rework file stat handling to simplify and cross-platform-ability

- don't use full `struct stat` since it differs between platforms
- store file kind separately from mode in pb specific way
- add pioFilesAreSame as replacement of fio_is_same_file since it needs
  st_ino and st_dev, therefore had to run on localdrive always.

Author: funny-falcon

src/archive.c

@@ -388,7 +388,7 @@ push_file_internal(const char *wal_file_name, const char *pg_xlog_dir,
     char to_fullpath[MAXPGPATH];
     char to_fullpath_part[MAXPGPATH];
 /* partial handling */
-    struct stat st;
+    pio_stat_t st;
     int partial_try_count = 0;
     ssize_t partial_file_size = 0;
     bool partial_is_stale = true;
@@ -466,11 +466,11 @@ push_file_internal(const char *wal_file_name, const char *pg_xlog_dir,
             elog(LOG,
                  "Temp WAL file already exists, waiting on it %u seconds: \"%s\"",
                  archive_timeout, to_fullpath_part);
-            partial_file_size = st.st_size;
+            partial_file_size = st.pst_size;
         }
 
         /* file size is changing */
-        if (st.st_size != partial_file_size)
+        if (st.pst_size != partial_file_size)
             partial_is_stale = false;
 
         sleep(1);

src/backup.c

@@ -392,7 +392,7 @@ do_backup_pg(InstanceState *instanceState, PGconn *backup_conn,
 		pgFile	   *file = (pgFile *) parray_get(backup_files_list, i);
 
 		/* if the entry was a directory, create it in the backup */
-		if (S_ISDIR(file->mode))
+		if (file->kind == PIO_KIND_DIRECTORY)
 		{
 			char		dirpath[MAXPGPATH];
 
@@ -569,7 +569,7 @@ do_backup_pg(InstanceState *instanceState, PGconn *backup_conn,
 			pgFile *file = (pgFile *) parray_get(backup_files_list, i);
 
 			/* TODO: sync directory ? */
-			if (S_ISDIR(file->mode))
+			if (file->kind == PIO_KIND_DIRECTORY)
 				continue;
 
 			if (file->write_size <= 0)
@@ -1837,7 +1837,7 @@ pg_stop_backup_write_file_helper(const char *path, const char *filename, const c
 		file = pgFileNew(full_filename, filename, true, 0,
 						 FIO_BACKUP_HOST);
 
-		if (S_ISREG(file->mode))
+		if (file->kind == PIO_KIND_REGULAR)
 		{
 			file->crc = pgFileGetCRC32C(full_filename, false);
 
@@ -1991,7 +1991,7 @@ backup_files(void *arg)
 		pgFile	*prev_file = NULL;
 
 		/* We have already copied all directories */
-		if (S_ISDIR(file->mode))
+		if (file->kind == PIO_KIND_DIRECTORY)
 			continue;
 
 		if (arguments->thread_num == 1)
@@ -2046,9 +2046,9 @@ backup_files(void *arg)
 		}
 
 		/* Encountered some strange beast */
-		if (!S_ISREG(file->mode))
-			elog(WARNING, "Unexpected type %d of file \"%s\", skipping",
-							file->mode, from_fullpath);
+		if (file->kind != PIO_KIND_REGULAR)
+			elog(WARNING, "Unexpected type %s of file \"%s\", skipping",
+				 pio_file_kind2str(file->kind, from_fullpath), from_fullpath);
 
 		/* Check that file exist in previous backup */
 		if (current.backup_mode != BACKUP_MODE_FULL)
@@ -2121,7 +2121,7 @@ parse_filelist_filenames(parray *files, const char *root)
 		pgFile	   *file = (pgFile *) parray_get(files, i);
 		int 		sscanf_result;
 
-		if (S_ISREG(file->mode) &&
+		if (file->kind == PIO_KIND_REGULAR &&
 			path_is_prefix_of_path(PG_TBLSPC_DIR, file->rel_path))
 		{
 			/*
@@ -2148,7 +2148,7 @@ parse_filelist_filenames(parray *files, const char *root)
 			}
 		}
 
