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-rw-r--r--apps/plugins/lib/strncpy.c125
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diff --git a/apps/plugins/lib/strncpy.c b/apps/plugins/lib/strncpy.c
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1/*
2FUNCTION
3 <<strncpy>>---counted copy string
4
5INDEX
6 strncpy
7
8ANSI_SYNOPSIS
9 #include <string.h>
10 char *strncpy(char *<[dst]>, const char *<[src]>, size_t <[length]>);
11
12TRAD_SYNOPSIS
13 #include <string.h>
14 char *strncpy(<[dst]>, <[src]>, <[length]>)
15 char *<[dst]>;
16 char *<[src]>;
17 size_t <[length]>;
18
19DESCRIPTION
20 <<strncpy>> copies not more than <[length]> characters from the
21 the string pointed to by <[src]> (including the terminating
22 null character) to the array pointed to by <[dst]>. If the
23 string pointed to by <[src]> is shorter than <[length]>
24 characters, null characters are appended to the destination
25 array until a total of <[length]> characters have been
26 written.
27
28RETURNS
29 This function returns the initial value of <[dst]>.
30
31PORTABILITY
32<<strncpy>> is ANSI C.
33
34<<strncpy>> requires no supporting OS subroutines.
35
36QUICKREF
37 strncpy ansi pure
38*/
39
40#include <string.h>
41#include <limits.h>
42
43/*SUPPRESS 560*/
44/*SUPPRESS 530*/
45
46/* Nonzero if either X or Y is not aligned on a "long" boundary. */
47#define UNALIGNED(X, Y) \
48 (((long)X & (sizeof (long) - 1)) | ((long)Y & (sizeof (long) - 1)))
49
50#if LONG_MAX == 2147483647L
51#define DETECTNULL(X) (((X) - 0x01010101) & ~(X) & 0x80808080)
52#else
53#if LONG_MAX == 9223372036854775807L
54/* Nonzero if X (a long int) contains a NULL byte. */
55#define DETECTNULL(X) (((X) - 0x0101010101010101) & ~(X) & 0x8080808080808080)
56#else
57#error long int is not a 32bit or 64bit type.
58#endif
59#endif
60
61#ifndef DETECTNULL
62#error long int is not a 32bit or 64bit byte
63#endif
64
65#define TOO_SMALL(LEN) ((LEN) < sizeof (long))
66
67char *
68_DEFUN (strncpy, (dst0, src0),
69 char *dst0 _AND
70 _CONST char *src0 _AND
71 size_t count)
72{
73#if defined(PREFER_SIZE_OVER_SPEED) || defined(__OPTIMIZE_SIZE__)
74 char *dscan;
75 _CONST char *sscan;
76
77 dscan = dst0;
78 sscan = src0;
79 while (count > 0)
80 {
81 --count;
82 if ((*dscan++ = *sscan++) == '\0')
83 break;
84 }
85 while (count-- > 0)
86 *dscan++ = '\0';
87
88 return dst0;
89#else
90 char *dst = dst0;
91 _CONST char *src = src0;
92 long *aligned_dst;
93 _CONST long *aligned_src;
94
95 /* If SRC and DEST is aligned and count large enough, then copy words. */
96 if (!UNALIGNED (src, dst) && !TOO_SMALL (count))
97 {
98 aligned_dst = (long*)dst;
99 aligned_src = (long*)src;
100
101 /* SRC and DEST are both "long int" aligned, try to do "long int"
102 sized copies. */
103 while (count >= sizeof (long int) && !DETECTNULL(*aligned_src))
104 {
105 count -= sizeof (long int);
106 *aligned_dst++ = *aligned_src++;
107 }
108
109 dst = (char*)aligned_dst;
110 src = (char*)aligned_src;
111 }
112
113 while (count > 0)
114 {
115 --count;
116 if ((*dst++ = *src++) == '\0')
117 break;
118 }
119
120 while (count-- > 0)
121 *dst++ = '\0';
122
123 return dst0;
124#endif /* not PREFER_SIZE_OVER_SPEED */
125}