[mLib] / buf.c

/* -*-c-*-
 *
 * $Id$
 *
 * Buffer handling
 *
 * (c) 2001 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------* 
 *
 * This file is part of the mLib utilities library.
 *
 * mLib 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.
 * 
 * mLib 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 mLib; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 */

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

#include <assert.h>
#include <string.h>

#include "buf.h"

/*----- Main code ---------------------------------------------------------*/

/* --- @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.
 */

void buf_init(buf *b, void *p, size_t sz)
{
  b->base = b->p = p;
  b->limit = b->p + sz;
  b->f = 0;
}

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

int buf_break(buf *b) { b->f |= BF_BROKEN; return (-1); }

/* --- @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.
 */

void buf_flip(buf *b)
{
  b->limit = b->p;
  b->p = b->base;
}

/* --- @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.
 */

int buf_ensure(buf *b, size_t sz) { return (BENSURE(b, 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.
 */

void *buf_get(buf *b, size_t sz)
{
  void *p;
  if (BENSURE(b, sz))
    return (0);
  p = BCUR(b);
  BSTEP(b, sz);
  return (p);
}

/* --- @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
 */

int buf_put(buf *b, const void *p, size_t sz)
{
  if (BENSURE(b, sz))
    return (-1);
  memcpy(BCUR(b), p, sz);
  BSTEP(b, sz);
  return (0);
}

/* --- @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.
 */

int buf_getbyte(buf *b)
{
  if (BENSURE(b, 1))
    return (-1);
  return (*b->p++);
}

/* --- @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.
 */

int buf_putbyte(buf *b, int ch)
{
  if (BENSURE(b, 1))
    return (-1);
  *b->p++ = ch;
  return (0);
}

/* --- @buf_getu{8,{16,24,32,64}{,l,b}}@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@uintSZ *w@ = where to put the word
 *
 * Returns:	Zero if OK, or nonzero if there wasn't a word there.
 *
 * Use:		Gets a word of appropriate size and order from a buffer.
 */

#define BUF_GETU_(n, W, w)						\
  int buf_getu##w(buf *b, uint##n *ww)					\
  {									\
    if (BENSURE(b, SZ_##W)) return (-1);				\
    *ww = LOAD##W(b->p);						\
    BSTEP(b, SZ_##W);							\
    return (0);								\
  }
DOUINTCONV(BUF_GETU_)

/* --- @buf_putu{8,{16,24,32,64}{,l,b}}@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@uintSZ w@ = word to write
 *
 * Returns:	Zero if OK, or nonzero if there wasn't enough space
 *
 * Use:		Puts a word into a buffer with appropriate size and order.
 */

#define BUF_PUTU_(n, W, w)						\
  int buf_putu##w(buf *b, uint##n ww)					\
  {									\
    if (BENSURE(b, SZ_##W)) return (-1);				\
    STORE##W(b->p, ww);							\
    BSTEP(b, SZ_##W);							\
    return (0);								\
  }
DOUINTCONV(BUF_PUTU_)

/* --- @findz@ --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@size_t *nn@ = where to put the length
 *
 * Returns:	Zero if OK, nonzero if there wasn't a null byte to be found.
 *
 * Use:		Finds a terminating null byte.
 */

static int findz(buf *b, size_t *nn)
{
  octet *p;

  if ((p = memchr(BCUR(b), 0, BLEN(b))) == 0) {
    buf_break(b);
    return (-1);
  }
  *nn = p - BCUR(b);
  return (0);
}

/* --- @buf_getmem{8,{16,24,32,64}{,l,b},z} --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@size_t *nn@ = where to put the length
 *
 * Returns:	Pointer to the buffer data, or null.
 *
 * Use:		Gets a chunk of memory from a buffer.  The suffix is the
 *		width and byte order of the length; @z@ means null-
 *		terminated.
 */

#define BUF_GETMEM_(n, W, w)						\
  void *buf_getmem##w(buf *b, size_t *nn)				\
  {									\
    uint##n sz;								\
    if (buf_getu##n(b, &sz)) return (0);				\
    *nn = sz;								\
    return (buf_get(b, sz));						\
  }
DOUINTCONV(BUF_GETMEM_)

void *buf_getmemz(buf *b, size_t *nn)
{
  if (findz(b, nn)) return (0);
  return (buf_get(b, *nn));
}

