MDEV-31039 mariadb-backup: remove global variables ds_data and ds_meta

This is a non-functional change.

simplifying the code logic:
- removing global variables ds_data and ds_meta
- passing these variables as parameters to functions instead
- adding helper classes: Datasink_free_list and Backup_datasinks
- moving some function accepting a ds_ctxt parameter
  as methods to ds_ctxt.

extra/mariabackup/backup_copy.h

@@ -14,30 +14,18 @@
 
 extern bool binlog_locked;
 
-bool
-backup_file_printf(const char *filename, const char *fmt, ...)
-		ATTRIBUTE_FORMAT(printf, 2, 0);
-
 /************************************************************************
 Return true if first and second arguments are the same path. */
 bool
 equal_paths(const char *first, const char *second);
 
-/************************************************************************
-Copy file for backup/restore.
-@return true in case of success. */
-bool
-copy_file(ds_ctxt_t *datasink,
-	  const char *src_file_path,
-	  const char *dst_file_path,
-	  uint thread_n);
-
 /** Start --backup */
-bool backup_start(CorruptedPages &corrupted_pages);
+bool backup_start(ds_ctxt *ds_data, ds_ctxt *ds_meta,
+                  CorruptedPages &corrupted_pages);
 /** Release resources after backup_start() */
 void backup_release();
 /** Finish after backup_start() and backup_release() */
-bool backup_finish();
+bool backup_finish(ds_ctxt *ds_data);
 bool
 apply_log_finish();
 bool
@@ -51,6 +39,5 @@ directory_exists(const char *dir, bool create);
 
 lsn_t
 get_current_lsn(MYSQL *connection);
-bool backup_file_print_buf(const char *filename, const char *buf, int buf_len);
 
 #endif

extra/mariabackup/backup_mysql.cc

@@ -1383,7 +1383,7 @@ variable.
 @returns true on success
 */
 bool
-write_slave_info(MYSQL *connection)
+write_slave_info(ds_ctxt *datasink, MYSQL *connection)
 {
   String sql, comment;
   bool show_all_slaves_status= false;
@@ -1413,7 +1413,8 @@ write_slave_info(MYSQL *connection)
   }
 
   mysql_slave_position= strdup(comment.c_ptr());
-  return backup_file_print_buf(XTRABACKUP_SLAVE_INFO, sql.ptr(), sql.length());
+  return datasink->backup_file_print_buf(XTRABACKUP_SLAVE_INFO,
+                               sql.ptr(), sql.length());
 }
 
 
@@ -1421,7 +1422,7 @@ write_slave_info(MYSQL *connection)
 Retrieves MySQL Galera and
 saves it in a file. It also prints it to stdout. */
 bool
-write_galera_info(MYSQL *connection)
+write_galera_info(ds_ctxt *datasink, MYSQL *connection)
 {
 	char *state_uuid = NULL, *state_uuid55 = NULL;
 	char *last_committed = NULL, *last_committed55 = NULL;
@@ -1453,12 +1454,12 @@ write_galera_info(MYSQL *connection)
 		goto cleanup;
 	}
 
-	result = backup_file_printf(XTRABACKUP_GALERA_INFO,
+	result = datasink->backup_file_printf(XTRABACKUP_GALERA_INFO,
 		"%s:%s\n", state_uuid ? state_uuid : state_uuid55,
 			last_committed ? last_committed : last_committed55);
 	if (result)
 	{
-		write_current_binlog_file(connection);
+		write_current_binlog_file(datasink, connection);
 	}
 
 cleanup:
@@ -1472,7 +1473,7 @@ write_galera_info(MYSQL *connection)
 Flush and copy the current binary log file into the backup,
 if GTID is enabled */
 bool
-write_current_binlog_file(MYSQL *connection)
+write_current_binlog_file(ds_ctxt *datasink, MYSQL *connection)
 {
 	char *executed_gtid_set = NULL;
 	char *gtid_binlog_state = NULL;
@@ -1542,7 +1543,7 @@ write_current_binlog_file(MYSQL *connection)
 
 		snprintf(filepath, sizeof(filepath), "%s%c%s",
 			 log_bin_dir, FN_LIBCHAR, log_bin_file);
-		result = copy_file(ds_data, filepath, log_bin_file, 0);
+		result = datasink->copy_file(filepath, log_bin_file, 0);
 	}
 
 cleanup:
@@ -1558,7 +1559,7 @@ write_current_binlog_file(MYSQL *connection)
 Retrieves MySQL binlog position and
 saves it in a file. It also prints it to stdout. */
 bool
-write_binlog_info(MYSQL *connection)
+write_binlog_info(ds_ctxt *datasink, MYSQL *connection)
 {
 	char *filename = NULL;
 	char *position = NULL;
@@ -1603,14 +1604,14 @@ write_binlog_info(MYSQL *connection)
 			"filename '%s', position '%s', "
 			"GTID of the last change '%s'",
 			filename, position, gtid) != -1);
-		result = backup_file_printf(XTRABACKUP_BINLOG_INFO,
+		result = datasink->backup_file_printf(XTRABACKUP_BINLOG_INFO,
 					    "%s\t%s\t%s\n", filename, position,
 					    gtid);
 	} else {
 		ut_a(asprintf(&mysql_binlog_position,
 			"filename '%s', position '%s'",
 			filename, position) != -1);
-		result = backup_file_printf(XTRABACKUP_BINLOG_INFO,
+		result = datasink->backup_file_printf(XTRABACKUP_BINLOG_INFO,
 					    "%s\t%s\n", filename, position);
 	}
 
