pg_controldata.c

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/*-------------------------------------------------------------------------
 *
 * pg_controldata.c
 *
 * Routines to expose the contents of the control data file via
 * a set of SQL functions.
 *
 * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * IDENTIFICATION
 *    src/backend/utils/misc/pg_controldata.c
 *-------------------------------------------------------------------------
 */

#include "postgres.h"

#include "access/htup_details.h"
#include "access/transam.h"
#include "access/xlog.h"
#include "access/xlog_internal.h"
#include "catalog/pg_control.h"
#include "catalog/pg_type.h"
#include "common/controldata_utils.h"
#include "funcapi.h"
#include "miscadmin.h"
#include "utils/builtins.h"
#include "utils/pg_lsn.h"
#include "utils/timestamp.h"

Datum
pg_control_system(PG_FUNCTION_ARGS)
{
    Datum       values[4];
    bool        nulls[4];
    TupleDesc   tupdesc;
    HeapTuple   htup;
    ControlFileData *ControlFile;
    bool        crc_ok;

    /*
     * Construct a tuple descriptor for the result row.  This must match this
     * function's pg_proc entry!
     */
    tupdesc = CreateTemplateTupleDesc(4);
    TupleDescInitEntry(tupdesc, (AttrNumber) 1, "pg_control_version",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 2, "catalog_version_no",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 3, "system_identifier",
                       INT8OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 4, "pg_control_last_modified",
                       TIMESTAMPTZOID, -1, 0);
    tupdesc = BlessTupleDesc(tupdesc);

    /* read the control file */
    ControlFile = get_controlfile(DataDir, &crc_ok);
    if (!crc_ok)
        ereport(ERROR,
                (errmsg("calculated CRC checksum does not match value stored in file")));

    values[0] = Int32GetDatum(ControlFile->pg_control_version);
    nulls[0] = false;

    values[1] = Int32GetDatum(ControlFile->catalog_version_no);
    nulls[1] = false;

    values[2] = Int64GetDatum(ControlFile->system_identifier);
    nulls[2] = false;

    values[3] = TimestampTzGetDatum(time_t_to_timestamptz(ControlFile->time));
    nulls[3] = false;

    htup = heap_form_tuple(tupdesc, values, nulls);

    PG_RETURN_DATUM(HeapTupleGetDatum(htup));
}

Datum
pg_control_checkpoint(PG_FUNCTION_ARGS)
{
    Datum       values[19];
    bool        nulls[19];
    TupleDesc   tupdesc;
    HeapTuple   htup;
    ControlFileData *ControlFile;
    XLogSegNo   segno;
    char        xlogfilename[MAXFNAMELEN];
    bool        crc_ok;

    /*
     * Construct a tuple descriptor for the result row.  This must match this
     * function's pg_proc entry!
     */
    tupdesc = CreateTemplateTupleDesc(18);
    TupleDescInitEntry(tupdesc, (AttrNumber) 1, "checkpoint_lsn",
                       LSNOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 2, "redo_lsn",
                       LSNOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 3, "redo_wal_file",
                       TEXTOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 4, "timeline_id",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 5, "prev_timeline_id",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 6, "full_page_writes",
                       BOOLOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 7, "next_xid",
                       TEXTOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 8, "next_oid",
                       OIDOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 9, "next_multixact_id",
                       XIDOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 10, "next_multi_offset",
                       XIDOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 11, "oldest_xid",
                       XIDOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 12, "oldest_xid_dbid",
                       OIDOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 13, "oldest_active_xid",
                       XIDOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 14, "oldest_multi_xid",
                       XIDOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 15, "oldest_multi_dbid",
                       OIDOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 16, "oldest_commit_ts_xid",
                       XIDOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 17, "newest_commit_ts_xid",
                       XIDOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 18, "checkpoint_time",
                       TIMESTAMPTZOID, -1, 0);
    tupdesc = BlessTupleDesc(tupdesc);

    /* Read the control file. */
    ControlFile = get_controlfile(DataDir, &crc_ok);
    if (!crc_ok)
        ereport(ERROR,
                (errmsg("calculated CRC checksum does not match value stored in file")));

    /*
     * Calculate name of the WAL file containing the latest checkpoint's REDO
     * start point.
     */
    XLByteToSeg(ControlFile->checkPointCopy.redo, segno, wal_segment_size);
    XLogFileName(xlogfilename, ControlFile->checkPointCopy.ThisTimeLineID,
                 segno, wal_segment_size);

    /* Populate the values and null arrays */
    values[0] = LSNGetDatum(ControlFile->checkPoint);
    nulls[0] = false;

    values[1] = LSNGetDatum(ControlFile->checkPointCopy.redo);
    nulls[1] = false;

    values[2] = CStringGetTextDatum(xlogfilename);
    nulls[2] = false;

    values[3] = Int32GetDatum(ControlFile->checkPointCopy.ThisTimeLineID);
    nulls[3] = false;

    values[4] = Int32GetDatum(ControlFile->checkPointCopy.PrevTimeLineID);
    nulls[4] = false;

    values[5] = BoolGetDatum(ControlFile->checkPointCopy.fullPageWrites);
    nulls[5] = false;

    values[6] = CStringGetTextDatum(psprintf("%u:%u",
                                             EpochFromFullTransactionId(ControlFile->checkPointCopy.nextFullXid),
                                             XidFromFullTransactionId(ControlFile->checkPointCopy.nextFullXid)));
    nulls[6] = false;

    values[7] = ObjectIdGetDatum(ControlFile->checkPointCopy.nextOid);
    nulls[7] = false;

