/* notice backend connection error using SIGUSR1 */
void degenerate_backend_set(int *node_id_set, int count)
{
pid_t parent = getppid();
int i;
if (pool_config->parallel_mode)
{
return;
}
pool_semaphore_lock(REQUEST_INFO_SEM);
Req_info->kind = NODE_DOWN_REQUEST;
for (i = 0; i < count; i++)
{
if (node_id_set[i] < 0 || node_id_set[i] >= MAX_NUM_BACKENDS ||
!VALID_BACKEND(node_id_set[i]))
{
pool_log("notice_backend_error: node %d is not valid backend.", i);
continue;
}
pool_log("notice_backend_error: %d fail over request from pid %d", node_id_set[i], getpid());
Req_info->node_id[i] = node_id_set[i];
}
kill(parent, SIGUSR1);
pool_semaphore_unlock(REQUEST_INFO_SEM);
}
/* handle other pgpool's down */
static int
pgpool_down(WdInfo * pool)
{
int rtn = WD_OK;
WD_STATUS prev_status;
pool_log("pgpool_down: %s:%d is going down",
pool->hostname, pool->pgpool_port);
prev_status = pool->status;
pool->status = WD_DOWN;
/* the active pgpool goes down and I'm sandby pgpool */
if (prev_status == WD_MASTER && WD_MYSELF->status == WD_NORMAL)
{
if (wd_am_I_oldest() == WD_OK)
{
pool_log("pgpool_down: I'm oldest so standing for master");
/* stand for master */
rtn = wd_stand_for_master();
if (rtn == WD_OK)
{
/* win */
wd_escalation();
}
else
{
/* rejected by others */
pool->status = prev_status;
}
}
}
return rtn;
}
static RETSIGTYPE exit_handler(int sig)
{
int i;
POOL_SETMASK(&AuthBlockSig);
/*
* this could happen in a child process if a signal has been sent
* before resetting signal handler
*/
if (getpid() != mypid)
{
pool_debug("exit_handler: I am not parent");
POOL_SETMASK(&UnBlockSig);
pool_shmem_exit(0);
exit(0);
}
if (sig == SIGTERM)
pool_log("received smart shutdown request");
else if (sig == SIGINT)
pool_log("received fast shutdown request");
else if (sig == SIGQUIT)
pool_log("received immediate shutdown request");
else
{
pool_error("exit_handler: unknown signal received %d", sig);
POOL_SETMASK(&UnBlockSig);
return;
}
exiting = 1;
for (i = 0; i < pool_config->num_init_children; i++)
{
pid_t pid = pids[i].pid;
if (pid)
{
kill(pid, sig);
}
}
kill(pcp_pid, sig);
POOL_SETMASK(&UnBlockSig);
while (wait(NULL) > 0)
;
if (errno != ECHILD)
pool_error("wait() failed. reason:%s", strerror(errno));
pids = NULL;
myexit(0);
}
/*
* Read the status file
*/
static int read_status_file(void)
{
FILE *fd;
char fnamebuf[POOLMAXPATHLEN];
int i;
snprintf(fnamebuf, sizeof(fnamebuf), "%s/%s", pool_config->logdir, STATUS_FILE_NAME);
fd = fopen(fnamebuf, "r");
if (!fd)
{
pool_log("Backend status file %s does not exist", fnamebuf);
return -1;
}
if (fread(&backend_rec, 1, sizeof(backend_rec), fd) <= 0)
{
pool_error("Could not read backend status file as %s. reason: %s",
fnamebuf, strerror(errno));
fclose(fd);
return -1;
}
fclose(fd);
for (i=0;i< pool_config->backend_desc->num_backends;i++)
{
if (backend_rec.status[i] == CON_DOWN)
BACKEND_INFO(i).backend_status = CON_DOWN;
else
BACKEND_INFO(i).backend_status = CON_CONNECT_WAIT;
}
return 0;
}
/*
* Do house keeping works when pgpool child process exits
*/
void child_exit(int code)
{
if (getpid() == mypid)
{
pool_log("child_exit: called from pgpool main. ignored.");
return;
}
/* count down global connection counter */
if (accepted)
connection_count_down();
/* prepare to shutdown connections to system db */
if(pool_config->parallel_mode || pool_config->enable_query_cache)
{
if (system_db_info->pgconn)
pool_close_libpq_connection();
if (pool_system_db_connection())
pool_close(pool_system_db_connection()->con);
}
if (pool_config->memory_cache_enabled && !pool_is_shmem_cache())
{
memcached_disconnect();
}
/* let backend know now we are exiting */
if (pool_connection_pool)
send_frontend_exits();
exit(code);
}
/*
* 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 void reload_config(void)
{
pool_log("reload config files.");
pool_get_config(get_config_file_name(), RELOAD_CONFIG);
if (pool_config->enable_pool_hba)
load_hba(get_hba_file_name());
reload_config_request = 0;
}
static void reload_config(void)
{
pool_log("reload config files.");
pool_get_config(conf_file, RELOAD_CONFIG);
if (pool_config->enable_pool_hba)
load_hba(hba_file);
if (pool_config->parallel_mode)
pool_memset_system_db_info(system_db_info->info);
kill_all_children(SIGHUP);
}
int
wd_escalation(void)
{
int rtn;
pool_log("wd_escalation: escalating to master pgpool");
/* clear shared memory cache */
if (pool_config->memory_cache_enabled && pool_is_shmem_cache() &&
