common.c File Reference

#include "postgres_fe.h"
#include <signal.h>
#include <unistd.h>
#include "common.h"
#include "fe_utils/connect.h"
#include "fe_utils/string_utils.h"

Include dependency graph for common.c:

Go to the source code of this file.

Macros
#define	PG_YESLETTER   gettext_noop("y")
#define	PG_NOLETTER   gettext_noop("n")

Functions
void	handle_help_version_opts (int argc, char *argv[], const char *fixed_progname, help_handler hlp)
PGconn *	connectDatabase (const char *dbname, const char *pghost, const char *pgport, const char *pguser, enum trivalue prompt_password, const char *progname, bool echo, bool fail_ok, bool allow_password_reuse)
PGconn *	connectMaintenanceDatabase (const char *maintenance_db, const char *pghost, const char *pgport, const char *pguser, enum trivalue prompt_password, const char *progname, bool echo)
PGresult *	executeQuery (PGconn *conn, const char *query, const char *progname, bool echo)
void	executeCommand (PGconn *conn, const char *query, const char *progname, bool echo)
bool	executeMaintenanceCommand (PGconn *conn, const char *query, bool echo)
static void	split_table_columns_spec (const char *spec, int encoding, char **table, const char **columns)
void	appendQualifiedRelation (PQExpBuffer buf, const char *spec, PGconn *conn, const char *progname, bool echo)
bool	yesno_prompt (const char *question)
void	SetCancelConn (PGconn *conn)
void	ResetCancelConn (void)
static void	handle_sigint (SIGNAL_ARGS)
void	setup_cancel_handler (void)

Variables
static PGcancel *volatile	cancelConn = NULL
bool	CancelRequested = false

Macro Definition Documentation

PG_NOLETTER

#define PG_NOLETTER   gettext_noop("n")

Definition at line 379 of file common.c.

Referenced by yesno_prompt().

PG_YESLETTER

#define PG_YESLETTER   gettext_noop("y")

Definition at line 377 of file common.c.

Referenced by yesno_prompt().

Function Documentation

appendQualifiedRelation()

void appendQualifiedRelation	(	PQExpBuffer	buf,
		const char *	spec,
		PGconn *	conn,
		const char *	progname,
		bool	echo
	)

Definition at line 305 of file common.c.

References ALWAYS_SECURE_SEARCH_PATH_SQL, appendPQExpBufferStr(), appendStringLiteralConn(), PQExpBufferData::data, executeCommand(), executeQuery(), fmtQualifiedId(), initPQExpBuffer(), ngettext, pg_free(), PQclear(), PQclientEncoding(), PQfinish(), PQgetvalue(), PQntuples(), PQserverVersion(), split_table_columns_spec(), and termPQExpBuffer().

Referenced by cluster_one_database(), prepare_vacuum_command(), and reindex_one_database().

{
    char       *table;
    const char *columns;
    PQExpBufferData sql;
    PGresult   *res;
    int         ntups;

    /* Before 7.3, the concept of qualifying a name did not exist. */
    if (PQserverVersion(conn) < 70300)
    {
        appendPQExpBufferStr(&sql, spec);
        return;
    }

    split_table_columns_spec(spec, PQclientEncoding(conn), &table, &columns);

    /*
     * Query must remain ABSOLUTELY devoid of unqualified names.  This would
     * be unnecessary given a regclassin() variant taking a search_path
     * argument.
     */
    initPQExpBuffer(&sql);
    appendPQExpBufferStr(&sql,
                         "SELECT c.relname, ns.nspname\n"
                         " FROM pg_catalog.pg_class c,"
                         " pg_catalog.pg_namespace ns\n"
                         " WHERE c.relnamespace OPERATOR(pg_catalog.=) ns.oid\n"
                         "  AND c.oid OPERATOR(pg_catalog.=) ");
    appendStringLiteralConn(&sql, table, conn);
    appendPQExpBufferStr(&sql, "::pg_catalog.regclass;");

    executeCommand(conn, "RESET search_path", progname, echo);

