[p5sagit/p5-mst-13.2.git] / hv.h

/*    hv.h
 *
 *    Copyright (C) 1991, 1992, 1993, 1996, 1997, 1998, 1999,
 *    2000, 2001, 2002, 2005, by Larry Wall and others
 *
 *    You may distribute under the terms of either the GNU General Public
 *    License or the Artistic License, as specified in the README file.
 *
 */

/* typedefs to eliminate some typing */
typedef struct he HE;
typedef struct hek HEK;

/* entry in hash value chain */
struct he {
    HE		*hent_next;	/* next entry in chain */
    HEK		*hent_hek;	/* hash key */
    SV		*hent_val;	/* scalar value that was hashed */
};

/* hash key -- defined separately for use as shared pointer */
struct hek {
    U32		hek_hash;	/* hash of key */
    I32		hek_len;	/* length of hash key */
    char	hek_key[1];	/* variable-length hash key */
    /* the hash-key is \0-terminated */
    /* after the \0 there is a byte for flags, such as whether the key
       is UTF-8 */
};


/* Subject to change.
   Don't access this directly.
*/
struct xpvhv_aux {
    char	*xhv_name;	/* name, if a symbol table */
    HE		*xhv_eiter;	/* current entry of iterator */
    I32		xhv_riter;	/* current root of iterator */
};

/* hash structure: */
/* This structure must match the beginning of struct xpvmg in sv.h. */
struct xpvhv {
    char *	xhv_array;	/* pointer to malloced string */
    STRLEN	xhv_fill;	/* how full xhv_array currently is */
    STRLEN	xhv_max;	/* subscript of last element of xhv_array */
    IV		xhv_keys;	/* how many elements in the array */
    NV		xnv_nv;		/* numeric value, if any */
    MAGIC*	xmg_magic;	/* magic for scalar array */
    HV*		xmg_stash;	/* class package */

    struct xpvhv_aux* xhv_aux;
    /* list of pm's for this package is now stored in symtab magic.  */
};

/* hash a key */
/* FYI: This is the "One-at-a-Time" algorithm by Bob Jenkins
 * from requirements by Colin Plumb.
 * (http://burtleburtle.net/bob/hash/doobs.html) */
/* The use of a temporary pointer and the casting games
 * is needed to serve the dual purposes of
 * (a) the hashed data being interpreted as "unsigned char" (new since 5.8,
 *     a "char" can be either signed or signed, depending on the compiler)
 * (b) catering for old code that uses a "char"
 *
 * The "hash seed" feature was added in Perl 5.8.1 to perturb the results
 * to avoid "algorithmic complexity attacks".
 *
 * If USE_HASH_SEED is defined, hash randomisation is done by default
 * If USE_HASH_SEED_EXPLICIT is defined, hash randomisation is done
 * only if the environment variable PERL_HASH_SEED is set.
 * For maximal control, one can define PERL_HASH_SEED.
 * (see also perl.c:perl_parse()).
 */
#ifndef PERL_HASH_SEED
#   if defined(USE_HASH_SEED) || defined(USE_HASH_SEED_EXPLICIT)
#       define PERL_HASH_SEED	PL_hash_seed
#   else
#       define PERL_HASH_SEED	0
#   endif
#endif
#define PERL_HASH(hash,str,len) \
     STMT_START	{ \
	register const char *s_PeRlHaSh_tmp = str; \
	register const unsigned char *s_PeRlHaSh = (const unsigned char *)s_PeRlHaSh_tmp; \
	register I32 i_PeRlHaSh = len; \
	register U32 hash_PeRlHaSh = PERL_HASH_SEED; \
	while (i_PeRlHaSh--) { \
	    hash_PeRlHaSh += *s_PeRlHaSh++; \
	    hash_PeRlHaSh += (hash_PeRlHaSh << 10); \
	    hash_PeRlHaSh ^= (hash_PeRlHaSh >> 6); \
	} \
	hash_PeRlHaSh += (hash_PeRlHaSh << 3); \
	hash_PeRlHaSh ^= (hash_PeRlHaSh >> 11); \
	(hash) = (hash_PeRlHaSh + (hash_PeRlHaSh << 15)); \
    } STMT_END

/* Only hv.c and mod_perl should be doing this.  */
#ifdef PERL_HASH_INTERNAL_ACCESS
#define PERL_HASH_INTERNAL(hash,str,len) \
     STMT_START	{ \
	register const char *s_PeRlHaSh_tmp = str; \
	register const unsigned char *s_PeRlHaSh = (const unsigned char *)s_PeRlHaSh_tmp; \
	register I32 i_PeRlHaSh = len; \
	register U32 hash_PeRlHaSh = PL_rehash_seed; \
	while (i_PeRlHaSh--) { \
	    hash_PeRlHaSh += *s_PeRlHaSh++; \
	    hash_PeRlHaSh += (hash_PeRlHaSh << 10); \
	    hash_PeRlHaSh ^= (hash_PeRlHaSh >> 6); \
	} \
	hash_PeRlHaSh += (hash_PeRlHaSh << 3); \
	hash_PeRlHaSh ^= (hash_PeRlHaSh >> 11); \
	(hash) = (hash_PeRlHaSh + (hash_PeRlHaSh << 15)); \
    } STMT_END
#endif

/*
=head1 Hash Manipulation Functions

=for apidoc AmU||HEf_SVKEY
This flag, used in the length slot of hash entries and magic structures,
specifies the structure contains an C<SV*> pointer where a C<char*> pointer
is to be expected. (For information only--not to be used).