pool_config->clear_memqcache_on_escalation)
{
pool_log("wd_escalation: clear all the query cache on shared memory");
pool_clear_memory_cache();
}
/* execute escalation command */
if (strlen(pool_config->wd_escalation_command))
{
system(pool_config->wd_escalation_command);
}
/* interface up as delegate IP */
if (strlen(pool_config->delegate_IP) != 0)
wd_IP_up();
/* set master status to the wd list */
wd_set_wd_list(pool_config->wd_hostname, pool_config->port,
pool_config->wd_port, pool_config->delegate_IP,
NULL, WD_MASTER);
/* send declare packet */
rtn = wd_declare();
if (rtn == WD_OK)
{
pool_log("wd_escalation: escalated to master pgpool successfully");
}
return rtn;
}
/* fork lifecheck process*/
static pid_t
fork_a_lifecheck(int fork_wait_time)
{
pid_t pid;
pid = fork();
if (pid != 0)
{
if (pid == -1)
pool_error("fork_a_lifecheck: fork() failed.");
return pid;
}
if (fork_wait_time > 0) {
sleep(fork_wait_time);
}
myargv = save_ps_display_args(myargc, myargv);
POOL_SETMASK(&UnBlockSig);
init_ps_display("", "", "", "");
signal(SIGTERM, wd_exit);
signal(SIGINT, wd_exit);
signal(SIGQUIT, wd_exit);
signal(SIGCHLD, SIG_DFL);
signal(SIGHUP, SIG_IGN);
signal(SIGPIPE, SIG_IGN);
set_ps_display("lifecheck",false);
/* wait until ready to go */
while (WD_OK != is_wd_lifecheck_ready())
{
sleep(pool_config->wd_interval * 10);
}
pool_log("watchdog: lifecheck started");
/* watchdog loop */
for (;;)
{
/* pgpool life check */
wd_lifecheck();
sleep(pool_config->wd_interval);
}
return pid;
}
int
wd_chk_setuid(void)
{
char path[128];
char cmd[128];
/* check setuid bit of ifup command */
wd_get_cmd(cmd, pool_config->if_up_cmd);
snprintf(path, sizeof(path), "%s/%s", pool_config->ifconfig_path, cmd);
if (! has_setuid_bit(path))
{
pool_log("wd_chk_setuid: ifup[%s] doesn't have setuid bit", path);
return 0;
}
/* check setuid bit of ifdown command */
wd_get_cmd(cmd, pool_config->if_down_cmd);
snprintf(path, sizeof(path), "%s/%s", pool_config->ifconfig_path, cmd);
if (! has_setuid_bit(path))
{
pool_log("wd_chk_setuid: ifdown[%s] doesn't have setuid bit", path);
return 0;
}
/* check setuid bit of arping command */
wd_get_cmd(cmd, pool_config->arping_cmd);
snprintf(path, sizeof(path), "%s/%s", pool_config->arping_path, cmd);
if (! has_setuid_bit(path))
{
pool_log("wd_chk_setuid: arping[%s] doesn't have setuid bit", path);
return 0;
}
pool_log("wd_chk_setuid all commands have setuid bit");
return 1;
}
/* send failback request using SIGUSR1 */
void send_failback_request(int node_id)
{
pid_t parent = getppid();
pool_log("send_failback_request: fail back %d th node request from pid %d", node_id, getpid());
Req_info->kind = NODE_UP_REQUEST;
Req_info->node_id[0] = node_id;
if (node_id < 0 || node_id >= MAX_NUM_BACKENDS || VALID_BACKEND(node_id))
{
pool_error("send_failback_request: node %d is alive.", node_id);
return;
}
kill(parent, SIGUSR1);
}
/*
* Read the status file
*/
static int read_status_file(void)
{
FILE *fd;
char fnamebuf[POOLMAXPATHLEN];
int i;
bool someone_wakeup = false;
snprintf(fnamebuf, sizeof(fnamebuf), "%s/%s", pool_config->logdir, STATUS_FILE_NAME);
fd = fopen(fnamebuf, "r");
if (!fd)
{
pool_log("Backend status file %s does not exist", fnamebuf);
return -1;
}
if (fread(&backend_rec, 1, sizeof(backend_rec), fd) != sizeof(backend_rec))
{
pool_error("Could not read backend status file as %s. reason: %s",
fnamebuf, strerror(errno));
fclose(fd);
return -1;
}
fclose(fd);
for (i=0;i< pool_config->backend_desc->num_backends;i++)
{
if (backend_rec.status[i] == CON_DOWN)
BACKEND_INFO(i).backend_status = CON_DOWN;
else
{
BACKEND_INFO(i).backend_status = CON_CONNECT_WAIT;
someone_wakeup = true;
}
}
/*
* If no one woke up, we regard the status file bogus
*/
if (someone_wakeup == false)
{
for (i=0;i< pool_config->backend_desc->num_backends;i++)
{
BACKEND_INFO(i).backend_status = CON_CONNECT_WAIT;
}
}
return 0;
}
/*
* Deletes a shared memory segment (called as an on_shmem_exit callback,
* hence funny argument list)
*/
static void
IpcMemoryDelete(int status, Datum shmId)
{
struct shmid_ds shmStat;
/*
* Is a previously-existing shmem segment still existing and in use?
*/
if (shmctl(shmId, IPC_STAT, &shmStat) < 0
&& (errno == EINVAL || errno == EACCES))
return;
else if (shmStat.shm_nattch != 0)
return;
if (shmctl(shmId, IPC_RMID, NULL) < 0)
pool_log("shmctl(%lu, %d, 0) failed: %s",
shmId, IPC_RMID, strerror(errno));
}
/*
* Call pgpool_recovery() function.
