Adding upstream version 2.6.1.upstream/2.6.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1194 insertions, 0 deletions

diff --git a/apt-pkg/contrib/configuration.cc b/apt-pkg/contrib/configuration.cc
new file mode 100644
index 0000000..1134ed6
--- /dev/null
+++ b/apt-pkg/contrib/configuration.cc
@@ -0,0 +1,1194 @@
+// -*- mode: cpp; mode: fold -*-
+// SPDX-License-Identifier: GPL-2.0+
+// Description								/*{{{*/
+/* ######################################################################
+
+   Configuration Class
+   
+   This class provides a configuration file and command line parser
+   for a tree-oriented configuration environment. All runtime configuration
+   is stored in here.
+
+   This file had this historic note, but now includes further changes
+   under the GPL-2.0+:
+
+   This source is placed in the Public Domain, do with it what you will
+   It was originally written by Jason Gunthorpe <jgg@debian.org>.
+
+   ##################################################################### */
+									/*}}}*/
+// Include files							/*{{{*/
+#include <config.h>
+
+#include <apt-pkg/configuration.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/macros.h>
+#include <apt-pkg/strutl.h>
+#include <apt-pkg/string_view.h>
+
+#include <ctype.h>
+#include <regex.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <algorithm>
+#include <array>
+#include <fstream>
+#include <iterator>
+#include <numeric>
+#include <sstream>
+#include <stack>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+#include <apti18n.h>
+
+using namespace std;
+									/*}}}*/
+
+Configuration *_config = new Configuration;
+
+/* TODO: This config verification shouldn't be using a static variable
+   but a Cnf-member – but that would need ABI breaks and stuff and for now
+   that really is an apt-dev-only tool, so it isn't that bad that it is
+   unusable and allaround a bit strange */
+enum class APT_HIDDEN ConfigType { UNDEFINED, INT, BOOL, STRING, STRING_OR_BOOL, STRING_OR_LIST, FILE, DIR, LIST, PROGRAM_PATH = FILE };
+APT_HIDDEN std::unordered_map<std::string, ConfigType> apt_known_config {};
+static std::string getConfigTypeString(ConfigType const type)		/*{{{*/
+{
+   switch (type)
+   {
+      case ConfigType::UNDEFINED: return "UNDEFINED";
+      case ConfigType::INT: return "INT";
+      case ConfigType::BOOL: return "BOOL";
+      case ConfigType::STRING: return "STRING";
+      case ConfigType::STRING_OR_BOOL: return "STRING_OR_BOOL";
+      case ConfigType::FILE: return "FILE";
+      case ConfigType::DIR: return "DIR";
+      case ConfigType::LIST: return "LIST";
+      case ConfigType::STRING_OR_LIST: return "STRING_OR_LIST";
+   }
+   return "UNKNOWN";
+}
+									/*}}}*/
+static ConfigType getConfigType(std::string const &type)		/*{{{*/
+{
+   if (type == "<INT>")
+      return ConfigType::INT;
+   else if (type == "<BOOL>")
+      return ConfigType::BOOL;
+   else if (type == "<STRING>")
+      return ConfigType::STRING;
+   else if (type == "<STRING_OR_BOOL>")
+      return ConfigType::STRING_OR_BOOL;
+   else if (type == "<FILE>")
+      return ConfigType::FILE;
+   else if (type == "<DIR>")
+      return ConfigType::DIR;
+   else if (type == "<LIST>")
+      return ConfigType::LIST;
+   else if (type == "<STRING_OR_LIST>")
+      return ConfigType::STRING_OR_LIST;
+   else if (type == "<PROGRAM_PATH>")
+      return ConfigType::PROGRAM_PATH;
+   return ConfigType::UNDEFINED;
+}
+									/*}}}*/
+// checkFindConfigOptionType - workhorse of option checking		/*{{{*/
+static void checkFindConfigOptionTypeInternal(std::string name, ConfigType const type)
+{
+   std::transform(name.begin(), name.end(), name.begin(), ::tolower);
+   auto known = apt_known_config.find(name);
+   if (known == apt_known_config.cend())
+   {
+      auto const rcolon = name.rfind(':');
+      if (rcolon != std::string::npos)
+      {
+	 known = apt_known_config.find(name.substr(0, rcolon) + ":*");
+	 if (known == apt_known_config.cend())
+	 {
+	    auto const parts = StringSplit(name, "::");
+	    size_t psize = parts.size();
+	    if (psize > 1)
+	    {
+	       for (size_t max = psize; max != 1; --max)
+	       {
+		  std::ostringstream os;
