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Comparing deliantra/server/common/shstr.C (file contents):
Revision 1.7 by root, Sun Sep 3 23:33:00 2006 UTC vs.
Revision 1.42 by root, Tue Nov 10 04:38:45 2009 UTC

1/*
2 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
3 *
4 * Copyright (©) 2005,2006,2007,2008 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5 *
6 * Deliantra is free software: you can redistribute it and/or modify it under
7 * the terms of the Affero GNU General Public License as published by the
8 * Free Software Foundation, either version 3 of the License, or (at your
9 * option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the Affero GNU General Public License
17 * and the GNU General Public License along with this program. If not, see
18 * <http://www.gnu.org/licenses/>.
19 *
20 * The authors can be reached via e-mail to <support@deliantra.net>
21 */
22
1/* 23/*
2 * shstr.C 24 * shstr.C
3 */ 25 */
4 26
5#include <cstring> 27#include <cstring>
6#include <cstdlib> 28#include <cstdlib>
7 29#include <glib.h>
8#include <tr1/unordered_set> 30#include <tr1/unordered_set>
9 31
10#include "shstr.h" 32#include "global.h"
11 33
12struct hash 34size_t shstr_alloc;
13{
14 std::size_t operator ()(const char *s) const
15 {
16 unsigned long hash = 0;
17 unsigned int i = 0;
18 35
19 /* use the one-at-a-time hash function, which supposedly is
20 * better than the djb2-like one used by perl5.005, but
21 * certainly is better then the bug used here before.
22 * see http://burtleburtle.net/bob/hash/doobs.html
23 */
24 while (*s)
25 {
26 hash += *s++;
27 hash += hash << 10;
28 hash ^= hash >> 6;
29 }
30
31 hash += hash << 3;
32 hash ^= hash >> 11;
33 hash += hash << 15;
34
35 return hash;
36 }
37};
38
39struct equal
40{
41 bool operator ()(const char *a, const char *b) const
42 {
43 return !strcmp (a, b);
44 }
45};
46
47typedef std::tr1::unordered_set<const char *, hash, equal> HT; 36typedef std::tr1::unordered_set <const char *, str_hash, str_equal, slice_allocator<const char *> > HT;
48 37
49static HT ht; 38static HT ht;
39static int next_gc;
50 40
51static const char *makevec (const char *s) 41#define NUM_INT 3
42
43static const char *
44makevec (const char *s)
52{ 45{
53 int len = strlen (s); 46 int len = strlen (s);
47 int alloc = sizeof (uint32_t) * NUM_INT + len + 1;
54 48
55 const char *v = (const char *)(2 + (int *)malloc (sizeof (int) * 2 + len + 1)); 49 shstr_alloc += alloc;
50 char *v = (char *)g_slice_alloc (alloc);
51 v += sizeof (uint32_t) * NUM_INT;
56 52
53 shstr::hash (v) = strhsh (s);
57 shstr::length (v) = len; 54 shstr::length (v) = len;
58 shstr::refcnt (v) = 1; 55 shstr::refcnt (v) = 1;
59 56
60 memcpy ((char *)v, s, len + 1); 57 memcpy (v, s, len + 1);
61 58
62 return s; 59 return v;
63} 60}
64 61
65const char *shstr::null = makevec ("<nil>"); 62shstr_vec<sizeof "(null)"> shstr_tmp::nullvec = { STRHSH_NULL, 0, 0xffffffff, "(null)" };
66 63
67const char * 64const char *
68shstr::find (const char *s) 65shstr::find (const char *s)
69{ 66{
70 if (!s) 67 if (!s)
71 return s; 68 return s;
72 69
73 HT::iterator i = ht.find (s); 70 auto (i, ht.find (s));
74 71
75 return i != ht.end () 72 return i != ht.end ()? *i : 0;
76 ? *i
77 : 0;
78} 73}
79 74
80const char * 75const char *
81shstr::intern (const char *s) 76shstr::intern (const char *s)
82{ 77{
83 if (!s) 78 if (!s)
84 return null; 79 return null ();
85 80
86 if (const char *found = find (s)) 81 if (const char *found = find (s))
87 { 82 {
88 ++refcnt (found); 83 ++refcnt (found);
89 return found; 84 return found;
90 } 85 }
91 86
87 --next_gc;
92 s = makevec (s); 88 s = makevec (s);
93 ht.insert (s); 89 ht.insert (s);
94 return s; 90 return s;
95} 91}
96 92
97// periodically test refcounts == 0 for a few strings 93// periodically test refcounts == 0 for a few strings
98// this is the ONLY thing that erases stuff from ht. keep it that way. 94// this is the ONLY thing that erases stuff from ht. keep it that way.
99void 95void
100shstr::gc () 96shstr::gc ()
101{ 97{
98 if (expect_true (next_gc > 0))
99 return;
100
102 static const char *curpos; 101 static const char *curpos;
103 102
104 HT::iterator i = curpos ? ht.find (curpos) : ht.begin (); 103 auto (i, curpos ? ht.find (curpos) : ht.begin ());
105 104
106 if (i == ht.end ()) 105 if (i == ht.end ())
107 i = ht.begin (); 106 i = ht.begin ();
108 107
109 // go through all strings roughly once every 4 minutes
110 int n = ht.size () / 256 + 16; 108 int n = ht.size () / 256 + 16;
109 next_gc += n >> 1;
111 110
112 for (;;) 111 for (;;)
113 { 112 {
114 if (i == ht.end ()) 113 if (i == ht.end ())
115 { 114 {
… …
118 } 117 }
119 else if (!--n) 118 else if (!--n)
120 break; 119 break;
121 else if (!refcnt (*i)) 120 else if (!refcnt (*i))
122 { 121 {
123 HT::iterator o = i++; 122 auto (o, i++);
124 const char *s = *o; 123 const char *s = *o;
124
125 ht.erase (o); 125 ht.erase (o);
126 126
127 //printf ("GC %4d %3d %d >%s<%d\n", (int)ht.size (), n, shstr::refcnt (s), s, shstr::length (s)); 127 //printf ("GC %4d %3d %d >%s<%d\n", (int)ht.size (), n, shstr::refcnt (s), s, shstr::length (s));
128 free (-2 + (int *)s); 128 int alloc = sizeof (uint32_t) * NUM_INT + length (s) + 1;
129 shstr_alloc -= alloc;
130 g_slice_free1 (alloc, (void *)(s - sizeof (uint32_t) * NUM_INT));
129 } 131 }
130 else 132 else
131 ++i; 133 ++i;
132 } 134 }
133 135
134 curpos = *i; 136 curpos = *i;
135} 137}
136 138
137//TODO: this should of course not be here 139// declare these here to get correct initialisation order
138/* buf_overflow() - we don't want to exceed the buffer size of 140#define def2(id,str) const shstr id (str);
139 * buf1 by adding on buf2! Returns true if overflow will occur. 141#define def(id) def2(shstr_ ## id, # id)
140 */ 142# include "shstrinc.h"
143#undef def
144#undef def2
141 145
142int 146shstr skill_names[NUM_SKILLS];
143buf_overflow (const char *buf1, const char *buf2, int bufsize) 147materialtype_t material_null;
144{
145 int len1 = 0, len2 = 0;
146 148
147 if (buf1)
148 len1 = strlen (buf1);
149 if (buf2)
150 len2 = strlen (buf2);
151 if ((len1 + len2) >= bufsize)
152 return 1;
153 return 0;
154}
155

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