1 /*
2  * We assume there's only one error buffer for the whole system.
3  * If you use ffork, you need to provide a _syserrstr.  Since most
4  * people will use libthread (which provides a _syserrstr), this is
5  * okay.
6  */
7 
8 #include <u.h>
9 #include <errno.h>
10 #include <string.h>
11 #include <libc.h>
12 
13 enum
14 {
15 	EPLAN9 = 0x19283745,
16 };
17 
18 char *(*_syserrstr)(void);
19 static char xsyserr[ERRMAX];
20 static char*
21 getsyserr(void)
22 {
23 	char *s;
24 
25 	s = nil;
26 	if(_syserrstr)
27 		s = (*_syserrstr)();
28 	if(s == nil)
29 		s = xsyserr;
30 	return s;
31 }
32 
33 int
34 errstr(char *err, uint n)
35 {
36 	char tmp[ERRMAX];
37 	char *syserr;
38 
39 	syserr = getsyserr();
40 	if(errno != EPLAN9)
41 		strcpy(syserr, strerror(errno));
42 
43 	strecpy(tmp, tmp+ERRMAX, syserr);
44 	strecpy(syserr, syserr+ERRMAX, err);
45 	strecpy(err, err+n, tmp);
46 	errno = EPLAN9;
47 	return 0;
48 }
49 
50 void
51 rerrstr(char *err, uint n)
52 {
53 	char *syserr;
54 
55 	syserr = getsyserr();
56 	if(errno != EPLAN9)
57 		strcpy(syserr, strerror(errno));
58 	strecpy(err, err+n, syserr);
59 }
60 
61 /* replaces __errfmt in libfmt */
62 
63 int
64 __errfmt(Fmt *f)
65 {
66 	if(errno == EPLAN9)
67 		return fmtstrcpy(f, getsyserr());
68 	return fmtstrcpy(f, strerror(errno));
69 }
70 
71 void
72 werrstr(char *fmt, ...)
73 {
74 	va_list arg;
75 	char buf[ERRMAX];
76 
77 	va_start(arg, fmt);
78 	vseprint(buf, buf+ERRMAX, fmt, arg);
79 	va_end(arg);
80 	errstr(buf, ERRMAX);
81 }
82 
83 char*
84 gerrstr(void)
85 {
86 	char *s;
87 
88 	s = getsyserr();
89 	if(errno != EPLAN9)
90 		strcpy(s, strerror(errno));
91 	return s;
92 }
93 
94