[net-next-2.6.git] / fs / seq_file.c

/*
 * linux/fs/seq_file.c
 *
 * helper functions for making synthetic files from sequences of records.
 * initial implementation -- AV, Oct 2001.
 */

#include <linux/fs.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/slab.h>

#include <asm/uaccess.h>
#include <asm/page.h>

/**
 *	seq_open -	initialize sequential file
 *	@file: file we initialize
 *	@op: method table describing the sequence
 *
 *	seq_open() sets @file, associating it with a sequence described
 *	by @op.  @op->start() sets the iterator up and returns the first
 *	element of sequence. @op->stop() shuts it down.  @op->next()
 *	returns the next element of sequence.  @op->show() prints element
 *	into the buffer.  In case of error ->start() and ->next() return
 *	ERR_PTR(error).  In the end of sequence they return %NULL. ->show()
 *	returns 0 in case of success and negative number in case of error.
 */
int seq_open(struct file *file, struct seq_operations *op)
{
	struct seq_file *p = file->private_data;

	if (!p) {
		p = kmalloc(sizeof(*p), GFP_KERNEL);
		if (!p)
			return -ENOMEM;
		file->private_data = p;
	}
	memset(p, 0, sizeof(*p));
	mutex_init(&p->lock);
	p->op = op;

	/*
	 * Wrappers around seq_open(e.g. swaps_open) need to be
	 * aware of this. If they set f_version themselves, they
	 * should call seq_open first and then set f_version.
	 */
	file->f_version = 0;

	/* SEQ files support lseek, but not pread/pwrite */
	file->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
	return 0;
}
EXPORT_SYMBOL(seq_open);

/**
 *	seq_read -	->read() method for sequential files.
 *	@file: the file to read from
 *	@buf: the buffer to read to
 *	@size: the maximum number of bytes to read
 *	@ppos: the current position in the file
 *
 *	Ready-made ->f_op->read()
 */
ssize_t seq_read(struct file *file, char __user *buf, size_t size, loff_t *ppos)
{
	struct seq_file *m = (struct seq_file *)file->private_data;
	size_t copied = 0;
	loff_t pos;
	size_t n;
	void *p;
	int err = 0;

	mutex_lock(&m->lock);
	/*
	 * seq_file->op->..m_start/m_stop/m_next may do special actions
	 * or optimisations based on the file->f_version, so we want to
	 * pass the file->f_version to those methods.
	 *
	 * seq_file->version is just copy of f_version, and seq_file
	 * methods can treat it simply as file version.
	 * It is copied in first and copied out after all operations.
	 * It is convenient to have it as  part of structure to avoid the
	 * need of passing another argument to all the seq_file methods.
	 */
	m->version = file->f_version;
	/* grab buffer if we didn't have one */
	if (!m->buf) {
		m->buf = kmalloc(m->size = PAGE_SIZE, GFP_KERNEL);
		if (!m->buf)
			goto Enomem;
	}
	/* if not empty - flush it first */
	if (m->count) {
		n = min(m->count, size);
		err = copy_to_user(buf, m->buf + m->from, n);
		if (err)
			goto Efault;
		m->count -= n;
		m->from += n;
		size -= n;
		buf += n;
		copied += n;
		if (!m->count)
			m->index++;
		if (!size)
			goto Done;
	}
	/* we need at least one record in buffer */
	while (1) {
		pos = m->index;
		p = m->op->start(m, &pos);
		err = PTR_ERR(p);
		if (!p || IS_ERR(p))
			break;
		err = m->op->show(m, p);
		if (err)
			break;
		if (m->count < m->size)
			goto Fill;
		m->op->stop(m, p);
		kfree(m->buf);
		m->buf = kmalloc(m->size <<= 1, GFP_KERNEL);
		if (!m->buf)
			goto Enomem;
		m->count = 0;
		m->version = 0;
	}
	m->op->stop(m, p);
	m->count = 0;
	goto Done;
Fill:
	/* they want more? let's try to get some more */
	while (m->count < size) {
		size_t offs = m->count;
		loff_t next = pos;
		p = m->op->next(m, p, &next);
		if (!p || IS_ERR(p)) {
			err = PTR_ERR(p);
			break;
		}
		err = m->op->show(m, p);
		if (err || m->count == m->size) {
			m->count = offs;
			break;
		}
		pos = next;
	}
	m->op->stop(m, p);
	n = min(m->count, size);
	err = copy_to_user(buf, m->buf, n);
	if (err)
		goto Efault;
	copied += n;
	m->count -= n;
	if (m->count)
		m->from = n;
	else
		pos++;
	m->index = pos;
Done:
	if (!copied)
		copied = err;
	else
		*ppos += copied;
	file->f_version = m->version;
	mutex_unlock(&m->lock);
	return copied;
Enomem:
	err = -ENOMEM;
	goto Done;
Efault:
	err = -EFAULT;
	goto Done;
}
EXPORT_SYMBOL(seq_read);

