postgresql/contrib/pg_upgrade/server.c

353 lines
8.2 KiB
C

/*
* server.c
*
* database server functions
*
* Copyright (c) 2010-2011, PostgreSQL Global Development Group
* contrib/pg_upgrade/server.c
*/
#include "pg_upgrade.h"
#define POSTMASTER_UPTIME 20
#define STARTUP_WARNING_TRIES 2
static pgpid_t get_postmaster_pid(const char *datadir);
static bool test_server_conn(ClusterInfo *cluster, int timeout);
/*
* connectToServer()
*
* Connects to the desired database on the designated server.
* If the connection attempt fails, this function logs an error
* message and calls exit() to kill the program.
*/
PGconn *
connectToServer(ClusterInfo *cluster, const char *db_name)
{
unsigned short port = cluster->port;
char connectString[MAXPGPATH];
PGconn *conn;
snprintf(connectString, sizeof(connectString),
"dbname = '%s' user = '%s' port = %d", db_name, os_info.user, port);
conn = PQconnectdb(connectString);
if (conn == NULL || PQstatus(conn) != CONNECTION_OK)
{
pg_log(PG_REPORT, "Connection to database failed: %s\n",
PQerrorMessage(conn));
if (conn)
PQfinish(conn);
printf("Failure, exiting\n");
exit(1);
}
return conn;
}
/*
* executeQueryOrDie()
*
* Formats a query string from the given arguments and executes the
* resulting query. If the query fails, this function logs an error
* message and calls exit() to kill the program.
*/
PGresult *
executeQueryOrDie(PGconn *conn, const char *fmt,...)
{
static char command[8192];
va_list args;
PGresult *result;
ExecStatusType status;
va_start(args, fmt);
vsnprintf(command, sizeof(command), fmt, args);
va_end(args);
pg_log(PG_DEBUG, "executing: %s\n", command);
result = PQexec(conn, command);
status = PQresultStatus(result);
if ((status != PGRES_TUPLES_OK) && (status != PGRES_COMMAND_OK))
{
pg_log(PG_REPORT, "DB command failed\n%s\n%s\n", command,
PQerrorMessage(conn));
PQclear(result);
PQfinish(conn);
printf("Failure, exiting\n");
exit(1);
}
else
return result;
}
/*
* get_postmaster_pid()
*
* Returns the pid of the postmaster running on datadir. pid is retrieved
* from the postmaster.pid file
*/
static pgpid_t
get_postmaster_pid(const char *datadir)
{
FILE *pidf;
long pid;
char pid_file[MAXPGPATH];
snprintf(pid_file, sizeof(pid_file), "%s/postmaster.pid", datadir);
pidf = fopen(pid_file, "r");
if (pidf == NULL)
return (pgpid_t) 0;
if (fscanf(pidf, "%ld", &pid) != 1)
{
fclose(pidf);
pg_log(PG_FATAL, "%s: invalid data in PID file \"%s\"\n",
os_info.progname, pid_file);
}
fclose(pidf);
return (pgpid_t) pid;
}
/*
* get_major_server_version()
*
* gets the version (in unsigned int form) for the given "datadir". Assumes
* that datadir is an absolute path to a valid pgdata directory. The version
* is retrieved by reading the PG_VERSION file.
*/
uint32
get_major_server_version(ClusterInfo *cluster)
{
const char *datadir = cluster->pgdata;
FILE *version_fd;
char ver_filename[MAXPGPATH];
int integer_version = 0;
int fractional_version = 0;
snprintf(ver_filename, sizeof(ver_filename), "%s/PG_VERSION", datadir);
if ((version_fd = fopen(ver_filename, "r")) == NULL)
return 0;
if (fscanf(version_fd, "%63s", cluster->major_version_str) == 0 ||
sscanf(cluster->major_version_str, "%d.%d", &integer_version,
&fractional_version) != 2)
pg_log(PG_FATAL, "could not get version from %s\n", datadir);
fclose(version_fd);
return (100 * integer_version + fractional_version) * 100;
}
static void
#ifdef HAVE_ATEXIT
stop_postmaster_atexit(void)
#else
stop_postmaster_on_exit(int exitstatus, void *arg)
#endif
{
stop_postmaster(true, true);
}
void
start_postmaster(ClusterInfo *cluster, bool quiet)
{
char cmd[MAXPGPATH];
const char *bindir;
const char *datadir;
unsigned short port;
bool exit_hook_registered = false;
bindir = cluster->bindir;
datadir = cluster->pgdata;
port = cluster->port;
if (!exit_hook_registered)
{
#ifdef HAVE_ATEXIT
atexit(stop_postmaster_atexit);
#else
on_exit(stop_postmaster_on_exit);
#endif
exit_hook_registered = true;
}
/*
* On Win32, we can't send both pg_upgrade output and pg_ctl output to the
* same file because we get the error: "The process cannot access the file
* because it is being used by another process." so we have to send all
* other output to 'nul'.