*/
static int exec_recovery(PGconn *conn, BackendInfo *backend, char stage)
{
PGresult *result;
char *hostname;
char *script;
int r;
if (strlen(backend->backend_hostname) == 0 || *(backend->backend_hostname) == '/')
hostname = "localhost";
else
hostname = backend->backend_hostname;
script = (stage == FIRST_STAGE) ?
pool_config->recovery_1st_stage_command : pool_config->recovery_2nd_stage_command;
if (script == NULL || strlen(script) == 0)
{
/* do not execute script */
return 0;
}
snprintf(recovery_command,
sizeof(recovery_command),
"SELECT pgpool_recovery('%s', '%s', '%s')",
script,
hostname,
backend->backend_data_directory);
pool_log("starting recovery command: \"%s\"", recovery_command);
pool_debug("exec_recovery: start recovery");
result = PQexec(conn, recovery_command);
r = (PQresultStatus(result) != PGRES_TUPLES_OK);
if (r != 0)
{
pool_error("exec_recovery: %s command failed at %s",
script,
(stage == FIRST_STAGE) ? "1st stage" : "2nd stage");
}
PQclear(result);
pool_debug("exec_recovery: finish recovery");
return r;
}
int
wd_IP_down(void)
{
int rtn = WD_OK;
char path[WD_MAX_PATH_LEN];
char cmd[128];
int i;
if (strlen(pool_config->delegate_IP) == 0)
return WD_NG;
if (WD_List->delegate_ip_flag == 1)
{
WD_List->delegate_ip_flag = 0;
wd_get_cmd(cmd,pool_config->if_down_cmd);
snprintf(path, sizeof(path), "%s/%s", pool_config->ifconfig_path, cmd);
rtn = exec_ifconfig(path,pool_config->if_down_cmd);
if (rtn == WD_OK)
{
for (i = 0; i < 3; i++)
{
if (wd_is_unused_ip(pool_config->delegate_IP))
break;
}
if (i >= 3)
rtn = WD_NG;
}
if (rtn == WD_OK)
pool_log("wd_IP_down: ifconfig down succeeded");
else
pool_error("wd_IP_down: ifconfig down failed");
}
else
{
pool_debug("wd_IP_down: not delegate IP holder");
}
return rtn;
}
/*
* Connect to PostgreSQL server by using UNIX domain socket.
* If retry is true, retry to call connect() upon receiving EINTR error.
*/
int connect_unix_domain_socket_by_port(int port, char *socket_dir, bool retry)
{
struct sockaddr_un addr;
int fd;
int len;
fd = socket(AF_UNIX, SOCK_STREAM, 0);
if (fd == -1)
{
pool_error("connect_unix_domain_socket_by_port: socket() failed: %s", strerror(errno));
return -1;
}
memset((char *) &addr, 0, sizeof(addr));
addr.sun_family = AF_UNIX;
snprintf(addr.sun_path, sizeof(addr.sun_path), "%s/.s.PGSQL.%d", socket_dir, port);
len = sizeof(struct sockaddr_un);
for (;;)
{
if (exit_request) /* exit request already sent */
{
pool_log("connect_unix_domain_socket_by_port: exit request has been sent");
close(fd);
return -1;
}
if (connect(fd, (struct sockaddr *)&addr, len) < 0)
{
if ((errno == EINTR && retry) || errno == EAGAIN)
continue;
pool_error("connect_unix_domain_socket_by_port: connect() failed to %s: %s", addr.sun_path, strerror(errno));
close(fd);
return -1;
}
break;
}
return fd;
}
/*
* Convert logid/recoff style text to 64bit log location (LSN)
*/
static long text_to_lsn(char *text)
{
/*
* WAL segment size in bytes. XXX We should fetch this from
* PostgreSQL, rather than having fixed value.
*/
#define WALSEGMENTSIZE 16 * 1024 * 1024
unsigned int xlogid;
unsigned int xrecoff;
unsigned long long int lsn;
if (sscanf(text, "%X/%X", &xlogid, &xrecoff) != 2)
{
pool_error("text_to_lsn: wrong log location format: %s", text);
return 0;
}
lsn = xlogid * ((unsigned long long int)0xffffffff - WALSEGMENTSIZE) + xrecoff;
#ifdef DEBUG
pool_log("lsn: %X %X %llX", xlogid, xrecoff, lsn);
#endif
return lsn;
}
/*
* signal handler for SIGALRM
*
*/
static RETSIGTYPE authentication_timeout(int sig)
{
pool_log("authentication is timeout");
child_exit(1);
}
/*
* flush write buffer
*/
int pool_flush_it(POOL_CONNECTION *cp)
{
int sts;
int wlen;
int offset;
wlen = cp->wbufpo;
if (wlen == 0)
{
return 0;
}
offset = 0;
for (;;)
{
errno = 0;
#ifdef NOT_USED
if (!cp->isbackend)
{
fd_set writemask;
fd_set exceptmask;
FD_ZERO(&writemask);
FD_ZERO(&exceptmask);
FD_SET(cp->fd, &writemask);
FD_SET(cp->fd, &exceptmask);
sts = select(cp->fd+1, NULL, &writemask, &exceptmask, NULL);
if (sts == -1)
{
if (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK)
continue;
pool_error("pool_flush_it: select() failed. reason: %s", strerror(errno));
cp->wbufpo = 0;
return -1;
}
else if (sts == 0)
{
continue;
}
else if (FD_ISSET(cp->fd, &exceptmask))
{
pool_log("pool_flush_it: exception occured");
cp->wbufpo = 0;
return -1;
}
}
#endif
if (cp->ssl_active > 0) {
sts = pool_ssl_write(cp, cp->wbuf + offset, wlen);
} else {
sts = write(cp->fd, cp->wbuf + offset, wlen);
}
if (sts > 0)
{
wlen -= sts;
if (wlen == 0)
{
/* write completed */
break;
}
else if (wlen < 0)
{
pool_error("pool_flush_it: invalid write size %d", sts);
cp->wbufpo = 0;
return -1;
}
else
{
/* need to write remaining data */
offset += sts;
continue;
}
}
else if (errno == EAGAIN || errno == EINTR)
{
continue;
}
else
{
/* If this is the backend stream, report error. Otherwise
* just report debug message.