static int traverse(struct seq_file *m, loff_t offset)
{
	loff_t pos = 0;
	int error = 0;
	void *p;

	m->version = 0;
	m->index = 0;
	m->count = m->from = 0;
	if (!offset)
		return 0;
	if (!m->buf) {
		m->buf = kmalloc(m->size = PAGE_SIZE, GFP_KERNEL);
		if (!m->buf)
			return -ENOMEM;
	}
	p = m->op->start(m, &m->index);
	while (p) {
		error = PTR_ERR(p);
		if (IS_ERR(p))
			break;
		error = m->op->show(m, p);
		if (error)
			break;
		if (m->count == m->size)
			goto Eoverflow;
		if (pos + m->count > offset) {
			m->from = offset - pos;
			m->count -= m->from;
			break;
		}
		pos += m->count;
		m->count = 0;
		if (pos == offset) {
			m->index++;
			break;
		}
		p = m->op->next(m, p, &m->index);
	}
	m->op->stop(m, p);
	return error;

Eoverflow:
	m->op->stop(m, p);
	kfree(m->buf);
	m->buf = kmalloc(m->size <<= 1, GFP_KERNEL);
	return !m->buf ? -ENOMEM : -EAGAIN;
}

/**
 *	seq_lseek -	->llseek() method for sequential files.
 *	@file: the file in question
 *	@offset: new position
 *	@origin: 0 for absolute, 1 for relative position
 *
 *	Ready-made ->f_op->llseek()
 */
loff_t seq_lseek(struct file *file, loff_t offset, int origin)
{
	struct seq_file *m = (struct seq_file *)file->private_data;
	long long retval = -EINVAL;

	mutex_lock(&m->lock);
	m->version = file->f_version;
	switch (origin) {
		case 1:
			offset += file->f_pos;
		case 0:
			if (offset < 0)
				break;
			retval = offset;
			if (offset != file->f_pos) {
				while ((retval=traverse(m, offset)) == -EAGAIN)
					;
				if (retval) {
					/* with extreme prejudice... */
					file->f_pos = 0;
					m->version = 0;
					m->index = 0;
					m->count = 0;
				} else {
					retval = file->f_pos = offset;
				}
			}
	}
	mutex_unlock(&m->lock);
	file->f_version = m->version;
	return retval;
}
EXPORT_SYMBOL(seq_lseek);

/**
 *	seq_release -	free the structures associated with sequential file.
 *	@file: file in question
 *	@inode: file->f_dentry->d_inode
 *
 *	Frees the structures associated with sequential file; can be used
 *	as ->f_op->release() if you don't have private data to destroy.
 */
int seq_release(struct inode *inode, struct file *file)
{
	struct seq_file *m = (struct seq_file *)file->private_data;
	kfree(m->buf);
	kfree(m);
	return 0;
}
EXPORT_SYMBOL(seq_release);

/**
 *	seq_escape -	print string into buffer, escaping some characters
 *	@m:	target buffer
 *	@s:	string
 *	@esc:	set of characters that need escaping
 *
 *	Puts string into buffer, replacing each occurrence of character from
 *	@esc with usual octal escape.  Returns 0 in case of success, -1 - in
 *	case of overflow.
 */
int seq_escape(struct seq_file *m, const char *s, const char *esc)
{
	char *end = m->buf + m->size;
        char *p;
	char c;

        for (p = m->buf + m->count; (c = *s) != '\0' && p < end; s++) {
		if (!strchr(esc, c)) {
			*p++ = c;
			continue;
		}
		if (p + 3 < end) {
			*p++ = '\\';
			*p++ = '0' + ((c & 0300) >> 6);
			*p++ = '0' + ((c & 070) >> 3);
			*p++ = '0' + (c & 07);
			continue;
		}
		m->count = m->size;
		return -1;
        }
	m->count = p - m->buf;
        return 0;
}
EXPORT_SYMBOL(seq_escape);

