| 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 | #include <linux/fs.h> |
| 11 | #include <linux/cred.h> |
| 12 | |
| 13 | struct seq_operations; |
| 14 | |
| 15 | struct seq_file { |
| 16 | char *buf; |
| 17 | size_t size; |
| 18 | size_t from; |
| 19 | size_t count; |
| 20 | size_t pad_until; |
| 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 | const struct file *file; |
| 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_has_overflowed - check if the buffer has overflowed |
| 42 | * @m: the seq_file handle |
| 43 | * |
| 44 | * seq_files have a buffer which may overflow. When this happens a larger |
| 45 | * buffer is reallocated and all the data will be printed again. |
| 46 | * The overflow state is true when m->count == m->size. |
| 47 | * |
| 48 | * Returns true if the buffer received more than it can hold. |
| 49 | */ |
| 50 | static inline bool seq_has_overflowed(struct seq_file *m) |
| 51 | { |
| 52 | return m->count == m->size; |
| 53 | } |
| 54 | |
| 55 | /** |
| 56 | * seq_get_buf - get buffer to write arbitrary data to |
| 57 | * @m: the seq_file handle |
| 58 | * @bufp: the beginning of the buffer is stored here |
| 59 | * |
| 60 | * Return the number of bytes available in the buffer, or zero if |
| 61 | * there's no space. |
| 62 | */ |
| 63 | static inline size_t seq_get_buf(struct seq_file *m, char **bufp) |
| 64 | { |
| 65 | BUG_ON(m->count > m->size); |
| 66 | if (m->count < m->size) |
| 67 | *bufp = m->buf + m->count; |
| 68 | else |
| 69 | *bufp = NULL; |
| 70 | |
| 71 | return m->size - m->count; |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * seq_commit - commit data to the buffer |
| 76 | * @m: the seq_file handle |
| 77 | * @num: the number of bytes to commit |
| 78 | * |
| 79 | * Commit @num bytes of data written to a buffer previously acquired |
| 80 | * by seq_buf_get. To signal an error condition, or that the data |
| 81 | * didn't fit in the available space, pass a negative @num value. |
| 82 | */ |
| 83 | static inline void seq_commit(struct seq_file *m, int num) |
| 84 | { |
| 85 | if (num < 0) { |
| 86 | m->count = m->size; |
| 87 | } else { |
| 88 | BUG_ON(m->count + num > m->size); |
| 89 | m->count += num; |
| 90 | } |
| 91 | } |
| 92 | |
| 93 | /** |
| 94 | * seq_setwidth - set padding width |
| 95 | * @m: the seq_file handle |
| 96 | * @size: the max number of bytes to pad. |
| 97 | * |
| 98 | * Call seq_setwidth() for setting max width, then call seq_printf() etc. and |
| 99 | * finally call seq_pad() to pad the remaining bytes. |
| 100 | */ |
| 101 | static inline void seq_setwidth(struct seq_file *m, size_t size) |
| 102 | { |
| 103 | m->pad_until = m->count + size; |
| 104 | } |
| 105 | void seq_pad(struct seq_file *m, char c); |
| 106 | |
| 107 | char *mangle_path(char *s, const char *p, const char *esc); |
| 108 | int seq_open(struct file *, const struct seq_operations *); |
| 109 | ssize_t seq_read(struct file *, char __user *, size_t, loff_t *); |
| 110 | loff_t seq_lseek(struct file *, loff_t, int); |
| 111 | int seq_release(struct inode *, struct file *); |
| 112 | int seq_write(struct seq_file *seq, const void *data, size_t len); |
| 113 | |
| 114 | __printf(2, 0) |
| 115 | void seq_vprintf(struct seq_file *m, const char *fmt, va_list args); |
| 116 | __printf(2, 3) |
| 117 | void seq_printf(struct seq_file *m, const char *fmt, ...); |
| 118 | void seq_putc(struct seq_file *m, char c); |
| 119 | void seq_puts(struct seq_file *m, const char *s); |
| 120 | void seq_put_decimal_ull(struct seq_file *m, const char *delimiter, |
| 121 | unsigned long long num); |
| 122 | void seq_put_decimal_ll(struct seq_file *m, const char *delimiter, long long num); |
| 123 | void seq_escape(struct seq_file *m, const char *s, const char *esc); |
| 124 | |
| 125 | void seq_hex_dump(struct seq_file *m, const char *prefix_str, int prefix_type, |
| 126 | int rowsize, int groupsize, const void *buf, size_t len, |
| 127 | bool ascii); |
| 128 | |
