apt-pkg/contrib/configuration.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: configuration.cc,v 1.28 2004/04/30 04:00:15 mdz Exp $
   4 /* ######################################################################
   5
   6    Configuration Class
   7
   8    This class provides a configuration file and command line parser
   9    for a tree-oriented configuration environment. All runtime configuration
  10    is stored in here.
  11
  12    This source is placed in the Public Domain, do with it what you will
  13    It was originally written by Jason Gunthorpe <jgg@debian.org>.
  14
  15    ##################################################################### */
  16                                                                         /*}}}*/
  17 // Include files                                                        /*{{{*/
  18 #ifdef __GNUG__
  19 #pragma implementation "apt-pkg/configuration.h"
  20 #endif
  21 #include <apt-pkg/configuration.h>
  22 #include <apt-pkg/error.h>
  23 #include <apt-pkg/strutl.h>
  24 #include <apt-pkg/fileutl.h>
  25 #include <apti18n.h>
  26
  27 #include <vector>
  28 #include <algorithm>
  29 #include <fstream>
  30 #include <iostream>
  31
  32 #include <stdio.h>
  33 #include <dirent.h>
  34 #include <sys/stat.h>
  35 #include <unistd.h>
  36
  37 using namespace std;
  38                                                                         /*}}}*/
  39
  40 Configuration *_config = new Configuration;
  41
  42 // Configuration::Configuration - Constructor                           /*{{{*/
  43 // ---------------------------------------------------------------------
  44 /* */
  45 Configuration::Configuration() : ToFree(true)
  46 {
  47    Root = new Item;
  48 }
  49 Configuration::Configuration(const Item *Root) : Root((Item *)Root), ToFree(false)
  50 {
  51 };
  52
  53                                                                         /*}}}*/
  54 // Configuration::~Configuration - Destructor                           /*{{{*/
  55 // ---------------------------------------------------------------------
  56 /* */
  57 Configuration::~Configuration()
  58 {
  59    if (ToFree == false)
  60       return;
  61
  62    Item *Top = Root;
  63    for (; Top != 0;)
  64    {
  65       if (Top->Child != 0)
  66       {
  67          Top = Top->Child;
  68          continue;
  69       }
  70
  71       while (Top != 0 && Top->Next == 0)
  72       {
  73          Item *Parent = Top->Parent;
  74          delete Top;
  75          Top = Parent;
  76       }
  77       if (Top != 0)
  78       {
  79          Item *Next = Top->Next;
  80          delete Top;
  81          Top = Next;
  82       }
  83    }
  84 }
  85                                                                         /*}}}*/
  86 // Configuration::Lookup - Lookup a single item                         /*{{{*/
  87 // ---------------------------------------------------------------------
  88 /* This will lookup a single item by name below another item. It is a
  89    helper function for the main lookup function */
  90 Configuration::Item *Configuration::Lookup(Item *Head,const char *S,
  91                                            unsigned long Len,bool Create)
  92 {
  93    int Res = 1;
  94    Item *I = Head->Child;
  95    Item **Last = &Head->Child;
  96
  97    // Empty strings match nothing. They are used for lists.
