[Issue #143] review feedback implementation

src/catalog.c

@@ -615,7 +615,7 @@ catalog_get_last_data_backup(parray *backup_list, TimeLineID tli, time_t current
 			switch (scan_parent_chain(backup, &tmp_backup))
 			{
 				/* broken chain */
-				case 0:
+				case ChainIsBroken:
 					invalid_backup_id = base36enc_dup(tmp_backup->parent_backup);
 
 					elog(WARNING, "Backup %s has missing parent: %s. Cannot be a parent",
@@ -624,7 +624,7 @@ catalog_get_last_data_backup(parray *backup_list, TimeLineID tli, time_t current
 					continue;
 
 				/* chain is intact, but at least one parent is invalid */
-				case 1:
+				case ChainIsInvalid:
 					invalid_backup_id = base36enc_dup(tmp_backup->start_time);
 
 					elog(WARNING, "Backup %s has invalid parent: %s. Cannot be a parent",
@@ -633,7 +633,7 @@ catalog_get_last_data_backup(parray *backup_list, TimeLineID tli, time_t current
 					continue;
 
 				/* chain is ok */
-				case 2:
+				case ChainIsOk:
 					/* Yes, we could call is_parent() earlier - after choosing the ancestor,
 					 * but this way we have an opportunity to detect and report all possible
 					 * anomalies.
@@ -755,13 +755,14 @@ get_multi_timeline_parent(parray *backup_list, parray *tli_list,
 	/* Optimistically, look on current timeline for valid incremental backup, child of ancestor */
 	if (my_tlinfo->backups)
 	{
+		/* backups are sorted in descending order and we need latest valid */
 		for (i = 0; i < parray_num(my_tlinfo->backups); i++)
 		{
 			pgBackup *tmp_backup = NULL;
 			pgBackup *backup = (pgBackup *) parray_get(my_tlinfo->backups, i);
 
 			/* found suitable parent */
-			if (scan_parent_chain(backup, &tmp_backup) == 2 &&
+			if (scan_parent_chain(backup, &tmp_backup) == ChainIsOk &&
 				is_parent(ancestor_backup->start_time, backup, false))
 				return backup;
 		}
@@ -786,7 +787,7 @@ get_multi_timeline_parent(parray *backup_list, parray *tli_list,
 				if (backup->stop_lsn > tmp_tlinfo->switchpoint)
 					continue;
 
-				if (scan_parent_chain(backup, &tmp_backup) == 2 &&
+				if (scan_parent_chain(backup, &tmp_backup) == ChainIsOk &&
 					is_parent(ancestor_backup->start_time, backup, true))
 					return backup;
 			}
@@ -2382,18 +2383,18 @@ scan_parent_chain(pgBackup *current_backup, pgBackup **result_backup)
 	{
 		/* Set oldest child backup in chain */
 		*result_backup = target_backup;
-		return 0;
+		return ChainIsBroken;
 	}
 
 	/* chain is ok, but some backups are invalid */
 	if (invalid_backup)
 	{
 		*result_backup = invalid_backup;
-		return 1;
+		return ChainIsInvalid;
 	}
 
 	*result_backup = target_backup;
-	return 2;
+	return ChainIsOk;
 }
 
 /*

src/parsexlog.c

@@ -859,23 +859,23 @@ SimpleXLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr,
 		char		xlogfname[MAXFNAMELEN];
 		char		partial_file[MAXPGPATH];
 
-		GetXLogFileName(xlogfname, reader_data->tli, reader_data->xlogsegno,
-						wal_seg_size);
-		snprintf(reader_data->xlogpath, MAXPGPATH, "%s/%s", wal_archivedir,
-				 xlogfname);
-		snprintf(partial_file, MAXPGPATH, "%s/%s.partial", wal_archivedir,
-					xlogfname);
-		snprintf(reader_data->gz_xlogpath, sizeof(reader_data->gz_xlogpath),
-					 "%s.gz", reader_data->xlogpath);
+		GetXLogFileName(xlogfname, reader_data->tli, reader_data->xlogsegno, wal_seg_size);
+
+		snprintf(reader_data->xlogpath, MAXPGPATH, "%s/%s", wal_archivedir, xlogfname);
+		snprintf(reader_data->gz_xlogpath, MAXPGPATH, "%s.gz", reader_data->xlogpath);
+
+		/* We fall back to using .partial segment in case if we are running
+		 * multi-timeline incremental backup right after standby promotion.
+		 * TODO: it should be explicitly enabled.
+		 */
+		snprintf(partial_file, MAXPGPATH, "%s.partial", reader_data->xlogpath);
 