+		  std::copy(parts.begin(), parts.begin() + max, std::ostream_iterator<std::string>(os, "::"));
+		  os << "**";
+		  known = apt_known_config.find(os.str());
+		  if (known != apt_known_config.cend() && known->second == ConfigType::UNDEFINED)
+		     return;
+	       }
+	       for (size_t max = psize - 1; max != 1; --max)
+	       {
+		  std::ostringstream os;
+		  std::copy(parts.begin(), parts.begin() + max - 1, std::ostream_iterator<std::string>(os, "::"));
+		  os << "*::";
+		  std::copy(parts.begin() + max + 1, parts.end() - 1, std::ostream_iterator<std::string>(os, "::"));
+		  os << *(parts.end() - 1);
+		  known = apt_known_config.find(os.str());
+		  if (known != apt_known_config.cend())
+		     break;
+	       }
+	    }
+	 }
+      }
+   }
+   if (known == apt_known_config.cend())
+      _error->Warning("Using unknown config option »%s« of type %s",
+	    name.c_str(), getConfigTypeString(type).c_str());
+   else if (known->second != type)
+   {
+      if (known->second == ConfigType::DIR && type == ConfigType::FILE)
+	 ; // implementation detail
+      else if (type == ConfigType::STRING && (known->second == ConfigType::FILE || known->second == ConfigType::DIR))
+	 ; // TODO: that might be an error or not, we will figure this out later
+      else if (known->second == ConfigType::STRING_OR_BOOL && (type == ConfigType::BOOL || type == ConfigType::STRING))
+	 ;
+      else if (known->second == ConfigType::STRING_OR_LIST && (type == ConfigType::LIST || type == ConfigType::STRING))
+	 ;
+      else
+	 _error->Warning("Using config option »%s« of type %s as a type %s",
+	       name.c_str(), getConfigTypeString(known->second).c_str(), getConfigTypeString(type).c_str());
+   }
+}
+static void checkFindConfigOptionType(char const * const name, ConfigType const type)
+{
+   if (apt_known_config.empty())
+      return;
+   checkFindConfigOptionTypeInternal(name, type);
+}
+									/*}}}*/
+static bool LoadConfigurationIndex(std::string const &filename)		/*{{{*/
+{
+   apt_known_config.clear();
+   if (filename.empty())
+      return true;
+   Configuration Idx;
+   if (ReadConfigFile(Idx, filename) == false)
+      return false;
+
+   Configuration::Item const * Top = Idx.Tree(nullptr);
+   if (unlikely(Top == nullptr))
+      return false;
+
+   do {
+      if (Top->Value.empty() == false)
+      {
+	 std::string fulltag = Top->FullTag();
+	 std::transform(fulltag.begin(), fulltag.end(), fulltag.begin(), ::tolower);
+	 apt_known_config.emplace(std::move(fulltag), getConfigType(Top->Value));
+      }
+
+      if (Top->Child != nullptr)
+      {
+	 Top = Top->Child;
+	 continue;
+      }
+
+      while (Top != nullptr && Top->Next == nullptr)
+	 Top = Top->Parent;
+      if (Top != nullptr)
+	 Top = Top->Next;
+   } while (Top != nullptr);
+
+   return true;
+}
+									/*}}}*/
+
+// Configuration::Configuration - Constructor				/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+Configuration::Configuration() : ToFree(true)
+{
+   Root = new Item;
+}
+Configuration::Configuration(const Item *Root) : Root((Item *)Root), ToFree(false)
+{
+}
+									/*}}}*/
+// Configuration::~Configuration - Destructor				/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+Configuration::~Configuration()
+{
+   if (ToFree == false)
+      return;
+   
+   Item *Top = Root;
+   for (; Top != 0;)
+   {
+      if (Top->Child != 0)
+      {
+	 Top = Top->Child;
+	 continue;
+      }
+            
+      while (Top != 0 && Top->Next == 0)
+      {
+	 Item *Parent = Top->Parent;
+	 delete Top;
+	 Top = Parent;
+      }      
+      if (Top != 0)
+      {
+	 Item *Next = Top->Next;
+	 delete Top;
+	 Top = Next;
+      }
+   }
+}
+									/*}}}*/
+// Configuration::Lookup - Lookup a single item				/*{{{*/
+// ---------------------------------------------------------------------
+/* This will lookup a single item by name below another item. It is a 
+   helper function for the main lookup function */
+Configuration::Item *Configuration::Lookup(Item *Head,const char *S,
+					   unsigned long const &Len,bool const &Create)
+{
+   int Res = 1;
+   Item *I = Head->Child;
+   Item **Last = &Head->Child;
+   
+   // Empty strings match nothing. They are used for lists.
