[gparted] Enable to work with new dmraid and parted without dmraid support

[Curtis Gedak <gedakc src gnome org>]

commit cf68fc07040e7c18f2dccce48e6d20bd71d9faa1
Author: Curtis Gedak <gedakc gmail com>
Date:   Wed Aug 25 10:33:02 2010 -0600

    Enable to work with new dmraid and parted without dmraid support
    
    Newer versions (dmraid-1.0.0-rc16?) of dmraid default to always
    creating partition names by inserting the letter 'p' between the
    device name and the partition number.  Since this is not
    consistent with older versions of dmraid, add extra logic to
    ensure that newer versions of dmraid do not insert this extra
    letter 'p'.
    
    Rename method get_udev_name to get_udev_dm_name and enhance to
    retrieve the property DM_NAME.
    
    Handle situation where parted, and hence libparted, has been
    configured with --disable-device-mapper.  In this situation on
    some distros the device name could be /dev/dm-0.  This results in
    invalid partition names such as /dev/dm-0p1.  Add logic to decode
    the actual /dev/mapper name.

 include/DMRaid.h |    2 +-
 src/DMRaid.cc    |   85 ++++++++++++++++++++++++++++++++++++++---------------
 2 files changed, 62 insertions(+), 25 deletions(-)
---
diff --git a/include/DMRaid.h b/include/DMRaid.h
index ac7cfc9..6ddf734 100644
--- a/include/DMRaid.h
+++ b/include/DMRaid.h
@@ -52,7 +52,7 @@ public:
 	void get_devices( std::vector<Glib::ustring> & dmraid_devices ) ;
 	Glib::ustring get_dmraid_name( const Glib::ustring & dev_path ) ;
 	int get_partition_number( const Glib::ustring & partition_name ) ;
-	Glib::ustring get_udev_name( const Glib::ustring & dev_path ) ;
+	Glib::ustring get_udev_dm_name( const Glib::ustring & dev_path ) ;
 	Glib::ustring make_path_dmraid_compatible( Glib::ustring partition_path ) ;
 	bool create_dev_map_entries( const Partition & partition, OperationDetail & operationdetail ) ;
 	bool create_dev_map_entries( const Glib::ustring & dev_path ) ;
diff --git a/src/DMRaid.cc b/src/DMRaid.cc
index e954a8d..79da86c 100644
--- a/src/DMRaid.cc
+++ b/src/DMRaid.cc
@@ -110,11 +110,19 @@ bool DMRaid::is_dmraid_device( const Glib::ustring & dev_path )
 	//  also check with udev to see if they are in fact dmraid devices
 	if ( ! device_found && ( dev_path .find( "/dev/dm" ) != Glib::ustring::npos ) )
 	{
-		Glib::ustring udev_name = get_udev_name( dev_path ) ;
+		//Ensure we use the base device name if dev_path in form /dev/dm-#p#
+		Glib::ustring regexp = "(/dev/dm-[0-9]+)p[0-9]+" ;
+		Glib::ustring dev_path_only = Utils::regexp_label( dev_path, regexp ) ;
+		if ( dev_path_only .empty() )
+			dev_path_only = dev_path ;
+
+		Glib::ustring udev_name = get_udev_dm_name( dev_path_only ) ;
 		if ( ! udev_name .empty() )
+		{
 			for ( unsigned int k=0; k < dmraid_devices .size(); k++ )
 				if ( udev_name .find( dmraid_devices[k] ) != Glib::ustring::npos )
 					device_found = true ;
+		}
 
 		//Also check for a symbolic link if device not yet found
 		if ( ! device_found && file_test( dev_path, Glib::FILE_TEST_IS_SYMLINK ) )
@@ -179,7 +187,7 @@ Glib::ustring DMRaid::get_dmraid_name( const Glib::ustring & dev_path )
 	//  also check with udev for dmraid name
 	if ( dmraid_name .empty() && ( dev_path .find( "/dev/dm" ) != Glib::ustring::npos ) )
 	{
-		Glib::ustring udev_name = get_udev_name( dev_path ) ;
+		Glib::ustring udev_name = get_udev_dm_name( dev_path ) ;
 		for ( unsigned int k=0; k < dmraid_devices .size(); k++ )
 			if ( udev_name .find( dmraid_devices[k] ) != Glib::ustring::npos )
 				dmraid_name = dmraid_devices[k] ;
@@ -227,31 +235,25 @@ int DMRaid::get_partition_number( const Glib::ustring & partition_name )
 	return std::atoi( Utils::regexp_label( partition_name, dmraid_name + "p?([0-9]+)" ) .c_str() ) ;
 }
 
