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Comparing deliantra/server/common/shstr.C (file contents):
Revision 1.4 by root, Sun Sep 3 08:05:39 2006 UTC vs.
Revision 1.18 by root, Tue Sep 12 20:55:40 2006 UTC

1
1/* 2/*
2 * shstr.C 3 * shstr.C
3 */ 4 */
4 5
5#include <cstring> 6#include <cstring>
6#include <cstdlib> 7#include <cstdlib>
7 8
9#include <glib.h>
10
8#include <tr1/unordered_set> 11#include <tr1/unordered_set>
9 12
10#include "shstr.h" 13#include "global.h"
11 14
12struct hash 15typedef std::tr1::unordered_set <const char *, str_hash, str_equal, slice_allocator<const char *>, true> HT;
13{
14 std::size_t operator ()(const char *s) const
15 {
16 unsigned long hash = 0;
17 unsigned int i = 0;
18
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;
48 16
49static HT ht; 17static HT ht;
18
19static const char *
20makevec (const char *s)
21{
22 int len = strlen (s);
23
24 const char *v = (const char *) (2 + (int *)g_slice_alloc (sizeof (int) * 2 + len + 1));
25
26 shstr::length (v) = len;
27 shstr::refcnt (v) = 1;
28
29 memcpy ((char *) v, s, len + 1);
30
31 return v;
32}
33
34static const char *
35makenull ()
36{
37 const char *s = makevec ("(null)");
38 shstr::length (s) = 0;
39 return s;
40}
41
42const char *shstr::null = makenull ();
50 43
51const char * 44const char *
52shstr::find (const char *s) 45shstr::find (const char *s)
53{ 46{
54 if (!s) 47 if (!s)
55 return s; 48 return s;
56 49
57 HT::iterator i = ht.find (s); 50 HT::iterator i = ht.find (s);
58 51
59 return i != ht.end () 52 return i != ht.end ()? *i : 0;
60 ? (char *)*i
61 : 0;
62} 53}
63 54
64const char * 55const char *
65shstr::intern (const char *s) 56shstr::intern (const char *s)
66{ 57{
67 if (!s) 58 if (!s)
68 return s; 59 return null;
69 60
70 if (const char *found = find (s)) 61 if (const char *found = find (s))
62 {
63 ++refcnt (found);
71 return found; 64 return found;
65 }
72 66
73 int len = strlen (s); 67 s = makevec (s);
74
75 int *v = (int *)malloc (sizeof (int) * 2 + len + 1);
76
77 v [0] = len;
78 v [1] = 0;
79
80 v += 2;
81
82 memcpy (v, s, len + 1);
83
84 ht.insert ((char *)v); 68 ht.insert (s);
85 69 return s;
86 return (char *)v;
87} 70}
88 71
89// TODO: periodically test refcounts == 0 for a few strings (e.g. one hash bucket, 72// periodically test refcounts == 0 for a few strings
90// exploiting the fatc that iterators stay valid for unordered_set). 73// this is the ONLY thing that erases stuff from ht. keep it that way.
91void 74void
92shstr::gc () 75shstr::gc ()
93{ 76{
77return; //D
78//D currently disabled: some datastructures might still store them
79//D but their pointers will become invalidated
80 static const char *curpos;
81
82 HT::iterator i = curpos ? ht.find (curpos) : ht.begin ();
83
84 if (i == ht.end ())
85 i = ht.begin ();
86
87 // go through all strings roughly once every 4 minutes
88 int n = ht.size () / 256 + 16;
89
90 for (;;)
91 {
92 if (i == ht.end ())
93 {
94 curpos = 0;
95 return;
96 }
97 else if (!--n)
98 break;
99 else if (!refcnt (*i))
100 {
101 HT::iterator o = i++;
102 const char *s = *o;
103
104 ht.erase (o);
105
106 //printf ("GC %4d %3d %d >%s<%d\n", (int)ht.size (), n, shstr::refcnt (s), s, shstr::length (s));
107 g_slice_free1 (sizeof (int) * 2 + length (s) + 1, -2 + (int *) s);
108 }
109 else
110 ++i;
111 }
112
113 curpos = *i;
94} 114}
115
116shstr skill_names[NUM_SKILLS];
117
118// what weird misoptimisation is this again?
119const shstr undead_name ("undead");
120
121//TODO: this should of course not be here
95 122
96/* buf_overflow() - we don't want to exceed the buffer size of 123/* buf_overflow() - we don't want to exceed the buffer size of
97 * buf1 by adding on buf2! Returns true if overflow will occur. 124 * buf1 by adding on buf2! Returns true if overflow will occur.
98 */ 125 */
99 126
100int 127int
101buf_overflow (const char *buf1, const char *buf2, int bufsize) 128buf_overflow (const char *buf1, const char *buf2, int bufsize)
102{ 129{
103 int len1 = 0, len2 = 0; 130 int len1 = 0, len2 = 0;
104 131
105 if (buf1) 132 if (buf1)
106 len1 = strlen (buf1); 133 len1 = strlen (buf1);
107 if (buf2) 134 if (buf2)
108 len2 = strlen (buf2); 135 len2 = strlen (buf2);
109 if ((len1 + len2) >= bufsize) 136 if ((len1 + len2) >= bufsize)
110 return 1;
111 return 0; 137 return 1;
138 return 0;
112} 139}
113

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