/*
 *	PROGRAM:	JRD Backup and Restore Program
 *	MODULE:		multivol.cpp
 *	DESCRIPTION:
 *
 * The contents of this file are subject to the Interbase Public
 * License Version 1.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy
 * of the License at http://www.Inprise.com/IPL.html
 *
 * Software distributed under the License is distributed on an
 * "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express
 * or implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code was created by Inprise Corporation
 * and its predecessors. Portions created by Inprise Corporation are
 * Copyright (C) Inprise Corporation.
 *
 * All Rights Reserved.
 * Contributor(s): ______________________________________.
 *
 * 2002.10.29 Sean Leyne - Removed obsolete "Netware" port
 *
 */

#include "firebird.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#if TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
#else
# if HAVE_SYS_TIME_H
#  include <sys/time.h>
# else
#  include <time.h>
# endif
#endif
#include "../burp/burp.h"
#include "../burp/burp_proto.h"
#include "../burp/mvol_proto.h"
#include "../jrd/gds_proto.h"
#include "../jrd/gdsassert.h"
#include <fcntl.h>
#include <sys/types.h>

#ifdef HAVE_IO_H
#include <io.h>  // isatty
#endif

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include "../common/classes/SafeArg.h"

using MsgFormat::SafeArg;


const int open_mask	= 0666;

#ifdef WIN_NT
const char* TERM_INPUT	= "CONIN$";
const char* TERM_OUTPUT	= "CONOUT$";
#else
const char* TERM_INPUT	= "/dev/tty";
const char* TERM_OUTPUT	= "/dev/tty";
#endif

const int MAX_HEADER_SIZE	= 512;

static inline int get(BurpGlobals* tdgbl)
{
	return (--tdgbl->mvol_io_cnt >= 0 ? *tdgbl->mvol_io_ptr++ : 255);
}

static inline void put(BurpGlobals* tdgbl, UCHAR c)
{
	--tdgbl->mvol_io_cnt;
	*tdgbl->mvol_io_ptr++ = c;
}

#ifdef DEBUG
static UCHAR debug_on = 0;		// able to turn this on in debug mode
#endif

const int burp_msg_fac = 12;


static void  bad_attribute(int, USHORT);
static void  file_not_empty();
static SLONG get_numeric();
static int   get_text(UCHAR*, SSHORT);
static void  prompt_for_name(SCHAR*, int);
static void  put_asciz(SCHAR, const SCHAR*);
static void  put_numeric(SCHAR, int);
static bool  read_header(DESC, ULONG*, USHORT*, bool);
static bool  write_header(DESC, ULONG, bool);
static DESC	 next_volume(DESC, ULONG, bool);


//____________________________________________________________
//
//
FB_UINT64 MVOL_fini_read()
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	if (strcmp(tdgbl->mvol_old_file, "stdin") != 0)
	{
		close_platf(tdgbl->file_desc);

		for (burp_fil* file = tdgbl->gbl_sw_backup_files; file; file = file->fil_next)
		{
			if (file->fil_fd == tdgbl->file_desc) {
				file->fil_fd = INVALID_HANDLE_VALUE;
			}
		}
	}

	tdgbl->file_desc = INVALID_HANDLE_VALUE;
	BURP_free(tdgbl->mvol_io_buffer);
	tdgbl->mvol_io_buffer = NULL;
	tdgbl->io_cnt = 0;
	tdgbl->io_ptr = NULL;
	return tdgbl->mvol_cumul_count;
}


//____________________________________________________________
//
//
FB_UINT64 MVOL_fini_write(int* io_cnt, UCHAR** io_ptr)
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	MVOL_write(rec_end, io_cnt, io_ptr);
	flush_platf(tdgbl->file_desc);
	if (strcmp(tdgbl->mvol_old_file, "stdout") != 0)
	{
		close_platf(tdgbl->file_desc);
		for (burp_fil* file = tdgbl->gbl_sw_backup_files; file; file = file->fil_next)
		{
			if (file->fil_fd == tdgbl->file_desc)
				file->fil_fd = INVALID_HANDLE_VALUE;
		}
	}
	tdgbl->file_desc = INVALID_HANDLE_VALUE;
	BURP_free(tdgbl->mvol_io_header);
	tdgbl->mvol_io_header = NULL;
	tdgbl->mvol_io_buffer = NULL;
	tdgbl->io_cnt = 0;
	tdgbl->io_ptr = NULL;
	return tdgbl->mvol_cumul_count;
}


//____________________________________________________________
//
//
void MVOL_init(ULONG io_buf_size)
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	tdgbl->mvol_io_buffer_size = io_buf_size;
}


//____________________________________________________________
//
// Read init record from backup file
//
void MVOL_init_read(const char* database_name, // unused?
					const char* file_name,
					USHORT*	format,
					int*	cnt,
					UCHAR**	ptr)
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	tdgbl->mvol_volume_count = 1;
	tdgbl->mvol_empty_file = true;

	if (file_name != NULL)
	{
		strncpy(tdgbl->mvol_old_file, file_name, MAX_FILE_NAME_SIZE);
		tdgbl->mvol_old_file[MAX_FILE_NAME_SIZE - 1] = 0;
	}
	else
	{
		tdgbl->mvol_old_file[0] = 0;
	}

