/include/linux/seq_file.h

  1#ifndef _LINUX_SEQ_FILE_H
  2#define _LINUX_SEQ_FILE_H
  3
  4#include <linux/types.h>
  5#include <linux/string.h>
  6#include <linux/bug.h>
  7#include <linux/mutex.h>
  8#include <linux/cpumask.h>
  9#include <linux/nodemask.h>
 10
 11struct seq_operations;
 12struct file;
 13struct path;
 14struct inode;
 15struct dentry;
 16
 17struct seq_file {
 18	char *buf;
 19	size_t size;
 20	size_t from;
 21	size_t count;
 22	loff_t index;
 23	loff_t read_pos;
 24	u64 version;
 25	struct mutex lock;
 26	const struct seq_operations *op;
 27	int poll_event;
 28	void *private;
 29};
 30
 31struct seq_operations {
 32	void * (*start) (struct seq_file *m, loff_t *pos);
 33	void (*stop) (struct seq_file *m, void *v);
 34	void * (*next) (struct seq_file *m, void *v, loff_t *pos);
 35	int (*show) (struct seq_file *m, void *v);
 36};
 37
 38#define SEQ_SKIP 1
 39
 40/**
 41 * seq_get_buf - get buffer to write arbitrary data to
 42 * @m: the seq_file handle
 43 * @bufp: the beginning of the buffer is stored here
 44 *
 45 * Return the number of bytes available in the buffer, or zero if
 46 * there's no space.
 47 */
 48static inline size_t seq_get_buf(struct seq_file *m, char **bufp)
 49{
 50	BUG_ON(m->count > m->size);
 51	if (m->count < m->size)
 52		*bufp = m->buf + m->count;
 53	else
 54		*bufp = NULL;
 55
 56	return m->size - m->count;
 57}
 58
 59/**
 60 * seq_commit - commit data to the buffer
 61 * @m: the seq_file handle
 62 * @num: the number of bytes to commit
 63 *
 64 * Commit @num bytes of data written to a buffer previously acquired
 65 * by seq_buf_get.  To signal an error condition, or that the data
 66 * didn't fit in the available space, pass a negative @num value.
 67 */
 68static inline void seq_commit(struct seq_file *m, int num)
 69{
 70	if (num < 0) {
 71		m->count = m->size;
 72	} else {
 73		BUG_ON(m->count + num > m->size);
 74		m->count += num;
 75	}
 76}
 77
 78char *mangle_path(char *s, const char *p, const char *esc);
 79int seq_open(struct file *, const struct seq_operations *);
 80ssize_t seq_read(struct file *, char __user *, size_t, loff_t *);
 81loff_t seq_lseek(struct file *, loff_t, int);
 82int seq_release(struct inode *, struct file *);
 83int seq_escape(struct seq_file *, const char *, const char *);
 84int seq_putc(struct seq_file *m, char c);
 85int seq_puts(struct seq_file *m, const char *s);
 86int seq_write(struct seq_file *seq, const void *data, size_t len);
 87
 88__printf(2, 3) int seq_printf(struct seq_file *, const char *, ...);
 89
 90int seq_path(struct seq_file *, const struct path *, const char *);
 91int seq_dentry(struct seq_file *, struct dentry *, const char *);
 92int seq_path_root(struct seq_file *m, const struct path *path,
 93		  const struct path *root, const char *esc);
 94int seq_bitmap(struct seq_file *m, const unsigned long *bits,
 95				   unsigned int nr_bits);
 96static inline int seq_cpumask(struct seq_file *m, const struct cpumask *mask)
 97{
 98	return seq_bitmap(m, cpumask_bits(mask), nr_cpu_ids);
 99}
100
101static inline int seq_nodemask(struct seq_file *m, nodemask_t *mask)
102{
103	return seq_bitmap(m, mask->bits, MAX_NUMNODES);
104}
105
106int seq_bitmap_list(struct seq_file *m, const unsigned long *bits,
107		unsigned int nr_bits);
108
109static inline int seq_cpumask_list(struct seq_file *m,
110				   const struct cpumask *mask)
111{
112	return seq_bitmap_list(m, cpumask_bits(mask), nr_cpu_ids);
113}
114
115static inline int seq_nodemask_list(struct seq_file *m, nodemask_t *mask)
116{
117	return seq_bitmap_list(m, mask->bits, MAX_NUMNODES);
118}
119
120int single_open(struct file *, int (*)(struct seq_file *, void *), void *);
121int single_release(struct inode *, struct file *);
122void *__seq_open_private(struct file *, const struct seq_operations *, int);
123int seq_open_private(struct file *, const struct seq_operations *, int);
124int seq_release_private(struct inode *, struct file *);
125int seq_put_decimal_ull(struct seq_file *m, char delimiter,
126			unsigned long long num);
127int seq_put_decimal_ll(struct seq_file *m, char delimiter,
128			long long num);
129
130#define SEQ_START_TOKEN ((void *)1)
131/*
132 * Helpers for iteration over list_head-s in seq_files
133 */
134
135extern struct list_head *seq_list_start(struct list_head *head,
136		loff_t pos);
137extern struct list_head *seq_list_start_head(struct list_head *head,
138		loff_t pos);
139extern struct list_head *seq_list_next(void *v, struct list_head *head,
140		loff_t *ppos);
141
142/*
143 * Helpers for iteration over hlist_head-s in seq_files
144 */
145
146extern struct hlist_node *seq_hlist_start(struct hlist_head *head,
147					  loff_t pos);
148extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head,
149					       loff_t pos);
150extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
151					 loff_t *ppos);
152
153extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head,
154					      loff_t pos);
155extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
156						   loff_t pos);
157extern struct hlist_node *seq_hlist_next_rcu(void *v,
158						   struct hlist_head *head,
159						   loff_t *ppos);
160#endif