ref: dde3628d54073e0569bf565e6ec861e42cfa35f6
dir: /sys/src/cmd/cec/cec.c/
/*
* cec — coraid ethernet console
* Copyright © Coraid, Inc. 2006-2008.
* All Rights Reserved.
*/
#include <u.h>
#include <libc.h>
#include <ip.h> /* really! */
#include <ctype.h>
#include "cec.h"
enum {
Tinita = 0,
Tinitb,
Tinitc,
Tdata,
Tack,
Tdiscover,
Toffer,
Treset,
Hdrsz = 18,
Eaddrlen = 6,
};
typedef struct{
uchar ea[Eaddrlen];
int major;
char name[28];
} Shelf;
int conn(int);
void gettingkilled(int);
int pickone(void);
void probe(void);
void sethdr(Pkt *, int);
int shelfidx(void);
Shelf *con;
Shelf tab[1000];
char *host;
char *srv;
char *svc;
char pflag;
int ntab;
int shelf = -1;
uchar bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
uchar contag;
uchar esc = ' ';
uchar ea[Eaddrlen];
uchar unsetea[Eaddrlen];
extern int fd; /* set in netopen */
void
post(char *srv, int fd)
{
char buf[32];
int f;
if((f = create(srv, OWRITE, 0666)) == -1)
sysfatal("create %s: %r", srv);
snprint(buf, sizeof buf, "%d", fd);
if(write(f, buf, strlen(buf)) != strlen(buf))
sysfatal("write %s: %r", srv);
close(f);
}
void
dosrv(char *s)
{
int p[2];
if(pipe(p) < 0)
sysfatal("pipe: %r");
if (srv[0] != '/')
svc = smprint("/srv/%s", s);
else
svc = smprint("%s", s);
post(svc, p[0]);
close(p[0]);
dup(p[1], 0);
dup(p[1], 1);
switch(rfork(RFFDG|RFPROC|RFNAMEG|RFNOTEG)){
case -1:
sysfatal("fork: %r");
case 0:
break;
default:
exits("");
}
close(2);
}
void
usage(void)
{
fprint(2, "usage: cec [-dp] [-c esc] [-e ea] [-h host] [-s shelf] "
"[-S srv] interface\n");
exits0("usage");
}
void
catch(void*, char *note)
{
if(strcmp(note, "alarm") == 0)
noted(NCONT);
noted(NDFLT);
}
int
nilea(uchar *ea)
{
return memcmp(ea, unsetea, Eaddrlen) == 0;
}
void
main(int argc, char **argv)
{
int r, n;
ARGBEGIN{
case 'S':
srv = EARGF(usage());
break;
case 'c':
esc = tolower(*(EARGF(usage()))) - 'a' + 1;
if(esc == 0 || esc >= ' ')
usage();
break;
case 'd':
debug++;
break;
case 'e':
if(parseether(ea, EARGF(usage())) == -1)
usage();
pflag = 1;
break;
case 'h':
host = EARGF(usage());
break;
case 'p':
pflag = 1;
break;
case 's':
shelf = atoi(EARGF(usage()));
break;
default:
usage();
}ARGEND
if(argc == 0)
*argv = "/net/ether0";
else if(argc != 1)
usage();
fmtinstall('E', eipfmt);
if(srv != nil)
dosrv(srv);
r = netopen(*argv);
if(r == -1){
fprint(2, "cec: can't netopen %s\n", *argv);
exits0("open");
}
notify(catch);
probe();
for(;;){
n = 0;
if(shelf == -1 && host == 0 && nilea(ea))
n = pickone();
rawon();
conn(n);
rawoff();
if(pflag == 0){
if(shelf != -1)
exits0("shelf not found");
if(host)
exits0("host not found");
if(!nilea(ea))
exits0("ea not found");
} else if(shelf != -1 || host || !nilea(ea))
exits0("");
}
}
void
timewait(int ms)
{
alarm(ms);
}
int
didtimeout(void)
{
char err[ERRMAX];
int rv;
*err = 0;
errstr(err, sizeof err);
rv = strcmp(err, "interrupted") == 0;
errstr(err, sizeof err);
return rv;
}
ushort
htons(ushort h)
{
ushort n;
uchar *p;
p = (uchar*)&n;
p[0] = h >> 8;
p[1] = h;
return n;
}
ushort
ntohs(int h)
{
ushort n;
uchar *p;
n = h;
p = (uchar*)&n;
return p[0] << 8 | p[1];
}
int
tcmp(void *a, void *b)
{
Shelf *s, *t;
int d;
s = a;
t = b;
d = s->major - t->major;
if(d == 0)
d = strcmp(s->name, t->name);
if(d == 0)
d = memcmp(s->ea, t->ea, Eaddrlen);
return d;
}
void
probe(void)
{
char *sh, *other;
int n;
Pkt q;
Shelf *p;
do {
ntab = 0;
memset(q.dst, 0xff, Eaddrlen);
memset(q.src, 0, Eaddrlen);
q.etype = htons(Etype);
q.type = Tdiscover;
q.len = 0;
q.conn = 0;
q.seq = 0;
netsend(&q, 60);
timewait(Iowait);
while((n = netget(&q, sizeof q)) >= 0){
if((n <= 0 && didtimeout()) || ntab == nelem(tab))
break;
if(n < 60 || q.len == 0 || q.type != Toffer)
continue;
q.data[q.len] = 0;
sh = strtok((char *)q.data, " \t");
if(sh == nil)
continue;
if(!nilea(ea) && memcmp(ea, q.src, Eaddrlen) != 0)
continue;
if(shelf != -1 && atoi(sh) != shelf)
continue;