=head1 Handy Values

=for apidoc AmU||Nullhv
Null HV pointer.

=head1 Hash Manipulation Functions

=for apidoc Am|char*|HvNAME|HV* stash
Returns the package name of a stash.  See C<SvSTASH>, C<CvSTASH>.

=for apidoc Am|void*|HeKEY|HE* he
Returns the actual pointer stored in the key slot of the hash entry. The
pointer may be either C<char*> or C<SV*>, depending on the value of
C<HeKLEN()>.  Can be assigned to.  The C<HePV()> or C<HeSVKEY()> macros are
usually preferable for finding the value of a key.

=for apidoc Am|STRLEN|HeKLEN|HE* he
If this is negative, and amounts to C<HEf_SVKEY>, it indicates the entry
holds an C<SV*> key.  Otherwise, holds the actual length of the key.  Can
be assigned to. The C<HePV()> macro is usually preferable for finding key
lengths.

=for apidoc Am|SV*|HeVAL|HE* he
Returns the value slot (type C<SV*>) stored in the hash entry.

=for apidoc Am|U32|HeHASH|HE* he
Returns the computed hash stored in the hash entry.

=for apidoc Am|char*|HePV|HE* he|STRLEN len
Returns the key slot of the hash entry as a C<char*> value, doing any
necessary dereferencing of possibly C<SV*> keys.  The length of the string
is placed in C<len> (this is a macro, so do I<not> use C<&len>).  If you do
not care about what the length of the key is, you may use the global
variable C<PL_na>, though this is rather less efficient than using a local
variable.  Remember though, that hash keys in perl are free to contain
embedded nulls, so using C<strlen()> or similar is not a good way to find
the length of hash keys. This is very similar to the C<SvPV()> macro
described elsewhere in this document.

=for apidoc Am|SV*|HeSVKEY|HE* he
Returns the key as an C<SV*>, or C<Nullsv> if the hash entry does not
contain an C<SV*> key.

=for apidoc Am|SV*|HeSVKEY_force|HE* he
Returns the key as an C<SV*>.  Will create and return a temporary mortal
C<SV*> if the hash entry contains only a C<char*> key.

=for apidoc Am|SV*|HeSVKEY_set|HE* he|SV* sv
Sets the key to a given C<SV*>, taking care to set the appropriate flags to
indicate the presence of an C<SV*> key, and returns the same
C<SV*>.

=cut
*/

/* these hash entry flags ride on hent_klen (for use only in magic/tied HVs) */
#define HEf_SVKEY	-2	/* hent_key is an SV* */


#define Nullhv Null(HV*)
#define HvARRAY(hv)	(*(HE***)&((XPVHV*)  SvANY(hv))->xhv_array)
#define HvFILL(hv)	((XPVHV*)  SvANY(hv))->xhv_fill
#define HvMAX(hv)	((XPVHV*)  SvANY(hv))->xhv_max
#define HvRITER(hv)	(*Perl_hv_riter_p(aTHX_ (HV*)(hv)))
#define HvEITER(hv)	(*Perl_hv_eiter_p(aTHX_ (HV*)(hv)))
#define HvRITER_set(hv,r)	Perl_hv_riter_set(aTHX_ (HV*)(hv), r)
#define HvEITER_set(hv,e)	Perl_hv_eiter_set(aTHX_ (HV*)(hv), e)
#define HvRITER_get(hv)	(((XPVHV *)SvANY(hv))->xhv_aux ? \
			 ((struct xpvhv_aux*)((XPVHV *)SvANY(hv))->xhv_aux)->xhv_riter : -1)
#define HvEITER_get(hv)	(((XPVHV *)SvANY(hv))->xhv_aux ? \
			 ((struct xpvhv_aux *)((XPVHV *)SvANY(hv))->xhv_aux)->xhv_eiter : 0)
#define HvNAME(hv)	(*Perl_hv_name_p(aTHX_ (HV*)hv))
/* FIXME - all of these should use a UTF8 aware API, which should also involve
   getting the length. */
#define HvNAME_get(hv)	(((XPVHV *)SvANY(hv))->xhv_aux ? \
			 ((struct xpvhv_aux *)((XPVHV *)SvANY(hv))->xhv_aux)->xhv_name : 0)

/* the number of keys (including any placeholers) */
#define XHvTOTALKEYS(xhv)	((xhv)->xhv_keys)

/*
 * HvKEYS gets the number of keys that actually exist(), and is provided
 * for backwards compatibility with old XS code. The core uses HvUSEDKEYS
 * (keys, excluding placeholdes) and HvTOTALKEYS (including placeholders)
 */
#define HvKEYS(hv)		HvUSEDKEYS(hv)
#define HvUSEDKEYS(hv)		(HvTOTALKEYS(hv) - HvPLACEHOLDERS_get(hv))
#define HvTOTALKEYS(hv)		XHvTOTALKEYS((XPVHV*)  SvANY(hv))
#define HvPLACEHOLDERS(hv)	(*Perl_hv_placeholders_p(aTHX_ (HV*)hv))
#define HvPLACEHOLDERS_get(hv)	(SvMAGIC(hv) ? Perl_hv_placeholders_get(aTHX_ (HV*)hv) : 0)
#define HvPLACEHOLDERS_set(hv,p)	Perl_hv_placeholders_set(aTHX_ (HV*)hv, p)

