Loop

Loop — plugin for operations with loop devices

Functions

gboolean bd_loop_init ()
void bd_loop_close ()
GQuark bd_loop_error_quark ()
BDLoopInfo * bd_loop_info ()
BDLoopInfo * bd_loop_info_copy ()
void bd_loop_info_free ()
gchar * bd_loop_get_loop_name ()
gboolean bd_loop_setup ()
gboolean bd_loop_setup_from_fd ()
gboolean bd_loop_teardown ()
gboolean bd_loop_set_autoclear ()
gboolean bd_loop_is_tech_avail ()

Types and Values

Includes

#include <loop.h>

Description

A plugin for operations with loop devices. All sizes passed in/out to/from the functions are in bytes.

Functions

bd_loop_init ()

gboolean
bd_loop_init (void);

Initializes the plugin. **This function is called automatically by the library's initialization functions.**


bd_loop_close ()

void
bd_loop_close (void);

Cleans up after the plugin. **This function is called automatically by the library's functions that unload it.**


bd_loop_error_quark ()

GQuark
bd_loop_error_quark (void);

[skip]


bd_loop_info ()

BDLoopInfo *
bd_loop_info (const gchar *loop,
              GError **error);

Parameters

loop

name of the loop device to get information about (e.g. "loop0")

 

error

place to store error (if any).

[out][optional]

Returns

information about the loop device or NULL in case of error

Tech category: BD_LOOP_TECH_LOOP-BD_LOOP_TECH_MODE_QUERY.

[transfer full]


bd_loop_info_copy ()

BDLoopInfo *
bd_loop_info_copy (BDLoopInfo *info);

Creates a new copy of info .

[skip]

Parameters

info

BDLoopInfo to copy.

[nullable]

bd_loop_info_free ()

void
bd_loop_info_free (BDLoopInfo *info);

Frees info .

[skip]

Parameters

info

BDLoopInfo to free.

[nullable]

bd_loop_get_loop_name ()

gchar *
bd_loop_get_loop_name (const gchar *file,
                       GError **error);

Parameters

file

path of the backing file to get loop name for

 

error

place to store error (if any).

[out][optional]

Returns

name of the loop device associated with the given file

Tech category: BD_LOOP_TECH_LOOP-BD_LOOP_TECH_MODE_QUERY.

[transfer full]


bd_loop_setup ()

gboolean
bd_loop_setup (const gchar *file,
               guint64 offset,
               guint64 size,
               gboolean read_only,
               gboolean part_scan,
               guint64 sector_size,
               const gchar **loop_name,
               GError **error);

Parameters

file

file to setup as a loop device

 

offset

offset of the start of the device (in file )

 

size

maximum size of the device (or 0 to leave unspecified)

 

read_only

whether to setup as read-only (TRUE) or read-write (FALSE)

 

part_scan

whether to enforce partition scan on the newly created device or not

 

sector_size

logical sector size for the loop device in bytes (or 0 for default)

 

loop_name

if not NULL, it is used to store the name of the loop device.

[optional][out]

error

place to store error (if any).

[out][optional]

Returns

whether the file was successfully setup as a loop device or not

Tech category: BD_LOOP_TECH_LOOP-BD_LOOP_TECH_MODE_CREATE


bd_loop_setup_from_fd ()

gboolean
bd_loop_setup_from_fd (gint fd,
                       guint64 offset,
                       guint64 size,
                       gboolean read_only,
                       gboolean part_scan,
                       guint64 sector_size,
                       const gchar **loop_name,
                       GError **error);

Parameters

fd

file descriptor for a file to setup as a new loop device

 

offset

offset of the start of the device (in file given by fd )

 

size

maximum size of the device (or 0 to leave unspecified)

 

read_only

whether to setup as read-only (TRUE) or read-write (FALSE)

 

part_scan

whether to enforce partition scan on the newly created device or not

 

sector_size

logical sector size for the loop device in bytes (or 0 for default)

 

loop_name

if not NULL, it is used to store the name of the loop device.

[optional][out]

error

place to store error (if any).

[out][optional]

Returns

whether an new loop device was successfully setup for fd or not

Tech category: BD_LOOP_TECH_LOOP-BD_LOOP_TECH_MODE_CREATE


bd_loop_teardown ()

gboolean
bd_loop_teardown (const gchar *loop,
                  GError **error);

Parameters

loop

path or name of the loop device to tear down

 

error

place to store error (if any).

[out][optional]

Returns

whether the loop device was successfully torn down or not

Tech category: BD_LOOP_TECH_LOOP-BD_LOOP_TECH_MODE_DESTROY


bd_loop_set_autoclear ()

gboolean
bd_loop_set_autoclear (const gchar *loop,
                       gboolean autoclear,
                       GError **error);

Parameters

loop

path or name of the loop device

 

autoclear

whether to set or unset the autoclear flag

 

error

place to store error (if any).

[out][optional]

Returns

whether the autoclear flag was successfully set on the loop device or not

Tech category: BD_LOOP_TECH_LOOP-BD_LOOP_TECH_MODE_MODIFY


bd_loop_is_tech_avail ()

gboolean
bd_loop_is_tech_avail (BDLoopTech tech,
                       guint64 mode,
                       GError **error);

Parameters

tech

the queried tech

 

mode

a bit mask of queried modes of operation (BDLoopTechMode) for tech

 

error

place to store error (details about why the tech -mode combination is not available).

[out][optional]

Returns

whether the tech -mode combination is available -- supported by the plugin implementation and having all the runtime dependencies available

Types and Values

BD_LOOP_ERROR

#define             BD_LOOP_ERROR

enum BDLoopError

Members

BD_LOOP_ERROR_TECH_UNAVAIL

   

BD_LOOP_ERROR_FAIL

   

BD_LOOP_ERROR_DEVICE

   

BDLoopInfo

typedef struct {
    gchar *backing_file;
    guint64 offset;
    gboolean autoclear;
    gboolean direct_io;
    gboolean part_scan;
    gboolean read_only;
} BDLoopInfo;

Members

gchar *backing_file;

backing file for the give loop device;

 

guint64 offset;

offset of the start of the device (in backing_file );

 

gboolean autoclear;

whether the autoclear flag is set or not;

 

gboolean direct_io;

whether direct IO is enabled or not;

 

gboolean part_scan;

whether the partition scan is enforced or not;

 

gboolean read_only;

whether the device is read-only or not;

 

enum BDLoopTech

Members

BD_LOOP_TECH_LOOP

   

enum BDLoopTechMode

Members

BD_LOOP_TECH_MODE_CREATE

   

BD_LOOP_TECH_MODE_DESTROY

   

BD_LOOP_TECH_MODE_MODIFY

   

BD_LOOP_TECH_MODE_QUERY