    /*
     * One row is a typical result, as is a nonexistent relation ERROR.
     * regclassin() unconditionally accepts all-digits input as an OID; if no
     * relation has that OID; this query returns no rows.  Catalog corruption
     * might elicit other row counts.
     */
    res = executeQuery(conn, sql.data, progname, echo);
    ntups = PQntuples(res);
    if (ntups != 1)
    {
        fprintf(stderr,
                ngettext("%s: query returned %d row instead of one: %s\n",
                         "%s: query returned %d rows instead of one: %s\n",
                         ntups),
                progname, ntups, sql.data);
        PQfinish(conn);
        exit(1);
    }
    appendPQExpBufferStr(buf,
                         fmtQualifiedId(PQserverVersion(conn),
                                        PQgetvalue(res, 0, 1),
                                        PQgetvalue(res, 0, 0)));
    appendPQExpBufferStr(buf, columns);
    PQclear(res);
    termPQExpBuffer(&sql);
    pg_free(table);

    PQclear(executeQuery(conn, ALWAYS_SECURE_SEARCH_PATH_SQL,
                         progname, echo));
}

connectDatabase()

PGconn* connectDatabase	(	const char *	dbname,
		const char *	pghost,
		const char *	pgport,
		const char *	pguser,
		enum trivalue	prompt_password,
		const char *	progname,
		bool	echo,
		bool	fail_ok,
		bool	allow_password_reuse
	)

Definition at line 68 of file common.c.

References _, ALWAYS_SECURE_SEARCH_PATH_SQL, conn, CONNECTION_BAD, dbname, executeQuery(), have_password, password, pghost, pgport, PQclear(), PQconnectdbParams(), PQconnectionNeedsPassword(), PQerrorMessage(), PQfinish(), PQserverVersion(), PQstatus(), progname, simple_prompt(), TRI_NO, TRI_YES, and values.

Referenced by connectMaintenanceDatabase().

{
    PGconn     *conn;
    bool        new_pass;
    static bool have_password = false;
    static char password[100];

    if (!allow_password_reuse)
        have_password = false;

    if (!have_password && prompt_password == TRI_YES)
    {
        simple_prompt("Password: ", password, sizeof(password), false);
        have_password = true;
    }

    /*
     * Start the connection.  Loop until we have a password if requested by
     * backend.
     */
    do
    {
        const char *keywords[7];
        const char *values[7];

        keywords[0] = "host";
        values[0] = pghost;
        keywords[1] = "port";
        values[1] = pgport;
        keywords[2] = "user";
        values[2] = pguser;
        keywords[3] = "password";
        values[3] = have_password ? password : NULL;
        keywords[4] = "dbname";
        values[4] = dbname;
        keywords[5] = "fallback_application_name";
        values[5] = progname;
        keywords[6] = NULL;
        values[6] = NULL;

        new_pass = false;
        conn = PQconnectdbParams(keywords, values, true);

        if (!conn)
        {
            fprintf(stderr, _("%s: could not connect to database %s: out of memory\n"),
                    progname, dbname);
            exit(1);
        }

        /*
         * No luck?  Trying asking (again) for a password.
         */
        if (PQstatus(conn) == CONNECTION_BAD &&
            PQconnectionNeedsPassword(conn) &&
            prompt_password != TRI_NO)
        {
            PQfinish(conn);
            simple_prompt("Password: ", password, sizeof(password), false);
            have_password = true;
            new_pass = true;
        }
    } while (new_pass);

    /* check to see that the backend connection was successfully made */
    if (PQstatus(conn) == CONNECTION_BAD)
    {
        if (fail_ok)
        {
            PQfinish(conn);
            return NULL;
        }
        fprintf(stderr, _("%s: could not connect to database %s: %s"),
                progname, dbname, PQerrorMessage(conn));
        exit(1);
    }

    if (PQserverVersion(conn) >= 70300)
        PQclear(executeQuery(conn, ALWAYS_SECURE_SEARCH_PATH_SQL,
                             progname, echo));

    return conn;
}

connectMaintenanceDatabase()

PGconn* connectMaintenanceDatabase	(	const char *	maintenance_db,
		const char *	pghost,
		const char *	pgport,
		const char *	pguser,
		enum trivalue	prompt_password,
		const char *	progname,
		bool	echo
	)

Definition at line 159 of file common.c.

