mdw@git.distorted.org.uk Git - adns/blob - src/setup.c

   1 /*
   2  * setup.c
   3  * - configuration file parsing
   4  * - management of global state
   5  */
   6 /*
   7  *  This file is part of adns, which is
   8  *    Copyright (C) 1997-2000,2003,2006  Ian Jackson
   9  *    Copyright (C) 1999-2000,2003,2006  Tony Finch
  10  *    Copyright (C) 1991 Massachusetts Institute of Technology
  11  *  (See the file INSTALL for full details.)
  12  *
  13  *  This program is free software; you can redistribute it and/or modify
  14  *  it under the terms of the GNU General Public License as published by
  15  *  the Free Software Foundation; either version 2, or (at your option)
  16  *  any later version.
  17  *
  18  *  This program is distributed in the hope that it will be useful,
  19  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  *  GNU General Public License for more details.
  22  *
  23  *  You should have received a copy of the GNU General Public License
  24  *  along with this program; if not, write to the Free Software Foundation,
  25  *  Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  26  */
  27
  28 #include <stdlib.h>
  29 #include <errno.h>
  30 #include <limits.h>
  31 #include <unistd.h>
  32 #include <fcntl.h>
  33
  34 #include <sys/types.h>
  35 #include <netdb.h>
  36 #include <sys/socket.h>
  37 #include <netinet/in.h>
  38 #include <arpa/inet.h>
  39
  40 #include "internal.h"
  41
  42 static void readconfig(adns_state ads, const char *filename, int warnmissing);
  43
  44 static void addserver(adns_state ads, const struct sockaddr *sa, int n) {
  45   int i;
  46   adns_rr_addr *ss;
  47   char buf[ADNS_ADDR2TEXT_BUFLEN];
  48
  49   if (sa->sa_family != AF_INET) {
  50     adns__debug(ads,-1,0,"non-IPv4 nameserver %s ignored",
  51                 adns__sockaddr_ntoa(sa, buf));
  52     return;
  53   }
  54
  55   for (i=0; i<ads->nservers; i++) {
  56     if (adns__sockaddr_equal_p(sa, &ads->servers[i].addr.sa)) {
  57       adns__debug(ads,-1,0,"duplicate nameserver %s ignored",
  58                   adns__sockaddr_ntoa(sa, buf));
  59       return;
  60     }
  61   }
  62
  63   if (ads->nservers>=MAXSERVERS) {
  64     adns__diag(ads,-1,0,"too many nameservers, ignoring %s",
  65                adns__sockaddr_ntoa(sa, buf));
  66     return;
  67   }
  68
  69   ss= ads->servers+ads->nservers;
  70   assert(n <= sizeof(ss->addr));
  71   ss->len = n;
  72   memcpy(&ss->addr, sa, n);
  73   ads->nservers++;
  74 }
  75
  76 static void freesearchlist(adns_state ads) {
  77   if (ads->nsearchlist) free(*ads->searchlist);
  78   free(ads->searchlist);
  79 }
  80
  81 static void saveerr(adns_state ads, int en) {
  82   if (!ads->configerrno) ads->configerrno= en;
  83 }
  84
  85 static void configparseerr(adns_state ads, const char *fn, int lno,
  86                            const char *fmt, ...) {
  87   va_list al;
  88
  89   saveerr(ads,EINVAL);
  90   if (!ads->logfn || (ads->iflags & adns_if_noerrprint)) return;
  91
  92   if (lno==-1) adns__lprintf(ads,"adns: %s: ",fn);
  93   else adns__lprintf(ads,"adns: %s:%d: ",fn,lno);
  94   va_start(al,fmt);
  95   adns__vlprintf(ads,fmt,al);
  96   va_end(al);
  97   adns__lprintf(ads,"\n");
  98 }
  99
 100 static int nextword(const char **bufp_io, const char **word_r, int *l_r) {
 101   const char *p, *q;
 102
 103   p= *bufp_io;
 104   while (ctype_whitespace(*p)) p++;
 105   if (!*p) return 0;
 106
 107   q= p;
 108   while (*q && !ctype_whitespace(*q)) q++;
 109
 110   *l_r= q-p;
 111   *word_r= p;
 112   *bufp_io= q;
 113
 114   return 1;
 115 }
 116
