Fix a series of typos and outdated references

Author: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/c1d63754-cb85-2d8a-8409-bde2c4d2d04b@gmail.com

src/backend/access/transam/xlogreader.c

@@ -946,9 +946,9 @@ err:
 	XLogReaderInvalReadState(state);
 
 	/*
-	 * If an error was written to errmsg_buf, it'll be returned to the caller
-	 * of XLogReadRecord() after all successfully decoded records from the
-	 * read queue.
+	 * If an error was written to errormsg_buf, it'll be returned to the
+	 * caller of XLogReadRecord() after all successfully decoded records from
+	 * the read queue.
 	 */
 
 	return XLREAD_FAIL;

src/backend/executor/execCurrent.c

@@ -200,7 +200,7 @@ execCurrentOf(CurrentOfExpr *cexpr,
 			/*
 			 * For IndexOnlyScan, the tuple stored in ss_ScanTupleSlot may be
 			 * a virtual tuple that does not have the ctid column, so we have
-			 * to get the TID from xs_ctup.t_self.
+			 * to get the TID from xs_heaptid.
 			 */
 			IndexScanDesc scan = ((IndexOnlyScanState *) scanstate)->ioss_ScanDesc;
 

src/backend/utils/activity/pgstat_shmem.c

@@ -80,7 +80,7 @@ static const dshash_parameters dsh_params = {
  * compares to their copy of pgStatSharedRefAge on a regular basis.
  */
 static pgstat_entry_ref_hash_hash *pgStatEntryRefHash = NULL;
-static int	pgStatSharedRefAge = 0; /* cache age of pgStatShmLookupCache */
+static int	pgStatSharedRefAge = 0; /* cache age of pgStatLocal.shmem */
 
 /*
  * Memory contexts containing the pgStatEntryRefHash table and the
@@ -887,7 +887,7 @@ pgstat_drop_database_and_contents(Oid dboid)
 
 	/*
 	 * If some of the stats data could not be freed, signal the reference
-	 * holders to run garbage collection of their cached pgStatShmLookupCache.
+	 * holders to run garbage collection of their cached pgStatLocal.shmem.
 	 */
 	if (not_freed_count > 0)
 		pgstat_request_entry_refs_gc();

src/include/access/sdir.h

@@ -17,9 +17,9 @@
 
 /*
  * Defines the direction for scanning a table or an index.  Scans are never
- * invoked using NoMovementScanDirectionScans.  For convenience, we use the
- * values -1 and 1 for backward and forward scans.  This allows us to perform
- * a few mathematical tricks such as what is done in ScanDirectionCombine.
+ * invoked using NoMovementScanDirection.  For convenience, we use the values
+ * -1 and 1 for backward and forward scans.  This allows us to perform a few
+ * mathematical tricks such as what is done in ScanDirectionCombine.
  */
 typedef enum ScanDirection
 {

src/include/access/xlogreader.h

@@ -224,9 +224,9 @@ struct XLogReaderState
 	 * should not be accessed directly.
 	 * ----------------------------------------
 	 * Start and end point of the last record read and decoded by
-	 * XLogReadRecordInternal().  NextRecPtr is also used as the position to
-	 * decode next.  Calling XLogBeginRead() sets NextRecPtr and EndRecPtr to
-	 * the requested starting position.
+	 * XLogReadRecord().  NextRecPtr is also used as the position to decode
+	 * next.  Calling XLogBeginRead() sets NextRecPtr and EndRecPtr to the
+	 * requested starting position.
 	 */
 	XLogRecPtr	DecodeRecPtr;	/* start of last record decoded */
 	XLogRecPtr	NextRecPtr;		/* end+1 of last record decoded */

src/test/modules/worker_spi/worker_spi.c

@@ -174,9 +174,10 @@ worker_spi_main(Datum main_arg)
 											 worker_spi_role, flags);
 
 	/*
-	 * Disable parallel query for workers started with BYPASS_ALLOWCONN or
-	 * BGWORKER_BYPASS_ALLOWCONN so as these don't attempt connections using a
-	 * database or a role that may not allow that.
+	 * Disable parallel query for workers started with
+	 * BGWORKER_BYPASS_ALLOWCONN or BGWORKER_BYPASS_ROLELOGINCHECK so as these
+	 * don't attempt connections using a database or a role that may not allow
+	 * that.
 	 */
 	if ((flags & (BGWORKER_BYPASS_ALLOWCONN | BGWORKER_BYPASS_ROLELOGINCHECK)))
 		SetConfigOption("max_parallel_workers_per_gather", "0",