory"); pool_free_startup_packet(sp); alarm(0); pool_signal(SIGALRM, SIG_IGN); return NULL; } strncpy(sp->database, sp2->database, SM_DATABASE); sp->user = calloc(SM_USER+1, 1); if (!sp->user) { pool_error("read_startup_packet: out of memory"); pool_free_startup_packet(sp); alarm(0); pool_signal(SIGALRM, SIG_IGN); return NULL; } strncpy(sp->user, sp2->user, SM_USER); break; case PROTO_MAJOR_V3: /* V3 */ p += sizeof(int); /* skip protocol version info */ while(*p) { if (!strcmp("user", p)) { p += (strlen(p) + 1); sp->user = strdup(p); if (!sp->user) { pool_error("read_startup_packet: out of memory"); pool_free_startup_packet(sp); alarm(0); pool_signal(SIGALRM, SIG_IGN); return NULL; } } else if (!strcmp("database", p)) { p += (strlen(p) + 1); sp->database = strdup(p); if (!sp->database) { pool_error("read_startup_packet: out of memory"); pool_free_startup_packet(sp); alarm(0); pool_signal(SIGALRM, SIG_IGN); return NULL; } } /* * From 9.0, the start up packet may include * application name. After receiving such that packet, * backend sends parameter status of application_name. * Upon reusing connection to backend, we need to * emulate this behavior of backend. So we remember * this and send parameter status packet to frontend * instead of backend in * connect_using_existing_connection(). */ else if (!strcmp("application_name", p)) { p += (strlen(p) + 1); sp->application_name = p; pool_debug("read_startup_packet: application_name: %s", p); } p += (strlen(p) + 1); } break; case 1234: /* cancel or SSL request */ /* set dummy database, user info */ sp->database = calloc(1, 1); if (!sp->database) { pool_error("read_startup_packet: out of memory"); pool_free_startup_packet(sp); alarm(0); pool_signal(SIGALRM, SIG_IGN); return NULL; } sp->user = calloc(1, 1); if (!sp->user) { pool_error("read_startup_packet: out of memory"); pool_free_startup_packet(sp); alarm(0); pool_signal(SIGALRM, SIG_IGN); return NULL; } break; default: pool_error("read_startup_packet: invalid major no: %d", sp->major); pool_free_startup_packet(sp); alarm(0); pool_signal(SIGALRM, SIG_IGN); return NULL; } pool_debug("Protocol Major: %d Minor: %d database: %s user: %s", sp->major, sp->minor, sp->database, sp->user); alarm(0); pool_signal(SIGALRM, SIG_IGN); return sp; }
/* * Reuse existing connection */ static bool connect_using_existing_connection(POOL_CONNECTION *frontend, POOL_CONNECTION_POOL *backend, StartupPacket *sp) { int i, freed = 0; /* * Save startup packet info */ for (i = 0; i < NUM_BACKENDS; i++) { if (VALID_BACKEND(i)) { if (!freed) { pool_free_startup_packet(backend->slots[i]->sp); freed = 1; } backend->slots[i]->sp = sp; } } /* Reuse existing connection to backend */ if (pool_do_reauth(frontend, backend)) { pool_close(frontend); connection_count_down(); return false; } if (MAJOR(backend) == 3) { char command_buf[1024]; /* If we have received application_name in the start up * packet, we send SET command to backend. Also we add or * replace existing application_name data. */ if (sp->application_name) { snprintf(command_buf, sizeof(command_buf), "SET application_name TO '%s'", sp->application_name); for (i=0;i<NUM_BACKENDS;i++) { if (VALID_BACKEND(i)) if (do_command(frontend, CONNECTION(backend, i), command_buf, MAJOR(backend), MASTER_CONNECTION(backend)->pid, MASTER_CONNECTION(backend)->key, 0) != POOL_CONTINUE) { pool_error("connect_using_existing_connection: do_command failed. command: %s", command_buf); return false; } } pool_add_param(&MASTER(backend)->params, "application_name", sp->application_name); } if (send_params(frontend, backend)) { pool_close(frontend); connection_count_down(); return false; } } /* Send ReadyForQuery to frontend */ pool_write(frontend, "Z", 1); if (MAJOR(backend) == 3) { int len; char tstate; len = htonl(5); pool_write(frontend, &len, sizeof(len)); tstate = TSTATE(backend, MASTER_NODE_ID); pool_write(frontend, &tstate, 1); } if (pool_flush(frontend) < 0) { pool_close(frontend); connection_count_down(); return false; } return true; }