  98    if (Len != 0)
  99    {
 100       for (; I != 0; Last = &I->Next, I = I->Next)
 101          if ((Res = stringcasecmp(I->Tag,S,S + Len)) == 0)
 102             break;
 103    }
 104    else
 105       for (; I != 0; Last = &I->Next, I = I->Next);
 106
 107    if (Res == 0)
 108       return I;
 109    if (Create == false)
 110       return 0;
 111
 112    I = new Item;
 113    I->Tag = string(S,Len);
 114    I->Next = *Last;
 115    I->Parent = Head;
 116    *Last = I;
 117    return I;
 118 }
 119                                                                         /*}}}*/
 120 // Configuration::Lookup - Lookup a fully scoped item                   /*{{{*/
 121 // ---------------------------------------------------------------------
 122 /* This performs a fully scoped lookup of a given name, possibly creating
 123    new items */
 124 Configuration::Item *Configuration::Lookup(const char *Name,bool Create)
 125 {
 126    if (Name == 0)
 127       return Root->Child;
 128
 129    const char *Start = Name;
 130    const char *End = Start + strlen(Name);
 131    const char *TagEnd = Name;
 132    Item *Itm = Root;
 133    for (; End - TagEnd >= 2; TagEnd++)
 134    {
 135       if (TagEnd[0] == ':' && TagEnd[1] == ':')
 136       {
 137          Itm = Lookup(Itm,Start,TagEnd - Start,Create);
 138          if (Itm == 0)
 139             return 0;
 140          TagEnd = Start = TagEnd + 2;
 141       }
 142    }
 143
 144    // This must be a trailing ::, we create unique items in a list
 145    if (End - Start == 0)
 146    {
 147       if (Create == false)
 148          return 0;
 149    }
 150
 151    Itm = Lookup(Itm,Start,End - Start,Create);
 152    return Itm;
 153 }
 154                                                                         /*}}}*/
 155 // Configuration::Find - Find a value                                   /*{{{*/
 156 // ---------------------------------------------------------------------
 157 /* */
 158 string Configuration::Find(const char *Name,const char *Default) const
 159 {
 160    const Item *Itm = Lookup(Name);
 161    if (Itm == 0 || Itm->Value.empty() == true)
 162    {
 163       if (Default == 0)
 164          return string();
 165       else
 166          return Default;
 167    }
 168
 169    return Itm->Value;
 170 }
 171                                                                         /*}}}*/
 172 // Configuration::FindFile - Find a Filename                            /*{{{*/
 173 // ---------------------------------------------------------------------
 174 /* Directories are stored as the base dir in the Parent node and the
 175    sub directory in sub nodes with the final node being the end filename
 176  */
 177 string Configuration::FindFile(const char *Name,const char *Default) const
 178 {
 179    const Item *Itm = Lookup(Name);
 180    if (Itm == 0 || Itm->Value.empty() == true)
 181    {
 182       if (Default == 0)
 183          return string();
 184       else
 185          return Default;
 186    }
 187
 188    string val = Itm->Value;
 189    while (Itm->Parent != 0 && Itm->Parent->Value.empty() == false)
 190    {
 191       // Absolute
 192       if (val.length() >= 1 && val[0] == '/')
 193          break;
 194
 195       // ~/foo or ./foo
 196       if (val.length() >= 2 && (val[0] == '~' || val[0] == '.') && val[1] == '/')
 197          break;
 198
 199       // ../foo
 200       if (val.length() >= 3 && val[0] == '.' && val[1] == '.' && val[2] == '/')
 201          break;
 202
 203       if (Itm->Parent->Value.end()[-1] != '/')
 204          val.insert(0, "/");
 205
 206       val.insert(0, Itm->Parent->Value);
 207       Itm = Itm->Parent;
 208    }
 209
 210    return val;
 211 }
 212                                                                         /*}}}*/
 213 // Configuration::FindDir - Find a directory name                       /*{{{*/
 214 // ---------------------------------------------------------------------
 215 /* This is like findfile execept the result is terminated in a / */
 216 string Configuration::FindDir(const char *Name,const char *Default) const
 217 {
 218    string Res = FindFile(Name,Default);
 219    if (Res.end()[-1] != '/')
 220       return Res + '/';
 221    return Res;
 222 }
 223                                                                         /*}}}*/
 224 // Configuration::FindI - Find an integer value                         /*{{{*/
 225 // ---------------------------------------------------------------------
 226 /* */
 227 int Configuration::FindI(const char *Name,int Default) const
 228 {
 229    const Item *Itm = Lookup(Name);