#define HvSHAREKEYS(hv)		(SvFLAGS(hv) & SVphv_SHAREKEYS)
#define HvSHAREKEYS_on(hv)	(SvFLAGS(hv) |= SVphv_SHAREKEYS)
#define HvSHAREKEYS_off(hv)	(SvFLAGS(hv) &= ~SVphv_SHAREKEYS)

/* This is an optimisation flag. It won't be set if all hash keys have a 0
 * flag. Currently the only flags relate to utf8.
 * Hence it won't be set if all keys are 8 bit only. It will be set if any key
 * is utf8 (including 8 bit keys that were entered as utf8, and need upgrading
 * when retrieved during iteration. It may still be set when there are no longer
 * any utf8 keys.
 * See HVhek_ENABLEHVKFLAGS for the trigger.
 */
#define HvHASKFLAGS(hv)		(SvFLAGS(hv) & SVphv_HASKFLAGS)
#define HvHASKFLAGS_on(hv)	(SvFLAGS(hv) |= SVphv_HASKFLAGS)
#define HvHASKFLAGS_off(hv)	(SvFLAGS(hv) &= ~SVphv_HASKFLAGS)

#define HvLAZYDEL(hv)		(SvFLAGS(hv) & SVphv_LAZYDEL)
#define HvLAZYDEL_on(hv)	(SvFLAGS(hv) |= SVphv_LAZYDEL)
#define HvLAZYDEL_off(hv)	(SvFLAGS(hv) &= ~SVphv_LAZYDEL)

#define HvREHASH(hv)		(SvFLAGS(hv) & SVphv_REHASH)
#define HvREHASH_on(hv)		(SvFLAGS(hv) |= SVphv_REHASH)
#define HvREHASH_off(hv)	(SvFLAGS(hv) &= ~SVphv_REHASH)

/* Maybe amagical: */
/* #define HV_AMAGICmb(hv)      (SvFLAGS(hv) & (SVpgv_badAM | SVpgv_AM)) */

#define HV_AMAGIC(hv)        (SvFLAGS(hv) &   SVpgv_AM)
#define HV_AMAGIC_on(hv)     (SvFLAGS(hv) |=  SVpgv_AM)
#define HV_AMAGIC_off(hv)    (SvFLAGS(hv) &= ~SVpgv_AM)

/*
#define HV_AMAGICbad(hv)     (SvFLAGS(hv) & SVpgv_badAM)
#define HV_badAMAGIC_on(hv)  (SvFLAGS(hv) |= SVpgv_badAM)
#define HV_badAMAGIC_off(hv) (SvFLAGS(hv) &= ~SVpgv_badAM)
*/

#define Nullhe Null(HE*)
#define HeNEXT(he)		(he)->hent_next
#define HeKEY_hek(he)		(he)->hent_hek
#define HeKEY(he)		HEK_KEY(HeKEY_hek(he))
#define HeKEY_sv(he)		(*(SV**)HeKEY(he))
#define HeKLEN(he)		HEK_LEN(HeKEY_hek(he))
#define HeKUTF8(he)  HEK_UTF8(HeKEY_hek(he))
#define HeKWASUTF8(he)  HEK_WASUTF8(HeKEY_hek(he))
#define HeKREHASH(he)  HEK_REHASH(HeKEY_hek(he))
#define HeKLEN_UTF8(he)  (HeKUTF8(he) ? -HeKLEN(he) : HeKLEN(he))
#define HeKFLAGS(he)  HEK_FLAGS(HeKEY_hek(he))
#define HeVAL(he)		(he)->hent_val
#define HeHASH(he)		HEK_HASH(HeKEY_hek(he))
#define HePV(he,lp)		((HeKLEN(he) == HEf_SVKEY) ?		\
				 SvPV(HeKEY_sv(he),lp) :		\
				 (((lp = HeKLEN(he)) >= 0) ?		\
				  HeKEY(he) : Nullch))

#define HeSVKEY(he)		((HeKEY(he) && 				\
				  HeKLEN(he) == HEf_SVKEY) ?		\
				 HeKEY_sv(he) : Nullsv)

#define HeSVKEY_force(he)	(HeKEY(he) ?				\
				 ((HeKLEN(he) == HEf_SVKEY) ?		\
				  HeKEY_sv(he) :			\
				  sv_2mortal(newSVpvn(HeKEY(he),	\
						     HeKLEN(he)))) :	\
				 &PL_sv_undef)
#define HeSVKEY_set(he,sv)	((HeKLEN(he) = HEf_SVKEY), (HeKEY_sv(he) = sv))

#define Nullhek Null(HEK*)
#define HEK_BASESIZE		STRUCT_OFFSET(HEK, hek_key[0])
#define HEK_HASH(hek)		(hek)->hek_hash
#define HEK_LEN(hek)		(hek)->hek_len
#define HEK_KEY(hek)		(hek)->hek_key
#define HEK_FLAGS(hek)	(*((unsigned char *)(HEK_KEY(hek))+HEK_LEN(hek)+1))

