gparted/src/Mount_Info.cc

260 lines
8.8 KiB
C++

/* Copyright (C) 2016 Mike Fleetwood
*
* 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 "Mount_Info.h"
#include "FS_Info.h"
#include "Utils.h"
#include <glibmm/ustring.h>
#include <glibmm/fileutils.h>
#include <stdio.h>
#include <limits.h>
#include <stdlib.h>
#include <mntent.h>
#include <string>
#include <fstream>
namespace GParted
{
// Associative array mapping currently mounted devices to one or more mount points.
// E.g.
// // readonly, mountpoints
// mount_info[BlockSpecial("/dev/sda1")] -> {false , ["/boot"] }
// mount_info[BlockSpecial("/dev/sda2")] -> {false , [""] } // swap
// mount_info[BlockSpecial("/dev/sda3")] -> {false , ["/"] }
// mount_info[BlockSpecial("/dev/sr0")] -> {true , ["/run/media/user/GParted-live"]}
static Mount_Info::MountMapping mount_info;
// Associative array mapping configured devices to one or more mount points read from
// /etc/fstab. E.g.
// // readonly, mountpoints
// fstab_info[BlockSpecial("/dev/sda1")] -> {false ,["/boot"]}
// fstab_info[BlockSpecial("/dev/sda3")] -> {false ,["/"] }
static Mount_Info::MountMapping fstab_info;
void Mount_Info::load_cache()
{
mount_info.clear();
fstab_info.clear();
read_mountpoints_from_file( "/proc/mounts", mount_info );
read_mountpoints_from_file_swaps( "/proc/swaps", mount_info );
if ( ! have_rootfs_dev( mount_info ) )
// Old distributions only contain 'rootfs' and '/dev/root' device names
// for the / (root) file system in /proc/mounts with '/dev/root' being a
// block device rather than a symlink to the true device. This prevents
// identification, and therefore busy detection, of the device containing
// the / (root) file system. Used to read /etc/mtab to get the root file
// system device name, but this contains an out of date device name after
// the mounting device has been dynamically removed from a multi-device
// btrfs, thus identifying the wrong device as busy. Instead fall back
// to reading mounted file systems from the output of the mount command,
// but only when required.
read_mountpoints_from_mount_command( mount_info );
read_mountpoints_from_file( "/etc/fstab", fstab_info );
// Sort the mount points and remove duplicates ... (no need to do this for fstab_info)
MountMapping::iterator iter_mp;
for ( iter_mp = mount_info.begin() ; iter_mp != mount_info.end() ; ++ iter_mp )
{
std::sort( iter_mp->second.mountpoints.begin(), iter_mp->second.mountpoints.end() );
iter_mp->second.mountpoints.erase(
std::unique( iter_mp->second.mountpoints.begin(), iter_mp->second.mountpoints.end() ),
iter_mp->second.mountpoints.end() );
}
}
// Return whether the device path, such as /dev/sda3, is mounted or not
bool Mount_Info::is_dev_mounted( const Glib::ustring & path )
{
return is_dev_mounted( BlockSpecial( path ) );
}
// Return whether the BlockSpecial object, such as {"/dev/sda3", 8, 3}, is mounted or not
bool Mount_Info::is_dev_mounted( const BlockSpecial & bs )
{
MountMapping::const_iterator iter_mp = mount_info.find( bs );
return iter_mp != mount_info.end();
}
// Return whether the device path, such as /dev/sda3, is mounted read-only or not
bool Mount_Info::is_dev_mounted_readonly( const Glib::ustring & path )
{
return is_dev_mounted_readonly( BlockSpecial( path ) );
}
// Return whether the BlockSpecial object, such as {"/dev/sda3", 8, 3}, is mounted read-only or not
bool Mount_Info::is_dev_mounted_readonly( const BlockSpecial & bs )
{
MountMapping::const_iterator iter_mp = mount_info.find( bs );
if ( iter_mp == mount_info.end() )
return false;
return iter_mp->second.readonly;
}
std::vector<Glib::ustring> Mount_Info::get_all_mountpoints()
{
MountMapping::const_iterator iter_mp;
std::vector<Glib::ustring> mountpoints;
for ( iter_mp = mount_info.begin() ; iter_mp != mount_info.end() ; ++ iter_mp )
mountpoints.insert( mountpoints.end(),
iter_mp->second.mountpoints.begin(), iter_mp->second.mountpoints.end() );
return mountpoints;
