summaryrefslogtreecommitdiff
path: root/lib/ccan/str/str.h
blob: ae51cdcc998e85b6a5014239bbd5cadc1bc9cda8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
#ifndef CCAN_STR_H
#define CCAN_STR_H
#include "config.h"
#include <string.h>
#include <stdbool.h>
#include <ctype.h>

/**
 * streq - Are two strings equal?
 * @a: first string
 * @b: first string
 *
 * This macro is arguably more readable than "!strcmp(a, b)".
 *
 * Example:
 *	if (streq(somestring, ""))
 *		printf("String is empty!\n");
 */
#define streq(a,b) (strcmp((a),(b)) == 0)

/**
 * strstarts - Does this string start with this prefix?
 * @str: string to test
 * @prefix: prefix to look for at start of str
 *
 * Example:
 *	if (strstarts(somestring, "foo"))
 *		printf("String %s begins with 'foo'!\n", somestring);
 */
#define strstarts(str,prefix) (strncmp((str),(prefix),strlen(prefix)) == 0)

/**
 * strends - Does this string end with this postfix?
 * @str: string to test
 * @postfix: postfix to look for at end of str
 *
 * Example:
 *	if (strends(somestring, "foo"))
 *		printf("String %s end with 'foo'!\n", somestring);
 */
static inline bool strends(const char *str, const char *postfix)
{
	if (strlen(str) < strlen(postfix))
		return false;

	return streq(str + strlen(str) - strlen(postfix), postfix);
}

/**
 * stringify - Turn expression into a string literal
 * @expr: any C expression
 *
 * Example:
 *	#define PRINT_COND_IF_FALSE(cond) \
 *		((cond) || printf("%s is false!", stringify(cond)))
 */
#define stringify(expr)		stringify_1(expr)
/* Double-indirection required to stringify expansions */
#define stringify_1(expr)	#expr

/**
 * strcount - Count number of (non-overlapping) occurrences of a substring.
 * @haystack: a C string
 * @needle: a substring
 *
 * Example:
 *	int i;
 *      i = strcount("aaa aaa", "a");  // i = 6;
 *      i = strcount("aaa aaa", "ab"); // i = 0;
 *      i = strcount("aaa aaa", "aa"); // i = 2;
 */
size_t strcount(const char *haystack, const char *needle);

/**
 * cisalnum - isalnum() which takes a char (and doesn't accept EOF)
 * @c: a character
 *
 * Surprisingly, the standard ctype.h isalnum() takes an int, which
 * must have the value of EOF (-1) or an unsigned char.  This variant
 * takes a real char, and doesn't accept EOF.
 */
static inline bool cisalnum(char c)
{
	return isalnum((unsigned char)c);
}
static inline bool cisalpha(char c)
{
	return isalpha((unsigned char)c);
}
static inline bool cisascii(char c)
{
	return isascii((unsigned char)c);
}
#if HAVE_ISBLANK
static inline bool cisblank(char c)
{
	return isblank((unsigned char)c);
}
#endif
static inline bool ciscntrl(char c)
{
	return iscntrl((unsigned char)c);
}
static inline bool cisdigit(char c)
{
	return isdigit((unsigned char)c);
}
static inline bool cisgraph(char c)
{
	return isgraph((unsigned char)c);
}
static inline bool cislower(char c)
{
	return islower((unsigned char)c);
}
static inline bool cisprint(char c)
{
	return isprint((unsigned char)c);
}
static inline bool cispunct(char c)
{
	return ispunct((unsigned char)c);
}
static inline bool cisspace(char c)
{
	return isspace((unsigned char)c);
}
static inline bool cisupper(char c)
{
	return isupper((unsigned char)c);
}
static inline bool cisxdigit(char c)
{
	return isxdigit((unsigned char)c);
}

#include <ccan/str/str_debug.h>

/* These checks force things out of line, hence they are under DEBUG. */
#ifdef CCAN_STR_DEBUG
#include <ccan/build_assert/build_assert.h>

/* These are commonly misused: they take -1 or an *unsigned* char value. */
#undef isalnum
#undef isalpha
#undef isascii
#undef isblank
#undef iscntrl
#undef isdigit
#undef isgraph
#undef islower
#undef isprint
#undef ispunct
#undef isspace
#undef isupper
#undef isxdigit

/* You can use a char if char is unsigned. */
#if HAVE_BUILTIN_TYPES_COMPATIBLE_P && HAVE_TYPEOF
#define str_check_arg_(i)						\
	((i) + BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(typeof(i), \
								  char)	\
				    || (char)255 > 0))
#else
#define str_check_arg_(i) (i)
#endif

#define isalnum(i) str_isalnum(str_check_arg_(i))
#define isalpha(i) str_isalpha(str_check_arg_(i))
#define isascii(i) str_isascii(str_check_arg_(i))
#if HAVE_ISBLANK
#define isblank(i) str_isblank(str_check_arg_(i))
#endif
#define iscntrl(i) str_iscntrl(str_check_arg_(i))
#define isdigit(i) str_isdigit(str_check_arg_(i))
#define isgraph(i) str_isgraph(str_check_arg_(i))
#define islower(i) str_islower(str_check_arg_(i))
#define isprint(i) str_isprint(str_check_arg_(i))
#define ispunct(i) str_ispunct(str_check_arg_(i))
#define isspace(i) str_isspace(str_check_arg_(i))
#define isupper(i) str_isupper(str_check_arg_(i))
#define isxdigit(i) str_isxdigit(str_check_arg_(i))

#if HAVE_TYPEOF
/* With GNU magic, we can make const-respecting standard string functions. */
#undef strstr
#undef strchr
#undef strrchr

/* + 0 is needed to decay array into pointer. */
#define strstr(haystack, needle)					\
	((typeof((haystack) + 0))str_strstr((haystack), (needle)))
#define strchr(haystack, c)					\
	((typeof((haystack) + 0))str_strchr((haystack), (c)))
#define strrchr(haystack, c)					\
	((typeof((haystack) + 0))str_strrchr((haystack), (c)))
#endif
#endif /* CCAN_STR_DEBUG */

#endif /* CCAN_STR_H */