server/common/shstr.C

/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 * 
 * Copyright (©) 2005,2006,2007,2008 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
 * 
 * Deliantra 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 3 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, see <http://www.gnu.org/licenses/>.
 * 
 * The authors can be reached via e-mail to <support@deliantra.net>
 */

/*
 * shstr.C
 */

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

#include "global.h"

size_t shstr_alloc;

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

static HT ht;
static int next_gc;

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

  shstr_alloc += sizeof (int) * 2 + len + 1;
  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;
    }

  --next_gc;
  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 ()
{
  if (expect_true (next_gc > 0))
    return;

  static const char *curpos;

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

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

  int n = ht.size () / 256 + 16;
  next_gc += n >> 1;

  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));
          shstr_alloc -= sizeof (int) * 2 + length (s) + 1;
          g_slice_free1 (sizeof (int) * 2 + length (s) + 1, -2 + (int *) s);
        }
      else
        ++i;
    }

  curpos = *i;
}

// declare these here to get correct initialisation order
#define def(str) const shstr shstr_ ## str (# str);
# include "shstrinc.h"
#undef def

shstr skill_names[NUM_SKILLS];

//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:	1.29
Committed:	Fri Apr 11 21:09:52 2008 UTC (16 years, 1 month ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-2_5, rel-2_52
Changes since 1.28:	+7 -1 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	elmex	1.1	/*
2	root	1.28	* This file is part of Deliantra, the Roguelike Realtime MMORPG.
3	root	1.23	*
4	root	1.29	* Copyright (©) 2005,2006,2007,2008 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5	root	1.23	*
6	root	1.28	* Deliantra is free software: you can redistribute it and/or modify
7	root	1.24	* it under the terms of the GNU General Public License as published by
8			* the Free Software Foundation, either version 3 of the License, or
9			* (at your option) any later version.
10	root	1.23	*
11	root	1.24	* 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	root	1.23	*
16	root	1.24	* You should have received a copy of the GNU General Public License
17			* along with this program. If not, see <http://www.gnu.org/licenses/>.
18	root	1.23	*
19	root	1.28	* The authors can be reached via e-mail to <support@deliantra.net>
20	root	1.22	*/
21
22			/*
23	root	1.3	* shstr.C
24	elmex	1.1	*/
25
26	root	1.3	#include <cstring>
27			#include <cstdlib>
28	root	1.10	#include <glib.h>
29	root	1.3	#include <tr1/unordered_set>
30	elmex	1.1
31	root	1.16	#include "global.h"
32	elmex	1.1
33	root	1.26	size_t shstr_alloc;
34
35	root	1.18	typedef std::tr1::unordered_set <const char , str_hash, str_equal, slice_allocator<const char >, true> HT;
36	elmex	1.1
37	root	1.16	static HT ht;
38	root	1.29	static int next_gc;
39	elmex	1.1
40	root	1.13	static const char *
41			makevec (const char *s)
42	root	1.7	{
43	root	1.17	int len = strlen (s);
44	root	1.7
45	root	1.26	shstr_alloc += sizeof (int) * 2 + len + 1;
46	root	1.18	const char v = (const char ) (2 + (int )g_slice_alloc (sizeof (int) 2 + len + 1));
47	root	1.7
48			shstr::length (v) = len;
49			shstr::refcnt (v) = 1;
50
51	root	1.13	memcpy ((char *) v, s, len + 1);
52	root	1.7
53	root	1.8	return v;
54	root	1.7	}
55
56	root	1.17	static const char *
57			makenull ()
58			{
59			const char *s = makevec ("(null)");
60			shstr::length (s) = 0;
61			return s;
62			}
63
64			const char *shstr::null = makenull ();
65	root	1.15
66	elmex	1.1	const char *
67	root	1.3	shstr::find (const char *s)
68			{
69	root	1.4	if (!s)
70			return s;
71
72	root	1.21	auto (i, ht.find (s));
73	elmex	1.1
74	root	1.13	return i != ht.end ()? *i : 0;
75	elmex	1.1	}
76
77			const char *
78	root	1.3	shstr::intern (const char *s)
79			{
80	root	1.4	if (!s)
81	root	1.7	return null;
82	elmex	1.1
83	root	1.4	if (const char *found = find (s))
84	root	1.5	{
85			++refcnt (found);
86			return found;
87			}
88	elmex	1.1
89	root	1.29	--next_gc;
90	root	1.7	s = makevec (s);
91			ht.insert (s);
92			return s;
93	elmex	1.1	}
94
95	root	1.5	// periodically test refcounts == 0 for a few strings
96			// this is the ONLY thing that erases stuff from ht. keep it that way.
97	elmex	1.1	void
98	root	1.3	shstr::gc ()
99			{
100	root	1.29	if (expect_true (next_gc > 0))
101			return;
102
103	root	1.5	static const char *curpos;
104
105	root	1.21	auto (i, curpos ? ht.find (curpos) : ht.begin ());
106	root	1.5
107			if (i == ht.end ())
108			i = ht.begin ();
109
110	root	1.11	int n = ht.size () / 256 + 16;
111	root	1.29	next_gc += n >> 1;
112	root	1.6
113			for (;;)
114	root	1.5	{
115			if (i == ht.end ())
116			{
117			curpos = 0;
118			return;
119			}
120	root	1.6	else if (!--n)
121			break;
122			else if (!refcnt (*i))
123	root	1.5	{
124	root	1.21	auto (o, i++);
125	root	1.5	const char s = o;
126	root	1.13
127	root	1.5	ht.erase (o);
128
129			//printf ("GC %4d %3d %d >%s<%d\n", (int)ht.size (), n, shstr::refcnt (s), s, shstr::length (s));
130	root	1.26	shstr_alloc -= sizeof (int) * 2 + length (s) + 1;
131	root	1.13	g_slice_free1 (sizeof (int) * 2 + length (s) + 1, -2 + (int *) s);
132	root	1.5	}
133			else
134			++i;
135			}
136
137			curpos = *i;
138	elmex	1.1	}
139
140	root	1.25	// declare these here to get correct initialisation order
141			#define def(str) const shstr shstr_ ## str (# str);
142			# include "shstrinc.h"
143			#undef def
144
145	root	1.16	shstr skill_names[NUM_SKILLS];
146
147	root	1.5	//TODO: this should of course not be here
148	root	1.13
149	elmex	1.1	/* buf_overflow() - we don't want to exceed the buffer size of
150			* buf1 by adding on buf2! Returns true if overflow will occur.
151			*/
152	root	1.13	int
153	elmex	1.1	buf_overflow (const char buf1, const char buf2, int bufsize)
154			{
155	root	1.13	int len1 = 0, len2 = 0;
156	elmex	1.1
157	root	1.13	if (buf1)
158			len1 = strlen (buf1);
159	root	1.26
160	root	1.13	if (buf2)
161			len2 = strlen (buf2);
162	root	1.26
163	root	1.13	if ((len1 + len2) >= bufsize)
164			return 1;
165	root	1.22
166	root	1.13	return 0;
167	elmex	1.1	}