sys/src/cmd/ndb/query.c

   1 /*
   2  *  search the network database for matches
   3  */
   4 #include <u.h>
   5 #include <libc.h>
   6 #include <bio.h>
   7 #include <ndb.h>
   8
   9 static int all, multiple;
  10 static Biobuf bout;
  11
  12 void
  13 usage(void)
  14 {
  15         fprint(2, "usage: query [-am] [-f ndbfile] attr value "
  16                 "[returned-attr [reps]]\n");
  17         exits("usage");
  18 }
  19
  20 /* print values of nt's attributes matching rattr */
  21 static void
  22 prmatch(Ndbtuple *nt, char *rattr)
  23 {
  24         for(; nt; nt = nt->entry)
  25                 if (strcmp(nt->attr, rattr) == 0)
  26                         Bprint(&bout, "%s\n", nt->val);
  27 }
  28
  29 void
  30 search(Ndb *db, char *attr, char *val, char *rattr)
  31 {
  32         char *p;
  33         Ndbs s;
  34         Ndbtuple *t, *nt;
  35
  36         /* first entry with a matching rattr */
  37         if(rattr && !all){
  38                 p = ndbgetvalue(db, &s, attr, val, rattr, &t);
  39                 if (multiple)
  40                         prmatch(t, rattr);
  41                 else if(p)
  42                         Bprint(&bout, "%s\n", p);
  43                 ndbfree(t);
  44                 free(p);
  45                 return;
  46         }
  47
  48         /* all entries with matching rattrs */
  49         if(rattr) {
  50                 for(t = ndbsearch(db, &s, attr, val); t != nil;
  51                     t = ndbsnext(&s, attr, val)){
  52                         prmatch(t, rattr);
  53                         ndbfree(t);
  54                 }
  55                 return;
  56         }
  57
  58         /* all entries */
  59         for(t = ndbsearch(db, &s, attr, val); t; t = ndbsnext(&s, attr, val)){
  60                 for(nt = t; nt; nt = nt->entry)
  61                         Bprint(&bout, "%s=%s ", nt->attr, nt->val);
  62                 Bprint(&bout, "\n");
  63                 ndbfree(t);
  64         }
  65 }
  66
  67 void
  68 main(int argc, char **argv)
  69 {
  70         int reps = 1;
  71         char *rattr = nil, *dbfile = nil;
  72         Ndb *db;
  73
  74         ARGBEGIN{
  75         case 'a':
  76                 all++;
  77                 break;
  78         case 'm':
  79                 multiple++;
  80                 break;
  81         case 'f':
  82                 dbfile = EARGF(usage());
  83                 break;
  84         default:
  85                 usage();
  86         }ARGEND;
  87
  88         switch(argc){
  89         case 4:
  90                 reps = atoi(argv[3]);   /* wtf use is this? */
  91                 /* fall through */
  92         case 3:
  93                 rattr = argv[2];
  94                 break;
  95         case 2:
  96                 rattr = nil;
  97                 break;
  98         default:
  99                 usage();
 100         }
 101
 102         if(Binit(&bout, 1, OWRITE) == -1)
 103                 sysfatal("Binit: %r");
 104         db = ndbopen(dbfile);
 105         if(db == nil){
 106                 fprint(2, "%s: no db files\n", argv0);
 107                 exits("no db");
 108         }
 109         while(reps--)
 110                 search(db, argv[0], argv[1], rattr);
 111         ndbclose(db);
 112
 113         exits(0);
 114 }