gparted/src/FS_Info.cc

302 lines
10 KiB
C++

/* Copyright (C) 2008, 2009, 2010 Curtis Gedak
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include "FS_Info.h"
#include "BlockSpecial.h"
#include "Utils.h"
#include <iostream>
#include <glibmm/ustring.h>
#include <glibmm/miscutils.h>
#include <glibmm/shell.h>
#include <vector>
namespace GParted
{
//initialize static data elements
bool FS_Info::fs_info_cache_initialized = false ;
bool FS_Info::blkid_found = false ;
// Assume workaround is needed just in case determination fails and as
// it only costs a fraction of a second to run blkid command again.
bool FS_Info::need_blkid_vfat_cache_update_workaround = true;
// Vector of file system information.
// E.g.
// (Note BS(path) is a short hand for constructor BlockSpecial(path)).
// //path , type , sec_type, uuid , have_label, label
// [{BS("/dev/sda") , "" , "" , "" , false , "" },
// {BS("/dev/sda1"), "xfs" , "" , "f828ee8c-1e16-4ca9-b234-e4949dcd4bd1" , false , "" },
// {BS("/dev/sda2"), "LVM2_member", "" , "p31pR5-qPLm-YICz-O09i-sB4u-mAH2-GVSNWG", false , "" },
// {BS("/dev/sdb") , "" , "" , "" , false , "" },
// {BS("/dev/sdb1"), "ext3" , "ext2" , "f218c3b8-237e-4fbe-92c5-76623bba4062" , true , "test-ext3" },
// {BS("/dev/sdb2"), "vfat" , "msdos" , "9F87-1061" , true , "TEST-FAT16"},
// {BS("/dev/sdb3"), "" , "" , "" , false , "" }
// ]
std::vector<FS_Entry> FS_Info::fs_info_cache;
void FS_Info::clear_cache()
{
set_commands_found();
fs_info_cache.clear();
fs_info_cache_initialized = true;
}
void FS_Info::load_cache_for_paths(const std::vector<Glib::ustring>& paths)
{
if (not_initialised_then_error())
return;
run_blkid_load_cache(paths);
}
// Retrieve the file system type for the path
Glib::ustring FS_Info::get_fs_type( const Glib::ustring & path )
{
if (not_initialised_then_error())
return "";
const FS_Entry & fs_entry = get_cache_entry_by_path( path );
Glib::ustring fs_type = fs_entry.type;
Glib::ustring fs_sec_type = fs_entry.sec_type;
// If vfat, decide whether fat16 or fat32
if ( fs_type == "vfat" )
{
if ( need_blkid_vfat_cache_update_workaround )
{
// Blkid cache does not correctly add and remove SEC_TYPE when
// overwriting FAT16 and FAT32 file systems with each other, so
// prevents correct identification. Run blkid command again,
// bypassing the the cache to get the correct results.
Glib::ustring output;
Glib::ustring error;
if ( ! Utils::execute_command( "blkid -c /dev/null " + Glib::shell_quote( path ),
output, error, true ) )
fs_sec_type = Utils::regexp_label( output, " SEC_TYPE=\"([^\"]*)\"" );
}
if ( fs_sec_type == "msdos" )
fs_type = "fat16";
else
fs_type = "fat32";
}
return fs_type;
}
// Retrieve the label and set found indicator for the path
Glib::ustring FS_Info::get_label( const Glib::ustring & path, bool & found )
{
if (not_initialised_then_error())
{
found = false;
return "";
}
BlockSpecial bs = BlockSpecial( path );
for ( unsigned int i = 0 ; i < fs_info_cache.size() ; i ++ )
if ( bs == fs_info_cache[i].path )
{
if ( fs_info_cache[i].have_label || fs_info_cache[i].type == "" )
{
// Already have the label or this is a blank cache entry
// for a whole disk device containing a partition table,
// so no label.
found = fs_info_cache[i].have_label;
return fs_info_cache[i].label;
}
// Run blkid to get the label for this one partition, update the
// cache and return the found label.
found = run_blkid_update_cache_one_label( fs_info_cache[i] );
return fs_info_cache[i].label;
}
found = false;
return "";
}
// Retrieve the uuid given for the path
Glib::ustring FS_Info::get_uuid( const Glib::ustring & path )
{
if (not_initialised_then_error())
return "";
const FS_Entry & fs_entry = get_cache_entry_by_path( path );
return fs_entry.uuid;
}
// Retrieve the path given the uuid
Glib::ustring FS_Info::get_path_by_uuid( const Glib::ustring & uuid )
{
if (not_initialised_then_error())
return "";
for ( unsigned int i = 0 ; i < fs_info_cache.size() ; i ++ )
if ( uuid == fs_info_cache[i].uuid )
return fs_info_cache[i].path.m_name;
return "";
}
// Retrieve the path given the label
Glib::ustring FS_Info::get_path_by_label( const Glib::ustring & label )
{
if (not_initialised_then_error())
return "";
update_fs_info_cache_all_labels();
for ( unsigned int i = 0 ; i < fs_info_cache.size() ; i ++ )
if ( label == fs_info_cache[i].label )
return fs_info_cache[i].path.m_name;
return "";
}
// Private methods
bool FS_Info::not_initialised_then_error()
{
if (! fs_info_cache_initialized)
std::cerr << "GParted Bug: FS_Info (blkid) cache not loaded before use" << std::endl;
return ! fs_info_cache_initialized;
}
void FS_Info::set_commands_found()
{
//Set status of commands found
blkid_found = (! Glib::find_program_in_path( "blkid" ) .empty() ) ;
if ( blkid_found )
{
// Blkid from util-linux before 2.23 has a cache update bug which prevents
// correct identification between FAT16 and FAT32 when overwriting one
// with the other. Detect the need for a workaround.
