[u/mdw/catacomb] / buf.h

/* -*-c-*-
 *
 * $Id: buf.h,v 1.2 2003/11/10 22:18:30 mdw Exp $
 *
 * Reading and writing packet buffers
 *
 * (c) 2001 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------* 
 *
 * This file is part of Catacomb.
 *
 * Catacomb is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Library General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 * 
 * Catacomb 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 Library General Public License for more details.
 * 
 * You should have received a copy of the GNU Library General Public
 * License along with Catacomb; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 */

/*----- Revision history --------------------------------------------------* 
 *
 * $Log: buf.h,v $
 * Revision 1.2  2003/11/10 22:18:30  mdw
 * Build fixes.
 *
 * Revision 1.1  2003/10/11 21:02:33  mdw
 * Import buf stuff from tripe.
 *
 * Revision 1.1  2001/06/19 22:09:54  mdw
 * Expose interface, for use in the proxy.
 *
 */

#ifndef CATACOMB_BUF_H
#define CATACOMB_BUF_H

#ifdef __cplusplus
  extern "C" {
#endif

/*----- Header files ------------------------------------------------------*/

#include <stddef.h>

#include <mLib/bits.h>

#ifndef CATACOMB_MP_H
#  include "mp.h"
#endif

/*----- Data structures ---------------------------------------------------*/

/* --- Buffers --- *
 *
 * Buffers provide a simple stream-like interface for building and parsing
 * packets.
 */

typedef struct buf {
  octet *base, *p, *limit;		/* Pointers to the buffer */
  unsigned f;				/* Various flags */
} buf;

#define BF_BROKEN 1u			/* Buffer is broken */

/*----- Useful macros -----------------------------------------------------*/

#define BBASE(b) ((b)->base)
#define BLIM(b) ((b)->limit)
#define BCUR(b) ((b)->p)
#define BSZ(b) ((b)->limit - (b)->base)
#define BLEN(b) ((b)->p - (b)->base)
#define BLEFT(b) ((b)->limit - (b)->p)
#define BSTEP(b, sz) ((b)->p += (sz))
#define BBAD(b) ((b)->f & BF_BROKEN)
#define BOK(b) (!BBAD(b))

#define BENSURE(b, sz)							\
  (BBAD(b) ? -1 : (sz) > BLEFT(b) ? (b)->f |= BF_BROKEN, -1 : 0)

/*----- Functions provided ------------------------------------------------*/

/* --- @buf_init@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@void *p@ = pointer to a buffer
 *		@size_t sz@ = size of the buffer
 *
 * Returns:	---
 *
 * Use:		Initializes the buffer block appropriately.
 */

extern void buf_init(buf */*b*/, void */*p*/, size_t /*sz*/);

/* --- @buf_break@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *
 * Returns:	Some negative value.
 *
 * Use:		Marks a buffer as broken.
 */

extern int buf_break(buf */*b*/);

/* --- @buf_flip@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *
 * Returns:	---
 *
 * Use:		Flips a buffer so that if you've just been writing to it,
 *		you can now read from the bit you've written.
 */

extern void buf_flip(buf */*b*/);

/* --- @buf_ensure@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@size_t sz@ = size of data wanted
 *
 * Returns:	Zero if it worked, nonzero if there wasn't enough space.
 *
 * Use:		Ensures that there are @sz@ bytes still in the buffer.
 */

extern int buf_ensure(buf */*b*/, size_t /*sz*/);

/* --- @buf_get@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@size_t sz@ = size of the buffer
 *
 * Returns:	Pointer to the place in the buffer.
 *
 * Use:		Reserves a space in the buffer of the requested size, and
 *		returns its start address.
 */

extern void *buf_get(buf */*b*/, size_t /*sz*/);

