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#include <u.h>
#include <libc.h>
typedef struct DS DS;
static int call(char*, char*, DS*);
static int csdial(DS*);
static void _dial_string_parse(char*, DS*);
enum
{
Maxstring = 128,
Maxpath = 256,
};
struct DS {
/* dist string */
char buf[Maxstring];
char *netdir;
char *proto;
char *rem;
/* other args */
char *local;
char *dir;
int *cfdp;
};
/*
* the dialstring is of the form '[/net/]proto!dest'
*/
int
dial(char *dest, char *local, char *dir, int *cfdp)
{
DS ds;
int rv;
char err[ERRMAX], alterr[ERRMAX];
ds.local = local;
ds.dir = dir;
ds.cfdp = cfdp;
_dial_string_parse(dest, &ds);
if(ds.netdir)
return csdial(&ds);
ds.netdir = "/net";
rv = csdial(&ds);
if(rv >= 0)
return rv;
err[0] = '\0';
errstr(err, sizeof err);
if(strstr(err, "refused") != 0){
werrstr("%s", err);
return rv;
}
ds.netdir = "/net.alt";
rv = csdial(&ds);
if(rv >= 0)
return rv;
alterr[0] = 0;
errstr(alterr, sizeof alterr);
if(strstr(alterr, "translate") || strstr(alterr, "does not exist"))
werrstr("%s", err);
else
werrstr("%s", alterr);
return rv;
}
static int
csdial(DS *ds)
{
int n, fd, rv;
char *p, buf[Maxstring], clone[Maxpath], err[ERRMAX], besterr[ERRMAX];
/*
* open connection server
*/
snprint(buf, sizeof(buf), "%s/cs", ds->netdir);
fd = open(buf, ORDWR);
if(fd < 0){
/* no connection server, don't translate */
snprint(clone, sizeof(clone), "%s/%s/clone", ds->netdir, ds->proto);
return call(clone, ds->rem, ds);
}
/*
* ask connection server to translate
*/
snprint(buf, sizeof(buf), "%s!%s", ds->proto, ds->rem);
if(write(fd, buf, strlen(buf)) < 0){
close(fd);
return -1;
}
/*
* loop through each address from the connection server till
* we get one that works.
*/
*besterr = 0;
rv = -1;
seek(fd, 0, 0);
strcpy(err, "cs gave empty translation list");
while((n = read(fd, buf, sizeof(buf) - 1)) > 0){
buf[n] = 0;
p = strchr(buf, ' ');
if(p == 0)
continue;
*p++ = 0;
rv = call(buf, p, ds);
if(rv >= 0)
break;
err[0] = '\0';
errstr(err, sizeof err);
if(strstr(err, "does not exist") == 0)
strcpy(besterr, err);
}
close(fd);
if(rv < 0 && *besterr)
werrstr("%s", besterr);
else
werrstr("%s", err);
return rv;
}
static int
call(char *clone, char *dest, DS *ds)
{
int fd, cfd, n;
char name[Maxpath], data[Maxpath], *p;
cfd = open(clone, ORDWR);
if(cfd < 0)
return -1;
/* get directory name */
n = read(cfd, name, sizeof(name)-1);
if(n < 0){
close(cfd);
return -1;
}
name[n] = 0;
for(p = name; *p == ' '; p++)
;
snprint(name, sizeof(name), "%ld", strtoul(p, 0, 0));
p = strrchr(clone, '/');
*p = 0;
if(ds->dir)
snprint(ds->dir, NETPATHLEN, "%s/%s", clone, name);
snprint(data, sizeof(data), "%s/%s/data", clone, name);
/* connect */
if(ds->local)
snprint(name, sizeof(name), "connect %s %s", dest, ds->local);
else
snprint(name, sizeof(name), "connect %s", dest);
if(write(cfd, name, strlen(name)) < 0){
close(cfd);
return -1;
}
/* open data connection */
fd = open(data, ORDWR);
if(fd < 0){
print("open %s: %r\n", data);
close(cfd);
return -1;
}
if(ds->cfdp)
*ds->cfdp = cfd;
else
close(cfd);
return fd;
}
/*
* parse a dial string
*/
static void
_dial_string_parse(char *str, DS *ds)
{
char *p, *p2;
strncpy(ds->buf, str, Maxstring);
ds->buf[Maxstring-1] = 0;
p = strchr(ds->buf, '!');
if(p == 0) {
ds->netdir = 0;
ds->proto = "net";
ds->rem = ds->buf;
} else {
if(*ds->buf != '/' && *ds->buf != '#'){
ds->netdir = 0;
ds->proto = ds->buf;
} else {
for(p2 = p; *p2 != '/'; p2--)
;
*p2++ = 0;
ds->netdir = ds->buf;
ds->proto = p2;
}
*p = 0;
ds->rem = p + 1;
}
}
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