server/common/shstr.C

/*
 * CrossFire, A Multiplayer game
 *
 * Copyright (C) 2005, 2006, 2007 Marc Lehmann & Crossfire+ Development Team
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * The authors can be reached via e-mail at <crossfire@schmorp.de>
 */

/*
 * shstr.C
 */

#include <cstring>
#include <cstdlib>
#include <glib.h>
#include <tr1/unordered_set>

#include "global.h"

typedef std::tr1::unordered_set <const char *, str_hash, str_equal, slice_allocator<const char *>, true> HT;

static HT ht;

static const char *
makevec (const char *s)
{
  int len = strlen (s);

  const char *v = (const char *) (2 + (int *)g_slice_alloc (sizeof (int) * 2 + len + 1));

  shstr::length (v) = len;
  shstr::refcnt (v) = 1;

  memcpy ((char *) v, s, len + 1);

  return v;
}

static const char *
makenull ()
{
  const char *s = makevec ("(null)");
  shstr::length (s) = 0;
  return s;
}

const char *shstr::null = makenull ();

const char *
shstr::find (const char *s)
{
  if (!s)
    return s;

  auto (i, ht.find (s));

  return i != ht.end ()? *i : 0;
}

const char *
shstr::intern (const char *s)
{
  if (!s)
    return null;

  if (const char *found = find (s))
    {
      ++refcnt (found);
      return found;
    }

  s = makevec (s);
  ht.insert (s);
  return s;
}

// periodically test refcounts == 0 for a few strings
// this is the ONLY thing that erases stuff from ht. keep it that way.
void
shstr::gc ()
{
  static const char *curpos;

  auto (i, curpos ? ht.find (curpos) : ht.begin ());

  if (i == ht.end ())
    i = ht.begin ();

  // go through all strings roughly once every 4 minutes
  int n = ht.size () / 256 + 16;

  for (;;)
    {
      if (i == ht.end ())
        {
          curpos = 0;
          return;
        }
      else if (!--n)
        break;
      else if (!refcnt (*i))
        {
          auto (o, i++);
          const char *s = *o;

          ht.erase (o);

          //printf ("GC %4d %3d %d >%s<%d\n", (int)ht.size (), n, shstr::refcnt (s), s, shstr::length (s));
          g_slice_free1 (sizeof (int) * 2 + length (s) + 1, -2 + (int *) s);
        }
      else
        ++i;
    }

  curpos = *i;
}

shstr skill_names[NUM_SKILLS];

// what weird misoptimisation is this again?
const shstr undead_name ("undead");

//TODO: this should of course not be here

/* buf_overflow() - we don't want to exceed the buffer size of 
 * buf1 by adding on buf2! Returns true if overflow will occur.
 */
int
buf_overflow (const char *buf1, const char *buf2, int bufsize)
{
  int len1 = 0, len2 = 0;

  if (buf1)
    len1 = strlen (buf1);
  if (buf2)
    len2 = strlen (buf2);
  if ((len1 + len2) >= bufsize)
    return 1;

  return 0;
}
Revision:	1.22
Committed:	Thu May 17 21:32:08 2007 UTC (17 years ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-2_1
Changes since 1.21:	+23 -3 lines
Log Message:	- prepare common/ for head_ => head change - add some copyrights for files where they were missing
#	Content
1	/*
2	* CrossFire, A Multiplayer game
3	*
4	* Copyright (C) 2005, 2006, 2007 Marc Lehmann & Crossfire+ Development Team
5	*
6	* This program is free software; you can redistribute it and/or modify
7	* it under the terms of the GNU General Public License as published by
8	* the Free Software Foundation; either version 2 of the License, or
9	* (at your 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 GNU General Public License
17	* along with this program; if not, write to the Free Software
18	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19	*
20	* The authors can be reached via e-mail at <crossfire@schmorp.de>
21	*/
22
23	/*
24	* shstr.C
25	*/
26
27	#include <cstring>
28	#include <cstdlib>
29	#include <glib.h>
30	#include <tr1/unordered_set>
31
32	#include "global.h"
33
34	typedef std::tr1::unordered_set <const char , str_hash, str_equal, slice_allocator<const char >, true> HT;
35
36	static HT ht;
37
38	static const char *
39	makevec (const char *s)
40	{
41	int len = strlen (s);
42
43	const char v = (const char ) (2 + (int )g_slice_alloc (sizeof (int) 2 + len + 1));
44
45	shstr::length (v) = len;
46	shstr::refcnt (v) = 1;
47
48	memcpy ((char *) v, s, len + 1);
49
50	return v;
51	}
52
53	static const char *
54	makenull ()
55	{
56	const char *s = makevec ("(null)");
57	shstr::length (s) = 0;
58	return s;
59	}
60
61	const char *shstr::null = makenull ();
62
63	const char *
64	shstr::find (const char *s)
65	{
66	if (!s)
67	return s;
68
69	auto (i, ht.find (s));
70
71	return i != ht.end ()? *i : 0;
72	}
73
74	const char *
75	shstr::intern (const char *s)
76	{
77	if (!s)
78	return null;
79
80	if (const char *found = find (s))
81	{
82	++refcnt (found);
83	return found;
84	}
85
86	s = makevec (s);
87	ht.insert (s);
88	return s;
89	}
90
91	// periodically test refcounts == 0 for a few strings
92	// this is the ONLY thing that erases stuff from ht. keep it that way.
93	void
94	shstr::gc ()
95	{
96	static const char *curpos;
97
98	auto (i, curpos ? ht.find (curpos) : ht.begin ());
99
100	if (i == ht.end ())
101	i = ht.begin ();
102
103	// go through all strings roughly once every 4 minutes
104	int n = ht.size () / 256 + 16;
105
106	for (;;)
107	{
108	if (i == ht.end ())
109	{
110	curpos = 0;
111	return;
112	}
113	else if (!--n)
114	break;
115	else if (!refcnt (*i))
116	{
117	auto (o, i++);
118	const char s = o;
119
120	ht.erase (o);
121
122	//printf ("GC %4d %3d %d >%s<%d\n", (int)ht.size (), n, shstr::refcnt (s), s, shstr::length (s));
123	g_slice_free1 (sizeof (int) * 2 + length (s) + 1, -2 + (int *) s);
124	}
125	else
126	++i;
127	}
128
129	curpos = *i;
130	}
131
132	shstr skill_names[NUM_SKILLS];
133
134	// what weird misoptimisation is this again?
135	const shstr undead_name ("undead");
136
137	//TODO: this should of course not be here
138
139	/* buf_overflow() - we don't want to exceed the buffer size of
140	* buf1 by adding on buf2! Returns true if overflow will occur.
141	*/
142	int
143	buf_overflow (const char buf1, const char buf2, int bufsize)
144	{
145	int len1 = 0, len2 = 0;
146
147	if (buf1)
148	len1 = strlen (buf1);
149	if (buf2)
150	len2 = strlen (buf2);
151	if ((len1 + len2) >= bufsize)
152	return 1;
153
154	return 0;
155	}