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   const struct sockaddr_in *sin;
  48
  49   assert(sa->sa_family==AF_INET); assert(n>=sizeof(*sin));
  50   sin= (const void *)sa;
  51
  52   for (i=0; i<ads->nservers; i++) {
  53     assert(ads->servers[i].addr.sa.sa_family==AF_INET);
  54     if (ads->servers[i].addr.inet.sin_addr.s_addr == sin->sin_addr.s_addr) {
  55       adns__debug(ads,-1,0,"duplicate nameserver %s ignored",
  56                   inet_ntoa(sin->sin_addr));
  57       return;
  58     }
  59   }
  60
  61   if (ads->nservers>=MAXSERVERS) {
  62     adns__diag(ads,-1,0,"too many nameservers, ignoring %s",
  63                inet_ntoa(sin->sin_addr));
  64     return;
  65   }
  66
  67   ss= ads->servers+ads->nservers;
  68   assert(n <= sizeof(ss->addr));
  69   ss->len = n;
  70   memcpy(&ss->addr, sa, n);
  71   ads->nservers++;
  72 }
  73
  74 static void freesearchlist(adns_state ads) {
  75   if (ads->nsearchlist) free(*ads->searchlist);
  76   free(ads->searchlist);
  77 }
  78
  79 static void saveerr(adns_state ads, int en) {
  80   if (!ads->configerrno) ads->configerrno= en;
  81 }
  82
  83 static void configparseerr(adns_state ads, const char *fn, int lno,
  84                            const char *fmt, ...) {
  85   va_list al;
  86
  87   saveerr(ads,EINVAL);
  88   if (!ads->logfn || (ads->iflags & adns_if_noerrprint)) return;
  89
  90   if (lno==-1) adns__lprintf(ads,"adns: %s: ",fn);
  91   else adns__lprintf(ads,"adns: %s:%d: ",fn,lno);
  92   va_start(al,fmt);
  93   adns__vlprintf(ads,fmt,al);
  94   va_end(al);
  95   adns__lprintf(ads,"\n");
  96 }
  97
  98 static int nextword(const char **bufp_io, const char **word_r, int *l_r) {
  99   const char *p, *q;
 100
 101   p= *bufp_io;
 102   while (ctype_whitespace(*p)) p++;
 103   if (!*p) return 0;
 104
 105   q= p;
 106   while (*q && !ctype_whitespace(*q)) q++;
 107
 108   *l_r= q-p;
 109   *word_r= p;
 110   *bufp_io= q;
 111
 112   return 1;
 113 }
 114
 115 static void ccf_nameserver(adns_state ads, const char *fn,
 116                            int lno, const char *buf) {
 117   struct sockaddr_in sin;
 118
 119   memset(&sin,0,sizeof(sin));
 120   sin.sin_family= AF_INET;
 121   sin.sin_port= htons(DNS_PORT);
 122   if (!inet_aton(buf,&sin.sin_addr)) {
 123     configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf);
 124     return;
 125   }
 126   adns__debug(ads,-1,0,"using nameserver %s",inet_ntoa(sin.sin_addr));
 127   addserver(ads,(const struct sockaddr *)&sin,sizeof(sin));
 128 }
 129
 130 static void ccf_search(adns_state ads, const char *fn,
 131                        int lno, const char *buf) {
 132   const char *bufp, *word;
 133   char *newchars, **newptrs, **pp;
 134   int count, tl, l;
 135
 136   if (!buf) return;
 137
 138   bufp= buf;
 139   count= 0;
 140   tl= 0;
 141   while (nextword(&bufp,&word,&l)) { count++; tl += l+1; }
 142
 143   newptrs= malloc(sizeof(char*)*count);
 144   if (!newptrs) { saveerr(ads,errno); return; }
 145
 146   newchars= malloc(tl);
 147   if (!newchars) { saveerr(ads,errno); free(newptrs); return; }
 148
 149   bufp= buf;
 150   pp= newptrs;
 151   while (nextword(&bufp,&word,&l)) {
 152     *pp++= newchars;
 153     memcpy(newchars,word,l);
 154     newchars += l;
 155     *newchars++ = 0;
 156   }
 157
 158   freesearchlist(ads);
 159   ads->nsearchlist= count;
 160   ads->searchlist= newptrs;
 161 }
 162
 163 static void ccf_sortlist(adns_state ads, const char *fn,
 164                          int lno, const char *buf) {
 165   const char *word;
 166   char tbuf[200], *slash, *ep;
 167   const char *maskwhat;
 168   struct in_addr base, mask;
 169   int l;
 170   unsigned long initial, baselocal;
 171
 172   if (!buf) return;
 173
 174   ads->nsortlist= 0;
 175   while (nextword(&buf,&word,&l)) {
 176     if (ads->nsortlist >= MAXSORTLIST) {
 177       adns__diag(ads,-1,0,"too many sortlist entries,"
 178                  " ignoring %.*s onwards",l,word);
 179       return;
 180     }
 181
 182     if (l >= sizeof(tbuf)) {
