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[p5sagit/p5-mst-13.2.git] / hv.h
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a0d0e21e 1/* hv.h
79072805 2 *
3818b22b 3 * Copyright (c) 1991-2000, Larry Wall
79072805 4 *
5 * You may distribute under the terms of either the GNU General Public
6 * License or the Artistic License, as specified in the README file.
7 *
79072805 8 */
9
79072805 10typedef struct he HE;
ff68c719 11typedef struct hek HEK;
79072805 12
13struct he {
14 HE *hent_next;
ff68c719 15 HEK *hent_hek;
79072805 16 SV *hent_val;
bbce6d69 17};
18
ff68c719 19struct hek {
20 U32 hek_hash;
21 I32 hek_len;
22 char hek_key[1];
79072805 23};
24
6ee623d5 25/* This structure must match the beginning of struct xpvmg in sv.h. */
79072805 26struct xpvhv {
463ee0b2 27 char * xhv_array; /* pointer to malloced string */
28 STRLEN xhv_fill; /* how full xhv_array currently is */
29 STRLEN xhv_max; /* subscript of last element of xhv_array */
6ee623d5 30 IV xhv_keys; /* how many elements in the array */
65202027 31 NV xnv_nv; /* numeric value, if any */
79072805 32 MAGIC* xmg_magic; /* magic for scalar array */
33 HV* xmg_stash; /* class package */
34
79072805 35 I32 xhv_riter; /* current root of iterator */
36 HE *xhv_eiter; /* current entry of iterator */
37 PMOP *xhv_pmroot; /* list of pm's for this package */
38 char *xhv_name; /* name, if a symbol table */
79072805 39};
40
bf6bd887 41#define PERL_HASH(hash,str,len) \
42 STMT_START { \
08105a92 43 register const char *s_PeRlHaSh = str; \
bf6bd887 44 register I32 i_PeRlHaSh = len; \
45 register U32 hash_PeRlHaSh = 0; \
46 while (i_PeRlHaSh--) \
47 hash_PeRlHaSh = hash_PeRlHaSh * 33 + *s_PeRlHaSh++; \
8ac04967 48 (hash) = hash_PeRlHaSh + (hash_PeRlHaSh>>5); \
bf6bd887 49 } STMT_END
50
954c1994 51/*
52=for apidoc AmU||HEf_SVKEY
53This flag, used in the length slot of hash entries and magic structures,
54specifies the structure contains a C<SV*> pointer where a C<char*> pointer
55is to be expected. (For information only--not to be used).
56
57=for apidoc AmU||Nullhv
58Null HV pointer.
59
60=for apidoc Am|char*|HvNAME|HV* stash
61Returns the package name of a stash. See C<SvSTASH>, C<CvSTASH>.
62
63=for apidoc Am|void*|HeKEY|HE* he
64Returns the actual pointer stored in the key slot of the hash entry. The
65pointer may be either C<char*> or C<SV*>, depending on the value of
66C<HeKLEN()>. Can be assigned to. The C<HePV()> or C<HeSVKEY()> macros are
67usually preferable for finding the value of a key.
68
69=for apidoc Am|STRLEN|HeKLEN|HE* he
70If this is negative, and amounts to C<HEf_SVKEY>, it indicates the entry
71holds an C<SV*> key. Otherwise, holds the actual length of the key. Can
72be assigned to. The C<HePV()> macro is usually preferable for finding key
73lengths.
74
75=for apidoc Am|SV*|HeVAL|HE* he
76Returns the value slot (type C<SV*>) stored in the hash entry.
77
78=for apidoc Am|U32|HeHASH|HE* he
79Returns the computed hash stored in the hash entry.
80
81=for apidoc Am|char*|HePV|HE* he|STRLEN len
82Returns the key slot of the hash entry as a C<char*> value, doing any
83necessary dereferencing of possibly C<SV*> keys. The length of the string
84is placed in C<len> (this is a macro, so do I<not> use C<&len>). If you do
85not care about what the length of the key is, you may use the global
86variable C<PL_na>, though this is rather less efficient than using a local
87variable. Remember though, that hash keys in perl are free to contain
88embedded nulls, so using C<strlen()> or similar is not a good way to find
89the length of hash keys. This is very similar to the C<SvPV()> macro
90described elsewhere in this document.
91
92=for apidoc Am|SV*|HeSVKEY|HE* he
93Returns the key as an C<SV*>, or C<Nullsv> if the hash entry does not
94contain an C<SV*> key.
95
96=for apidoc Am|SV*|HeSVKEY_force|HE* he
97Returns the key as an C<SV*>. Will create and return a temporary mortal
98C<SV*> if the hash entry contains only a C<char*> key.
99
100=for apidoc Am|SV*|HeSVKEY_set|HE* he|SV* sv
101Sets the key to a given C<SV*>, taking care to set the appropriate flags to
102indicate the presence of an C<SV*> key, and returns the same
103C<SV*>.