 117 static void ccf_nameserver(adns_state ads, const char *fn,
 118                            int lno, const char *buf) {
 119   adns_rr_addr a;
 120   char addrbuf[ADNS_ADDR2TEXT_BUFLEN];
 121   int err;
 122
 123   a.len= sizeof(a.addr);
 124   err= adns_text2addr(buf,DNS_PORT, 0, &a.addr.sa,&a.len);
 125   switch (err) {
 126   case 0:
 127     break;
 128   case EINVAL:
 129     configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf);
 130     return;
 131   default:
 132     configparseerr(ads,fn,lno,"failed to parse nameserver address `%s': %s",
 133                    buf,strerror(err));
 134     return;
 135   }
 136   adns__debug(ads,-1,0,"using nameserver %s",
 137               adns__sockaddr_ntoa(&a.addr.sa, addrbuf));
 138   addserver(ads,&a.addr.sa,a.len);
 139 }
 140
 141 static void ccf_search(adns_state ads, const char *fn,
 142                        int lno, const char *buf) {
 143   const char *bufp, *word;
 144   char *newchars, **newptrs, **pp;
 145   int count, tl, l;
 146
 147   if (!buf) return;
 148
 149   bufp= buf;
 150   count= 0;
 151   tl= 0;
 152   while (nextword(&bufp,&word,&l)) { count++; tl += l+1; }
 153
 154   newptrs= malloc(sizeof(char*)*count);
 155   if (!newptrs) { saveerr(ads,errno); return; }
 156
 157   newchars= malloc(tl);
 158   if (!newchars) { saveerr(ads,errno); free(newptrs); return; }
 159
 160   bufp= buf;
 161   pp= newptrs;
 162   while (nextword(&bufp,&word,&l)) {
 163     *pp++= newchars;
 164     memcpy(newchars,word,l);
 165     newchars += l;
 166     *newchars++ = 0;
 167   }
 168
 169   freesearchlist(ads);
 170   ads->nsearchlist= count;
 171   ads->searchlist= newptrs;
 172 }
 173
 174 static int gen_pton(const char *text, int *af_io, union gen_addr *a) {
 175   adns_rr_addr addr;
 176   int err;
 177
 178   addr.len= sizeof(addr.addr);
 179   err= adns_text2addr(text,0, adns_qf_addrlit_scope_forbid,
 180                       &addr.addr.sa, &addr.len);
 181   if (err) { assert(err == EINVAL); return 0; }
 182   if (*af_io == AF_UNSPEC) *af_io= addr.addr.sa.sa_family;
 183   else if (*af_io != addr.addr.sa.sa_family) return 0;
 184   adns__sockaddr_extract(&addr.addr.sa, a, 0);
 185   return 1;
 186 }
 187
 188 static void ccf_sortlist(adns_state ads, const char *fn,
 189                          int lno, const char *buf) {
 190   const char *word;
 191   char tbuf[200], *slash, *ep;
 192   const char *maskwhat;
 193   struct sortlist *sl;
 194   int l;
 195   int af;
 196   int initial= -1;
 197
 198   if (!buf) return;
 199
 200   ads->nsortlist= 0;
 201   while (nextword(&buf,&word,&l)) {
 202     if (ads->nsortlist >= MAXSORTLIST) {
 203       adns__diag(ads,-1,0,"too many sortlist entries,"
 204                  " ignoring %.*s onwards",l,word);
 205       return;
 206     }
 207
 208     if (l >= sizeof(tbuf)) {
 209       configparseerr(ads,fn,lno,"sortlist entry `%.*s' too long",l,word);
 210       continue;
 211     }
 212
 213     memcpy(tbuf,word,l); tbuf[l]= 0;
 214     slash= strchr(tbuf,'/');
 215     if (slash) *slash++= 0;
 216
 217     sl= &ads->sortlist[ads->nsortlist];
 218     af= AF_UNSPEC;
 219     if (!gen_pton(tbuf, &af, &sl->base)) {
 220       configparseerr(ads,fn,lno,"invalid address `%s' in sortlist",tbuf);
 221       continue;
 222     }
 223
 224     if (slash) {
 225       if (slash[strspn(slash, "0123456789")]) {
 226         maskwhat = "mask";
 227         if (!gen_pton(slash,&af,&sl->mask)) {
 228           configparseerr(ads,fn,lno,"invalid mask `%s' in sortlist",slash);
 229           continue;
 230         }
 231       } else {
 232         maskwhat = "prefix length";
