/*-------------------------------------------------------------------------

 *

 * pg_controldata.c

 *

 * Routines to expose the contents of the control data file via

 * a set of SQL functions.

 *

 * Portions Copyright (c) 1996-2025, 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 "common/controldata_utils.h"

#include "funcapi.h"

#include "miscadmin.h"

#include "storage/lwlock.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;

  if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)

    elog(ERROR, "return type must be a row type");

  /* read the control file */

  LWLockAcquire(ControlFileLock, LW_SHARED);

  ControlFile = get_controlfile(DataDir, &crc_ok);

  LWLockRelease(ControlFileLock);

  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[18];

  bool    nulls[18];

  TupleDesc tupdesc;

  HeapTuple htup;

  ControlFileData *ControlFile;

  XLogSegNo segno;

  char    xlogfilename[MAXFNAMELEN];

  bool    crc_ok;

  if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)

    elog(ERROR, "return type must be a row type");

  /* Read the control file. */

  LWLockAcquire(ControlFileLock, LW_SHARED);

  ControlFile = get_controlfile(DataDir, &crc_ok);

  LWLockRelease(ControlFileLock);

  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.nextXid),

                       XidFromFullTransactionId(ControlFile->checkPointCopy.nextXid)));

  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;

  if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)

    elog(ERROR, "return type must be a row type");

  /* read the control file */

  LWLockAcquire(ControlFileLock, LW_SHARED);

  ControlFile = get_controlfile(DataDir, &crc_ok);

  LWLockRelease(ControlFileLock);

  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[12];

  bool    nulls[12];

  TupleDesc tupdesc;

  HeapTuple htup;

  ControlFileData *ControlFile;

  bool    crc_ok;

  if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)

    elog(ERROR, "return type must be a row type");

  /* read the control file */

  LWLockAcquire(ControlFileLock, LW_SHARED);

  ControlFile = get_controlfile(DataDir, &crc_ok);

  LWLockRelease(ControlFileLock);

  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;

  values[11] = BoolGetDatum(ControlFile->default_char_signedness);

  nulls[11] = false;

  htup = heap_form_tuple(tupdesc, values, nulls);

  PG_RETURN_DATUM(HeapTupleGetDatum(htup));

}