[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 {
    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***)&((hv)->sv_u.sv_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	STRLEN xhv_fill; /* how full xhv_array currently is */
463ee0b2	46	STRLEN xhv_max; /* subscript of last element of xhv_array */
6ee623d5	47	IV xhv_keys; /* how many elements in the array */
65202027	48	NV xnv_nv; /* numeric value, if any */
79072805	49	MAGIC* xmg_magic; /* magic for scalar array */
	50	HV* xmg_stash; /* class package */
	51
bfcb3514	52	struct xpvhv_aux* xhv_aux;
8d2f4536	53	/* list of pm's for this package is now stored in symtab magic. */
79072805	54	};
79072805	55
5cbe4eec	56	/* hash a key */
5afd6d42	57	/* FYI: This is the "One-at-a-Time" algorithm by Bob Jenkins
	58	* from requirements by Colin Plumb.
	59	* (http://burtleburtle.net/bob/hash/doobs.html) */
	60	/* The use of a temporary pointer and the casting games
	61	* is needed to serve the dual purposes of
	62	* (a) the hashed data being interpreted as "unsigned char" (new since 5.8,
	63	* a "char" can be either signed or signed, depending on the compiler)
	64	* (b) catering for old code that uses a "char"
830b38bd	65	*
504f80c1	66	* The "hash seed" feature was added in Perl 5.8.1 to perturb the results
504f80c1	67	* to avoid "algorithmic complexity attacks".
830b38bd	68	*
	69	* If USE_HASH_SEED is defined, hash randomisation is done by default
	70	* If USE_HASH_SEED_EXPLICIT is defined, hash randomisation is done
	71	* only if the environment variable PERL_HASH_SEED is set.
	72	* For maximal control, one can define PERL_HASH_SEED.
90ce55a1	73	* (see also perl.c:perl_parse()).
5afd6d42	74	*/
830b38bd	75	#ifndef PERL_HASH_SEED
	76	# if defined(USE_HASH_SEED) \|\| defined(USE_HASH_SEED_EXPLICIT)
	77	# define PERL_HASH_SEED PL_hash_seed
	78	# else
	79	# define PERL_HASH_SEED 0
	80	# endif
504f80c1	81	#endif
bf6bd887	82	#define PERL_HASH(hash,str,len) \
bf6bd887	83	STMT_START { \
5afd6d42	84	register const char *s_PeRlHaSh_tmp = str; \
5afd6d42	85	register const unsigned char s_PeRlHaSh = (const unsigned char )s_PeRlHaSh_tmp; \
bf6bd887	86	register I32 i_PeRlHaSh = len; \
504f80c1	87	register U32 hash_PeRlHaSh = PERL_HASH_SEED; \
a6fe520e	88	while (i_PeRlHaSh--) { \
	89	hash_PeRlHaSh += *s_PeRlHaSh++; \
	90	hash_PeRlHaSh += (hash_PeRlHaSh << 10); \
	91	hash_PeRlHaSh ^= (hash_PeRlHaSh >> 6); \
	92	} \
	93	hash_PeRlHaSh += (hash_PeRlHaSh << 3); \
	94	hash_PeRlHaSh ^= (hash_PeRlHaSh >> 11); \
4fee5c71	95	(hash) = (hash_PeRlHaSh + (hash_PeRlHaSh << 15)); \
bf6bd887	96	} STMT_END
bf6bd887	97
3d78eb94	98	/* Only hv.c and mod_perl should be doing this. */
3d78eb94	99	#ifdef PERL_HASH_INTERNAL_ACCESS
4b5190b5	100	#define PERL_HASH_INTERNAL(hash,str,len) \
	101	STMT_START { \
	102	register const char *s_PeRlHaSh_tmp = str; \
	103	register const unsigned char s_PeRlHaSh = (const unsigned char )s_PeRlHaSh_tmp; \
	104	register I32 i_PeRlHaSh = len; \
008fb0c0	105	register U32 hash_PeRlHaSh = PL_rehash_seed; \
4b5190b5	106	while (i_PeRlHaSh--) { \
	107	hash_PeRlHaSh += *s_PeRlHaSh++; \
	108	hash_PeRlHaSh += (hash_PeRlHaSh << 10); \
	109	hash_PeRlHaSh ^= (hash_PeRlHaSh >> 6); \
	110	} \
	111	hash_PeRlHaSh += (hash_PeRlHaSh << 3); \
	112	hash_PeRlHaSh ^= (hash_PeRlHaSh >> 11); \
	113	(hash) = (hash_PeRlHaSh + (hash_PeRlHaSh << 15)); \
	114	} STMT_END
	115	#endif
	116
954c1994	117	/*
ccfc67b7	118	=head1 Hash Manipulation Functions
ccfc67b7	119
954c1994	120	=for apidoc AmU\|\|HEf_SVKEY
954c1994	121	This flag, used in the length slot of hash entries and magic structures,
d1be9408	122	specifies the structure contains an C<SV> pointer where a C<char> pointer
954c1994	123	is to be expected. (For information only--not to be used).