#define HVhek_UTF8	0x01 /* Key is utf8 encoded. */
#define HVhek_WASUTF8	0x02 /* Key is bytes here, but was supplied as utf8. */
#define HVhek_REHASH	0x04 /* This key is in an hv using a custom HASH . */
#define HVhek_FREEKEY	0x100 /* Internal flag to say key is malloc()ed.  */
#define HVhek_PLACEHOLD	0x200 /* Internal flag to create placeholder.
                               * (may change, but Storable is a core module) */
#define HVhek_MASK	0xFF

/* Which flags enable HvHASKFLAGS? Somewhat a hack on a hack, as
   HVhek_REHASH is only needed because the rehash flag has to be duplicated
   into all keys as hv_iternext has no access to the hash flags. At this
   point Storable's tests get upset, because sometimes hashes are "keyed"
   and sometimes not, depending on the order of data insertion, and whether
   it triggered rehashing. So currently HVhek_REHAS is exempt.
*/
   
#define HVhek_ENABLEHVKFLAGS	(HVhek_MASK - HVhek_REHASH)

#define HEK_UTF8(hek)		(HEK_FLAGS(hek) & HVhek_UTF8)
#define HEK_UTF8_on(hek)	(HEK_FLAGS(hek) |= HVhek_UTF8)
#define HEK_UTF8_off(hek)	(HEK_FLAGS(hek) &= ~HVhek_UTF8)
#define HEK_WASUTF8(hek)	(HEK_FLAGS(hek) & HVhek_WASUTF8)
#define HEK_WASUTF8_on(hek)	(HEK_FLAGS(hek) |= HVhek_WASUTF8)
#define HEK_WASUTF8_off(hek)	(HEK_FLAGS(hek) &= ~HVhek_WASUTF8)
#define HEK_REHASH(hek)		(HEK_FLAGS(hek) & HVhek_REHASH)
#define HEK_REHASH_on(hek)	(HEK_FLAGS(hek) |= HVhek_REHASH)

/* calculate HV array allocation */
#ifndef PERL_USE_LARGE_HV_ALLOC
/* Default to allocating the correct size - default to assuming that malloc()
   is not broken and is efficient at allocating blocks sized at powers-of-two.
*/   
#  define PERL_HV_ARRAY_ALLOC_BYTES(size) ((size) * sizeof(HE*))
#else
#  define MALLOC_OVERHEAD 16
#  define PERL_HV_ARRAY_ALLOC_BYTES(size) \
			(((size) < 64)					\
			 ? (size) * sizeof(HE*)				\
			 : (size) * sizeof(HE*) * 2 - MALLOC_OVERHEAD)
#endif

/* Flags for hv_iternext_flags.  */
#define HV_ITERNEXT_WANTPLACEHOLDERS	0x01	/* Don't skip placeholders.  */

/* available as a function in hv.c */
#define Perl_sharepvn(sv, len, hash) HEK_KEY(share_hek(sv, len, hash))
#define sharepvn(sv, len, hash)	     Perl_sharepvn(sv, len, hash)