*/
if (cp->isbackend)
pool_error("pool_flush_it: write failed to backend (%d). reason: %s offset: %d wlen: %d",
cp->db_node_id, strerror(errno), offset, wlen);
else
pool_debug("pool_flush_it: write failed to frontend. reason: %s offset: %d wlen: %d",
strerror(errno), offset, wlen);
cp->wbufpo = 0;
return -1;
}
}
cp->wbufpo = 0;
return 0;
}
/*
* Removes a shared memory segment from process' address spaceq (called as
* an on_shmem_exit callback, hence funny argument list)
*/
static void
IpcMemoryDetach(int status, Datum shmaddr)
{
if (shmdt((void *) shmaddr) < 0)
pool_log("shmdt(%p) failed: %s", (void *) shmaddr, strerror(errno));
}
/*
* 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;
}
static int
wd_send_response(int sock, WdPacket * recv_pack)
{
int rtn = WD_NG;
WdInfo * p, *q;
WdNodeInfo * node;
WdLockInfo * lock;
WdPacket send_packet;
struct timeval tv;
char pack_str[WD_MAX_PACKET_STRING];
int pack_str_len;
char hash[(MD5_PASSWD_LEN+1)*2];
bool is_node_packet = false;
if (recv_pack == NULL)
{
return rtn;
}
memset(&send_packet, 0, sizeof(WdPacket));
p = &(recv_pack->wd_body.wd_info);
/* auhtentication */
if (strlen(pool_config->wd_authkey))
{
/* calculate hash from packet */
pack_str_len = wd_packet_to_string(*recv_pack, pack_str, sizeof(pack_str));
wd_calc_hash(pack_str, pack_str_len, hash);
if (strcmp(recv_pack->hash, hash))
{
pool_log("wd_send_response: watchdog authentication failed");
rtn = wd_authentication_failed(sock);
return rtn;
}
}
/* set response packet no */
switch (recv_pack->packet_no)
{
/* add request into the watchdog list */
case WD_ADD_REQ:
p = &(recv_pack->wd_body.wd_info);
if (wd_set_wd_list(p->hostname,p->pgpool_port, p->wd_port, p->delegate_ip, &(p->tv), p->status) > 0)
{
send_packet.packet_no = WD_ADD_ACCEPT;
}
else
{
send_packet.packet_no = WD_ADD_REJECT;
}
memcpy(&(send_packet.wd_body.wd_info), WD_MYSELF, sizeof(WdInfo));
break;
/* announce candidacy to be the new master */
case WD_STAND_FOR_MASTER:
p = &(recv_pack->wd_body.wd_info);
wd_set_wd_list(p->hostname,p->pgpool_port, p->wd_port, p->delegate_ip, &(p->tv), p->status);
/* check exist master */
if ((q = wd_is_alive_master()) != NULL)
{
/* vote against the candidate */
send_packet.packet_no = WD_MASTER_EXIST;
memcpy(&(send_packet.wd_body.wd_info), q, sizeof(WdInfo));
}
else
{
if (WD_MYSELF->tv.tv_sec <= p->tv.tv_sec )
{
memcpy(&tv,&(p->tv),sizeof(struct timeval));
tv.tv_sec += 1;
wd_set_myself(&tv, WD_NORMAL);
}
/* vote for the candidate */
send_packet.packet_no = WD_VOTE_YOU;
memcpy(&(send_packet.wd_body.wd_info), WD_MYSELF, sizeof(WdInfo));
}
break;
/* announce assumption to be the new master */
case WD_DECLARE_NEW_MASTER:
p = &(recv_pack->wd_body.wd_info);
wd_set_wd_list(p->hostname,p->pgpool_port, p->wd_port, p->delegate_ip, &(p->tv), p->status);
if (WD_MYSELF->status == WD_MASTER)
{
/* resign master server */
pool_log("wd_declare_new_master: ifconfig down to resign master server");
wd_IP_down();
wd_set_myself(NULL, WD_NORMAL);
}
send_packet.packet_no = WD_READY;
memcpy(&(send_packet.wd_body.wd_info), WD_MYSELF, sizeof(WdInfo));
break;
/* annouce to assume lock holder */
case WD_STAND_FOR_LOCK_HOLDER:
p = &(recv_pack->wd_body.wd_info);
wd_set_wd_list(p->hostname,p->pgpool_port, p->wd_port, p->delegate_ip, &(p->tv), p->status);
/* only master handles lock holder privilege */
if (WD_MYSELF->status == WD_MASTER)
{
/* if theare are no lock holder yet */
if (wd_get_lock_holder() != NULL)
{
send_packet.packet_no = WD_LOCK_HOLDER_EXIST;
}
}
memcpy(&(send_packet.wd_body.wd_info), WD_MYSELF, sizeof(WdInfo));
break;
case WD_DECLARE_LOCK_HOLDER:
p = &(recv_pack->wd_body.wd_info);
wd_set_wd_list(p->hostname,p->pgpool_port, p->wd_port, p->delegate_ip, &(p->tv), p->status);
wd_set_lock_holder(p, true);
send_packet.packet_no = WD_READY;
memcpy(&(send_packet.wd_body.wd_info), WD_MYSELF, sizeof(WdInfo));
break;
/* annouce to resigne lock holder */
case WD_RESIGN_LOCK_HOLDER:
p = &(recv_pack->wd_body.wd_info);
wd_set_wd_list(p->hostname,p->pgpool_port, p->wd_port, p->delegate_ip, &(p->tv), p->status);
wd_set_lock_holder(p, false);
send_packet.packet_no = WD_READY;
memcpy(&(send_packet.wd_body.wd_info), WD_MYSELF, sizeof(WdInfo));
break;
case WD_START_INTERLOCK:
p = &(recv_pack->wd_body.wd_info);
wd_set_wd_list(p->hostname,p->pgpool_port, p->wd_port, p->delegate_ip, &(p->tv), p->status);
wd_set_interlocking(p, true);
break;
case WD_END_INTERLOCK:
p = &(recv_pack->wd_body.wd_info);
wd_set_wd_list(p->hostname,p->pgpool_port, p->wd_port, p->delegate_ip, &(p->tv), p->status);
wd_set_interlocking(p, false);
break;
/* announce that server is down */
