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   for (i=0; i<ads->nservers; i++) {
  50     if (adns__sockaddr_equal_p(sa, &ads->servers[i].addr.sa)) {
  51       adns__debug(ads,-1,0,"duplicate nameserver %s ignored",
  52                   adns__sockaddr_ntoa(sa, buf));
  53       return;
  54     }
  55   }
  56
  57   if (ads->nservers>=MAXSERVERS) {
  58     adns__diag(ads,-1,0,"too many nameservers, ignoring %s",
  59                adns__sockaddr_ntoa(sa, buf));
  60     return;
  61   }
  62
  63   ss= ads->servers+ads->nservers;
  64   assert(n <= sizeof(ss->addr));
  65   ss->len = n;
  66   memcpy(&ss->addr, sa, n);
  67   ads->nservers++;
  68 }
  69
  70 static void freesearchlist(adns_state ads) {
  71   if (ads->nsearchlist) free(*ads->searchlist);
  72   free(ads->searchlist);
  73 }
  74
  75 static void saveerr(adns_state ads, int en) {
  76   if (!ads->configerrno) ads->configerrno= en;
  77 }
  78
  79 static void configparseerr(adns_state ads, const char *fn, int lno,
  80                            const char *fmt, ...) {
  81   va_list al;
  82
  83   saveerr(ads,EINVAL);
  84   if (!ads->logfn || (ads->iflags & adns_if_noerrprint)) return;
  85
  86   if (lno==-1) adns__lprintf(ads,"adns: %s: ",fn);
  87   else adns__lprintf(ads,"adns: %s:%d: ",fn,lno);
  88   va_start(al,fmt);
  89   adns__vlprintf(ads,fmt,al);
  90   va_end(al);
  91   adns__lprintf(ads,"\n");
  92 }
  93
  94 static int nextword(const char **bufp_io, const char **word_r, int *l_r) {
  95   const char *p, *q;
  96
  97   p= *bufp_io;
  98   while (ctype_whitespace(*p)) p++;
  99   if (!*p) return 0;
 100
 101   q= p;
 102   while (*q && !ctype_whitespace(*q)) q++;
 103
 104   *l_r= q-p;
 105   *word_r= p;
 106   *bufp_io= q;
 107
 108   return 1;
 109 }
 110
 111 static void ccf_nameserver(adns_state ads, const char *fn,
 112                            int lno, const char *buf) {
 113   adns_rr_addr a;
 114   char addrbuf[ADNS_ADDR2TEXT_BUFLEN];
 115   int err;
 116
 117   a.len= sizeof(a.addr);
 118   err= adns_text2addr(buf,DNS_PORT, 0, &a.addr.sa,&a.len);
 119   switch (err) {
 120   case 0:
 121     break;
 122   case EINVAL:
 123     configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf);
 124     return;
 125   default:
 126     configparseerr(ads,fn,lno,"failed to parse nameserver address `%s': %s",
 127                    buf,strerror(err));
 128     return;
 129   }
 130   adns__debug(ads,-1,0,"using nameserver %s",
 131               adns__sockaddr_ntoa(&a.addr.sa, addrbuf));
 132   addserver(ads,&a.addr.sa,a.len);
 133 }
 134
 135 static void ccf_search(adns_state ads, const char *fn,
 136                        int lno, const char *buf) {
 137   const char *bufp, *word;
 138   char *newchars, **newptrs, **pp;
 139   int count, tl, l;
 140
 141   if (!buf) return;
 142
 143   bufp= buf;
 144   count= 0;
 145   tl= 0;
 146   while (nextword(&bufp,&word,&l)) { count++; tl += l+1; }
 147
 148   newptrs= malloc(sizeof(char*)*count);
 149   if (!newptrs) { saveerr(ads,errno); return; }
 150
 151   newchars= malloc(tl);
 152   if (!newchars) { saveerr(ads,errno); free(newptrs); return; }
 153
 154   bufp= buf;
 155   pp= newptrs;
 156   while (nextword(&bufp,&word,&l)) {
 157     *pp++= newchars;
 158     memcpy(newchars,word,l);
 159     newchars += l;
 160     *newchars++ = 0;
 161   }
 162
 163   freesearchlist(ads);
