Rev 4874 | Details | Compare with Previous | Last modification | View Log | RSS feed
Rev | Author | Line No. | Line |
---|---|---|---|
4349 | Serge | 1 | /* |
2 | FUNCTION |
||
3 | < |
||
4 | |||
5 | INDEX |
||
6 | stpncpy |
||
7 | |||
8 | ANSI_SYNOPSIS |
||
9 | #include |
||
4921 | Serge | 10 | char *stpncpy(char *restrict <[dst]>, const char *restrict <[src]>, |
11 | size_t <[length]>); |
||
4349 | Serge | 12 | |
13 | TRAD_SYNOPSIS |
||
14 | #include |
||
15 | char *stpncpy(<[dst]>, <[src]>, <[length]>) |
||
16 | char *<[dst]>; |
||
17 | char *<[src]>; |
||
18 | size_t <[length]>; |
||
19 | |||
20 | DESCRIPTION |
||
21 | < |
||
22 | the string pointed to by <[src]> (including the terminating |
||
23 | null character) to the array pointed to by <[dst]>. If the |
||
24 | string pointed to by <[src]> is shorter than <[length]> |
||
25 | characters, null characters are appended to the destination |
||
26 | array until a total of <[length]> characters have been |
||
27 | written. |
||
28 | |||
29 | RETURNS |
||
30 | This function returns a pointer to the end of the destination string, |
||
31 | thus pointing to the trailing '\0', or, if the destination string is |
||
32 | not null-terminated, pointing to dst + n. |
||
33 | |||
34 | PORTABILITY |
||
35 | < |
||
36 | |||
37 | < |
||
38 | |||
39 | QUICKREF |
||
40 | stpncpy gnu |
||
41 | */ |
||
42 | |||
43 | #include |
||
44 | #include |
||
45 | |||
46 | /*SUPPRESS 560*/ |
||
47 | /*SUPPRESS 530*/ |
||
48 | |||
49 | /* Nonzero if either X or Y is not aligned on a "long" boundary. */ |
||
50 | #define UNALIGNED(X, Y) \ |
||
51 | (((long)X & (sizeof (long) - 1)) | ((long)Y & (sizeof (long) - 1))) |
||
52 | |||
53 | #if LONG_MAX == 2147483647L |
||
54 | #define DETECTNULL(X) (((X) - 0x01010101) & ~(X) & 0x80808080) |
||
55 | #else |
||
56 | #if LONG_MAX == 9223372036854775807L |
||
57 | /* Nonzero if X (a long int) contains a NULL byte. */ |
||
58 | #define DETECTNULL(X) (((X) - 0x0101010101010101) & ~(X) & 0x8080808080808080) |
||
59 | #else |
||
60 | #error long int is not a 32bit or 64bit type. |
||
61 | #endif |
||
62 | #endif |
||
63 | |||
64 | #ifndef DETECTNULL |
||
65 | #error long int is not a 32bit or 64bit byte |
||
66 | #endif |
||
67 | |||
68 | #define TOO_SMALL(LEN) ((LEN) < sizeof (long)) |
||
69 | |||
70 | char * |
||
71 | _DEFUN (stpncpy, (dst, src), |
||
4921 | Serge | 72 | char *__restrict dst _AND |
73 | _CONST char *__restrict src _AND |
||
4349 | Serge | 74 | size_t count) |
75 | { |
||
76 | char *ret = NULL; |
||
77 | |||
78 | #if !defined(PREFER_SIZE_OVER_SPEED) && !defined(__OPTIMIZE_SIZE__) |
||
79 | long *aligned_dst; |
||
80 | _CONST long *aligned_src; |
||
81 | |||
82 | /* If SRC and DEST is aligned and count large enough, then copy words. */ |
||
83 | if (!UNALIGNED (src, dst) && !TOO_SMALL (count)) |
||
84 | { |
||
85 | aligned_dst = (long*)dst; |
||
86 | aligned_src = (long*)src; |
||
87 | |||
88 | /* SRC and DEST are both "long int" aligned, try to do "long int" |
||
89 | sized copies. */ |
||
90 | while (count >= sizeof (long int) && !DETECTNULL(*aligned_src)) |
||
91 | { |
||
92 | count -= sizeof (long int); |
||
93 | *aligned_dst++ = *aligned_src++; |
||
94 | } |
||
95 | |||
96 | dst = (char*)aligned_dst; |
||
97 | src = (char*)aligned_src; |
||
98 | } |
||
99 | #endif /* not PREFER_SIZE_OVER_SPEED */ |
||
100 | |||
101 | while (count > 0) |
||
102 | { |
||
103 | --count; |
||
104 | if ((*dst++ = *src++) == '\0') |
||
105 | { |
||
106 | ret = dst - 1; |
||
107 | break; |
||
108 | } |
||
109 | } |
||
110 | |||
111 | while (count-- > 0) |
||
112 | *dst++ = '\0'; |
||
113 | |||
114 | return ret ? ret : dst; |
||
115 | }> |