	ULONG temp_buffer_size = tdgbl->mvol_io_buffer_size;
	tdgbl->mvol_actual_buffer_size = temp_buffer_size;
	tdgbl->mvol_io_buffer = BURP_alloc(temp_buffer_size);
	tdgbl->gbl_backup_start_time[0] = 0;

	read_header(tdgbl->file_desc, &temp_buffer_size, format, true);

	if (temp_buffer_size > tdgbl->mvol_actual_buffer_size)
	{
		UCHAR* new_buffer = BURP_alloc(temp_buffer_size);
		memcpy(new_buffer, tdgbl->mvol_io_buffer, tdgbl->mvol_io_buffer_size);
		BURP_free(tdgbl->mvol_io_buffer);
		tdgbl->mvol_io_ptr = new_buffer + (tdgbl->mvol_io_ptr - tdgbl->mvol_io_buffer);
		tdgbl->mvol_io_buffer = new_buffer;
	}

	tdgbl->mvol_actual_buffer_size = tdgbl->mvol_io_buffer_size = temp_buffer_size;
	*cnt = tdgbl->mvol_io_cnt;
	*ptr = tdgbl->mvol_io_ptr;
}


//____________________________________________________________
//
// Write init record to the backup file
//
void MVOL_init_write(const char*		database_name, // unused?
					 const char*		file_name,
					 int*		cnt,
					 UCHAR**	ptr)
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	tdgbl->mvol_volume_count = 1;
	tdgbl->mvol_empty_file = true;

	if (file_name != NULL)
	{
		strncpy(tdgbl->mvol_old_file, file_name, MAX_FILE_NAME_SIZE);
		tdgbl->mvol_old_file[MAX_FILE_NAME_SIZE - 1] = 0;
	}
	else
	{
		tdgbl->mvol_old_file[0] = 0;
	}

	tdgbl->mvol_actual_buffer_size = tdgbl->mvol_io_buffer_size;
	const ULONG temp_buffer_size = tdgbl->mvol_io_buffer_size * tdgbl->gbl_sw_blk_factor;
	tdgbl->mvol_io_ptr = tdgbl->mvol_io_buffer = BURP_alloc(temp_buffer_size + MAX_HEADER_SIZE);
	tdgbl->mvol_io_cnt = tdgbl->mvol_actual_buffer_size;

	while (!write_header(tdgbl->file_desc, temp_buffer_size, false))
	{
		if (tdgbl->action->act_action == ACT_backup_split)
		{
			BURP_error(269, true, tdgbl->action->act_file->fil_name.c_str());
			// msg 269 can't write a header record to file %s
		}
		tdgbl->file_desc = next_volume(tdgbl->file_desc, MODE_WRITE, false);
	}

	tdgbl->mvol_actual_buffer_size = temp_buffer_size;

	*cnt = tdgbl->mvol_io_cnt;
	*ptr = tdgbl->mvol_io_ptr;
}


#ifndef WIN_NT
//____________________________________________________________
//
// Read a buffer's worth of data. (non-WIN_NT)
//
int MVOL_read(int* cnt, UCHAR** ptr)
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	for (;;)
	{
		tdgbl->mvol_io_cnt = read(tdgbl->file_desc, tdgbl->mvol_io_buffer, tdgbl->mvol_io_buffer_size);
		tdgbl->mvol_io_ptr = tdgbl->mvol_io_buffer;

		if (tdgbl->mvol_io_cnt > 0) {
			break;
		}

		if (!tdgbl->mvol_io_cnt || errno == EIO)
		{
			tdgbl->file_desc = next_volume(tdgbl->file_desc, MODE_READ, false);
			if (tdgbl->mvol_io_cnt > 0)
			{
				break;
			}
		}
		else if (!SYSCALL_INTERRUPTED(errno))
		{
			if (cnt)
			{
				BURP_error_redirect(0, 220);
				// msg 220 Unexpected I/O error while reading from backup file
			}
			else
			{
				BURP_error_redirect(0, 50);
				// msg 50 unexpected end of file on backup file
			}
		}
	}

	tdgbl->mvol_cumul_count += tdgbl->mvol_io_cnt;
	file_not_empty();

	*ptr = tdgbl->mvol_io_ptr + 1;
	*cnt = tdgbl->mvol_io_cnt - 1;

	return *tdgbl->mvol_io_ptr;
}


#else
//____________________________________________________________
//
// Read a buffer's worth of data. (WIN_NT)
//
int MVOL_read(int* cnt, UCHAR** ptr)
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	fb_assert(tdgbl->io_cnt <= 0);

	for (;;)
	{
		DWORD bytesRead = 0;
		const BOOL ret = ReadFile(tdgbl->file_desc, tdgbl->mvol_io_buffer,
								  tdgbl->mvol_io_buffer_size, &bytesRead, NULL);
		tdgbl->mvol_io_cnt = bytesRead;
		tdgbl->mvol_io_ptr = tdgbl->mvol_io_buffer;
		if (tdgbl->mvol_io_cnt > 0)
			break;

		if (!tdgbl->mvol_io_cnt && ret)
		{
			tdgbl->file_desc = next_volume(tdgbl->file_desc, MODE_READ, false);
			if (tdgbl->mvol_io_cnt > 0)
				break;
		}
		else if (GetLastError() != ERROR_HANDLE_EOF)
		{
			if (cnt)
				BURP_error_redirect(NULL, 220);
				// msg 220 Unexpected I/O error while reading from backup file
			else
				BURP_error_redirect(NULL, 50);
				// msg 50 unexpected end of file on backup file
		}
	}

	tdgbl->mvol_cumul_count += tdgbl->mvol_io_cnt;
	file_not_empty();