@@ -1650,8 +1651,9 @@ PERCONA_SCHEMA.xtrabackup_history and writes a new history record to the
 table containing all the history info particular to the just completed
 backup. */
 bool
-write_xtrabackup_info(MYSQL *connection, const char * filename, bool history,
-                       bool stream)
+write_xtrabackup_info(ds_ctxt *datasink,
+                      MYSQL *connection, const char * filename, bool history,
+                      bool stream)
 {
 
 	bool result = true;
@@ -1727,7 +1729,7 @@ write_xtrabackup_info(MYSQL *connection, const char * filename, bool history,
 	}
 
 	if (stream) {
-		backup_file_printf(filename, "%s", buf);
+		datasink->backup_file_printf(filename, "%s", buf);
 	} else {
 		fp = fopen(filename, "w");
 		if (!fp) {
@@ -1848,9 +1850,9 @@ static std::string make_local_paths(const char *data_file_path)
 	return buf.str();
 }
 
-bool write_backup_config_file()
+bool write_backup_config_file(ds_ctxt *datasink)
 {
-	int rc= backup_file_printf("backup-my.cnf",
+	int rc= datasink->backup_file_printf("backup-my.cnf",
 		"# This MySQL options file was generated by innobackupex.\n\n"
 		"# The MySQL server\n"
 		"[mysqld]\n"

extra/mariabackup/backup_mysql.h

@@ -62,17 +62,18 @@ void
 unlock_all(MYSQL *connection);
 
 bool
-write_current_binlog_file(MYSQL *connection);
+write_current_binlog_file(ds_ctxt *datasink, MYSQL *connection);
 
 bool
-write_binlog_info(MYSQL *connection);
+write_binlog_info(ds_ctxt *datasink, MYSQL *connection);
 
 bool
-write_xtrabackup_info(MYSQL *connection, const char * filename, bool history,
-                       bool stream);
+write_xtrabackup_info(ds_ctxt *datasink,
+                      MYSQL *connection, const char * filename, bool history,
+                      bool stream);
 
 bool
-write_backup_config_file();
+write_backup_config_file(ds_ctxt *datasink);
 
 bool
 lock_binlog_maybe(MYSQL *connection);
@@ -84,10 +85,10 @@ bool
 wait_for_safe_slave(MYSQL *connection);
 
 bool
-write_galera_info(MYSQL *connection);
+write_galera_info(ds_ctxt *datasink, MYSQL *connection);
 
 bool
-write_slave_info(MYSQL *connection);
+write_slave_info(ds_ctxt *datasink, MYSQL *connection);
 
 
 #endif

extra/mariabackup/datasink.h

@@ -37,6 +37,35 @@ typedef struct ds_ctxt {
 	char 		*root;
 	void		*ptr;
 	struct ds_ctxt	*pipe_ctxt;
+	/*
+          Copy file for backup/restore.
+          @return true in case of success.
+        */
+        bool copy_file(const char *src_file_path,
+                       const char *dst_file_path,
+                       uint thread_n);
+
+        bool move_file(const char *src_file_path,
+                       const char *dst_file_path,
+                       const char *dst_dir,
+                       uint thread_n);
+
+        bool make_hardlink(const char *from_path, const char *to_path);
+
+        void copy_or_move_dir(const char *from, const char *to,
+                              bool do_copy, bool allow_hardlinks);
+
+        bool backup_file_vprintf(const char *filename,
+                                 const char *fmt, va_list ap);
+
+        bool backup_file_print_buf(const char *filename,
+                                   const char *buf,
+                                   int buf_len);
+
+        bool backup_file_printf(const char *filename,
+                                const char *fmt, ...)
+                                ATTRIBUTE_FORMAT(printf, 2, 0);
+
 } ds_ctxt_t;
 
 typedef struct {

extra/mariabackup/write_filt.cc

@@ -31,7 +31,8 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1335  USA
 
 /************************************************************************
 Write-through page write filter. */
-static my_bool wf_wt_init(xb_write_filt_ctxt_t *ctxt, char *dst_name,
+static my_bool wf_wt_init(ds_ctxt *ds_meta,
+                          xb_write_filt_ctxt_t *ctxt, char *dst_name,
 			  xb_fil_cur_t *cursor, CorruptedPages *corrupted_pages);
 static my_bool wf_wt_process(xb_write_filt_ctxt_t *ctxt, ds_file_t *dstfile);
 
