Camel Reference Manual: CamelKeyFile

## CamelKeyFile CamelKeyFile |

## Functions

#define | CAMEL_BLOCK_SIZE
#define | CAMEL_BLOCK_SIZE_BITS
CamelBlockFile * | camel_block_file_new ()
gint | camel_block_file_rename ()
gint | camel_block_file_delete ()
CamelBlock * | camel_block_file_new_block ()
gint | camel_block_file_free_block ()
CamelBlock * | camel_block_file_get_block ()
void | camel_block_file_detach_block ()
void | camel_block_file_attach_block ()
void | camel_block_file_touch_block ()
void | camel_block_file_unref_block ()
gint | camel_block_file_sync_block ()
gint | camel_block_file_sync ()
CamelKeyFile * | camel_key_file_new ()
gint | camel_key_file_rename ()
gint | camel_key_file_delete ()
gint | camel_key_file_write ()
gint | camel_key_file_read ()

## Types and Values

typedef | camel_block_t
typedef | camel_key_t
enum | CamelBlockFileFlags
enum | CamelBlockFlags
struct | CamelBlockRoot
struct | CamelBlock
struct | CamelBlockFile
struct | CamelKeyFile

## Object Hierarchy

        GObject
        ├── CamelBlockFile
        ╰── CamelKeyFile

## Description

## Functions

### CAMEL_BLOCK_SIZE

    #define CAMEL_BLOCK_SIZE (1024)

### CAMEL_BLOCK_SIZE_BITS

    #define CAMEL_BLOCK_SIZE_BITS (10) /* # bits to contain block_size bytes */

### camel_block_file_new ()

    CamelBlockFile *
    camel_block_file_new (const gchar *path,
                          gint flags,
                          const gchar version[8],
                          gsize block_size);

Allocate a new block file, stored at `path` . `version` contains an 8 character version string which must match the head of the file, or the file will be intitialised.

`block_size` is currently ignored and is set to CAMEL_BLOCK_SIZE.

#### Parameters

path | @: |

#### Returns

The new block file, or NULL if it could not be created.

### camel_block_file_rename ()

    gint
    camel_block_file_rename (CamelBlockFile *bs,
                             const gchar *path);

### camel_block_file_delete ()

    gint
    camel_block_file_delete (CamelBlockFile *kf);

### camel_block_file_new_block ()

    CamelBlock *
    camel_block_file_new_block (CamelBlockFile *bs);

Allocate a new block, return a pointer to it. Old blocks may be flushed to disk during this call.

#### Returns

The block, or NULL if an error occurred.

### camel_block_file_free_block ()

    gint
    camel_block_file_free_block (CamelBlockFile *bs,
                                 camel_block_t id);

### camel_block_file_get_block ()

    CamelBlock *
    camel_block_file_get_block (CamelBlockFile *bs,
                                camel_block_t id);

Retreive a block `id` .

#### Returns

The block, or NULL if blockid is invalid or a file error occurred.

### camel_block_file_detach_block ()

    void
    camel_block_file_detach_block (CamelBlockFile *bs,
                                   CamelBlock *bl);

Detatch a block from the block file's cache. The block should be unref'd or attached when finished with. The block file will perform no writes of this block or flushing of it if the cache fills.

### camel_block_file_attach_block ()

    void
    camel_block_file_attach_block (CamelBlockFile *bs,
                                   CamelBlock *bl);

Reattach a block that has been detached.

### camel_block_file_touch_block ()

    void
    camel_block_file_touch_block (CamelBlockFile *bs,
                                  CamelBlock *bl);

Mark a block as dirty. The block will be written to disk if it ever expires from the cache.

### camel_block_file_unref_block ()

    void
    camel_block_file_unref_block (CamelBlockFile *bs,
                                  CamelBlock *bl);

Mark a block as unused. If a block is used it will not be written to disk, or flushed from memory.

If a block is detatched and this is the last reference, the block will be freed.

### camel_block_file_sync_block ()

    gint
    camel_block_file_sync_block (CamelBlockFile *bs,
                                 CamelBlock *bl);

Flush a block to disk immediately. The block will only be flushed to disk if it is marked as dirty (touched).

#### Returns

-1 on io error.

### camel_block_file_sync ()

    gint
    camel_block_file_sync (CamelBlockFile *bs);

Sync all dirty blocks to disk, including the root block.

#### Returns

-1 on io error.

### camel_key_file_new ()

    CamelKeyFile *
    camel_key_file_new (const gchar *path,
                        gint flags,
                        const gchar version[8]);

Create a new key file. A linked list of record blocks.

#### Parameters

flags | open flags |
version | Version string (header) of file. Currently written but not checked. |

#### Returns

A new key file, or NULL if the file could not be opened/created/initialised.

### camel_key_file_rename ()

    gint
    camel_key_file_rename (CamelKeyFile *kf,
                           const gchar *path);

### camel_key_file_delete ()

    gint
    camel_key_file_delete (CamelKeyFile *kf);

### camel_key_file_write ()

    gint
    camel_key_file_write (CamelKeyFile *kf,
                          camel_block_t *parent,
                          gsize len,
                          camel_key_t *records);

Write a new list of records to the key file.

#### Returns

-1 on io error. The key file will remain unchanged.

### camel_key_file_read ()

    gint
    camel_key_file_read (CamelKeyFile *kf,
                         camel_block_t *start,
                         gsize *len,
                         camel_key_t **records);

Read the next block of data from the key file. Returns the number of records.

#### Parameters

start | The record pointer. This will be set to the next record pointer on success. |
len | Number of records read, if != NULL. |
records | Records, allocated, must be freed with g_free, if != NULL. |

#### Returns

-1 on io error.

## Types and Values

### camel_block_t

    typedef guint32 camel_block_t; /* block offset, absolute, bottom BLOCK_SIZE_BITS always 0 */

### camel_key_t

    typedef guint32 camel_key_t; /* this is a bitfield of (block offset:BLOCK_SIZE_BITS) */

### enum CamelBlockFileFlags

#### Members

CAMEL_BLOCK_FILE_SYNC |  |

### enum CamelBlockFlags

#### Members

CAMEL_BLOCK_DIRTY |  |
CAMEL_BLOCK_DETACHED |  |

### struct CamelBlockRoot

    struct CamelBlockRoot {
    	gchar version[8]; /* version number */

    	guint32 flags;		/* flags for file */
    	guint32 block_size; /* block size of this file */
    	camel_block_t free; /* free block list */
    	camel_block_t last; /* pointer to end of blocks */

    	/* subclasses tack on, but no more than CAMEL_BLOCK_SIZE! */
    };

### struct CamelBlock

    struct CamelBlock {
    	camel_block_t id;
    	CamelBlockFlags flags;
    	guint32 refcount;
    	guint32 align00;

    	guchar data[CAMEL_BLOCK_SIZE];
    };

### struct CamelBlockFile

    struct CamelBlockFile;

### struct CamelKeyFile

    struct CamelKeyFile;