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 struct user_namespace; 17 18 struct seq_file { 19 char *buf; 20 size_t size; 21 size_t from; 22 size_t count; 23 size_t pad_until; 24 loff_t index; 25 loff_t read_pos; 26 u64 version; 27 struct mutex lock; 28 const struct seq_operations *op; 29 int poll_event; 30 #ifdef CONFIG_USER_NS 31 struct user_namespace *user_ns; 32 #endif 33 void *private; 34 }; 35 36 struct seq_operations { 37 void * (*start) (struct seq_file *m, loff_t *pos); 38 void (*stop) (struct seq_file *m, void *v); 39 void * (*next) (struct seq_file *m, void *v, loff_t *pos); 40 int (*show) (struct seq_file *m, void *v); 41 }; 42 43 #define SEQ_SKIP 1 44 45 /** 46 * seq_get_buf - get buffer to write arbitrary data to 47 * @m: the seq_file handle 48 * @bufp: the beginning of the buffer is stored here 49 * 50 * Return the number of bytes available in the buffer, or zero if 51 * there's no space. 52 */ 53 static inline size_t seq_get_buf(struct seq_file *m, char **bufp) 54 { 55 BUG_ON(m->count > m->size); 56 if (m->count < m->size) 57 *bufp = m->buf + m->count; 58 else 59 *bufp = NULL; 60 61 return m->size - m->count; 62 } 63 64 /** 65 * seq_commit - commit data to the buffer 66 * @m: the seq_file handle 67 * @num: the number of bytes to commit 68 * 69 * Commit @num bytes of data written to a buffer previously acquired 70 * by seq_buf_get. To signal an error condition, or that the data 71 * didn't fit in the available space, pass a negative @num value. 72 */ 73 static inline void seq_commit(struct seq_file *m, int num) 74 { 75 if (num < 0) { 76 m->count = m->size; 77 } else { 78 BUG_ON(m->count + num > m->size); 79 m->count += num; 80 } 81 } 82 83 /** 84 * seq_setwidth - set padding width 85 * @m: the seq_file handle 86 * @size: the max number of bytes to pad. 87 * 88 * Call seq_setwidth() for setting max width, then call seq_printf() etc. and 89 * finally call seq_pad() to pad the remaining bytes. 90 */ 91 static inline void seq_setwidth(struct seq_file *m, size_t size) 92 { 93 m->pad_until = m->count + size; 94 } 95 void seq_pad(struct seq_file *m, char c); 96 97 char *mangle_path(char *s, const char *p, const char *esc); 98 int seq_open(struct file *, const struct seq_operations *); 99 ssize_t seq_read(struct file *, char __user *, size_t, loff_t *); 100 loff_t seq_lseek(struct file *, loff_t, int); 101 int seq_release(struct inode *, struct file *); 102 int seq_escape(struct seq_file *, const char *, const char *); 103 int seq_putc(struct seq_file *m, char c); 104 int seq_puts(struct seq_file *m, const char *s); 105 int seq_write(struct seq_file *seq, const void *data, size_t len); 106 107 __printf(2, 3) int seq_printf(struct seq_file *, const char *, ...); 108 __printf(2, 0) int seq_vprintf(struct seq_file *, const char *, va_list args); 109 110 int seq_path(struct seq_file *, const struct path *, const char *); 111 int seq_dentry(struct seq_file *, struct dentry *, const char *); 112 int seq_path_root(struct seq_file *m, const struct path *path, 113 const struct path *root, const char *esc); 114 int seq_bitmap(struct seq_file *m, const unsigned long *bits, 115 unsigned int nr_bits); 116 static inline int seq_cpumask(struct seq_file *m, const struct cpumask *mask) 117 { 118 return seq_bitmap(m, cpumask_bits(mask), nr_cpu_ids); 119 } 120 121 static inline int seq_nodemask(struct seq_file *m, nodemask_t *mask) 122 { 123 return seq_bitmap(m, mask->bits, MAX_NUMNODES); 124 } 125 126 int seq_bitmap_list(struct seq_file *m, const unsigned long *bits, 127 unsigned int nr_bits); 128 129 static inline int seq_cpumask_list(struct seq_file *m, 130 const struct cpumask *mask) 131 { 132 return seq_bitmap_list(m, cpumask_bits(mask), nr_cpu_ids); 133 } 134 135 static inline int seq_nodemask_list(struct seq_file *m, nodemask_t *mask) 136 { 137 return seq_bitmap_list(m, mask->bits, MAX_NUMNODES); 138 } 139 140 int single_open(struct file *, int (*)(struct seq_file *, void *), void *); 141 int single_open_size(struct file *, int (*)(struct seq_file *, void *), void *, size_t); 142 int single_release(struct inode *, struct file *); 143 void *__seq_open_private(struct file *, const struct seq_operations *, int); 144 int seq_open_private(struct file *, const struct seq_operations *, int); 145 int seq_release_private(struct inode *, struct file *); 146 int seq_put_decimal_ull(struct seq_file *m, char delimiter, 147 unsigned long long num); 148 int seq_put_decimal_ll(struct seq_file *m, char delimiter, 149 long long num); 150 151 static inline struct user_namespace *seq_user_ns(struct seq_file *seq) 152 { 153 #ifdef CONFIG_USER_NS 154 return seq->user_ns; 155 #else 156 extern struct user_namespace init_user_ns; 157 return &init_user_ns; 158 #endif 159 } 160 161 #define SEQ_START_TOKEN ((void *)1) 162 /* 163 * Helpers for iteration over list_head-s in seq_files 164 */ 165 166 extern struct list_head *seq_list_start(struct list_head *head, 167 loff_t pos); 168 extern struct list_head *seq_list_start_head(struct list_head *head, 169 loff_t pos); 170 extern struct list_head *seq_list_next(void *v, struct list_head *head, 171 loff_t *ppos); 172 173 /* 174 * Helpers for iteration over hlist_head-s in seq_files 175 */ 176 177 extern struct hlist_node *seq_hlist_start(struct hlist_head *head, 178 loff_t pos); 179 extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head, 180 loff_t pos); 181 extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head, 182 loff_t *ppos); 183 184 extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head, 185 loff_t pos); 186 extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head, 187 loff_t pos); 188 extern struct hlist_node *seq_hlist_next_rcu(void *v, 189 struct hlist_head *head, 190 loff_t *ppos); 191 192 /* Helpers for iterating over per-cpu hlist_head-s in seq_files */ 193 extern struct hlist_node *seq_hlist_start_percpu(struct hlist_head __percpu *head, int *cpu, loff_t pos); 194 195 extern struct hlist_node *seq_hlist_next_percpu(void *v, struct hlist_head __percpu *head, int *cpu, loff_t *pos); 196 197 #endif 198