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
#	User	Rev	Content
1	root	1.11	/*
2	root	1.15	* This file is part of Deliantra, the Roguelike Realtime MMORPG.
3	root	1.11	*
4	root	1.25	* Copyright (©) 2005,2006,2007,2008,2009 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5	root	1.11	* Copyright (©) 2002,2007 Mark Wedel & Crossfire Development Team
6			* Copyright (©) 1992,2007 Frank Tore Johansen
7			*
8	root	1.22	* 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	root	1.11	*
13	root	1.12	* 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	root	1.11	*
18	root	1.22	* 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	root	1.11	*
22	root	1.15	* The authors can be reached via e-mail to <support@deliantra.net>
23	root	1.11	*/
24
25	root	1.1	#ifndef DYNBUF_H__
26			#define DYNBUF_H__
27
28			#include <cstring>
29			#include <cassert>
30
31	root	1.8	#include "util.h"
32	root	1.4	#include "shstr.h"
33
34	root	1.1	// 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	root	1.4	struct dynbuf
41	root	1.1	{
42	root	1.4	protected:
43	root	1.1	struct chunk
44			{
45			chunk *next;
46	root	1.5	int alloc;
47	root	1.1	int size;
48			char data[0];
49			};
50
51	root	1.6	char ptr, end;
52	root	1.1	int _size;
53
54	root	1.19	int extend, cextend;
55	root	1.1	chunk first, last;
56
57	root	1.13	void reserve (int size);
58			void init (int initial); // allocate sinitial chunk
59			void free (chunk *&chain); // free chain of chunks
60	root	1.26	char *_linearise (int extra = 0);
61	root	1.13	void finalise ();
62	root	1.1
63			public:
64
65	root	1.13	// 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	root	1.1
83	root	1.6	int size () const { return _size + (ptr - last->data); }
84			bool empty () const { return !size (); }
85	root	1.1
86			void linearise (void *data);
87	root	1.13	char *linearise () // does not 0-terminate(!)
88			{
89			return first->next ? _linearise () : first->data;
90			}
91	root	1.6
92			int room () const { return end - ptr; }
93	root	1.1
94	root	1.26	// make sure we have "size" extra room
95	root	1.1	char *force (int size)
96			{
97	root	1.8	if (expect_false (ptr + size >= end))
98	root	1.13	reserve (size);
99	root	1.1
100			return ptr;
101			}
102
103	root	1.26	// allocate size bytes and return pointer to them (caller must force())
104	root	1.10	char *falloc (int size)
105	root	1.1	{
106	root	1.10	char *res = ptr;
107	root	1.9	ptr += size;
108	root	1.1	return res;
109			}
110
111	root	1.26	// allocate size bytes and return pointer to them
112	root	1.10	char *alloc (int size)
113			{
114			force (size);
115			return falloc (size);
116			}
117
118	root	1.6	void fadd (char c) { *ptr++ = c; }
119	root	1.2	void fadd (unsigned char c) { fadd (char (c)); }
120	root	1.10	void fadd (const void *p, int len)
121			{
122			memcpy (falloc (len), p, len);
123			}
124	root	1.1
125			void add (const void *p, int len)
126			{
127	root	1.10	force (len);
128			fadd (p, len);
129	root	1.1	}
130
131			void add (char c)
132			{
133	root	1.3	alloc (1)[0] = c;
134	root	1.1	}
135
136			void add (const char *s)
137			{
138			add (s, strlen (s));
139			}
140
141	root	1.21	void add (shstr_tmp s)
142	root	1.4	{
143			add (s.s, s.length ());
144			}
145	root	1.1
146	root	1.26	// 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	root	1.1	//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	root	1.21	dynbuf &operator << (shstr_tmp s) { add (s); return *this; }
157	root	1.4	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	root	1.16	//TODO: should optimise the case printf "(name %+d)" as it comes up extremely often
173	root	1.13
174	root	1.20	//using dynbuf::operator <<; // doesn't work, sometimes C++ just suxx
175	root	1.18	// instead we use an ugly template function
176			template<typename T>
177			dynbuf_text &operator << (T c) { (dynbuf )this << c; return *this; }
178
179	root	1.16	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	root	1.13
186	root	1.27	void printf (const char *format, ...) attribute ((format (printf, 2, 3)));
187	root	1.14	void vprintf (const char *format, va_list ap);
188	root	1.13
189			void add_abilities (const char *name, uint32 abilities);
190			void add_paths (const char *name, uint32 paths);
191
192	root	1.26	// 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	root	1.13	// returns the string, linearised and with trailing \0
200	root	1.23	operator char *();
201	root	1.1	};
202
203			#endif
204	root	1.6