@@ -44,7 +45,8 @@ xb_write_filt_t wf_write_through = {
 
 /************************************************************************
 Incremental page write filter. */
-static my_bool wf_incremental_init(xb_write_filt_ctxt_t *ctxt, char *dst_name,
+static my_bool wf_incremental_init(ds_ctxt *ds_meta,
+                                   xb_write_filt_ctxt_t *ctxt, char *dst_name,
 				   xb_fil_cur_t *cursor, CorruptedPages *corrupted_pages);
 static my_bool wf_incremental_process(xb_write_filt_ctxt_t *ctxt,
 				      ds_file_t *dstfile);
@@ -64,7 +66,8 @@ Initialize incremental page write filter.
 
 @return TRUE on success, FALSE on error. */
 static my_bool
-wf_incremental_init(xb_write_filt_ctxt_t *ctxt, char *dst_name,
+wf_incremental_init(ds_ctxt *ds_meta,
+                    xb_write_filt_ctxt_t *ctxt, char *dst_name,
 		    xb_fil_cur_t *cursor, CorruptedPages *corrupted_pages)
 {
 	char				meta_name[FN_REFLEN];
@@ -88,7 +91,7 @@ wf_incremental_init(xb_write_filt_ctxt_t *ctxt, char *dst_name,
 		 XB_DELTA_INFO_SUFFIX);
 	const xb_delta_info_t	info(cursor->page_size, cursor->zip_size,
 				     cursor->space_id);
-	if (!xb_write_delta_metadata(meta_name, &info)) {
+	if (!xb_write_delta_metadata(ds_meta, meta_name, &info)) {
 		msg(cursor->thread_n,"Error: "
 		    "failed to write meta info for %s",
 		    cursor->rel_path);
@@ -195,7 +198,8 @@ Initialize the write-through page write filter.
 
 @return TRUE on success, FALSE on error. */
 static my_bool
-wf_wt_init(xb_write_filt_ctxt_t *ctxt, char *dst_name __attribute__((unused)),
+wf_wt_init(ds_ctxt *ds_meta __attribute__((unused)),
+           xb_write_filt_ctxt_t *ctxt, char *dst_name __attribute__((unused)),
 	   xb_fil_cur_t *cursor, CorruptedPages *)
 {
 	ctxt->cursor = cursor;

extra/mariabackup/write_filt.h

@@ -45,7 +45,8 @@ typedef struct {
 
 
 typedef struct {
-	my_bool	(*init)(xb_write_filt_ctxt_t *ctxt, char *dst_name,
+	my_bool	(*init)(ds_ctxt *ds_meta,
+	                xb_write_filt_ctxt_t *ctxt, char *dst_name,
 			xb_fil_cur_t *cursor, CorruptedPages *corrupted_pages);
 	my_bool	(*process)(xb_write_filt_ctxt_t *ctxt, ds_file_t *dstfile);
 	my_bool	(*finalize)(xb_write_filt_ctxt_t *, ds_file_t *dstfile);

extra/mariabackup/xtrabackup.h

@@ -46,11 +46,13 @@ class CorruptedPages
   bool contains(ulint space_id, ulint page_no) const;
   void drop_space(ulint space_id);
   void rename_space(ulint space_id, const std::string &new_name);
-  bool print_to_file(const char *file_name) const;
+  bool print_to_file(ds_ctxt *ds_data, const char *file_name) const;
   void read_from_file(const char *file_name);
   bool empty() const;
   void zero_out_free_pages();
 
+  void backup_fix_ddl(ds_ctxt *ds_data, ds_ctxt *ds_meta);
+
 private:
   void add_page_no_lock(const char *space_name, ulint space_id, ulint page_no,
                         bool convert_space_name);
@@ -63,6 +65,7 @@ class CorruptedPages
   container_t m_spaces;
 };
 
+
 /* value of the --incremental option */
 extern lsn_t incremental_lsn;
 
@@ -76,8 +79,6 @@ extern char		*xb_rocksdb_datadir;
 extern my_bool	xb_backup_rocksdb;
 
 extern uint		opt_protocol;
-extern ds_ctxt_t	*ds_meta;
-extern ds_ctxt_t	*ds_data;
 
 /* The last checkpoint LSN at the backup startup time */
 extern lsn_t checkpoint_lsn_start;
@@ -177,7 +178,8 @@ extern ulong opt_binlog_info;
 extern ulong xtrabackup_innodb_force_recovery;
 
 void xtrabackup_io_throttling(void);
-my_bool xb_write_delta_metadata(const char *filename,
+my_bool xb_write_delta_metadata(ds_ctxt *ds_meta,
+                                const char *filename,
 				const xb_delta_info_t *info);
 
 /************************************************************************