/* --- @buf_putmem{8,{16,24,32,64}{,l,b},z} --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@const void *p@ = pointer to data to write
 *		@size_t n@ = length to write
 *
 * Returns:	Zero if OK, nonzero if there wasn't enough space.
 *
 * Use:		Writes a chunk of data to a buffer.  The suffix is the
 *		width and byte order of the length; @z@ means null-
 *		terminated.
 */

#define BUF_PUTMEM_(n, W, w)						\
  int buf_putmem##w(buf *b, const void *p, size_t sz)			\
  {									\
    assert(sz <= MASK##W);						\
    if (buf_putu##n(b, sz) || buf_put(b, p, sz))			\
      return (-1);							\
    return (0);								\
  }
DOUINTCONV(BUF_PUTMEM_)

int buf_putmemz(buf *b, const void *p, size_t n)
{
  octet *q;

  assert(!memchr(p, 0, n));
  if ((q = buf_get(b, n + 1)) == 0)
    return (-1);
  memcpy(q, p, n);
  q[n] = 0;
  return (0);
}

/* --- @buf_getbuf{8,{16,24,32,64}{,l,b},z} --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@buf *bb@ = where to put the result
 *
 * Returns:	Zero if it worked, nonzero if there wasn't enough space.
 *
 * Use:		Gets a block of data from a buffer, and writes its bounds to
 *		another buffer.
 */

#define BUF_GETBUF_(n, W, w)						\
  int buf_getbuf##w(buf *b, buf *bb)					\
  {									\
    void *p;								\
    size_t sz;								\
									\
    if ((p = buf_getmem##w(b, &sz)) == 0)				\
      return (-1);							\
    buf_init(bb, p, sz);						\
    return (0);								\
  }
BUF_DOSUFFIXES(BUF_GETBUF_)

/* --- @buf_putbuf{8,{16,24,32,64}{,l,b},z} --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@buf *bb@ = buffer to write
 *
 * Returns:	Zero if it worked, nonzero if there wasn't enough space.
 *
 * Use:		Puts the contents of a buffer to a buffer.
 */

#define BUF_PUTBUF_(n, W, w)						\
  int buf_putbuf##w(buf *b, buf *bb)					\
    { return (buf_putmem##w(b, BBASE(bb), BLEN(bb))); }
BUF_DOSUFFIXES(BUF_PUTBUF_)

/* --- @buf_putstr{8,{16,24,32,64}{,l,b},z} --- *
 *
 * Arguments:	@buf *b@ = pointer to a buffer block
 *		@const char *p@ = string to write
 *
 * Returns:	Zero if it worked, nonzero if there wasn't enough space.
 *
 * Use:		Puts a null-terminated string to a buffer.
 */

#define BUF_PUTSTR_(n, W, w)						\
  int buf_putstr##w(buf *b, const char *p)				\
    { return (buf_putmem##w(b, p, strlen(p))); }
BUF_DOSUFFIXES(BUF_PUTSTR_)