	*ptr = tdgbl->mvol_io_ptr + 1;
	*cnt = tdgbl->mvol_io_cnt - 1;

	return *tdgbl->mvol_io_ptr;
}
#endif // !WIN_NT


//____________________________________________________________
//
// Read a chunk of data from the IO buffer.
// Return a pointer to the first position NOT read into.
//
UCHAR* MVOL_read_block(BurpGlobals* tdgbl, UCHAR* ptr, ULONG count)
{
// To handle tape drives & Multi-volume boundaries, use the normal
// read function, instead of doing a more optimal bulk read.


	while (count)
	{
		// If buffer empty, reload it
		if (tdgbl->io_cnt <= 0)
		{
			*ptr++ = MVOL_read(&tdgbl->io_cnt, &tdgbl->io_ptr);

			// One byte was "read" by MVOL_read
			count--;
		}

		const ULONG n = MIN(count, (ULONG) tdgbl->io_cnt);

		// Copy data from the IO buffer

		memcpy(ptr, tdgbl->io_ptr, n);
		ptr += n;

		// Skip ahead in current buffer

		count -= n;
		tdgbl->io_cnt -= n;
		tdgbl->io_ptr += n;

	}
	return ptr;
}


//____________________________________________________________
//
// Skip head in the IO buffer.  Often used when only
// doing partial restores.
//
void MVOL_skip_block( BurpGlobals* tdgbl, ULONG count)
{
// To handle tape drives & Multi-volume boundaries, use the normal
// read function, instead of doing a more optimal seek.


	while (count)
	{
		// If buffer empty, reload it
		if (tdgbl->io_cnt <= 0)
		{
			MVOL_read(&tdgbl->io_cnt, &tdgbl->io_ptr);

			// One byte was "read" by MVOL_read
			count--;
		}

		const ULONG n = MIN(count, (ULONG) tdgbl->io_cnt);

		// Skip ahead in current buffer

		count -= n;
		tdgbl->io_cnt -= n;
		tdgbl->io_ptr += n;
	}
}


#ifdef WIN_NT
//____________________________________________________________
//
// detect if it's a tape, rewind if so
// and set the buffer size
//
DESC MVOL_open(const char* name, ULONG mode, ULONG create)
{
	HANDLE handle;
	TAPE_GET_MEDIA_PARAMETERS param;
	DWORD size = sizeof(param);

	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	if (strnicmp(name, "\\\\.\\tape", 8))
	{
		handle = CreateFile(name, mode,
							mode == MODE_WRITE ? 0 : FILE_SHARE_READ,
							NULL, create, FILE_ATTRIBUTE_NORMAL, NULL);
	}
	else
	{
		// it's a tape device
		// Note: we *want* to open the tape in Read-only mode or in
		// write-only mode, but it turns out that on NT SetTapePosition
		// will fail (thereby not rewinding the tape) if the tape is
		// opened write-only, so we will make sure that we always have
		// read access. So much for standards!
		// Ain't Windows wonderful???
		//
		// Note: we *want* to open the tape in FILE_EXCLUSIVE_WRITE, but
		// during testing discovered that several NT tape drives do not
		// work unless we specify FILE_SHARE_WRITE as the open mode.
		// So it goes...
		//
		handle = CreateFile(name, mode | MODE_READ,
							mode == MODE_WRITE ? FILE_SHARE_WRITE : FILE_SHARE_READ,
							0, OPEN_EXISTING, 0, NULL);
		if (handle != INVALID_HANDLE_VALUE)
		{
			// emulate UNIX rewinding the tape on open:
			// This MUST be done since Windows does NOT have anything
			// like mt to allow the user to do tape management. The
			// implication here is that we will be able to write ONLY
			// one (1) database per tape. This is bad if the user wishes to
			// backup several small databases.
			// Note: We are intentionally NOT trapping for errors during
			// rewind, since if we can not rewind, we are either a non-rewind
			// device (then it is user controlled) or we have a problem with
			// the physical media.  In the latter case I would rather wait for
			// the write to fail so that we can loop and prompt the user for
			// a different file/device.
			//
			SetTapePosition(handle, TAPE_REWIND, 0, 0, 0, FALSE);
			if (GetTapeParameters(handle, GET_TAPE_MEDIA_INFORMATION, &size, &param) == NO_ERROR)
			{
				tdgbl->io_buffer_size = param.BlockSize;
			}
		}
	}
	return handle;
}
#endif // WIN_NT


//____________________________________________________________
//
// Write a buffer's worth of data.
//
UCHAR MVOL_write(const UCHAR c, int* io_cnt, UCHAR** io_ptr)
{
	const UCHAR* ptr;
	ULONG cnt = 0;

