1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_STRING_HELPERS_H_
3#define _LINUX_STRING_HELPERS_H_
4
5#include <linux/bits.h>
6#include <linux/ctype.h>
7#include <linux/string_choices.h>
8#include <linux/string.h>
9#include <linux/types.h>
10
11struct device;
12struct file;
13struct task_struct;
14
15static inline bool string_is_terminated(const char *s, int len)
16{
17	return memchr(s, '\0', len) ? true : false;
18}
19
20/* Descriptions of the types of units to print in */
21enum string_size_units {
22	STRING_UNITS_10,	/* use powers of 10^3 (standard SI) */
23	STRING_UNITS_2,		/* use binary powers of 2^10 */
24	STRING_UNITS_MASK	= BIT(0),
25
26	/* Modifiers */
27	STRING_UNITS_NO_SPACE	= BIT(30),
28	STRING_UNITS_NO_BYTES	= BIT(31),
29};
30
31int string_get_size(u64 size, u64 blk_size, const enum string_size_units units,
32		    char *buf, int len);
33
34int parse_int_array_user(const char __user *from, size_t count, int **array);
35
36#define UNESCAPE_SPACE		BIT(0)
37#define UNESCAPE_OCTAL		BIT(1)
38#define UNESCAPE_HEX		BIT(2)
39#define UNESCAPE_SPECIAL	BIT(3)
40#define UNESCAPE_ANY		\
41	(UNESCAPE_SPACE | UNESCAPE_OCTAL | UNESCAPE_HEX | UNESCAPE_SPECIAL)
42
43#define UNESCAPE_ALL_MASK	GENMASK(3, 0)
44
45int string_unescape(char *src, char *dst, size_t size, unsigned int flags);
46
47static inline int string_unescape_inplace(char *buf, unsigned int flags)
48{
49	return string_unescape(buf, buf, 0, flags);
50}
51
52static inline int string_unescape_any(char *src, char *dst, size_t size)
53{
54	return string_unescape(src, dst, size, UNESCAPE_ANY);
55}
56
57static inline int string_unescape_any_inplace(char *buf)
58{
59	return string_unescape_any(buf, buf, 0);
60}
61
62#define ESCAPE_SPACE		BIT(0)
63#define ESCAPE_SPECIAL		BIT(1)
64#define ESCAPE_NULL		BIT(2)
65#define ESCAPE_OCTAL		BIT(3)
66#define ESCAPE_ANY		\
67	(ESCAPE_SPACE | ESCAPE_OCTAL | ESCAPE_SPECIAL | ESCAPE_NULL)
68#define ESCAPE_NP		BIT(4)
69#define ESCAPE_ANY_NP		(ESCAPE_ANY | ESCAPE_NP)
70#define ESCAPE_HEX		BIT(5)
71#define ESCAPE_NA		BIT(6)
72#define ESCAPE_NAP		BIT(7)
73#define ESCAPE_APPEND		BIT(8)
74
75#define ESCAPE_ALL_MASK		GENMASK(8, 0)
76
77int string_escape_mem(const char *src, size_t isz, char *dst, size_t osz,
78		unsigned int flags, const char *only);
79
80static inline int string_escape_mem_any_np(const char *src, size_t isz,
81		char *dst, size_t osz, const char *only)
82{
83	return string_escape_mem(src, isz, dst, osz, ESCAPE_ANY_NP, only);
84}
85
86static inline int string_escape_str(const char *src, char *dst, size_t sz,
87		unsigned int flags, const char *only)
88{
89	return string_escape_mem(src, strlen(src), dst, sz, flags, only);
90}
91
92static inline int string_escape_str_any_np(const char *src, char *dst,
93		size_t sz, const char *only)
94{
95	return string_escape_str(src, dst, sz, ESCAPE_ANY_NP, only);
96}
97
98static inline void string_upper(char *dst, const char *src)
99{
100	do {
101		*dst++ = toupper(*src);
102	} while (*src++);
103}
104
105static inline void string_lower(char *dst, const char *src)
106{
107	do {
108		*dst++ = tolower(*src);
109	} while (*src++);
110}
111
112char *kstrdup_quotable(const char *src, gfp_t gfp);
113char *kstrdup_quotable_cmdline(struct task_struct *task, gfp_t gfp);
114char *kstrdup_quotable_file(struct file *file, gfp_t gfp);
115
116char *kstrdup_and_replace(const char *src, char old, char new, gfp_t gfp);
117
118char **kasprintf_strarray(gfp_t gfp, const char *prefix, size_t n);
119void kfree_strarray(char **array, size_t n);
120
121char **devm_kasprintf_strarray(struct device *dev, const char *prefix, size_t n);
122
123#endif
124