954c1994	124
ccfc67b7	125	=head1 Handy Values
ccfc67b7	126
954c1994	127	=for apidoc AmU\|\|Nullhv
	128	Null HV pointer.
	129
ccfc67b7	130	=head1 Hash Manipulation Functions
ccfc67b7	131
954c1994	132	=for apidoc Am\|char\|HvNAME\|HV stash
	133	Returns the package name of a stash. See C<SvSTASH>, C<CvSTASH>.
	134
	135	=for apidoc Am\|void\|HeKEY\|HE he
	136	Returns the actual pointer stored in the key slot of the hash entry. The
	137	pointer may be either C<char> or C<SV>, depending on the value of
	138	C<HeKLEN()>. Can be assigned to. The C<HePV()> or C<HeSVKEY()> macros are
	139	usually preferable for finding the value of a key.
	140
	141	=for apidoc Am\|STRLEN\|HeKLEN\|HE* he
	142	If this is negative, and amounts to C<HEf_SVKEY>, it indicates the entry
	143	holds an C<SV*> key. Otherwise, holds the actual length of the key. Can
	144	be assigned to. The C<HePV()> macro is usually preferable for finding key
	145	lengths.
	146
	147	=for apidoc Am\|SV\|HeVAL\|HE he
	148	Returns the value slot (type C<SV*>) stored in the hash entry.
	149
	150	=for apidoc Am\|U32\|HeHASH\|HE* he
	151	Returns the computed hash stored in the hash entry.
	152
	153	=for apidoc Am\|char\|HePV\|HE he\|STRLEN len
	154	Returns the key slot of the hash entry as a C<char*> value, doing any
	155	necessary dereferencing of possibly C<SV*> keys. The length of the string
	156	is placed in C<len> (this is a macro, so do I<not> use C<&len>). If you do
	157	not care about what the length of the key is, you may use the global
	158	variable C<PL_na>, though this is rather less efficient than using a local
	159	variable. Remember though, that hash keys in perl are free to contain
	160	embedded nulls, so using C<strlen()> or similar is not a good way to find
	161	the length of hash keys. This is very similar to the C<SvPV()> macro
	162	described elsewhere in this document.
	163
	164	=for apidoc Am\|SV\|HeSVKEY\|HE he
	165	Returns the key as an C<SV*>, or C<Nullsv> if the hash entry does not
	166	contain an C<SV*> key.