-		if (S_ISREG(file->mode) && file->tblspcOid != 0 &&
+		if (file->kind == PIO_KIND_REGULAR && file->tblspcOid != 0 &&
 			file->name && file->name[0])
 		{
 			if (file->forkName == init)
@@ -2218,7 +2218,7 @@ set_cfs_datafiles(parray *files, const char *root, char *relative, size_t i)
 
 		if (strstr(prev_file->rel_path, cfs_tblspc_path) != NULL)
 		{
-			if (S_ISREG(prev_file->mode) && prev_file->is_datafile)
+			if (prev_file->kind == PIO_KIND_REGULAR && prev_file->is_datafile)
 			{
 				elog(LOG, "Setting 'is_cfs' on file %s, name %s",
 					prev_file->rel_path, prev_file->name);
@@ -2375,7 +2375,7 @@ calculate_datasize_of_filelist(parray *filelist)
 		if (file->external_dir_num != 0 || file->excluded)
 			continue;
 
-		if (S_ISDIR(file->mode))
+		if (file->kind == PIO_KIND_DIRECTORY)
 		{
 			// TODO is a dir always 4K?
 			bytes += 4096;

src/catalog.c

@@ -847,12 +847,22 @@ pgBackupGetBackupMode(pgBackup *backup, bool show_color)
 static bool
 IsDir(const char *dirpath, const char *entry, fio_location location)
 {
+	FOBJ_FUNC_ARP();
 	char		path[MAXPGPATH];
-	struct stat	st;
+	pio_stat_t	st;
+	err_i 		err;
 
 	join_path_components(path, dirpath, entry);
 
-	return fio_stat(location, path, &st, false) == 0 && S_ISDIR(st.st_mode);
+	st = $i(pioStat, pioDriveForLocation(location),
+			.path = path, .follow_symlink = false, .err = &err);
+	if ($haserr(err))
+	{
+		ft_logerr(FT_WARNING, $errmsg(err), "IsDir");
+		return false;
+	}
+
+	return st.pst_kind == PIO_KIND_DIRECTORY;
 }
 
 /*
@@ -1074,6 +1084,7 @@ get_backup_filelist(pgBackup *backup, bool strict)
 		char		path[MAXPGPATH];
 		char		linked[MAXPGPATH];
 		char		compress_alg_string[MAXPGPATH];
+		char 		kind[16];
 		int64		write_size,
 					uncompressed_size,
 					mode,		/* bit length of mode_t depends on platforms */
@@ -1115,6 +1126,11 @@ get_backup_filelist(pgBackup *backup, bool strict)
 		/*
 		 * Optional fields
 		 */
+		if (get_control_value_str(buf, "kind", kind, sizeof(kind), false))
+			file->kind = pio_str2file_kind(kind, path);
+		else /* fallback to mode for old backups */
+			file->kind = pio_statmode2file_kind(file->mode, path);
+
 		if (get_control_value_str(buf, "linked", linked, sizeof(linked), false) && linked[0])
 		{
 			file->linked = pgut_strdup(linked);
@@ -1146,7 +1162,7 @@ get_backup_filelist(pgBackup *backup, bool strict)
 		if (!file->is_datafile || file->is_cfs)
 			file->size = file->uncompressed_size;
 
-		if (file->external_dir_num == 0 && S_ISREG(file->mode))
+		if (file->external_dir_num == 0 && file->kind == PIO_KIND_REGULAR)
 		{
 			bool is_datafile = file->is_datafile;
 			set_forkname(file);
@@ -2564,14 +2580,14 @@ write_backup_filelist(pgBackup *backup, parray *files, const char *root,
 		if (file->write_size == FILE_NOT_FOUND)
 			continue;
 
-		if (S_ISDIR(file->mode))
+		if (file->kind == PIO_KIND_DIRECTORY)
 		{
 			backup_size_on_disk += 4096;
 			uncompressed_size_on_disk += 4096;
 		}
 
