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Comparing deliantra/server/common/shstr.C (file contents):
Revision 1.6 by root, Sun Sep 3 11:37:25 2006 UTC vs.
Revision 1.51 by root, Fri Nov 18 04:44:13 2016 UTC

1/*
2 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
3 *
4 * Copyright (©) 2005,2006,2007,2008,2009,2010,2011,2012,2013,2014,2015,2016 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>
29#include <glib.h>
30#include <unordered_set>
7 31
8#include <tr1/unordered_set> 32#include "global.h"
9 33
10#include "shstr.h" 34size_t shstr_alloc;
11 35
12// NOTE: even with lots of stuff loaded, we do not usually have >>20000 strings. 36typedef std::unordered_set <const char *, str_hash, str_equal, slice_allocator<const char *> > HT;
13// maybe refcounting is just overhead?
14
15struct hash
16{
17 std::size_t operator ()(const char *s) const
18 {
19 unsigned long hash = 0;
20 unsigned int i = 0;
21
22 /* use the one-at-a-time hash function, which supposedly is
23 * better than the djb2-like one used by perl5.005, but
24 * certainly is better then the bug used here before.
25 * see http://burtleburtle.net/bob/hash/doobs.html
26 */
27 while (*s)
28 {
29 hash += *s++;
30 hash += hash << 10;
31 hash ^= hash >> 6;
32 }
33
34 hash += hash << 3;
35 hash ^= hash >> 11;
36 hash += hash << 15;
37
38 return hash;
39 }
40};
41
42struct equal
43{
44 bool operator ()(const char *a, const char *b) const
45 {
46 return !strcmp (a, b);
47 }
48};
49
50typedef std::tr1::unordered_set<const char *, hash, equal> HT;
51 37
52static HT ht; 38static HT ht;
39static int next_gc;
40
41#define NUM_INT 3
42
43static const char *
44makevec (const char *s)
45{
46 int len = strlen (s);
47 int alloc = sizeof (uint32_t) * NUM_INT + len + 1;
48
49 shstr_alloc += alloc;
50 char *v = (char *)g_slice_alloc (alloc);
51 v += sizeof (uint32_t) * NUM_INT;
52
53 shstr::hash (v) = strhsh (s);
54 shstr::length (v) = len;
55 shstr::refcnt (v) = 1;
56
57 memcpy (v, s, len + 1);
58
59 return v;
60}
61
62shstr_vec<sizeof "(null)"> shstr_tmp::nullvec = { STRHSH_NULL, 0, 0xffffffff, "(null)" };
63
64bool
65shstr_tmp::contains (const char *substring) const
66{
67 //TODO: this is supposed to check for comma-seperation...
68 return s != null ()
69 && substring
70 && strstr (s, substring);
71}
53 72
54const char * 73const char *
55shstr::find (const char *s) 74shstr::find (const char *s)
56{ 75{
57 if (!s) 76 if (!s)
58 return s; 77 return s;
59 78
60 HT::iterator i = ht.find (s); 79 auto (i, ht.find (s));
61 80
62 return i != ht.end () 81 return i != ht.end ()? *i : 0;
63 ? *i
64 : 0;
65} 82}
66 83
67const char * 84const char *
68shstr::intern (const char *s) 85shstr::intern (const char *s)
69{ 86{
70 if (!s) 87 if (!s)
71 return s; 88 return null ();
72 89
73 if (const char *found = find (s)) 90 if (const char *found = find (s))
74 { 91 {
75 ++refcnt (found); 92 ++refcnt (found);
76 return found; 93 return found;
77 } 94 }
78 95
79 int len = strlen (s); 96 --next_gc;
80 97 s = makevec (s);
81 const char *v = (const char *)(2 + (int *)malloc (sizeof (int) * 2 + len + 1));
82
83 length (v) = len;
84 refcnt (v) = 1;
85
86 memcpy ((char *)v, s, len + 1);
87
88 ht.insert (v); 98 ht.insert (s);
89
90 return v; 99 return s;
91} 100}
92 101
93// periodically test refcounts == 0 for a few strings 102// periodically test refcounts == 0 for a few strings
94// this is the ONLY thing that erases stuff from ht. keep it that way. 103// this is the ONLY thing that erases stuff from ht. keep it that way.
95void 104void
96shstr::gc () 105shstr::gc ()
97{ 106{
107 if (expect_true (next_gc > 0))
108 return;
109
98 static const char *curpos; 110 static const char *curpos;
99 111
100 HT::iterator i = curpos ? ht.find (curpos) : ht.begin (); 112 auto (i, curpos ? ht.find (curpos) : ht.begin ());
101 113
102 if (i == ht.end ()) 114 if (i == ht.end ())
103 i = ht.begin (); 115 i = ht.begin ();
104 116
105 // go through all strings roughly once every 4 minutes
106 int n = ht.size () / 256 + 16; 117 int n = ht.size () / 256 + 16;
118 next_gc += n >> 1;
107 119
108 for (;;) 120 for (;;)
109 { 121 {
110 if (i == ht.end ()) 122 if (i == ht.end ())
111 { 123 {
… …
114 } 126 }
115 else if (!--n) 127 else if (!--n)
116 break; 128 break;
117 else if (!refcnt (*i)) 129 else if (!refcnt (*i))
118 { 130 {
119 HT::iterator o = i++; 131 auto (o, i++);
120 const char *s = *o; 132 const char *s = *o;
133
121 ht.erase (o); 134 ht.erase (o);
122 135
123 //printf ("GC %4d %3d %d >%s<%d\n", (int)ht.size (), n, shstr::refcnt (s), s, shstr::length (s)); 136 //printf ("GC %4d %3d %d >%s<%d\n", (int)ht.size (), n, shstr::refcnt (s), s, shstr::length (s));
124 free (-2 + (int *)s); 137 int alloc = sizeof (uint32_t) * NUM_INT + length (s) + 1;
138 shstr_alloc -= alloc;
139 g_slice_free1 (alloc, (void *)(s - sizeof (uint32_t) * NUM_INT));
125 } 140 }
126 else 141 else
127 ++i; 142 ++i;
128 } 143 }
129 144
130 curpos = *i; 145 curpos = *i;
131} 146}
132 147
133//TODO: this should of course not be here 148// declare these here to get correct initialisation order
134/* buf_overflow() - we don't want to exceed the buffer size of 149#define def2(id,str) const shstr id (str);
135 * buf1 by adding on buf2! Returns true if overflow will occur. 150#define def(id) def2(shstr_ ## id, # id)
136 */ 151# include "shstrinc.h"
152#undef def
153#undef def2
137 154
138int 155materialtype_t material_null;
139buf_overflow (const char *buf1, const char *buf2, int bufsize)
140{
141 int len1 = 0, len2 = 0;
142 156
143 if (buf1) 157struct freed_map freed_map;
144 len1 = strlen (buf1);
145 if (buf2)
146 len2 = strlen (buf2);
147 if ((len1 + len2) >= bufsize)
148 return 1;
149 return 0;
150}
151

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