other = strtok(nil, "\x1");
if(other == 0)
other = "";
if(host && strcmp(host, other) != 0)
continue;
p = tab + ntab++;
memcpy(p->ea, q.src, Eaddrlen);
p->major = atoi(sh);
p->name[0] = 0;
if(p->name)
snprint(p->name, sizeof p->name, "%s", other);
}
alarm(0);
} while (ntab == 0 && pflag);
if(ntab == 0){
fprint(2, "none found.\n");
exits0("none found");
}
qsort(tab, ntab, sizeof tab[0], tcmp);
}
void
showtable(void)
{
int i;
for(i = 0; i < ntab; i++)
print("%2d %5d %E %s\n", i, tab[i].major, tab[i].ea, tab[i].name);
}
int
pickone(void)
{
char buf[80];
int n, i;
for(;;){
showtable();
print("[#qp]: ");
switch(n = read(0, buf, sizeof buf)){
case 1:
if(buf[0] == '\n')
continue;
/* fall through */
case 2:
if(buf[0] == 'p'){
probe();
break;
}
if(buf[0] == 'q')
/* fall through */
case 0:
case -1:
exits0(0);
break;
}
if(isdigit(buf[0])){
buf[n] = 0;
i = atoi(buf);
if(i >= 0 && i < ntab)
break;
}
}
return i;
}
void
sethdr(Pkt *pp, int type)
{
memmove(pp->dst, con->ea, Eaddrlen);
memset(pp->src, 0, Eaddrlen);
pp->etype = htons(Etype);
pp->type = type;
pp->len = 0;
pp->conn = contag;
}
void
ethclose(void)
{
static Pkt msg;
sethdr(&msg, Treset);
timewait(Iowait);
netsend(&msg, 60);
alarm(0);
con = 0;
}
int
ethopen(void)
{
Pkt tpk, rpk;
int i, n;
contag = (getpid() >> 8) ^ (getpid() & 0xff);
sethdr(&tpk, Tinita);
sethdr(&rpk, 0);
for(i = 0; i < 3 && rpk.type != Tinitb; i++){
netsend(&tpk, 60);
timewait(Iowait);
n = netget(&rpk, 1000);
alarm(0);
if(n < 0)
return -1;
}
if(rpk.type != Tinitb)
return -1;
sethdr(&tpk, Tinitc);
netsend(&tpk, 60);
return 0;
}
char
escape(void)
{
char buf[64];
int r;
for(;;){
fprint(2, ">>> ");
buf[0] = '.';
rawoff();
r = read(0, buf, sizeof buf - 1);
rawon();
if(r == -1)
exits0("kbd: %r");
switch(buf[0]){
case 'i':
case 'q':
case '.':
return buf[0];
}
fprint(2, " (q)uit, (i)nterrupt, (.)continue\n");
}
}
/*
* this is a bit too aggressive. it really needs to replace only \n\r with \n.
*/
static uchar crbuf[256];
void
nocrwrite(int fd, uchar *buf, int n)
{
int i, j, c;
j = 0;
for(i = 0; i < n; i++)
if((c = buf[i]) != '\r')
crbuf[j++] = c;
write(fd, crbuf, j);
}
int
doloop(void)
{
int unacked, retries, set[2];
uchar c, tseq, rseq;
uchar ea[Eaddrlen];
Pkt tpk, spk;
Mux *m;
memmove(ea, con->ea, Eaddrlen);
retries = 0;
unacked = 0;
tseq = 0;
rseq = -1;
set[0] = 0;
set[1] = fd;
top:
if ((m = mux(set)) == 0)
exits0("mux: %r");
for (; ; )
switch (muxread(m, &spk)) {
case -1:
if (unacked == 0)
break;
if (retries-- == 0) {
fprint(2, "Connection timed out\n");
muxfree(m);
return 0;
}
netsend(&tpk, Hdrsz + unacked);
break;
case Fkbd:
c = spk.data[0];
if (c == esc) {
muxfree(m);
switch (escape()) {
case 'q':
tpk.len = 0;
tpk.type = Treset;
netsend(&tpk, 60);
return 0;
case '.':
goto top;
case 'i':
if ((m = mux(set)) == 0)
exits0("mux: %r");
break;
}
}
sethdr(&tpk, Tdata);
memcpy(tpk.data, spk.data, spk.len);
tpk.len = spk.len;
tpk.seq = ++tseq;
unacked = spk.len;
retries = 2;
netsend(&tpk, Hdrsz + spk.len);
break;
case Fcec:
if (memcmp(spk.src, ea, Eaddrlen) != 0 ||
ntohs(spk.etype) != Etype)
continue;
if (spk.type == Toffer &&
memcmp(spk.dst, bcast, Eaddrlen) != 0) {
muxfree(m);
return 1;
}
if (spk.conn != contag)
continue;
switch (spk.type) {
case Tdata:
if (spk.seq == rseq)
break;
nocrwrite(1, spk.data, spk.len);
memmove(spk.dst, spk.src, Eaddrlen);
memset(spk.src, 0, Eaddrlen);
spk.type = Tack;
spk.len = 0;
rseq = spk.seq;
netsend(&spk, 60);
break;
case Tack:
if (spk.seq == tseq)
unacked = 0;
break;
case Treset:
muxfree(m);
return 1;
}
break;
case Ffatal:
muxfree(m);
fprint(2, "kbd read error\n");
exits0("fatal");
}
}
int
conn(int n)
{
int r;
for(;;){
if(con)
ethclose();
con = tab + n;
if(ethopen() < 0){
fprint(2, "connection failed\n");
return 0;
}
r = doloop();
if(r <= 0)
return r;
}
}
void
exits0(char *s)
{
if(con != nil)
ethclose();
rawoff();
if(svc != nil)
remove(svc);
exits(s);
}