pg_isready.c

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/*-------------------------------------------------------------------------
 *
 * pg_isready --- checks the status of the PostgreSQL server
 *
 * Copyright (c) 2013-2026, PostgreSQL Global Development Group
 *
 * src/bin/scripts/pg_isready.c
 *
 *-------------------------------------------------------------------------
 */
 
#include "postgres_fe.h"
#include "common.h"
#include "common/logging.h"
#include "fe_utils/option_utils.h"
 
#define DEFAULT_CONNECT_TIMEOUT "3"
 
static void
            help(const char *progname);
 
int
main(int argc, char **argv)
{
    int         c;
 
    const char *progname;
 
    const char *pghost = NULL;
    const char *pgport = NULL;
    const char *pguser = NULL;
    const char *pgdbname = NULL;
    const char *connect_timeout = DEFAULT_CONNECT_TIMEOUT;
 
    const char *pghost_str = NULL;
    const char *pghostaddr_str = NULL;
    const char *pgport_str = NULL;
 
#define PARAMS_ARRAY_SIZE   7
 
    const char *keywords[PARAMS_ARRAY_SIZE];
    const char *values[PARAMS_ARRAY_SIZE];
 
    bool        quiet = false;
 
    PGPing      rv;
    PQconninfoOption *opts = NULL;
    PQconninfoOption *defs = NULL;
    PQconninfoOption *opt;
    PQconninfoOption *def;
    char       *errmsg = NULL;
 
    /*
     * We accept user and database as options to avoid useless errors from
     * connecting with invalid params
     */
 
    static struct option long_options[] = {
        {"dbname", required_argument, NULL, 'd'},
        {"host", required_argument, NULL, 'h'},
        {"port", required_argument, NULL, 'p'},
        {"quiet", no_argument, NULL, 'q'},
        {"timeout", required_argument, NULL, 't'},
        {"username", required_argument, NULL, 'U'},
        {NULL, 0, NULL, 0}
    };
 
    pg_logging_init(argv[0]);
    progname = get_progname(argv[0]);
    set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pgscripts"));
    handle_help_version_opts(argc, argv, progname, help);
 
    while ((c = getopt_long(argc, argv, "d:h:p:qt:U:", long_options, NULL)) != -1)
    {
        switch (c)
        {
            case 'd':
                pgdbname = pg_strdup(optarg);
                break;
            case 'h':
                pghost = pg_strdup(optarg);
                break;
            case 'p':
                pgport = pg_strdup(optarg);
                break;
            case 'q':
                quiet = true;
                break;
            case 't':
                connect_timeout = pg_strdup(optarg);
                break;
            case 'U':
                pguser = pg_strdup(optarg);
                break;
            default:
                /* getopt_long already emitted a complaint */
                pg_log_error_hint("Try \"%s --help\" for more information.", progname);
 
                /*
                 * We need to make sure we don't return 1 here because someone
                 * checking the return code might infer unintended meaning
                 */
                exit(PQPING_NO_ATTEMPT);
        }
    }
 
    if (optind < argc)
    {
        pg_log_error("too many command-line arguments (first is \"%s\")",
                     argv[optind]);
        pg_log_error_hint("Try \"%s --help\" for more information.", progname);
 
        /*
         * We need to make sure we don't return 1 here because someone
         * checking the return code might infer unintended meaning
         */
        exit(PQPING_NO_ATTEMPT);
    }
 
    keywords[0] = "host";
    values[0] = pghost;
    keywords[1] = "port";
    values[1] = pgport;
    keywords[2] = "user";
    values[2] = pguser;
    keywords[3] = "dbname";
    values[3] = pgdbname;
    keywords[4] = "connect_timeout";
    values[4] = connect_timeout;
    keywords[5] = "fallback_application_name";
    values[5] = progname;
    keywords[6] = NULL;
    values[6] = NULL;
 
    /*
     * Get the host and port so we can display them in our output
     */
    if (pgdbname &&
        (strncmp(pgdbname, "postgresql://", 13) == 0 ||
         strncmp(pgdbname, "postgres://", 11) == 0 ||
         strchr(pgdbname, '=') != NULL))
    {
        opts = PQconninfoParse(pgdbname, &errmsg);
        if (opts == NULL)
        {
            pg_log_error("%s", errmsg);
            exit(PQPING_NO_ATTEMPT);
        }
    }
 
    defs = PQconndefaults();
    if (defs == NULL)
    {
        pg_log_error("could not fetch default options");
        exit(PQPING_NO_ATTEMPT);
    }
 
    for (opt = opts, def = defs; def->keyword; def++)
    {
        if (strcmp(def->keyword, "host") == 0)
        {
            if (opt && opt->val)
                pghost_str = opt->val;
            else if (pghost)
                pghost_str = pghost;
            else if (def->val)
                pghost_str = def->val;
            else
                pghost_str = DEFAULT_PGSOCKET_DIR;
        }
        else if (strcmp(def->keyword, "hostaddr") == 0)
        {
            if (opt && opt->val)
                pghostaddr_str = opt->val;
            else if (def->val)
                pghostaddr_str = def->val;
        }
        else if (strcmp(def->keyword, "port") == 0)
        {
            if (opt && opt->val)
                pgport_str = opt->val;
            else if (pgport)
                pgport_str = pgport;
            else if (def->val)
                pgport_str = def->val;
        }
 
        if (opt)
            opt++;
    }
 
    rv = PQpingParams(keywords, values, 1);
 
    if (!quiet)
    {
        printf("%s:%s - ",
               pghostaddr_str != NULL ? pghostaddr_str : pghost_str,
               pgport_str);
 
        switch (rv)
        {
            case PQPING_OK:
                printf(_("accepting connections\n"));
                break;
            case PQPING_REJECT:
                printf(_("rejecting connections\n"));
                break;
            case PQPING_NO_RESPONSE:
                printf(_("no response\n"));
                break;
            case PQPING_NO_ATTEMPT:
                printf(_("no attempt\n"));
                break;
            default:
                printf(_("unknown\n"));
        }
    }
 
    exit(rv);
}
 
static void
help(const char *progname)
{
    printf(_("%s issues a connection check to a PostgreSQL database.\n\n"), progname);
    printf(_("Usage:\n"));
    printf(_("  %s [OPTION]...\n"), progname);
 
    printf(_("\nOptions:\n"));
    printf(_("  -d, --dbname=DBNAME      database name\n"));
    printf(_("  -q, --quiet              run quietly\n"));
    printf(_("  -V, --version            output version information, then exit\n"));
    printf(_("  -?, --help               show this help, then exit\n"));
 
    printf(_("\nConnection options:\n"));
    printf(_("  -h, --host=HOSTNAME      database server host or socket directory\n"));
    printf(_("  -p, --port=PORT          database server port\n"));
    printf(_("  -t, --timeout=SECS       seconds to wait when attempting connection, 0 disables (default: %s)\n"), DEFAULT_CONNECT_TIMEOUT);
    printf(_("  -U, --username=USERNAME  user name to connect as\n"));
    printf(_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
    printf(_("%s home page: <%s>\n"), PACKAGE_NAME, PACKAGE_URL);
}