 		/* If segment do not exists, but the same
 		 * segment with '.partial' suffix does, use it instead */
 		if (!fileExists(reader_data->xlogpath, FIO_BACKUP_HOST) &&
 			fileExists(partial_file, FIO_BACKUP_HOST))
 		{
-			snprintf(reader_data->xlogpath, MAXPGPATH, "%s/%s.partial", wal_archivedir,
-				 xlogfname);
-			strncpy(reader_data->xlogpath, partial_file, MAXPGPATH);
+			snprintf(reader_data->xlogpath, MAXPGPATH, "%s", partial_file);
 		}
 
 		if (fileExists(reader_data->xlogpath, FIO_BACKUP_HOST))

src/pg_probackup.h

@@ -800,6 +800,11 @@ extern int pgBackupCompareIdEqual(const void *l, const void *r);
 
 extern pgBackup* find_parent_full_backup(pgBackup *current_backup);
 extern int scan_parent_chain(pgBackup *current_backup, pgBackup **result_backup);
+/* return codes for scan_parent_chain */
+#define ChainIsBroken 0
+#define ChainIsInvalid 1
+#define ChainIsOk 2
+
 extern bool is_parent(time_t parent_backup_time, pgBackup *child_backup, bool inclusive);
 extern bool is_prolific(parray *backup_list, pgBackup *target_backup);
 extern bool in_backup_list(parray *backup_list, pgBackup *target_backup);

src/restore.c

@@ -251,7 +251,7 @@ do_restore_or_validate(time_t target_backup_id, pgRecoveryTarget *rt,
 
 		result = scan_parent_chain(dest_backup, &tmp_backup);
 
-		if (result == 0)
+		if (result == ChainIsBroken)
 		{
 			/* chain is broken, determine missing backup ID
 			 * and orphinize all his descendants
@@ -290,7 +290,7 @@ do_restore_or_validate(time_t target_backup_id, pgRecoveryTarget *rt,
 			/* No point in doing futher */
 			elog(ERROR, "%s of backup %s failed.", action, base36enc(dest_backup->start_time));
 		}
-		else if (result == 1)
+		else if (result == ChainIsInvalid)
 		{
 			/* chain is intact, but at least one parent is invalid */
 			set_orphan_status(backups, tmp_backup);

src/validate.c

@@ -479,7 +479,7 @@ do_validate_instance(void)
 			result = scan_parent_chain(current_backup, &tmp_backup);
 
 			/* chain is broken */
-			if (result == 0)
+			if (result == ChainIsBroken)
 			{
 				char	   *parent_backup_id;
 				/* determine missing backup ID */
@@ -505,7 +505,7 @@ do_validate_instance(void)
 				continue;
 			}
 			/* chain is whole, but at least one parent is invalid */
-			else if (result == 1)
+			else if (result == ChainIsInvalid)
 			{
 				/* Oldest corrupt backup has a chance for revalidation */
 				if (current_backup->start_time != tmp_backup->start_time)
@@ -630,7 +630,7 @@ do_validate_instance(void)
 					 */
 					result = scan_parent_chain(backup, &tmp_backup);
 
-					if (result == 1)
+					if (result == ChainIsInvalid)
 					{
 						/* revalidation make sense only if oldest invalid backup is current_backup
 						 */

tests/page.py

@@ -819,7 +819,7 @@ class PageTest(ProbackupTest, unittest.TestCase):
         self.backup_node(backup_dir, 'node', node)
 
         # make some wals
-        node.pgbench_init(scale=4)
+        node.pgbench_init(scale=10)
 
         # delete last wal segment
         wals_dir = os.path.join(backup_dir, 'wal', 'node')

tests/validate.py

@@ -1786,7 +1786,7 @@ class ValidateTest(ProbackupTest, unittest.TestCase):
             self.assertTrue(
                 'LOG:  archive command failed with exit code 1' in log_content and
                 'DETAIL:  The failed archive command was:' in log_content and
-                'INFO: pg_probackup archive-push from' in log_content,
+                'WAL file already exists in archive with different checksum' in log_content,
                 'Expecting error messages about failed archive_command'
             )
             self.assertFalse(