 183       configparseerr(ads,fn,lno,"sortlist entry `%.*s' too long",l,word);
 184       continue;
 185     }
 186
 187     memcpy(tbuf,word,l); tbuf[l]= 0;
 188     slash= strchr(tbuf,'/');
 189     if (slash) *slash++= 0;
 190
 191     if (!inet_aton(tbuf,&base)) {
 192       configparseerr(ads,fn,lno,"invalid address `%s' in sortlist",tbuf);
 193       continue;
 194     }
 195
 196     if (slash) {
 197       if (strchr(slash,'.')) {
 198         maskwhat = "mask";
 199         if (!inet_aton(slash,&mask)) {
 200           configparseerr(ads,fn,lno,"invalid mask `%s' in sortlist",slash);
 201           continue;
 202         }
 203       } else {
 204         maskwhat = "prefix length";
 205         initial= strtoul(slash,&ep,10);
 206         if (*ep || initial>32) {
 207           configparseerr(ads,fn,lno,"mask length `%s' invalid",slash);
 208           continue;
 209         }
 210         mask.s_addr= htonl((0x0ffffffffUL) << (32-initial));
 211       }
 212     } else {
 213       maskwhat = "implied mask";
 214       baselocal= ntohl(base.s_addr);
 215       if (!(baselocal & 0x080000000UL)) /* class A */
 216         mask.s_addr= htonl(0x0ff000000UL);
 217       else if ((baselocal & 0x0c0000000UL) == 0x080000000UL)
 218         mask.s_addr= htonl(0x0ffff0000UL); /* class B */
 219       else if ((baselocal & 0x0f0000000UL) == 0x0e0000000UL)
 220         mask.s_addr= htonl(0x0ff000000UL); /* class C */
 221       else {
 222         configparseerr(ads,fn,lno, "network address `%s'"
 223                        " in sortlist is not in classed ranges,"
 224                        " must specify mask explicitly", tbuf);
 225         continue;
 226       }
 227     }
 228
 229     if (base.s_addr & ~mask.s_addr) {
 230       configparseerr(ads,fn,lno, "%s `%s' in sortlist"
 231                      " overlaps address `%s'",maskwhat,
 232                      slash ? slash : inet_ntoa(mask), tbuf);
 233       continue;
 234     }
 235
 236     ads->sortlist[ads->nsortlist].af= AF_INET;
 237     ads->sortlist[ads->nsortlist].base.v4= base;
 238     ads->sortlist[ads->nsortlist].mask.v4= mask;
 239     ads->nsortlist++;
 240   }
 241 }
 242
 243 static void ccf_options(adns_state ads, const char *fn,
 244                         int lno, const char *buf) {
 245   const char *word;
 246   char *ep;
 247   unsigned long v;
 248   int l;
 249
 250   if (!buf) return;
 251
 252   while (nextword(&buf,&word,&l)) {
 253     if (l==5 && !memcmp(word,"debug",5)) {
 254       ads->iflags |= adns_if_debug;
 255       continue;
 256     }
 257     if (l>=6 && !memcmp(word,"ndots:",6)) {
 258       v= strtoul(word+6,&ep,10);
 259       if (l==6 || ep != word+l || v > INT_MAX) {
 260         configparseerr(ads,fn,lno,"option `%.*s' malformed"
 261                        " or has bad value",l,word);
 262         continue;
 263       }
 264       ads->searchndots= v;
 265       continue;
 266     }
 267     if (l>=12 && !memcmp(word,"adns_checkc:",12)) {
 268       if (!strcmp(word+12,"none")) {
 269         ads->iflags &= ~adns_if_checkc_freq;
 270         ads->iflags |= adns_if_checkc_entex;
 271       } else if (!strcmp(word+12,"entex")) {
 272         ads->iflags &= ~adns_if_checkc_freq;
 273         ads->iflags |= adns_if_checkc_entex;
 274       } else if (!strcmp(word+12,"freq")) {
 275         ads->iflags |= adns_if_checkc_freq;
 276       } else {
 277         configparseerr(ads,fn,lno, "option adns_checkc has bad value `%s' "
 278                        "(must be none, entex or freq", word+12);
 279       }
 280       continue;
 281     }
 282     adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,word);
 283   }
 284 }
 285
 286 static void ccf_clearnss(adns_state ads, const char *fn,
 287                          int lno, const char *buf) {
 288   ads->nservers= 0;
 289 }
 290
 291 static void ccf_include(adns_state ads, const char *fn,
 292                         int lno, const char *buf) {
 293   if (!*buf) {
 294     configparseerr(ads,fn,lno,"`include' directive with no filename");
 295     return;
