sys/src/cmd/aux/conswdir.c

   1 /*
   2  * Process in-band messages about window title changes.
   3  * The messages are of the form:
   4  *
   5  *      \033];xxx\007
   6  *
   7  * where xxx is the new directory.  This format was chosen
   8  * because it changes the label on xterm windows.
   9  */
  10
  11 #include <u.h>
  12 #include <libc.h>
  13
  14 struct {
  15         char *file;
  16         char name[512];
  17 } keep[] = {
  18         { "/dev/label" },
  19         { "/dev/wdir" }
  20 };
  21
  22 char *prog = "/bin/rwd";
  23
  24 void
  25 usage(void)
  26 {
  27         fprint(2, "usage: conswdir [/bin/rwd]\n");
  28         exits("usage");
  29 }
  30
  31 void
  32 save(void)
  33 {
  34         int i, fd;
  35         for(i = 0; i < nelem(keep); i++){
  36                 *keep[i].name = 0;
  37                 if((fd = open(keep[i].file, OREAD)) != -1){
  38                         read(fd, keep[i].name, sizeof(keep[i].name));
  39                         close(fd);
  40                 }
  41         }
  42 }
  43
  44 void
  45 rest(void)
  46 {
  47         int i, fd;
  48         for(i = 0; i < nelem(keep); i++)
  49                 if((fd = open(keep[i].file, OWRITE)) != -1){
  50                         write(fd, keep[i].name, strlen(keep[i].name));
  51                         close(fd);
  52                 }
  53
  54 }
  55
  56 void
  57 setpath(char *s)
  58 {
  59         switch(rfork(RFPROC|RFFDG|RFNOWAIT)){
  60         case 0:
  61                 execl(prog, prog, s, nil);
  62                 _exits(nil);
  63         }
  64 }
  65
  66 enum
  67 {
  68         None,
  69         Esc,
  70         Brack,
  71         Semi,
  72         Bell,
  73 };
  74
  75 int
  76 process(char *buf, int n, int *pn)
  77 {
  78         char *p;
  79         char path[4096];
  80         int start, state;
  81
  82         start = 0;
  83         state = None;
  84         for(p=buf; p<buf+n; p++){
  85                 switch(state){
  86                 case None:
  87                         if(*p == '\033'){
  88                                 start = p-buf;
  89                                 state++;
  90                         }
  91                         break;
  92                 case Esc:
  93                         if(*p == ']')
  94                                 state++;
  95                         else
  96                                 state = None;
  97                         break;
  98                 case Brack:
  99                         if(*p == ';')
 100                                 state++;
 101                         else
 102                                 state = None;
 103                         break;
 104                 case Semi:
 105                         if(*p == '\007')
 106                                 state++;
 107                         else if((uchar)*p < 040)
 108                                 state = None;
 109                         break;
 110                 }
 111                 if(state == Bell){
 112                         memmove(path, buf+start+3, p - (buf+start+3));
 113                         path[p-(buf+start+3)] = 0;
 114                         p++;
 115                         memmove(buf+start, p, n-(p-buf));
 116                         n -= p-(buf+start);
 117                         p = buf+start;
 118                         p--;
 119                         start = 0;
 120                         state = None;
 121                         setpath(path);
 122                 }
 123         }
 124         /* give up if we go too long without seeing the close */
 125         *pn = n;
 126         if(state == None || p-(buf+start) >= 2048)
 127                 return (p - buf);
 128         else
 129                 return start;
 130 }
 131
 132 static void
 133 catchint(void*, char *msg)
 134 {
 135         if(strstr(msg, "interrupt"))
 136                 noted(NCONT);
 137         else if(strstr(msg, "kill"))
 138                 noted(NDFLT);
 139         else
 140                 noted(NCONT);
 141 }
 142
 143 void
 144 main(int argc, char **argv)
 145 {
 146         char buf[4096];
 147         int n, m;
 148
 149         notify(catchint);
 150
 151         ARGBEGIN{
 152         default:
 153                 usage();
 154         }ARGEND
 155
 156         if(argc > 1)
 157                 usage();
 158         if(argc == 1)
 159                 prog = argv[0];
 160
 161         save();
 162         n = 0;
 163         for(;;){
 164                 m = read(0, buf+n, sizeof buf-n);
 165                 if(m < 0){
 166                         rerrstr(buf, sizeof buf);
 167                         if(strstr(buf, "interrupt"))
 168                                 continue;
 169                         break;
 170                 }
 171                 n += m;
 172                 m = process(buf, n, &n);
 173                 if(m > 0){
 174                         write(1, buf, m);
 175                         memmove(buf, buf+m, n-m);
 176                         n -= m;
 177                 }
 178         }
 179         rest();
 180         exits(nil);
 181 }