 164   ads->nsearchlist= count;
 165   ads->searchlist= newptrs;
 166 }
 167
 168 static int gen_pton(const char *text, int *af_io, union gen_addr *a) {
 169   adns_rr_addr addr;
 170   int err;
 171
 172   addr.len= sizeof(addr.addr);
 173   err= adns_text2addr(text,0, adns_qf_addrlit_scope_forbid,
 174                       &addr.addr.sa, &addr.len);
 175   if (err) { assert(err == EINVAL); return 0; }
 176   if (*af_io == AF_UNSPEC) *af_io= addr.addr.sa.sa_family;
 177   else if (*af_io != addr.addr.sa.sa_family) return 0;
 178   adns__sockaddr_extract(&addr.addr.sa, a, 0);
 179   return 1;
 180 }
 181
 182 static void ccf_sortlist(adns_state ads, const char *fn,
 183                          int lno, const char *buf) {
 184   const char *word;
 185   char tbuf[200], *slash, *ep;
 186   const char *maskwhat;
 187   struct sortlist *sl;
 188   int l;
 189   int af;
 190   int initial= -1;
 191
 192   if (!buf) return;
 193
 194   ads->nsortlist= 0;
 195   while (nextword(&buf,&word,&l)) {
 196     if (ads->nsortlist >= MAXSORTLIST) {
 197       adns__diag(ads,-1,0,"too many sortlist entries,"
 198                  " ignoring %.*s onwards",l,word);
 199       return;
 200     }
 201
 202     if (l >= sizeof(tbuf)) {
 203       configparseerr(ads,fn,lno,"sortlist entry `%.*s' too long",l,word);
 204       continue;
 205     }
 206
 207     memcpy(tbuf,word,l); tbuf[l]= 0;
 208     slash= strchr(tbuf,'/');
 209     if (slash) *slash++= 0;
 210
 211     sl= &ads->sortlist[ads->nsortlist];
 212     af= AF_UNSPEC;
 213     if (!gen_pton(tbuf, &af, &sl->base)) {
 214       configparseerr(ads,fn,lno,"invalid address `%s' in sortlist",tbuf);
 215       continue;
 216     }
 217
 218     if (slash) {
 219       if (slash[strspn(slash, "0123456789")]) {
 220         maskwhat = "mask";
 221         if (!gen_pton(slash,&af,&sl->mask)) {
 222           configparseerr(ads,fn,lno,"invalid mask `%s' in sortlist",slash);
 223           continue;
 224         }
 225       } else {
 226         maskwhat = "prefix length";
 227         initial= strtoul(slash,&ep,10);
 228         if (*ep || initial>adns__addr_width(af)) {
 229           configparseerr(ads,fn,lno,"mask length `%s' invalid",slash);
 230           continue;
 231         }
 232         adns__prefix_mask(af, initial, &sl->mask);
 233       }
 234     } else {
 235       maskwhat = "implied prefix length";
 236       initial= adns__guess_prefix_length(af, &sl->base);
 237       if (initial < 0) {
 238         configparseerr(ads,fn,lno, "network address `%s'"
 239                        " in sortlist is not in classed ranges,"
 240                        " must specify mask explicitly", tbuf);
 241         continue;
 242       }
 243       adns__prefix_mask(af, initial, &sl->mask);
 244     }
 245
 246     if (!adns__addr_match_p(af,&sl->base, af,&sl->base,&sl->mask)) {
 247       if (initial >= 0) {
 248         configparseerr(ads,fn,lno, "%s %d in sortlist"
 249                        " overlaps address `%s'",maskwhat,initial,tbuf);
 250       } else {
 251         configparseerr(ads,fn,lno, "%s `%s' in sortlist"
 252                        " overlaps address `%s'",maskwhat,slash,tbuf);
 253       }
 254       continue;
 255     }
 256
 257     sl->af= af;
 258     ads->nsortlist++;
 259   }
 260 }
 261
 262 static void ccf_options(adns_state ads, const char *fn,