void pool_backend_timer(void) { #define TMINTMAX 0x7fffffff POOL_CONNECTION_POOL *p = pool_connection_pool; int i; time_t now; time_t nearest = TMINTMAX; POOL_SETMASK(&BlockSig); now = time(NULL); pool_debug("pool_backend_timer_handler called at %d", now); for (i=0;i<pool_config.max_pool;i++, p++) { if (!MASTER_CONNECTION(p)) continue; if (MASTER_CONNECTION(p)->sp->user == NULL) continue; /* timer expire? */ if (MASTER_CONNECTION(p)->closetime) { pool_debug("pool_backend_timer_handler: expire time: %d", MASTER_CONNECTION(p)->closetime+pool_config.connection_life_time); if (now >= (MASTER_CONNECTION(p)->closetime+pool_config.connection_life_time)) { /* discard expired connection */ pool_debug("pool_backend_timer_handler: expires user %s database %s", MASTER_CONNECTION(p)->sp->user, MASTER_CONNECTION(p)->sp->database); pool_send_frontend_exits(p); pool_free_startup_packet(MASTER_CONNECTION(p)->sp); pool_close(MASTER_CONNECTION(p)->con); free(MASTER_CONNECTION(p)); if (DUAL_MODE) { pool_close(SECONDARY_CONNECTION(p)->con); free(SECONDARY_CONNECTION(p)); } memset(p, 0, sizeof(POOL_CONNECTION_POOL)); } else { /* look for nearest timer */ if (MASTER_CONNECTION(p)->closetime < nearest) nearest = MASTER_CONNECTION(p)->closetime; } } } /* any remaining timer */ if (nearest != TMINTMAX) { nearest = pool_config.connection_life_time - (now - nearest); if (nearest <= 0) nearest = 1; pool_signal(SIGALRM, pool_backend_timer_handler); alarm(nearest); } POOL_SETMASK(&UnBlockSig); }
/* * create a connection pool by user and database */ POOL_CONNECTION_POOL *pool_create_cp(void) { int i; time_t closetime; POOL_CONNECTION_POOL *oldestp; POOL_CONNECTION_POOL *p = pool_connection_pool; if (p == NULL) { pool_error("pool_create_cp: pool_connection_pool is not initialized"); return NULL; } for (i=0;i<pool_config.max_pool;i++) { if (MASTER_CONNECTION(p) == NULL) return new_connection(p); p++; } pool_debug("no empty connection slot was found"); /* * no empty connection slot was found. look for the oldest connection and discard it. */ oldestp = p = pool_connection_pool; closetime = MASTER_CONNECTION(p)->closetime; for (i=0;i<pool_config.max_pool;i++) { pool_debug("user: %s database: %s closetime: %d", MASTER_CONNECTION(p)->sp->user, MASTER_CONNECTION(p)->sp->database, MASTER_CONNECTION(p)->closetime); if (MASTER_CONNECTION(p)->closetime < closetime) { closetime = MASTER_CONNECTION(p)->closetime; oldestp = p; } p++; } p = oldestp; pool_send_frontend_exits(p); pool_debug("discarding old %d th connection. user: %s database: %s", oldestp - pool_connection_pool, MASTER_CONNECTION(p)->sp->user, MASTER_CONNECTION(p)->sp->database); pool_free_startup_packet(MASTER_CONNECTION(p)->sp); pool_close(MASTER_CONNECTION(p)->con); free(MASTER_CONNECTION(p)); if (DUAL_MODE) { /* do not free memory! we did not allocate them */ pool_close(SECONDARY_CONNECTION(p)->con); free(SECONDARY_CONNECTION(p)); } memset(p, 0, sizeof(POOL_CONNECTION_POOL)); return new_connection(p); }