-Glib::ustring DMRaid::get_udev_name( const Glib::ustring & dev_path )
+Glib::ustring DMRaid::get_udev_dm_name( const Glib::ustring & dev_path )
 {
-	//Retrieve name of device using udev information
+	//Retrieve DM_NAME of device using udev information
 	Glib::ustring output = "" ;
 	Glib::ustring error  = "" ;
-	Glib::ustring udev_name = "" ;
+	Glib::ustring dm_name = "" ;
 
 	if ( udevinfo_found )
-	{
-		if ( ! Utils::execute_command( "udevinfo --query=name --name=" + dev_path, output, error, true ) )
-			udev_name = output ;
-	}
+		Utils::execute_command( "udevinfo --query=all --name=" + dev_path, output, error, true ) ;
 	else if ( udevadm_found )
-	{
-		if ( ! Utils::execute_command( "udevadm info --query=name --name=" + dev_path, output, error, true ) )
-			udev_name = output ;
-	}
+		Utils::execute_command( "udevadm info --query=all --name=" + dev_path, output, error, true ) ;
 
-	if ( ! udev_name .empty() )
+	if ( ! output .empty() )
 	{
-		//Extract portion of name after last '/'
-		udev_name = Utils::regexp_label( udev_name, "([^/]*)$" ) ;
+		Glib::ustring regexp = "^E: DM_NAME=([^\n]*)$" ;
+		dm_name = Utils::regexp_label( output, regexp ) ;
 	}
 
-	return udev_name ;
+	return dm_name ;
 }
 
 Glib::ustring DMRaid::make_path_dmraid_compatible( Glib::ustring partition_path )
@@ -278,14 +280,33 @@ Glib::ustring DMRaid::make_path_dmraid_compatible( Glib::ustring partition_path
 	//  Instead in all cases dmraid simply appends the partition number to the
 	//  device name to create a partition name.
 	//
+	Glib::ustring reg_exp ;
+	Glib::ustring partition_number ;
+
 	for ( unsigned int k=0; k < dmraid_devices .size(); k++ )
 	{
-		Glib::ustring reg_exp = DEV_MAP_PATH + dmraid_devices[ k ] + "p([0-9]+)" ;
-		Glib::ustring partition_number = Utils::regexp_label( partition_path, reg_exp ) ;
+		reg_exp = DEV_MAP_PATH + dmraid_devices[ k ] + "p([0-9]+)" ;
+		partition_number = Utils::regexp_label( partition_path, reg_exp ) ;
 		if ( ! partition_number .empty() )
 		{
 			partition_path = DEV_MAP_PATH + dmraid_devices[ k ] + partition_number ;
-			break ;
+			return partition_path ;
+		}
+	}
+
+	//If parted is configured with --disable-device-mapper then the partition path
+	//  could default to something like /dev/dm-#p# on some distros, so we need to
+	//  convert these names back into /dev/mapper entries
+	reg_exp = "/dev/dm-[0-9]+p([0-9]+)" ;
+	partition_number = Utils::regexp_label( partition_path, reg_exp ) ;
+	if ( ! partition_number .empty() )
+	{
+		reg_exp = "(/dev/dm-[0-9]+)p[0-9]+" ;
+		Glib::ustring device_path = Utils::regexp_label( partition_path, reg_exp ) ;
+		if ( ! device_path .empty() )
+		{
+			device_path = get_udev_dm_name( device_path ) ;
+			partition_path = DEV_MAP_PATH + device_path + partition_number ;
 		}
 	}
 
@@ -304,9 +325,17 @@ bool DMRaid::create_dev_map_entries( const Partition & partition, OperationDetai
 	Glib::ustring tmp = String::ucompose ( _("create missing %1 entries"), DEV_MAP_PATH ) ;
 	operationdetail .add_child( OperationDetail( tmp ) );
 
-	command = "dmraid -ay -v" ;
+	//Newer dmraid defaults to always inserting the letter 'p' between the device name
+	//  and the partition number.  Since the '-P' option is not valid for older dmraid
+	//  versions, try with and without the '-P' option.
+	command = "dmraid -ay -P \"\" -v" ;
 	if ( execute_command( command, operationdetail .get_last_child() ) )
-		exit_status = false ;	//command failed
+	{
+		//Above command failed, so try without the '-P' option.
+		command = "dmraid -ay -v" ;
+		if ( execute_command( command, operationdetail .get_last_child() ) )
+			exit_status = false ;	//command failed
+	}
 
 	if ( kpartx_found )
 	{
@@ -329,9 +358,17 @@ bool DMRaid::create_dev_map_entries( const Glib::ustring & dev_path )
 	Glib::ustring command, output, error ;
 	bool exit_status = true ;
 
-	command = "dmraid -ay -v" ;
+	//Newer dmraid defaults to always inserting the letter 'p' between the device name
+	//  and the partition number.  Since the '-P' option is not valid for older dmraid
+	//  versions, try with and without the '-P' option.
+	command = "dmraid -ay -P \"\" -v" ;
 	if ( Utils::execute_command( command, output, error, true ) )
-		exit_status = false;	//command failed
+	{
+		//Above command failed, so try without the '-P' option.
+		command = "dmraid -ay -v" ;
+		if ( Utils::execute_command( command, output, error, true ) )
+			exit_status = false;	//command failed
+	}
 
 	if ( kpartx_found )
 	{