 233         initial= strtoul(slash,&ep,10);
 234         if (*ep || initial>adns__addr_width(af)) {
 235           configparseerr(ads,fn,lno,"mask length `%s' invalid",slash);
 236           continue;
 237         }
 238         adns__prefix_mask(af, initial, &sl->mask);
 239       }
 240     } else {
 241       maskwhat = "implied prefix length";
 242       initial= adns__guess_prefix_length(af, &sl->base);
 243       if (initial < 0) {
 244         configparseerr(ads,fn,lno, "network address `%s'"
 245                        " in sortlist is not in classed ranges,"
 246                        " must specify mask explicitly", tbuf);
 247         continue;
 248       }
 249       adns__prefix_mask(af, initial, &sl->mask);
 250     }
 251
 252     if (!adns__addr_match_p(af,&sl->base, af,&sl->base,&sl->mask)) {
 253       if (initial >= 0) {
 254         configparseerr(ads,fn,lno, "%s %d in sortlist"
 255                        " overlaps address `%s'",maskwhat,initial,tbuf);
 256       } else {
 257         configparseerr(ads,fn,lno, "%s `%s' in sortlist"
 258                        " overlaps address `%s'",maskwhat,slash,tbuf);
 259       }
 260       continue;
 261     }
 262
 263     sl->af= af;
 264     ads->nsortlist++;
 265   }
 266 }
 267
 268 static void ccf_options(adns_state ads, const char *fn,
 269                         int lno, const char *buf) {
 270   const char *word;
 271   char *ep;
 272   unsigned long v;
 273   int l;
 274
 275   if (!buf) return;
 276
 277   while (nextword(&buf,&word,&l)) {
 278     if (l==5 && !memcmp(word,"debug",5)) {
 279       ads->iflags |= adns_if_debug;
 280       continue;
 281     }
 282     if (l>=6 && !memcmp(word,"ndots:",6)) {
 283       v= strtoul(word+6,&ep,10);
 284       if (l==6 || ep != word+l || v > INT_MAX) {
 285         configparseerr(ads,fn,lno,"option `%.*s' malformed"
 286                        " or has bad value",l,word);
 287         continue;
 288       }
 289       ads->searchndots= v;
 290       continue;
 291     }
 292     if (l>=12 && !memcmp(word,"adns_checkc:",12)) {
 293       if (!strcmp(word+12,"none")) {
 294         ads->iflags &= ~adns_if_checkc_freq;
 295         ads->iflags |= adns_if_checkc_entex;
 296       } else if (!strcmp(word+12,"entex")) {
 297         ads->iflags &= ~adns_if_checkc_freq;
 298         ads->iflags |= adns_if_checkc_entex;
 299       } else if (!strcmp(word+12,"freq")) {
 300         ads->iflags |= adns_if_checkc_freq;
 301       } else {
 302         configparseerr(ads,fn,lno, "option adns_checkc has bad value `%s' "
 303                        "(must be none, entex or freq", word+12);
 304       }
 305       continue;
 306     }
 307     adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,word);
 308   }
 309 }
 310
 311 static void ccf_clearnss(adns_state ads, const char *fn,
 312                          int lno, const char *buf) {
 313   ads->nservers= 0;
 314 }
 315
 316 static void ccf_include(adns_state ads, const char *fn,
 317                         int lno, const char *buf) {
 318   if (!*buf) {
 319     configparseerr(ads,fn,lno,"`include' directive with no filename");
 320     return;
 321   }
 322   readconfig(ads,buf,1);
 323 }
 324
 325 static void ccf_lookup(adns_state ads, const char *fn, int lno,
 326                        const char *buf) {
 327   int found_bind=0;
 328   const char *word;
 329   int l;
 330
 331   if (!*buf) {
 332     configparseerr(ads,fn,lno,"`lookup' directive with no databases");
 333     return;
 334   }
 335
 336   while (nextword(&buf,&word,&l)) {
 337     if (l==4 && !memcmp(word,"bind",4)) {