 263                         int lno, const char *buf) {
 264   const char *word;
 265   char *ep;
 266   unsigned long v;
 267   int l;
 268
 269   if (!buf) return;
 270
 271   while (nextword(&buf,&word,&l)) {
 272     if (l==5 && !memcmp(word,"debug",5)) {
 273       ads->iflags |= adns_if_debug;
 274       continue;
 275     }
 276     if (l>=6 && !memcmp(word,"ndots:",6)) {
 277       v= strtoul(word+6,&ep,10);
 278       if (l==6 || ep != word+l || v > INT_MAX) {
 279         configparseerr(ads,fn,lno,"option `%.*s' malformed"
 280                        " or has bad value",l,word);
 281         continue;
 282       }
 283       ads->searchndots= v;
 284       continue;
 285     }
 286     if (l>=12 && !memcmp(word,"adns_checkc:",12)) {
 287       if (!strcmp(word+12,"none")) {
 288         ads->iflags &= ~adns_if_checkc_freq;
 289         ads->iflags |= adns_if_checkc_entex;
 290       } else if (!strcmp(word+12,"entex")) {
 291         ads->iflags &= ~adns_if_checkc_freq;
 292         ads->iflags |= adns_if_checkc_entex;
 293       } else if (!strcmp(word+12,"freq")) {
 294         ads->iflags |= adns_if_checkc_freq;
 295       } else {
 296         configparseerr(ads,fn,lno, "option adns_checkc has bad value `%s' "
 297                        "(must be none, entex or freq", word+12);
 298       }
 299       continue;
 300     }
 301     adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,word);
 302   }
 303 }
 304
 305 static void ccf_clearnss(adns_state ads, const char *fn,
 306                          int lno, const char *buf) {
 307   ads->nservers= 0;
 308 }
 309
 310 static void ccf_include(adns_state ads, const char *fn,
 311                         int lno, const char *buf) {
 312   if (!*buf) {
 313     configparseerr(ads,fn,lno,"`include' directive with no filename");
 314     return;
 315   }
 316   readconfig(ads,buf,1);
 317 }
 318
 319 static void ccf_lookup(adns_state ads, const char *fn, int lno,
 320                        const char *buf) {
 321   int found_bind=0;
 322   const char *word;
 323   int l;
 324
 325   if (!*buf) {
 326     configparseerr(ads,fn,lno,"`lookup' directive with no databases");
 327     return;
 328   }
 329
 330   while (nextword(&buf,&word,&l)) {
 331     if (l==4 && !memcmp(word,"bind",4)) {
 332       found_bind=1;
 333     } else if (l==4 && !memcmp(word,"file",4)) {
 334       /* ignore this and hope /etc/hosts is not essential */
 335     } else if (l==2 && !memcmp(word,"yp",2)) {
 336       adns__diag(ads,-1,0,"%s:%d: yp lookups not supported by adns", fn,lno);
 337       found_bind=-1;
 338     } else {
 339       adns__diag(ads,-1,0,"%s:%d: unknown `lookup' database `%.*s'",
 340                  fn,lno, l,word);
 341       found_bind=-1;
 342     }
 343   }
 344   if (!found_bind)
 345     adns__diag(ads,-1,0,"%s:%d: `lookup' specified, but not `bind'", fn,lno);
 346 }
 347
 348 static const struct configcommandinfo {
 349   const char *name;
 350   void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
 351 } configcommandinfos[]= {
 352   { "nameserver",        ccf_nameserver  },
 353   { "domain",            ccf_search      },
 354   { "search",            ccf_search      },
 355   { "sortlist",          ccf_sortlist    },
 356   { "options",           ccf_options     },
 357   { "clearnameservers",  ccf_clearnss    },
 358   { "include",           ccf_include     },