+   if (Len != 0)
+   {
+      for (; I != 0; Last = &I->Next, I = I->Next)
+	 if (Len == I->Tag.length() && (Res = stringcasecmp(I->Tag,S,S + Len)) == 0)
+	    break;
+   }
+   else
+      for (; I != 0; Last = &I->Next, I = I->Next);
+      
+   if (Res == 0)
+      return I;
+   if (Create == false)
+      return 0;
+   
+   I = new Item;
+   I->Tag.assign(S,Len);
+   I->Next = *Last;
+   I->Parent = Head;
+   *Last = I;
+   return I;
+}
+									/*}}}*/
+// Configuration::Lookup - Lookup a fully scoped item			/*{{{*/
+// ---------------------------------------------------------------------
+/* This performs a fully scoped lookup of a given name, possibly creating
+   new items */
+Configuration::Item *Configuration::Lookup(const char *Name,bool const &Create)
+{
+   if (Name == 0)
+      return Root->Child;
+   
+   const char *Start = Name;
+   const char *End = Start + strlen(Name);
+   const char *TagEnd = Name;
+   Item *Itm = Root;
+   for (; End - TagEnd >= 2; TagEnd++)
+   {
+      if (TagEnd[0] == ':' && TagEnd[1] == ':')
+      {
+	 Itm = Lookup(Itm,Start,TagEnd - Start,Create);
+	 if (Itm == 0)
+	    return 0;
+	 TagEnd = Start = TagEnd + 2;	 
+      }
+   }   
+
+   // This must be a trailing ::, we create unique items in a list
+   if (End - Start == 0)
+   {
+      if (Create == false)
+	 return 0;
+   }
+   
+   Itm = Lookup(Itm,Start,End - Start,Create);
+   return Itm;
+}
+									/*}}}*/
+// Configuration::Find - Find a value					/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+string Configuration::Find(const char *Name,const char *Default) const
+{
+   checkFindConfigOptionType(Name, ConfigType::STRING);
+   const Item *Itm = Lookup(Name);
+   if (Itm == 0 || Itm->Value.empty() == true)
+   {
+      if (Default == 0)
+	 return "";
+      else
+	 return Default;
+   }
+   
+   return Itm->Value;
+}
+									/*}}}*/
+// Configuration::FindFile - Find a Filename				/*{{{*/
+// ---------------------------------------------------------------------
+/* Directories are stored as the base dir in the Parent node and the
+   sub directory in sub nodes with the final node being the end filename
+ */
+string Configuration::FindFile(const char *Name,const char *Default) const
+{
+   checkFindConfigOptionType(Name, ConfigType::FILE);
+   const Item *RootItem = Lookup("RootDir");
+   std::string result =  (RootItem == 0) ? "" : RootItem->Value;
+   if(result.empty() == false && result[result.size() - 1] != '/')
+     result.push_back('/');
+
+   const Item *Itm = Lookup(Name);
+   if (Itm == 0 || Itm->Value.empty() == true)
+   {
+      if (Default != 0)
+	 result.append(Default);
+   }
+   else
+   {
+      string val = Itm->Value;
+      while (Itm->Parent != 0)
+      {
+	 if (Itm->Parent->Value.empty() == true)
+	 {
+	    Itm = Itm->Parent;
+	    continue;
+	 }
+
+	 // Absolute
+	 if (val.length() >= 1 && val[0] == '/')
+	 {
+	    if (val.compare(0, 9, "/dev/null") == 0)
+	       val.erase(9);
+	    break;
+	 }
+
+	 // ~/foo or ./foo
+	 if (val.length() >= 2 && (val[0] == '~' || val[0] == '.') && val[1] == '/')
+	    break;
+
+	 // ../foo
+	 if (val.length() >= 3 && val[0] == '.' && val[1] == '.' && val[2] == '/')
+	    break;
+
+	 if (Itm->Parent->Value.end()[-1] != '/')
+	    val.insert(0, "/");
+
+	 val.insert(0, Itm->Parent->Value);
+	 Itm = Itm->Parent;
+      }
+      result.append(val);
+   }
+   return flNormalize(result);
+}
+									/*}}}*/
+// Configuration::FindDir - Find a directory name			/*{{{*/
+// ---------------------------------------------------------------------
+/* This is like findfile execept the result is terminated in a / */
+string Configuration::FindDir(const char *Name,const char *Default) const
+{
+   checkFindConfigOptionType(Name, ConfigType::DIR);
+   string Res = FindFile(Name,Default);
+   if (Res.end()[-1] != '/')
+   {
+      size_t const found = Res.rfind("/dev/null");
+      if (found != string::npos && found == Res.size() - 9)
+	 return Res; // /dev/null returning
+      return Res + '/';
+   }
+   return Res;
+}
+									/*}}}*/
+// Configuration::FindVector - Find a vector of values			/*{{{*/
+// ---------------------------------------------------------------------
+/* Returns a vector of config values under the given item */
+vector<string> Configuration::FindVector(const char *Name, std::string const &Default, bool const Keys) const
+{
+   checkFindConfigOptionType(Name, ConfigType::LIST);
+   vector<string> Vec;