 230    if (Itm == 0 || Itm->Value.empty() == true)
 231       return Default;
 232
 233    char *End;
 234    int Res = strtol(Itm->Value.c_str(),&End,0);
 235    if (End == Itm->Value.c_str())
 236       return Default;
 237
 238    return Res;
 239 }
 240                                                                         /*}}}*/
 241 // Configuration::FindB - Find a boolean type                           /*{{{*/
 242 // ---------------------------------------------------------------------
 243 /* */
 244 bool Configuration::FindB(const char *Name,bool Default) const
 245 {
 246    const Item *Itm = Lookup(Name);
 247    if (Itm == 0 || Itm->Value.empty() == true)
 248       return Default;
 249
 250    return StringToBool(Itm->Value,Default);
 251 }
 252                                                                         /*}}}*/
 253 // Configuration::FindAny - Find an arbitrary type                      /*{{{*/
 254 // ---------------------------------------------------------------------
 255 /* a key suffix of /f, /d, /b or /i calls Find{File,Dir,B,I} */
 256 string Configuration::FindAny(const char *Name,const char *Default) const
 257 {
 258    string key = Name;
 259    char type = 0;
 260
 261    if (key.size() > 2 && key.end()[-2] == '/')
 262    {
 263       type = key.end()[-1];
 264       key.resize(key.size() - 2);
 265    }
 266
 267    switch (type)
 268    {
 269       // file
 270       case 'f':
 271       return FindFile(key.c_str(), Default);
 272
 273       // directory
 274       case 'd':
 275       return FindDir(key.c_str(), Default);
 276
 277       // bool
 278       case 'b':
 279       return FindB(key, Default) ? "true" : "false";
 280
 281       // int
 282       case 'i':
 283       {
 284          char buf[16];
 285          snprintf(buf, sizeof(buf)-1, "%d", FindI(key, Default ? atoi(Default) : 0 ));
 286          return buf;
 287       }
 288    }
 289
 290    // fallback
 291    return Find(Name, Default);
 292 }
 293                                                                         /*}}}*/
 294 // Configuration::CndSet - Conditinal Set a value                       /*{{{*/
 295 // ---------------------------------------------------------------------
 296 /* This will not overwrite */
 297 void Configuration::CndSet(const char *Name,string Value)
 298 {
 299    Item *Itm = Lookup(Name,true);
 300    if (Itm == 0)
 301       return;
 302    if (Itm->Value.empty() == true)
 303       Itm->Value = Value;
 304 }
 305                                                                         /*}}}*/
 306 // Configuration::Set - Set a value                                     /*{{{*/
 307 // ---------------------------------------------------------------------
 308 /* */
 309 void Configuration::Set(const char *Name,string Value)
 310 {
 311    Item *Itm = Lookup(Name,true);
 312    if (Itm == 0)
 313       return;
 314    Itm->Value = Value;
 315 }
 316                                                                         /*}}}*/
 317 // Configuration::Set - Set an integer value                            /*{{{*/
 318 // ---------------------------------------------------------------------
 319 /* */
 320 void Configuration::Set(const char *Name,int Value)
 321 {
 322    Item *Itm = Lookup(Name,true);
 323    if (Itm == 0)
 324       return;
 325    char S[300];
 326    snprintf(S,sizeof(S),"%i",Value);
 327    Itm->Value = S;
 328 }
 329                                                                         /*}}}*/
 330 // Configuration::Clear - Clear an entire tree                          /*{{{*/
 331 // ---------------------------------------------------------------------
 332 /* */
 333 void Configuration::Clear(string Name)
 334 {
 335    Item *Top = Lookup(Name.c_str(),false);
 336    if (Top == 0)
 337       return;
 338
 339    Top->Value = string();
 340    Item *Stop = Top;
 341    Top = Top->Child;
 342    Stop->Child = 0;
 343    for (; Top != 0;)
 344    {
 345       if (Top->Child != 0)
 346       {
 347          Top = Top->Child;
 348          continue;
 349       }
 350
 351       while (Top != 0 && Top->Next == 0)
 352       {
 353          Item *Tmp = Top;
 354          Top = Top->Parent;
 355          delete Tmp;
 356
 357          if (Top == Stop)
 358             return;
 359       }
 360
 361       Item *Tmp = Top;
 362       if (Top != 0)
 363          Top = Top->Next;
 364       delete Tmp;
 365    }
 366 }
 367                                                                         /*}}}*/
 368 // Configuration::Exists - Returns true if the Name exists              /*{{{*/
