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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_SEQ_FILE_H
#define _LINUX_SEQ_FILE_H
#include <linux/types.h>
#include <linux/string.h>
#include <linux/string_helpers.h>
#include <linux/bug.h>
#include <linux/mutex.h>
#include <linux/cpumask.h>
#include <linux/nodemask.h>
#include <linux/fs.h>
#include <linux/cred.h>
struct seq_operations;
struct seq_file {
char *buf;
size_t size;
size_t from;
size_t count;
size_t pad_until;
loff_t index;
loff_t read_pos;
struct mutex lock;
const struct seq_operations *op;
int poll_event;
const struct file *file;
void *private;
};
struct seq_operations {
void * (*start) (struct seq_file *m, loff_t *pos);
void (*stop) (struct seq_file *m, void *v);
void * (*next) (struct seq_file *m, void *v, loff_t *pos);
int (*show) (struct seq_file *m, void *v);
};
#define SEQ_SKIP 1
/**
* seq_has_overflowed - check if the buffer has overflowed
* @m: the seq_file handle
*
* seq_files have a buffer which may overflow. When this happens a larger
* buffer is reallocated and all the data will be printed again.
* The overflow state is true when m->count == m->size.
*
* Returns true if the buffer received more than it can hold.
*/
static inline bool seq_has_overflowed(struct seq_file *m)
{
return m->count == m->size;
}
/**
* seq_get_buf - get buffer to write arbitrary data to
* @m: the seq_file handle
* @bufp: the beginning of the buffer is stored here
*
* Return the number of bytes available in the buffer, or zero if
* there's no space.
*/
static inline size_t seq_get_buf(struct seq_file *m, char **bufp)
{
BUG_ON(m->count > m->size);
if (m->count < m->size)
*bufp = m->buf + m->count;
else
*bufp = NULL;
return m->size - m->count;
}
/**
* seq_commit - commit data to the buffer
* @m: the seq_file handle
* @num: the number of bytes to commit
*
* Commit @num bytes of data written to a buffer previously acquired
* by seq_buf_get. To signal an error condition, or that the data
* didn't fit in the available space, pass a negative @num value.
*/
static inline void seq_commit(struct seq_file *m, int num)
{
if (num < 0) {
m->count = m->size;
} else {
BUG_ON(m->count + num > m->size);
m->count += num;
}
}
/**
* seq_setwidth - set padding width
* @m: the seq_file handle
* @size: the max number of bytes to pad.
*
* Call seq_setwidth() for setting max width, then call seq_printf() etc. and
* finally call seq_pad() to pad the remaining bytes.
*/
static inline void seq_setwidth(struct seq_file *m, size_t size)
{
m->pad_until = m->count + size;
}
void seq_pad(struct seq_file *m, char c);
char *mangle_path(char *s, const char *p, const char *esc);
int seq_open(struct file *, const struct seq_operations *);
ssize_t seq_read(struct file *, char __user *, size_t, loff_t *);
ssize_t seq_read_iter(struct kiocb *iocb, struct iov_iter *iter);
loff_t seq_lseek(struct file *, loff_t, int);
int seq_release(struct inode *, struct file *);
int seq_write(struct seq_file *seq, const void *data, size_t len);
__printf(2, 0)
void seq_vprintf(struct seq_file *m, const char *fmt, va_list args);
__printf(2, 3)
void seq_printf(struct seq_file *m, const char *fmt, ...);
void seq_putc(struct seq_file *m, char c);
void seq_puts(struct seq_file *m, const char *s);
void seq_put_decimal_ull_width(struct seq_file *m, const char *delimiter,
unsigned long long num, unsigned int width);
void seq_put_decimal_ull(struct seq_file *m, const char *delimiter,
unsigned long long num);
void seq_put_decimal_ll(struct seq_file *m, const char *delimiter, long long num);
void seq_put_hex_ll(struct seq_file *m, const char *delimiter,
unsigned long long v, unsigned int width);
void seq_escape_mem(struct seq_file *m, const char *src, size_t len,
unsigned int flags, const char *esc);
static inline void seq_escape_str(struct seq_file *m, const char *src,
unsigned int flags, const char *esc)
{
seq_escape_mem(m, src, strlen(src), flags, esc);
}
/**
* seq_escape - print string into buffer, escaping some characters
* @m: target buffer
* @s: NULL-terminated string
* @esc: set of characters that need escaping
*
* Puts string into buffer, replacing each occurrence of character from
* @esc with usual octal escape.
*
* Use seq_has_overflowed() to check for errors.