	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	const ULONG size_to_write = BURP_UP_TO_BLOCK(*io_ptr - tdgbl->mvol_io_buffer);
	ULONG left = size_to_write;

	for (ptr = tdgbl->mvol_io_buffer; left > 0; ptr += cnt, left -= cnt)
	{
		if (tdgbl->action->act_action == ACT_backup_split)
		{
			// Write to the current file till fil_lingth > 0, otherwise
			// switch to the next one
			if (tdgbl->action->act_file->fil_length == 0)
			{
				if (tdgbl->action->act_file->fil_next)
				{
					close_platf(tdgbl->file_desc);
					for (burp_fil* file = tdgbl->gbl_sw_backup_files; file; file = file->fil_next)
					{
						if (file->fil_fd == tdgbl->file_desc)
							file->fil_fd = INVALID_HANDLE_VALUE;
					}
					tdgbl->action->act_file->fil_fd = INVALID_HANDLE_VALUE;
					tdgbl->action->act_file = tdgbl->action->act_file->fil_next;
					tdgbl->file_desc = tdgbl->action->act_file->fil_fd;
				}
				else
				{
					// This is a last file. Keep writing in a hope that there is
					// enough free disk space ...
					tdgbl->action->act_file->fil_length = MAX_LENGTH;
				}
			}
		}

		const size_t nBytesToWrite =
			(tdgbl->action->act_action == ACT_backup_split &&
				tdgbl->action->act_file->fil_length < left) ?
			 		tdgbl->action->act_file->fil_length : left;

#ifndef WIN_NT
		cnt = write(tdgbl->file_desc, ptr, nBytesToWrite);
#else

		DWORD ret = 0;
		if (!WriteFile(tdgbl->file_desc, ptr, (DWORD) nBytesToWrite, &cnt, NULL))
		{
			ret = GetLastError();
		}
#endif // !WIN_NT
		tdgbl->mvol_io_buffer = tdgbl->mvol_io_data;
		if (cnt > 0)
		{
			tdgbl->mvol_cumul_count += cnt;
			file_not_empty();
			if (tdgbl->action->act_action == ACT_backup_split)
			{
				if (tdgbl->action->act_file->fil_length < left)
					tdgbl->action->act_file->fil_length = 0;
				else
					tdgbl->action->act_file->fil_length -= left;
			}
		}
		else
		{
			if (!cnt ||
#ifndef WIN_NT
				errno == ENOSPC || errno == EIO || errno == ENXIO ||
				errno == EFBIG)
#else
				ret == ERROR_DISK_FULL || ret == ERROR_HANDLE_DISK_FULL)
#endif // !WIN_NT
			{
				if (tdgbl->action->act_action == ACT_backup_split)
				{
					// Close the current file and switch to the next one.
					// If there is no more specified files left then
					// issue an error and give up
					if (tdgbl->action->act_file->fil_next)
					{
						close_platf(tdgbl->file_desc);
						for (burp_fil* file = tdgbl->gbl_sw_backup_files; file; file = file->fil_next)
						{
							if (file->fil_fd == tdgbl->file_desc)
								file->fil_fd = INVALID_HANDLE_VALUE;
						}

						tdgbl->action->act_file->fil_fd = INVALID_HANDLE_VALUE;
						BURP_print(272, SafeArg() <<
									tdgbl->action->act_file->fil_name.c_str() <<
									tdgbl->action->act_file->fil_length <<
									tdgbl->action->act_file->fil_next->fil_name.c_str());
						// msg 272 Warning -- free disk space exhausted for file %s,
						// the rest of the bytes (%d) will be written to file %s
						tdgbl->action->act_file->fil_next->fil_length +=
							tdgbl->action->act_file->fil_length;
						tdgbl->action->act_file = tdgbl->action->act_file->fil_next;
						tdgbl->file_desc = tdgbl->action->act_file->fil_fd;
					}
					else
					{
						BURP_error(270, true);
						// msg 270 free disk space exhausted
					}
					cnt = 0;
					continue;
				}

				if (tdgbl->uSvc->isService())
				{
					BURP_error(270, true);
					// msg 270 free disk space exhausted
				}

				// Note: there is an assumption here, that if header data is being
				// written, it is really being rewritten, so at least all the
				// header data will be written

				if (left != size_to_write)
				{
					// Wrote some, move remainder up in buffer.

					// NOTE: We should NOT use memcpy here.  We're moving overlapped
					// data and memcpy does not guanantee the order the data
					// is moved in
					memcpy(tdgbl->mvol_io_data, ptr, left);
				}
				left += tdgbl->mvol_io_data - tdgbl->mvol_io_header;
				bool full_buffer;
				if (left >=  tdgbl->mvol_io_buffer_size)
					full_buffer = true;
				else
					full_buffer = false;
				tdgbl->file_desc = next_volume(tdgbl->file_desc, MODE_WRITE, full_buffer);
				if (full_buffer)
				{
					left -= tdgbl->mvol_io_buffer_size;
					memcpy(tdgbl->mvol_io_data,
						   tdgbl->mvol_io_header + tdgbl->mvol_io_buffer_size,
						   left);
					tdgbl->mvol_cumul_count += tdgbl->mvol_io_buffer_size;
					tdgbl->mvol_io_buffer = tdgbl->mvol_io_data;
				}
				else
					tdgbl->mvol_io_buffer = tdgbl->mvol_io_header;
				break;
			}
			else if (!SYSCALL_INTERRUPTED(errno))
			{
				BURP_error_redirect(0, 221);
				// msg 221 Unexpected I/O error while writing to backup file
			}
		}
		if (left < cnt) {	// this is impossible, but...
			cnt = left;
		}