Glib::ustring output, error;
Utils::execute_command( "blkid -v", output, error, true );
Glib::ustring blkid_version = Utils::regexp_label( output, "blkid.* ([0-9\\.]+) " );
int blkid_major_ver = 0;
int blkid_minor_ver = 0;
if ( sscanf( blkid_version.c_str(), "%d.%d", &blkid_major_ver, &blkid_minor_ver ) == 2 )
{
need_blkid_vfat_cache_update_workaround =
( blkid_major_ver < 2 ||
( blkid_major_ver == 2 && blkid_minor_ver < 23 ) );
}
}
}
const FS_Entry & FS_Info::get_cache_entry_by_path( const Glib::ustring & path )
{
BlockSpecial bs = BlockSpecial( path );
for ( unsigned int i = 0 ; i < fs_info_cache.size() ; i ++ )
if ( bs == fs_info_cache[i].path )
return fs_info_cache[i];
static FS_Entry not_found = {BlockSpecial(), "", "", "", false, ""};
return not_found;
}
void FS_Info::run_blkid_load_cache(const std::vector<Glib::ustring>& paths)
{
// Parse blkid output line by line extracting mandatory field: path and optional
// fields: type, sec_type, uuid. Label is not extracted here because of blkid's
// default non-reversible encoding of non printable ASCII bytes.
// Example command:
// blkid /dev/sda /dev/sda1 /dev/sda2 /dev/sdb /dev/sdb1 /dev/sdb2 /dev/sdb3
// Example output:
// /dev/sda: PTUUID="5012fb1f" PTTYPE="dos"
// /dev/sda1: UUID="f828ee8c-1e16-4ca9-b234-e4949dcd4bd1" TYPE="xfs"
// /dev/sda2: UUID="p31pR5-qPLm-YICz-O09i-sB4u-mAH2-GVSNWG" TYPE="LVM2_member"
// /dev/sdb: PTUUID="f57595e1-c0ae-40ee-be64-00851b2a9977" PTTYPE="gpt"
// /dev/sdb1: LABEL="test-ext3" UUID="f218c3b8-237e-4fbe-92c5-76623bba4062" SEC_TYPE="ext2" TYPE="ext3" PARTUUID="71b3e059-30c5-492e-a526-9251dff7bbeb"
// /dev/sdb2: SEC_TYPE="msdos" LABEL="TEST-FAT16" UUID="9F87-1061" TYPE="vfat" PARTUUID="9d07ad9a-d468-428f-9bfd-724f5efae4fb"
// /dev/sdb3: PARTUUID="bb8438e1-d9f1-45d3-9888-e990b598900d"
if (! blkid_found)
return;
Glib::ustring cmd = "blkid";
for (unsigned int i = 0; i < paths.size(); i++)
cmd.append(" " + Glib::shell_quote(paths[i]));
Glib::ustring output;
Glib::ustring error;
if (Utils::execute_command(cmd, output, error, true) != 0)
return;
std::vector<Glib::ustring> lines;
Utils::split(output, lines, "\n");
for (unsigned int i = 0; i < lines.size(); i++)
{
FS_Entry fs_entry = {BlockSpecial(), "", "", "", false, ""};
Glib::ustring entry_path = Utils::regexp_label(lines[i], "^(.*): ");
if (entry_path.length() > 0)
{
fs_entry.path = BlockSpecial(entry_path);
fs_entry.type = Utils::regexp_label(lines[i], " TYPE=\"([^\"]*)\"");
fs_entry.sec_type = Utils::regexp_label(lines[i], " SEC_TYPE=\"([^\"]*)\"");
fs_entry.uuid = Utils::regexp_label(lines[i], " UUID=\"([^\"]*)\"");
fs_info_cache.push_back(fs_entry);
}
}
return;
}
void FS_Info::update_fs_info_cache_all_labels()
{
if ( ! blkid_found )
return;
// For all cache entries which are file systems but don't yet have a label load it
// now.
for ( unsigned int i = 0 ; i < fs_info_cache.size() ; i ++ )
if ( fs_info_cache[i].type != "" && ! fs_info_cache[i].have_label )
run_blkid_update_cache_one_label( fs_info_cache[i] );
}
bool FS_Info::run_blkid_update_cache_one_label( FS_Entry & fs_entry )
{
if ( ! blkid_found )
return false;
// (#786502) Run a separate blkid execution for a single partition to get the
// label without blkid's default non-reversible encoding.
Glib::ustring output;
Glib::ustring error;
bool success = ! Utils::execute_command( "blkid -o value -s LABEL " + Glib::shell_quote( fs_entry.path.m_name ),
output, error, true );
if ( ! success )
return false;
// Output from blkid is either the label with a trailing new line character or
// zero bytes when the file system has no label. Update the cache entry in both
// cases as the label was successfully read even if it didn't exist so is zero
// characters long.
fs_entry.have_label = true;
fs_entry.label = Utils::trim_trailing_new_line(output);
return true;
}
}//GParted