mirror of
https://github.com/postgrespro/pg_probackup.git
synced 2024-11-25 09:01:48 +02:00
119 lines
2.3 KiB
C
119 lines
2.3 KiB
C
/*-------------------------------------------------------------------------
|
|
*
|
|
* status.c
|
|
*
|
|
* Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
|
|
*
|
|
* Monitor status of a PostgreSQL server.
|
|
*
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
|
|
|
|
#include "postgres_fe.h"
|
|
|
|
#include <signal.h>
|
|
#include <sys/types.h>
|
|
#include <unistd.h>
|
|
|
|
#include "pg_rman.h"
|
|
|
|
/* PID can be negative for standalone backend */
|
|
typedef long pgpid_t;
|
|
|
|
static pgpid_t get_pgpid(void);
|
|
static bool postmaster_is_alive(pid_t pid);
|
|
|
|
/*
|
|
* get_pgpid
|
|
*
|
|
* Get PID of postmaster, by scanning postmaster.pid.
|
|
*/
|
|
static pgpid_t
|
|
get_pgpid(void)
|
|
{
|
|
FILE *pidf;
|
|
long pid;
|
|
char pid_file[MAXPGPATH];
|
|
|
|
snprintf(pid_file, lengthof(pid_file), "%s/postmaster.pid", pgdata);
|
|
|
|
pidf = fopen(pid_file, "r");
|
|
if (pidf == NULL)
|
|
{
|
|
/* No pid file, not an error on startup */
|
|
if (errno == ENOENT)
|
|
return 0;
|
|
else
|
|
{
|
|
elog(ERROR_SYSTEM, _("could not open PID file \"%s\": %s\n"),
|
|
pid_file, strerror(errno));
|
|
}
|
|
}
|
|
if (fscanf(pidf, "%ld", &pid) != 1)
|
|
{
|
|
/* Is the file empty? */
|
|
if (ftell(pidf) == 0 && feof(pidf))
|
|
elog(ERROR_SYSTEM, _("the PID file \"%s\" is empty\n"),
|
|
pid_file);
|
|
else
|
|
elog(ERROR_SYSTEM, _("invalid data in PID file \"%s\"\n"),
|
|
pid_file);
|
|
}
|
|
fclose(pidf);
|
|
return (pgpid_t) pid;
|
|
}
|
|
|
|
/*
|
|
* postmaster_is_alive
|
|
*
|
|
* Check whether postmaster is alive or not.
|
|
*/
|
|
static bool
|
|
postmaster_is_alive(pid_t pid)
|
|
{
|
|
/*
|
|
* Test to see if the process is still there. Note that we do not
|
|
* consider an EPERM failure to mean that the process is still there;
|
|
* EPERM must mean that the given PID belongs to some other userid, and
|
|
* considering the permissions on $PGDATA, that means it's not the
|
|
* postmaster we are after.
|
|
*
|
|
* Don't believe that our own PID or parent shell's PID is the postmaster,
|
|
* either. (Windows hasn't got getppid(), though.)
|
|
*/
|
|
if (pid == getpid())
|
|
return false;
|
|
#ifndef WIN32
|
|
if (pid == getppid())
|
|
return false;
|
|
#endif
|
|
if (kill(pid, 0) == 0)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* is_pg_running
|
|
*
|
|
*
|
|
*/
|
|
bool
|
|
is_pg_running(void)
|
|
{
|
|
pgpid_t pid;
|
|
|
|
pid = get_pgpid();
|
|
|
|
/* 0 means no pid file */
|
|
if (pid == 0)
|
|
return false;
|
|
|
|
/* Case of a standalone backend */
|
|
if (pid < 0)
|
|
pid = -pid;
|
|
|
|
/* Check if postmaster is alive */
|
|
return postmaster_is_alive((pid_t) pid);
|
|
}
|