References conn, and connectDatabase().

Referenced by cluster_all_databases(), main(), reindex_all_databases(), and vacuum_all_databases().

{
    PGconn     *conn;

    /* If a maintenance database name was specified, just connect to it. */
    if (maintenance_db)
        return connectDatabase(maintenance_db, pghost, pgport, pguser,
                               prompt_password, progname, echo, false, false);

    /* Otherwise, try postgres first and then template1. */
    conn = connectDatabase("postgres", pghost, pgport, pguser, prompt_password,
                           progname, echo, true, false);
    if (!conn)
        conn = connectDatabase("template1", pghost, pgport, pguser,
                               prompt_password, progname, echo, false, false);

    return conn;
}

executeCommand()

void executeCommand	(	PGconn *	conn,
		const char *	query,
		const char *	progname,
		bool	echo
	)

Definition at line 212 of file common.c.

References _, PGRES_COMMAND_OK, PQclear(), PQerrorMessage(), PQexec(), PQfinish(), and PQresultStatus().

Referenced by appendQualifiedRelation().

{
    PGresult   *res;

    if (echo)
        printf("%s\n", query);

    res = PQexec(conn, query);
    if (!res ||
        PQresultStatus(res) != PGRES_COMMAND_OK)
    {
        fprintf(stderr, _("%s: query failed: %s"),
                progname, PQerrorMessage(conn));
        fprintf(stderr, _("%s: query was: %s\n"),
                progname, query);
        PQfinish(conn);
        exit(1);
    }

    PQclear(res);
}

executeMaintenanceCommand()

bool executeMaintenanceCommand	(	PGconn *	conn,
		const char *	query,
		bool	echo
	)

Definition at line 242 of file common.c.

References PGRES_COMMAND_OK, PQclear(), PQexec(), PQresultStatus(), ResetCancelConn(), and SetCancelConn().

Referenced by cluster_one_database(), reindex_one_database(), reindex_system_catalogs(), and run_vacuum_command().

{
    PGresult   *res;
    bool        r;

    if (echo)
        printf("%s\n", query);

    SetCancelConn(conn);
    res = PQexec(conn, query);
    ResetCancelConn();

    r = (res && PQresultStatus(res) == PGRES_COMMAND_OK);

    if (res)
        PQclear(res);

    return r;
}

executeQuery()

PGresult* executeQuery	(	PGconn *	conn,
		const char *	query,
		const char *	progname,
		bool	echo
	)

Definition at line 185 of file common.c.

References _, PGRES_TUPLES_OK, PQerrorMessage(), PQexec(), PQfinish(), and PQresultStatus().

Referenced by appendQualifiedRelation(), and connectDatabase().

{
    PGresult   *res;

    if (echo)
        printf("%s\n", query);

    res = PQexec(conn, query);
    if (!res ||
        PQresultStatus(res) != PGRES_TUPLES_OK)
    {
        fprintf(stderr, _("%s: query failed: %s"),
                progname, PQerrorMessage(conn));
        fprintf(stderr, _("%s: query was: %s\n"),
                progname, query);
        PQfinish(conn);
        exit(1);
    }

    return res;
}

handle_help_version_opts()

void handle_help_version_opts	(	int	argc,
		char *	argv[],
		const char *	fixed_progname,
		help_handler	hlp
	)

Definition at line 37 of file common.c.

References get_progname().

Referenced by main().

{
    if (argc > 1)
    {
        if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
        {
            hlp(get_progname(argv[0]));
            exit(0);
        }
        if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
        {
            printf("%s (PostgreSQL) " PG_VERSION "\n", fixed_progname);
            exit(0);
        }
    }
}

handle_sigint()

static void handle_sigint ( SIGNAL_ARGS  )

static

Definition at line 471 of file common.c.

References _, CancelRequested, and PQcancel().

Referenced by setup_cancel_handler().