 338       found_bind=1;
 339     } else if (l==4 && !memcmp(word,"file",4)) {
 340       /* ignore this and hope /etc/hosts is not essential */
 341     } else if (l==2 && !memcmp(word,"yp",2)) {
 342       adns__diag(ads,-1,0,"%s:%d: yp lookups not supported by adns", fn,lno);
 343       found_bind=-1;
 344     } else {
 345       adns__diag(ads,-1,0,"%s:%d: unknown `lookup' database `%.*s'",
 346                  fn,lno, l,word);
 347       found_bind=-1;
 348     }
 349   }
 350   if (!found_bind)
 351     adns__diag(ads,-1,0,"%s:%d: `lookup' specified, but not `bind'", fn,lno);
 352 }
 353
 354 static const struct configcommandinfo {
 355   const char *name;
 356   void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
 357 } configcommandinfos[]= {
 358   { "nameserver",        ccf_nameserver  },
 359   { "domain",            ccf_search      },
 360   { "search",            ccf_search      },
 361   { "sortlist",          ccf_sortlist    },
 362   { "options",           ccf_options     },
 363   { "clearnameservers",  ccf_clearnss    },
 364   { "include",           ccf_include     },
 365   { "lookup",            ccf_lookup      }, /* OpenBSD */
 366   {  0                                   }
 367 };
 368
 369 typedef union {
 370   FILE *file;
 371   const char *text;
 372 } getline_ctx;
 373
 374 static int gl_file(adns_state ads, getline_ctx *src_io, const char *filename,
 375                    int lno, char *buf, int buflen) {
 376   FILE *file= src_io->file;
 377   int c, i;
 378   char *p;
 379
 380   p= buf;
 381   buflen--;
 382   i= 0;
 383
 384   for (;;) { /* loop over chars */
 385     if (i == buflen) {
 386       adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
 387       goto x_badline;
 388     }
 389     c= getc(file);
 390     if (!c) {
 391       adns__diag(ads,-1,0,"%s:%d: line contains nul, ignored",filename,lno);
 392       goto x_badline;
 393     } else if (c == '\n') {
 394       break;
 395     } else if (c == EOF) {
 396       if (ferror(file)) {
 397         saveerr(ads,errno);
 398         adns__diag(ads,-1,0,"%s:%d: read error: %s",
 399                    filename,lno,strerror(errno));
 400         return -1;
 401       }
 402       if (!i) return -1;
 403       break;
 404     } else {
 405       *p++= c;
 406       i++;
 407     }
 408   }
 409
 410   *p++= 0;
 411   return i;
 412
 413  x_badline:
 414   saveerr(ads,EINVAL);
 415   while ((c= getc(file)) != EOF && c != '\n');
 416   return -2;
 417 }
 418
 419 static int gl_text(adns_state ads, getline_ctx *src_io, const char *filename,
 420                    int lno, char *buf, int buflen) {
 421   const char *cp= src_io->text;
 422   int l;
 423
 424   if (!cp || !*cp) return -1;
 425
 426   if (*cp == ';' || *cp == '\n') cp++;
 427   l= strcspn(cp,";\n");
 428   src_io->text = cp+l;
 429
 430   if (l >= buflen) {
 431     adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
 432     saveerr(ads,EINVAL);
 433     return -2;
 434   }
 435
 436   memcpy(buf,cp,l);
 437   buf[l]= 0;
 438   return l;
 439 }
 440
 441 static void readconfiggeneric(adns_state ads, const char *filename,
 442                               int (*getline)(adns_state ads, getline_ctx*,
 443                                              const char *filename, int lno,
 444                                              char *buf, int buflen),
 445                               /* Returns >=0 for success, -1 for EOF or error
 446                                * (error will have been reported), or -2 for
 447                                * bad line was encountered, try again.