    values[8] = TransactionIdGetDatum(ControlFile->checkPointCopy.nextMulti);
    nulls[8] = false;

    values[9] = TransactionIdGetDatum(ControlFile->checkPointCopy.nextMultiOffset);
    nulls[9] = false;

    values[10] = TransactionIdGetDatum(ControlFile->checkPointCopy.oldestXid);
    nulls[10] = false;

    values[11] = ObjectIdGetDatum(ControlFile->checkPointCopy.oldestXidDB);
    nulls[11] = false;

    values[12] = TransactionIdGetDatum(ControlFile->checkPointCopy.oldestActiveXid);
    nulls[12] = false;

    values[13] = TransactionIdGetDatum(ControlFile->checkPointCopy.oldestMulti);
    nulls[13] = false;

    values[14] = ObjectIdGetDatum(ControlFile->checkPointCopy.oldestMultiDB);
    nulls[14] = false;

    values[15] = TransactionIdGetDatum(ControlFile->checkPointCopy.oldestCommitTsXid);
    nulls[15] = false;

    values[16] = TransactionIdGetDatum(ControlFile->checkPointCopy.newestCommitTsXid);
    nulls[16] = false;

    values[17] = TimestampTzGetDatum(
                                     time_t_to_timestamptz(ControlFile->checkPointCopy.time));
    nulls[17] = false;

    htup = heap_form_tuple(tupdesc, values, nulls);

    PG_RETURN_DATUM(HeapTupleGetDatum(htup));
}

Datum
pg_control_recovery(PG_FUNCTION_ARGS)
{
    Datum       values[5];
    bool        nulls[5];
    TupleDesc   tupdesc;
    HeapTuple   htup;
    ControlFileData *ControlFile;
    bool        crc_ok;

    /*
     * Construct a tuple descriptor for the result row.  This must match this
     * function's pg_proc entry!
     */
    tupdesc = CreateTemplateTupleDesc(5);
    TupleDescInitEntry(tupdesc, (AttrNumber) 1, "min_recovery_end_lsn",
                       LSNOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 2, "min_recovery_end_timeline",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 3, "backup_start_lsn",
                       LSNOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 4, "backup_end_lsn",
                       LSNOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 5, "end_of_backup_record_required",
                       BOOLOID, -1, 0);
    tupdesc = BlessTupleDesc(tupdesc);

    /* read the control file */
    ControlFile = get_controlfile(DataDir, &crc_ok);
    if (!crc_ok)
        ereport(ERROR,
                (errmsg("calculated CRC checksum does not match value stored in file")));

    values[0] = LSNGetDatum(ControlFile->minRecoveryPoint);
    nulls[0] = false;

    values[1] = Int32GetDatum(ControlFile->minRecoveryPointTLI);
    nulls[1] = false;

    values[2] = LSNGetDatum(ControlFile->backupStartPoint);
    nulls[2] = false;

    values[3] = LSNGetDatum(ControlFile->backupEndPoint);
    nulls[3] = false;

    values[4] = BoolGetDatum(ControlFile->backupEndRequired);
    nulls[4] = false;

    htup = heap_form_tuple(tupdesc, values, nulls);

    PG_RETURN_DATUM(HeapTupleGetDatum(htup));
}

Datum
pg_control_init(PG_FUNCTION_ARGS)
{
    Datum       values[11];
    bool        nulls[11];
    TupleDesc   tupdesc;
    HeapTuple   htup;
    ControlFileData *ControlFile;
    bool        crc_ok;

    /*
     * Construct a tuple descriptor for the result row.  This must match this
     * function's pg_proc entry!
     */
    tupdesc = CreateTemplateTupleDesc(11);
    TupleDescInitEntry(tupdesc, (AttrNumber) 1, "max_data_alignment",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 2, "database_block_size",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 3, "blocks_per_segment",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 4, "wal_block_size",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 5, "bytes_per_wal_segment",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 6, "max_identifier_length",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 7, "max_index_columns",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 8, "max_toast_chunk_size",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 9, "large_object_chunk_size",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 10, "float8_pass_by_value",
                       BOOLOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 11, "data_page_checksum_version",
                       INT4OID, -1, 0);
    tupdesc = BlessTupleDesc(tupdesc);

    /* read the control file */
    ControlFile = get_controlfile(DataDir, &crc_ok);
    if (!crc_ok)
        ereport(ERROR,
                (errmsg("calculated CRC checksum does not match value stored in file")));

    values[0] = Int32GetDatum(ControlFile->maxAlign);
    nulls[0] = false;

    values[1] = Int32GetDatum(ControlFile->blcksz);
    nulls[1] = false;

    values[2] = Int32GetDatum(ControlFile->relseg_size);
    nulls[2] = false;

    values[3] = Int32GetDatum(ControlFile->xlog_blcksz);
    nulls[3] = false;

    values[4] = Int32GetDatum(ControlFile->xlog_seg_size);
    nulls[4] = false;

    values[5] = Int32GetDatum(ControlFile->nameDataLen);
    nulls[5] = false;

    values[6] = Int32GetDatum(ControlFile->indexMaxKeys);
    nulls[6] = false;

    values[7] = Int32GetDatum(ControlFile->toast_max_chunk_size);
    nulls[7] = false;

    values[8] = Int32GetDatum(ControlFile->loblksize);
    nulls[8] = false;

    values[9] = BoolGetDatum(ControlFile->float8ByVal);
    nulls[9] = false;

    values[10] = Int32GetDatum(ControlFile->data_checksum_version);
    nulls[10] = false;

    htup = heap_form_tuple(tupdesc, values, nulls);

    PG_RETURN_DATUM(HeapTupleGetDatum(htup));
}