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Comparing deliantra/server/common/shstr.C (file contents):
Revision 1.3 by root, Sun Sep 3 00:18:40 2006 UTC vs.
Revision 1.54 by root, Sun Nov 25 02:17:31 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
12struct hash 36size_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 37
19 /* use the one-at-a-time hash function, which supposedly is 38typedef ska::flat_hash_set<const char *, str_hash, str_equal, slice_allocator<const char *>> HT;
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;
48 39
49static 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}
50 74
51const char * 75const char *
52shstr::find (const char *s) 76shstr::find (const char *s)
53{ 77{
54 HT::iterator i = ht.find (s); 78 if (!s)
79 return s;
55 80
81 auto (i, ht.find (s));
82
56 return i != ht.end () 83 return i != ht.end ()? *i : 0;
57 ? (char *)*i
58 : 0;
59} 84}
60 85
61const char * 86const char *
62shstr::intern (const char *s) 87shstr::intern (const char *s)
63{ 88{
64 HT::iterator i = ht.find (s); 89 if (!s)
90 return null ();
65 91
66 if (i != ht.end ()) 92 if (const char *found = find (s))
67 return (char *)*i; 93 {
94 ++refcnt (found);
95 return found;
96 }
68 97
69 int len = strlen (s); 98 --next_gc;
70 99 s = makevec (s);
71 int *v = (int *)malloc (sizeof (int) * 2 + len + 1);
72
73 v [0] = len;
74 v [1] = 0;
75
76 v += 2;
77
78 memcpy (v, s, len + 1);
79
80 ht.insert ((char *)v); 100 ht.insert (s);
81 101 return s;
82 return (char *)v;
83} 102}
84 103
85// TODO: periodically test refcounts == 0 for a few strings (e.g. one hash bucket, 104// periodically test refcounts == 0 for a few strings
86// exploiting the fatc that iterators stay valid for unordered_set). 105// this is the ONLY thing that erases stuff from ht. keep it that way.
87void 106void
88shstr::gc () 107shstr::gc ()
89{ 108{
109 if (expect_true (next_gc > 0))
110 return;
111
112 static const char *curpos;
113
114 auto i = curpos ? ht.find (curpos) : ht.begin ();
115
116 if (i == ht.end ())
117 i = ht.begin ();
118
119 int n = ht.size () / 256 + 16;
120 next_gc += n >> 1;
121
122 for (;;)
123 {
124 if (i == ht.end ())
125 {
126 curpos = 0;
127 return;
128 }
129 else if (!--n)
130 break;
131 else if (!refcnt (*i))
132 {
133 const char *s = *i;
134
135 i = ht.erase (i);
136
137 //printf ("GC %4d %3d %d >%s<%d\n", (int)ht.size (), n, shstr::refcnt (s), s, shstr::length (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));
141 }
142 else
143 ++i;
144 }
145
146 curpos = *i;
90} 147}
91 148
92/* buf_overflow() - we don't want to exceed the buffer size of 149// declare these here to get correct initialisation order
93 * buf1 by adding on buf2! Returns true if overflow will occur. 150#define def2(id,str) const shstr id (str);
94 */ 151#define def(id) def2(shstr_ ## id, # id)
152# include "shstrinc.h"
153#undef def
154#undef def2
95 155
96int 156materialtype_t material_null;
97buf_overflow (const char *buf1, const char *buf2, int bufsize)
98{
99 int len1 = 0, len2 = 0;
100 157
101 if (buf1) 158struct freed_map freed_map;
102 len1 = strlen (buf1);
103 if (buf2)
104 len2 = strlen (buf2);
105 if ((len1 + len2) >= bufsize)
106 return 1;
107 return 0;
108}
109

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