parted-1.8.7/libparted/fs/hfs/file_plus.c - nest-learning-thermostat/5.1.7/parted - Git at Google

 /*
     libparted - a library for manipulating disk partitions
     Copyright (C) 2004, 2005, 2007 Free Software Foundation, Inc.

     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
     (at your option) any later version.

     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.

     You should have received a copy of the GNU General Public License
     along with this program; if not, write to the Free Software
     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */

 #ifndef DISCOVER_ONLY

 #include <config.h>

 #include <parted/parted.h>
 #include <parted/endian.h>
 #include <parted/debug.h>
 #include <stdint.h>

 #if ENABLE_NLS
 #  include <libintl.h>
 #  define _(String) dgettext (PACKAGE, String)
 #else
 #  define _(String) (String)
 #endif /* ENABLE_NLS */

 #include "hfs.h"
 #include "advfs_plus.h"

 #include "file_plus.h"

 /* Open the data fork of a file with its first eight extents and its CNID */
 /* CNID and ext_desc must be in disc order, sect_nb in CPU order */
 /* return null on failure */
 HfsPPrivateFile*
 hfsplus_file_open (PedFileSystem *fs, HfsPNodeID CNID,
 		   HfsPExtDataRec ext_desc, PedSector sect_nb)
 {
 	HfsPPrivateFile* file;

 	file = (HfsPPrivateFile*) ped_malloc (sizeof (HfsPPrivateFile));
 	if (!file) return NULL;

 	file->fs = fs;
 	file->sect_nb = sect_nb;
 	file->CNID = CNID;
 	memcpy(file->first, ext_desc, sizeof (HfsPExtDataRec));
 	file->start_cache = 0;

 	return file;
 }

 /* Close an HFS+ file */
 void
 hfsplus_file_close (HfsPPrivateFile* file)
 {
 	ped_free (file);
 }

 /* warning : only works on data forks */
 static int
 hfsplus_get_extent_containing (HfsPPrivateFile* file, unsigned int block,
 			       HfsPExtDataRec cache, uint32_t* ptr_start_cache)
 {
 	uint8_t			record[sizeof (HfsPExtentKey)
 				       + sizeof (HfsPExtDataRec)];
 	HfsPExtentKey		search;
 	HfsPExtentKey*		ret_key = (HfsPExtentKey*) record;
 	HfsPExtDescriptor*	ret_cache = (HfsPExtDescriptor*)
 					      (record + sizeof (HfsPExtentKey));
 	HfsPPrivateFSData* 	priv_data = (HfsPPrivateFSData*)
 						file->fs->type_specific;

 	search.key_length = PED_CPU_TO_BE16 (sizeof (HfsPExtentKey) - 2);
 	search.type = HFS_DATA_FORK;
 	search.pad = 0;
 	search.file_ID = file->CNID;
 	search.start = PED_CPU_TO_BE32 (block);

 	if (!hfsplus_btree_search (priv_data->extents_file,
 				   (HfsPPrivateGenericKey*) &search,
 				   record, sizeof (record), NULL))
 		return 0;

 	if (ret_key->file_ID != search.file_ID || ret_key->type != search.type)
 		return 0;

 	memcpy (cache, ret_cache, sizeof(HfsPExtDataRec));
 	*ptr_start_cache = PED_BE32_TO_CPU (ret_key->start);

 	return 1;
 }

 /* find a sub extent contained in the desired area */
 /* and with the same starting point */
 /* return 0 in sector_count on error, or the physical area */
 /* on the volume corresponding to the logical area in the file */
 static HfsPPrivateExtent
 hfsplus_file_find_extent (HfsPPrivateFile* file, PedSector sector,
 			  unsigned int nb)
 {
 	HfsPPrivateExtent ret = {0,0};
 	HfsPPrivateFSData* priv_data = (HfsPPrivateFSData*)
 					file->fs->type_specific;
 	unsigned int	sect_by_block = PED_BE32_TO_CPU (
 					    priv_data->vh->block_size)
 					/ PED_SECTOR_SIZE_DEFAULT;
 	unsigned int	i, s, vol_block, size;
 	PedSector	sect_size;
 	unsigned int	block  = sector / sect_by_block;
 	unsigned int	offset = sector % sect_by_block;

 	/* in the 8 first extent */
 	for (s = 0, i = 0; i < HFSP_EXT_NB; i++) {
 		if ((block >= s) && (block < s + PED_BE32_TO_CPU (
 						file->first[i].block_count))) {
 			vol_block = (block - s)
 				    + PED_BE32_TO_CPU (file->first[i]
 						       .start_block);
 			size = PED_BE32_TO_CPU (file->first[i].block_count)
 				+ s - block;
 			goto plus_sector_found;
 		}
 		s += PED_BE32_TO_CPU (file->first[i].block_count);
 	}

 	/* in the 8 cached extent */
 	if (file->start_cache && block >= file->start_cache)
 	for (s = file->start_cache, i = 0; i < HFSP_EXT_NB; i++) {
 		if ((block >= s) && (block < s + PED_BE32_TO_CPU (
 						file->cache[i].block_count))) {
 			vol_block = (block - s)
 				    + PED_BE32_TO_CPU (file->cache[i]
 						       .start_block);
 			size = PED_BE32_TO_CPU (file->cache[i].block_count)
 				+ s - block;
 			goto plus_sector_found;
 		}
 		s += PED_BE32_TO_CPU (file->cache[i].block_count);
 	}

 	/* update cache */
 	if (!hfsplus_get_extent_containing (file, block, file->cache,
 					    &(file->start_cache))) {
 		ped_exception_throw (
 			PED_EXCEPTION_WARNING,
 			PED_EXCEPTION_CANCEL,
 			_("Could not update the extent cache for HFS+ file "
 			  "with CNID %X."),
 			PED_BE32_TO_CPU(file->CNID));
 		return ret; /* ret == {0,0} */
 	}

 	/* ret == {0,0} */
 	PED_ASSERT(file->start_cache && block >= file->start_cache, return ret);

 	for (s = file->start_cache, i = 0; i < HFSP_EXT_NB; i++) {
 		if ((block >= s) && (block < s + PED_BE32_TO_CPU (
 						file->cache[i].block_count))) {
 			vol_block = (block - s)
 				    + PED_BE32_TO_CPU (file->cache[i]
 						       .start_block);
 			size = PED_BE32_TO_CPU (file->cache[i].block_count)
 				+ s - block;
 			goto plus_sector_found;
 		}
 		s += PED_BE32_TO_CPU (file->cache[i].block_count);
 	}

 	return ret;

 plus_sector_found:
 	sect_size = (PedSector) size * sect_by_block - offset;
 	ret.start_sector = vol_block * sect_by_block + offset;
 	ret.sector_count = (sect_size < nb) ? sect_size : nb;
 	return ret;
 }

 int
 hfsplus_file_read(HfsPPrivateFile* file, void *buf, PedSector sector,
 		  unsigned int nb)
 {
 	HfsPPrivateExtent phy_area;
 	HfsPPrivateFSData* priv_data = (HfsPPrivateFSData*)
 					file->fs->type_specific;
         char *b = buf;

 	if (sector+nb < sector /* detect overflow */
 	    || sector+nb > file->sect_nb) /* out of file */ {
 		ped_exception_throw (
 			PED_EXCEPTION_ERROR,
 			PED_EXCEPTION_CANCEL,
 			_("Trying to read HFS+ file with CNID %X behind EOF."),
 			PED_BE32_TO_CPU(file->CNID));
 		return 0;
 	}