	} // for

#ifdef DEBUG
	{
		int dbg_cnt;
		if (debug_on)
		{
			for (dbg_cnt = 0; dbg_cnt < cnt; dbg_cnt++)
				printf("%d,\n", *(ptr + dbg_cnt));
		}
	}
#endif

// After the first block of first volume is written (using a default block size)
// change the block size to one that reflects the user's blocking factor.  By
// making the first block a standard size we will avoid restore problems.

	tdgbl->mvol_io_buffer_size = tdgbl->mvol_actual_buffer_size;

	UCHAR* newptr = tdgbl->mvol_io_buffer + left;
	*newptr++ = c;
	*io_ptr = newptr;
	*io_cnt = tdgbl->mvol_io_buffer_size - 1 - left;

	return c;
}


//____________________________________________________________
//
// Write a chunk of data to the IO buffer.
// Return a pointer to the first position NOT written from.
//
const UCHAR* MVOL_write_block(BurpGlobals* tdgbl, const UCHAR* ptr, ULONG count)
{
// To handle tape drives & Multi-volume boundaries, use the normal
// write function, instead of doing a more optimal bulk write.

	while (count)
	{
		// If buffer full, dump it
		if (tdgbl->io_cnt <= 0)
		{
			MVOL_write(*ptr++, &tdgbl->io_cnt, &tdgbl->io_ptr);

			// One byte was written by MVOL_write
			count--;
		}

		const ULONG n = MIN(count, (ULONG) tdgbl->io_cnt);

		// Copy data to the IO buffer

		memcpy(tdgbl->io_ptr, ptr, n);
		ptr += n;

		// Skip ahead in current buffer

		count -= n;
		tdgbl->io_cnt -= n;
		tdgbl->io_ptr += n;

	}
	return ptr;
}


//____________________________________________________________
//
// We ran into an unsupported attribute.  This shouldn't happen,
// but it isn't the end of the world.
//
static void bad_attribute(int attribute, USHORT type)
{
	TEXT name[128];

	BurpGlobals* tdgbl = BurpGlobals::getSpecific();
	static const SafeArg dummy;
	fb_msg_format(NULL, burp_msg_fac, type, sizeof(name), name, dummy);
	BURP_print(80, SafeArg() << name << attribute);
	// msg 80  don't recognize %s attribute %ld -- continuing
	for (int l = get(tdgbl); l; --l)
		get(tdgbl);
}


//____________________________________________________________
//
//
static void file_not_empty()
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	tdgbl->mvol_empty_file = false;
}


//____________________________________________________________
//
// Get a numeric value from the input stream.
//
static SLONG get_numeric()
{
	SLONG value[2];

	SSHORT length = get_text((UCHAR*) value, sizeof(value));

	return gds__vax_integer(reinterpret_cast<const UCHAR*>(value), length);
}


//____________________________________________________________
//
// Move a text attribute to a string and fill.
//
static int get_text(UCHAR* text, SSHORT length)
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	ULONG l = get(tdgbl);
	length -= l;
	const ULONG l2 = l;

	if (length < 0)
	{
		BURP_error_redirect(0, 46);	// msg 46 string truncated
	}

	if (l)
	{
		do {
			*text++ = get(tdgbl);
		} while (--l);
	}

	*text = 0;

	return l2;
}


//____________________________________________________________
//
// Get specification for the next volume (tape).
// Try to open it. Return file descriptor.
//
static DESC next_volume( DESC handle, ULONG mode, bool full_buffer)
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

// We must  close the old handle before the user inserts
// another tape, or something.

#ifdef WIN_NT
	if (handle != INVALID_HANDLE_VALUE)
#else
	if (handle > -1)
#endif // WIN_NT
	{
		close_platf(handle);
	}

	if (tdgbl->action->act_action == ACT_restore_join)
	{
		tdgbl->action->act_file->fil_fd = INVALID_HANDLE_VALUE;
		if ((tdgbl->action->act_total > tdgbl->action->act_file->fil_seq) &&
			(tdgbl->action->act_file = tdgbl->action->act_file->fil_next) &&
			(tdgbl->action->act_file->fil_fd != INVALID_HANDLE_VALUE))
		{
			return tdgbl->action->act_file->fil_fd;
		}

		BURP_error_redirect(0, 50);	// msg 50 unexpected end of file on backup file
	}

// If we got here, we've got a live one... Up the volume number unless
// the old file was empty

	if (!tdgbl->mvol_empty_file)
		++tdgbl->mvol_volume_count;

	tdgbl->mvol_empty_file = true;