*/
static inline void seq_escape(struct seq_file *m, const char *s, const char *esc)
{
seq_escape_str(m, s, ESCAPE_OCTAL, esc);
}
void seq_hex_dump(struct seq_file *m, const char *prefix_str, int prefix_type,
int rowsize, int groupsize, const void *buf, size_t len,
bool ascii);
int seq_path(struct seq_file *, const struct path *, const char *);
int seq_file_path(struct seq_file *, struct file *, const char *);
int seq_dentry(struct seq_file *, struct dentry *, const char *);
int seq_path_root(struct seq_file *m, const struct path *path,
const struct path *root, const char *esc);
void *single_start(struct seq_file *, loff_t *);
int single_open(struct file *, int (*)(struct seq_file *, void *), void *);
int single_open_size(struct file *, int (*)(struct seq_file *, void *), void *, size_t);
int single_release(struct inode *, struct file *);
void *__seq_open_private(struct file *, const struct seq_operations *, int);
int seq_open_private(struct file *, const struct seq_operations *, int);
int seq_release_private(struct inode *, struct file *);
#ifdef CONFIG_BINARY_PRINTF
void seq_bprintf(struct seq_file *m, const char *f, const u32 *binary);
#endif
#define DEFINE_SEQ_ATTRIBUTE(__name) \
static int __name ## _open(struct inode *inode, struct file *file) \
{ \
int ret = seq_open(file, &__name ## _sops); \
if (!ret && inode->i_private) { \
struct seq_file *seq_f = file->private_data; \
seq_f->private = inode->i_private; \
} \
return ret; \
} \
\
static const struct file_operations __name ## _fops = { \
.owner = THIS_MODULE, \
.open = __name ## _open, \
.read = seq_read, \
.llseek = seq_lseek, \
.release = seq_release, \
}
#define DEFINE_SHOW_ATTRIBUTE(__name) \
static int __name ## _open(struct inode *inode, struct file *file) \
{ \
return single_open(file, __name ## _show, inode->i_private); \
} \
\
static const struct file_operations __name ## _fops = { \
.owner = THIS_MODULE, \
.open = __name ## _open, \
.read = seq_read, \
.llseek = seq_lseek, \
.release = single_release, \
}
#define DEFINE_SHOW_STORE_ATTRIBUTE(__name) \
static int __name ## _open(struct inode *inode, struct file *file) \
{ \
return single_open(file, __name ## _show, inode->i_private); \
} \
\
static const struct file_operations __name ## _fops = { \
.owner = THIS_MODULE, \
.open = __name ## _open, \
.read = seq_read, \
.write = __name ## _write, \
.llseek = seq_lseek, \
.release = single_release, \
}
#define DEFINE_PROC_SHOW_ATTRIBUTE(__name) \
static int __name ## _open(struct inode *inode, struct file *file) \
{ \
return single_open(file, __name ## _show, pde_data(inode)); \
} \
\
static const struct proc_ops __name ## _proc_ops = { \
.proc_open = __name ## _open, \
.proc_read = seq_read, \
.proc_lseek = seq_lseek, \
.proc_release = single_release, \
}
static inline struct user_namespace *seq_user_ns(struct seq_file *seq)
{
#ifdef CONFIG_USER_NS
return seq->file->f_cred->user_ns;
#else
extern struct user_namespace init_user_ns;
return &init_user_ns;
#endif
}
/**
* seq_show_options - display mount options with appropriate escapes.
* @m: the seq_file handle
* @name: the mount option name
* @value: the mount option name's value, can be NULL
*/
static inline void seq_show_option(struct seq_file *m, const char *name,
const char *value)
{
seq_putc(m, ',');
seq_escape(m, name, ",= \t\n\\");
if (value) {
seq_putc(m, '=');
seq_escape(m, value, ", \t\n\\");
}
}
/**
* seq_show_option_n - display mount options with appropriate escapes
* where @value must be a specific length (i.e.
* not NUL-terminated).
* @m: the seq_file handle
* @name: the mount option name
* @value: the mount option name's value, cannot be NULL
* @length: the exact length of @value to display, must be constant expression
*
* This is a macro since this uses "length" to define the size of the
* stack buffer.
*/
#define seq_show_option_n(m, name, value, length) { \
char val_buf[length + 1]; \
memcpy(val_buf, value, length); \
val_buf[length] = '\0'; \
seq_show_option(m, name, val_buf); \
}
#define SEQ_START_TOKEN ((void *)1)
/*
* Helpers for iteration over list_head-s in seq_files
*/
extern struct list_head *seq_list_start(struct list_head *head,
loff_t pos);
extern struct list_head *seq_list_start_head(struct list_head *head,
loff_t pos);
extern struct list_head *seq_list_next(void *v, struct list_head *head,
loff_t *ppos);
extern struct list_head *seq_list_start_rcu(struct list_head *head, loff_t pos);
extern struct list_head *seq_list_start_head_rcu(struct list_head *head, loff_t pos);
extern struct list_head *seq_list_next_rcu(void *v, struct list_head *head, loff_t *ppos);
/*
* Helpers for iteration over hlist_head-s in seq_files
*/
extern struct hlist_node *seq_hlist_start(struct hlist_head *head,
loff_t pos);
extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head,
loff_t pos);
extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
loff_t *ppos);
extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head,
loff_t pos);
extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
loff_t pos);
extern struct hlist_node *seq_hlist_next_rcu(void *v,
struct hlist_head *head,
loff_t *ppos);
/* Helpers for iterating over per-cpu hlist_head-s in seq_files */
extern struct hlist_node *seq_hlist_start_percpu(struct hlist_head __percpu *head, int *cpu, loff_t pos);
extern struct hlist_node *seq_hlist_next_percpu(void *v, struct hlist_head __percpu *head, int *cpu, loff_t *pos);
void seq_file_init(void);
#endif
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