case WD_SERVER_DOWN:
p = &(recv_pack->wd_body.wd_info);
wd_set_wd_list(p->hostname,p->pgpool_port, p->wd_port, p->delegate_ip, &(p->tv), WD_DOWN);
send_packet.packet_no = WD_READY;
memcpy(&(send_packet.wd_body.wd_info), WD_MYSELF, sizeof(WdInfo));
if (wd_am_I_oldest() == WD_OK && WD_MYSELF->status != WD_MASTER)
{
wd_escalation();
}
break;
/* announce start online recovery */
case WD_START_RECOVERY:
if (*InRecovery != RECOVERY_INIT)
{
send_packet.packet_no = WD_NODE_FAILED;
}
else
{
send_packet.packet_no = WD_NODE_READY;
*InRecovery = RECOVERY_ONLINE;
if (wait_connection_closed() != 0)
{
send_packet.packet_no = WD_NODE_FAILED;
}
}
break;
case WD_END_RECOVERY:
send_packet.packet_no = WD_NODE_READY;
*InRecovery = RECOVERY_INIT;
kill(wd_ppid, SIGUSR2);
break;
case WD_FAILBACK_REQUEST:
node = &(recv_pack->wd_body.wd_node_info);
wd_set_node_mask(WD_FAILBACK_REQUEST,node->node_id_set,node->node_num);
is_node_packet = true;
send_packet.packet_no = WD_NODE_READY;
break;
case WD_DEGENERATE_BACKEND:
node = &(recv_pack->wd_body.wd_node_info);
wd_set_node_mask(WD_DEGENERATE_BACKEND,node->node_id_set, node->node_num);
is_node_packet = true;
send_packet.packet_no = WD_NODE_READY;
break;
case WD_PROMOTE_BACKEND:
node = &(recv_pack->wd_body.wd_node_info);
wd_set_node_mask(WD_PROMOTE_BACKEND,node->node_id_set, node->node_num);
is_node_packet = true;
send_packet.packet_no = WD_NODE_READY;
break;
case WD_UNLOCK_REQUEST:
lock = &(recv_pack->wd_body.wd_lock_info);
wd_set_lock(lock->lock_id, false);
send_packet.packet_no = WD_LOCK_READY;
break;
default:
send_packet.packet_no = WD_INVALID;
memcpy(&(send_packet.wd_body.wd_info), WD_MYSELF, sizeof(WdInfo));
break;
}
/* send response packet */
rtn = wd_send_packet(sock, &send_packet);
/* send node request signal.
* wd_node_request_singnal() uses a semaphore lock internally, so should be
* called after sending a response pakcet to prevent dead lock.
*/
if (is_node_packet)
wd_node_request_signal(recv_pack->packet_no, node);
return rtn;
}
/*
* Connect to PostgreSQL server by using INET domain socket.
* If retry is true, retry to call connect() upon receiving EINTR error.
*/
int connect_inet_domain_socket_by_port(char *host, int port, bool retry)
{
int fd;
int len;
int on = 1;
struct sockaddr_in addr;
struct hostent *hp;
fd = socket(AF_INET, SOCK_STREAM, 0);
if (fd < 0)
{
pool_error("connect_inet_domain_socket_by_port: socket() failed: %s", strerror(errno));
return -1;
}
/* set nodelay */
if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY,
(char *) &on,
sizeof(on)) < 0)
{
pool_error("connect_inet_domain_socket_by_port: setsockopt() failed: %s", strerror(errno));
close(fd);
return -1;
}
memset((char *) &addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
len = sizeof(struct sockaddr_in);
hp = gethostbyname(host);
if ((hp == NULL) || (hp->h_addrtype != AF_INET))
{
pool_error("connect_inet_domain_socket: gethostbyname() failed: %s host: %s", hstrerror(h_errno), host);
close(fd);
return -1;
}
memmove((char *) &(addr.sin_addr),
(char *) hp->h_addr,
hp->h_length);
pool_set_nonblock(fd);
for (;;)
{
if (exit_request) /* exit request already sent */
{
pool_log("connect_inet_domain_socket_by_port: exit request has been sent");
close(fd);
return -1;
}
if (health_check_timer_expired) /* has health check timer expired */
{
pool_log("connect_inet_domain_socket_by_port: health check timer expired");
close(fd);
return -1;
}
if (connect(fd, (struct sockaddr *)&addr, len) < 0)
{
if (errno == EISCONN)
{
/* Socket is already connected */
break;
}
if ((errno == EINTR && retry) || errno == EAGAIN)
continue;
/* Non block fd could return these */
if (errno == EINPROGRESS || errno == EALREADY)
continue;
pool_error("connect_inet_domain_socket: connect() failed: %s",strerror(errno));
close(fd);
return -1;
}
break;
}
pool_unset_nonblock(fd);
return fd;
}
/*
* create actual connections to backends
*/
static POOL_CONNECTION_POOL *new_connection(POOL_CONNECTION_POOL *p)
{
POOL_CONNECTION_POOL_SLOT *s;
int active_backend_count = 0;
int i;
for (i=0;i<NUM_BACKENDS;i++)
{
pool_debug("new_connection: connecting %d backend", i);
if (!VALID_BACKEND(i))
{
pool_debug("new_connection: skipping slot %d because backend_status = %d",
i, BACKEND_INFO(i).backend_status);
continue;
}
s = malloc(sizeof(POOL_CONNECTION_POOL_SLOT));
if (s == NULL)
{
pool_error("new_connection: malloc() failed");
return NULL;
}
if (create_cp(s, i) == NULL)
{
/* connection failed. mark this backend down */
pool_error("new_connection: create_cp() failed");
/* If fail_over_on_backend_error is true, do failover.
* Otherwise, just exit this session.