/* --- @buf_put@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@const void *p@ = pointer to a buffer
 *		@size_t sz@ = size of the buffer
 *
 * Returns:	Zero if it worked, nonzero if there wasn't enough space.
 *
 * Use:		Fetches data from some place and puts it in the buffer
 */

extern int buf_put(buf */*b*/, const void */*p*/, size_t /*sz*/);

/* --- @buf_getbyte@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *
 * Returns:	A byte, or less than zero if there wasn't a byte there.
 *
 * Use:		Gets a single byte from a buffer.
 */

extern int buf_getbyte(buf */*b*/);

/* --- @buf_putbyte@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@int ch@ = byte to write
 *
 * Returns:	Zero if OK, nonzero if there wasn't enough space.
 *
 * Use:		Puts a single byte in a buffer.
 */

extern int buf_putbyte(buf */*b*/, int /*ch*/);

/* --- @buf_getu16@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@uint16 *w@ = where to put the word
 *
 * Returns:	Zero if OK, or nonzero if there wasn't a word there.
 *
 * Use:		Gets a 16-bit word from a buffer.
 */

extern int buf_getu16(buf */*b*/, uint16 */*w*/);

/* --- @buf_putu16@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@uint16 w@ = word to write
 *
 * Returns:	Zero if OK, nonzero if there wasn't enough space.
 *
 * Use:		Puts a 16-but word in a buffer.
 */

extern int buf_putu16(buf */*b*/, uint16 /*w*/);

/* --- @buf_getu32@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@uint32 *w@ = where to put the word
 *
 * Returns:	Zero if OK, or nonzero if there wasn't a word there.
 *
 * Use:		Gets a 32-bit word from a buffer.
 */

extern int buf_getu32(buf */*b*/, uint32 */*w*/);

/* --- @buf_putu32@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@uint32 w@ = word to write
 *
 * Returns:	Zero if OK, nonzero if there wasn't enough space.
 *
 * Use:		Puts a 32-but word in a buffer.
 */

extern int buf_putu32(buf */*b*/, uint32 /*w*/);

/* --- @buf_getmp@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *
 * Returns:	A multiprecision integer, or null if there wasn't one there.
 *
 * Use:		Gets a multiprecision integer from a buffer.
 */

extern mp *buf_getmp(buf */*b*/);

/* --- @buf_putmp@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@mp *m@ = a multiprecision integer
 *
 * Returns:	Zero if it worked, nonzero if there wasn't enough space.
 *
 * Use:		Puts a multiprecision integer to a buffer.
 */

extern int buf_putmp(buf */*b*/, mp */*m*/);