 	while (nb) {
 		phy_area = hfsplus_file_find_extent(file, sector, nb);
 		if (phy_area.sector_count == 0) {
 			ped_exception_throw (
 				PED_EXCEPTION_ERROR,
 				PED_EXCEPTION_CANCEL,
 				_("Could not find sector %lli of HFS+ file "
 				  "with CNID %X."),
 				sector, PED_BE32_TO_CPU(file->CNID));
 			return 0;
 		}
                 if (!ped_geometry_read(priv_data->plus_geom, b,
 				       phy_area.start_sector,
 				       phy_area.sector_count))
 			return 0;

 		nb -= phy_area.sector_count; /* < nb anyway ... */
 		sector += phy_area.sector_count;
                 b += phy_area.sector_count * PED_SECTOR_SIZE_DEFAULT;
 	}

 	return 1;
 }

 int
 hfsplus_file_write(HfsPPrivateFile* file, void *buf, PedSector sector,
 		  unsigned int nb)
 {
 	HfsPPrivateExtent phy_area;
 	HfsPPrivateFSData* priv_data = (HfsPPrivateFSData*)
 					file->fs->type_specific;
         char *b = buf;

 	if (sector+nb < sector /* detect overflow */
 	    || sector+nb > file->sect_nb) /* out of file */ {
 		ped_exception_throw (
 			PED_EXCEPTION_ERROR,
 			PED_EXCEPTION_CANCEL,
 			_("Trying to write HFS+ file with CNID %X behind EOF."),
 			PED_BE32_TO_CPU(file->CNID));
 		return 0;
 	}

 	while (nb) {
 		phy_area = hfsplus_file_find_extent(file, sector, nb);
 		if (phy_area.sector_count == 0) {
 			ped_exception_throw (
 				PED_EXCEPTION_ERROR,
 				PED_EXCEPTION_CANCEL,
 				_("Could not find sector %lli of HFS+ file "
 				  "with CNID %X."),
 				sector, PED_BE32_TO_CPU(file->CNID));
 			return 0;
 		}
                 if (!ped_geometry_write(priv_data->plus_geom, b,
 				       phy_area.start_sector,
 				       phy_area.sector_count))
 			return 0;

 		nb -= phy_area.sector_count; /* < nb anyway ... */
 		sector += phy_area.sector_count;
                 b += phy_area.sector_count * PED_SECTOR_SIZE_DEFAULT;
 	}

 	return 1;
 }

 #endif /* !DISCOVER_ONLY */
	/*
	libparted - a library for manipulating disk partitions
	Copyright (C) 2004, 2005, 2007 Free Software Foundation, Inc.

	This program is free software; you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation; either version 2 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to the Free Software
	Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
	*/

	#ifndef DISCOVER_ONLY

	#include <config.h>

	#include <parted/parted.h>
	#include <parted/endian.h>
	#include <parted/debug.h>
	#include <stdint.h>

	#if ENABLE_NLS
	# include <libintl.h>
	# define _(String) dgettext (PACKAGE, String)
	#else
	# define _(String) (String)
	#endif /* ENABLE_NLS */

	#include "hfs.h"
	#include "advfs_plus.h"

	#include "file_plus.h"

	/* Open the data fork of a file with its first eight extents and its CNID */
	/* CNID and ext_desc must be in disc order, sect_nb in CPU order */
	/* return null on failure */
	HfsPPrivateFile*
	hfsplus_file_open (PedFileSystem *fs, HfsPNodeID CNID,
	HfsPExtDataRec ext_desc, PedSector sect_nb)
	{
	HfsPPrivateFile* file;

	file = (HfsPPrivateFile*) ped_malloc (sizeof (HfsPPrivateFile));
	if (!file) return NULL;

	file->fs = fs;
	file->sect_nb = sect_nb;
	file->CNID = CNID;
	memcpy(file->first, ext_desc, sizeof (HfsPExtDataRec));
	file->start_cache = 0;

	return file;
	}

	/* Close an HFS+ file */
	void
	hfsplus_file_close (HfsPPrivateFile* file)
	{
	ped_free (file);
	}

