ref: a2c0e55e6885fde0d135831a77d227bc933d89e7
dir: /sys/src/cmd/ndb/dnsgetip.c/
/* one-shot resolver */ #include <u.h> #include <libc.h> #include <bio.h> #include <ndb.h> #include "dns.h" Cfg cfg; char *dbfile; int debug = 0; char *logfile = "dnsgetip"; int maxage = 60*60; char mntpt[Maxpath]; int needrefresh = 0; ulong now = 0; vlong nowns = 0; int traceactivity = 0; char *zonerefreshprogram; int aflag = 0; int addresses = 0; char Ebotch[] = "dns botch"; char* resolve(char *name, int type) { int status; char *errmsg; Request req; RR *rr, *rp, *neg; status = Rok; errmsg = nil; memset(&req, 0, sizeof req); getactivity(&req, 0); req.isslave = 1; req.aborttime = NS2MS(nowns) + Maxreqtm; rr = dnresolve(name, Cin, type, &req, nil, 0, Recurse, 0, &status); neg = rrremneg(&rr); if(rr == nil || neg != nil){ if(neg != nil) status = neg->negrcode; errmsg = Ebotch; if(status > 0 && status < nrname) errmsg = rname[status]; } rrfreelist(neg); for(rp = rr; rp != nil; rp = rp->next){ print("%s\n", rp->ip->name); addresses++; if(!aflag) exits(nil); } rrfreelist(rr); return errmsg; } void usage(void) { fprint(2, "%s: [-adx] domain\n", argv0); exits("usage"); } void main(int argc, char **argv) { char *e4, *e6; strcpy(mntpt, "/net"); cfg.inside = 1; cfg.resolver = 1; ARGBEGIN{ case 'a': aflag = 1; break; case 'd': debug++; break; case 'x': strcpy(mntpt, "/net.alt"); break; default: usage(); }ARGEND if(argc != 1) usage(); if(strcmp(ipattr(*argv), "ip") == 0) print("%s\n", *argv); else { dninit(); e4 = resolve(*argv, Ta); e6 = resolve(*argv, Taaaa); if(addresses == 0){ if(e4 == e6) sysfatal("%s: dns failure: %s", *argv, e4); sysfatal("%s: dns failure: v4: %s: v6: %s", *argv, e4, e6); } } exits(nil); } RR* getdnsservers(int class) { return dnsservers(class); } /* stubs */ void syslog(int, char*, char*, ...){} void logreply(int, uchar*, DNSmsg*){} void logsend(int, int, uchar*, char*, char*, int){}