+   const Item *Top = Lookup(Name);
+   if (Top == NULL)
+      return VectorizeString(Default, ',');
+
+   if (Top->Value.empty() == false)
+      return VectorizeString(Top->Value, ',');
+
+   Item *I = Top->Child;
+   while(I != NULL)
+   {
+      Vec.push_back(Keys ? I->Tag : I->Value);
+      I = I->Next;
+   }
+   if (Vec.empty() == true)
+      return VectorizeString(Default, ',');
+
+   return Vec;
+}
+									/*}}}*/
+// Configuration::FindI - Find an integer value				/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+int Configuration::FindI(const char *Name,int const &Default) const
+{
+   checkFindConfigOptionType(Name, ConfigType::INT);
+   const Item *Itm = Lookup(Name);
+   if (Itm == 0 || Itm->Value.empty() == true)
+      return Default;
+   
+   char *End;
+   int Res = strtol(Itm->Value.c_str(),&End,0);
+   if (End == Itm->Value.c_str())
+      return Default;
+   
+   return Res;
+}
+									/*}}}*/
+// Configuration::FindB - Find a boolean type				/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool Configuration::FindB(const char *Name,bool const &Default) const
+{
+   checkFindConfigOptionType(Name, ConfigType::BOOL);
+   const Item *Itm = Lookup(Name);
+   if (Itm == 0 || Itm->Value.empty() == true)
+      return Default;
+   
+   return StringToBool(Itm->Value,Default);
+}
+									/*}}}*/
+// Configuration::FindAny - Find an arbitrary type			/*{{{*/
+// ---------------------------------------------------------------------
+/* a key suffix of /f, /d, /b or /i calls Find{File,Dir,B,I} */
+string Configuration::FindAny(const char *Name,const char *Default) const
+{
+   string key = Name;
+   char type = 0;
+
+   if (key.size() > 2 && key.end()[-2] == '/')
+   {
+      type = key.end()[-1];
+      key.resize(key.size() - 2);
+   }
+
+   switch (type)
+   {
+      // file
+      case 'f': 
+      return FindFile(key.c_str(), Default);
+      
+      // directory
+      case 'd': 
+      return FindDir(key.c_str(), Default);
+      
+      // bool
+      case 'b': 
+      return FindB(key, Default) ? "true" : "false";
+      
+      // int
+      case 'i': 
+      {
+	 char buf[16];
+	 snprintf(buf, sizeof(buf)-1, "%d", FindI(key, Default ? atoi(Default) : 0 ));
+	 return buf;
+      }
+   }
+
+   // fallback
+   return Find(Name, Default);
+}
+									/*}}}*/
+// Configuration::CndSet - Conditional Set a value			/*{{{*/
+// ---------------------------------------------------------------------
+/* This will not overwrite */
+void Configuration::CndSet(const char *Name,const string &Value)
+{
+   Item *Itm = Lookup(Name,true);
+   if (Itm == 0)
+      return;
+   if (Itm->Value.empty() == true)
+      Itm->Value = Value;
+}
+									/*}}}*/
+// Configuration::Set - Set an integer value				/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+void Configuration::CndSet(const char *Name,int const Value)
+{
+   Item *Itm = Lookup(Name,true);
+   if (Itm == 0 || Itm->Value.empty() == false)
+      return;
+   char S[300];
+   snprintf(S,sizeof(S),"%i",Value);
+   Itm->Value = S;
+}
+									/*}}}*/
+// Configuration::Set - Set a value					/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+void Configuration::Set(const char *Name,const string &Value)
+{
+   Item *Itm = Lookup(Name,true);
+   if (Itm == 0)
+      return;
+   Itm->Value = Value;
+}
+									/*}}}*/
+// Configuration::Set - Set an integer value				/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+void Configuration::Set(const char *Name,int const &Value)
+{
+   Item *Itm = Lookup(Name,true);
+   if (Itm == 0)
+      return;
+   char S[300];
+   snprintf(S,sizeof(S),"%i",Value);
+   Itm->Value = S;
+}
+									/*}}}*/
+// Configuration::Clear - Clear an single value from a list	        /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+void Configuration::Clear(string const &Name, int const &Value)
+{
+   char S[300];
+   snprintf(S,sizeof(S),"%i",Value);
+   Clear(Name, S);
+}
+									/*}}}*/
+// Configuration::Clear - Clear an single value from a list	        /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+void Configuration::Clear(string const &Name, string const &Value)
+{
+   Item *Top = Lookup(Name.c_str(),false);
+   if (Top == 0 || Top->Child == 0)
+      return;
+
+   Item *Tmp, *Prev, *I;
+   Prev = I = Top->Child;
+
+   while(I != NULL)
+   {
+      if(I->Value == Value)
+      {
+	 Tmp = I;
+	 // was first element, point parent to new first element
+	 if(Top->Child == Tmp)