104
105=cut
106*/
bf6bd887 107
bf5b86ae 108/* these hash entry flags ride on hent_klen (for use only in magic/tied HVs) */
109#define HEf_SVKEY -2 /* hent_key is a SV* */
bf6bd887 110
111
79072805 112#define Nullhv Null(HV*)
463ee0b2 113#define HvARRAY(hv) ((HE**)((XPVHV*) SvANY(hv))->xhv_array)
79072805 114#define HvFILL(hv) ((XPVHV*) SvANY(hv))->xhv_fill
463ee0b2 115#define HvMAX(hv) ((XPVHV*) SvANY(hv))->xhv_max
116#define HvKEYS(hv) ((XPVHV*) SvANY(hv))->xhv_keys
79072805 117#define HvRITER(hv) ((XPVHV*) SvANY(hv))->xhv_riter
118#define HvEITER(hv) ((XPVHV*) SvANY(hv))->xhv_eiter
119#define HvPMROOT(hv) ((XPVHV*) SvANY(hv))->xhv_pmroot
120#define HvNAME(hv) ((XPVHV*) SvANY(hv))->xhv_name
a0d0e21e 121
bf6bd887 122#define HvSHAREKEYS(hv) (SvFLAGS(hv) & SVphv_SHAREKEYS)
123#define HvSHAREKEYS_on(hv) (SvFLAGS(hv) |= SVphv_SHAREKEYS)
124#define HvSHAREKEYS_off(hv) (SvFLAGS(hv) &= ~SVphv_SHAREKEYS)
125
bf5b86ae 126#define HvLAZYDEL(hv) (SvFLAGS(hv) & SVphv_LAZYDEL)
127#define HvLAZYDEL_on(hv) (SvFLAGS(hv) |= SVphv_LAZYDEL)
128#define HvLAZYDEL_off(hv) (SvFLAGS(hv) &= ~SVphv_LAZYDEL)
129
a0d0e21e 130/* Maybe amagical: */
131/* #define HV_AMAGICmb(hv) (SvFLAGS(hv) & (SVpgv_badAM | SVpgv_AM)) */
132
133#define HV_AMAGIC(hv) (SvFLAGS(hv) & SVpgv_AM)
134#define HV_AMAGIC_on(hv) (SvFLAGS(hv) |= SVpgv_AM)
135#define HV_AMAGIC_off(hv) (SvFLAGS(hv) &= ~SVpgv_AM)
136
137/*
138#define HV_AMAGICbad(hv) (SvFLAGS(hv) & SVpgv_badAM)
139#define HV_badAMAGIC_on(hv) (SvFLAGS(hv) |= SVpgv_badAM)
140#define HV_badAMAGIC_off(hv) (SvFLAGS(hv) &= ~SVpgv_badAM)
141*/
bf6bd887 142
143#define Nullhe Null(HE*)
144#define HeNEXT(he) (he)->hent_next
ff68c719 145#define HeKEY_hek(he) (he)->hent_hek
146#define HeKEY(he) HEK_KEY(HeKEY_hek(he))
bbce6d69 147#define HeKEY_sv(he) (*(SV**)HeKEY(he))
ff68c719 148#define HeKLEN(he) HEK_LEN(HeKEY_hek(he))
bf6bd887 149#define HeVAL(he) (he)->hent_val
ff68c719 150#define HeHASH(he) HEK_HASH(HeKEY_hek(he))
1e422769 151#define HePV(he,lp) ((HeKLEN(he) == HEf_SVKEY) ? \
152 SvPV(HeKEY_sv(he),lp) : \
153 (((lp = HeKLEN(he)) >= 0) ? \
154 HeKEY(he) : Nullch))
155
bbce6d69 156#define HeSVKEY(he) ((HeKEY(he) && \
157 HeKLEN(he) == HEf_SVKEY) ? \
158 HeKEY_sv(he) : Nullsv)
159
160#define HeSVKEY_force(he) (HeKEY(he) ? \
161 ((HeKLEN(he) == HEf_SVKEY) ? \
162 HeKEY_sv(he) : \
79cb57f6 163 sv_2mortal(newSVpvn(HeKEY(he), \
bbce6d69 164 HeKLEN(he)))) : \
3280af22 165 &PL_sv_undef)
1e422769 166#define HeSVKEY_set(he,sv) ((HeKLEN(he) = HEf_SVKEY), (HeKEY_sv(he) = sv))
bbce6d69 167
ff68c719 168#define Nullhek Null(HEK*)
71be2cbc 169#define HEK_BASESIZE STRUCT_OFFSET(HEK, hek_key[0])
ff68c719 170#define HEK_HASH(hek) (hek)->hek_hash
171#define HEK_LEN(hek) (hek)->hek_len
172#define HEK_KEY(hek) (hek)->hek_key
d18c6117 173
174#if defined(STRANGE_MALLOC) || defined(MYMALLOC)
175# define PERL_HV_ARRAY_ALLOC_BYTES(size) ((size) * sizeof(HE*))
176#else
177# define MALLOC_OVERHEAD 16
178# define PERL_HV_ARRAY_ALLOC_BYTES(size) \
179 (((size) < 64) \
180 ? (size) * sizeof(HE*) \
181 : (size) * sizeof(HE*) * 2 - MALLOC_OVERHEAD)
182#endif