/*
 * Local variables:
 * c-indentation-style: bsd
 * c-basic-offset: 4
 * indent-tabs-mode: t
 * End:
 *
 * ex: set ts=8 sts=4 sw=4 noet:
 */
Commit	Line	Data
a0d0e21e	1	/* hv.h
79072805	2	*
4bb101f2	3	* Copyright (C) 1991, 1992, 1993, 1996, 1997, 1998, 1999,
1d325971	4	* 2000, 2001, 2002, 2005, by Larry Wall and others
79072805	5	*
	6	* You may distribute under the terms of either the GNU General Public
	7	* License or the Artistic License, as specified in the README file.
	8	*
79072805	9	*/
79072805	10
5cbe4eec	11	/* typedefs to eliminate some typing */
79072805	12	typedef struct he HE;
ff68c719	13	typedef struct hek HEK;
79072805	14
5cbe4eec	15	/* entry in hash value chain */
79072805	16	struct he {
5cbe4eec	17	HE hent_next; / next entry in chain */
	18	HEK hent_hek; / hash key */
	19	SV hent_val; / scalar value that was hashed */
bbce6d69	20	};
bbce6d69	21
5cbe4eec	22	/* hash key -- defined separately for use as shared pointer */
ff68c719	23	struct hek {
5cbe4eec	24	U32 hek_hash; /* hash of key */
	25	I32 hek_len; /* length of hash key */
	26	char hek_key[1]; /* variable-length hash key */
e05949c7	27	/* the hash-key is \0-terminated */
1e54db1a	28	/* after the \0 there is a byte for flags, such as whether the key
1e54db1a	29	is UTF-8 */
79072805	30	};
79072805	31
bfcb3514	32
	33	/* Subject to change.
	34	Don't access this directly.
	35	*/
	36	struct xpvhv_aux {
	37	char xhv_name; / name, if a symbol table */
	38	HE xhv_eiter; / current entry of iterator */
	39	I32 xhv_riter; /* current root of iterator */
	40	};
	41
5cbe4eec	42	/* hash structure: */
6ee623d5	43	/* This structure must match the beginning of struct xpvmg in sv.h. */
79072805	44	struct xpvhv {
463ee0b2	45	char * xhv_array; /* pointer to malloced string */
	46	STRLEN xhv_fill; /* how full xhv_array currently is */
	47	STRLEN xhv_max; /* subscript of last element of xhv_array */
6ee623d5	48	IV xhv_keys; /* how many elements in the array */
65202027	49	NV xnv_nv; /* numeric value, if any */
79072805	50	MAGIC* xmg_magic; /* magic for scalar array */
	51	HV* xmg_stash; /* class package */
	52
bfcb3514	53	struct xpvhv_aux* xhv_aux;
8d2f4536	54	/* list of pm's for this package is now stored in symtab magic. */
79072805	55	};
79072805	56
5cbe4eec	57	/* hash a key */
5afd6d42	58	/* FYI: This is the "One-at-a-Time" algorithm by Bob Jenkins
	59	* from requirements by Colin Plumb.
	60	* (http://burtleburtle.net/bob/hash/doobs.html) */
	61	/* The use of a temporary pointer and the casting games
	62	* is needed to serve the dual purposes of
	63	* (a) the hashed data being interpreted as "unsigned char" (new since 5.8,
	64	* a "char" can be either signed or signed, depending on the compiler)
	65	* (b) catering for old code that uses a "char"
830b38bd	66	*
504f80c1	67	* The "hash seed" feature was added in Perl 5.8.1 to perturb the results
504f80c1	68	* to avoid "algorithmic complexity attacks".
830b38bd	69	*
	70	* If USE_HASH_SEED is defined, hash randomisation is done by default
	71	* If USE_HASH_SEED_EXPLICIT is defined, hash randomisation is done
	72	* only if the environment variable PERL_HASH_SEED is set.
	73	* For maximal control, one can define PERL_HASH_SEED.
90ce55a1	74	* (see also perl.c:perl_parse()).
5afd6d42	75	*/
830b38bd	76	#ifndef PERL_HASH_SEED
	77	# if defined(USE_HASH_SEED) \|\| defined(USE_HASH_SEED_EXPLICIT)
	78	# define PERL_HASH_SEED PL_hash_seed
	79	# else
	80	# define PERL_HASH_SEED 0
	81	# endif
504f80c1	82	#endif
bf6bd887	83	#define PERL_HASH(hash,str,len) \
bf6bd887	84	STMT_START { \
5afd6d42	85	register const char *s_PeRlHaSh_tmp = str; \
5afd6d42	86	register const unsigned char s_PeRlHaSh = (const unsigned char )s_PeRlHaSh_tmp; \
bf6bd887	87	register I32 i_PeRlHaSh = len; \
504f80c1	88	register U32 hash_PeRlHaSh = PERL_HASH_SEED; \
a6fe520e	89	while (i_PeRlHaSh--) { \
	90	hash_PeRlHaSh += *s_PeRlHaSh++; \
	91	hash_PeRlHaSh += (hash_PeRlHaSh << 10); \
	92	hash_PeRlHaSh ^= (hash_PeRlHaSh >> 6); \
	93	} \
