xref: /openbmc/linux/include/linux/seq_file.h (revision 95e9fd10)
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 
11 struct seq_operations;
12 struct file;
13 struct path;
14 struct inode;
15 struct dentry;
16 
17 struct 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 
31 struct 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  */
48 static 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  */
68 static 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 
78 char *mangle_path(char *s, const char *p, const char *esc);
79 int seq_open(struct file *, const struct seq_operations *);
80 ssize_t seq_read(struct file *, char __user *, size_t, loff_t *);
81 loff_t seq_lseek(struct file *, loff_t, int);
82 int seq_release(struct inode *, struct file *);
83 int seq_escape(struct seq_file *, const char *, const char *);
84 int seq_putc(struct seq_file *m, char c);
85 int seq_puts(struct seq_file *m, const char *s);
86 int 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 __printf(2, 0) int seq_vprintf(struct seq_file *, const char *, va_list args);
90 
91 int seq_path(struct seq_file *, const struct path *, const char *);
92 int seq_dentry(struct seq_file *, struct dentry *, const char *);
93 int seq_path_root(struct seq_file *m, const struct path *path,
94 		  const struct path *root, const char *esc);
95 int seq_bitmap(struct seq_file *m, const unsigned long *bits,
96 				   unsigned int nr_bits);
97 static inline int seq_cpumask(struct seq_file *m, const struct cpumask *mask)
98 {
99 	return seq_bitmap(m, cpumask_bits(mask), nr_cpu_ids);
100 }
101 
102 static inline int seq_nodemask(struct seq_file *m, nodemask_t *mask)
103 {
104 	return seq_bitmap(m, mask->bits, MAX_NUMNODES);
105 }
106 
107 int seq_bitmap_list(struct seq_file *m, const unsigned long *bits,
108 		unsigned int nr_bits);
109 
110 static inline int seq_cpumask_list(struct seq_file *m,
111 				   const struct cpumask *mask)
112 {
113 	return seq_bitmap_list(m, cpumask_bits(mask), nr_cpu_ids);
114 }
115 
116 static inline int seq_nodemask_list(struct seq_file *m, nodemask_t *mask)
117 {
118 	return seq_bitmap_list(m, mask->bits, MAX_NUMNODES);
119 }
120 
121 int single_open(struct file *, int (*)(struct seq_file *, void *), void *);
122 int single_release(struct inode *, struct file *);
123 void *__seq_open_private(struct file *, const struct seq_operations *, int);
124 int seq_open_private(struct file *, const struct seq_operations *, int);
125 int seq_release_private(struct inode *, struct file *);
126 int seq_put_decimal_ull(struct seq_file *m, char delimiter,
127 			unsigned long long num);
128 int seq_put_decimal_ll(struct seq_file *m, char delimiter,
129 			long long num);
130 
131 #define SEQ_START_TOKEN ((void *)1)
132 /*
133  * Helpers for iteration over list_head-s in seq_files
134  */
135 
136 extern struct list_head *seq_list_start(struct list_head *head,
137 		loff_t pos);
138 extern struct list_head *seq_list_start_head(struct list_head *head,
139 		loff_t pos);
140 extern struct list_head *seq_list_next(void *v, struct list_head *head,
141 		loff_t *ppos);
142 
143 /*
144  * Helpers for iteration over hlist_head-s in seq_files
145  */
146 
147 extern struct hlist_node *seq_hlist_start(struct hlist_head *head,
148 					  loff_t pos);
149 extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head,
150 					       loff_t pos);
151 extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
152 					 loff_t *ppos);
153 
154 extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head,
155 					      loff_t pos);
156 extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
157 						   loff_t pos);
158 extern struct hlist_node *seq_hlist_next_rcu(void *v,
159 						   struct hlist_head *head,
160 						   loff_t *ppos);
161 #endif
162