 369 // ---------------------------------------------------------------------
 370 /* */
 371 bool Configuration::Exists(const char *Name) const
 372 {
 373    const Item *Itm = Lookup(Name);
 374    if (Itm == 0)
 375       return false;
 376    return true;
 377 }
 378                                                                         /*}}}*/
 379 // Configuration::ExistsAny - Returns true if the Name, possibly        /*{{{*/
 380 // ---------------------------------------------------------------------
 381 /* qualified by /[fdbi] exists */
 382 bool Configuration::ExistsAny(const char *Name) const
 383 {
 384    string key = Name;
 385
 386    if (key.size() > 2 && key.end()[-2] == '/')
 387       if (key.find_first_of("fdbi",key.size()-1) < key.size())
 388       {
 389          key.resize(key.size() - 2);
 390          if (Exists(key.c_str()))
 391             return true;
 392       }
 393       else
 394       {
 395          _error->Warning(_("Unrecognized type abbreviation: '%c'"), key.end()[-3]);
 396       }
 397
 398    return Exists(Name);
 399 }
 400                                                                         /*}}}*/
 401 // Configuration::Dump - Dump the config                                /*{{{*/
 402 // ---------------------------------------------------------------------
 403 /* Dump the entire configuration space */
 404 void Configuration::Dump(ostream& str)
 405 {
 406    /* Write out all of the configuration directives by walking the
 407       configuration tree */
 408    const Configuration::Item *Top = Tree(0);
 409    for (; Top != 0;)
 410    {
 411       str << Top->FullTag() << " \"" << Top->Value << "\";" << endl;
 412
 413       if (Top->Child != 0)
 414       {
 415          Top = Top->Child;
 416          continue;
 417       }
 418
 419       while (Top != 0 && Top->Next == 0)
 420          Top = Top->Parent;
 421       if (Top != 0)
 422          Top = Top->Next;
 423    }
 424 }
 425                                                                         /*}}}*/
 426
 427 // Configuration::Item::FullTag - Return the fully scoped tag           /*{{{*/
 428 // ---------------------------------------------------------------------
 429 /* Stop sets an optional max recursion depth if this item is being viewed as
 430    part of a sub tree. */
 431 string Configuration::Item::FullTag(const Item *Stop) const
 432 {
 433    if (Parent == 0 || Parent->Parent == 0 || Parent == Stop)
 434       return Tag;
 435    return Parent->FullTag(Stop) + "::" + Tag;
 436 }
 437                                                                         /*}}}*/
 438
 439 // ReadConfigFile - Read a configuration file                           /*{{{*/
 440 // ---------------------------------------------------------------------
 441 /* The configuration format is very much like the named.conf format
 442    used in bind8, in fact this routine can parse most named.conf files.
 443    Sectional config files are like bind's named.conf where there are
 444    sections like 'zone "foo.org" { .. };' This causes each section to be
 445    added in with a tag like "zone::foo.org" instead of being split
 446    tag/value. AsSectional enables Sectional parsing.*/
 447 bool ReadConfigFile(Configuration &Conf,string FName,bool AsSectional,
 448                     unsigned Depth)
 449 {
 450    // Open the stream for reading
 451    ifstream F(FName.c_str(),ios::in);
 452    if (!F != 0)
 453       return _error->Errno("ifstream::ifstream",_("Opening configuration file %s"),FName.c_str());
 454
 455    char Buffer[1024];
 456    string LineBuffer;
 457    string Stack[100];
 458    unsigned int StackPos = 0;
 459
 460    // Parser state
 461    string ParentTag;
 462
 463    int CurLine = 0;
 464    bool InComment = false;
 465    while (F.eof() == false)
 466    {
 467       F.getline(Buffer,sizeof(Buffer));
 468       CurLine++;
 469       // This should be made to work instead, but this is better than looping
 470       if (F.fail() && !F.eof())
 471          return _error->Error(_("Line %d too long (max %d)"), CurLine, sizeof(Buffer));
 472
 473       _strtabexpand(Buffer,sizeof(Buffer));
 474       _strstrip(Buffer);
 475
 476       // Multi line comment
 477       if (InComment == true)
 478       {
 479          for (const char *I = Buffer; *I != 0; I++)
 480          {
 481             if (*I == '*' && I[1] == '/')
 482             {
 483                memmove(Buffer,I+2,strlen(I+2) + 1);
 484                InComment = false;
 485                break;
 486             }
 487          }