int seq_printf(struct seq_file *m, const char *f, ...)
{
	va_list args;
	int len;

	if (m->count < m->size) {
		va_start(args, f);
		len = vsnprintf(m->buf + m->count, m->size - m->count, f, args);
		va_end(args);
		if (m->count + len < m->size) {
			m->count += len;
			return 0;
		}
	}
	m->count = m->size;
	return -1;
}
EXPORT_SYMBOL(seq_printf);

int seq_path(struct seq_file *m,
	     struct vfsmount *mnt, struct dentry *dentry,
	     char *esc)
{
	if (m->count < m->size) {
		char *s = m->buf + m->count;
		char *p = d_path(dentry, mnt, s, m->size - m->count);
		if (!IS_ERR(p)) {
			while (s <= p) {
				char c = *p++;
				if (!c) {
					p = m->buf + m->count;
					m->count = s - m->buf;
					return s - p;
				} else if (!strchr(esc, c)) {
					*s++ = c;
				} else if (s + 4 > p) {
					break;
				} else {
					*s++ = '\\';
					*s++ = '0' + ((c & 0300) >> 6);
					*s++ = '0' + ((c & 070) >> 3);
					*s++ = '0' + (c & 07);
				}
			}
		}
	}
	m->count = m->size;
	return -1;
}
EXPORT_SYMBOL(seq_path);

static void *single_start(struct seq_file *p, loff_t *pos)
{
	return NULL + (*pos == 0);
}

static void *single_next(struct seq_file *p, void *v, loff_t *pos)
{
	++*pos;
	return NULL;
}

static void single_stop(struct seq_file *p, void *v)
{
}

int single_open(struct file *file, int (*show)(struct seq_file *, void *),
		void *data)
{
	struct seq_operations *op = kmalloc(sizeof(*op), GFP_KERNEL);
	int res = -ENOMEM;

	if (op) {
		op->start = single_start;
		op->next = single_next;
		op->stop = single_stop;
		op->show = show;
		res = seq_open(file, op);
		if (!res)
			((struct seq_file *)file->private_data)->private = data;
		else
			kfree(op);
	}
	return res;
}
EXPORT_SYMBOL(single_open);

int single_release(struct inode *inode, struct file *file)
{
	struct seq_operations *op = ((struct seq_file *)file->private_data)->op;
	int res = seq_release(inode, file);
	kfree(op);
	return res;
}
EXPORT_SYMBOL(single_release);

int seq_release_private(struct inode *inode, struct file *file)
{
	struct seq_file *seq = file->private_data;

	kfree(seq->private);
	seq->private = NULL;
	return seq_release(inode, file);
}
EXPORT_SYMBOL(seq_release_private);

int seq_putc(struct seq_file *m, char c)
{
	if (m->count < m->size) {
		m->buf[m->count++] = c;
		return 0;
	}
	return -1;
}
EXPORT_SYMBOL(seq_putc);