 296   }
 297   readconfig(ads,buf,1);
 298 }
 299
 300 static void ccf_lookup(adns_state ads, const char *fn, int lno,
 301                        const char *buf) {
 302   int found_bind=0;
 303   const char *word;
 304   int l;
 305
 306   if (!*buf) {
 307     configparseerr(ads,fn,lno,"`lookup' directive with no databases");
 308     return;
 309   }
 310
 311   while (nextword(&buf,&word,&l)) {
 312     if (l==4 && !memcmp(word,"bind",4)) {
 313       found_bind=1;
 314     } else if (l==4 && !memcmp(word,"file",4)) {
 315       /* ignore this and hope /etc/hosts is not essential */
 316     } else if (l==2 && !memcmp(word,"yp",2)) {
 317       adns__diag(ads,-1,0,"%s:%d: yp lookups not supported by adns", fn,lno);
 318       found_bind=-1;
 319     } else {
 320       adns__diag(ads,-1,0,"%s:%d: unknown `lookup' database `%.*s'",
 321                  fn,lno, l,word);
 322       found_bind=-1;
 323     }
 324   }
 325   if (!found_bind)
 326     adns__diag(ads,-1,0,"%s:%d: `lookup' specified, but not `bind'", fn,lno);
 327 }
 328
 329 static const struct configcommandinfo {
 330   const char *name;
 331   void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
 332 } configcommandinfos[]= {
 333   { "nameserver",        ccf_nameserver  },
 334   { "domain",            ccf_search      },
 335   { "search",            ccf_search      },
 336   { "sortlist",          ccf_sortlist    },
 337   { "options",           ccf_options     },
 338   { "clearnameservers",  ccf_clearnss    },
 339   { "include",           ccf_include     },
 340   { "lookup",            ccf_lookup      }, /* OpenBSD */
 341   {  0                                   }
 342 };
 343
 344 typedef union {
 345   FILE *file;
 346   const char *text;
 347 } getline_ctx;
 348
 349 static int gl_file(adns_state ads, getline_ctx *src_io, const char *filename,
 350                    int lno, char *buf, int buflen) {
 351   FILE *file= src_io->file;
 352   int c, i;
 353   char *p;
 354
 355   p= buf;
 356   buflen--;
 357   i= 0;
 358
 359   for (;;) { /* loop over chars */
 360     if (i == buflen) {
 361       adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
 362       goto x_badline;
 363     }
 364     c= getc(file);
 365     if (!c) {
 366       adns__diag(ads,-1,0,"%s:%d: line contains nul, ignored",filename,lno);
 367       goto x_badline;
 368     } else if (c == '\n') {
 369       break;
 370     } else if (c == EOF) {
 371       if (ferror(file)) {
 372         saveerr(ads,errno);
 373         adns__diag(ads,-1,0,"%s:%d: read error: %s",
 374                    filename,lno,strerror(errno));
 375         return -1;
 376       }
 377       if (!i) return -1;
 378       break;
 379     } else {
 380       *p++= c;
 381       i++;
 382     }
 383   }
 384
 385   *p++= 0;
 386   return i;
 387
 388  x_badline:
 389   saveerr(ads,EINVAL);
 390   while ((c= getc(file)) != EOF && c != '\n');
 391   return -2;
 392 }
 393
 394 static int gl_text(adns_state ads, getline_ctx *src_io, const char *filename,
 395                    int lno, char *buf, int buflen) {
 396   const char *cp= src_io->text;
 397   int l;
 398
 399   if (!cp || !*cp) return -1;
 400
 401   if (*cp == ';' || *cp == '\n') cp++;
 402   l= strcspn(cp,";\n");
 403   src_io->text = cp+l;
 404
 405   if (l >= buflen) {
 406     adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
 407     saveerr(ads,EINVAL);
 408     return -2;
 409   }
 410
 411   memcpy(buf,cp,l);
 412   buf[l]= 0;
 413   return l;
 414 }
 415
 416 static void readconfiggeneric(adns_state ads, const char *filename,
 417                               int (*getline)(adns_state ads, getline_ctx*,
 418                                              const char *filename, int lno,
 419                                              char *buf, int buflen),
 420                               /* Returns >=0 for success, -1 for EOF or error
 421                                * (error will have been reported), or -2 for
 422                                * bad line was encountered, try again.