 488          if (InComment == true)
 489             continue;
 490       }
 491
 492       // Discard single line comments
 493       bool InQuote = false;
 494       for (char *I = Buffer; *I != 0; I++)
 495       {
 496          if (*I == '"')
 497             InQuote = !InQuote;
 498          if (InQuote == true)
 499             continue;
 500
 501          if (*I == '/' && I[1] == '/')
 502          {
 503             *I = 0;
 504             break;
 505          }
 506       }
 507
 508       // Look for multi line comments
 509       InQuote = false;
 510       for (char *I = Buffer; *I != 0; I++)
 511       {
 512          if (*I == '"')
 513             InQuote = !InQuote;
 514          if (InQuote == true)
 515             continue;
 516
 517          if (*I == '/' && I[1] == '*')
 518          {
 519             InComment = true;
 520             for (char *J = Buffer; *J != 0; J++)
 521             {
 522                if (*J == '*' && J[1] == '/')
 523                {
 524                   memmove(I,J+2,strlen(J+2) + 1);
 525                   InComment = false;
 526                   break;
 527                }
 528             }
 529
 530             if (InComment == true)
 531             {
 532                *I = 0;
 533                break;
 534             }
 535          }
 536       }
 537
 538       // Blank
 539       if (Buffer[0] == 0)
 540          continue;
 541
 542       // We now have a valid line fragment
 543       InQuote = false;
 544       for (char *I = Buffer; *I != 0;)
 545       {
 546          if (*I == '"')
 547             InQuote = !InQuote;
 548
 549          if (InQuote == false && (*I == '{' || *I == ';' || *I == '}'))
 550          {
 551             // Put the last fragment into the buffer
 552             char *Start = Buffer;
 553             char *Stop = I;
 554             for (; Start != I && isspace(*Start) != 0; Start++);
 555             for (; Stop != Start && isspace(Stop[-1]) != 0; Stop--);
 556             if (LineBuffer.empty() == false && Stop - Start != 0)
 557                LineBuffer += ' ';
 558             LineBuffer += string(Start,Stop - Start);
 559
 560             // Remove the fragment
 561             char TermChar = *I;
 562             memmove(Buffer,I + 1,strlen(I + 1) + 1);
 563             I = Buffer;
 564
 565             // Syntax Error
 566             if (TermChar == '{' && LineBuffer.empty() == true)
 567                return _error->Error(_("Syntax error %s:%u: Block starts with no name."),FName.c_str(),CurLine);
 568
 569             // No string on this line
 570             if (LineBuffer.empty() == true)
 571             {
 572                if (TermChar == '}')
 573                {
 574                   if (StackPos == 0)
 575                      ParentTag = string();
 576                   else
 577                      ParentTag = Stack[--StackPos];
 578                }
 579                continue;
 580             }
 581
 582             // Parse off the tag
 583             string Tag;
 584             const char *Pos = LineBuffer.c_str();
 585             if (ParseQuoteWord(Pos,Tag) == false)
 586                return _error->Error(_("Syntax error %s:%u: Malformed tag"),FName.c_str(),CurLine);
 587
 588             // Parse off the word
 589             string Word;
 590             bool NoWord = false;
 591             if (ParseCWord(Pos,Word) == false &&
 592                 ParseQuoteWord(Pos,Word) == false)
 593             {
 594                if (TermChar != '{')
 595                {
 596                   Word = Tag;
 597                   Tag = "";
 598                }
 599                else
 600                   NoWord = true;
 601             }
 602             if (strlen(Pos) != 0)
 603                return _error->Error(_("Syntax error %s:%u: Extra junk after value"),FName.c_str(),CurLine);
 604
 605             // Go down a level
 606             if (TermChar == '{')
 607             {
 608                if (StackPos <= 100)
 609                   Stack[StackPos++] = ParentTag;
 610
 611                /* Make sectional tags incorperate the section into the
 612                   tag string */
 613                if (AsSectional == true && Word.empty() == false)
 614                {
 615                   Tag += "::" ;
 616                   Tag += Word;
 617                   Word = "";
 618                }
 619
 620                if (ParentTag.empty() == true)
 621                   ParentTag = Tag;
 622                else
 623                   ParentTag += string("::") + Tag;
 624                Tag = string();
