blockdev library: libblockdev Reference Manual

## blockdev library

blockdev library — a library for doing low-level operations with block devices

## Functions

gboolean | bd_init ()
gboolean | bd_ensure_init ()
gboolean | bd_try_init ()
gboolean | bd_reinit ()
gboolean | bd_try_reinit ()
gboolean | bd_is_initialized ()
gboolean | bd_switch_init_checks ()
GQuark | bd_init_error_quark ()

## Types and Values

#define | BD_INIT_ERROR
enum | BDInitError

## Includes

    #include <blockdev.h>

## Description

## Functions

### bd_init ()

    gboolean
    bd_init (BDPluginSpec **require_plugins,
             BDUtilsLogFunc log_func,
             GError **error);

#### Parameters

require_plugins | `NULL`-terminated list of plugins that should be loaded (if no so_name is specified for the plugin, the default is used) or `NULL` to load all plugins. | [allow-none][array zero-terminated=1]
log_func | logging function to use. | [allow-none][scope notified]
error | place to store error (if any). | [out]

#### Returns

whether the library was successfully initialized with all the required or default (see `require_plugins` ) plugins or not

Example of libblockdev initialization with 'fs' and 'lvm' plugins. Specific version of the lvm plugin is required:

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    GError *error = NULL;
    gboolean ret = FALSE;
    BDPluginSpec fs_plugin = {BD_PLUGIN_FS, NULL};
    BDPluginSpec lvm_plugin = {BD_PLUGIN_LVM, "libbd_lvm.so.2"};
    BDPluginSpec *plugins[] = {&fs_plugin, &lvm_plugin, NULL};
    ret = bd_init (plugins, NULL, &error);

### bd_ensure_init ()

    gboolean
    bd_ensure_init (BDPluginSpec **require_plugins,
                    BDUtilsLogFunc log_func,
                    GError **error);

Checks the state of the library and if it is uninitialized or not all the `require_plugins` plugins are available, tries to (re)initialize it. Otherwise just returns early. The difference between:

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    if (!bd_is_initialized())
        bd_init(None, None, &error);

and this function is that this function does the check and init in an atomic way (holding the lock preventing other threads from doing changes in between).

#### Parameters

require_plugins | `NULL`-terminated list of plugins that should be loaded (if no so_name is specified for the plugin, the default is used) or `NULL` to load all plugins. | [allow-none][array zero-terminated=1]
log_func | logging function to use. | [allow-none][scope notified]
error | place to store error (if any). | [out]

#### Returns

whether the library was successfully initialized with all the required or default (see `require_plugins` ) plugins or not either before or by this call

### bd_try_init ()

    gboolean
    bd_try_init (BDPluginSpec **request_plugins,
                 BDUtilsLogFunc log_func,
                 gchar ***loaded_plugin_names,
                 GError **error);

#### Parameters

request_plugins | `NULL`-terminated list of plugins that should be loaded (if no so_name is specified for the plugin, the default is used) or `NULL` to load all plugins. | [allow-none][array zero-terminated=1]
log_func | logging function to use. | [allow-none][scope notified]
loaded_plugin_names | names of the successfully loaded plugins. | [allow-none][out][transfer container][array zero-terminated=1]
error | place to store error (if any). | [out]

#### Returns

whether the library was successfully initialized with all the required or default (see `require_plugins` ) plugins or not

*UNLIKE IN CASE OF `bd_init()` AND `bd_ensure_init()`, FAILURE TO LOAD A PLUGIN IS NOT CONSIDERED ERROR*

### bd_reinit ()

    gboolean
    bd_reinit (BDPluginSpec **require_plugins,
               gboolean reload,
               BDUtilsLogFunc log_func,
               GError **error);

#### Parameters

require_plugins | `NULL`-terminated list of plugins that should be loaded (if no so_name is specified for the plugin, the default is used) or `NULL` to load all plugins. | [allow-none][array zero-terminated=1]
reload | whether to reload the already loaded plugins or not |
log_func | logging function to use or `NULL` to keep the old one. | [allow-none][scope notified]
error | place to store error (if any). | [out]

#### Returns

whether the library was successfully initialized or not

If `reload` is `TRUE` all the plugins are closed and reloaded otherwise only the missing plugins are loaded.

### bd_try_reinit ()

    gboolean
    bd_try_reinit (BDPluginSpec **require_plugins,
                   gboolean reload,
                   BDUtilsLogFunc log_func,
                   gchar ***loaded_plugin_names,
                   GError **error);

#### Parameters

require_plugins | `NULL`-terminated list of plugins that should be loaded (if no so_name is specified for the plugin, the default is used) or `NULL` to load all plugins. | [allow-none][array zero-terminated=1]
reload | whether to reload the already loaded plugins or not |
log_func | logging function to use or `NULL` to keep the old one. | [allow-none][scope notified]
loaded_plugin_names | names of the successfully loaded plugins. | [allow-none][out][transfer container][array zero-terminated=1]
error | place to store error (if any). | [out]

#### Returns

whether the library was successfully initialized or not

If `reload` is `TRUE` all the plugins are closed and reloaded otherwise only the missing plugins are loaded.

*UNLIKE IN CASE OF `bd_init()` AND `bd_ensure_init()`, FAILURE TO LOAD A PLUGIN IS NOT CONSIDERED ERROR*

### bd_is_initialized ()

    gboolean
    bd_is_initialized (void);

#### Returns

whether the library is initialized or not

The library is considered initialized if some of the *init*() functions was/were called and either at least one plugin is loaded or 0 plugins are loaded after an explicit call that requested 0 plugins to be loaded.

### bd_switch_init_checks ()

    gboolean
    bd_switch_init_checks (gboolean enable,
                           GError **error);

Enables or disables plugins' init checks based on `enable` .

Note: The current implementation (un)sets the LIBBLOCKDEV_SKIP_DEP_CHECKS environment variable.

#### Parameters

enable | whether to enable init checks (`TRUE`) or not (`FALSE`) |
error | place to store error (if any). | [out]

### bd_init_error_quark ()

    GQuark
    bd_init_error_quark (void);

[skip]

## Types and Values

### BD_INIT_ERROR

    #define BD_INIT_ERROR bd_init_error_quark ()

### enum BDInitError

#### Members

BD_INIT_ERROR_PLUGINS_FAILED |  |
BD_INIT_ERROR_NOT_IMPLEMENTED |  |
BD_INIT_ERROR_FAILED |  |