~kris/9p

9hist

ref: f4322fa8bc0a34b2fb3f63c84ab1ad4fb1647c4e 9hist/port/devdup.c -rw-r--r-- 1.7 KiB
f4322fa8 — David du Colombier Plan 9 from Bell Labs 1993-02-25 33 years ago
                                                                                
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
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
#include	"u.h"
#include	"../port/lib.h"
#include	"mem.h"
#include	"dat.h"
#include	"fns.h"
#include	"../port/error.h"

#include	"devtab.h"


int
dupgen(Chan *c, Dirtab *tab, int ntab, int s, Dir *dp)
{
	char buf[8];
	Fgrp *fgrp = u->p->fgrp;
	Chan *f;
	static int perm[] = { 0400, 0200, 0600, 0 };

	USED(tab);
	USED(ntab);
	if(s >= NFD)
		return -1;
	if((f=fgrp->fd[s]) == 0)
		return 0;
	sprint(buf, "%ld", s);
	devdir(c, (Qid){s, 0}, buf, 0, eve, perm[f->mode&3], dp);
	return 1;
}

void
dupinit(void)
{
}

void
dupreset(void)
{
}

Chan *
dupattach(char *spec)
{
	return devattach('d', spec);
}

Chan *
dupclone(Chan *c, Chan *nc)
{
	return devclone(c, nc);
}

int
dupwalk(Chan *c, char *name)
{
	return devwalk(c, name, (Dirtab *)0, 0, dupgen);
}

void
dupstat(Chan *c, char *db)
{
	devstat(c, db, (Dirtab *)0, 0L, dupgen);
}

Chan *
dupopen(Chan *c, int omode)
{
	Chan *f;

	if(c->qid.path == CHDIR){
		if(omode != 0)
			error(Eisdir);
		c->mode = 0;
		c->flag |= COPEN;
		c->offset = 0;
		return c;
	}
	fdtochan(c->qid.path, openmode(omode), 0, 0);	/* error check only */
	f = u->p->fgrp->fd[c->qid.path];
	close(c);
	incref(f);
	if(omode & OCEXEC)
		f->flag |= CCEXEC;
	return f;
}

void
dupcreate(Chan *c, char *name, int omode, ulong perm)
{
	USED(c, name, omode, perm);
	error(Eperm);
}

void
dupremove(Chan *c)
{
	USED(c);
	error(Eperm);
}

void
dupwstat(Chan *c, char *dp)
{
	USED(c);
	USED(dp);
	error(Egreg);
}

void
dupclose(Chan *c)
{
	USED(c);
}

long
dupread(Chan *c, void *va, long n, ulong offset)
{
	char *a = va;

	USED(offset);
	if(c->qid.path != CHDIR)
		panic("dupread");
	return devdirread(c, a, n, (Dirtab *)0, 0L, dupgen);
}

long
dupwrite(Chan *c, void *va, long n, ulong offset)
{
	USED(c, va, n, offset);
	panic("dupwrite");
	return 0;		/* not reached */
}