/**************************************************************/

/*  tpax: a topological pax implementation                    */

/*  Copyright (C) 2020--2024  SysDeer Technologies, LLC       */

/*  Released under GPLv2 and GPLv3; see COPYING.TPAX.         */

/**************************************************************/

#include <tpax/tpax.h>

#include "tpax_driver_impl.h"

#include "tpax_errinfo_impl.h"

#include "tpax_visibility_impl.h"

static int tpax_archive_append_memory_data(

	int                             fdout,

	void *                          buf,

	ssize_t                         nbytes)

{

	ssize_t ret;

	char  * ch;

	for (ch=buf; nbytes; ch+=ret) {

		ret = write(fdout,ch,nbytes);

		while ((ret < 0) && (errno == EINTR))

			ret = write(fdout,ch,nbytes);

		if (ret < 0)

			return ret;

		nbytes -= ret;

	}

	return 0;

}

static int tpax_archive_append_pad(

	const struct tpax_driver_ctx *  dctx,

	int                             fdout,

	const struct stat *             st)

{

	int     ret;

	off_t   cpos;

	ssize_t nbytes;

	char    buf[512];

	nbytes  = st->st_size;

	nbytes += 0x1ff;

	nbytes |= 0x1ff;

	nbytes ^= 0x1ff;

	nbytes -= st->st_size;

	memset(buf,0,nbytes);

	cpos  = tpax_get_driver_cpos(dctx);

	cpos += st->st_size + nbytes;

	if (!(ret = tpax_archive_append_memory_data(fdout,buf,nbytes)))

		tpax_set_driver_cpos(dctx,cpos);

	return ret;

}

int tpax_archive_seal(const struct tpax_driver_ctx * dctx)

{

	int     fdout;

	off_t   cpos;

	ssize_t nbytes;

	ssize_t nwritten;

	ssize_t blksize;

	char    buf[512];

	blksize = tpax_get_archive_block_size(dctx);

	cpos    = tpax_get_driver_cpos(dctx);

	if (cpos % 512)

		return TPAX_CUSTOM_ERROR(dctx,TPAX_ERR_FLOW_ERROR);

	fdout = tpax_driver_fdout(dctx);

	memset(buf,0,sizeof(buf));

	switch (cpos % blksize) {

		case 0:

			nbytes = cpos + blksize;

			break;

		default:

			nbytes  = cpos / blksize;

			nbytes *= blksize;

			nbytes += blksize;

			if (nbytes-cpos == 512)

				nbytes += blksize;

	}

	for (nwritten=cpos; nwritten

		if (tpax_archive_append_memory_data(fdout,buf,512) < 0)

			return TPAX_SYSTEM_ERROR(dctx);

		tpax_set_driver_cpos(dctx,nwritten);

	}

	(void)tpax_archive_append_pad;

	return 0;

}