{
    int         save_errno = errno;
    char        errbuf[256];

    /* Send QueryCancel if we are processing a database query */
    if (cancelConn != NULL)
    {
        if (PQcancel(cancelConn, errbuf, sizeof(errbuf)))
        {
            CancelRequested = true;
            fprintf(stderr, _("Cancel request sent\n"));
        }
        else
            fprintf(stderr, _("Could not send cancel request: %s"), errbuf);
    }
    else
        CancelRequested = true;

    errno = save_errno;         /* just in case the write changed it */
}

ResetCancelConn()

void ResetCancelConn

(

void

)

Definition at line 444 of file common.c.

References cancelConn, and PQfreeCancel().

{
    PGcancel   *oldCancelConn;

#ifdef WIN32
    EnterCriticalSection(&cancelConnLock);
#endif

    oldCancelConn = cancelConn;

    /* be sure handle_sigint doesn't use pointer while freeing */
    cancelConn = NULL;

    if (oldCancelConn != NULL)
        PQfreeCancel(oldCancelConn);

#ifdef WIN32
    LeaveCriticalSection(&cancelConnLock);
#endif
}

SetCancelConn()

void SetCancelConn

(

PGconn *

conn

)

Definition at line 414 of file common.c.

References cancelConn, PQfreeCancel(), and PQgetCancel().

{
    PGcancel   *oldCancelConn;

#ifdef WIN32
    EnterCriticalSection(&cancelConnLock);
#endif

    /* Free the old one if we have one */
    oldCancelConn = cancelConn;

    /* be sure handle_sigint doesn't use pointer while freeing */
    cancelConn = NULL;

    if (oldCancelConn != NULL)
        PQfreeCancel(oldCancelConn);

    cancelConn = PQgetCancel(conn);

#ifdef WIN32
    LeaveCriticalSection(&cancelConnLock);
#endif
}

setup_cancel_handler()

void setup_cancel_handler

(

void

)

Definition at line 494 of file common.c.

References _, cancel_pressed, CancelRequested, FALSE, handle_sigint(), PQcancel(), pqsignal(), setup_cancel_handler(), TRUE, and write_stderr.

{
    pqsignal(SIGINT, handle_sigint);
}

split_table_columns_spec()

static void split_table_columns_spec ( const char *  spec, int  encoding, char **  table, const char **  columns  )

static

Definition at line 269 of file common.c.

References pg_strdup(), and PQmblen().

Referenced by appendQualifiedRelation().

{
    bool        inquotes = false;
    const char *cp = spec;

    /*
     * Find the first '(' not identifier-quoted.  Based on
     * dequote_downcase_identifier().
     */
    while (*cp && (*cp != '(' || inquotes))
    {
        if (*cp == '"')
        {
            if (inquotes && cp[1] == '"')
                cp++;           /* pair does not affect quoting */
            else
                inquotes = !inquotes;
            cp++;
        }
        else
            cp += PQmblen(cp, encoding);
    }
    *table = pg_strdup(spec);
    (*table)[cp - spec] = '\0'; /* no strndup */
    *columns = cp;
}

yesno_prompt()

bool yesno_prompt

(

const char *

question

)

Definition at line 382 of file common.c.

References _, PG_NOLETTER, PG_YESLETTER, simple_prompt(), and snprintf().

Referenced by main().

{
    char        prompt[256];

    /*------
       translator: This is a question followed by the translated options for
       "yes" and "no". */
    snprintf(prompt, sizeof(prompt), _("%s (%s/%s) "),
             _(question), _(PG_YESLETTER), _(PG_NOLETTER));

    for (;;)
    {
        char        resp[10];

        simple_prompt(prompt, resp, sizeof(resp), true);

        if (strcmp(resp, _(PG_YESLETTER)) == 0)
            return true;
        if (strcmp(resp, _(PG_NOLETTER)) == 0)
            return false;

        printf(_("Please answer \"%s\" or \"%s\".\n"),
               _(PG_YESLETTER), _(PG_NOLETTER));
    }
}

Variable Documentation

cancelConn

PGcancel* volatile cancelConn = NULL

static

Definition at line 25 of file common.c.

Referenced by ResetCancelConn(), and SetCancelConn().

CancelRequested

bool CancelRequested = false

Definition at line 26 of file common.c.

Referenced by handle_sigint(), select_loop(), setup_cancel_handler(), and vacuum_one_database().