atoms.c File Reference

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Detailed Description

Atom management.

An atom is a single piece of information that is likely to be shared and which is therefore only allocated once: all other instances point to the common object.

Author:

Raphael Manfredi

Date:

2002-2003

#include <string.h>
#include "common.h"
#include "atoms.h"
#include "misc.h"
#include "glib-missing.h"
#include "walloc.h"
#include "override.h"

Data Structures
union	mem_chunk
struct	atom
	Atoms are ref-counted. More...
struct	table_desc
	Description of atom types. More...
Defines
#define	ATOMS_SOURCE
#define	ARENA_OFFSET   G_STRUCT_OFFSET(struct atom, arena)
#define	atom_protect(a)
#define	atom_unprotect(a)
#define	atom_alloc(size)   g_malloc(size)
#define	atom_dealloc(a)   g_free(a)
Typedefs
typedef atom	atom_t
	Atoms are ref-counted.
typedef gint(*	len_func_t )(gconstpointer v)
typedef const gchar *(*	str_func_t )(gconstpointer v)
typedef table_desc	table_desc_t
	Description of atom types.
Functions
	RCSID ("$Id:atoms.c, v 1.21 2005/12/27 16:29:29 cbiere Exp $")
gint	str_len (gconstpointer v)
const gchar *	str_str (gconstpointer v)
gint	guid_len (gconstpointer v)
const gchar *	guid_str (gconstpointer v)
gint	sha1_len (gconstpointer v)
const gchar *	sha1_str (gconstpointer v)
gint	uint64_len (gconstpointer v)
const gchar *	uint64_str (gconstpointer v)
guint	binary_hash (const guchar *key, guint len)
	Hash `len' bytes (multiple of 4) starting from `key'.
guint	guid_hash (gconstpointer key)
	Hash a GUID (16 bytes).
gint	guid_eq (gconstpointer a, gconstpointer b)
	Test two GUIDs for equality.
guint	sha1_hash (gconstpointer key)
	Hash a SHA1 (20 bytes).
gint	sha1_eq (gconstpointer a, gconstpointer b)
	Test two SHA1s for equality.
gint	uint64_eq (gconstpointer a, gconstpointer b)
	Test two 64-bit integers for equality.
guint	uint64_hash (gconstpointer p)
	Calculate the 32-bit hash of a 64-bit integer.
void	atoms_init (void)
	Initialize atom structures.
gpointer	atom_get (gint type, gconstpointer key)
	Get atom of given `type', whose value is `key'.
void	atom_free (gint type, gconstpointer key)
	Remove one reference from atom.
gboolean	atom_warn_free (gpointer key, gpointer unused_value, gpointer udata)
	Warning about existing atom that should have been freed.
void	atoms_close (void)
	Shutdown atom structures, freeing all remaining atoms.
Variables
table_desc_t	atoms []
	The set of all atom types we know about.

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Define Documentation

#define ARENA_OFFSET   G_STRUCT_OFFSET(struct atom, arena)

#define atom_alloc (  size   )     g_malloc(size)

#define atom_dealloc (  a   )     g_free(a)

#define atom_protect (  a   )

#define atom_unprotect (  a   )

#define ATOMS_SOURCE

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Typedef Documentation

typedef struct atom atom_t

Atoms are ref-counted. The reference count is held at the beginning of the data arena. What we return to the outside is a pointer to arena[], not to the atom structure.

typedef gint(* len_func_t)(gconstpointer v)

typedef const gchar*(* str_func_t)(gconstpointer v)

typedef struct table_desc table_desc_t

Description of atom types.

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Function Documentation

void atom_free (  gint  type, gconstpointer  key )

Remove one reference from atom. Dispose of atom if nobody references it anymore.

gpointer atom_get (  gint  type, gconstpointer  key )

Get atom of given `type', whose value is `key'. If the atom does not exist yet, `key' is cloned and makes up the new atom. Returns: the atom's value.

gboolean atom_warn_free (  gpointer  key, gpointer  unused_value, gpointer  udata )  [static]

Warning about existing atom that should have been freed.

void atoms_close (  void   )

Shutdown atom structures, freeing all remaining atoms.

void atoms_init (  void   )

Initialize atom structures.

guint binary_hash (  const guchar *  key, guint  len )

Hash `len' bytes (multiple of 4) starting from `key'.

gint guid_eq (  gconstpointer  a, gconstpointer  b )

Test two GUIDs for equality.

guint guid_hash (  gconstpointer  key  )

Hash a GUID (16 bytes).

gint guid_len (  gconstpointer  unused_guid  )  [static]

Returns: length of GUID.

const gchar * guid_str (  gconstpointer  v  )  [static]

Returns: printable form of a GUID, as pointer to static data.

RCSID (  "$Id:atoms.  c, v 1.21 2005/12/27 16:29:29 cbiere Exp $"  )

gint sha1_eq (  gconstpointer  a, gconstpointer  b )

Test two SHA1s for equality. Attention: NB: This routine is visible for the download mesh.

guint sha1_hash (  gconstpointer  key  )

Hash a SHA1 (20 bytes). Attention: NB: This routine is visible for the download mesh.

gint sha1_len (  gconstpointer  unused_sha1  )  [static]

Returns: length of SHA1.

const gchar * sha1_str (  gconstpointer  sha1  )  [static]

Returns: printable form of a SHA1, as pointer to static data.

gint str_len (  gconstpointer  v  )  [static]

Returns: length of string + trailing NUL.

const gchar * str_str (  gconstpointer  v  )  [static]

Returns: printable form of a string, i.e. self.

gint uint64_eq (  gconstpointer  a, gconstpointer  b )

Test two 64-bit integers for equality. Returns: whether both referenced 64-bit integers are equal.

guint uint64_hash (  gconstpointer  key  )

Calculate the 32-bit hash of a 64-bit integer. Returns: the 32-bit hash value for the referenced 64-bit integer.

int uint64_len (  gconstpointer  unused_v  )  [static]

Returns: length of an int.

const gchar * uint64_str (  gconstpointer  v  )  [static]

Returns: printable form of an int, as pointer to static data.

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Variable Documentation

table_desc_t atoms[] [static]

Initial value: { { "String", NULL, g_str_hash, g_str_equal, str_len, str_str }, { "GUID", NULL, guid_hash, guid_eq, guid_len, guid_str }, { "SHA1", NULL, sha1_hash, sha1_eq, sha1_len, sha1_str }, { "uint64", NULL, uint64_hash, uint64_eq, uint64_len, uint64_str}, } The set of all atom types we know about.

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