	94	hash_PeRlHaSh += (hash_PeRlHaSh << 3); \
	95	hash_PeRlHaSh ^= (hash_PeRlHaSh >> 11); \
4fee5c71	96	(hash) = (hash_PeRlHaSh + (hash_PeRlHaSh << 15)); \
bf6bd887	97	} STMT_END
bf6bd887	98
3d78eb94	99	/* Only hv.c and mod_perl should be doing this. */
3d78eb94	100	#ifdef PERL_HASH_INTERNAL_ACCESS
4b5190b5	101	#define PERL_HASH_INTERNAL(hash,str,len) \
	102	STMT_START { \
	103	register const char *s_PeRlHaSh_tmp = str; \
	104	register const unsigned char s_PeRlHaSh = (const unsigned char )s_PeRlHaSh_tmp; \
	105	register I32 i_PeRlHaSh = len; \
008fb0c0	106	register U32 hash_PeRlHaSh = PL_rehash_seed; \
4b5190b5	107	while (i_PeRlHaSh--) { \
	108	hash_PeRlHaSh += *s_PeRlHaSh++; \
	109	hash_PeRlHaSh += (hash_PeRlHaSh << 10); \
	110	hash_PeRlHaSh ^= (hash_PeRlHaSh >> 6); \
	111	} \
	112	hash_PeRlHaSh += (hash_PeRlHaSh << 3); \
	113	hash_PeRlHaSh ^= (hash_PeRlHaSh >> 11); \
	114	(hash) = (hash_PeRlHaSh + (hash_PeRlHaSh << 15)); \
	115	} STMT_END
	116	#endif
	117
954c1994	118	/*
ccfc67b7	119	=head1 Hash Manipulation Functions
ccfc67b7	120
954c1994	121	=for apidoc AmU\|\|HEf_SVKEY
954c1994	122	This flag, used in the length slot of hash entries and magic structures,
d1be9408	123	specifies the structure contains an C<SV> pointer where a C<char> pointer
954c1994	124	is to be expected. (For information only--not to be used).
954c1994	125
ccfc67b7	126	=head1 Handy Values
ccfc67b7	127
954c1994	128	=for apidoc AmU\|\|Nullhv
	129	Null HV pointer.
	130
ccfc67b7	131	=head1 Hash Manipulation Functions
ccfc67b7	132
954c1994	133	=for apidoc Am\|char\|HvNAME\|HV stash
	134	Returns the package name of a stash. See C<SvSTASH>, C<CvSTASH>.
	135
	136	=for apidoc Am\|void\|HeKEY\|HE he
	137	Returns the actual pointer stored in the key slot of the hash entry. The
	138	pointer may be either C<char> or C<SV>, depending on the value of
	139	C<HeKLEN()>. Can be assigned to. The C<HePV()> or C<HeSVKEY()> macros are
	140	usually preferable for finding the value of a key.
	141
	142	=for apidoc Am\|STRLEN\|HeKLEN\|HE* he
	143	If this is negative, and amounts to C<HEf_SVKEY>, it indicates the entry
	144	holds an C<SV*> key. Otherwise, holds the actual length of the key. Can
	145	be assigned to. The C<HePV()> macro is usually preferable for finding key
	146	lengths.
	147
	148	=for apidoc Am\|SV\|HeVAL\|HE he
	149	Returns the value slot (type C<SV*>) stored in the hash entry.
	150
	151	=for apidoc Am\|U32\|HeHASH\|HE* he
	152	Returns the computed hash stored in the hash entry.
	153
	154	=for apidoc Am\|char\|HePV\|HE he\|STRLEN len
	155	Returns the key slot of the hash entry as a C<char*> value, doing any
	156	necessary dereferencing of possibly C<SV*> keys. The length of the string
	157	is placed in C<len> (this is a macro, so do I<not> use C<&len>). If you do
	158	not care about what the length of the key is, you may use the global
	159	variable C<PL_na>, though this is rather less efficient than using a local
	160	variable. Remember though, that hash keys in perl are free to contain
	161	embedded nulls, so using C<strlen()> or similar is not a good way to find
	162	the length of hash keys. This is very similar to the C<SvPV()> macro
	163	described elsewhere in this document.
	164
	165	=for apidoc Am\|SV\|HeSVKEY\|HE he
	166	Returns the key as an C<SV*>, or C<Nullsv> if the hash entry does not
	167	contain an C<SV*> key.
	168
	169	=for apidoc Am\|SV\|HeSVKEY_force\|HE he
	170	Returns the key as an C<SV*>. Will create and return a temporary mortal
	171	C<SV> if the hash entry contains only a C<char> key.
	172
	173	=for apidoc Am\|SV\|HeSVKEY_set\|HE he\|SV* sv
	174	Sets the key to a given C<SV*>, taking care to set the appropriate flags to
	175	indicate the presence of an C<SV*> key, and returns the same
	176	C<SV*>.
	177
	178	=cut
	179	*/
bf6bd887	180
bf5b86ae	181	/* these hash entry flags ride on hent_klen (for use only in magic/tied HVs) */
d1be9408	182	#define HEf_SVKEY -2 /* hent_key is an SV* */
bf6bd887	183
bf6bd887	184
79072805	185	#define Nullhv Null(HV*)