	167
	168	=for apidoc Am\|SV\|HeSVKEY_force\|HE he
	169	Returns the key as an C<SV*>. Will create and return a temporary mortal
	170	C<SV> if the hash entry contains only a C<char> key.
	171
	172	=for apidoc Am\|SV\|HeSVKEY_set\|HE he\|SV* sv
	173	Sets the key to a given C<SV*>, taking care to set the appropriate flags to
	174	indicate the presence of an C<SV*> key, and returns the same
	175	C<SV*>.
	176
	177	=cut
	178	*/
bf6bd887	179
bf5b86ae	180	/* these hash entry flags ride on hent_klen (for use only in magic/tied HVs) */
d1be9408	181	#define HEf_SVKEY -2 /* hent_key is an SV* */
bf6bd887	182
bf6bd887	183
79072805	184	#define Nullhv Null(HV*)
7b2c381c	185	#define HvARRAY(hv) ((HE**)&((hv)->sv_u.sv_array))
79072805	186	#define HvFILL(hv) ((XPVHV*) SvANY(hv))->xhv_fill
463ee0b2	187	#define HvMAX(hv) ((XPVHV*) SvANY(hv))->xhv_max
bfcb3514	188	#define HvRITER(hv) (Perl_hv_riter_p(aTHX_ (HV)(hv)))
	189	#define HvEITER(hv) (Perl_hv_eiter_p(aTHX_ (HV)(hv)))
	190	#define HvRITER_set(hv,r) Perl_hv_riter_set(aTHX_ (HV*)(hv), r)
	191	#define HvEITER_set(hv,e) Perl_hv_eiter_set(aTHX_ (HV*)(hv), e)
	192	#define HvRITER_get(hv) (((XPVHV *)SvANY(hv))->xhv_aux ? \
	193	((struct xpvhv_aux)((XPVHV )SvANY(hv))->xhv_aux)->xhv_riter : -1)
	194	#define HvEITER_get(hv) (((XPVHV *)SvANY(hv))->xhv_aux ? \
	195	((struct xpvhv_aux )((XPVHV )SvANY(hv))->xhv_aux)->xhv_eiter : 0)
	196	#define HvNAME(hv) (Perl_hv_name_p(aTHX_ (HV)hv))
	197	/* FIXME - all of these should use a UTF8 aware API, which should also involve
	198	getting the length. */
	199	#define HvNAME_get(hv) (((XPVHV *)SvANY(hv))->xhv_aux ? \
	200	((struct xpvhv_aux )((XPVHV )SvANY(hv))->xhv_aux)->xhv_name : 0)
a0d0e21e	201
8aacddc1	202	/* the number of keys (including any placeholers) */
	203	#define XHvTOTALKEYS(xhv) ((xhv)->xhv_keys)
	204
8aacddc1	205	/*
	206	* HvKEYS gets the number of keys that actually exist(), and is provided
	207	* for backwards compatibility with old XS code. The core uses HvUSEDKEYS
	208	* (keys, excluding placeholdes) and HvTOTALKEYS (including placeholders)
	209	*/
ca732855	210	#define HvKEYS(hv) HvUSEDKEYS(hv)
ca732855	211	#define HvUSEDKEYS(hv) (HvTOTALKEYS(hv) - HvPLACEHOLDERS_get(hv))
8aacddc1	212	#define HvTOTALKEYS(hv) XHvTOTALKEYS((XPVHV*) SvANY(hv))
ca732855	213	#define HvPLACEHOLDERS(hv) (Perl_hv_placeholders_p(aTHX_ (HV)hv))
	214	#define HvPLACEHOLDERS_get(hv) (SvMAGIC(hv) ? Perl_hv_placeholders_get(aTHX_ (HV*)hv) : 0)
	215	#define HvPLACEHOLDERS_set(hv,p) Perl_hv_placeholders_set(aTHX_ (HV*)hv, p)
8aacddc1	216
bf6bd887	217	#define HvSHAREKEYS(hv) (SvFLAGS(hv) & SVphv_SHAREKEYS)
	218	#define HvSHAREKEYS_on(hv) (SvFLAGS(hv) \|= SVphv_SHAREKEYS)
	219	#define HvSHAREKEYS_off(hv) (SvFLAGS(hv) &= ~SVphv_SHAREKEYS)
	220
19692e8d	221	/* This is an optimisation flag. It won't be set if all hash keys have a 0
	222	* flag. Currently the only flags relate to utf8.
	223	* Hence it won't be set if all keys are 8 bit only. It will be set if any key
	224	* is utf8 (including 8 bit keys that were entered as utf8, and need upgrading
	225	* when retrieved during iteration. It may still be set when there are no longer
	226	* any utf8 keys.
fdcd69b6	227	* See HVhek_ENABLEHVKFLAGS for the trigger.