 359   { "lookup",            ccf_lookup      }, /* OpenBSD */
 360   {  0                                   }
 361 };
 362
 363 typedef union {
 364   FILE *file;
 365   const char *text;
 366 } getline_ctx;
 367
 368 static int gl_file(adns_state ads, getline_ctx *src_io, const char *filename,
 369                    int lno, char *buf, int buflen) {
 370   FILE *file= src_io->file;
 371   int c, i;
 372   char *p;
 373
 374   p= buf;
 375   buflen--;
 376   i= 0;
 377
 378   for (;;) { /* loop over chars */
 379     if (i == buflen) {
 380       adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
 381       goto x_badline;
 382     }
 383     c= getc(file);
 384     if (!c) {
 385       adns__diag(ads,-1,0,"%s:%d: line contains nul, ignored",filename,lno);
 386       goto x_badline;
 387     } else if (c == '\n') {
 388       break;
 389     } else if (c == EOF) {
 390       if (ferror(file)) {
 391         saveerr(ads,errno);
 392         adns__diag(ads,-1,0,"%s:%d: read error: %s",
 393                    filename,lno,strerror(errno));
 394         return -1;
 395       }
 396       if (!i) return -1;
 397       break;
 398     } else {
 399       *p++= c;
 400       i++;
 401     }
 402   }
 403
 404   *p++= 0;
 405   return i;
 406
 407  x_badline:
 408   saveerr(ads,EINVAL);
 409   while ((c= getc(file)) != EOF && c != '\n');
 410   return -2;
 411 }
 412
 413 static int gl_text(adns_state ads, getline_ctx *src_io, const char *filename,
 414                    int lno, char *buf, int buflen) {
 415   const char *cp= src_io->text;
 416   int l;
 417
 418   if (!cp || !*cp) return -1;
 419
 420   if (*cp == ';' || *cp == '\n') cp++;
 421   l= strcspn(cp,";\n");
 422   src_io->text = cp+l;
 423
 424   if (l >= buflen) {
 425     adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
 426     saveerr(ads,EINVAL);
 427     return -2;
 428   }
 429
 430   memcpy(buf,cp,l);
 431   buf[l]= 0;
 432   return l;
 433 }
 434
 435 static void readconfiggeneric(adns_state ads, const char *filename,
 436                               int (*getline)(adns_state ads, getline_ctx*,
 437                                              const char *filename, int lno,
 438                                              char *buf, int buflen),
 439                               /* Returns >=0 for success, -1 for EOF or error
 440                                * (error will have been reported), or -2 for
 441                                * bad line was encountered, try again.
 442                                */
 443                               getline_ctx gl_ctx) {
 444   char linebuf[2000], *p, *q;
 445   int lno, l, dirl;
 446   const struct configcommandinfo *ccip;
 447
 448   for (lno=1;
 449        (l= getline(ads,&gl_ctx, filename,lno, linebuf,sizeof(linebuf))) != -1;
 450        lno++) {
 451     if (l == -2) continue;
 452     while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
 453     linebuf[l]= 0;
 454     p= linebuf;
 455     while (ctype_whitespace(*p)) p++;
 456     if (*p == '#' || *p == ';' || !*p) continue;
 457     q= p;
 458     while (*q && !ctype_whitespace(*q)) q++;
 459     dirl= q-p;
 460     for (ccip=configcommandinfos;
 461          ccip->name &&
 462            !(strlen(ccip->name)==dirl && !memcmp(ccip->name,p,q-p));
 463          ccip++);
 464     if (!ccip->name) {
 465       adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'",
