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1#ifndef __OOUC_HASH__
2#define __OOUC_HASH__
4/* */
5/* X r d O u c H a s h . h h */
6/* */
7/* (c) 2004 by the Board of Trustees of the Leland Stanford, Jr., University */
8/* Produced by Andrew Hanushevsky for Stanford University under contract */
9/* DE-AC02-76-SFO0515 with the Department of Energy */
10/* */
11/* This file is part of the XRootD software suite. */
12/* */
13/* XRootD is free software: you can redistribute it and/or modify it under */
14/* the terms of the GNU Lesser General Public License as published by the */
15/* Free Software Foundation, either version 3 of the License, or (at your */
16/* option) any later version. */
17/* */
18/* XRootD is distributed in the hope that it will be useful, but WITHOUT */
19/* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or */
20/* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public */
21/* License for more details. */
22/* */
23/* You should have received a copy of the GNU Lesser General Public License */
24/* along with XRootD in a file called COPYING.LESSER (LGPL license) and file */
25/* COPYING (GPL license). If not, see <http://www.gnu.org/licenses/>. */
26/* */
27/* The copyright holder's institutional names and contributor's names may not */
28/* be used to endorse or promote products derived from this software without */
29/* specific prior written permission of the institution or contributor. */
32#include <cstdlib>
33#include <sys/types.h>
34#include <cstring>
35#include <ctime>
38Hash_data_is_key - The key and data are the same so when an item is added
39 the data pointer is set to the key address.
40Hash_replace - When adding an item, any existing item is replaced.
41Hash_count - The number of deletion requests must equal the number of
42 additions before the item is actually deleted.
43Hash_keep - When the item is added, the key is not duplicated and
44 when the item is deleted, the key *and* data are not deleted.
45Hash_dofree - When an item is deleted the data is released using free()
46 instead of delete().
47Hash_keepdata - Works like Hash_keep but only applies to the data object.
48 When adding the entry, the key is strdup'd and when deleting
49 an entry, the key is freed.
53 Hash_replace = 0x0002,
54 Hash_count = 0x0004,
55 Hash_keep = 0x0008,
56 Hash_dofree = 0x0010,
57 Hash_keepdata = 0x0020
58 };
60template<class T>
64int Count() {return keycount;}
66T *Data() {return keydata;}
68 unsigned long Hash() {return keyhash;}
70const char *Key() {return keyval;}
74time_t Time() {return keytime;}
76void Update(int newcount, time_t newtime)
77 {keycount = newcount;
78 if (newtime) keytime = newtime;
79 }
81int Same(const unsigned long KeyHash, const char *KeyVal)
82 {return keyhash == KeyHash && !strcmp(keyval, KeyVal);}
84void SetNext(XrdOucHash_Item<T> *item) {next = item;}
86 XrdOucHash_Item(unsigned long KeyHash,
87 const char *KeyVal,
88 T *KeyData,
89 time_t KeyTime,
90 XrdOucHash_Item<T> *KeyNext,
91 XrdOucHash_Options KeyOpts)
92 {keyhash = KeyHash;
93 if (KeyOpts & Hash_keep) keyval = KeyVal;
94 else keyval = strdup(KeyVal);
95 if (KeyOpts & Hash_data_is_key) keydata = (T *)keyval;
96 else keydata = KeyData;
97 keytime = KeyTime;
98 entopts = KeyOpts;
99 next = KeyNext;
100 keycount= 0;
101 }
104 {if (!(entopts & Hash_keep))
105 {if (keydata && keydata != (T *)keyval
106 && !(entopts & Hash_keepdata))
107 {if (entopts & Hash_dofree) free(keydata);
108 else delete keydata;
109 }
110 if (keyval) free((void *)keyval);
111 }
112 keydata = 0; keyval = 0; keycount = 0;
113 }
118const char *keyval;
119unsigned long keyhash;
121time_t keytime;
126template<class T>
131// Add() adds a new item to the hash. If it exists and repl = 0 then the old
132// entry is returned and the new data is not added. Otherwise the current
133// entry is replaced (see Rep()) and 0 is returned. If we have no memory
134// to add the new entry, an ENOMEM exception is thrown. The
135// LifeTime value is the number of seconds this entry is to be considered
136// valid. When the time has passed, the entry may be deleted. A value
137// of zero, keeps the entry until explicitly deleted. A special feature
138// allows the data to be associated with the key to be the actual key
139// using the Hash_data_is_key option. In this case, KeyData is ignored.
140// The Hash_count option keeps track of duplicate key entries for Del.
142T *Add(const char *KeyVal, T *KeyData, const int LifeTime=0,
145// Del() deletes the item from the hash. If it doesn't exist, it returns
146// -ENOENT. Otherwise 0 is returned. If the Hash_count option is specified
147// tyhen the entry is only deleted when the entry count is below 0.