int seq_puts(struct seq_file *m, const char *s)
{
	int len = strlen(s);
	if (m->count + len < m->size) {
		memcpy(m->buf + m->count, s, len);
		m->count += len;
		return 0;
	}
	m->count = m->size;
	return -1;
}
EXPORT_SYMBOL(seq_puts);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/seq_file.c
	3	*
	4	* helper functions for making synthetic files from sequences of records.
	5	* initial implementation -- AV, Oct 2001.
	6	*/
	7
	8	#include <linux/fs.h>
	9	#include <linux/module.h>
	10	#include <linux/seq_file.h>
	11	#include <linux/slab.h>
	12
	13	#include <asm/uaccess.h>
	14	#include <asm/page.h>
	15
	16	/**
	17	* seq_open - initialize sequential file
	18	* @file: file we initialize
	19	* @op: method table describing the sequence
	20	*
	21	* seq_open() sets @file, associating it with a sequence described
	22	* by @op. @op->start() sets the iterator up and returns the first
	23	* element of sequence. @op->stop() shuts it down. @op->next()
	24	* returns the next element of sequence. @op->show() prints element
	25	* into the buffer. In case of error ->start() and ->next() return
	26	* ERR_PTR(error). In the end of sequence they return %NULL. ->show()
	27	* returns 0 in case of success and negative number in case of error.
	28	*/
	29	int seq_open(struct file file, struct seq_operations op)
	30	{
1abe77b0 AV	31	struct seq_file *p = file->private_data;
	32
	33	if (!p) {
	34	p = kmalloc(sizeof(*p), GFP_KERNEL);
	35	if (!p)
	36	return -ENOMEM;
	37	file->private_data = p;
	38	}
1da177e4	39	memset(p, 0, sizeof(*p));
0ac1759a	40	mutex_init(&p->lock);
1da177e4	41	p->op = op;
1da177e4 LT	42
	43	/*
	44	* Wrappers around seq_open(e.g. swaps_open) need to be
	45	* aware of this. If they set f_version themselves, they
	46	* should call seq_open first and then set f_version.
	47	*/
	48	file->f_version = 0;
	49
	50	/* SEQ files support lseek, but not pread/pwrite */
	51	file->f_mode &= ~(FMODE_PREAD \| FMODE_PWRITE);
	52	return 0;
	53	}
	54	EXPORT_SYMBOL(seq_open);
	55
	56	/**
	57	* seq_read - ->read() method for sequential files.
67be2dd1 MW	58	* @file: the file to read from
	59	* @buf: the buffer to read to
	60	* @size: the maximum number of bytes to read
	61	* @ppos: the current position in the file
1da177e4 LT	62	*
	63	* Ready-made ->f_op->read()
	64	*/
	65	ssize_t seq_read(struct file file, char __user buf, size_t size, loff_t *ppos)
	66	{
	67	struct seq_file m = (struct seq_file )file->private_data;
	68	size_t copied = 0;
	69	loff_t pos;
	70	size_t n;
	71	void *p;
	72	int err = 0;
	73
0ac1759a	74	mutex_lock(&m->lock);
1da177e4 LT	75	/*
	76	* seq_file->op->..m_start/m_stop/m_next may do special actions
	77	* or optimisations based on the file->f_version, so we want to
	78	* pass the file->f_version to those methods.
	79	*
	80	* seq_file->version is just copy of f_version, and seq_file
	81	* methods can treat it simply as file version.
	82	* It is copied in first and copied out after all operations.
	83	* It is convenient to have it as part of structure to avoid the
	84	* need of passing another argument to all the seq_file methods.
	85	*/
	86	m->version = file->f_version;
	87	/* grab buffer if we didn't have one */
	88	if (!m->buf) {
	89	m->buf = kmalloc(m->size = PAGE_SIZE, GFP_KERNEL);
	90	if (!m->buf)
	91	goto Enomem;
	92	}
	93	/* if not empty - flush it first */
	94	if (m->count) {
	95	n = min(m->count, size);
	96	err = copy_to_user(buf, m->buf + m->from, n);
	97	if (err)
	98	goto Efault;
	99	m->count -= n;
	100	m->from += n;
	101	size -= n;
	102	buf += n;
	103	copied += n;
	104	if (!m->count)
	105	m->index++;
	106	if (!size)
	107	goto Done;
	108	}
	109	/* we need at least one record in buffer */
	110	while (1) {
	111	pos = m->index;
	112	p = m->op->start(m, &pos);
	113	err = PTR_ERR(p);
	114	if (!p \|\| IS_ERR(p))
	115	break;
	116	err = m->op->show(m, p);
	117	if (err)
	118	break;