/*----- That's all, folks -------------------------------------------------*/
Commit	Line	Data
800d4c59	1	/* --c--
	2	*
	3	* $Id$
	4	*
	5	* Buffer handling
	6	*
	7	* (c) 2001 Straylight/Edgeware
	8	*/
	9
	10	/----- Licensing notice --------------------------------------------------
	11	*
9b5ac6ff	12	* This file is part of the mLib utilities library.
800d4c59	13	*
9b5ac6ff	14	* mLib is free software; you can redistribute it and/or modify
800d4c59	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	*
9b5ac6ff	19	* mLib is distributed in the hope that it will be useful,
800d4c59	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
9b5ac6ff	25	* License along with mLib; if not, write to the Free
800d4c59	26	* Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
	27	* MA 02111-1307, USA.
	28	*/
	29
	30	/----- Header files ------------------------------------------------------/
	31
9b5ac6ff	32	#include <assert.h>
800d4c59	33	#include <string.h>
800d4c59	34
800d4c59	35	#include "buf.h"
	36
	37	/----- Main code ---------------------------------------------------------/
	38
	39	/* --- @buf_init@ --- *
	40	*
	41	* Arguments: @buf *b@ = pointer to a buffer block
	42	* @void *p@ = pointer to a buffer
	43	* @size_t sz@ = size of the buffer
	44	*
	45	* Returns: ---
	46	*
	47	* Use: Initializes the buffer block appropriately.
	48	*/
	49
	50	void buf_init(buf b, void p, size_t sz)
	51	{
	52	b->base = b->p = p;
	53	b->limit = b->p + sz;
	54	b->f = 0;
	55	}
	56
	57	/* --- @buf_break@ --- *
	58	*
	59	* Arguments: @buf *b@ = pointer to a buffer block
	60	*
	61	* Returns: Some negative value.
	62	*
	63	* Use: Marks a buffer as broken.
	64	*/
	65
	66	int buf_break(buf *b) { b->f \|= BF_BROKEN; return (-1); }
	67
	68	/* --- @buf_flip@ --- *
	69	*
	70	* Arguments: @buf *b@ = pointer to a buffer block
	71	*
	72	* Returns: ---
	73	*
	74	* Use: Flips a buffer so that if you've just been writing to it,
	75	* you can now read from the bit you've written.
	76	*/
	77
	78	void buf_flip(buf *b)
	79	{
	80	b->limit = b->p;
	81	b->p = b->base;
	82	}
	83
	84	/* --- @buf_ensure@ --- *
	85	*
	86	* Arguments: @buf *b@ = pointer to a buffer block
	87	* @size_t sz@ = size of data wanted
	88	*
	89	* Returns: Zero if it worked, nonzero if there wasn't enough space.
	90	*
	91	* Use: Ensures that there are @sz@ bytes still in the buffer.
	92	*/
	93
	94	int buf_ensure(buf *b, size_t sz) { return (BENSURE(b, sz)); }
	95
	96	/* --- @buf_get@ --- *
	97	*
	98	* Arguments: @buf *b@ = pointer to a buffer block
99	* @size_t sz@ = size of the buffer
100	*
101	* Returns: Pointer to the place in the buffer.
102	*
103	* Use: Reserves a space in the buffer of the requested size, and
104	* returns its start address.
105	*/
106
107	void buf_get(buf b, size_t sz)
108	{
109	void *p;
110	if (BENSURE(b, sz))
111	return (0);
112	p = BCUR(b);
113	BSTEP(b, sz);
114	return (p);
115	}
116
117	/* --- @buf_put@ --- *
118	*
119	* Arguments: @buf *b@ = pointer to a buffer block
120	* @const void *p@ = pointer to a buffer
121	* @size_t sz@ = size of the buffer
122	*
123	* Returns: Zero if it worked, nonzero if there wasn't enough space.
124	*
125	* Use: Fetches data from some place and puts it in the buffer
126	*/
127