| 129 | int seq_path(struct seq_file *, const struct path *, const char *); |
| 130 | int seq_file_path(struct seq_file *, struct file *, const char *); |
| 131 | int seq_dentry(struct seq_file *, struct dentry *, const char *); |
| 132 | int seq_path_root(struct seq_file *m, const struct path *path, |
| 133 | const struct path *root, const char *esc); |
| 134 | |
| 135 | int single_open(struct file *, int (*)(struct seq_file *, void *), void *); |
| 136 | int single_open_size(struct file *, int (*)(struct seq_file *, void *), void *, size_t); |
| 137 | int single_release(struct inode *, struct file *); |
| 138 | void *__seq_open_private(struct file *, const struct seq_operations *, int); |
| 139 | int seq_open_private(struct file *, const struct seq_operations *, int); |
| 140 | int seq_release_private(struct inode *, struct file *); |
| 141 | |
| 142 | static inline struct user_namespace *seq_user_ns(struct seq_file *seq) |
| 143 | { |
| 144 | #ifdef CONFIG_USER_NS |
| 145 | return seq->file->f_cred->user_ns; |
| 146 | #else |
| 147 | extern struct user_namespace init_user_ns; |
| 148 | return &init_user_ns; |
| 149 | #endif |
| 150 | } |
| 151 | |
| 152 | /** |
| 153 | * seq_show_options - display mount options with appropriate escapes. |
| 154 | * @m: the seq_file handle |
| 155 | * @name: the mount option name |
| 156 | * @value: the mount option name's value, can be NULL |
| 157 | */ |
| 158 | static inline void seq_show_option(struct seq_file *m, const char *name, |
| 159 | const char *value) |
| 160 | { |
| 161 | seq_putc(m, ','); |
| 162 | seq_escape(m, name, ",= \t\n\\"); |
| 163 | if (value) { |
| 164 | seq_putc(m, '='); |
| 165 | seq_escape(m, value, ", \t\n\\"); |
| 166 | } |
| 167 | } |
| 168 | |
| 169 | /** |
| 170 | * seq_show_option_n - display mount options with appropriate escapes |
| 171 | * where @value must be a specific length. |
| 172 | * @m: the seq_file handle |
| 173 | * @name: the mount option name |
| 174 | * @value: the mount option name's value, cannot be NULL |
| 175 | * @length: the length of @value to display |
| 176 | * |
| 177 | * This is a macro since this uses "length" to define the size of the |
| 178 | * stack buffer. |
| 179 | */ |
| 180 | #define seq_show_option_n(m, name, value, length) { \ |
| 181 | char val_buf[length + 1]; \ |
| 182 | strncpy(val_buf, value, length); \ |
| 183 | val_buf[length] = '\0'; \ |
| 184 | seq_show_option(m, name, val_buf); \ |
| 185 | } |
| 186 | |
| 187 | #define SEQ_START_TOKEN ((void *)1) |
| 188 | /* |
| 189 | * Helpers for iteration over list_head-s in seq_files |
| 190 | */ |
| 191 | |
| 192 | extern struct list_head *seq_list_start(struct list_head *head, |
| 193 | loff_t pos); |
| 194 | extern struct list_head *seq_list_start_head(struct list_head *head, |
| 195 | loff_t pos); |
| 196 | extern struct list_head *seq_list_next(void *v, struct list_head *head, |
| 197 | loff_t *ppos); |
| 198 | |
| 199 | /* |
| 200 | * Helpers for iteration over hlist_head-s in seq_files |
| 201 | */ |
| 202 | |
| 203 | extern struct hlist_node *seq_hlist_start(struct hlist_head *head, |
| 204 | loff_t pos); |
| 205 | extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head, |
| 206 | loff_t pos); |
| 207 | extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head, |
| 208 | loff_t *ppos); |
| 209 | |
| 210 | extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head, |
| 211 | loff_t pos); |
| 212 | extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head, |
| 213 | loff_t pos); |
| 214 | extern struct hlist_node *seq_hlist_next_rcu(void *v, |
| 215 | struct hlist_head *head, |
| 216 | loff_t *ppos); |
| 217 | |
| 218 | /* Helpers for iterating over per-cpu hlist_head-s in seq_files */ |
| 219 | extern struct hlist_node *seq_hlist_start_percpu(struct hlist_head __percpu *head, int *cpu, loff_t pos); |
| 220 | |
| 221 | extern struct hlist_node *seq_hlist_next_percpu(void *v, struct hlist_head __percpu *head, int *cpu, loff_t *pos); |
| 222 | |
| 223 | #endif |