*/
if (pool_config->fail_over_on_backend_error)
{
notice_backend_error(i);
}
else
{
pool_log("new_connection: do not failover because fail_over_on_backend_error is off");
}
child_exit(1);
}
p->info[i].create_time = time(NULL);
p->slots[i] = s;
if (pool_init_params(&s->con->params))
{
return NULL;
}
BACKEND_INFO(i).backend_status = CON_UP;
active_backend_count++;
}
if (active_backend_count > 0)
{
return p;
}
return NULL;
}
/*
* read a string until EOF or NULL is encountered.
* if line is not 0, read until new line is encountered.
*/
char *pool_read_string(POOL_CONNECTION *cp, int *len, int line)
{
int readp;
int readsize;
int readlen;
int strlength;
int flag;
int consume_size;
#ifdef DEBUG
static char pbuf[READBUFSZ];
#endif
*len = 0;
readp = 0;
/* initialize read buffer */
if (cp->sbufsz == 0)
{
cp->sbuf = malloc(READBUFSZ);
if (cp->sbuf == NULL)
{
pool_error("pool_read_string: malloc failed");
return NULL;
}
cp->sbufsz = READBUFSZ;
*cp->sbuf = '\0';
}
/* any pending data? */
if (cp->len)
{
if (line)
strlength = mystrlinelen(cp->hp+cp->po, cp->len, &flag);
else
strlength = mystrlen(cp->hp+cp->po, cp->len, &flag);
/* buffer is too small? */
if ((strlength + 1) > cp->sbufsz)
{
cp->sbufsz = ((strlength+1)/READBUFSZ+1)*READBUFSZ;
cp->sbuf = realloc(cp->sbuf, cp->sbufsz);
if (cp->sbuf == NULL)
{
pool_error("pool_read_string: realloc failed");
return NULL;
}
}
/* consume pending and save to read string buffer */
consume_size = consume_pending_data(cp, cp->sbuf, strlength);
*len = strlength;
/* is the string null terminated? */
if (consume_size == strlength && !flag)
{
/* not null or line terminated.
* we need to read more since we have not encountered NULL or new line yet
*/
readsize = cp->sbufsz - strlength;
readp = strlength;
}
else
{
pool_debug("pool_read_string: read all from pending data. po:%d len:%d",
cp->po, cp->len);
return cp->sbuf;
}
} else
{
readsize = cp->sbufsz;
}
for (;;)
{
if (pool_check_fd(cp))
{
if (!IS_MASTER_NODE_ID(cp->db_node_id))
{
pool_log("pool_read_string: data is not ready in DB node:%d. abort this session",
cp->db_node_id);
exit(1);
}
else
{
pool_error("pool_read_string: pool_check_fd failed (%s)", strerror(errno));
return NULL;
}
}
if (cp->ssl_active > 0) {
readlen = pool_ssl_read(cp, cp->sbuf+readp, readsize);
} else {
readlen = read(cp->fd, cp->sbuf+readp, readsize);
}
if (readlen == -1)
{
pool_error("pool_read_string: read() failed. reason:%s", strerror(errno));
if (cp->isbackend)
{
notice_backend_error(cp->db_node_id);
child_exit(1);
}
else
{
return NULL;
}
}
else if (readlen == 0) /* EOF detected */
{
/*
* just returns an error, not trigger failover or degeneration
*/
pool_error("pool_read_string: read () EOF detected");
return NULL;
}
/* check overrun */
if (line)
strlength = mystrlinelen(cp->sbuf+readp, readlen, &flag);
else
strlength = mystrlen(cp->sbuf+readp, readlen, &flag);
if (strlength < readlen)
{
save_pending_data(cp, cp->sbuf+readp+strlength, readlen-strlength);
*len += strlength;
pool_debug("pool_read_string: total result %d with pending data po:%d len:%d", *len, cp->po, cp->len);
return cp->sbuf;
}
*len += readlen;
/* encountered null or newline? */
if (flag)
{
/* ok we have read all data */
pool_debug("pool_read_string: total result %d ", *len);
break;
}
readp += readlen;
readsize = READBUFSZ;
if ((*len+readsize) > cp->sbufsz)
{
cp->sbufsz += READBUFSZ;
cp->sbuf = realloc(cp->sbuf, cp->sbufsz);
if (cp->sbuf == NULL)
{
pool_error("pool_read_string: realloc failed");
return NULL;
}
}
}
return cp->sbuf;
}
/*
* process cancel request
*/
void cancel_request(CancelPacket *sp)
{
int len;
int fd;
POOL_CONNECTION *con;
int i,j,k;
ConnectionInfo *c = NULL;
CancelPacket cp;
bool found = false;
pool_debug("Cancel request received");
/* look for cancel key from shmem info */
for (i=0;i<pool_config->num_init_children;i++)
{
for (j=0;j<pool_config->max_pool;j++)
{
for (k=0;k<NUM_BACKENDS;k++)
{
c = pool_coninfo(i, j, k);
pool_debug("con_info: address:%p database:%s user:%s pid:%d key:%d i:%d",
c, c->database, c->user, ntohl(c->pid), ntohl(c->key),i);
if (c->pid == sp->pid && c->key == sp->key)
{
pool_debug("found pid:%d key:%d i:%d",ntohl(c->pid), ntohl(c->key),i);
c = pool_coninfo(i, j, 0);
found = true;
goto found;
}
}
}
}
found:
if (!found)
{
pool_error("cancel_request: invalid cancel key: pid:%d key:%d",ntohl(sp->pid), ntohl(sp->key));
return; /* invalid key */
}
for (i=0;i<NUM_BACKENDS;i++,c++)
{
if (!VALID_BACKEND(i))
continue;
if (*(BACKEND_INFO(i).backend_hostname) == '/')
fd = connect_unix_domain_socket(i, TRUE);
else
fd = connect_inet_domain_socket(i, TRUE);
if (fd < 0)
{
pool_error("Could not create socket for sending cancel request for backend %d", i);
return;
}
con = pool_open(fd);
if (con == NULL)
return;
len = htonl(sizeof(len) + sizeof(CancelPacket));
pool_write(con, &len, sizeof(len));
cp.protoVersion = sp->protoVersion;
cp.pid = c->pid;
cp.key = c->key;
pool_log("cancel_request: canceling backend pid:%d key: %d", ntohl(cp.pid),ntohl(cp.key));
if (pool_write_and_flush(con, &cp, sizeof(CancelPacket)) < 0)
pool_error("Could not send cancel request packet for backend %d", i);
pool_close(con);
/*
* this is needed to ensure that the next DB node executes the
* query supposed to be canceled.