*
* Using autovacuum=off disables cleanup vacuum and analyze, but
* freeze vacuums can still happen, so we set
* autovacuum_freeze_max_age to its maximum. We assume all datfrozenxid
* and relfrozen values are less than a gap of 2000000000 from the current
* xid counter, so autovacuum will not touch them.
*/
snprintf(cmd, sizeof(cmd),
SYSTEMQUOTE "\"%s/pg_ctl\" -l \"%s\" -D \"%s\" "
"-o \"-p %d -c autovacuum=off "
"-c autovacuum_freeze_max_age=2000000000\" "
"start >> \"%s\" 2>&1" SYSTEMQUOTE,
bindir,
#ifndef WIN32
log_opts.filename, datadir, port, log_opts.filename);
#else
DEVNULL, datadir, port, DEVNULL);
#endif
exec_prog(true, "%s", cmd);
/* wait for the server to start properly */
if (test_server_conn(cluster, POSTMASTER_UPTIME) == false)
pg_log(PG_FATAL, " Unable to start %s postmaster with the command: %s\nPerhaps pg_hba.conf was not set to \"trust\".",
CLUSTER_NAME(cluster), cmd);
if ((os_info.postmasterPID = get_postmaster_pid(datadir)) == 0)
pg_log(PG_FATAL, " Unable to get postmaster pid\n");
os_info.running_cluster = cluster;
}
void
stop_postmaster(bool fast, bool quiet)
{
char cmd[MAXPGPATH];
const char *bindir;
const char *datadir;
if (os_info.running_cluster == &old_cluster)
{
bindir = old_cluster.bindir;
datadir = old_cluster.pgdata;
}
else if (os_info.running_cluster == &new_cluster)
{
bindir = new_cluster.bindir;
datadir = new_cluster.pgdata;
}
else
return; /* no cluster running */
/* See comment in start_postmaster() about why win32 output is ignored. */
snprintf(cmd, sizeof(cmd),
SYSTEMQUOTE "\"%s/pg_ctl\" -l \"%s\" -D \"%s\" %s stop >> "
"\"%s\" 2>&1" SYSTEMQUOTE,
bindir,
#ifndef WIN32
log_opts.filename, datadir, fast ? "-m fast" : "", log_opts.filename);
#else
DEVNULL, datadir, fast ? "-m fast" : "", DEVNULL);
#endif
exec_prog(fast ? false : true, "%s", cmd);
os_info.postmasterPID = 0;
os_info.running_cluster = NULL;
}
/*
* test_server_conn()
*
* tests whether postmaster is running or not by trying to connect
* to it. If connection is unsuccessfull we do a sleep of 1 sec and then
* try the connection again. This process continues "timeout" times.
*
* Returns true if the connection attempt was successfull, false otherwise.
*/
static bool
test_server_conn(ClusterInfo *cluster, int timeout)
{
unsigned short port = cluster->port;
PGconn *conn = NULL;
char con_opts[MAX_STRING];
int tries;
bool ret = false;
snprintf(con_opts, sizeof(con_opts),
"dbname = 'template1' user = '%s' port = %d ", os_info.user, port);
for (tries = 0; tries < timeout; tries++)
{
sleep(1);
if ((conn = PQconnectdb(con_opts)) != NULL &&
PQstatus(conn) == CONNECTION_OK)
{
PQfinish(conn);
ret = true;
break;
}
if (tries == STARTUP_WARNING_TRIES)
prep_status("Trying to start %s server ",
CLUSTER_NAME(cluster));
else if (tries > STARTUP_WARNING_TRIES)
pg_log(PG_REPORT, ".");
}
if (tries > STARTUP_WARNING_TRIES)
check_ok();
return ret;
}
/*
* check_for_libpq_envvars()
*
* tests whether any libpq environment variables are set.
* Since pg_upgrade connects to both the old and the new server,
* it is potentially dangerous to have any of these set.
*
* If any are found, will log them and cancel.
*/
void
check_for_libpq_envvars(void)
{
PQconninfoOption *option;
PQconninfoOption *start;
bool found = false;
/* Get valid libpq env vars from the PQconndefaults function */
start = option = PQconndefaults();
while (option->keyword != NULL)
{
const char *value;
if (option->envvar && (value = getenv(option->envvar)) && strlen(value) > 0)
{
found = true;
pg_log(PG_WARNING,
"libpq env var %-20s is currently set to: %s\n", option->envvar, value);
}
option++;
}
/* Free the memory that libpq allocated on our behalf */
PQconninfoFree(start);
if (found)
pg_log(PG_FATAL,
"libpq env vars have been found and listed above, please unset them for pg_upgrade\n");
}