+	    Top->Child = I->Next;
+	 I = I->Next;
+	 Prev->Next = I;
+	 delete Tmp;
+      } else {
+	 Prev = I;
+	 I = I->Next;
+      }
+   }
+     
+}
+									/*}}}*/
+// Configuration::Clear - Clear everything				/*{{{*/
+// ---------------------------------------------------------------------
+void Configuration::Clear()
+{
+   const Configuration::Item *Top = Tree(0);
+   while( Top != 0 )
+   {
+      Clear(Top->FullTag());
+      Top = Top->Next;
+   }
+}
+									/*}}}*/
+// Configuration::Clear - Clear an entire tree				/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+void Configuration::Clear(string const &Name)
+{
+   Item *Top = Lookup(Name.c_str(),false);
+   if (Top == 0) 
+      return;
+
+   Top->Value.clear();
+   Item *Stop = Top;
+   Top = Top->Child;
+   Stop->Child = 0;
+   for (; Top != 0;)
+   {
+      if (Top->Child != 0)
+      {
+	 Top = Top->Child;
+	 continue;
+      }
+
+      while (Top != 0 && Top->Next == 0)
+      {
+	 Item *Tmp = Top;
+	 Top = Top->Parent;
+	 delete Tmp;
+	 
+	 if (Top == Stop)
+	    return;
+      }
+      
+      Item *Tmp = Top;
+      if (Top != 0)
+	 Top = Top->Next;
+      delete Tmp;
+   }
+}
+									/*}}}*/
+void Configuration::MoveSubTree(char const * const OldRootName, char const * const NewRootName)/*{{{*/
+{
+   // prevent NewRoot being a subtree of OldRoot
+   if (OldRootName == nullptr)
+      return;
+   if (NewRootName != nullptr)
+   {
+      if (strcmp(OldRootName, NewRootName) == 0)
+	 return;
+      std::string const oldroot = std::string(OldRootName) + "::";
+      if (strcasestr(NewRootName, oldroot.c_str()) != NULL)
+	 return;
+   }
+
+   Item * Top;
+   Item const * const OldRoot = Top = Lookup(OldRootName, false);
+   if (Top == nullptr)
+      return;
+   std::string NewRoot;
+   if (NewRootName != nullptr)
+      NewRoot.append(NewRootName).append("::");
+
+   Top->Value.clear();
+   Item * const Stop = Top;
+   Top = Top->Child;
+   Stop->Child = 0;
+   for (; Top != 0;)
+   {
+      if (Top->Child != 0)
+      {
+	 Top = Top->Child;
+	 continue;
+      }
+
+      while (Top != 0 && Top->Next == 0)
+      {
+	 Set(NewRoot + Top->FullTag(OldRoot), Top->Value);
+	 Item const * const Tmp = Top;
+	 Top = Top->Parent;
+	 delete Tmp;
+
+	 if (Top == Stop)
+	    return;
+      }
+
+      Set(NewRoot + Top->FullTag(OldRoot), Top->Value);
+      Item const * const Tmp = Top;
+      if (Top != 0)
+	 Top = Top->Next;
+      delete Tmp;
+   }
+}
+									/*}}}*/
+// Configuration::Exists - Returns true if the Name exists		/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool Configuration::Exists(const char *Name) const
+{
+   const Item *Itm = Lookup(Name);
+   if (Itm == 0)
+      return false;
+   return true;
+}
+									/*}}}*/
+// Configuration::ExistsAny - Returns true if the Name, possibly	/*{{{*/
+// ---------------------------------------------------------------------
+/* qualified by /[fdbi] exists */
+bool Configuration::ExistsAny(const char *Name) const
+{
+   string key = Name;
+
+   if (key.size() > 2 && key.end()[-2] == '/')
+   {
+      if (key.find_first_of("fdbi",key.size()-1) < key.size())
+      {
+         key.resize(key.size() - 2);
+         if (Exists(key.c_str()))
+            return true;
+      }
+      else
+      {
+         _error->Warning(_("Unrecognized type abbreviation: '%c'"), key.end()[-3]);
+      }
+   }
+   return Exists(Name);
+}
+									/*}}}*/
+// Configuration::Dump - Dump the config				/*{{{*/
+// ---------------------------------------------------------------------
+/* Dump the entire configuration space */
+void Configuration::Dump(ostream& str)
+{
+   Dump(str, NULL, "%F \"%v\";\n", true);
+}
+void Configuration::Dump(ostream& str, char const * const root,
+			 char const * const formatstr, bool const emptyValue)
+{
+   const Configuration::Item* Top = Tree(root);
+   if (Top == 0)
+      return;
+   const Configuration::Item* const Root = (root == NULL) ? NULL : Top;
+   std::vector<std::string> const format = VectorizeString(formatstr, '%');
+
+   /* Write out all of the configuration directives by walking the
+      configuration tree */
+   do {
+      if (emptyValue == true || Top->Value.empty() == emptyValue)
+      {
+	 std::vector<std::string>::const_iterator f = format.begin();
+	 str << *f;
+	 for (++f; f != format.end(); ++f)
+	 {
+	    if (f->empty() == true)
+	    {
+	       ++f;
+	       str << '%' << *f;
+	       continue;
+	    }
