diff options
Diffstat (limited to 'hv.c')
| -rw-r--r-- | hv.c | 202 |
1 files changed, 201 insertions, 1 deletions
@@ -1,6 +1,6 @@ /* hv.c * - * Copyright (c) 1991-1999, Larry Wall + * Copyright (c) 1991-2000, Larry Wall * * You may distribute under the terms of either the GNU General Public * License or the Artistic License, as specified in the README file. @@ -105,6 +105,20 @@ Perl_he_dup(pTHX_ HE *e, bool shared) /* (klen == HEf_SVKEY) is special for MAGICAL hv entries, meaning key slot * contains an SV* */ +/* +=for apidoc hv_fetch + +Returns the SV which corresponds to the specified key in the hash. The +C<klen> is the length of the key. If C<lval> is set then the fetch will be +part of a store. Check that the return value is non-null before +dereferencing it to a C<SV*>. + +See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more +information on how to use this function on tied hashes. + +=cut +*/ + SV** Perl_hv_fetch(pTHX_ HV *hv, const char *key, U32 klen, I32 lval) { @@ -184,6 +198,23 @@ Perl_hv_fetch(pTHX_ HV *hv, const char *key, U32 klen, I32 lval) /* returns a HE * structure with the all fields set */ /* note that hent_val will be a mortal sv for MAGICAL hashes */ +/* +=for apidoc hv_fetch_ent + +Returns the hash entry which corresponds to the specified key in the hash. +C<hash> must be a valid precomputed hash number for the given C<key>, or 0 +if you want the function to compute it. IF C<lval> is set then the fetch +will be part of a store. Make sure the return value is non-null before +accessing it. The return value when C<tb> is a tied hash is a pointer to a +static location, so be sure to make a copy of the structure if you need to +store it somewhere. + +See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more +information on how to use this function on tied hashes. + +=cut +*/ + HE * Perl_hv_fetch_ent(pTHX_ HV *hv, SV *keysv, I32 lval, register U32 hash) { @@ -293,6 +324,24 @@ S_hv_magic_check(pTHX_ HV *hv, bool *needs_copy, bool *needs_store) } } +/* +=for apidoc hv_store + +Stores an SV in a hash. The hash key is specified as C<key> and C<klen> is +the length of the key. The C<hash> parameter is the precomputed hash +value; if it is zero then Perl will compute it. The return value will be +NULL if the operation failed or if the value did not need to be actually +stored within the hash (as in the case of tied hashes). Otherwise it can +be dereferenced to get the original C<SV*>. Note that the caller is +responsible for suitably incrementing the reference count of C<val> before +the call, and decrementing it if the function returned NULL. + +See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more +information on how to use this function on tied hashes. + +=cut +*/ + SV** Perl_hv_store(pTHX_ HV *hv, const char *key, U32 klen, SV *val, register U32 hash) { @@ -363,6 +412,25 @@ Perl_hv_store(pTHX_ HV *hv, const char *key, U32 klen, SV *val, register U32 has return &HeVAL(entry); } +/* +=for apidoc hv_store_ent + +Stores C<val> in a hash. The hash key is specified as C<key>. The C<hash> +parameter is the precomputed hash value; if it is zero then Perl will +compute it. The return value is the new hash entry so created. It will be +NULL if the operation failed or if the value did not need to be actually +stored within the hash (as in the case of tied hashes). Otherwise the +contents of the return value can be accessed using the C<He???> macros +described here. Note that the caller is responsible for suitably +incrementing the reference count of C<val> before the call, and +decrementing it if the function returned NULL. + +See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more +information on how to use this function on tied hashes. + +=cut +*/ + HE * Perl_hv_store_ent(pTHX_ HV *hv, SV *keysv, SV *val, register U32 hash) { @@ -445,6 +513,17 @@ Perl_hv_store_ent(pTHX_ HV *hv, SV *keysv, SV *val, register U32 hash) return entry; } +/* +=for apidoc hv_delete + +Deletes a key/value pair in the hash. The value SV is removed from the +hash and returned to the caller. The C<klen> is the length of the key. +The C<flags> value will normally be