19692e8d	228	*/
	229	#define HvHASKFLAGS(hv) (SvFLAGS(hv) & SVphv_HASKFLAGS)
	230	#define HvHASKFLAGS_on(hv) (SvFLAGS(hv) \|= SVphv_HASKFLAGS)
	231	#define HvHASKFLAGS_off(hv) (SvFLAGS(hv) &= ~SVphv_HASKFLAGS)
574c8022	232
bf5b86ae	233	#define HvLAZYDEL(hv) (SvFLAGS(hv) & SVphv_LAZYDEL)
	234	#define HvLAZYDEL_on(hv) (SvFLAGS(hv) \|= SVphv_LAZYDEL)
	235	#define HvLAZYDEL_off(hv) (SvFLAGS(hv) &= ~SVphv_LAZYDEL)
	236
4b5190b5	237	#define HvREHASH(hv) (SvFLAGS(hv) & SVphv_REHASH)
	238	#define HvREHASH_on(hv) (SvFLAGS(hv) \|= SVphv_REHASH)
	239	#define HvREHASH_off(hv) (SvFLAGS(hv) &= ~SVphv_REHASH)
	240
a0d0e21e	241	/* Maybe amagical: */
	242	/* #define HV_AMAGICmb(hv) (SvFLAGS(hv) & (SVpgv_badAM \| SVpgv_AM)) */
	243
	244	#define HV_AMAGIC(hv) (SvFLAGS(hv) & SVpgv_AM)
	245	#define HV_AMAGIC_on(hv) (SvFLAGS(hv) \|= SVpgv_AM)
	246	#define HV_AMAGIC_off(hv) (SvFLAGS(hv) &= ~SVpgv_AM)
	247
	248	/*
	249	#define HV_AMAGICbad(hv) (SvFLAGS(hv) & SVpgv_badAM)
	250	#define HV_badAMAGIC_on(hv) (SvFLAGS(hv) \|= SVpgv_badAM)
	251	#define HV_badAMAGIC_off(hv) (SvFLAGS(hv) &= ~SVpgv_badAM)
	252	*/
bf6bd887	253
	254	#define Nullhe Null(HE*)
	255	#define HeNEXT(he) (he)->hent_next
ff68c719	256	#define HeKEY_hek(he) (he)->hent_hek
ff68c719	257	#define HeKEY(he) HEK_KEY(HeKEY_hek(he))
bbce6d69	258	#define HeKEY_sv(he) ((SV*)HeKEY(he))
ff68c719	259	#define HeKLEN(he) HEK_LEN(HeKEY_hek(he))
da58a35d	260	#define HeKUTF8(he) HEK_UTF8(HeKEY_hek(he))
19692e8d	261	#define HeKWASUTF8(he) HEK_WASUTF8(HeKEY_hek(he))
4b5190b5	262	#define HeKREHASH(he) HEK_REHASH(HeKEY_hek(he))
da58a35d	263	#define HeKLEN_UTF8(he) (HeKUTF8(he) ? -HeKLEN(he) : HeKLEN(he))
19692e8d	264	#define HeKFLAGS(he) HEK_FLAGS(HeKEY_hek(he))
bf6bd887	265	#define HeVAL(he) (he)->hent_val
ff68c719	266	#define HeHASH(he) HEK_HASH(HeKEY_hek(he))
1e422769	267	#define HePV(he,lp) ((HeKLEN(he) == HEf_SVKEY) ? \
	268	SvPV(HeKEY_sv(he),lp) : \
	269	(((lp = HeKLEN(he)) >= 0) ? \
	270	HeKEY(he) : Nullch))
	271
bbce6d69	272	#define HeSVKEY(he) ((HeKEY(he) && \
	273	HeKLEN(he) == HEf_SVKEY) ? \
	274	HeKEY_sv(he) : Nullsv)
	275
	276	#define HeSVKEY_force(he) (HeKEY(he) ? \
	277	((HeKLEN(he) == HEf_SVKEY) ? \
	278	HeKEY_sv(he) : \
79cb57f6	279	sv_2mortal(newSVpvn(HeKEY(he), \
bbce6d69	280	HeKLEN(he)))) : \
3280af22	281	&PL_sv_undef)
1e422769	282	#define HeSVKEY_set(he,sv) ((HeKLEN(he) = HEf_SVKEY), (HeKEY_sv(he) = sv))
bbce6d69	283
ff68c719	284	#define Nullhek Null(HEK*)
71be2cbc	285	#define HEK_BASESIZE STRUCT_OFFSET(HEK, hek_key[0])
ff68c719	286	#define HEK_HASH(hek) (hek)->hek_hash
	287	#define HEK_LEN(hek) (hek)->hek_len
	288	#define HEK_KEY(hek) (hek)->hek_key
19692e8d	289	#define HEK_FLAGS(hek) (((unsigned char )(HEK_KEY(hek))+HEK_LEN(hek)+1))
	290
	291	#define HVhek_UTF8 0x01 /* Key is utf8 encoded. */
	292	#define HVhek_WASUTF8 0x02 /* Key is bytes here, but was supplied as utf8. */
4b5190b5	293	#define HVhek_REHASH 0x04 /* This key is in an hv using a custom HASH . */
19692e8d	294	#define HVhek_FREEKEY 0x100 /* Internal flag to say key is malloc()ed. */
e16e2ff8	295	#define HVhek_PLACEHOLD 0x200 /* Internal flag to create placeholder.