 466                  filename,lno,(int)(q-p),p);
 467       continue;
 468     }
 469     while (ctype_whitespace(*q)) q++;
 470     ccip->fn(ads,filename,lno,q);
 471   }
 472 }
 473
 474 static const char *instrum_getenv(adns_state ads, const char *envvar) {
 475   const char *value;
 476
 477   value= getenv(envvar);
 478   if (!value) adns__debug(ads,-1,0,"environment variable %s not set",envvar);
 479   else adns__debug(ads,-1,0,"environment variable %s"
 480                    " set to `%s'",envvar,value);
 481   return value;
 482 }
 483
 484 static void readconfig(adns_state ads, const char *filename, int warnmissing) {
 485   getline_ctx gl_ctx;
 486
 487   gl_ctx.file= fopen(filename,"r");
 488   if (!gl_ctx.file) {
 489     if (errno == ENOENT) {
 490       if (warnmissing)
 491         adns__debug(ads,-1,0, "configuration file"
 492                     " `%s' does not exist",filename);
 493       return;
 494     }
 495     saveerr(ads,errno);
 496     adns__diag(ads,-1,0,"cannot open configuration file `%s': %s",
 497                filename,strerror(errno));
 498     return;
 499   }
 500
 501   readconfiggeneric(ads,filename,gl_file,gl_ctx);
 502
 503   fclose(gl_ctx.file);
 504 }
 505
 506 static void readconfigtext(adns_state ads, const char *text,
 507                            const char *showname) {
 508   getline_ctx gl_ctx;
 509
 510   gl_ctx.text= text;
 511   readconfiggeneric(ads,showname,gl_text,gl_ctx);
 512 }
 513
 514 static void readconfigenv(adns_state ads, const char *envvar) {
 515   const char *filename;
 516
 517   if (ads->iflags & adns_if_noenv) {
 518     adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
 519     return;
 520   }
 521   filename= instrum_getenv(ads,envvar);
 522   if (filename) readconfig(ads,filename,1);
 523 }
 524
 525 static void readconfigenvtext(adns_state ads, const char *envvar) {
 526   const char *textdata;
 527
 528   if (ads->iflags & adns_if_noenv) {
 529     adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
 530     return;
 531   }
 532   textdata= instrum_getenv(ads,envvar);
 533   if (textdata) readconfigtext(ads,textdata,envvar);
 534 }
 535
 536
 537 int adns__setnonblock(adns_state ads, int fd) {
 538   int r;
 539
 540   r= fcntl(fd,F_GETFL,0); if (r<0) return errno;
 541   r |= O_NONBLOCK;
 542   r= fcntl(fd,F_SETFL,r); if (r<0) return errno;
 543   return 0;
 544 }
 545
 546 static int init_begin(adns_state *ads_r, adns_initflags flags,
 547                       adns_logcallbackfn *logfn, void *logfndata) {
 548   adns_state ads;
 549   pid_t pid;
 550
 551   ads= malloc(sizeof(*ads)); if (!ads) return errno;
 552
 553   ads->iflags= flags;
 554   ads->logfn= logfn;
 555   ads->logfndata= logfndata;
 556   ads->configerrno= 0;
 557   LIST_INIT(ads->udpw);
 558   LIST_INIT(ads->tcpw);
 559   LIST_INIT(ads->childw);
 560   LIST_INIT(ads->output);
 561   ads->forallnext= 0;
 562   ads->nextid= 0x311f;
 563   ads->nudp= 0;
 564   ads->tcpsocket= -1;
 565   adns__vbuf_init(&ads->tcpsend);
 566   adns__vbuf_init(&ads->tcprecv);
 567   ads->tcprecv_skip= 0;
 568   ads->nservers= ads->nsortlist= ads->nsearchlist= ads->tcpserver= 0;
 569   ads->searchndots= 1;
 570   ads->tcpstate= server_disconnected;
 571   timerclear(&ads->tcptimeout);
 572   ads->searchlist= 0;
 573
 574   pid= getpid();
 575   ads->rand48xsubi[0]= pid;
