server/include/dynbuf.h

/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 *
 * Copyright (©) 2005,2006,2007,2008,2009,2010,2011,2012,2013,2014,2015,2016 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
 * Copyright (©) 2002 Mark Wedel & Crossfire Development Team
 * Copyright (©) 1992 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 "compiler.h"
#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);

    ecb_assume (ptr + size <= end);

    return ptr;
  }

  // used for force + alloc combo
  void alloc (char *p)
  {
    ptr = p;
  }

  // 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, ...) ecb_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:	1.37
Committed:	Sat Nov 17 23:33:18 2018 UTC (5 years, 6 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.36:	+2 -2 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.11	/*
2	root	1.15	* This file is part of Deliantra, the Roguelike Realtime MMORPG.
3	root	1.34	*
4	root	1.35	* Copyright (©) 2005,2006,2007,2008,2009,2010,2011,2012,2013,2014,2015,2016 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5	root	1.30	* Copyright (©) 2002 Mark Wedel & Crossfire Development Team
6			* Copyright (©) 1992 Frank Tore Johansen
7	root	1.34	*
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	1.34	*
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	1.34	*
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	1.34	*
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	1.28	#include "compiler.h"
32	root	1.8	#include "util.h"
33	root	1.4	#include "shstr.h"
34
35	root	1.1	// this is a "buffer" that can grow fast
36			// and is still somewhat space-efficient.
37			// unlike obstacks or other data structures,
38			// it never moves data around. basically,
39			// this is a fast strstream without the overhead.
40
41	root	1.4	struct dynbuf
42	root	1.1	{
43	root	1.4	protected:
44	root	1.1	struct chunk
45			{
46			chunk *next;
47	root	1.5	int alloc;
48	root	1.1	int size;
49			char data[0];
50			};
51
52	root	1.6	char ptr, end;
53	root	1.1	int _size;
54
55	root	1.19	int extend, cextend;
56	root	1.1	chunk first, last;
57
58	root	1.13	void reserve (int size);
59			void init (int initial); // allocate sinitial chunk
60			void free (chunk *&chain); // free chain of chunks
61	root	1.26	char *_linearise (int extra = 0);
62	root	1.13	void finalise ();
63	root	1.1
64			public:
65
66	root	1.13	// initial - the size of the initial chunk to be allocated
67			// extend - first incremental step when buffer size exceeded
68			dynbuf (int initial = 4096, int extend = 16384)
69			: extend (extend)
70			{
71			init (initial);
72			}
73
74			~dynbuf ()
75			{
76			free (first);
77			}
78
79			// resets the dynbuf, but does not free the first chunk
80			// which is either of size "initial" or the size of the last
81			// linearise
82			void clear ();
83	root	1.1
84	root	1.6	int size () const { return _size + (ptr - last->data); }
85			bool empty () const { return !size (); }
86	root	1.1
87			void linearise (void *data);
88	root	1.13	char *linearise () // does not 0-terminate(!)
89	root	1.36	{
90	root	1.13	return first->next ? _linearise () : first->data;
91			}
92	root	1.6
93			int room () const { return end - ptr; }
94	root	1.1
95	root	1.26	// make sure we have "size" extra room
96	root	1.1	char *force (int size)
97			{
98	root	1.28	if (expect_false (ptr + size > end))
99	root	1.13	reserve (size);
100	root	1.1
101	root	1.37	ecb_assume (ptr + size <= end);
102	root	1.28
103	root	1.1	return ptr;
104			}
105
106	root	1.29	// used for force + alloc combo
107			void alloc (char *p)
108			{
109			ptr = p;
110			}
111
112	root	1.26	// allocate size bytes and return pointer to them (caller must force())
113	root	1.10	char *falloc (int size)
114	root	1.1	{
115	root	1.10	char *res = ptr;
116	root	1.9	ptr += size;
117	root	1.1	return res;
118			}
119
120	root	1.26	// allocate size bytes and return pointer to them
121	root	1.10	char *alloc (int size)
122			{
123			force (size);
124			return falloc (size);
125			}
126
127	root	1.6	void fadd (char c) { *ptr++ = c; }
128	root	1.2	void fadd (unsigned char c) { fadd (char (c)); }
129	root	1.10	void fadd (const void *p, int len)
130			{
131			memcpy (falloc (len), p, len);
132			}
133	root	1.1
134			void add (const void *p, int len)
135			{
136	root	1.10	force (len);
137			fadd (p, len);
138	root	1.1	}
139
140			void add (char c)
141			{
142	root	1.3	alloc (1)[0] = c;
143	root	1.1	}
144
145			void add (const char *s)
146			{
147			add (s, strlen (s));
148			}
149
150	root	1.21	void add (shstr_tmp s)
151	root	1.4	{
152			add (s.s, s.length ());
153			}
154	root	1.1
155	root	1.26	// rather inefficient
156			void splice (int offset, int olen, const char *s, int slen);
157			void splice (int offset, int olen) { splice (offset, olen, "", 0); }
158
159	root	1.1	//TODO
160			//void add_destructive (dynbuf &buf);
161
162			dynbuf &operator << (char c) { add (c); return *this; }
163			dynbuf &operator << (unsigned char c) { return *this << char (c); }
164			dynbuf &operator << (const char s) { add (s); return this; }
165	root	1.21	dynbuf &operator << (shstr_tmp s) { add (s); return *this; }
166	root	1.4	dynbuf &operator << (const std::string &s) { add (s.data(), s.size ()); return *this; }
167
168			operator std::string ();
169			};
170
171			struct dynbuf_text : dynbuf
172			{
173			dynbuf_text (int initial = 4096, int extend = 16384)
174			: dynbuf (initial, extend)
175			{ }
176
177			using dynbuf::add;
178			void add (sint32 i);
179			void add (sint64 i);
180
181	root	1.16	//TODO: should optimise the case printf "(name %+d)" as it comes up extremely often
182	root	1.13
183	root	1.20	//using dynbuf::operator <<; // doesn't work, sometimes C++ just suxx
184	root	1.18	// instead we use an ugly template function
185			template<typename T>
186			dynbuf_text &operator << (T c) { (dynbuf )this << c; return *this; }
187
188	root	1.16	dynbuf_text &operator << (sint16 i) { add (sint32 (i)); return *this; }
189			dynbuf_text &operator << (uint16 i) { add (sint32 (i)); return *this; }
190			dynbuf_text &operator << (sint32 i) { add (sint32 (i)); return *this; }
191			dynbuf_text &operator << (sint64 i) { add (sint64 (i)); return *this; }
192			dynbuf_text &operator << (uint32 i) { add (sint64 (i)); return *this; }
193			dynbuf_text &operator << (uint64 i) { add (sint64 (i)); return *this; }
194	root	1.13
195	root	1.37	void printf (const char *format, ...) ecb_attribute ((format (printf, 2, 3)));
196	root	1.14	void vprintf (const char *format, va_list ap);
197	root	1.13
198			void add_abilities (const char *name, uint32 abilities);
199			void add_paths (const char *name, uint32 paths);
200
201	root	1.26	// we need to redefine, to keep the API :/
202			using dynbuf::splice;
203			void splice (int offset, int olen, const char *s)
204			{
205			dynbuf::splice (offset, olen, s, strlen (s));
206			}
207
208	root	1.13	// returns the string, linearised and with trailing \0
209	root	1.23	operator char *();
210	root	1.1	};
211
212			#endif
213	root	1.6