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/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 int seq_printf(struct seq_file *, const char *, ...)
  88         __attribute__ ((format (printf,2,3)));
  89
  90 int seq_path(struct seq_file *, struct path *, char *);
  91 int seq_dentry(struct seq_file *, struct dentry *, char *);
  92 int seq_path_root(struct seq_file *m, struct path *path, struct path *root,
  93                   char *esc);
  94 int seq_bitmap(struct seq_file *m, const unsigned long *bits,
  95                                    unsigned int nr_bits);
  96 static 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
 101 static inline int seq_nodemask(struct seq_file *m, nodemask_t *mask)
 102 {
 103         return seq_bitmap(m, mask->bits, MAX_NUMNODES);
 104 }
 105
 106 int seq_bitmap_list(struct seq_file *m, const unsigned long *bits,
 107                 unsigned int nr_bits);
 108
 109 static 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
 115 static 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
 120 int single_open(struct file *, int (*)(struct seq_file *, void *), void *);
 121 int single_release(struct inode *, struct file *);
 122 void *__seq_open_private(struct file *, const struct seq_operations *, int);
 123 int seq_open_private(struct file *, const struct seq_operations *, int);
 124 int seq_release_private(struct inode *, struct file *);
 125
 126 #define SEQ_START_TOKEN ((void *)1)
 127
 128 /*
 129  * Helpers for iteration over list_head-s in seq_files
 130  */
 131
 132 extern struct list_head *seq_list_start(struct list_head *head,
 133                 loff_t pos);
 134 extern struct list_head *seq_list_start_head(struct list_head *head,
 135                 loff_t pos);
 136 extern struct list_head *seq_list_next(void *v, struct list_head *head,
 137                 loff_t *ppos);
 138
 139 /*
 140  * Helpers for iteration over hlist_head-s in seq_files
 141  */
 142
 143 extern struct hlist_node *seq_hlist_start(struct hlist_head *head,
 144                                           loff_t pos);
 145 extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head,
 146                                                loff_t pos);
 147 extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
 148                                          loff_t *ppos);
 149
 150 extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head,
 151                                               loff_t pos);
 152 extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
 153                                                    loff_t pos);
 154 extern struct hlist_node *seq_hlist_next_rcu(void *v,
 155                                                    struct hlist_head *head,
 156                                                    loff_t *ppos);
 157 #endif