server/include/dynbuf.h

/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 * 
 * Copyright (©) 2005,2006,2007,2008,2009 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
 * Copyright (©) 2002,2007 Mark Wedel & Crossfire Development Team
 * Copyright (©) 1992,2007 Frank Tore Johansen
 * 
 * Deliantra is free software: you can redistribute it and/or modify it under
 * the terms of the Affero 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 Affero GNU General Public License
 * and 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>
 */

#ifndef DYNBUF_H__
#define DYNBUF_H__

#include <cstring>
#include <cassert>

#include "util.h"
#include "shstr.h"

// this is a "buffer" that can grow fast
// and is still somewhat space-efficient.
// unlike obstacks or other data structures,
// it never moves data around. basically,
// this is a fast strstream without the overhead.

struct dynbuf
{
protected:
  struct chunk
  {
    chunk *next;
    int alloc;
    int size;
    char data[0];
  };

  char *ptr, *end;
  int _size;

  int extend, cextend;
  chunk *first, *last;

  void reserve (int size);
  void init (int initial);  // allocate sinitial chunk
  void free (chunk *&chain); // free chain of chunks
  char *_linearise (int extra = 0);
  void finalise ();

public:
  
  // initial - the size of the initial chunk to be allocated
  // extend  - first incremental step when buffer size exceeded
  dynbuf (int initial = 4096, int extend = 16384)
  : extend (extend)
  {
    init (initial);
  }

  ~dynbuf ()
  {
    free (first);
  }

  // resets the dynbuf, but does not free the first chunk
  // which is either of size "initial" or the size of the last
  // linearise
  void clear ();

  int  size  () const { return _size + (ptr - last->data); }
  bool empty () const { return !size (); }

  void linearise (void *data);
  char *linearise () // does not 0-terminate(!)
  { 
    return first->next ? _linearise () : first->data;
  }

  int room () const { return end - ptr; }

  // make sure we have "size" extra room
  char *force (int size)
  {
    if (expect_false (ptr + size >= end))
      reserve (size);

    return ptr;
  }

  // allocate size bytes and return pointer to them (caller must force())
  char *falloc (int size)
  {
    char *res = ptr;
    ptr += size;
    return res;
  }

  // allocate size bytes and return pointer to them
  char *alloc (int size)
  {
    force (size);
    return falloc (size);
  }

  void fadd (char c) { *ptr++ = c; }
  void fadd (unsigned char c) { fadd (char (c)); }
  void fadd (const void *p, int len)
  {
    memcpy (falloc (len), p, len);
  }

  void add (const void *p, int len)
  {
    force (len);
    fadd (p, len);
  }

  void add (char c)
  {
    alloc (1)[0] = c;
  }

  void add (const char *s)
  {
     add (s, strlen (s));
  }

  void add (shstr_tmp s)
  {
    add (s.s, s.length ());
  }

  // rather inefficient
  void splice (int offset, int olen, const char *s, int slen);
  void splice (int offset, int olen) { splice (offset, olen, "", 0); }

  //TODO
  //void add_destructive (dynbuf &buf);

  dynbuf &operator << (char c) { add (c); return *this; }
  dynbuf &operator << (unsigned char c) { return *this << char (c); }
  dynbuf &operator << (const char *s) { add (s); return *this; }
  dynbuf &operator << (shstr_tmp s) { add (s); return *this; }
  dynbuf &operator << (const std::string &s) { add (s.data(), s.size ()); return *this; }

  operator std::string ();
};

struct dynbuf_text : dynbuf
{
  dynbuf_text (int initial = 4096, int extend = 16384)
  : dynbuf (initial, extend)
  { }

  using dynbuf::add;
  void add (sint32 i);
  void add (sint64 i);

  //TODO: should optimise the case printf "(name %+d)" as it comes up extremely often

  //using dynbuf::operator <<; // doesn't work, sometimes C++ just suxx
  // instead we use an ugly template function
  template<typename T>
  dynbuf_text &operator << (T c) { *(dynbuf *)this << c; return *this; }

  dynbuf_text &operator << (sint16 i) { add (sint32 (i)); return *this; }
  dynbuf_text &operator << (uint16 i) { add (sint32 (i)); return *this; }
  dynbuf_text &operator << (sint32 i) { add (sint32 (i)); return *this; }
  dynbuf_text &operator << (sint64 i) { add (sint64 (i)); return *this; }
  dynbuf_text &operator << (uint32 i) { add (sint64 (i)); return *this; }
  dynbuf_text &operator << (uint64 i) { add (sint64 (i)); return *this; }

  void printf (const char *format, ...) attribute ((format (printf, 2, 3)));
  void vprintf (const char *format, va_list ap);

  void add_abilities (const char *name, uint32 abilities);
  void add_paths     (const char *name, uint32 paths);

  // we need to redefine, to keep the API :/
  using dynbuf::splice;
  void splice (int offset, int olen, const char *s)
  {
    dynbuf::splice (offset, olen, s, strlen (s));
  }

  // returns the string, linearised and with trailing \0
  operator char *();
};

