1 /* $OpenBSD: strerror_r.c,v 1.13 2016/10/19 16:26:16 bluhm Exp $ */
2 /* Public Domain <marc@snafu.org> */
3
4 #include <errno.h>
5 #include <limits.h>
6 #include <signal.h>
7 #include <string.h>
8
9 static size_t
__digits10(unsigned int num)10 __digits10(unsigned int num)
11 {
12 size_t i = 0;
13
14 do {
15 num /= 10;
16 i++;
17 } while (num != 0);
18
19 return i;
20 }
21
22 static int
__itoa(int num,int sign,char * buffer,size_t start,size_t end)23 __itoa(int num, int sign, char *buffer, size_t start, size_t end)
24 {
25 size_t pos;
26 unsigned int a;
27 int neg;
28
29 if (sign && num < 0) {
30 a = -num;
31 neg = 1;
32 }
33 else {
34 a = num;
35 neg = 0;
36 }
37
38 pos = start + __digits10(a);
39 if (neg)
40 pos++;
41
42 if (pos < end)
43 buffer[pos] = '\0';
44 else
45 return ERANGE;
46 pos--;
47 do {
48 buffer[pos] = (a % 10) + '0';
49 pos--;
50 a /= 10;
51 } while (a != 0);
52 if (neg)
53 buffer[pos] = '-';
54 return 0;
55 }
56
57
58 static int
__num2string(int num,int sign,int setid,char * buf,size_t buflen,const char * const list[],size_t max,const char * def)59 __num2string(int num, int sign, int setid, char *buf, size_t buflen,
60 const char * const list[], size_t max, const char *def)
61 {
62 int ret = 0;
63 size_t len;
64
65 if (0 <= num && num < max) {
66 len = strlcpy(buf, list[num], buflen);
67 if (len >= buflen)
68 ret = ERANGE;
69 } else {
70 len = strlcpy(buf, def, buflen);
71 if (len >= buflen)
72 ret = ERANGE;
73 else {
74 ret = __itoa(num, sign, buf, len, buflen);
75 if (ret == 0)
76 ret = EINVAL;
77 }
78 }
79
80 return ret;
81 }
82
83 #define UPREFIX "Unknown error: "
84
85 int
strerror_r(int errnum,char * strerrbuf,size_t buflen)86 strerror_r(int errnum, char *strerrbuf, size_t buflen)
87 {
88 int ret_errno;
89
90 ret_errno = __num2string(errnum, 1, 1, strerrbuf, buflen,
91 sys_errlist, sys_nerr, UPREFIX);
92
93 if (ret_errno)
94 errno = ret_errno;
95 return (ret_errno);
96 }
97 DEF_WEAK(strerror_r);
98
99 #define USIGPREFIX "Unknown signal: "
100
101 char *
__strsignal(int num,char * buf)102 __strsignal(int num, char *buf)
103 {
104 __num2string(num, 0, 2, buf, NL_TEXTMAX, sys_siglist, NSIG,
105 USIGPREFIX);
106 return buf;
107 }
108