1 /*
2 * Copyright (c) 2006-2025 RT-Thread Development Team
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 *
6 * Change Logs:
7 * Date Author Notes
8 */
9
10 #ifndef __DFS_SEQ_FILE_H__
11 #define __DFS_SEQ_FILE_H__
12
13 #include <dfs.h>
14 #include <dfs_fs.h>
15
16 struct dfs_seq_ops;
17
18 /**
19 * Sequence file control structure
20 */
21 struct dfs_seq_file
22 {
23 char *buf; /* Data buffer pointer */
24 size_t size; /* Total buffer size in bytes */
25 size_t from; /* Start offset of valid data in buffer */
26 size_t count; /* Length of valid data in buffer */
27 size_t pad_until; /* Padding target position for alignment */
28
29 off_t index; /* Current item index in sequence */
30 off_t read_pos; /* Current read position in file */
31
32 struct rt_mutex lock; /* Mutex for thread safety */
33
34 const struct dfs_seq_ops *ops; /* Operation function table */
35 const struct dfs_file *file; /* Associated file object */
36 void *data; /* Private data pointer */
37 };
38
39 /**
40 * Sequence file operations structure
41 */
42 struct dfs_seq_ops
43 {
44 void *(*start)(struct dfs_seq_file *seq, off_t *index); /* Start sequence traversal */
45 void (*stop)(struct dfs_seq_file *seq, void *data); /* Stop sequence traversal */
46 void *(*next)(struct dfs_seq_file *seq, void *data, off_t *index); /* Get next item in sequence */
47 int (*show)(struct dfs_seq_file *seq, void *data); /* Show current item */
48 };
49
50 /**
51 * check if the buffer is full
52 */
dfs_seq_is_full(struct dfs_seq_file * seq)53 static inline rt_bool_t dfs_seq_is_full(struct dfs_seq_file *seq)
54 {
55 return seq->count == seq->size;
56 }
57
58 /**
59 * set padding width size
60 */
dfs_seq_setwidth(struct dfs_seq_file * seq,size_t size)61 static inline void dfs_seq_setwidth(struct dfs_seq_file *seq, size_t size)
62 {
63 seq->pad_until = seq->count + size;
64 }
65
66 int dfs_seq_open(struct dfs_file *file, const struct dfs_seq_ops *ops);
67 ssize_t dfs_seq_read(struct dfs_file *file, void *buf, size_t size, off_t *pos);
68 off_t dfs_seq_lseek(struct dfs_file *file, off_t offset, int whence);
69 int dfs_seq_release(struct dfs_file *file);
70 int dfs_seq_write(struct dfs_seq_file *seq, const void *data, size_t len);
71
72 void dfs_seq_vprintf(struct dfs_seq_file *seq, const char *fmt, va_list args);
73 void dfs_seq_printf(struct dfs_seq_file *seq, const char *fmt, ...);
74 void dfs_seq_putc(struct dfs_seq_file *seq, char c);
75 void dfs_seq_puts(struct dfs_seq_file *seq, const char *s);
76 void dfs_seq_pad(struct dfs_seq_file *seq, char c);
77
78 #endif