128	int buf_put(buf b, const void p, size_t sz)
129	{
130	if (BENSURE(b, sz))
131	return (-1);
132	memcpy(BCUR(b), p, sz);
133	BSTEP(b, sz);
134	return (0);
135	}
136
137	/* --- @buf_getbyte@ --- *
138	*
139	* Arguments: @buf *b@ = pointer to a buffer block
140	*
141	* Returns: A byte, or less than zero if there wasn't a byte there.
142	*
143	* Use: Gets a single byte from a buffer.
144	*/
145
146	int buf_getbyte(buf *b)
147	{
148	if (BENSURE(b, 1))
149	return (-1);
150	return (*b->p++);
151	}
152
153	/* --- @buf_putbyte@ --- *
154	*
155	* Arguments: @buf *b@ = pointer to a buffer block
156	* @int ch@ = byte to write
157	*
158	* Returns: Zero if OK, nonzero if there wasn't enough space.
159	*
160	* Use: Puts a single byte in a buffer.
161	*/
162
163	int buf_putbyte(buf *b, int ch)
164	{
165	if (BENSURE(b, 1))
166	return (-1);
167	*b->p++ = ch;
168	return (0);
169	}
170
9b5ac6ff	171	/* --- @buf_getu{8,{16,24,32,64}{,l,b}}@ --- *
800d4c59	172	*
800d4c59	173	* Arguments: @buf *b@ = pointer to a buffer block
9b5ac6ff	174	* @uintSZ *w@ = where to put the word
800d4c59	175	*
	176	* Returns: Zero if OK, or nonzero if there wasn't a word there.
	177	*
9b5ac6ff	178	* Use: Gets a word of appropriate size and order from a buffer.
800d4c59	179	*/
800d4c59	180
9b5ac6ff	181	#define BUF_GETU_(n, W, w) \
	182	int buf_getu##w(buf b, uint##n ww) \
	183	{ \
	184	if (BENSURE(b, SZ_##W)) return (-1); \
	185	*ww = LOAD##W(b->p); \
	186	BSTEP(b, SZ_##W); \
	187	return (0); \
	188	}
	189	DOUINTCONV(BUF_GETU_)
800d4c59	190
9b5ac6ff	191	/* --- @buf_putu{8,{16,24,32,64}{,l,b}}@ --- *
800d4c59	192	*
800d4c59	193	* Arguments: @buf *b@ = pointer to a buffer block
9b5ac6ff	194	* @uintSZ w@ = word to write
800d4c59	195	*
9b5ac6ff	196	* Returns: Zero if OK, or nonzero if there wasn't enough space
800d4c59	197	*
9b5ac6ff	198	* Use: Puts a word into a buffer with appropriate size and order.
800d4c59	199	*/
800d4c59	200
9b5ac6ff	201	#define BUF_PUTU_(n, W, w) \
	202	int buf_putu##w(buf *b, uint##n ww) \
	203	{ \
	204	if (BENSURE(b, SZ_##W)) return (-1); \
	205	STORE##W(b->p, ww); \
	206	BSTEP(b, SZ_##W); \
	207	return (0); \
	208	}
	209	DOUINTCONV(BUF_PUTU_)
800d4c59	210
	211	/* --- @findz@ --- *
	212	*
	213	* Arguments: @buf *b@ = pointer to a buffer block
	214	* @size_t *nn@ = where to put the length
	215	*
	216	* Returns: Zero if OK, nonzero if there wasn't a null byte to be found.
	217	*
	218	* Use: Finds a terminating null byte.
	219	*/
	220
	221	static int findz(buf b, size_t nn)
	222	{
	223	octet *p;
	224
	225	if ((p = memchr(BCUR(b), 0, BLEN(b))) == 0) {
	226	buf_break(b);
	227	return (-1);
	228	}
	229	*nn = p - BCUR(b);
	230	return (0);
	231	}
	232
9b5ac6ff	233	/* --- @buf_getmem{8,{16,24,32,64}{,l,b},z} --- *
800d4c59	234	*
	235	* Arguments: @buf *b@ = pointer to a buffer block
	236	* @size_t *nn@ = where to put the length
	237	*
	238	* Returns: Pointer to the buffer data, or null.
	239	*
9b5ac6ff	240	* Use: Gets a chunk of memory from a buffer. The suffix is the
	241	* width and byte order of the length; @z@ means null-
	242	* terminated.
800d4c59	243	*/
800d4c59	244
9b5ac6ff	245	#define BUF_GETMEM_(n, W, w) \
	246	void buf_getmem##w(buf b, size_t *nn) \
	247	{ \
	248	uint##n sz; \