4efcf9a2	186	#define HvARRAY(hv) ((HE*)&((XPVHV) SvANY(hv))->xhv_array)
79072805	187	#define HvFILL(hv) ((XPVHV*) SvANY(hv))->xhv_fill
463ee0b2	188	#define HvMAX(hv) ((XPVHV*) SvANY(hv))->xhv_max
bfcb3514	189	#define HvRITER(hv) (Perl_hv_riter_p(aTHX_ (HV)(hv)))
	190	#define HvEITER(hv) (Perl_hv_eiter_p(aTHX_ (HV)(hv)))
	191	#define HvRITER_set(hv,r) Perl_hv_riter_set(aTHX_ (HV*)(hv), r)
	192	#define HvEITER_set(hv,e) Perl_hv_eiter_set(aTHX_ (HV*)(hv), e)
	193	#define HvRITER_get(hv) (((XPVHV *)SvANY(hv))->xhv_aux ? \
	194	((struct xpvhv_aux)((XPVHV )SvANY(hv))->xhv_aux)->xhv_riter : -1)
	195	#define HvEITER_get(hv) (((XPVHV *)SvANY(hv))->xhv_aux ? \
	196	((struct xpvhv_aux )((XPVHV )SvANY(hv))->xhv_aux)->xhv_eiter : 0)
	197	#define HvNAME(hv) (Perl_hv_name_p(aTHX_ (HV)hv))
	198	/* FIXME - all of these should use a UTF8 aware API, which should also involve
	199	getting the length. */
	200	#define HvNAME_get(hv) (((XPVHV *)SvANY(hv))->xhv_aux ? \
	201	((struct xpvhv_aux )((XPVHV )SvANY(hv))->xhv_aux)->xhv_name : 0)
a0d0e21e	202
8aacddc1	203	/* the number of keys (including any placeholers) */
	204	#define XHvTOTALKEYS(xhv) ((xhv)->xhv_keys)
	205
8aacddc1	206	/*
	207	* HvKEYS gets the number of keys that actually exist(), and is provided
	208	* for backwards compatibility with old XS code. The core uses HvUSEDKEYS
	209	* (keys, excluding placeholdes) and HvTOTALKEYS (including placeholders)
	210	*/
ca732855	211	#define HvKEYS(hv) HvUSEDKEYS(hv)
ca732855	212	#define HvUSEDKEYS(hv) (HvTOTALKEYS(hv) - HvPLACEHOLDERS_get(hv))
8aacddc1	213	#define HvTOTALKEYS(hv) XHvTOTALKEYS((XPVHV*) SvANY(hv))
ca732855	214	#define HvPLACEHOLDERS(hv) (Perl_hv_placeholders_p(aTHX_ (HV)hv))
	215	#define HvPLACEHOLDERS_get(hv) (SvMAGIC(hv) ? Perl_hv_placeholders_get(aTHX_ (HV*)hv) : 0)
	216	#define HvPLACEHOLDERS_set(hv,p) Perl_hv_placeholders_set(aTHX_ (HV*)hv, p)
8aacddc1	217
bf6bd887	218	#define HvSHAREKEYS(hv) (SvFLAGS(hv) & SVphv_SHAREKEYS)
	219	#define HvSHAREKEYS_on(hv) (SvFLAGS(hv) \|= SVphv_SHAREKEYS)
	220	#define HvSHAREKEYS_off(hv) (SvFLAGS(hv) &= ~SVphv_SHAREKEYS)
	221
19692e8d	222	/* This is an optimisation flag. It won't be set if all hash keys have a 0
	223	* flag. Currently the only flags relate to utf8.
	224	* Hence it won't be set if all keys are 8 bit only. It will be set if any key
	225	* is utf8 (including 8 bit keys that were entered as utf8, and need upgrading
	226	* when retrieved during iteration. It may still be set when there are no longer
	227	* any utf8 keys.
fdcd69b6	228	* See HVhek_ENABLEHVKFLAGS for the trigger.
19692e8d	229	*/
	230	#define HvHASKFLAGS(hv) (SvFLAGS(hv) & SVphv_HASKFLAGS)
	231	#define HvHASKFLAGS_on(hv) (SvFLAGS(hv) \|= SVphv_HASKFLAGS)
	232	#define HvHASKFLAGS_off(hv) (SvFLAGS(hv) &= ~SVphv_HASKFLAGS)
574c8022	233
bf5b86ae	234	#define HvLAZYDEL(hv) (SvFLAGS(hv) & SVphv_LAZYDEL)
	235	#define HvLAZYDEL_on(hv) (SvFLAGS(hv) \|= SVphv_LAZYDEL)
	236	#define HvLAZYDEL_off(hv) (SvFLAGS(hv) &= ~SVphv_LAZYDEL)
	237
4b5190b5	238	#define HvREHASH(hv) (SvFLAGS(hv) & SVphv_REHASH)
	239	#define HvREHASH_on(hv) (SvFLAGS(hv) \|= SVphv_REHASH)
	240	#define HvREHASH_off(hv) (SvFLAGS(hv) &= ~SVphv_REHASH)
	241
a0d0e21e	242	/* Maybe amagical: */
	243	/* #define HV_AMAGICmb(hv) (SvFLAGS(hv) & (SVpgv_badAM \| SVpgv_AM)) */
	244
	245	#define HV_AMAGIC(hv) (SvFLAGS(hv) & SVpgv_AM)
	246	#define HV_AMAGIC_on(hv) (SvFLAGS(hv) \|= SVpgv_AM)
	247	#define HV_AMAGIC_off(hv) (SvFLAGS(hv) &= ~SVpgv_AM)
	248
	249	/*
	250	#define HV_AMAGICbad(hv) (SvFLAGS(hv) & SVpgv_badAM)
	251	#define HV_badAMAGIC_on(hv) (SvFLAGS(hv) \|= SVpgv_badAM)
	252	#define HV_badAMAGIC_off(hv) (SvFLAGS(hv) &= ~SVpgv_badAM)
	253	*/
bf6bd887	254
	255	#define Nullhe Null(HE*)
	256	#define HeNEXT(he) (he)->hent_next
ff68c719	257	#define HeKEY_hek(he) (he)->hent_hek
ff68c719	258	#define HeKEY(he) HEK_KEY(HeKEY_hek(he))
bbce6d69	259	#define HeKEY_sv(he) ((SV*)HeKEY(he))
ff68c719	260	#define HeKLEN(he) HEK_LEN(HeKEY_hek(he))