*/
sleep(1);
}
}
int
wd_reaper_watchdog(pid_t pid, int status)
{
int i;
/* watchdog lifecheck process exits */
if (pid == lifecheck_pid)
{
if (WIFSIGNALED(status))
pool_debug("watchdog lifecheck process %d exits with status %d by signal %d",
pid, status, WTERMSIG(status));
else
pool_debug("watchdog lifecheck process %d exits with status %d", pid, status);
lifecheck_pid = fork_a_lifecheck(1);
if (lifecheck_pid < 0)
{
pool_error("wd_reaper: fork a watchdog lifecheck process failed");
return 0;
}
pool_log("fork a new watchdog lifecheck pid %d", lifecheck_pid);
}
/* watchdog child process exits */
else if (pid == child_pid)
{
if (WIFSIGNALED(status))
pool_debug("watchdog child process %d exits with status %d by signal %d",
pid, status, WTERMSIG(status));
else
pool_debug("watchdog child process %d exits with status %d", pid, status);
child_pid = wd_child(1);
if (child_pid < 0)
{
pool_error("wd_reaper: fork a watchdog child process failed");
return 0;
}
pool_log("fork a new watchdog child pid %d", child_pid);
}
/* receiver/sender process exits */
else
{
for (i = 0; i < pool_config->num_hb_if; i++)
{
if (pid == hb_receiver_pid[i])
{
if (WIFSIGNALED(status))
pool_debug("watchdog heartbeat receiver process %d exits with status %d by signal %d",
pid, status, WTERMSIG(status));
else
pool_debug("watchdog heartbeat receiver process %d exits with status %d", pid, status);
hb_receiver_pid[i] = wd_hb_receiver(1, pool_config->hb_if[i]);
if (hb_receiver_pid[i] < 0)
{
pool_error("wd_reaper: fork a watchdog heartbeat receiver process failed");
return 0;
}
pool_log("fork a new watchdog heartbeat receiver: pid %d", hb_receiver_pid[i]);
break;
}
else if (pid == hb_sender_pid[i])
{
if (WIFSIGNALED(status))
pool_debug("watchdog heartbeat sender process %d exits with status %d by signal %d",
pid, status, WTERMSIG(status));
else
pool_debug("watchdog heartbeat sender process %d exits with status %d", pid, status);
hb_sender_pid[i] = wd_hb_sender(1, pool_config->hb_if[i]);
if (hb_sender_pid[i] < 0)
{
pool_error("wd_reaper: fork a watchdog heartbeat sender process failed");
return 0;
}
pool_log("fork a new watchdog heartbeat sender: pid %d", hb_sender_pid[i]);
break;
}
}
}
return 1;
}
/*
* perform accept() and return new fd
*/
static POOL_CONNECTION *do_accept(int unix_fd, int inet_fd, struct timeval *timeout)
{
fd_set readmask;
int fds;
int save_errno;
SockAddr saddr;
int fd = 0;
int afd;
int inet = 0;
POOL_CONNECTION *cp;
#ifdef ACCEPT_PERFORMANCE
struct timeval now1, now2;
static long atime;
static int cnt;
#endif
struct timeval *timeoutval;
struct timeval tv1, tv2, tmback = {0, 0};
set_ps_display("wait for connection request", false);
/* Destroy session context for just in case... */
pool_session_context_destroy();
FD_ZERO(&readmask);
FD_SET(unix_fd, &readmask);
if (inet_fd)
FD_SET(inet_fd, &readmask);
if (timeout->tv_sec == 0 && timeout->tv_usec == 0)
timeoutval = NULL;
else
{
timeoutval = timeout;
tmback.tv_sec = timeout->tv_sec;
tmback.tv_usec = timeout->tv_usec;
gettimeofday(&tv1, NULL);
#ifdef DEBUG
pool_log("before select = {%d, %d}", timeoutval->tv_sec, timeoutval->tv_usec);
pool_log("g:before select = {%d, %d}", tv1.tv_sec, tv1.tv_usec);
#endif
}
fds = select(Max(unix_fd, inet_fd)+1, &readmask, NULL, NULL, timeoutval);
save_errno = errno;
/* check backend timer is expired */
if (backend_timer_expired)
{
pool_backend_timer();
backend_timer_expired = 0;
}
/*
* following code fragment computes remaining timeout val in a
* portable way. Linux does this automatically but other platforms do not.
*/
if (timeoutval)
{
gettimeofday(&tv2, NULL);
tmback.tv_usec -= tv2.tv_usec - tv1.tv_usec;
tmback.tv_sec -= tv2.tv_sec - tv1.tv_sec;
if (tmback.tv_usec < 0)
{
tmback.tv_sec--;
if (tmback.tv_sec < 0)
{
timeout->tv_sec = 0;
timeout->tv_usec = 0;
}
else
{
tmback.tv_usec += 1000000;
timeout->tv_sec = tmback.tv_sec;
timeout->tv_usec = tmback.tv_usec;
}
}
#ifdef DEBUG
pool_log("g:after select = {%d, %d}", tv2.tv_sec, tv2.tv_usec);
pool_log("after select = {%d, %d}", timeout->tv_sec, timeout->tv_usec);
#endif
}
errno = save_errno;
if (fds == -1)
{
if (errno == EAGAIN || errno == EINTR)
return NULL;
pool_error("select() failed. reason %s", strerror(errno));
return NULL;
}
/* timeout */
if (fds == 0)
{
return NULL;
}
if (FD_ISSET(unix_fd, &readmask))
{
fd = unix_fd;
}
if (FD_ISSET(inet_fd, &readmask))
{
fd = inet_fd;
inet++;
}
/*
* Note that some SysV systems do not work here. For those
* systems, we need some locking mechanism for the fd.