 448                                */
 449                               getline_ctx gl_ctx) {
 450   char linebuf[2000], *p, *q;
 451   int lno, l, dirl;
 452   const struct configcommandinfo *ccip;
 453
 454   for (lno=1;
 455        (l= getline(ads,&gl_ctx, filename,lno, linebuf,sizeof(linebuf))) != -1;
 456        lno++) {
 457     if (l == -2) continue;
 458     while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
 459     linebuf[l]= 0;
 460     p= linebuf;
 461     while (ctype_whitespace(*p)) p++;
 462     if (*p == '#' || *p == ';' || !*p) continue;
 463     q= p;
 464     while (*q && !ctype_whitespace(*q)) q++;
 465     dirl= q-p;
 466     for (ccip=configcommandinfos;
 467          ccip->name &&
 468            !(strlen(ccip->name)==dirl && !memcmp(ccip->name,p,q-p));
 469          ccip++);
 470     if (!ccip->name) {
 471       adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'",
 472                  filename,lno,(int)(q-p),p);
 473       continue;
 474     }
 475     while (ctype_whitespace(*q)) q++;
 476     ccip->fn(ads,filename,lno,q);
 477   }
 478 }
 479
 480 static const char *instrum_getenv(adns_state ads, const char *envvar) {
 481   const char *value;
 482
 483   value= getenv(envvar);
 484   if (!value) adns__debug(ads,-1,0,"environment variable %s not set",envvar);
 485   else adns__debug(ads,-1,0,"environment variable %s"
 486                    " set to `%s'",envvar,value);
 487   return value;
 488 }
 489
 490 static void readconfig(adns_state ads, const char *filename, int warnmissing) {
 491   getline_ctx gl_ctx;
 492
 493   gl_ctx.file= fopen(filename,"r");
 494   if (!gl_ctx.file) {
 495     if (errno == ENOENT) {
 496       if (warnmissing)
 497         adns__debug(ads,-1,0, "configuration file"
 498                     " `%s' does not exist",filename);
 499       return;
 500     }
 501     saveerr(ads,errno);
 502     adns__diag(ads,-1,0,"cannot open configuration file `%s': %s",
 503                filename,strerror(errno));
 504     return;
 505   }
 506
 507   readconfiggeneric(ads,filename,gl_file,gl_ctx);
 508
 509   fclose(gl_ctx.file);
 510 }
 511
 512 static void readconfigtext(adns_state ads, const char *text,
 513                            const char *showname) {
 514   getline_ctx gl_ctx;
 515
 516   gl_ctx.text= text;
 517   readconfiggeneric(ads,showname,gl_text,gl_ctx);
 518 }
 519
 520 static void readconfigenv(adns_state ads, const char *envvar) {
 521   const char *filename;
 522
 523   if (ads->iflags & adns_if_noenv) {
 524     adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
 525     return;
 526   }
 527   filename= instrum_getenv(ads,envvar);
 528   if (filename) readconfig(ads,filename,1);
 529 }
 530
 531 static void readconfigenvtext(adns_state ads, const char *envvar) {
 532   const char *textdata;
 533
 534   if (ads->iflags & adns_if_noenv) {
 535     adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
 536     return;
 537   }
 538   textdata= instrum_getenv(ads,envvar);
 539   if (textdata) readconfigtext(ads,textdata,envvar);
 540 }
 541
 542
 543 int adns__setnonblock(adns_state ads, int fd) {
 544   int r;
 545
 546   r= fcntl(fd,F_GETFL,0); if (r<0) return errno;
 547   r |= O_NONBLOCK;
 548   r= fcntl(fd,F_SETFL,r); if (r<0) return errno;
 549   return 0;
 550 }
 551
 552 static int init_begin(adns_state *ads_r, adns_initflags flags,
 553                       adns_logcallbackfn *logfn, void *logfndata) {
 554   adns_state ads;
 555   pid_t pid;
 556
 557   ads= malloc(sizeof(*ads)); if (!ads) return errno;
 558
 559   ads->iflags= flags;