e16e2ff8	296	* (may change, but Storable is a core module) */
19692e8d	297	#define HVhek_MASK 0xFF
19692e8d	298
fdcd69b6	299	/* Which flags enable HvHASKFLAGS? Somewhat a hack on a hack, as
	300	HVhek_REHASH is only needed because the rehash flag has to be duplicated
	301	into all keys as hv_iternext has no access to the hash flags. At this
	302	point Storable's tests get upset, because sometimes hashes are "keyed"
	303	and sometimes not, depending on the order of data insertion, and whether
	304	it triggered rehashing. So currently HVhek_REHAS is exempt.
	305	*/
	306
	307	#define HVhek_ENABLEHVKFLAGS (HVhek_MASK - HVhek_REHASH)
	308
19692e8d	309	#define HEK_UTF8(hek) (HEK_FLAGS(hek) & HVhek_UTF8)
	310	#define HEK_UTF8_on(hek) (HEK_FLAGS(hek) \|= HVhek_UTF8)
	311	#define HEK_UTF8_off(hek) (HEK_FLAGS(hek) &= ~HVhek_UTF8)
	312	#define HEK_WASUTF8(hek) (HEK_FLAGS(hek) & HVhek_WASUTF8)
	313	#define HEK_WASUTF8_on(hek) (HEK_FLAGS(hek) \|= HVhek_WASUTF8)
	314	#define HEK_WASUTF8_off(hek) (HEK_FLAGS(hek) &= ~HVhek_WASUTF8)
4b5190b5	315	#define HEK_REHASH(hek) (HEK_FLAGS(hek) & HVhek_REHASH)
4b5190b5	316	#define HEK_REHASH_on(hek) (HEK_FLAGS(hek) \|= HVhek_REHASH)
d18c6117	317
5cbe4eec	318	/* calculate HV array allocation */
36768cf4	319	#ifndef PERL_USE_LARGE_HV_ALLOC
	320	/* Default to allocating the correct size - default to assuming that malloc()
	321	is not broken and is efficient at allocating blocks sized at powers-of-two.
	322	*/
d18c6117	323	# define PERL_HV_ARRAY_ALLOC_BYTES(size) ((size) * sizeof(HE*))
	324	#else
	325	# define MALLOC_OVERHEAD 16
	326	# define PERL_HV_ARRAY_ALLOC_BYTES(size) \
	327	(((size) < 64) \
	328	? (size) * sizeof(HE*) \
	329	: (size) * sizeof(HE) 2 - MALLOC_OVERHEAD)
	330	#endif
37d85e3a	331
e16e2ff8	332	/* Flags for hv_iternext_flags. */
	333	#define HV_ITERNEXT_WANTPLACEHOLDERS 0x01 /* Don't skip placeholders. */
	334
37d85e3a	335	/* available as a function in hv.c */
	336	#define Perl_sharepvn(sv, len, hash) HEK_KEY(share_hek(sv, len, hash))
	337	#define sharepvn(sv, len, hash) Perl_sharepvn(sv, len, hash)
bfcb3514	338
	339	/*
	340	* Local variables:
	341	* c-indentation-style: bsd
	342	* c-basic-offset: 4
	343	* indent-tabs-mode: t
	344	* End:
	345	*
	346	* ex: set ts=8 sts=4 sw=4 noet:
	347	*/