/*----- That's all, folks -------------------------------------------------*/

#ifdef __cplusplus
  }
#endif

#endif
Commit	Line	Data
6b80b6c4	1	/* --c--
6b80b6c4	2	*
5ff5e658	3	* $Id: buf.h,v 1.2 2003/11/10 22:18:30 mdw Exp $
	4	*
	5	* Reading and writing packet buffers
6b80b6c4	6	*
6b80b6c4	7	* (c) 2001 Straylight/Edgeware
	8	*/
	9
	10	/----- Licensing notice --------------------------------------------------
	11	*
	12	* This file is part of Catacomb.
	13	*
	14	* Catacomb is free software; you can redistribute it and/or modify
	15	* it under the terms of the GNU Library General Public License as
	16	* published by the Free Software Foundation; either version 2 of the
	17	* License, or (at your option) any later version.
	18	*
	19	* Catacomb is distributed in the hope that it will be useful,
	20	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	21	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	22	* GNU Library General Public License for more details.
	23	*
	24	* You should have received a copy of the GNU Library General Public
	25	* License along with Catacomb; if not, write to the Free
	26	* Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
	27	* MA 02111-1307, USA.
	28	*/
	29
	30	/----- Revision history --------------------------------------------------
	31	*
	32	* $Log: buf.h,v $
5ff5e658	33	* Revision 1.2 2003/11/10 22:18:30 mdw
	34	* Build fixes.
	35	*
6b80b6c4	36	* Revision 1.1 2003/10/11 21:02:33 mdw
	37	* Import buf stuff from tripe.
	38	*
	39	* Revision 1.1 2001/06/19 22:09:54 mdw
	40	* Expose interface, for use in the proxy.
	41	*
	42	*/
	43
5ff5e658	44	#ifndef CATACOMB_BUF_H
5ff5e658	45	#define CATACOMB_BUF_H
6b80b6c4	46
	47	#ifdef __cplusplus
	48	extern "C" {
	49	#endif
	50
	51	/----- Header files ------------------------------------------------------/
	52
	53	#include <stddef.h>
	54
	55	#include <mLib/bits.h>
	56
5ff5e658	57	#ifndef CATACOMB_MP_H
	58	# include "mp.h"
	59	#endif
6b80b6c4	60
	61	/----- Data structures ---------------------------------------------------/
	62
	63	/* --- Buffers --- *
	64	*
	65	* Buffers provide a simple stream-like interface for building and parsing
	66	* packets.
	67	*/
	68
	69	typedef struct buf {
	70	octet base, p, limit; / Pointers to the buffer */
	71	unsigned f; /* Various flags */
	72	} buf;
	73
	74	#define BF_BROKEN 1u /* Buffer is broken */
	75
	76	/----- Useful macros -----------------------------------------------------/
	77
	78	#define BBASE(b) ((b)->base)
	79	#define BLIM(b) ((b)->limit)
	80	#define BCUR(b) ((b)->p)
	81	#define BSZ(b) ((b)->limit - (b)->base)
	82	#define BLEN(b) ((b)->p - (b)->base)
	83	#define BLEFT(b) ((b)->limit - (b)->p)
	84	#define BSTEP(b, sz) ((b)->p += (sz))
	85	#define BBAD(b) ((b)->f & BF_BROKEN)
	86	#define BOK(b) (!BBAD(b))
	87
	88	#define BENSURE(b, sz) \
	89	(BBAD(b) ? -1 : (sz) > BLEFT(b) ? (b)->f \|= BF_BROKEN, -1 : 0)
	90
	91	/----- Functions provided ------------------------------------------------/
	92
	93	/* --- @buf_init@ --- *
	94	*
	95	* Arguments: @buf *b@ = pointer to a buffer block
	96	* @void *p@ = pointer to a buffer
	97	* @size_t sz@ = size of the buffer
	98	*
	99	* Returns: ---
	100	*
	101	* Use: Initializes the buffer block appropriately.
	102	*/
	103
	104	extern void buf_init(buf /b/, void /p/, size_t /sz/);
	105
	106	/* --- @buf_break@ --- *
	107	*
	108	* Arguments: @buf *b@ = pointer to a buffer block
	109	*
	110	* Returns: Some negative value.
	111	*
	112	* Use: Marks a buffer as broken.
	113	*/
	114
	115	extern int buf_break(buf /b*/);
	116
	117	/* --- @buf_flip@ --- *
	118	*
	119	* Arguments: @buf *b@ = pointer to a buffer block
	120	*
	121	* Returns: ---
	122	*
	123	* Use: Flips a buffer so that if you've just been writing to it,
124	* you can now read from the bit you've written.