 423                                */
 424                               getline_ctx gl_ctx) {
 425   char linebuf[2000], *p, *q;
 426   int lno, l, dirl;
 427   const struct configcommandinfo *ccip;
 428
 429   for (lno=1;
 430        (l= getline(ads,&gl_ctx, filename,lno, linebuf,sizeof(linebuf))) != -1;
 431        lno++) {
 432     if (l == -2) continue;
 433     while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
 434     linebuf[l]= 0;
 435     p= linebuf;
 436     while (ctype_whitespace(*p)) p++;
 437     if (*p == '#' || *p == ';' || !*p) continue;
 438     q= p;
 439     while (*q && !ctype_whitespace(*q)) q++;
 440     dirl= q-p;
 441     for (ccip=configcommandinfos;
 442          ccip->name &&
 443            !(strlen(ccip->name)==dirl && !memcmp(ccip->name,p,q-p));
 444          ccip++);
 445     if (!ccip->name) {
 446       adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'",
 447                  filename,lno,(int)(q-p),p);
 448       continue;
 449     }
 450     while (ctype_whitespace(*q)) q++;
 451     ccip->fn(ads,filename,lno,q);
 452   }
 453 }
 454
 455 static const char *instrum_getenv(adns_state ads, const char *envvar) {
 456   const char *value;
 457
 458   value= getenv(envvar);
 459   if (!value) adns__debug(ads,-1,0,"environment variable %s not set",envvar);
 460   else adns__debug(ads,-1,0,"environment variable %s"
 461                    " set to `%s'",envvar,value);
 462   return value;
 463 }
 464
 465 static void readconfig(adns_state ads, const char *filename, int warnmissing) {
 466   getline_ctx gl_ctx;
 467
 468   gl_ctx.file= fopen(filename,"r");
 469   if (!gl_ctx.file) {
 470     if (errno == ENOENT) {
 471       if (warnmissing)
 472         adns__debug(ads,-1,0, "configuration file"
 473                     " `%s' does not exist",filename);
 474       return;
 475     }
 476     saveerr(ads,errno);
 477     adns__diag(ads,-1,0,"cannot open configuration file `%s': %s",
 478                filename,strerror(errno));
 479     return;
 480   }
 481
 482   readconfiggeneric(ads,filename,gl_file,gl_ctx);
 483
 484   fclose(gl_ctx.file);
 485 }
 486
 487 static void readconfigtext(adns_state ads, const char *text,
 488                            const char *showname) {
 489   getline_ctx gl_ctx;
 490
 491   gl_ctx.text= text;
 492   readconfiggeneric(ads,showname,gl_text,gl_ctx);
 493 }
 494
 495 static void readconfigenv(adns_state ads, const char *envvar) {
 496   const char *filename;
 497
 498   if (ads->iflags & adns_if_noenv) {
 499     adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
 500     return;
 501   }
 502   filename= instrum_getenv(ads,envvar);
 503   if (filename) readconfig(ads,filename,1);
 504 }
 505
 506 static void readconfigenvtext(adns_state ads, const char *envvar) {
 507   const char *textdata;
 508
 509   if (ads->iflags & adns_if_noenv) {
 510     adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
 511     return;
 512   }
 513   textdata= instrum_getenv(ads,envvar);
 514   if (textdata) readconfigtext(ads,textdata,envvar);
 515 }
 516
 517
 518 int adns__setnonblock(adns_state ads, int fd) {
 519   int r;
 520
 521   r= fcntl(fd,F_GETFL,0); if (r<0) return errno;
 522   r |= O_NONBLOCK;
 523   r= fcntl(fd,F_SETFL,r); if (r<0) return errno;
 524   return 0;
 525 }
 526
 527 static int init_begin(adns_state *ads_r, adns_initflags flags,
 528                       adns_logcallbackfn *logfn, void *logfndata) {
 529   adns_state ads;
 530   pid_t pid;
 531
 532   ads= malloc(sizeof(*ads)); if (!ads) return errno;
 533
 534   ads->iflags= flags;