	119	if (m->count < m->size)
	120	goto Fill;
	121	m->op->stop(m, p);
	122	kfree(m->buf);
	123	m->buf = kmalloc(m->size <<= 1, GFP_KERNEL);
	124	if (!m->buf)
	125	goto Enomem;
	126	m->count = 0;
	127	m->version = 0;
	128	}
	129	m->op->stop(m, p);
	130	m->count = 0;
	131	goto Done;
	132	Fill:
	133	/* they want more? let's try to get some more */
	134	while (m->count < size) {
	135	size_t offs = m->count;
	136	loff_t next = pos;
	137	p = m->op->next(m, p, &next);
	138	if (!p \|\| IS_ERR(p)) {
139	err = PTR_ERR(p);
140	break;
141	}
142	err = m->op->show(m, p);
143	if (err \|\| m->count == m->size) {
144	m->count = offs;
145	break;
146	}
147	pos = next;
148	}
149	m->op->stop(m, p);
150	n = min(m->count, size);
151	err = copy_to_user(buf, m->buf, n);
152	if (err)
153	goto Efault;
154	copied += n;
155	m->count -= n;
156	if (m->count)
157	m->from = n;
158	else
159	pos++;
160	m->index = pos;
161	Done:
162	if (!copied)
163	copied = err;
164	else
165	*ppos += copied;
166	file->f_version = m->version;
0ac1759a	167	mutex_unlock(&m->lock);
1da177e4 LT	168	return copied;
	169	Enomem:
	170	err = -ENOMEM;
	171	goto Done;
	172	Efault:
	173	err = -EFAULT;
	174	goto Done;
	175	}
	176	EXPORT_SYMBOL(seq_read);
	177
	178	static int traverse(struct seq_file *m, loff_t offset)
	179	{
	180	loff_t pos = 0;
	181	int error = 0;
	182	void *p;
	183
	184	m->version = 0;
	185	m->index = 0;
	186	m->count = m->from = 0;
	187	if (!offset)
	188	return 0;
	189	if (!m->buf) {
	190	m->buf = kmalloc(m->size = PAGE_SIZE, GFP_KERNEL);
	191	if (!m->buf)
	192	return -ENOMEM;
	193	}
	194	p = m->op->start(m, &m->index);
	195	while (p) {
	196	error = PTR_ERR(p);
	197	if (IS_ERR(p))
	198	break;
	199	error = m->op->show(m, p);
	200	if (error)
	201	break;
	202	if (m->count == m->size)
	203	goto Eoverflow;
	204	if (pos + m->count > offset) {
	205	m->from = offset - pos;
	206	m->count -= m->from;
	207	break;
	208	}
	209	pos += m->count;
	210	m->count = 0;
	211	if (pos == offset) {
	212	m->index++;
	213	break;
	214	}
	215	p = m->op->next(m, p, &m->index);
	216	}
	217	m->op->stop(m, p);
	218	return error;
	219
	220	Eoverflow:
	221	m->op->stop(m, p);
	222	kfree(m->buf);
	223	m->buf = kmalloc(m->size <<= 1, GFP_KERNEL);
	224	return !m->buf ? -ENOMEM : -EAGAIN;
	225	}
	226
	227	/**
	228	* seq_lseek - ->llseek() method for sequential files.
67be2dd1 MW	229	* @file: the file in question
	230	* @offset: new position
	231	* @origin: 0 for absolute, 1 for relative position
1da177e4 LT	232	*
	233	* Ready-made ->f_op->llseek()
	234	*/
	235	loff_t seq_lseek(struct file *file, loff_t offset, int origin)
	236	{
	237	struct seq_file m = (struct seq_file )file->private_data;
	238	long long retval = -EINVAL;
	239
0ac1759a	240	mutex_lock(&m->lock);
1da177e4 LT	241	m->version = file->f_version;
	242	switch (origin) {
	243	case 1:
	244	offset += file->f_pos;
	245	case 0:
	246	if (offset < 0)
	247	break;
	248	retval = offset;
	249	if (offset != file->f_pos) {
	250	while ((retval=traverse(m, offset)) == -EAGAIN)
	251	;
	252	if (retval) {
	253	/* with extreme prejudice... */
	254	file->f_pos = 0;
	255	m->version = 0;
	256	m->index = 0;
	257	m->count = 0;
	258	} else {
	259	retval = file->f_pos = offset;
	260	}
	261	}
	262	}
0ac1759a	263	mutex_unlock(&m->lock);
1da177e4 LT	264	file->f_version = m->version;
	265	return retval;
	266	}
	267	EXPORT_SYMBOL(seq_lseek);
	268
	269	/**
	270	* seq_release - free the structures associated with sequential file.
	271	* @file: file in question
	272	* @inode: file->f_dentry->d_inode
	273	*
	274	* Frees the structures associated with sequential file; can be used
	275	* as ->f_op->release() if you don't have private data to destroy.
	276	*/
	277	int seq_release(struct inode inode, struct file file)
	278	{
	279	struct seq_file m = (struct seq_file )file->private_data;
	280	kfree(m->buf);
	281	kfree(m);
	282	return 0;