125	*/
126
127	extern void buf_flip(buf /b*/);
128
129	/* --- @buf_ensure@ --- *
130	*
131	* Arguments: @buf *b@ = pointer to a buffer block
132	* @size_t sz@ = size of data wanted
133	*
134	* Returns: Zero if it worked, nonzero if there wasn't enough space.
135	*
136	* Use: Ensures that there are @sz@ bytes still in the buffer.
137	*/
138
139	extern int buf_ensure(buf /b/, size_t /sz*/);
140
141	/* --- @buf_get@ --- *
142	*
143	* Arguments: @buf *b@ = pointer to a buffer block
144	* @size_t sz@ = size of the buffer
145	*
146	* Returns: Pointer to the place in the buffer.
147	*
148	* Use: Reserves a space in the buffer of the requested size, and
149	* returns its start address.
150	*/
151
152	extern void buf_get(buf /b/, size_t /sz/);
153
154	/* --- @buf_put@ --- *
155	*
156	* Arguments: @buf *b@ = pointer to a buffer block
157	* @const void *p@ = pointer to a buffer
158	* @size_t sz@ = size of the buffer
159	*
160	* Returns: Zero if it worked, nonzero if there wasn't enough space.
161	*
162	* Use: Fetches data from some place and puts it in the buffer
163	*/
164
165	extern int buf_put(buf /b/, const void /p/, size_t /sz/);
166
167	/* --- @buf_getbyte@ --- *
168	*
169	* Arguments: @buf *b@ = pointer to a buffer block
170	*
171	* Returns: A byte, or less than zero if there wasn't a byte there.
172	*
173	* Use: Gets a single byte from a buffer.
174	*/
175
176	extern int buf_getbyte(buf /b*/);
177
178	/* --- @buf_putbyte@ --- *
179	*
180	* Arguments: @buf *b@ = pointer to a buffer block
181	* @int ch@ = byte to write
182	*
183	* Returns: Zero if OK, nonzero if there wasn't enough space.
184	*
185	* Use: Puts a single byte in a buffer.
186	*/
187
188	extern int buf_putbyte(buf /b/, int /ch*/);
189
190	/* --- @buf_getu16@ --- *
191	*
192	* Arguments: @buf *b@ = pointer to a buffer block
193	* @uint16 *w@ = where to put the word
194	*
195	* Returns: Zero if OK, or nonzero if there wasn't a word there.
196	*
197	* Use: Gets a 16-bit word from a buffer.
198	*/
199
200	extern int buf_getu16(buf /b/, uint16 /w/);
201
202	/* --- @buf_putu16@ --- *
203	*
204	* Arguments: @buf *b@ = pointer to a buffer block
205	* @uint16 w@ = word to write
206	*
207	* Returns: Zero if OK, nonzero if there wasn't enough space.
208	*
209	* Use: Puts a 16-but word in a buffer.
210	*/
211
212	extern int buf_putu16(buf /b/, uint16 /w*/);
213
214	/* --- @buf_getu32@ --- *
215	*
216	* Arguments: @buf *b@ = pointer to a buffer block
217	* @uint32 *w@ = where to put the word
218	*
219	* Returns: Zero if OK, or nonzero if there wasn't a word there.
220	*
221	* Use: Gets a 32-bit word from a buffer.
222	*/
223
224	extern int buf_getu32(buf /b/, uint32 /w/);
225
226	/* --- @buf_putu32@ --- *
227	*
228	* Arguments: @buf *b@ = pointer to a buffer block
229	* @uint32 w@ = word to write
230	*
231	* Returns: Zero if OK, nonzero if there wasn't enough space.
232	*
233	* Use: Puts a 32-but word in a buffer.
234	*/
235
236	extern int buf_putu32(buf /b/, uint32 /w*/);
237
238	/* --- @buf_getmp@ --- *
239	*
240	* Arguments: @buf *b@ = pointer to a buffer block
241	*
242	* Returns: A multiprecision integer, or null if there wasn't one there.
243	*
244	* Use: Gets a multiprecision integer from a buffer.
245	*/
246
247	extern mp buf_getmp(buf /b/);
248
249	/* --- @buf_putmp@ --- *
250	*
251	* Arguments: @buf *b@ = pointer to a buffer block
252	* @mp *m@ = a multiprecision integer
253	*
254	* Returns: Zero if it worked, nonzero if there wasn't enough space.
255	*
256	* Use: Puts a multiprecision integer to a buffer.
257	*/
258
259	extern int buf_putmp(buf /b/, mp /m/);
260
261	/----- That's all, folks -------------------------------------------------/
262
263	#ifdef __cplusplus
264	}
265	#endif
266
267	#endif