 576   ads->rand48xsubi[1]= (unsigned long)pid >> 16;
 577   ads->rand48xsubi[2]= pid ^ ((unsigned long)pid >> 16);
 578
 579   *ads_r= ads;
 580   return 0;
 581 }
 582
 583 static int init_finish(adns_state ads) {
 584   struct sockaddr_in sin;
 585   struct protoent *proto;
 586   struct udpsocket *udp;
 587   int i, j;
 588   int r;
 589
 590   if (!ads->nservers) {
 591     if (ads->logfn && ads->iflags & adns_if_debug)
 592       adns__lprintf(ads,"adns: no nameservers, using IPv4 localhost\n");
 593     memset(&sin, 0, sizeof(sin));
 594     sin.sin_family = AF_INET;
 595     sin.sin_port = htons(DNS_PORT);
 596     sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 597     addserver(ads,(struct sockaddr *)&sin, sizeof(sin));
 598   }
 599
 600   proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
 601   ads->nudp= 0;
 602   for (i=0; i<ads->nservers; i++) {
 603     if (adns__udpsocket_by_af(ads, ads->servers[i].addr.sa.sa_family))
 604       continue;
 605     assert(ads->nudp < MAXUDP);
 606     udp= &ads->udpsocket[ads->nudp];
 607     udp->af= ads->servers[i].addr.sa.sa_family;
 608     udp->fd= socket(udp->af,SOCK_DGRAM,proto->p_proto);
 609     if (udp->fd < 0) { r= errno; goto x_free; }
 610     ads->nudp++;
 611     r= adns__setnonblock(ads,udp->fd);
 612     if (r) { r= errno; goto x_closeudp; }
 613   }
 614
 615   return 0;
 616
 617  x_closeudp:
 618   for (j=0; j<ads->nudp; j++) close(ads->udpsocket[j].fd);
 619  x_free:
 620   free(ads);
 621   return r;
 622 }
 623
 624 static void init_abort(adns_state ads) {
 625   if (ads->nsearchlist) {
 626     free(ads->searchlist[0]);
 627     free(ads->searchlist);
 628   }
 629   free(ads);
 630 }
 631
 632 static void logfn_file(adns_state ads, void *logfndata,
 633                        const char *fmt, va_list al) {
 634   vfprintf(logfndata,fmt,al);
 635 }
 636
 637 static int init_files(adns_state *ads_r, adns_initflags flags,
 638                       adns_logcallbackfn *logfn, void *logfndata) {
 639   adns_state ads;
 640   const char *res_options, *adns_res_options;
 641   int r;
 642
 643   r= init_begin(&ads, flags, logfn, logfndata);
 644   if (r) return r;
 645
 646   res_options= instrum_getenv(ads,"RES_OPTIONS");
 647   adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
 648   ccf_options(ads,"RES_OPTIONS",-1,res_options);
 649   ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
 650
 651   readconfig(ads,"/etc/resolv.conf",1);
 652   readconfig(ads,"/etc/resolv-adns.conf",0);
 653   readconfigenv(ads,"RES_CONF");
 654   readconfigenv(ads,"ADNS_RES_CONF");
 655
 656   readconfigenvtext(ads,"RES_CONF_TEXT");
 657   readconfigenvtext(ads,"ADNS_RES_CONF_TEXT");
 658
 659   ccf_options(ads,"RES_OPTIONS",-1,res_options);
 660   ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
 661
 662   ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
 663   ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
 664
 665   if (ads->configerrno && ads->configerrno != EINVAL) {
 666     r= ads->configerrno;
 667     init_abort(ads);
 668     return r;
 669   }
 670
 671   r= init_finish(ads);
 672   if (r) return r;
 673
 674   adns__consistency(ads,0,cc_entex);
 675   *ads_r= ads;
 676   return 0;
 677 }
 678
 679 int adns_init(adns_state *ads_r, adns_initflags flags, FILE *diagfile) {
 680   return init_files(ads_r, flags, logfn_file, diagfile ? diagfile : stderr);