149int Del(const char *KeyVal, XrdOucHash_Options opt = Hash_default);
151// Find() simply looks up an entry in the cache. It can optionally return the
152// lifetime associated with the entry. If the
154T *Find(const char *KeyVal, time_t *KeyTime=0);
156// Num() returns the number of items in the hash table
158int Num() {return hashnum;}
160// Purge() simply deletes all of the appendages to the table.
162void Purge();
164// Rep() is simply Add() that allows replacement.
166T *Rep(const char *KeyVal, T *KeyData, const int LifeTime=0,
168 {return Add(KeyVal, KeyData, LifeTime,
171// Apply() applies the specified function to every item in the hash. The
172// first argument is the key value, the second is the associated data,
173// the third argument is whatever is the passed in void *variable, The
174// following actions occur for values returned by the applied function:
175// <0 - The hash table item is deleted.
176// =0 - The next hash table item is processed.
177// >0 - Processing stops and the hash table item is returned.
179T *Apply(int (*func)(const char *, T *, void *), void *Arg);
181// When allocateing a new hash, specify the required starting size. Make
182// sure that the previous number is the correct Fibonocci antecedent. The
183// series is simply n[j] = n[j-1] + n[j-2].
185 XrdOucHash(int psize = 89, int size=144, int load=80);
189void Remove(int kent, XrdOucHash_Item<T> *hip, XrdOucHash_Item<T> *phip);
192 const unsigned long khash,
193 const char *kval,
194 XrdOucHash_Item<T> **phip=0);
196unsigned long HashVal(const char *KeyVal);
198void Expand();
209/* A c t u a l I m p l e m e n t a t i o n */
212#include "XrdOuc/XrdOucHash.icc"
Definition XrdOucHash.hh:51
@ Hash_count
Definition XrdOucHash.hh:54
@ Hash_data_is_key
Definition XrdOucHash.hh:52
@ Hash_keepdata
Definition XrdOucHash.hh:57
@ Hash_default
Definition XrdOucHash.hh:51
@ Hash_replace
Definition XrdOucHash.hh:53
@ Hash_keep
Definition XrdOucHash.hh:55
@ Hash_dofree
Definition XrdOucHash.hh:56
Definition XrdOucHash.hh:62
unsigned long Hash()
Definition XrdOucHash.hh:68
XrdOucHash_Item(unsigned long KeyHash, const char *KeyVal, T *KeyData, time_t KeyTime, XrdOucHash_Item< T > *KeyNext, XrdOucHash_Options KeyOpts)
Definition XrdOucHash.hh:86
int Same(const unsigned long KeyHash, const char *KeyVal)
Definition XrdOucHash.hh:81
XrdOucHash_Item< T > * Next()
Definition XrdOucHash.hh:72
XrdOucHash_Options entopts
Definition XrdOucHash.hh:123
Definition XrdOucHash.hh:103
T * Data()
Definition XrdOucHash.hh:66
void Update(int newcount, time_t newtime)
Definition XrdOucHash.hh:76
time_t Time()
Definition XrdOucHash.hh:74
int Count()
Definition XrdOucHash.hh:64
T * keydata
Definition XrdOucHash.hh:120
XrdOucHash_Item< T > * next
Definition XrdOucHash.hh:117
time_t keytime
Definition XrdOucHash.hh:121
const char * Key()
Definition XrdOucHash.hh:70
int keycount
Definition XrdOucHash.hh:122
unsigned long keyhash
Definition XrdOucHash.hh:119
void SetNext(XrdOucHash_Item< T > *item)
Definition XrdOucHash.hh:84
const char * keyval
Definition XrdOucHash.hh:118
Definition XrdOucHash.hh:128
int Del(const char *KeyVal, XrdOucHash_Options opt=Hash_default)
void Purge()
Definition XrdOucHash.hh:186
unsigned long HashVal(const char *KeyVal)
int hashtablesize
Definition XrdOucHash.hh:202
T * Rep(const char *KeyVal, T *KeyData, const int LifeTime=0, XrdOucHash_Options opt=Hash_default)
Definition XrdOucHash.hh:166
void Expand()
XrdOucHash_Item< T > * Search(XrdOucHash_Item< T > *hip, const unsigned long khash, const char *kval, XrdOucHash_Item< T > **phip=0)
T * Apply(int(*func)(const char *, T *, void *), void *Arg)
void Remove(int kent, XrdOucHash_Item< T > *hip, XrdOucHash_Item< T > *phip)
int hashload
Definition XrdOucHash.hh:205
int hashnum
Definition XrdOucHash.hh:203
int prevtablesize
Definition XrdOucHash.hh:201
int Num()
Definition XrdOucHash.hh:158
T * Add(const char *KeyVal, T *KeyData, const int LifeTime=0, XrdOucHash_Options opt=Hash_default)
T * Find(const char *KeyVal, time_t *KeyTime=0)
XrdOucHash(int psize=89, int size=144, int load=80)
int hashmax
Definition XrdOucHash.hh:204
XrdOucHash_Item< T > ** hashtable
Definition XrdOucHash.hh:200