 625             }
 626
 627             // Generate the item name
 628             string Item;
 629             if (ParentTag.empty() == true)
 630                Item = Tag;
 631             else
 632             {
 633                if (TermChar != '{' || Tag.empty() == false)
 634                   Item = ParentTag + "::" + Tag;
 635                else
 636                   Item = ParentTag;
 637             }
 638
 639             // Specials
 640             if (Tag.length() >= 1 && Tag[0] == '#')
 641             {
 642                if (ParentTag.empty() == false)
 643                   return _error->Error(_("Syntax error %s:%u: Directives can only be done at the top level"),FName.c_str(),CurLine);
 644                Tag.erase(Tag.begin());
 645                if (Tag == "clear")
 646                   Conf.Clear(Word);
 647                else if (Tag == "include")
 648                {
 649                   if (Depth > 10)
 650                      return _error->Error(_("Syntax error %s:%u: Too many nested includes"),FName.c_str(),CurLine);
 651                   if (Word.length() > 2 && Word.end()[-1] == '/')
 652                   {
 653                      if (ReadConfigDir(Conf,Word,AsSectional,Depth+1) == false)
 654                         return _error->Error(_("Syntax error %s:%u: Included from here"),FName.c_str(),CurLine);
 655                   }
 656                   else
 657                   {
 658                      if (ReadConfigFile(Conf,Word,AsSectional,Depth+1) == false)
 659                         return _error->Error(_("Syntax error %s:%u: Included from here"),FName.c_str(),CurLine);
 660                   }
 661                }
 662                else
 663                   return _error->Error(_("Syntax error %s:%u: Unsupported directive '%s'"),FName.c_str(),CurLine,Tag.c_str());
 664             }
 665             else
 666             {
 667                // Set the item in the configuration class
 668                if (NoWord == false)
 669                   Conf.Set(Item,Word);
 670             }
 671
 672             // Empty the buffer
 673             LineBuffer = string();
 674
 675             // Move up a tag, but only if there is no bit to parse
 676             if (TermChar == '}')
 677             {
 678                if (StackPos == 0)
 679                   ParentTag = string();
 680                else
 681                   ParentTag = Stack[--StackPos];
 682             }
 683
 684          }
 685          else
 686             I++;
 687       }
 688
 689       // Store the fragment
 690       const char *Stripd = _strstrip(Buffer);
 691       if (*Stripd != 0 && LineBuffer.empty() == false)
 692          LineBuffer += " ";
 693       LineBuffer += Stripd;
 694    }
 695
 696    if (LineBuffer.empty() == false)
 697       return _error->Error(_("Syntax error %s:%u: Extra junk at end of file"),FName.c_str(),CurLine);
 698    return true;
 699 }
 700                                                                         /*}}}*/
 701 // ReadConfigDir - Read a directory of config files                     /*{{{*/
 702 // ---------------------------------------------------------------------
 703 /* */
 704 bool ReadConfigDir(Configuration &Conf,string Dir,bool AsSectional,
 705                     unsigned Depth)
 706 {
 707    DIR *D = opendir(Dir.c_str());
 708    if (D == 0)
 709       return _error->Errno("opendir",_("Unable to read %s"),Dir.c_str());
 710
 711    vector<string> List;
 712
 713    for (struct dirent *Ent = readdir(D); Ent != 0; Ent = readdir(D))
 714    {
 715       if (Ent->d_name[0] == '.')
 716          continue;
 717
 718       // Skip bad file names ala run-parts
 719       const char *C = Ent->d_name;
 720       for (; *C != 0; C++)
 721          if (isalpha(*C) == 0 && isdigit(*C) == 0 && *C != '_' && *C != '-')
 722             break;
 723       if (*C != 0)
 724          continue;
 725
 726       // Make sure it is a file and not something else
 727       string File = flCombine(Dir,Ent->d_name);
 728       struct stat St;
 729       if (stat(File.c_str(),&St) != 0 || S_ISREG(St.st_mode) == 0)
 730          continue;
 731
 732       List.push_back(File);
 733    }
 734    closedir(D);
 735
 736    sort(List.begin(),List.end());
 737
 738    // Read the files
 739    for (vector<string>::const_iterator I = List.begin(); I != List.end(); I++)
 740       if (ReadConfigFile(Conf,*I,AsSectional,Depth) == false)
 741          return false;
 742    return true;
 743 }
 744                                                                         /*}}}*/