*/
memset(&saddr, 0, sizeof(saddr));
saddr.salen = sizeof(saddr.addr);
#ifdef ACCEPT_PERFORMANCE
gettimeofday(&now1,0);
#endif
retry_accept:
/* wait if recovery is started */
while (*InRecovery == 1)
{
pause();
}
afd = accept(fd, (struct sockaddr *)&saddr.addr, &saddr.salen);
save_errno = errno;
/* check backend timer is expired */
if (backend_timer_expired)
{
pool_backend_timer();
backend_timer_expired = 0;
}
errno = save_errno;
if (afd < 0)
{
if (errno == EINTR && *InRecovery)
goto retry_accept;
/*
* "Resource temporarily unavailable" (EAGAIN or EWOULDBLOCK)
* can be silently ignored. And EINTR can be ignored.
*/
if (errno != EAGAIN && errno != EWOULDBLOCK && errno != EINTR)
pool_error("accept() failed. reason: %s", strerror(errno));
return NULL;
}
#ifdef ACCEPT_PERFORMANCE
gettimeofday(&now2,0);
atime += (now2.tv_sec - now1.tv_sec)*1000000 + (now2.tv_usec - now1.tv_usec);
cnt++;
if (cnt % 100 == 0)
{
pool_log("cnt: %d atime: %ld", cnt, atime);
}
#endif
/* reload config file */
if (got_sighup)
{
pool_get_config(get_config_file_name(), RELOAD_CONFIG);
if (pool_config->enable_pool_hba)
{
load_hba(get_hba_file_name());
if (strcmp("", pool_config->pool_passwd))
pool_reopen_passwd_file();
}
if (pool_config->parallel_mode)
pool_memset_system_db_info(system_db_info->info);
got_sighup = 0;
}
connection_count_up();
accepted = 1;
if (pool_config->parallel_mode)
{
/*
* do not accept new connection if any of DB node or SystemDB is down when operating in
* parallel mode
*/
int i;
for (i=0;i<NUM_BACKENDS;i++)
{
if (BACKEND_INFO(i).backend_status == CON_DOWN || SYSDB_STATUS == CON_DOWN)
{
StartupPacket *sp;
char *msg = "pgpool is not available in parallel query mode";
if (SYSDB_STATUS == CON_DOWN)
pool_log("Cannot accept() new connection. SystemDB is down");
else
pool_log("Cannot accept() new connection. %d th backend is down", i);
if ((cp = pool_open(afd)) == NULL)
{
close(afd);
child_exit(1);
}
sp = read_startup_packet(cp);
if (sp == NULL)
{
/* failed to read the startup packet. return to the accept() loop */
pool_close(cp);
child_exit(1);
}
pool_debug("do_accept: send error message to frontend");
if (sp->major == PROTO_MAJOR_V3)
{
char buf[256];
if (SYSDB_STATUS == CON_DOWN)
snprintf(buf, sizeof(buf), "SystemDB is down");
else
snprintf(buf, sizeof(buf), "%d th backend is down", i);
pool_send_error_message(cp, sp->major, "08S01",
msg,
buf,
((SYSDB_STATUS == CON_DOWN) ? "repair the SystemDB and restart pgpool"
: "repair the backend and restart pgpool"),
__FILE__,
__LINE__);
}
else
{
pool_send_error_message(cp, sp->major,
0,
msg,
"",
"",
"",
0);
}
pool_close(cp);
child_exit(1);
}
}
}
else
{
/*
* do not accept new connection if all DB nodes are down when operating in
* non parallel mode
*/
int i;
int found = 0;
for (i=0;i<NUM_BACKENDS;i++)
{
if (VALID_BACKEND(i))
{
found = 1;
}
}
if (found == 0)
{
pool_log("Cannot accept() new connection. all backends are down");
child_exit(1);
}
}
pool_debug("I am %d accept fd %d", getpid(), afd);
pool_getnameinfo_all(&saddr, remote_host, remote_port);
snprintf(remote_ps_data, sizeof(remote_ps_data),
remote_port[0] == '\0' ? "%s" : "%s(%s)",
remote_host, remote_port);
set_ps_display("accept connection", false);
/* log who is connecting */
if (pool_config->log_connections)
{
pool_log("connection received: host=%s%s%s",
remote_host, remote_port[0] ? " port=" : "", remote_port);
}
/* set NODELAY and KEEPALIVE options if INET connection */
if (inet)
{
int on = 1;
if (setsockopt(afd, IPPROTO_TCP, TCP_NODELAY,
(char *) &on,
sizeof(on)) < 0)
{
pool_error("do_accept: setsockopt() failed: %s", strerror(errno));
close(afd);
return NULL;
}
if (setsockopt(afd, SOL_SOCKET, SO_KEEPALIVE,
(char *) &on,
sizeof(on)) < 0)
{
pool_error("do_accept: setsockopt() failed: %s", strerror(errno));
close(afd);
return NULL;
}
}
if ((cp = pool_open(afd)) == NULL)
{
close(afd);
return NULL;
}
/* save ip address for hba */
memcpy(&cp->raddr, &saddr, sizeof(SockAddr));
if (cp->raddr.addr.ss_family == 0)
cp->raddr.addr.ss_family = AF_UNIX;
return cp;
}
/*
* 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);
}