sys/src/9/ip/chandial.c

   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        "../ip/ip.h"
   8
   9 typedef struct DS DS;
  10 static Chan*    call(char*, char*, DS*);
  11 static void     _dial_string_parse(char*, DS*);
  12
  13 enum
  14 {
  15         Maxstring=      128,
  16 };
  17
  18 struct DS
  19 {
  20         char    buf[Maxstring];                 /* dist string */
  21         char    *netdir;
  22         char    *proto;
  23         char    *rem;
  24         char    *local;                         /* other args */
  25         char    *dir;
  26         Chan    **ctlp;
  27 };
  28
  29 /*
  30  *  the dialstring is of the form '[/net/]proto!dest'
  31  */
  32 Chan*
  33 chandial(char *dest, char *local, char *dir, Chan **ctlp)
  34 {
  35         DS ds;
  36         char clone[Maxpath];
  37
  38         ds.local = local;
  39         ds.dir = dir;
  40         ds.ctlp = ctlp;
  41
  42         _dial_string_parse(dest, &ds);
  43         if(ds.netdir == nil)
  44                 ds.netdir = "/net";
  45
  46         /* no connection server, don't translate */
  47         snprint(clone, sizeof(clone), "%s/%s/clone", ds.netdir, ds.proto);
  48         return call(clone, ds.rem, &ds);
  49 }
  50
  51 static Chan*
  52 call(char *clone, char *dest, DS *ds)
  53 {
  54         int n;
  55         Chan *dchan, *cchan;
  56         char name[Maxpath], data[Maxpath], *p;
  57
  58         cchan = namec(clone, Aopen, ORDWR, 0);
  59
  60         /* get directory name */
  61         if(waserror()){
  62                 cclose(cchan);
  63                 nexterror();
  64         }
  65         n = devtab[cchan->type]->read(cchan, name, sizeof(name)-1, 0);
  66         name[n] = 0;
  67         for(p = name; *p == ' '; p++)
  68                 ;
  69         sprint(name, "%lud", strtoul(p, 0, 0));
  70         p = strrchr(clone, '/');
  71         *p = 0;
  72         if(ds->dir)
  73                 snprint(ds->dir, Maxpath, "%s/%s", clone, name);
  74         snprint(data, sizeof(data), "%s/%s/data", clone, name);
  75
  76         /* connect */
  77         if(ds->local)
  78                 snprint(name, sizeof(name), "connect %s %s", dest, ds->local);
  79         else
  80                 snprint(name, sizeof(name), "connect %s", dest);
  81         devtab[cchan->type]->write(cchan, name, strlen(name), 0);
  82
  83         /* open data connection */
  84         dchan = namec(data, Aopen, ORDWR, 0);
  85         if(ds->ctlp)
  86                 *ds->ctlp = cchan;
  87         else
  88                 cclose(cchan);
  89         poperror();
  90         return dchan;
  91
  92 }
  93
  94 /*
  95  *  parse a dial string
  96  */
  97 static void
  98 _dial_string_parse(char *str, DS *ds)
  99 {
 100         char *p, *p2;
 101
 102         strncpy(ds->buf, str, Maxstring);
 103         ds->buf[Maxstring-1] = 0;
 104
 105         p = strchr(ds->buf, '!');
 106         if(p == 0) {
 107                 ds->netdir = 0;
 108                 ds->proto = "net";
 109                 ds->rem = ds->buf;
 110         } else {
 111                 if(*ds->buf != '/' && *ds->buf != '#'){
 112                         ds->netdir = nil;
 113                         ds->proto = ds->buf;
 114                 } else {
 115                         for(p2 = p; *p2 != '/' && p2 != ds->buf; p2--)
 116                                 ;
 117                         if(p2 == ds->buf)
 118                                 error(Ebadarg);
 119                         *p2++ = 0;
 120                         ds->netdir = ds->buf;
 121                         ds->proto = p2;
 122                 }
 123                 *p = 0;
 124                 ds->rem = p + 1;
 125         }
 126 }