 681 }
 682
 683 static int init_strcfg(adns_state *ads_r, adns_initflags flags,
 684                        adns_logcallbackfn *logfn, void *logfndata,
 685                        const char *configtext) {
 686   adns_state ads;
 687   int r;
 688
 689   r= init_begin(&ads, flags, logfn, logfndata);
 690   if (r) return r;
 691
 692   readconfigtext(ads,configtext,"<supplied configuration text>");
 693   if (ads->configerrno) {
 694     r= ads->configerrno;
 695     init_abort(ads);
 696     return r;
 697   }
 698
 699   r= init_finish(ads);  if (r) return r;
 700   adns__consistency(ads,0,cc_entex);
 701   *ads_r= ads;
 702   return 0;
 703 }
 704
 705 int adns_init_strcfg(adns_state *ads_r, adns_initflags flags,
 706                      FILE *diagfile, const char *configtext) {
 707   return init_strcfg(ads_r, flags,
 708                      diagfile ? logfn_file : 0, diagfile,
 709                      configtext);
 710 }
 711
 712 int adns_init_logfn(adns_state *newstate_r, adns_initflags flags,
 713                     const char *configtext /*0=>use default config files*/,
 714                     adns_logcallbackfn *logfn /*0=>logfndata is a FILE* */,
 715                     void *logfndata /*0 with logfn==0 => discard*/) {
 716   if (!logfn && logfndata)
 717     logfn= logfn_file;
 718   if (configtext)
 719     return init_strcfg(newstate_r, flags, logfn, logfndata, configtext);
 720   else
 721     return init_files(newstate_r, flags, logfn, logfndata);
 722 }
 723
 724 void adns_finish(adns_state ads) {
 725   int i;
 726   adns__consistency(ads,0,cc_entex);
 727   for (;;) {
 728     if (ads->udpw.head) adns__cancel(ads->udpw.head);
 729     else if (ads->tcpw.head) adns__cancel(ads->tcpw.head);
 730     else if (ads->childw.head) adns__cancel(ads->childw.head);
 731     else if (ads->output.head) adns__cancel(ads->output.head);
 732     else break;
 733   }
 734   for (i=0; i<ads->nudp; i++) close(ads->udpsocket[i].fd);
 735   if (ads->tcpsocket >= 0) close(ads->tcpsocket);
 736   adns__vbuf_free(&ads->tcpsend);
 737   adns__vbuf_free(&ads->tcprecv);
 738   freesearchlist(ads);
 739   free(ads);
 740 }
 741
 742 void adns_forallqueries_begin(adns_state ads) {
 743   adns__consistency(ads,0,cc_entex);
 744   ads->forallnext=
 745     ads->udpw.head ? ads->udpw.head :
 746     ads->tcpw.head ? ads->tcpw.head :
 747     ads->childw.head ? ads->childw.head :
 748     ads->output.head;
 749 }
 750
 751 adns_query adns_forallqueries_next(adns_state ads, void **context_r) {
 752   adns_query qu, nqu;
 753
 754   adns__consistency(ads,0,cc_entex);
 755   nqu= ads->forallnext;
 756   for (;;) {
 757     qu= nqu;
 758     if (!qu) return 0;
 759     if (qu->next) {
 760       nqu= qu->next;
 761     } else if (qu == ads->udpw.tail) {
 762       nqu=
 763         ads->tcpw.head ? ads->tcpw.head :
 764         ads->childw.head ? ads->childw.head :
 765         ads->output.head;
 766     } else if (qu == ads->tcpw.tail) {
 767       nqu=
 768         ads->childw.head ? ads->childw.head :
 769         ads->output.head;
 770     } else if (qu == ads->childw.tail) {
 771       nqu= ads->output.head;
 772     } else {
 773       nqu= 0;
 774     }
 775     if (!qu->parent) break;
 776   }
 777   ads->forallnext= nqu;
 778   if (context_r) *context_r= qu->ctx.ext;
 779   return qu;
 780 }