1 #include "u.h"
2 #include "../port/lib.h"
3 #include "mem.h"
4 #include "dat.h"
5 #include "fns.h"
6 #include "../port/error.h"
7 #include "io.h"
8
9 enum {
10 Qdir = 0,
11 Qbase,
12
13 Qmax = 16,
14 };
15
16 typedef long Rdwrfn(Chan*, void*, long, vlong);
17
18 static Rdwrfn *readfn[Qmax];
19 static Rdwrfn *writefn[Qmax];
20
21 static Dirtab archdir[Qmax] = {
22 ".", { Qdir, 0, QTDIR }, 0, 0555,
23 };
24
25 Lock archwlock; /* the lock is only for changing archdir */
26 int narchdir = Qbase;
27
28 /*
29 * Add a file to the #P listing. Once added, you can't delete it.
30 * You can't add a file with the same name as one already there,
31 * and you get a pointer to the Dirtab entry so you can do things
32 * like change the Qid version. Changing the Qid path is disallowed.
33 */
34 Dirtab*
addarchfile(char * name,int perm,Rdwrfn * rdfn,Rdwrfn * wrfn)35 addarchfile(char *name, int perm, Rdwrfn *rdfn, Rdwrfn *wrfn)
36 {
37 int i;
38 Dirtab d;
39 Dirtab *dp;
40
41 memset(&d, 0, sizeof d);
42 strcpy(d.name, name);
43 d.perm = perm;
44
45 lock(&archwlock);
46 if(narchdir >= Qmax){
47 unlock(&archwlock);
48 return nil;
49 }
50
51 for(i=0; i<narchdir; i++)
52 if(strcmp(archdir[i].name, name) == 0){
53 unlock(&archwlock);
54 return nil;
55 }
56
57 d.qid.path = narchdir;
58 archdir[narchdir] = d;
59 readfn[narchdir] = rdfn;
60 writefn[narchdir] = wrfn;
61 dp = &archdir[narchdir++];
62 unlock(&archwlock);
63
64 return dp;
65 }
66
67 static Chan*
archattach(char * spec)68 archattach(char* spec)
69 {
70 return devattach('P', spec);
71 }
72
73 Walkqid*
archwalk(Chan * c,Chan * nc,char ** name,int nname)74 archwalk(Chan* c, Chan *nc, char** name, int nname)
75 {
76 return devwalk(c, nc, name, nname, archdir, narchdir, devgen);
77 }
78
79 static int
archstat(Chan * c,uchar * dp,int n)80 archstat(Chan* c, uchar* dp, int n)
81 {
82 return devstat(c, dp, n, archdir, narchdir, devgen);
83 }
84
85 static Chan*
archopen(Chan * c,int omode)86 archopen(Chan* c, int omode)
87 {
88 return devopen(c, omode, archdir, narchdir, devgen);
89 }
90
91 static void
archclose(Chan *)92 archclose(Chan*)
93 {
94 }
95
96 static long
archread(Chan * c,void * a,long n,vlong offset)97 archread(Chan *c, void *a, long n, vlong offset)
98 {
99 Rdwrfn *fn;
100
101 switch((ulong)c->qid.path){
102 case Qdir:
103 return devdirread(c, a, n, archdir, narchdir, devgen);
104
105 default:
106 if(c->qid.path < narchdir && (fn = readfn[c->qid.path]))
107 return fn(c, a, n, offset);
108 error(Eperm);
109 break;
110 }
111
112 return 0;
113 }
114
115 static long
archwrite(Chan * c,void * a,long n,vlong offset)116 archwrite(Chan *c, void *a, long n, vlong offset)
117 {
118 Rdwrfn *fn;
119
120 if(c->qid.path < narchdir && (fn = writefn[c->qid.path]))
121 return fn(c, a, n, offset);
122 error(Eperm);
123
124 return 0;
125 }
126
127 void archinit(void);
128
129 Dev archdevtab = {
130 'P',
131 "arch",
132
133 devreset,
134 archinit,
135 devshutdown,
136 archattach,
137 archwalk,
138 archstat,
139 archopen,
140 devcreate,
141 archclose,
142 archread,
143 devbread,
144 archwrite,
145 devbwrite,
146 devremove,
147 devwstat,
148 };
149
150 static long
cputyperead(Chan *,void * a,long n,vlong offset)151 cputyperead(Chan*, void *a, long n, vlong offset)
152 {
153 char str[128];
154
155 snprint(str, sizeof str, "ARM11 %d\n", m->cpumhz);
156 return readstr(offset, a, n, str);
157 }
158
159 void
archinit(void)160 archinit(void)
161 {
162 addarchfile("cputype", 0444, cputyperead, nil);
163 }
164