// Loop until we have opened a file successfully

	SCHAR new_file[MAX_FILE_NAME_SIZE];
	DESC new_desc = INVALID_HANDLE_VALUE;
	for (;;)
	{
		// We aim to keep our descriptors clean

		if (new_desc != INVALID_HANDLE_VALUE) {
			close_platf(new_desc);
			new_desc = INVALID_HANDLE_VALUE;
		}

		// Get file name to try

		prompt_for_name(new_file, sizeof(new_file));

#ifdef WIN_NT
		new_desc = MVOL_open(new_file, mode, OPEN_ALWAYS);
		if (new_desc == INVALID_HANDLE_VALUE)
#else
		new_desc = open(new_file, mode, open_mask);
		if (new_desc < 0)
#endif // WIN_NT
		{
			BURP_print(222, new_file);
			// msg 222 \n\nCould not open file name \"%s\"\n
			continue;
		}

		// If the file is to be writable, probe it, and make sure it is...

#ifdef WIN_NT
		if (mode == MODE_WRITE)
#else
		if ((O_WRONLY == (mode & O_WRONLY)) || (O_RDWR == (mode & O_RDWR)))
#endif // WIN_NT
		{
			if (!write_header(new_desc, 0L, full_buffer))
			{
				BURP_print(223, new_file);
				// msg223 \n\nCould not write to file \"%s\"\n
				continue;
			}
			else
			{
				BURP_msg_put(261, SafeArg() << tdgbl->mvol_volume_count << new_file);
				// Starting with volume #vol_count, new_file
				BURP_verbose(75, new_file);	// msg 75  creating file %s
			}
		}
		else
		{
			// File is open for read only.  Read the header.

			ULONG temp_buffer_size;
			USHORT format;
			if (!read_header(new_desc, &temp_buffer_size, &format, false))
			{
				BURP_print(224, new_file);
				continue;
			}
			else
			{
				BURP_msg_put(261, SafeArg() << tdgbl->mvol_volume_count << new_file);
				// Starting with volume #vol_count, new_file
				BURP_verbose(100, new_file);	// msg 100  opened file %s
			}
		}

		strcpy(tdgbl->mvol_old_file, new_file);
		return new_desc;
	}
}


//____________________________________________________________
//
//
static void prompt_for_name(SCHAR* name, int length)
{
	FILE*	term_in = NULL;
	FILE*	term_out =  NULL;
	TEXT	msg[BURP_MSG_GET_SIZE];

	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

// Unless we are operating as a service, stdin can't necessarily be trusted.
// Get a location to read from.
	fb_assert(!tdgbl->uSvc->isService());

	if (isatty(fileno(stdout)) || !(term_out = fopen(TERM_OUTPUT, "w")))
	{
		term_out = stdout;
	}

	if (isatty(fileno(stdin)) || !(term_in = fopen(TERM_INPUT, "r")))
	{
		term_in = stdin;
	}

// Loop until we have a file name to try

	for (;;)
	{
		// If there was an old file name, use that prompt

		if (strlen(tdgbl->mvol_old_file) > 0)
		{
			BURP_msg_get(225, msg, SafeArg() << (tdgbl->mvol_volume_count - 1) << tdgbl->mvol_old_file);
			fprintf(term_out, msg);
			BURP_msg_get(226, msg);
			// \tPress return to reopen that file, or type a new\n\tname
			// followed by return to open a different file.\n
			fprintf(term_out, msg);
		}
		else	// First volume
		{
			BURP_msg_get(227, msg);
			// Type a file name to open and hit return
			fprintf(term_out, msg);
		}
		BURP_msg_get(228, msg);	// "  Name: "
		fprintf(term_out, msg);

		fflush(term_out);
		if (fgets(name, length, term_in) == NULL)
		{
			BURP_msg_get(229, msg);
			// \n\nERROR: Backup incomplete\n
			fprintf(term_out, msg);
			BURP_exit_local(FINI_ERROR, tdgbl);
		}

		// If the user typed just a carriage return, they
		// want the old file.  If there isn't one, reprompt

		if (name[0] == '\n')
		{
			if (strlen(tdgbl->mvol_old_file) > 0)
			{
				strcpy(name, tdgbl->mvol_old_file);
				break;
			}
			else				// reprompt
				continue;
		}

		// OK, its a file name, strip the carriage return

		SCHAR* name_ptr = name;
		while (*name_ptr && *name_ptr != '\n')
		{
			name_ptr++;
		}
		*name_ptr = 0;
		break;
	}

	if (term_out != stdout) {
		fclose(term_out);
	}
	if (term_in != stdin) {
		fclose(term_in);
	}
}


//____________________________________________________________
//
// Write an attribute starting with a null terminated string.
//
static void put_asciz( SCHAR attribute, const TEXT* string)
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	SSHORT l = 0;
	for (const TEXT *p = string; *p; p++)
	{
		l++;
	}
	fb_assert(l <= MAX_UCHAR);

	put(tdgbl, attribute);
	put(tdgbl, l);
	if (l)
	{
		do {
			put(tdgbl, *string++);
		} while (--l);
	}
}


