filemap.h

/*-------------------------------------------------------------------------
 *
 * filemap.h
 *
 * Copyright (c) 2013 VMware, Inc. All Rights Reserved.
 *-------------------------------------------------------------------------
 */
#ifndef FILEMAP_H
#define FILEMAP_H

#include "storage/relfilenode.h"
#include "storage/block.h"

/*
 * For every file found in the local or remote system, we have a file entry
 * which says what we are going to do with the file. For relation files,
 * there is also a page map, marking pages in the file that were changed
 * locally.
 */
typedef enum
{
	FILE_ACTION_NONE,		/* no action (we might still copy modified blocks
							 * based on the parsed WAL) */
	FILE_ACTION_COPY,		/* copy whole file, overwriting if exists */
	FILE_ACTION_REMOVE,		/* remove local file */
	FILE_ACTION_TRUNCATE,	/* truncate local file to 'newsize' bytes */
	FILE_ACTION_COPY_TAIL,	/* copy tail from 'oldsize' to 'newsize' */
	FILE_ACTION_CREATEDIR,	/* create local dir */
} file_action_t;

struct file_entry_t
{
	char	   *path;
	bool		isdir;

	file_action_t action;

	size_t		oldsize;
	size_t		newsize;

	datapagemap_t	pagemap;

	struct file_entry_t *next;
};

typedef struct file_entry_t file_entry_t;

struct filemap_t
{
	file_entry_t *first;
	file_entry_t *last;

	/*
	 * When array is NULL, nfiles is the number of entries in the linked list.
	 * Otherwise nfiles is the number of entries in the array, but there can
	 * be more entries in the linked list.
	 */
	file_entry_t **array;
	int			nfiles;
};

typedef struct filemap_t filemap_t;

extern filemap_t * filemap;

extern filemap_t *filemap_create(void);

extern void print_filemap(void);

/* Functions for populating the filemap */
extern void process_remote_file(const char *path, size_t newsize, bool isdir);
extern void process_local_file(const char *path, size_t newsize, bool isdir);
extern void process_block_change(ForkNumber forknum, RelFileNode rnode, BlockNumber blkno);

#endif   /* FILEMAP_H */