+	    char const type = (*f)[0];
+	    if (type == 'f')
+	       str << Top->FullTag();
+	    else if (type == 't')
+	       str << Top->Tag;
+	    else if (type == 'v')
+	       str << Top->Value;
+	    else if (type == 'F')
+	       str << QuoteString(Top->FullTag(), "=\"\n");
+	    else if (type == 'T')
+	       str << QuoteString(Top->Tag, "=\"\n");
+	    else if (type == 'V')
+	       str << QuoteString(Top->Value, "=\"\n");
+	    else if (type == 'n')
+	       str << "\n";
+	    else if (type == 'N')
+	       str << "\t";
+	    else
+	       str << '%' << type;
+	    str << f->c_str() + 1;
+	 }
+      }
+
+      if (Top->Child != 0)
+      {
+	 Top = Top->Child;
+	 continue;
+      }
+
+      while (Top != 0 && Top->Next == 0)
+	 Top = Top->Parent;
+      if (Top != 0)
+	 Top = Top->Next;
+
+      if (Root != NULL)
+      {
+	 const Configuration::Item* I = Top;
+	 while(I != 0)
+	 {
+	    if (I == Root)
+	       break;
+	    else
+	       I = I->Parent;
+	 }
+	 if (I == 0)
+	    break;
+      }
+   } while (Top != 0);
+}
+									/*}}}*/
+
+// Configuration::Item::FullTag - Return the fully scoped tag		/*{{{*/
+// ---------------------------------------------------------------------
+/* Stop sets an optional max recursion depth if this item is being viewed as
+   part of a sub tree. */
+string Configuration::Item::FullTag(const Item *Stop) const
+{
+   if (Parent == 0 || Parent->Parent == 0 || Parent == Stop)
+      return Tag;
+   return Parent->FullTag(Stop) + "::" + Tag;
+}
+									/*}}}*/
+
+// ReadConfigFile - Read a configuration file				/*{{{*/
+// ---------------------------------------------------------------------
+/* The configuration format is very much like the named.conf format
+   used in bind8, in fact this routine can parse most named.conf files. 
+   Sectional config files are like bind's named.conf where there are 
+   sections like 'zone "foo.org" { .. };' This causes each section to be
+   added in with a tag like "zone::foo.org" instead of being split 
+   tag/value. AsSectional enables Sectional parsing.*/
+static void leaveCurrentScope(std::stack<std::string> &Stack, std::string &ParentTag)
+{
+   if (Stack.empty())
+      ParentTag.clear();
+   else
+   {
+      ParentTag = Stack.top();
+      Stack.pop();
+   }
+}
+bool ReadConfigFile(Configuration &Conf,const string &FName,bool const &AsSectional,
+		    unsigned const &Depth)
+{
+   // Open the stream for reading
+   FileFd F;
+   if (OpenConfigurationFileFd(FName, F) == false)
+      return false;
+
+   string LineBuffer;
+   std::stack<std::string> Stack;
+
+   // Parser state
+   string ParentTag;
+
+   int CurLine = 0;
+   bool InComment = false;
+   while (F.Eof() == false)
+   {
+      // The raw input line.
+      std::string Input;
+      if (F.ReadLine(Input) == false)
+	 Input.clear();
+      // The input line with comments stripped.
+      std::string Fragment;
+
+      // Expand tabs in the input line and remove leading and trailing whitespace.
+      Input = APT::String::Strip(SubstVar(Input, "\t", "        "));
+      CurLine++;
+
+      // Now strip comments; if the whole line is contained in a
+      // comment, skip this line.
+      APT::StringView Line{Input.data(), Input.size()};
+
+      // continued Multi line comment
+      if (InComment)
+      {
+	 size_t end = Line.find("*/");
+	 if (end != APT::StringView::npos)
+	 {
+	    Line.remove_prefix(end + 2);
+	    InComment = false;
+	 }
+	 else
+	    continue;
+      }
+
+      // Discard single line comments
+      {
+	 size_t start = 0;
+	 while ((start = Line.find("//", start)) != APT::StringView::npos)
+	 {
+	    if (std::count(Line.begin(), Line.begin() + start, '"') % 2 != 0)
+	    {
+	       ++start;
+	       continue;
+	    }
+	    Line.remove_suffix(Line.length() - start);
+	    break;
+	 }
+	 using APT::operator""_sv;
+	 constexpr std::array<APT::StringView, 3> magicComments { "clear"_sv, "include"_sv, "x-apt-configure-index"_sv };
+	 start = 0;
+	 while ((start = Line.find('#', start)) != APT::StringView::npos)
+	 {
+	    if (std::count(Line.begin(), Line.begin() + start, '"') % 2 != 0 ||
+		std::any_of(magicComments.begin(), magicComments.end(), [&](auto const m) { return Line.compare(start+1, m.length(), m) == 0; }))
+	    {
+	       ++start;
+	       continue;
+	    }
+	    Line.remove_suffix(Line.length() - start);
+	    break;
+	 }
+      }
+
+      // Look for multi line comments and build up the
+      // fragment.