 		/* Count the amount of the data actually copied */
-		if (S_ISREG(file->mode) && file->write_size > 0)
+		if (file->kind == PIO_KIND_REGULAR && file->write_size > 0)
 		{
 			/*
 			 * Size of WAL files in 'pg_wal' is counted separately
@@ -2587,11 +2603,13 @@ write_backup_filelist(pgBackup *backup, parray *files, const char *root,
 		}
 
 		len = sprintf(line, "{\"path\":\"%s\", \"size\":\"" INT64_FORMAT "\", "
-					 "\"mode\":\"%u\", \"is_datafile\":\"%u\", "
+					 "\"kind\":\"%s\", \"mode\":\"%u\", \"is_datafile\":\"%u\", "
 					 "\"is_cfs\":\"%u\", \"crc\":\"%u\", "
 					 "\"compress_alg\":\"%s\", \"external_dir_num\":\"%d\", "
 					 "\"dbOid\":\"%u\"",
-					file->rel_path, file->write_size, file->mode,
+					file->rel_path, file->write_size,
+					pio_file_kind2str(file->kind, file->rel_path),
+					file->mode,
 					file->is_datafile ? 1 : 0,
 					file->is_cfs ? 1 : 0,
 					file->crc,

src/catchup.c

@@ -378,7 +378,7 @@ catchup_thread_runner(void *arg)
 		pgFile	*dest_file = NULL;
 
 		/* We have already copied all directories */
-		if (S_ISDIR(file->mode))
+		if (file->kind == PIO_KIND_DIRECTORY)
 			continue;
 
 		if (file->excluded)
@@ -400,9 +400,9 @@ catchup_thread_runner(void *arg)
 		join_path_components(to_fullpath, arguments->to_root, file->rel_path);
 
 		/* Encountered some strange beast */
-		if (!S_ISREG(file->mode))
-			elog(WARNING, "Unexpected type %d of file \"%s\", skipping",
-							file->mode, from_fullpath);
+		if (file->kind != PIO_KIND_REGULAR)
+			elog(WARNING, "Unexpected kind %s of file \"%s\", skipping",
+				 pio_file_kind2str(file->kind, from_fullpath), from_fullpath);
 
 		/* Check that file exist in dest pgdata */
 		if (arguments->backup_mode != BACKUP_MODE_FULL)
@@ -546,7 +546,7 @@ catchup_sync_destination_files(const char* pgdata_path, fio_location location, p
 		 * - but PG itself is not relying on fs, its durable_sync
 		 *   includes directory sync
 		 */
-		if (S_ISDIR(file->mode) || file->excluded)
+		if (file->kind == PIO_KIND_DIRECTORY || file->excluded)
 			continue;
 
 		Assert(file->external_dir_num == 0);
@@ -807,7 +807,7 @@ do_catchup(const char *source_pgdata, const char *dest_pgdata, int num_threads,
 		pgFile	   *file = (pgFile *) parray_get(source_filelist, i);
 		char parent_dir[MAXPGPATH];
 
-		if (!S_ISDIR(file->mode) || file->excluded)
+		if (file->kind != PIO_KIND_DIRECTORY || file->excluded)
 			continue;
 
 		/*

src/checkdb.c

@@ -147,7 +147,7 @@ check_files(void *arg)
 			elog(ERROR, "interrupted during checkdb");
 
 		/* No need to check directories */
-		if (S_ISDIR(file->mode))
+		if (file->kind == PIO_KIND_DIRECTORY)
 			continue;
 
 		if (!pg_atomic_test_set_flag(&file->lock))
@@ -161,7 +161,7 @@ check_files(void *arg)
 			elog(INFO, "Progress: (%d/%d). Process file \"%s\"",
 				 i + 1, n_files_list, from_fullpath);
 
-		if (S_ISREG(file->mode))
+		if (file->kind == PIO_KIND_REGULAR)
 		{
 			/* check only uncompressed by cfs datafiles */
 			if (file->is_datafile && !file->is_cfs)