//____________________________________________________________
//
// Write a numeric value as an attribute.  The number is represented
// low byte first, high byte last, as in VAX.
//
static void put_numeric( SCHAR attribute, int value)
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	const ULONG vax_value = gds__vax_integer(reinterpret_cast<const UCHAR*>(&value), sizeof(value));
	const UCHAR* p = (UCHAR*) &vax_value;

	put(tdgbl, attribute);
	put(tdgbl, sizeof(vax_value));

	for (USHORT i = 0; i < sizeof(vax_value); i++) {
		put(tdgbl, *p++);
	}
}


//____________________________________________________________
//
// Functional description
//
static bool read_header(DESC handle, ULONG* buffer_size, USHORT* format, bool init_flag)
{
	TEXT buffer[MAX_FILE_NAME_SIZE], msg[BURP_MSG_GET_SIZE];

	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

// Headers are a version number, and a volume number

#ifndef WIN_NT
	tdgbl->mvol_io_cnt = read(handle, tdgbl->mvol_io_buffer, tdgbl->mvol_actual_buffer_size);
#else
	DWORD bytesRead = 0;
	ReadFile(handle, tdgbl->mvol_io_buffer, tdgbl->mvol_actual_buffer_size, &bytesRead, NULL);
	tdgbl->mvol_io_cnt = bytesRead;
#endif
	if (!tdgbl->mvol_io_cnt)
		BURP_error_redirect(0, 45); // maybe there's a better message

	tdgbl->mvol_io_ptr = tdgbl->mvol_io_buffer;

	int attribute = get(tdgbl);
	if (attribute != rec_burp)
		BURP_error_redirect(0, 45);
		// msg 45 expected backup description record

	int l, maxlen;
	int temp;
	TEXT* p;
	for (attribute = get(tdgbl); attribute != att_end; attribute = get(tdgbl))
	{
		switch (attribute)
		{
		case att_backup_blksize:
			{
				const ULONG temp_buffer_size = get_numeric();
				if (init_flag)
					*buffer_size = temp_buffer_size;
			}
			break;

		case att_backup_compress:
			temp = get_numeric();
			if (init_flag)
				tdgbl->gbl_sw_compress = temp != 0;
			break;

		case att_backup_date:
			l = get(tdgbl);
			if (init_flag)
			{
				p = tdgbl->gbl_backup_start_time;
				maxlen = sizeof(tdgbl->gbl_backup_start_time) - 1;
			}
			else
			{
				p = buffer;
				maxlen = sizeof(buffer) - 1;
			}
			if (l)
			{
				do {
					*p++ = get(tdgbl);
				} while (--l && --maxlen);
				// Discard elements that don't fit in the buffer, possible corrupt backup
				if (l > 0 && !maxlen)
				{
					while (l--)
						get(tdgbl);
				}
			}
			*p = 0;
			if (!init_flag && strcmp(buffer, tdgbl->gbl_backup_start_time))
			{
				BURP_msg_get(230, msg, SafeArg() << tdgbl->gbl_backup_start_time << buffer);
				// Expected backup start time %s, found %s\n
				printf(msg);
				return false;
			}
			break;

		case att_backup_file:
			l = get(tdgbl);
			if (init_flag)
			{
				p = tdgbl->mvol_db_name_buffer;
				maxlen = sizeof(tdgbl->mvol_db_name_buffer) - 1;
			}
			else
			{
				p = buffer;
				maxlen = sizeof(buffer) - 1;
			}
			if (l)
			{
				do {
					*p++ = get(tdgbl);
				} while (--l && --maxlen);
				// Discard elements that don't fit in the buffer, possible corrupt backup
				if (l > 0 && !maxlen)
				{
					while (l--)
						get(tdgbl);
				}
			}
			*p = 0;
			if (!init_flag && strcmp(buffer, tdgbl->gbl_database_file_name))
			{
				BURP_msg_get(231, msg, SafeArg() << tdgbl->gbl_database_file_name << buffer);
				// Expected backup database %s, found %s\n
				printf(msg);
				return false;
			}
			if (init_flag)
			{
				tdgbl->gbl_database_file_name = tdgbl->mvol_db_name_buffer;
			}
			break;

		case att_backup_format:
			temp = get_numeric();
			if (init_flag)
				*format = temp;
			break;

		case att_backup_transportable:
			temp = get_numeric();
			if (init_flag)
			{
				tdgbl->gbl_sw_transportable = temp != 0;
			}
			break;

		case att_backup_volume:
			temp = get_numeric();
			if (temp != tdgbl->mvol_volume_count)
			{
				BURP_msg_get(232, msg, SafeArg() << tdgbl->mvol_volume_count << temp);
				// Expected volume number %d, found volume %d\n
				printf(msg);
				return false;
			}
			break;

		default:
			bad_attribute(attribute, 59);	// msg 59 backup
		}
	}

	return true;
}


//____________________________________________________________
//
//
static bool write_header(DESC handle, ULONG backup_buffer_size, bool full_buffer)
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	if (backup_buffer_size)
	{
		tdgbl->mvol_io_header = tdgbl->mvol_io_buffer;

		put(tdgbl, rec_burp);
		put_numeric(att_backup_format, ATT_BACKUP_FORMAT);

		if (tdgbl->gbl_sw_compress)
			put_numeric(att_backup_compress, 1);