	/* warning : only works on data forks */
	static int
	hfsplus_get_extent_containing (HfsPPrivateFile* file, unsigned int block,
	HfsPExtDataRec cache, uint32_t* ptr_start_cache)
	{
	uint8_t record[sizeof (HfsPExtentKey)
	+ sizeof (HfsPExtDataRec)];
	HfsPExtentKey search;
	HfsPExtentKey* ret_key = (HfsPExtentKey*) record;
	HfsPExtDescriptor* ret_cache = (HfsPExtDescriptor*)
	(record + sizeof (HfsPExtentKey));
	HfsPPrivateFSData* priv_data = (HfsPPrivateFSData*)
	file->fs->type_specific;

	search.key_length = PED_CPU_TO_BE16 (sizeof (HfsPExtentKey) - 2);
	search.type = HFS_DATA_FORK;
	search.pad = 0;
	search.file_ID = file->CNID;
	search.start = PED_CPU_TO_BE32 (block);

	if (!hfsplus_btree_search (priv_data->extents_file,
	(HfsPPrivateGenericKey*) &search,
	record, sizeof (record), NULL))
	return 0;

	if (ret_key->file_ID != search.file_ID \|\| ret_key->type != search.type)
	return 0;

	memcpy (cache, ret_cache, sizeof(HfsPExtDataRec));
	*ptr_start_cache = PED_BE32_TO_CPU (ret_key->start);

	return 1;
	}

	/* find a sub extent contained in the desired area */
	/* and with the same starting point */
	/* return 0 in sector_count on error, or the physical area */
	/* on the volume corresponding to the logical area in the file */
	static HfsPPrivateExtent
	hfsplus_file_find_extent (HfsPPrivateFile* file, PedSector sector,
	unsigned int nb)
	{
	HfsPPrivateExtent ret = {0,0};
	HfsPPrivateFSData* priv_data = (HfsPPrivateFSData*)
	file->fs->type_specific;
	unsigned int sect_by_block = PED_BE32_TO_CPU (
	priv_data->vh->block_size)
	/ PED_SECTOR_SIZE_DEFAULT;
	unsigned int i, s, vol_block, size;
	PedSector sect_size;
	unsigned int block = sector / sect_by_block;
	unsigned int offset = sector % sect_by_block;

	/* in the 8 first extent */
	for (s = 0, i = 0; i < HFSP_EXT_NB; i++) {
	if ((block >= s) && (block < s + PED_BE32_TO_CPU (
	file->first[i].block_count))) {
	vol_block = (block - s)
	+ PED_BE32_TO_CPU (file->first[i]
	.start_block);
	size = PED_BE32_TO_CPU (file->first[i].block_count)
	+ s - block;
	goto plus_sector_found;
	}
	s += PED_BE32_TO_CPU (file->first[i].block_count);
	}

	/* in the 8 cached extent */
	if (file->start_cache && block >= file->start_cache)
	for (s = file->start_cache, i = 0; i < HFSP_EXT_NB; i++) {
	if ((block >= s) && (block < s + PED_BE32_TO_CPU (
	file->cache[i].block_count))) {
	vol_block = (block - s)
	+ PED_BE32_TO_CPU (file->cache[i]
	.start_block);
	size = PED_BE32_TO_CPU (file->cache[i].block_count)
	+ s - block;
	goto plus_sector_found;
	}
	s += PED_BE32_TO_CPU (file->cache[i].block_count);
	}

	/* update cache */
	if (!hfsplus_get_extent_containing (file, block, file->cache,
	&(file->start_cache))) {
	ped_exception_throw (
	PED_EXCEPTION_WARNING,
	PED_EXCEPTION_CANCEL,
	_("Could not update the extent cache for HFS+ file "
	"with CNID %X."),
	PED_BE32_TO_CPU(file->CNID));
	return ret; /* ret == {0,0} */
	}