	249	if (buf_getu##n(b, &sz)) return (0); \
	250	*nn = sz; \
	251	return (buf_get(b, sz)); \
	252	}
	253	DOUINTCONV(BUF_GETMEM_)
800d4c59	254
800d4c59	255	void buf_getmemz(buf b, size_t *nn)
	256	{
	257	if (findz(b, nn)) return (0);
	258	return (buf_get(b, *nn));
	259	}
	260
9b5ac6ff	261	/* --- @buf_putmem{8,{16,24,32,64}{,l,b},z} --- *
800d4c59	262	*
	263	* Arguments: @buf *b@ = pointer to a buffer block
	264	* @const void *p@ = pointer to data to write
	265	* @size_t n@ = length to write
	266	*
	267	* Returns: Zero if OK, nonzero if there wasn't enough space.
	268	*
9b5ac6ff	269	* Use: Writes a chunk of data to a buffer. The suffix is the
	270	* width and byte order of the length; @z@ means null-
	271	* terminated.
800d4c59	272	*/
800d4c59	273
9b5ac6ff	274	#define BUF_PUTMEM_(n, W, w) \
	275	int buf_putmem##w(buf b, const void p, size_t sz) \
	276	{ \
	277	assert(sz <= MASK##W); \
	278	if (buf_putu##n(b, sz) \|\| buf_put(b, p, sz)) \
	279	return (-1); \
	280	return (0); \
	281	}
	282	DOUINTCONV(BUF_PUTMEM_)
800d4c59	283
	284	int buf_putmemz(buf b, const void p, size_t n)
	285	{
	286	octet *q;
	287
	288	assert(!memchr(p, 0, n));
	289	if ((q = buf_get(b, n + 1)) == 0)
	290	return (-1);
	291	memcpy(q, p, n);
	292	q[n] = 0;
	293	return (0);
	294	}
	295
9b5ac6ff	296	/* --- @buf_getbuf{8,{16,24,32,64}{,l,b},z} --- *
800d4c59	297	*
	298	* Arguments: @buf *b@ = pointer to a buffer block
	299	* @buf *bb@ = where to put the result
	300	*
	301	* Returns: Zero if it worked, nonzero if there wasn't enough space.
	302	*
	303	* Use: Gets a block of data from a buffer, and writes its bounds to
9b5ac6ff	304	* another buffer.
800d4c59	305	*/
800d4c59	306
9b5ac6ff	307	#define BUF_GETBUF_(n, W, w) \
	308	int buf_getbuf##w(buf b, buf bb) \
	309	{ \
	310	void *p; \
	311	size_t sz; \
800d4c59	312	\
9b5ac6ff	313	if ((p = buf_getmem##w(b, &sz)) == 0) \
	314	return (-1); \
	315	buf_init(bb, p, sz); \
	316	return (0); \
800d4c59	317	}
9b5ac6ff	318	BUF_DOSUFFIXES(BUF_GETBUF_)
800d4c59	319
9b5ac6ff	320	/* --- @buf_putbuf{8,{16,24,32,64}{,l,b},z} --- *
800d4c59	321	*
800d4c59	322	* Arguments: @buf *b@ = pointer to a buffer block
9b5ac6ff	323	* @buf *bb@ = buffer to write
800d4c59	324	*
	325	* Returns: Zero if it worked, nonzero if there wasn't enough space.
	326	*
9b5ac6ff	327	* Use: Puts the contents of a buffer to a buffer.
800d4c59	328	*/
800d4c59	329
9b5ac6ff	330	#define BUF_PUTBUF_(n, W, w) \
	331	int buf_putbuf##w(buf b, buf bb) \
	332	{ return (buf_putmem##w(b, BBASE(bb), BLEN(bb))); }
	333	BUF_DOSUFFIXES(BUF_PUTBUF_)
800d4c59	334
9b5ac6ff	335	/* --- @buf_putstr{8,{16,24,32,64}{,l,b},z} --- *
800d4c59	336	*
800d4c59	337	* Arguments: @buf *b@ = pointer to a buffer block
9b5ac6ff	338	* @const char *p@ = string to write
800d4c59	339	*
	340	* Returns: Zero if it worked, nonzero if there wasn't enough space.
	341	*
9b5ac6ff	342	* Use: Puts a null-terminated string to a buffer.
800d4c59	343	*/
800d4c59	344
9b5ac6ff	345	#define BUF_PUTSTR_(n, W, w) \
	346	int buf_putstr##w(buf b, const char p) \
	347	{ return (buf_putmem##w(b, p, strlen(p))); }
	348	BUF_DOSUFFIXES(BUF_PUTSTR_)
800d4c59	349
800d4c59	350	/----- That's all, folks -------------------------------------------------/