	283	}
	284	EXPORT_SYMBOL(seq_release);
	285
	286	/**
	287	* seq_escape - print string into buffer, escaping some characters
	288	* @m: target buffer
	289	* @s: string
	290	* @esc: set of characters that need escaping
	291	*
	292	* Puts string into buffer, replacing each occurrence of character from
	293	* @esc with usual octal escape. Returns 0 in case of success, -1 - in
	294	* case of overflow.
	295	*/
	296	int seq_escape(struct seq_file m, const char s, const char *esc)
	297	{
	298	char *end = m->buf + m->size;
	299	char *p;
	300	char c;
	301
	302	for (p = m->buf + m->count; (c = *s) != '\0' && p < end; s++) {
	303	if (!strchr(esc, c)) {
	304	*p++ = c;
	305	continue;
	306	}
	307	if (p + 3 < end) {
	308	*p++ = '\\';
	309	*p++ = '0' + ((c & 0300) >> 6);
	310	*p++ = '0' + ((c & 070) >> 3);
	311	*p++ = '0' + (c & 07);
	312	continue;
	313	}
	314	m->count = m->size;
	315	return -1;
	316	}
	317	m->count = p - m->buf;
	318	return 0;
	319	}
	320	EXPORT_SYMBOL(seq_escape);
	321
	322	int seq_printf(struct seq_file m, const char f, ...)
	323	{
	324	va_list args;
	325	int len;
	326
	327	if (m->count < m->size) {
328	va_start(args, f);
329	len = vsnprintf(m->buf + m->count, m->size - m->count, f, args);
330	va_end(args);
331	if (m->count + len < m->size) {
332	m->count += len;
333	return 0;
334	}
335	}
336	m->count = m->size;
337	return -1;
338	}
339	EXPORT_SYMBOL(seq_printf);
340
341	int seq_path(struct seq_file *m,
342	struct vfsmount mnt, struct dentry dentry,
343	char *esc)
344	{
345	if (m->count < m->size) {
346	char *s = m->buf + m->count;
347	char *p = d_path(dentry, mnt, s, m->size - m->count);
348	if (!IS_ERR(p)) {
349	while (s <= p) {
350	char c = *p++;
351	if (!c) {
352	p = m->buf + m->count;
353	m->count = s - m->buf;
354	return s - p;
355	} else if (!strchr(esc, c)) {
356	*s++ = c;
357	} else if (s + 4 > p) {
358	break;
359	} else {
360	*s++ = '\\';
361	*s++ = '0' + ((c & 0300) >> 6);
362	*s++ = '0' + ((c & 070) >> 3);
363	*s++ = '0' + (c & 07);
364	}
365	}
366	}
367	}
368	m->count = m->size;
369	return -1;
370	}
371	EXPORT_SYMBOL(seq_path);
372
373	static void single_start(struct seq_file p, loff_t *pos)
374	{
375	return NULL + (*pos == 0);
376	}
377
378	static void single_next(struct seq_file p, void v, loff_t pos)
379	{
380	++*pos;
381	return NULL;
382	}
383
384	static void single_stop(struct seq_file p, void v)
385	{
386	}
387
388	int single_open(struct file file, int (show)(struct seq_file , void ),
389	void *data)
390	{
391	struct seq_operations op = kmalloc(sizeof(op), GFP_KERNEL);
392	int res = -ENOMEM;
393
394	if (op) {
395	op->start = single_start;
396	op->next = single_next;
397	op->stop = single_stop;
398	op->show = show;
399	res = seq_open(file, op);
400	if (!res)
401	((struct seq_file *)file->private_data)->private = data;
402	else
403	kfree(op);
404	}
405	return res;
406	}
407	EXPORT_SYMBOL(single_open);
408
409	int single_release(struct inode inode, struct file file)
410	{
411	struct seq_operations op = ((struct seq_file )file->private_data)->op;
412	int res = seq_release(inode, file);
413	kfree(op);
414	return res;
415	}
416	EXPORT_SYMBOL(single_release);
417
418	int seq_release_private(struct inode inode, struct file file)
419	{
420	struct seq_file *seq = file->private_data;
421
422	kfree(seq->private);
423	seq->private = NULL;
424	return seq_release(inode, file);
425	}
426	EXPORT_SYMBOL(seq_release_private);
427
428	int seq_putc(struct seq_file *m, char c)
429	{
430	if (m->count < m->size) {
431	m->buf[m->count++] = c;
432	return 0;
433	}
434	return -1;
435	}
436	EXPORT_SYMBOL(seq_putc);
437
438	int seq_puts(struct seq_file m, const char s)
439	{
440	int len = strlen(s);
441	if (m->count + len < m->size) {
442	memcpy(m->buf + m->count, s, len);
443	m->count += len;
444	return 0;
445	}
446	m->count = m->size;
447	return -1;
448	}
449	EXPORT_SYMBOL(seq_puts);