zero; if set to G_DISCARD then NULL +will be returned. + +=cut +*/ + SV * Perl_hv_delete(pTHX_ HV *hv, const char *key, U32 klen, I32 flags) { @@ -516,6 +595,17 @@ Perl_hv_delete(pTHX_ HV *hv, const char *key, U32 klen, I32 flags) return Nullsv; } +/* +=for apidoc hv_delete_ent + +Deletes a key/value pair in the hash. The value SV is removed from the +hash and returned to the caller. The C<flags> value will normally be zero; +if set to G_DISCARD then NULL will be returned. C<hash> can be a valid +precomputed hash value, or 0 to ask for it to be computed. + +=cut +*/ + SV * Perl_hv_delete_ent(pTHX_ HV *hv, SV *keysv, I32 flags, U32 hash) { @@ -592,6 +682,15 @@ Perl_hv_delete_ent(pTHX_ HV *hv, SV *keysv, I32 flags, U32 hash) return Nullsv; } +/* +=for apidoc hv_exists + +Returns a boolean indicating whether the specified hash key exists. The +C<klen> is the length of the key. + +=cut +*/ + bool Perl_hv_exists(pTHX_ HV *hv, const char *key, U32 klen) { @@ -657,6 +756,16 @@ Perl_hv_exists(pTHX_ HV *hv, const char *key, U32 klen) } +/* +=for apidoc hv_exists_ent + +Returns a boolean indicating whether the specified hash key exists. C<hash> +can be a valid precomputed hash value, or 0 to ask for it to be +computed. + +=cut +*/ + bool Perl_hv_exists_ent(pTHX_ HV *hv, SV *keysv, U32 hash) { @@ -867,6 +976,14 @@ Perl_hv_ksplit(pTHX_ HV *hv, IV newmax) } } +/* +=for apidoc newHV + +Creates a new HV. The reference count is set to 1. + +=cut +*/ + HV * Perl_newHV(pTHX) { @@ -967,6 +1084,14 @@ Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry) del_he(entry); } +/* +=for apidoc hv_clear + +Clears a hash, making it empty. + +=cut +*/ + void Perl_hv_clear(pTHX_ HV *hv) { @@ -1017,6 +1142,14 @@ S_hfreeentries(pTHX_ HV *hv) (void)hv_iterinit(hv); } +/* +=for apidoc hv_undef + +Undefines the hash. + +=cut +*/ + void Perl_hv_undef(pTHX_ HV *hv) { @@ -1039,6 +1172,20 @@ Perl_hv_undef(pTHX_ HV *hv) mg_clear((SV*)hv); } +/* +=for apidoc hv_iterinit + +Prepares a starting point to traverse a hash table. Returns the number of +keys in the hash (i.e. the same as C<HvKEYS(tb)>). The return value is +currently only meaningful for hashes without tie magic. + +NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of +hash buckets that happen to be in use. If you still need that esoteric +value, you can get it through the macro C<HvFILL(tb)>. + +=cut +*/ + I32 Perl_hv_iterinit(pTHX_ HV *hv) { @@ -1058,6 +1205,14 @@ Perl_hv_iterinit(pTHX_ HV *hv) return xhv->xhv_keys; /* used to be xhv->xhv_fill before 5.004_65 */ } +/* +=for apidoc hv_iternext + +Returns entries from a hash iterator. See C<hv_iterinit>. + +=cut +*/ + HE * Perl_hv_iternext(pTHX_ HV *hv) { @@ -1129,6 +1284,15 @@ Perl_hv_iternext(pTHX_ HV *hv) return entry; } +/* +=for apidoc hv_iterkey + +Returns the key from the current position of the hash iterator. See +C<hv_iterinit>. + +=cut +*/ + char * Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen) { @@ -1145,6 +1309,16 @@ Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen) } /* unlike hv_iterval(), this always returns a mortal copy of the key */ +/* +=for apidoc hv_iterkeysv + +Returns the key as an C<SV*> from the current position of the hash +iterator. The return value will always be a mortal copy of the key. Also +see C<hv_iterinit>. + +=cut +*/ + SV * Perl_hv_iterkeysv(pTHX_ register HE *entry) { @@ -1155,6 +1329,15 @@ Perl_hv_iterkeysv(pTHX_ register HE *entry) HeKLEN(entry))); } +/* +=for apidoc hv_iterval + +Returns the value from the current position of the hash iterator. See +C<hv_iterkey>. + +=cut +*/ + SV * Perl_hv_iterval(pTHX_ HV *hv, register HE *entry) { @@ -1170,6 +1353,15 @@ Perl_hv_iterval(pTHX_ HV *hv, register HE *entry) return HeVAL(entry); } +/* +=for apidoc hv_iternextsv + +Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one +operation. + +=cut +*/ + SV * Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen) { @@ -1180,6 +1372,14 @@ Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen) return hv_iterval(hv, he); } +/* +=for apidoc hv_magic + +Adds magic to a hash. See C<sv_magic>. + +=cut +*/ + void Perl_hv_magic(pTHX_ HV *hv, GV *gv, int how) { |