 560   ads->logfn= logfn;
 561   ads->logfndata= logfndata;
 562   ads->configerrno= 0;
 563   LIST_INIT(ads->udpw);
 564   LIST_INIT(ads->tcpw);
 565   LIST_INIT(ads->childw);
 566   LIST_INIT(ads->output);
 567   ads->forallnext= 0;
 568   ads->nextid= 0x311f;
 569   ads->udpsocket= ads->tcpsocket= -1;
 570   adns__vbuf_init(&ads->tcpsend);
 571   adns__vbuf_init(&ads->tcprecv);
 572   ads->tcprecv_skip= 0;
 573   ads->nservers= ads->nsortlist= ads->nsearchlist= ads->tcpserver= 0;
 574   ads->searchndots= 1;
 575   ads->tcpstate= server_disconnected;
 576   timerclear(&ads->tcptimeout);
 577   ads->searchlist= 0;
 578
 579   pid= getpid();
 580   ads->rand48xsubi[0]= pid;
 581   ads->rand48xsubi[1]= (unsigned long)pid >> 16;
 582   ads->rand48xsubi[2]= pid ^ ((unsigned long)pid >> 16);
 583
 584   *ads_r= ads;
 585   return 0;
 586 }
 587
 588 static int init_finish(adns_state ads) {
 589   struct sockaddr_in sin;
 590   struct protoent *proto;
 591   int i, r;
 592
 593   if (!ads->nservers) {
 594     if (ads->logfn && ads->iflags & adns_if_debug)
 595       adns__lprintf(ads,"adns: no nameservers, using IPv4 localhost\n");
 596     memset(&sin, 0, sizeof(sin));
 597     sin.sin_family = AF_INET;
 598     sin.sin_port = htons(DNS_PORT);
 599     sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 600     addserver(ads,(struct sockaddr *)&sin, sizeof(sin));
 601   }
 602
 603   /* we can't cope with multiple transport address families yet */
 604   for (i=0; i<ads->nservers; i++)
 605     assert(ads->servers[i].addr.sa.sa_family==AF_INET);
 606
 607   proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
 608   ads->udpsocket= socket(AF_INET,SOCK_DGRAM,proto->p_proto);
 609   if (ads->udpsocket<0) { r= errno; goto x_free; }
 610
 611   r= adns__setnonblock(ads,ads->udpsocket);
 612   if (r) { r= errno; goto x_closeudp; }
 613
 614   return 0;
 615
 616  x_closeudp:
 617   close(ads->udpsocket);
 618  x_free:
 619   free(ads);
 620   return r;
 621 }
 622
 623 static void init_abort(adns_state ads) {
 624   if (ads->nsearchlist) {
 625     free(ads->searchlist[0]);
 626     free(ads->searchlist);
 627   }
 628   free(ads);
 629 }
 630
 631 static void logfn_file(adns_state ads, void *logfndata,
 632                        const char *fmt, va_list al) {
 633   vfprintf(logfndata,fmt,al);
 634 }
 635
 636 static int init_files(adns_state *ads_r, adns_initflags flags,
 637                       adns_logcallbackfn *logfn, void *logfndata) {
 638   adns_state ads;
 639   const char *res_options, *adns_res_options;
 640   int r;
 641
 642   r= init_begin(&ads, flags, logfn, logfndata);
 643   if (r) return r;
 644
 645   res_options= instrum_getenv(ads,"RES_OPTIONS");
 646   adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
 647   ccf_options(ads,"RES_OPTIONS",-1,res_options);
 648   ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
 649
 650   readconfig(ads,"/etc/resolv.conf",1);
 651   readconfig(ads,"/etc/resolv-adns.conf",0);
 652   readconfigenv(ads,"RES_CONF");
 653   readconfigenv(ads,"ADNS_RES_CONF");
 654
 655   readconfigenvtext(ads,"RES_CONF_TEXT");
 656   readconfigenvtext(ads,"ADNS_RES_CONF_TEXT");
 657
 658   ccf_options(ads,"RES_OPTIONS",-1,res_options);
 659   ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
 660
 661   ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
 662   ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
 663
 664   if (ads->configerrno && ads->configerrno != EINVAL) {
 665     r= ads->configerrno;
 666     init_abort(ads);
 667     return r;
 668   }
 669
