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

 *

 * pgstat_archiver.c

 *    Implementation of archiver statistics.

 *

 * This file contains the implementation of archiver statistics. It is kept

 * separate from pgstat.c to enforce the line between the statistics access /

 * storage implementation and the details about individual types of

 * statistics.

 *

 * Copyright (c) 2001-2025, PostgreSQL Global Development Group

 *

 * IDENTIFICATION

 *    src/backend/utils/activity/pgstat_archiver.c

 * -------------------------------------------------------------------------

 */

#include "postgres.h"

#include "utils/pgstat_internal.h"

#include "utils/timestamp.h"

/*

 * Report archiver statistics

 */

void

pgstat_report_archiver(const char *xlog, bool failed)

{

  PgStatShared_Archiver *stats_shmem = &pgStatLocal.shmem->archiver;

  TimestampTz now = GetCurrentTimestamp();

  pgstat_begin_changecount_write(&stats_shmem->changecount);

  if (failed)

  {

    ++stats_shmem->stats.failed_count;

    memcpy(&stats_shmem->stats.last_failed_wal, xlog,

         sizeof(stats_shmem->stats.last_failed_wal));

    stats_shmem->stats.last_failed_timestamp = now;

  }

  else

  {

    ++stats_shmem->stats.archived_count;

    memcpy(&stats_shmem->stats.last_archived_wal, xlog,

         sizeof(stats_shmem->stats.last_archived_wal));

    stats_shmem->stats.last_archived_timestamp = now;

  }

  pgstat_end_changecount_write(&stats_shmem->changecount);

}

/*

 * Support function for the SQL-callable pgstat* functions. Returns

 * a pointer to the archiver statistics struct.

 */

PgStat_ArchiverStats *

pgstat_fetch_stat_archiver(void)

{

  pgstat_snapshot_fixed(PGSTAT_KIND_ARCHIVER);

  return &pgStatLocal.snapshot.archiver;

}

void

pgstat_archiver_init_shmem_cb(void *stats)

{

  PgStatShared_Archiver *stats_shmem = (PgStatShared_Archiver *) stats;

  LWLockInitialize(&stats_shmem->lock, LWTRANCHE_PGSTATS_DATA);

}

void

pgstat_archiver_reset_all_cb(TimestampTz ts)

{

  PgStatShared_Archiver *stats_shmem = &pgStatLocal.shmem->archiver;

  /* see explanation above PgStatShared_Archiver for the reset protocol */

  LWLockAcquire(&stats_shmem->lock, LW_EXCLUSIVE);

  pgstat_copy_changecounted_stats(&stats_shmem->reset_offset,

                  &stats_shmem->stats,

                  sizeof(stats_shmem->stats),

                  &stats_shmem->changecount);

  stats_shmem->stats.stat_reset_timestamp = ts;

  LWLockRelease(&stats_shmem->lock);

}

void

pgstat_archiver_snapshot_cb(void)

{

  PgStatShared_Archiver *stats_shmem = &pgStatLocal.shmem->archiver;

  PgStat_ArchiverStats *stat_snap = &pgStatLocal.snapshot.archiver;

  PgStat_ArchiverStats *reset_offset = &stats_shmem->reset_offset;

  PgStat_ArchiverStats reset;

  pgstat_copy_changecounted_stats(stat_snap,

                  &stats_shmem->stats,

                  sizeof(stats_shmem->stats),

                  &stats_shmem->changecount);

  LWLockAcquire(&stats_shmem->lock, LW_SHARED);

  memcpy(&reset, reset_offset, sizeof(stats_shmem->stats));

  LWLockRelease(&stats_shmem->lock);

  /* compensate by reset offsets */

  if (stat_snap->archived_count == reset.archived_count)

  {

    stat_snap->last_archived_wal[0] = 0;

    stat_snap->last_archived_timestamp = 0;

  }

  stat_snap->archived_count -= reset.archived_count;

  if (stat_snap->failed_count == reset.failed_count)

  {

    stat_snap->last_failed_wal[0] = 0;

    stat_snap->last_failed_timestamp = 0;

  }

  stat_snap->failed_count -= reset.failed_count;

}