		if (tdgbl->gbl_sw_transportable)
			put_numeric(att_backup_transportable, 1);

		put_numeric(att_backup_blksize, backup_buffer_size);

		tdgbl->mvol_io_volume = tdgbl->mvol_io_ptr + 2;
		put_numeric(att_backup_volume, tdgbl->mvol_volume_count);

		put_asciz(att_backup_file, tdgbl->gbl_database_file_name);
		put_asciz(att_backup_date, tdgbl->gbl_backup_start_time);
		put(tdgbl, att_end);

		tdgbl->mvol_io_data = tdgbl->mvol_io_ptr;
	}
	else
	{
		const ULONG vax_value = gds__vax_integer(reinterpret_cast<const UCHAR*>(
											&tdgbl->mvol_volume_count),
											sizeof(tdgbl->mvol_volume_count));
		const UCHAR* p = (UCHAR*) &vax_value;
		UCHAR* q = tdgbl->mvol_io_volume;
		// CVC: Warning, do we want sizeof(int) or sizeof(some_abstract_FB_type)???
		// It seems to me we want sizeof(ULONG) for safety. => Done.
		for (size_t i = 0; i < sizeof(ULONG); i++)
		{
			*q++ = *p++;
		}
	}

	if (full_buffer)
	{
#ifdef WIN_NT
		DWORD bytes_written = 0;
		const bool err = !WriteFile(handle, tdgbl->mvol_io_header,
									tdgbl->mvol_io_buffer_size, &bytes_written, NULL);
#else
		ULONG bytes_written = write(handle, tdgbl->mvol_io_header,
							  tdgbl->mvol_io_buffer_size);
		const bool err = false;
#endif // WIN_NT

		if (err || bytes_written != tdgbl->mvol_io_buffer_size)
		{
			return false;
		}

		if (tdgbl->action->act_action == ACT_backup_split)
		{
			if (tdgbl->action->act_file->fil_length > bytes_written)
			{
				tdgbl->action->act_file->fil_length -= bytes_written;
			}
			else
			{
				tdgbl->action->act_file->fil_length = 0;
			}
		}
		tdgbl->mvol_empty_file = false;
	}

	return true;
}


//____________________________________________________________
//
// Write a header record for split operation
//
bool MVOL_split_hdr_write()
{
	TEXT buffer[HDR_SPLIT_SIZE + 1];

	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	fb_assert(tdgbl->action->act_action == ACT_backup_split);
	fb_assert(tdgbl->action->act_file->fil_fd != INVALID_HANDLE_VALUE);

	if (tdgbl->action->act_file->fil_length < HDR_SPLIT_SIZE) {
		return false;
	}

	time_t seconds = time(NULL);

	sprintf(buffer, "%s%.24s      , file No. %4d of %4d, %-27.27s",
			HDR_SPLIT_TAG, ctime(&seconds), tdgbl->action->act_file->fil_seq,
			tdgbl->action->act_total, tdgbl->action->act_file->fil_name.c_str());

#ifdef WIN_NT
	DWORD bytes_written = 0;
	WriteFile(tdgbl->action->act_file->fil_fd, buffer, HDR_SPLIT_SIZE, &bytes_written, NULL);
#else
	ULONG bytes_written = write(tdgbl->action->act_file->fil_fd, buffer, HDR_SPLIT_SIZE);
#endif // WIN_NT

	if (bytes_written != HDR_SPLIT_SIZE) {
		return false;
	}

	tdgbl->action->act_file->fil_length -= bytes_written;
	return true;
}


//____________________________________________________________
//
// Read a header record for join operation
//
bool MVOL_split_hdr_read()
{
	BurpGlobals* tdgbl = BurpGlobals::getSpecific();

	fb_assert(tdgbl->action->act_file->fil_fd != INVALID_HANDLE_VALUE);

	if (tdgbl->action && tdgbl->action->act_file &&
		(tdgbl->action->act_file->fil_fd != INVALID_HANDLE_VALUE))
	{
		TEXT buffer[HDR_SPLIT_SIZE];
		int cnt = 0;

#ifdef WIN_NT
		ReadFile(tdgbl->action->act_file->fil_fd, buffer, HDR_SPLIT_SIZE,
					reinterpret_cast<DWORD*>(&cnt), NULL);
#else
		cnt = read(tdgbl->action->act_file->fil_fd, buffer, HDR_SPLIT_SIZE);
#endif
		if ((cnt >= 0) && ((ULONG) cnt == HDR_SPLIT_SIZE) &&
			((strncmp(buffer, HDR_SPLIT_TAG, (sizeof(HDR_SPLIT_TAG) - 1)) == 0) ||
			(strncmp(buffer, HDR_SPLIT_TAG5, (sizeof(HDR_SPLIT_TAG) - 1)) == 0)))
		{
			const hdr_split* hdr = (hdr_split*) buffer;
			if ((tdgbl->action->act_file->fil_seq = atoi(hdr->hdr_split_sequence)) > 0 &&
				(tdgbl->action->act_total = atoi(hdr->hdr_split_total)) > 0 &&
				(tdgbl->action->act_file->fil_seq <= tdgbl->action->act_total))
			{
				return true;
			}
		}
	}

	return false;
}