#endif

Revision:	1.27
Committed:	Sat Nov 7 18:30:05 2009 UTC (14 years, 6 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.26:	+1 -1 lines
Log Message:	lots of cleanups
#	Content
1	/*
2	* This file is part of Deliantra, the Roguelike Realtime MMORPG.
3	*
4	* Copyright (©) 2005,2006,2007,2008,2009 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5	* Copyright (©) 2002,2007 Mark Wedel & Crossfire Development Team
6	* Copyright (©) 1992,2007 Frank Tore Johansen
7	*
8	* Deliantra is free software: you can redistribute it and/or modify it under
9	* the terms of the Affero GNU General Public License as published by the
10	* Free Software Foundation, either version 3 of the License, or (at your
11	* option) any later version.
12	*
13	* This program is distributed in the hope that it will be useful,
14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16	* GNU General Public License for more details.
17	*
18	* You should have received a copy of the Affero GNU General Public License
19	* and the GNU General Public License along with this program. If not, see
20	* <http://www.gnu.org/licenses/>.
21	*
22	* The authors can be reached via e-mail to <support@deliantra.net>
23	*/
24
25	#ifndef DYNBUF_H__
26	#define DYNBUF_H__
27
28	#include <cstring>
29	#include <cassert>
30
31	#include "util.h"
32	#include "shstr.h"
33
34	// this is a "buffer" that can grow fast
35	// and is still somewhat space-efficient.
36	// unlike obstacks or other data structures,
37	// it never moves data around. basically,
38	// this is a fast strstream without the overhead.
39
40	struct dynbuf
41	{
42	protected:
43	struct chunk
44	{
45	chunk *next;
46	int alloc;
47	int size;
48	char data[0];
49	};
50
51	char ptr, end;
52	int _size;
53
54	int extend, cextend;
55	chunk first, last;
56
57	void reserve (int size);
58	void init (int initial); // allocate sinitial chunk
59	void free (chunk *&chain); // free chain of chunks
60	char *_linearise (int extra = 0);
61	void finalise ();
62
63	public:
64
65	// initial - the size of the initial chunk to be allocated
66	// extend - first incremental step when buffer size exceeded
67	dynbuf (int initial = 4096, int extend = 16384)
68	: extend (extend)
69	{
70	init (initial);
71	}
72
73	~dynbuf ()
74	{
75	free (first);
76	}
77
78	// resets the dynbuf, but does not free the first chunk
79	// which is either of size "initial" or the size of the last
80	// linearise
81	void clear ();
82
83	int size () const { return _size + (ptr - last->data); }
84	bool empty () const { return !size (); }
85
86	void linearise (void *data);
87	char *linearise () // does not 0-terminate(!)
88	{
89	return first->next ? _linearise () : first->data;
90	}
91
92	int room () const { return end - ptr; }
93
94	// make sure we have "size" extra room
95	char *force (int size)
96	{
97	if (expect_false (ptr + size >= end))
98	reserve (size);
99
100	return ptr;
101	}
102
103	// allocate size bytes and return pointer to them (caller must force())
104	char *falloc (int size)
105	{
106	char *res = ptr;
107	ptr += size;
108	return res;
109	}
110
111	// allocate size bytes and return pointer to them
112	char *alloc (int size)
113	{
114	force (size);
115	return falloc (size);
116	}
117
118	void fadd (char c) { *ptr++ = c; }
119	void fadd (unsigned char c) { fadd (char (c)); }
120	void fadd (const void *p, int len)
121	{
122	memcpy (falloc (len), p, len);
123	}
124
125	void add (const void *p, int len)
126	{
127	force (len);
128	fadd (p, len);
129	}
130
131	void add (char c)
132	{
133	alloc (1)[0] = c;
134	}
135
136	void add (const char *s)
137	{
138	add (s, strlen (s));
139	}
140
141	void add (shstr_tmp s)
142	{
143	add (s.s, s.length ());
144	}
145
146	// rather inefficient
147	void splice (int offset, int olen, const char *s, int slen);
148	void splice (int offset, int olen) { splice (offset, olen, "", 0); }
149
150	//TODO
151	//void add_destructive (dynbuf &buf);
152
153	dynbuf &operator << (char c) { add (c); return *this; }
154	dynbuf &operator << (unsigned char c) { return *this << char (c); }
155	dynbuf &operator << (const char s) { add (s); return this; }
156	dynbuf &operator << (shstr_tmp s) { add (s); return *this; }
157	dynbuf &operator << (const std::string &s) { add (s.data(), s.size ()); return *this; }
158
159	operator std::string ();
160	};
161
162	struct dynbuf_text : dynbuf
163	{
164	dynbuf_text (int initial = 4096, int extend = 16384)
165	: dynbuf (initial, extend)
166	{ }
167
168	using dynbuf::add;
169	void add (sint32 i);
170	void add (sint64 i);
171
172	//TODO: should optimise the case printf "(name %+d)" as it comes up extremely often
173
174	//using dynbuf::operator <<; // doesn't work, sometimes C++ just suxx
175	// instead we use an ugly template function
176	template<typename T>
177	dynbuf_text &operator << (T c) { (dynbuf )this << c; return *this; }
178
179	dynbuf_text &operator << (sint16 i) { add (sint32 (i)); return *this; }
180	dynbuf_text &operator << (uint16 i) { add (sint32 (i)); return *this; }
181	dynbuf_text &operator << (sint32 i) { add (sint32 (i)); return *this; }
182	dynbuf_text &operator << (sint64 i) { add (sint64 (i)); return *this; }
183	dynbuf_text &operator << (uint32 i) { add (sint64 (i)); return *this; }
184	dynbuf_text &operator << (uint64 i) { add (sint64 (i)); return *this; }
185
186	void printf (const char *format, ...) attribute ((format (printf, 2, 3)));
187	void vprintf (const char *format, va_list ap);
188
189	void add_abilities (const char *name, uint32 abilities);
190	void add_paths (const char *name, uint32 paths);
191
192	// we need to redefine, to keep the API :/
193	using dynbuf::splice;
194	void splice (int offset, int olen, const char *s)
195	{
196	dynbuf::splice (offset, olen, s, strlen (s));
197	}
198
199	// returns the string, linearised and with trailing \0
200	operator char *();
201	};
202
203	#endif
204