 535   ads->logfn= logfn;
 536   ads->logfndata= logfndata;
 537   ads->configerrno= 0;
 538   LIST_INIT(ads->udpw);
 539   LIST_INIT(ads->tcpw);
 540   LIST_INIT(ads->childw);
 541   LIST_INIT(ads->output);
 542   ads->forallnext= 0;
 543   ads->nextid= 0x311f;
 544   ads->udpsocket= ads->tcpsocket= -1;
 545   adns__vbuf_init(&ads->tcpsend);
 546   adns__vbuf_init(&ads->tcprecv);
 547   ads->tcprecv_skip= 0;
 548   ads->nservers= ads->nsortlist= ads->nsearchlist= ads->tcpserver= 0;
 549   ads->searchndots= 1;
 550   ads->tcpstate= server_disconnected;
 551   timerclear(&ads->tcptimeout);
 552   ads->searchlist= 0;
 553
 554   pid= getpid();
 555   ads->rand48xsubi[0]= pid;
 556   ads->rand48xsubi[1]= (unsigned long)pid >> 16;
 557   ads->rand48xsubi[2]= pid ^ ((unsigned long)pid >> 16);
 558
 559   *ads_r= ads;
 560   return 0;
 561 }
 562
 563 static int init_finish(adns_state ads) {
 564   struct sockaddr_in sin;
 565   struct protoent *proto;
 566   int i, r;
 567
 568   if (!ads->nservers) {
 569     if (ads->logfn && ads->iflags & adns_if_debug)
 570       adns__lprintf(ads,"adns: no nameservers, using IPv4 localhost\n");
 571     memset(&sin, 0, sizeof(sin));
 572     sin.sin_family = AF_INET;
 573     sin.sin_port = htons(DNS_PORT);
 574     sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 575     addserver(ads,(struct sockaddr *)&sin, sizeof(sin));
 576   }
 577
 578   /* we can't cope with multiple transport address families yet */
 579   for (i=0; i<ads->nservers; i++)
 580     assert(ads->servers[i].addr.sa.sa_family==AF_INET);
 581
 582   proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
 583   ads->udpsocket= socket(AF_INET,SOCK_DGRAM,proto->p_proto);
 584   if (ads->udpsocket<0) { r= errno; goto x_free; }
 585
 586   r= adns__setnonblock(ads,ads->udpsocket);
 587   if (r) { r= errno; goto x_closeudp; }
 588
 589   return 0;
 590
 591  x_closeudp:
 592   close(ads->udpsocket);
 593  x_free:
 594   free(ads);
 595   return r;
 596 }
 597
 598 static void init_abort(adns_state ads) {
 599   if (ads->nsearchlist) {
 600     free(ads->searchlist[0]);
 601     free(ads->searchlist);
 602   }
 603   free(ads);
 604 }
 605
 606 static void logfn_file(adns_state ads, void *logfndata,
 607                        const char *fmt, va_list al) {
 608   vfprintf(logfndata,fmt,al);
 609 }
 610
 611 static int init_files(adns_state *ads_r, adns_initflags flags,
 612                       adns_logcallbackfn *logfn, void *logfndata) {
 613   adns_state ads;
 614   const char *res_options, *adns_res_options;
 615   int r;
 616
 617   r= init_begin(&ads, flags, logfn, logfndata);
 618   if (r) return r;
 619
 620   res_options= instrum_getenv(ads,"RES_OPTIONS");
 621   adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
 622   ccf_options(ads,"RES_OPTIONS",-1,res_options);
 623   ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
 624
 625   readconfig(ads,"/etc/resolv.conf",1);
 626   readconfig(ads,"/etc/resolv-adns.conf",0);
 627   readconfigenv(ads,"RES_CONF");
 628   readconfigenv(ads,"ADNS_RES_CONF");
 629
 630   readconfigenvtext(ads,"RES_CONF_TEXT");
 631   readconfigenvtext(ads,"ADNS_RES_CONF_TEXT");
 632
 633   ccf_options(ads,"RES_OPTIONS",-1,res_options);
 634   ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
 635
 636   ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
 637   ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
 638
 639   if (ads->configerrno && ads->configerrno != EINVAL) {
 640     r= ads->configerrno;
 641     init_abort(ads);
 642     return r;
 643   }
 644
