xref: /openbmc/linux/include/linux/seq_file.h (revision 171f1bc7)
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/mutex.h>
7 #include <linux/cpumask.h>
8 #include <linux/nodemask.h>
9 
10 struct seq_operations;
11 struct file;
12 struct path;
13 struct inode;
14 struct dentry;
15 
16 struct seq_file {
17 	char *buf;
18 	size_t size;
19 	size_t from;
20 	size_t count;
21 	loff_t index;
22 	loff_t read_pos;
23 	u64 version;
24 	struct mutex lock;
25 	const struct seq_operations *op;
26 	int poll_event;
27 	void *private;
28 };
29 
30 struct seq_operations {
31 	void * (*start) (struct seq_file *m, loff_t *pos);
32 	void (*stop) (struct seq_file *m, void *v);
33 	void * (*next) (struct seq_file *m, void *v, loff_t *pos);
34 	int (*show) (struct seq_file *m, void *v);
35 };
36 
37 #define SEQ_SKIP 1
38 
39 /**
40  * seq_get_buf - get buffer to write arbitrary data to
41  * @m: the seq_file handle
42  * @bufp: the beginning of the buffer is stored here
43  *
44  * Return the number of bytes available in the buffer, or zero if
45  * there's no space.
46  */
47 static inline size_t seq_get_buf(struct seq_file *m, char **bufp)
48 {
49 	BUG_ON(m->count > m->size);
50 	if (m->count < m->size)
51 		*bufp = m->buf + m->count;
52 	else
53 		*bufp = NULL;
54 
55 	return m->size - m->count;
56 }
57 
58 /**
59  * seq_commit - commit data to the buffer
60  * @m: the seq_file handle
61  * @num: the number of bytes to commit
62  *
63  * Commit @num bytes of data written to a buffer previously acquired
64  * by seq_buf_get.  To signal an error condition, or that the data
65  * didn't fit in the available space, pass a negative @num value.
66  */
67 static inline void seq_commit(struct seq_file *m, int num)
68 {
69 	if (num < 0) {
70 		m->count = m->size;
71 	} else {
72 		BUG_ON(m->count + num > m->size);
73 		m->count += num;
74 	}
75 }
76 
77 char *mangle_path(char *s, char *p, char *esc);
78 int seq_open(struct file *, const struct seq_operations *);
79 ssize_t seq_read(struct file *, char __user *, size_t, loff_t *);
80 loff_t seq_lseek(struct file *, loff_t, int);
81 int seq_release(struct inode *, struct file *);
82 int seq_escape(struct seq_file *, const char *, const char *);
83 int seq_putc(struct seq_file *m, char c);
84 int seq_puts(struct seq_file *m, const char *s);
85 int seq_write(struct seq_file *seq, const void *data, size_t len);
86 
87 __printf(2, 3) int seq_printf(struct seq_file *, const char *, ...);
88 
89 int seq_path(struct seq_file *, struct path *, char *);
90 int seq_dentry(struct seq_file *, struct dentry *, char *);
91 int seq_path_root(struct seq_file *m, struct path *path, struct path *root,
92 		  char *esc);
93 int seq_bitmap(struct seq_file *m, const unsigned long *bits,
94 				   unsigned int nr_bits);
95 static inline int seq_cpumask(struct seq_file *m, const struct cpumask *mask)
96 {
97 	return seq_bitmap(m, cpumask_bits(mask), nr_cpu_ids);
98 }
99 
100 static inline int seq_nodemask(struct seq_file *m, nodemask_t *mask)
101 {
102 	return seq_bitmap(m, mask->bits, MAX_NUMNODES);
103 }
104 
105 int seq_bitmap_list(struct seq_file *m, const unsigned long *bits,
106 		unsigned int nr_bits);
107 
108 static inline int seq_cpumask_list(struct seq_file *m,
109 				   const struct cpumask *mask)
110 {
111 	return seq_bitmap_list(m, cpumask_bits(mask), nr_cpu_ids);
112 }
113 
114 static inline int seq_nodemask_list(struct seq_file *m, nodemask_t *mask)
115 {
116 	return seq_bitmap_list(m, mask->bits, MAX_NUMNODES);
117 }
118 
119 int single_open(struct file *, int (*)(struct seq_file *, void *), void *);
120 int single_release(struct inode *, struct file *);
121 void *__seq_open_private(struct file *, const struct seq_operations *, int);
122 int seq_open_private(struct file *, const struct seq_operations *, int);
123 int seq_release_private(struct inode *, struct file *);
124 
125 #define SEQ_START_TOKEN ((void *)1)
126 
127 /*
128  * Helpers for iteration over list_head-s in seq_files
129  */
130 
131 extern struct list_head *seq_list_start(struct list_head *head,
132 		loff_t pos);
133 extern struct list_head *seq_list_start_head(struct list_head *head,
134 		loff_t pos);
135 extern struct list_head *seq_list_next(void *v, struct list_head *head,
136 		loff_t *ppos);
137 
138 /*
139  * Helpers for iteration over hlist_head-s in seq_files
140  */
141 
142 extern struct hlist_node *seq_hlist_start(struct hlist_head *head,
143 					  loff_t pos);
144 extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head,
145 					       loff_t pos);
146 extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
147 					 loff_t *ppos);
148 
149 extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head,
150 					      loff_t pos);
151 extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
152 						   loff_t pos);
153 extern struct hlist_node *seq_hlist_next_rcu(void *v,
154 						   struct hlist_head *head,
155 						   loff_t *ppos);
156 #endif
157