 670   r= init_finish(ads);
 671   if (r) return r;
 672
 673   adns__consistency(ads,0,cc_entex);
 674   *ads_r= ads;
 675   return 0;
 676 }
 677
 678 int adns_init(adns_state *ads_r, adns_initflags flags, FILE *diagfile) {
 679   return init_files(ads_r, flags, logfn_file, diagfile ? diagfile : stderr);
 680 }
 681
 682 static int init_strcfg(adns_state *ads_r, adns_initflags flags,
 683                        adns_logcallbackfn *logfn, void *logfndata,
 684                        const char *configtext) {
 685   adns_state ads;
 686   int r;
 687
 688   r= init_begin(&ads, flags, logfn, logfndata);
 689   if (r) return r;
 690
 691   readconfigtext(ads,configtext,"<supplied configuration text>");
 692   if (ads->configerrno) {
 693     r= ads->configerrno;
 694     init_abort(ads);
 695     return r;
 696   }
 697
 698   r= init_finish(ads);  if (r) return r;
 699   adns__consistency(ads,0,cc_entex);
 700   *ads_r= ads;
 701   return 0;
 702 }
 703
 704 int adns_init_strcfg(adns_state *ads_r, adns_initflags flags,
 705                      FILE *diagfile, const char *configtext) {
 706   return init_strcfg(ads_r, flags,
 707                      diagfile ? logfn_file : 0, diagfile,
 708                      configtext);
 709 }
 710
 711 int adns_init_logfn(adns_state *newstate_r, adns_initflags flags,
 712                     const char *configtext /*0=>use default config files*/,
 713                     adns_logcallbackfn *logfn /*0=>logfndata is a FILE* */,
 714                     void *logfndata /*0 with logfn==0 => discard*/) {
 715   if (!logfn && logfndata)
 716     logfn= logfn_file;
 717   if (configtext)
 718     return init_strcfg(newstate_r, flags, logfn, logfndata, configtext);
 719   else
 720     return init_files(newstate_r, flags, logfn, logfndata);
 721 }
 722
 723 void adns_finish(adns_state ads) {
 724   adns__consistency(ads,0,cc_entex);
 725   for (;;) {
 726     if (ads->udpw.head) adns_cancel(ads->udpw.head);
 727     else if (ads->tcpw.head) adns_cancel(ads->tcpw.head);
 728     else if (ads->childw.head) adns_cancel(ads->childw.head);
 729     else if (ads->output.head) adns_cancel(ads->output.head);
 730     else break;
 731   }
 732   close(ads->udpsocket);
 733   if (ads->tcpsocket >= 0) close(ads->tcpsocket);
 734   adns__vbuf_free(&ads->tcpsend);
 735   adns__vbuf_free(&ads->tcprecv);
 736   freesearchlist(ads);
 737   free(ads);
 738 }
 739
 740 void adns_forallqueries_begin(adns_state ads) {
 741   adns__consistency(ads,0,cc_entex);
 742   ads->forallnext=
 743     ads->udpw.head ? ads->udpw.head :
 744     ads->tcpw.head ? ads->tcpw.head :
 745     ads->childw.head ? ads->childw.head :
 746     ads->output.head;
 747 }
 748
 749 adns_query adns_forallqueries_next(adns_state ads, void **context_r) {
 750   adns_query qu, nqu;
 751
 752   adns__consistency(ads,0,cc_entex);
 753   nqu= ads->forallnext;
 754   for (;;) {
 755     qu= nqu;
 756     if (!qu) return 0;
 757     if (qu->next) {
 758       nqu= qu->next;
 759     } else if (qu == ads->udpw.tail) {
 760       nqu=
 761         ads->tcpw.head ? ads->tcpw.head :
 762         ads->childw.head ? ads->childw.head :
 763         ads->output.head;
 764     } else if (qu == ads->tcpw.tail) {
 765       nqu=
 766         ads->childw.head ? ads->childw.head :
 767         ads->output.head;
 768     } else if (qu == ads->childw.tail) {
 769       nqu= ads->output.head;
 770     } else {
 771       nqu= 0;
 772     }
 773     if (!qu->parent) break;
 774   }
 775   ads->forallnext= nqu;
 776   if (context_r) *context_r= qu->ctx.ext;
 777   return qu;
 778 }