 645   r= init_finish(ads);
 646   if (r) return r;
 647
 648   adns__consistency(ads,0,cc_entex);
 649   *ads_r= ads;
 650   return 0;
 651 }
 652
 653 int adns_init(adns_state *ads_r, adns_initflags flags, FILE *diagfile) {
 654   return init_files(ads_r, flags, logfn_file, diagfile ? diagfile : stderr);
 655 }
 656
 657 static int init_strcfg(adns_state *ads_r, adns_initflags flags,
 658                        adns_logcallbackfn *logfn, void *logfndata,
 659                        const char *configtext) {
 660   adns_state ads;
 661   int r;
 662
 663   r= init_begin(&ads, flags, logfn, logfndata);
 664   if (r) return r;
 665
 666   readconfigtext(ads,configtext,"<supplied configuration text>");
 667   if (ads->configerrno) {
 668     r= ads->configerrno;
 669     init_abort(ads);
 670     return r;
 671   }
 672
 673   r= init_finish(ads);  if (r) return r;
 674   adns__consistency(ads,0,cc_entex);
 675   *ads_r= ads;
 676   return 0;
 677 }
 678
 679 int adns_init_strcfg(adns_state *ads_r, adns_initflags flags,
 680                      FILE *diagfile, const char *configtext) {
 681   return init_strcfg(ads_r, flags,
 682                      diagfile ? logfn_file : 0, diagfile,
 683                      configtext);
 684 }
 685
 686 int adns_init_logfn(adns_state *newstate_r, adns_initflags flags,
 687                     const char *configtext /*0=>use default config files*/,
 688                     adns_logcallbackfn *logfn /*0=>logfndata is a FILE* */,
 689                     void *logfndata /*0 with logfn==0 => discard*/) {
 690   if (!logfn && logfndata)
 691     logfn= logfn_file;
 692   if (configtext)
 693     return init_strcfg(newstate_r, flags, logfn, logfndata, configtext);
 694   else
 695     return init_files(newstate_r, flags, logfn, logfndata);
 696 }
 697
 698 void adns_finish(adns_state ads) {
 699   adns__consistency(ads,0,cc_entex);
 700   for (;;) {
 701     if (ads->udpw.head) adns_cancel(ads->udpw.head);
 702     else if (ads->tcpw.head) adns_cancel(ads->tcpw.head);
 703     else if (ads->childw.head) adns_cancel(ads->childw.head);
 704     else if (ads->output.head) adns_cancel(ads->output.head);
 705     else break;
 706   }
 707   close(ads->udpsocket);
 708   if (ads->tcpsocket >= 0) close(ads->tcpsocket);
 709   adns__vbuf_free(&ads->tcpsend);
 710   adns__vbuf_free(&ads->tcprecv);
 711   freesearchlist(ads);
 712   free(ads);
 713 }
 714
 715 void adns_forallqueries_begin(adns_state ads) {
 716   adns__consistency(ads,0,cc_entex);
 717   ads->forallnext=
 718     ads->udpw.head ? ads->udpw.head :
 719     ads->tcpw.head ? ads->tcpw.head :
 720     ads->childw.head ? ads->childw.head :
 721     ads->output.head;
 722 }
 723
 724 adns_query adns_forallqueries_next(adns_state ads, void **context_r) {
 725   adns_query qu, nqu;
 726
 727   adns__consistency(ads,0,cc_entex);
 728   nqu= ads->forallnext;
 729   for (;;) {
 730     qu= nqu;
 731     if (!qu) return 0;
 732     if (qu->next) {
 733       nqu= qu->next;
 734     } else if (qu == ads->udpw.tail) {
 735       nqu=
 736         ads->tcpw.head ? ads->tcpw.head :
 737         ads->childw.head ? ads->childw.head :
 738         ads->output.head;
 739     } else if (qu == ads->tcpw.tail) {
 740       nqu=
 741         ads->childw.head ? ads->childw.head :
 742         ads->output.head;
 743     } else if (qu == ads->childw.tail) {
 744       nqu= ads->output.head;
 745     } else {
 746       nqu= 0;
 747     }
 748     if (!qu->parent) break;
 749   }
 750   ads->forallnext= nqu;
 751   if (context_r) *context_r= qu->ctx.ext;
 752   return qu;
 753 }