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
  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
  90 int seq_path(struct seq_file *, const struct path *, const char *);
  91 int seq_dentry(struct seq_file *, struct dentry *, const char *);
  92 int seq_path_root(struct seq_file *m, const struct path *path,
  93                   const struct path *root, const 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 int seq_put_decimal_ull(struct seq_file *m, char delimiter,
 126                         unsigned long long num);
 127 int 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
 135 extern struct list_head *seq_list_start(struct list_head *head,
 136                 loff_t pos);
 137 extern struct list_head *seq_list_start_head(struct list_head *head,
 138                 loff_t pos);
 139 extern 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
 146 extern struct hlist_node *seq_hlist_start(struct hlist_head *head,
 147                                           loff_t pos);
 148 extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head,
 149                                                loff_t pos);
 150 extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
 151                                          loff_t *ppos);
 152
 153 extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head,
 154                                               loff_t pos);
 155 extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
 156                                                    loff_t pos);
 157 extern struct hlist_node *seq_hlist_next_rcu(void *v,
 158                                                    struct hlist_head *head,
 159                                                    loff_t *ppos);
 160 #endif