+      Fragment.reserve(Line.length());
+      {
+	 size_t start = 0;
+	 while ((start = Line.find("/*", start)) != APT::StringView::npos)
+	 {
+	    if (std::count(Line.begin(), Line.begin() + start, '"') % 2 != 0)
+	    {
+	       start += 2;
+	       continue;
+	    }
+	    Fragment.append(Line.data(), start);
+	    auto const end = Line.find("*/", start + 2);
+	    if (end == APT::StringView::npos)
+	    {
+	       Line.clear();
+	       InComment = true;
+	       break;
+	    }
+	    else
+	       Line.remove_prefix(end + 2);
+	    start = 0;
+	 }
+	 if (not Line.empty())
+	    Fragment.append(Line.data(), Line.length());
+      }
+
+      // Skip blank lines.
+      if (Fragment.empty())
+	 continue;
+
+      // The line has actual content; interpret what it means.
+      bool InQuote = false;
+      auto Start = Fragment.cbegin();
+      auto End = Fragment.cend();
+      for (std::string::const_iterator I = Start;
+	   I != End; ++I)
+      {
+	 if (*I == '"')
+	    InQuote = !InQuote;
+
+	 if (InQuote == false && (*I == '{' || *I == ';' || *I == '}'))
+	 {
+	    // Put the last fragment into the buffer
+	    std::string::const_iterator NonWhitespaceStart = Start;
+	    std::string::const_iterator NonWhitespaceStop = I;
+	    for (; NonWhitespaceStart != I && isspace(*NonWhitespaceStart) != 0; ++NonWhitespaceStart)
+	      ;
+	    for (; NonWhitespaceStop != NonWhitespaceStart && isspace(NonWhitespaceStop[-1]) != 0; --NonWhitespaceStop)
+	      ;
+	    if (LineBuffer.empty() == false && NonWhitespaceStop - NonWhitespaceStart != 0)
+	       LineBuffer += ' ';
+	    LineBuffer += string(NonWhitespaceStart, NonWhitespaceStop);
+
+	    // Drop this from the input string, saving the character
+	    // that terminated the construct we just closed. (i.e., a
+	    // brace or a semicolon)
+	    char TermChar = *I;
+	    Start = I + 1;
+
+	    // Syntax Error
+	    if (TermChar == '{' && LineBuffer.empty() == true)
+	       return _error->Error(_("Syntax error %s:%u: Block starts with no name."),FName.c_str(),CurLine);
+
+	    // No string on this line
+	    if (LineBuffer.empty() == true)
+	    {
+	       if (TermChar == '}')
+		  leaveCurrentScope(Stack, ParentTag);
+	       continue;
+	    }
+
+	    // Parse off the tag
+	    string Tag;
+	    const char *Pos = LineBuffer.c_str();
+	    if (ParseQuoteWord(Pos,Tag) == false)
+	       return _error->Error(_("Syntax error %s:%u: Malformed tag"),FName.c_str(),CurLine);
+
+	    // Parse off the word
+	    string Word;
+	    bool NoWord = false;
+	    if (ParseCWord(Pos,Word) == false &&
+		ParseQuoteWord(Pos,Word) == false)
+	    {
+	       if (TermChar != '{')
+	       {
+		  Word = Tag;
+		  Tag = "";
+	       }
+	       else
+		  NoWord = true;
+	    }
+	    if (strlen(Pos) != 0)
+	       return _error->Error(_("Syntax error %s:%u: Extra junk after value"),FName.c_str(),CurLine);
+
+	    // Go down a level
+	    if (TermChar == '{')
+	    {
+	       Stack.push(ParentTag);
+
+	       /* Make sectional tags incorporate the section into the
+	          tag string */
+	       if (AsSectional == true && Word.empty() == false)
+	       {
+		  Tag.append("::").append(Word);
+		  Word.clear();
+	       }
+
+	       if (ParentTag.empty() == true)
+		  ParentTag = Tag;
+	       else
+		  ParentTag.append("::").append(Tag);
+	       Tag.clear();
+	    }
+
+	    // Generate the item name
+	    string Item;
+	    if (ParentTag.empty() == true)
+	       Item = Tag;
+	    else
+	    {
+	       if (TermChar != '{' || Tag.empty() == false)
+		  Item = ParentTag + "::" + Tag;
+	       else
+		  Item = ParentTag;
+	    }
+
+	    // Specials
+	    if (Tag.length() >= 1 && Tag[0] == '#')
+	    {
+	       if (ParentTag.empty() == false)
+		  return _error->Error(_("Syntax error %s:%u: Directives can only be done at the top level"),FName.c_str(),CurLine);
+	       Tag.erase(Tag.begin());
+	       if (Tag == "clear")
+		  Conf.Clear(Word);
+	       else if (Tag == "include")
+	       {
+		  if (Depth > 10)
+		     return _error->Error(_("Syntax error %s:%u: Too many nested includes"),FName.c_str(),CurLine);
+		  if (Word.length() > 2 && Word.end()[-1] == '/')
+		  {
+		     if (ReadConfigDir(Conf,Word,AsSectional,Depth+1) == false)
