postgresql/src/bin/pg_dump/pg_backup_null.c

/*-------------------------------------------------------------------------
 *
 * pg_backup_null.c
 *
 *	Implementation of an archive that is never saved; it is used by
 *	pg_dump to output a plain text SQL script instead of save
 *	a real archive.
 *
 *	See the headers to pg_restore for more details.
 *
 * Copyright (c) 2000, Philip Warner
 *		Rights are granted to use this software in any way so long
 *		as this notice is not removed.
 *
 *	The author is not responsible for loss or damages that may
 *	result from it's use.
 *
 *
 * IDENTIFICATION
 *		$Header: /cvsroot/pgsql/src/bin/pg_dump/pg_backup_null.c,v 1.9 2002/05/10 22:36:26 tgl Exp $
 *
 * Modifications - 09-Jul-2000 - pjw@rhyme.com.au
 *
 *	Initial version.
 *
 * Modifications - 04-Jan-2001 - pjw@rhyme.com.au
 *
 *	  - Check results of IO routines more carefully.
 *
 *
 *-------------------------------------------------------------------------
 */

#include "pg_backup.h"
#include "pg_backup_archiver.h"

#include <stdlib.h>
#include <string.h>
#include <unistd.h>				/* for dup */

static int	_WriteData(ArchiveHandle *AH, const void *data, int dLen);
static void _EndData(ArchiveHandle *AH, TocEntry *te);
static int	_WriteByte(ArchiveHandle *AH, const int i);
static int	_WriteBuf(ArchiveHandle *AH, const void *buf, int len);
static void _CloseArchive(ArchiveHandle *AH);
static void _PrintTocData(ArchiveHandle *AH, TocEntry *te, RestoreOptions *ropt);

/*
 *	Initializer
 */
void
InitArchiveFmt_Null(ArchiveHandle *AH)
{
	/* Assuming static functions, this can be copied for each format. */
	AH->WriteDataPtr = _WriteData;
	AH->EndDataPtr = _EndData;
	AH->WriteBytePtr = _WriteByte;
	AH->WriteBufPtr = _WriteBuf;
	AH->ClosePtr = _CloseArchive;
	AH->PrintTocDataPtr = _PrintTocData;

	/*
	 * Now prevent reading...
	 */
	if (AH->mode == archModeRead)
		die_horribly(AH, NULL, "this format cannot be read\n");
}

/*
 * - Start a new TOC entry
 */

/*------
 * Called by dumper via archiver from within a data dump routine
 * As at V1.3, this is only called for COPY FROM dfata, and BLOB data
 *------
 */
static int
_WriteData(ArchiveHandle *AH, const void *data, int dLen)
{
	/* Just send it to output */
	ahwrite(data, 1, dLen, AH);
	return dLen;
}

static void
_EndData(ArchiveHandle *AH, TocEntry *te)
{
	ahprintf(AH, "\n\n");
}

/*------
 * Called as part of a RestoreArchive call; for the NULL archive, this
 * just sends the data for a given TOC entry to the output.
 *------
 */
static void
_PrintTocData(ArchiveHandle *AH, TocEntry *te, RestoreOptions *ropt)
{
	if (te->dataDumper)
	{
		AH->currToc = te;
		(*te->dataDumper) ((Archive *) AH, te->oid, te->dataDumperArg);
		AH->currToc = NULL;
	}
}

static int
_WriteByte(ArchiveHandle *AH, const int i)
{
	/* Don't do anything */
	return 0;
}

static int
_WriteBuf(ArchiveHandle *AH, const void *buf, int len)
{
	/* Don't do anything */
	return len;
}

static void
_CloseArchive(ArchiveHandle *AH)
{
	/* Nothing to do */
}