}
const std::vector<Glib::ustring> & Mount_Info::get_mounted_mountpoints( const Glib::ustring & path )
{
return find( mount_info, path ).mountpoints;
}
const std::vector<Glib::ustring> & Mount_Info::get_fstab_mountpoints( const Glib::ustring & path )
{
return find( fstab_info, path ).mountpoints;
}
// Private methods
void Mount_Info::read_mountpoints_from_file( const Glib::ustring & filename, MountMapping & map )
{
FILE* fp = setmntent( filename .c_str(), "r" );
if ( fp == NULL )
return;
struct mntent* p = NULL;
while ( ( p = getmntent( fp ) ) != NULL )
{
Glib::ustring node = p->mnt_fsname;
Glib::ustring mountpoint = p->mnt_dir;
Glib::ustring uuid = Utils::regexp_label( node, "^UUID=(.*)" );
if ( ! uuid.empty() )
node = FS_Info::get_path_by_uuid( uuid );
Glib::ustring label = Utils::regexp_label( node, "^LABEL=(.*)" );
if ( ! label.empty() )
node = FS_Info::get_path_by_label( label );
if ( ! node.empty() )
add_mountpoint_entry( map, node, mountpoint, parse_readonly_flag( p->mnt_opts ) );
}
endmntent( fp );
}
void Mount_Info::add_mountpoint_entry( MountMapping & map,
Glib::ustring & node,
Glib::ustring & mountpoint,
bool readonly )
{
// Only add node path if mount point exists
if ( file_test( mountpoint, Glib::FILE_TEST_EXISTS ) )
{
// Map::operator[] default constructs MountEntry for new keys (nodes).
MountEntry & mountentry = map[BlockSpecial( node )];
mountentry.readonly = mountentry.readonly || readonly;
mountentry.mountpoints.push_back( mountpoint );
}
}
// Parse file system mount options string into read-only boolean
// E.g. "ro,relatime" -> true
// "rw,seclabel,relatime,attr2,inode64,noquota" -> false
bool Mount_Info::parse_readonly_flag( const Glib::ustring & str )
{
std::vector<Glib::ustring> mntopts;
Utils::split( str, mntopts, "," );
for ( unsigned int i = 0 ; i < mntopts.size() ; i ++ )
{
if ( mntopts[i] == "rw" )
return false;
else if ( mntopts[i] == "ro" )
return true;
}
return false; // Default is read-write mount
}
void Mount_Info::read_mountpoints_from_file_swaps( const Glib::ustring & filename, MountMapping & map )
{
std::string line;
std::string node;
std::ifstream file( filename.c_str() );
if ( file )
{
while ( getline( file, line ) )
{
node = Utils::regexp_label( line, "^(/[^ ]+)" );
if ( node.size() > 0 )
map[BlockSpecial( node )].mountpoints.push_back( "" /* no mountpoint for swap */ );
}
file.close();
}
}
// Return true only if the map contains a device name for the / (root) file system other
// than 'rootfs' and '/dev/root'.
bool Mount_Info::have_rootfs_dev( MountMapping & map )
{
MountMapping::const_iterator iter_mp;
for ( iter_mp = mount_info.begin() ; iter_mp != mount_info.end() ; iter_mp ++ )
{
if ( ! iter_mp->second.mountpoints.empty() && iter_mp->second.mountpoints[0] == "/" )
{
if ( iter_mp->first.m_name != "rootfs" && iter_mp->first.m_name != "/dev/root" )
return true;
}
}
return false;
}
void Mount_Info::read_mountpoints_from_mount_command( MountMapping & map )
{
Glib::ustring output;
Glib::ustring error;
if ( ! Utils::execute_command( "mount", output, error, true ) )
{
std::vector<Glib::ustring> lines;
Utils::split( output, lines, "\n");
for ( unsigned int i = 0 ; i < lines .size() ; i ++ )
{
// Process line like "/dev/sda3 on / type ext4 (rw)"
Glib::ustring node = Utils::regexp_label( lines[ i ], "^([^[:blank:]]+) on " );
Glib::ustring mountpoint = Utils::regexp_label( lines[ i ], "^[^[:blank:]]+ on ([^[:blank:]]+) " );
Glib::ustring mntopts = Utils::regexp_label( lines[i], " type [^[:blank:]]+ \\(([^\\)]*)\\)" );
if ( ! node.empty() )
add_mountpoint_entry( map, node, mountpoint, parse_readonly_flag( mntopts ) );
}
}
}
const MountEntry & Mount_Info::find( const MountMapping & map, const Glib::ustring & path )
{
MountMapping::const_iterator iter_mp = map.find( BlockSpecial( path ) );
if ( iter_mp != map.end() )
return iter_mp->second;
static MountEntry not_mounted = MountEntry();
return not_mounted;
}
} //GParted