+			return _error->Error(_("Syntax error %s:%u: Included from here"),FName.c_str(),CurLine);
+		  }
+		  else
+		  {
+		     if (ReadConfigFile(Conf,Word,AsSectional,Depth+1) == false)
+			return _error->Error(_("Syntax error %s:%u: Included from here"),FName.c_str(),CurLine);
+		  }
+	       }
+	       else if (Tag == "x-apt-configure-index")
+	       {
+		  if (LoadConfigurationIndex(Word) == false)
+		     return _error->Warning("Loading the configure index %s in file %s:%u failed!", Word.c_str(), FName.c_str(), CurLine);
+	       }
+	       else
+		  return _error->Error(_("Syntax error %s:%u: Unsupported directive '%s'"),FName.c_str(),CurLine,Tag.c_str());
+	    }
+	    else if (Tag.empty() == true && NoWord == false && Word == "#clear")
+	       return _error->Error(_("Syntax error %s:%u: clear directive requires an option tree as argument"),FName.c_str(),CurLine);
+	    else
+	    {
+	       // Set the item in the configuration class
+	       if (NoWord == false)
+		  Conf.Set(Item,Word);
+	    }
+
+	    // Empty the buffer
+	    LineBuffer.clear();
+
+	    // Move up a tag, but only if there is no bit to parse
+	    if (TermChar == '}')
+	       leaveCurrentScope(Stack, ParentTag);
+	 }
+      }
+
+      // Store the remaining text, if any, in the current line buffer.
+
+      // NB: could change this to use string-based operations; I'm
+      // using strstrip now to ensure backwards compatibility.
+      //   -- dburrows 2008-04-01
+      {
+	char *Buffer = new char[End - Start + 1];
+	try
+	  {
+	    std::copy(Start, End, Buffer);
+	    Buffer[End - Start] = '\0';
+
+	    const char *Stripd = _strstrip(Buffer);
+	    if (*Stripd != 0 && LineBuffer.empty() == false)
+	      LineBuffer += " ";
+	    LineBuffer += Stripd;
+	  }
+	catch(...)
+	  {
+	    delete[] Buffer;
+	    throw;
+	  }
+	delete[] Buffer;
+      }
+   }
+
+   if (LineBuffer.empty() == false)
+      return _error->Error(_("Syntax error %s:%u: Extra junk at end of file"),FName.c_str(),CurLine);
+   return true;
+}
+									/*}}}*/
+// ReadConfigDir - Read a directory of config files			/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool ReadConfigDir(Configuration &Conf,const string &Dir,
+		   bool const &AsSectional, unsigned const &Depth)
+{
+   _error->PushToStack();
+   auto const files = GetListOfFilesInDir(Dir, "conf", true, true);
+   auto const successfulList = not _error->PendingError();
+   _error->MergeWithStack();
+   return std::accumulate(files.cbegin(), files.cend(), true, [&](bool good, auto const &file) {
+      return ReadConfigFile(Conf, file, AsSectional, Depth) && good;
+   }) && successfulList;
+}
+									/*}}}*/
+// MatchAgainstConfig Constructor					/*{{{*/
+Configuration::MatchAgainstConfig::MatchAgainstConfig(char const * Config)
+{
+   std::vector<std::string> const strings = _config->FindVector(Config);
+   for (std::vector<std::string>::const_iterator s = strings.begin();
+	s != strings.end(); ++s)
+   {
+      regex_t *p = new regex_t;
+      if (regcomp(p, s->c_str(), REG_EXTENDED | REG_ICASE | REG_NOSUB) == 0)
+	 patterns.push_back(p);
+      else
+      {
+	 regfree(p);
+	 delete p;
+	 _error->Warning("Invalid regular expression '%s' in configuration "
+                         "option '%s' will be ignored.",
+                         s->c_str(), Config);
+	 continue;
+      }
+   }
+   if (strings.empty() == true)
+      patterns.push_back(NULL);
+}
+									/*}}}*/
+// MatchAgainstConfig Destructor					/*{{{*/
+Configuration::MatchAgainstConfig::~MatchAgainstConfig()
+{
+   clearPatterns();
+}
+void Configuration::MatchAgainstConfig::clearPatterns()
+{
+   for(std::vector<regex_t *>::const_iterator p = patterns.begin();
+	p != patterns.end(); ++p)
+   {
+      if (*p == NULL) continue;
+      regfree(*p);
+      delete *p;
+   }
+   patterns.clear();
+}
+									/*}}}*/
+// MatchAgainstConfig::Match - returns true if a pattern matches	/*{{{*/
+bool Configuration::MatchAgainstConfig::Match(char const * str) const
+{
+   for(std::vector<regex_t *>::const_iterator p = patterns.begin();
+	p != patterns.end(); ++p)
+      if (*p != NULL && regexec(*p, str, 0, 0, 0) == 0)
+	 return true;
+
+   return false;
+}
+									/*}}}*/