simple_shell/string_view.c at main · carsonak/simple_shell · GitHub

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
#include <limits.h>

#include "strings.h"

/**
 * string_readc - returns current character and advances the string cursor.
 * @s: the string.
 *
 * An error is returned if: the cursor position < 0 or cursor position > size
 * or size <= 0.
 * If the cursor is at the end, CHAR_MIN will be returned.
 *
 * Return: the current character, -1 on error.
 */
char string_readc(view_string * const s)
{
	if (!s || s->i < 0 || s->size <= 0 || s->i > s->size)
		return (-1);

	if (s->i == s->size)
		return (CHAR_MIN);

	return (s->s[s->i++]);
}

/**
 * string_readp - returns previous character and retreats the string cursor.
 * @s: the string.
 *
 * An error is returned if: the cursor position < 0 or cursor position >= size
 * or size < 0.
 * If there are no more characters before the cursor,
 * CHAR_MIN will be returned.
 *
 * Return: the previous character, -1 on error.
 */
char string_readp(view_string * const s)
{
	if (!s || s->i < 0 || s->size <= 0 || s->i > s->size)
		return (-1);

	if (s->i == 0)
		return (CHAR_MIN);

	return (s->s[--s->i]);
}

/**
 * string_peekc - returns character at the string cursor.
 * @s: the string.
 *
 * An error is returned if: the cursor position < 0 or cursor position > size
 * or size <= 0.
 * If the cursor is at the end, CHAR_MIN will be returned.
 *
 * Return: the current character, -1 on error.
 */
char string_peekc(view_string const *const s)
{
	if (!s || s->i < 0 || s->size <= 0 || s->i > s->size)
		return (-1);

	if (s->i == s->size)
		return (CHAR_MIN);

	return (s->s[s->i]);
}

/**
 * string_peekp - returns character before the string cursor.
 * @s: the string.
 *
 * An error is returned if: the cursor position < 0 or cursor position >= size
 * or size < 0.
 * If there are no more characters before the cursor,
 * CHAR_MIN will be returned.
 *
 * Return: the previous character, -1 on error.
 */
char string_peekp(view_string const *const s)
{
	if (!s || s->i < 0 || s->size <= 0 || s->i > s->size)
		return (-1);

	if (s->i == 0)
		return (CHAR_MIN);

	return (s->s[s->i - 1]);
}

/**
 * string_peekn - returns character after the string cursor.
 * @s: the string.
 *
 * An error is returned if: the cursor position < 0 or cursor position >= size
 * or size < 0.
 * If the cursor is at the end, CHAR_MIN will be returned.
 *
 * Return: the next character, -1 on error.
 */
char string_peekn(view_string const *const s)
{
	if (!s || s->i < 0 || s->size <= 0 || s->i > s->size)
		return (-1);

	if (s->i == s->size)
		return (CHAR_MIN);

	return (s->s[s->i + 1]);
}