	/* ret == {0,0} */
	PED_ASSERT(file->start_cache && block >= file->start_cache, return ret);

	for (s = file->start_cache, i = 0; i < HFSP_EXT_NB; i++) {
	if ((block >= s) && (block < s + PED_BE32_TO_CPU (
	file->cache[i].block_count))) {
	vol_block = (block - s)
	+ PED_BE32_TO_CPU (file->cache[i]
	.start_block);
	size = PED_BE32_TO_CPU (file->cache[i].block_count)
	+ s - block;
	goto plus_sector_found;
	}
	s += PED_BE32_TO_CPU (file->cache[i].block_count);
	}

	return ret;

	plus_sector_found:
	sect_size = (PedSector) size * sect_by_block - offset;
	ret.start_sector = vol_block * sect_by_block + offset;
	ret.sector_count = (sect_size < nb) ? sect_size : nb;
	return ret;
	}

	int
	hfsplus_file_read(HfsPPrivateFile* file, void *buf, PedSector sector,
	unsigned int nb)
	{
	HfsPPrivateExtent phy_area;
	HfsPPrivateFSData* priv_data = (HfsPPrivateFSData*)
	file->fs->type_specific;
	char *b = buf;

	if (sector+nb < sector /* detect overflow */
	\|\| sector+nb > file->sect_nb) /* out of file */ {
	ped_exception_throw (
	PED_EXCEPTION_ERROR,
	PED_EXCEPTION_CANCEL,
	_("Trying to read HFS+ file with CNID %X behind EOF."),
	PED_BE32_TO_CPU(file->CNID));
	return 0;
	}

	while (nb) {
	phy_area = hfsplus_file_find_extent(file, sector, nb);
	if (phy_area.sector_count == 0) {
	ped_exception_throw (
	PED_EXCEPTION_ERROR,
	PED_EXCEPTION_CANCEL,
	_("Could not find sector %lli of HFS+ file "
	"with CNID %X."),
	sector, PED_BE32_TO_CPU(file->CNID));
	return 0;
	}
	if (!ped_geometry_read(priv_data->plus_geom, b,
	phy_area.start_sector,
	phy_area.sector_count))
	return 0;

	nb -= phy_area.sector_count; /* < nb anyway ... */
	sector += phy_area.sector_count;
	b += phy_area.sector_count * PED_SECTOR_SIZE_DEFAULT;
	}

	return 1;
	}

	int
	hfsplus_file_write(HfsPPrivateFile* file, void *buf, PedSector sector,
	unsigned int nb)
	{
	HfsPPrivateExtent phy_area;
	HfsPPrivateFSData* priv_data = (HfsPPrivateFSData*)
	file->fs->type_specific;
	char *b = buf;

	if (sector+nb < sector /* detect overflow */
	\|\| sector+nb > file->sect_nb) /* out of file */ {
	ped_exception_throw (
	PED_EXCEPTION_ERROR,
	PED_EXCEPTION_CANCEL,
	_("Trying to write HFS+ file with CNID %X behind EOF."),
	PED_BE32_TO_CPU(file->CNID));
	return 0;
	}

	while (nb) {
	phy_area = hfsplus_file_find_extent(file, sector, nb);
	if (phy_area.sector_count == 0) {
	ped_exception_throw (
	PED_EXCEPTION_ERROR,
	PED_EXCEPTION_CANCEL,
	_("Could not find sector %lli of HFS+ file "
	"with CNID %X."),
	sector, PED_BE32_TO_CPU(file->CNID));
	return 0;
	}
	if (!ped_geometry_write(priv_data->plus_geom, b,
	phy_area.start_sector,
	phy_area.sector_count))
	return 0;

	nb -= phy_area.sector_count; /* < nb anyway ... */
	sector += phy_area.sector_count;
	b += phy_area.sector_count * PED_SECTOR_SIZE_DEFAULT;
	}

	return 1;
	}

	#endif /* !DISCOVER_ONLY */