da58a35d	261	#define HeKUTF8(he) HEK_UTF8(HeKEY_hek(he))
19692e8d	262	#define HeKWASUTF8(he) HEK_WASUTF8(HeKEY_hek(he))
4b5190b5	263	#define HeKREHASH(he) HEK_REHASH(HeKEY_hek(he))
da58a35d	264	#define HeKLEN_UTF8(he) (HeKUTF8(he) ? -HeKLEN(he) : HeKLEN(he))
19692e8d	265	#define HeKFLAGS(he) HEK_FLAGS(HeKEY_hek(he))
bf6bd887	266	#define HeVAL(he) (he)->hent_val
ff68c719	267	#define HeHASH(he) HEK_HASH(HeKEY_hek(he))
1e422769	268	#define HePV(he,lp) ((HeKLEN(he) == HEf_SVKEY) ? \
	269	SvPV(HeKEY_sv(he),lp) : \
	270	(((lp = HeKLEN(he)) >= 0) ? \
	271	HeKEY(he) : Nullch))
	272
bbce6d69	273	#define HeSVKEY(he) ((HeKEY(he) && \
	274	HeKLEN(he) == HEf_SVKEY) ? \
	275	HeKEY_sv(he) : Nullsv)
	276
	277	#define HeSVKEY_force(he) (HeKEY(he) ? \
	278	((HeKLEN(he) == HEf_SVKEY) ? \
	279	HeKEY_sv(he) : \
79cb57f6	280	sv_2mortal(newSVpvn(HeKEY(he), \
bbce6d69	281	HeKLEN(he)))) : \
3280af22	282	&PL_sv_undef)
1e422769	283	#define HeSVKEY_set(he,sv) ((HeKLEN(he) = HEf_SVKEY), (HeKEY_sv(he) = sv))
bbce6d69	284
ff68c719	285	#define Nullhek Null(HEK*)
71be2cbc	286	#define HEK_BASESIZE STRUCT_OFFSET(HEK, hek_key[0])
ff68c719	287	#define HEK_HASH(hek) (hek)->hek_hash
	288	#define HEK_LEN(hek) (hek)->hek_len
	289	#define HEK_KEY(hek) (hek)->hek_key
19692e8d	290	#define HEK_FLAGS(hek) (((unsigned char )(HEK_KEY(hek))+HEK_LEN(hek)+1))
	291
	292	#define HVhek_UTF8 0x01 /* Key is utf8 encoded. */
	293	#define HVhek_WASUTF8 0x02 /* Key is bytes here, but was supplied as utf8. */
4b5190b5	294	#define HVhek_REHASH 0x04 /* This key is in an hv using a custom HASH . */
19692e8d	295	#define HVhek_FREEKEY 0x100 /* Internal flag to say key is malloc()ed. */
e16e2ff8	296	#define HVhek_PLACEHOLD 0x200 /* Internal flag to create placeholder.
e16e2ff8	297	* (may change, but Storable is a core module) */
19692e8d	298	#define HVhek_MASK 0xFF
19692e8d	299
fdcd69b6	300	/* Which flags enable HvHASKFLAGS? Somewhat a hack on a hack, as
	301	HVhek_REHASH is only needed because the rehash flag has to be duplicated
	302	into all keys as hv_iternext has no access to the hash flags. At this
	303	point Storable's tests get upset, because sometimes hashes are "keyed"
	304	and sometimes not, depending on the order of data insertion, and whether
	305	it triggered rehashing. So currently HVhek_REHAS is exempt.
	306	*/
	307
	308	#define HVhek_ENABLEHVKFLAGS (HVhek_MASK - HVhek_REHASH)
	309
19692e8d	310	#define HEK_UTF8(hek) (HEK_FLAGS(hek) & HVhek_UTF8)
	311	#define HEK_UTF8_on(hek) (HEK_FLAGS(hek) \|= HVhek_UTF8)
	312	#define HEK_UTF8_off(hek) (HEK_FLAGS(hek) &= ~HVhek_UTF8)
	313	#define HEK_WASUTF8(hek) (HEK_FLAGS(hek) & HVhek_WASUTF8)
	314	#define HEK_WASUTF8_on(hek) (HEK_FLAGS(hek) \|= HVhek_WASUTF8)
	315	#define HEK_WASUTF8_off(hek) (HEK_FLAGS(hek) &= ~HVhek_WASUTF8)
4b5190b5	316	#define HEK_REHASH(hek) (HEK_FLAGS(hek) & HVhek_REHASH)
4b5190b5	317	#define HEK_REHASH_on(hek) (HEK_FLAGS(hek) \|= HVhek_REHASH)
d18c6117	318
5cbe4eec	319	/* calculate HV array allocation */
36768cf4	320	#ifndef PERL_USE_LARGE_HV_ALLOC
	321	/* Default to allocating the correct size - default to assuming that malloc()
	322	is not broken and is efficient at allocating blocks sized at powers-of-two.
	323	*/
d18c6117	324	# define PERL_HV_ARRAY_ALLOC_BYTES(size) ((size) * sizeof(HE*))
	325	#else
	326	# define MALLOC_OVERHEAD 16
	327	# define PERL_HV_ARRAY_ALLOC_BYTES(size) \
	328	(((size) < 64) \
	329	? (size) * sizeof(HE*) \
	330	: (size) * sizeof(HE) 2 - MALLOC_OVERHEAD)
	331	#endif
37d85e3a	332
e16e2ff8	333	/* Flags for hv_iternext_flags. */
	334	#define HV_ITERNEXT_WANTPLACEHOLDERS 0x01 /* Don't skip placeholders. */
	335
37d85e3a	336	/* available as a function in hv.c */
	337	#define Perl_sharepvn(sv, len, hash) HEK_KEY(share_hek(sv, len, hash))
	338	#define sharepvn(sv, len, hash) Perl_sharepvn(sv, len, hash)
bfcb3514	339
	340	/*
	341	* Local variables:
	342	* c-indentation-style: bsd
	343	* c-basic-offset: 4
	344	* indent-tabs-mode: t
	345	* End:
	346	*
	347	* ex: set ts=8 sts=4 sw=4 noet:
	348	*/