ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/deliantra/server/common/shstr.C
(Generate patch)

Comparing deliantra/server/common/shstr.C (file contents):
Revision 1.6 by root, Sun Sep 3 11:37:25 2006 UTC vs.
Revision 1.55 by root, Sat Dec 1 20:22:12 2018 UTC

1/*
2 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
3 *
4 * Copyright (©) 2017,2018 Marc Alexander Lehmann / the Deliantra team
5 * Copyright (©) 2005,2006,2007,2008,2009,2010,2011,2012,2013,2014,2015,2016 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
6 *
7 * Deliantra is free software: you can redistribute it and/or modify it under
8 * the terms of the Affero GNU General Public License as published by the
9 * Free Software Foundation, either version 3 of the License, or (at your
10 * option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the Affero GNU General Public License
18 * and the GNU General Public License along with this program. If not, see
19 * <http://www.gnu.org/licenses/>.
20 *
21 * The authors can be reached via e-mail to <support@deliantra.net>
22 */
23
1/* 24/*
2 * shstr.C 25 * shstr.C
3 */ 26 */
4 27
5#include <cstring> 28#include <cstring>
6#include <cstdlib> 29#include <cstdlib>
30#include <glib.h>
7 31
8#include <tr1/unordered_set> 32#include <flat_hash_map.hpp>
9 33
10#include "shstr.h" 34#include <global.h>
11 35
12// NOTE: even with lots of stuff loaded, we do not usually have >>20000 strings. 36size_t shstr_alloc;
13// maybe refcounting is just overhead?
14 37
15struct hash 38typedef ska::flat_hash_set<const char *, str_hash, str_equal, slice_allocator<const char *>> HT;
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 39
52static HT ht; 40static HT ht;
41static int next_gc;
42
43#define NUM_INT 3
44
45static const char *
46makevec (const char *s)
47{
48 int len = strlen (s);
49 int alloc = sizeof (uint32_t) * NUM_INT + len + 1;
50
51 shstr_alloc += alloc;
52 char *v = (char *)g_slice_alloc (alloc);
53 v += sizeof (uint32_t) * NUM_INT;
54
55 shstr::hash (v) = strhsh (s);
56 shstr::length (v) = len;
57 shstr::refcnt (v) = 1;
58
59 memcpy (v, s, len + 1);
60
61 return v;
62}
63
64shstr_vec<sizeof "(null)"> shstr_tmp::nullvec = { STRHSH_NULL, 0, 0xffffffff, "(null)" };
65
66bool
67shstr_tmp::contains (const char *substring) const
68{
69 //TODO: this is supposed to check for comma-seperation...
70 return s != null ()
71 && substring
72 && strstr (s, substring);
73}
53 74
54const char * 75const char *
55shstr::find (const char *s) 76shstr::find (const char *s)
56{ 77{
57 if (!s) 78 if (!s)
58 return s; 79 return s;
59 80
60 HT::iterator i = ht.find (s); 81 auto i = ht.find (s);
61 82
62 return i != ht.end () 83 return i != ht.end ()? *i : 0;
63 ? *i
64 : 0;
65} 84}
66 85
67const char * 86const char *
68shstr::intern (const char *s) 87shstr::intern (const char *s)
69{ 88{
70 if (!s) 89 if (!s)
71 return s; 90 return null ();
72 91
73 if (const char *found = find (s)) 92 if (const char *found = find (s))
74 { 93 {
75 ++refcnt (found); 94 ++refcnt (found);
76 return found; 95 return found;
77 } 96 }
78 97
79 int len = strlen (s); 98 --next_gc;
80 99 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); 100 ht.insert (s);
89
90 return v; 101 return s;
91} 102}
92 103
93// periodically test refcounts == 0 for a few strings 104// periodically test refcounts == 0 for a few strings
94// this is the ONLY thing that erases stuff from ht. keep it that way. 105// this is the ONLY thing that erases stuff from ht. keep it that way.
95void 106void
96shstr::gc () 107shstr::gc ()
97{ 108{
109 if (expect_true (next_gc > 0))
110 return;
111
98 static const char *curpos; 112 static const char *curpos;
99 113
100 HT::iterator i = curpos ? ht.find (curpos) : ht.begin (); 114 auto i = curpos ? ht.find (curpos) : ht.begin ();
101 115
102 if (i == ht.end ()) 116 if (i == ht.end ())
103 i = ht.begin (); 117 i = ht.begin ();
104 118
105 // go through all strings roughly once every 4 minutes
106 int n = ht.size () / 256 + 16; 119 int n = ht.size () / 256 + 16;
120 next_gc += n >> 1;
107 121
108 for (;;) 122 for (;;)
109 { 123 {
110 if (i == ht.end ()) 124 if (i == ht.end ())
111 { 125 {
… …
114 } 128 }
115 else if (!--n) 129 else if (!--n)
116 break; 130 break;
117 else if (!refcnt (*i)) 131 else if (!refcnt (*i))
118 { 132 {
119 HT::iterator o = i++;
120 const char *s = *o; 133 const char *s = *i;
134
121 ht.erase (o); 135 i = ht.erase (i);
122 136
123 //printf ("GC %4d %3d %d >%s<%d\n", (int)ht.size (), n, shstr::refcnt (s), s, shstr::length (s)); 137 //printf ("GC %4d %3d %d >%s<%d\n", (int)ht.size (), n, shstr::refcnt (s), s, shstr::length (s));
124 free (-2 + (int *)s); 138 int alloc = sizeof (uint32_t) * NUM_INT + length (s) + 1;
139 shstr_alloc -= alloc;
140 g_slice_free1 (alloc, (void *)(s - sizeof (uint32_t) * NUM_INT));
125 } 141 }
126 else 142 else
127 ++i; 143 ++i;
128 } 144 }
129 145
130 curpos = *i; 146 curpos = *i;
131} 147}
132 148
133//TODO: this should of course not be here 149// declare these here to get correct initialisation order
134/* buf_overflow() - we don't want to exceed the buffer size of 150#define def2(id,str) const shstr id (str);
135 * buf1 by adding on buf2! Returns true if overflow will occur. 151#define def(id) def2(shstr_ ## id, # id)
136 */ 152# include "shstrinc.h"
153#undef def
154#undef def2
137 155
138int 156materialtype_t material_null;
139buf_overflow (const char *buf1, const char *buf2, int bufsize)
140{
141 int len1 = 0, len2 = 0;
142 157
143 if (buf1) 158struct 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

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines