apt/apt-pkg/versionmatch.cc

// -*- mode: cpp; mode: fold -*-
// Description								/*{{{*/
// $Id: versionmatch.cc,v 1.9 2003/05/19 17:58:26 doogie Exp $
/* ######################################################################

   Version Matching 
   
   This module takes a matching string and a type and locates the version
   record that satisfies the constraint described by the matching string.
   
   ##################################################################### */
									/*}}}*/
// Include Files							/*{{{*/
#include<config.h>

#include <apt-pkg/versionmatch.h>
#include <apt-pkg/strutl.h>
#include <apt-pkg/error.h>
#include <apt-pkg/pkgcache.h>
#include <apt-pkg/cacheiterators.h>

#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <string>
#include <stdio.h>
#include <ctype.h>
#include <fnmatch.h>
#include <regex.h>
									/*}}}*/

using std::string;

// VersionMatch::pkgVersionMatch - Constructor				/*{{{*/
// ---------------------------------------------------------------------
/* Break up the data string according to the selected type */
pkgVersionMatch::pkgVersionMatch(string Data,MatchType Type) : Type(Type)
{
   MatchAll = false;
   VerPrefixMatch = false;
   RelVerPrefixMatch = false;
   
   if (Type == None || Data.length() < 1)
      return;
   
   // Cut up the version representation
   if (Type == Version)
   {
      if (Data.end()[-1] == '*')
      {
	 VerPrefixMatch = true;
	 VerStr = string(Data,0,Data.length()-1);
      }
      else
	 VerStr = Data;
      return;
   }   
   
   if (Type == Release)
   {
      // All empty = match all
      if (Data == "*")
      {
	 MatchAll = true;
	 return;
      }
      
      // Are we a simple specification?
      string::const_iterator I = Data.begin();
      for (; I != Data.end() && *I != '='; ++I);
      if (I == Data.end())
      {
	 // Temporary
	 if (isdigit(Data[0]))
	    RelVerStr = Data;
	 else
	    RelRelease = Data;

	 if (RelVerStr.length() > 0 && RelVerStr.end()[-1] == '*')
	 {
	    RelVerPrefixMatch = true;
	    RelVerStr = string(RelVerStr.begin(),RelVerStr.end()-1);
	 }	 
	 return;
      }
            
      char Spec[300];
      char *Fragments[20];
      snprintf(Spec,sizeof(Spec),"%s",Data.c_str());
      if (TokSplitString(',',Spec,Fragments,
			 sizeof(Fragments)/sizeof(Fragments[0])) == false)
      {
	 Type = None;
	 return;
      }
      
      for (unsigned J = 0; Fragments[J] != 0; J++)
      {
	 if (strlen(Fragments[J]) < 3)
	    continue;

	 if (stringcasecmp(Fragments[J],Fragments[J]+2,"v=") == 0)
	    RelVerStr = Fragments[J]+2;
	 else if (stringcasecmp(Fragments[J],Fragments[J]+2,"o=") == 0)
	    RelOrigin = Fragments[J]+2;
	 else if (stringcasecmp(Fragments[J],Fragments[J]+2,"a=") == 0)
	    RelArchive = Fragments[J]+2;
	 else if (stringcasecmp(Fragments[J],Fragments[J]+2,"n=") == 0)
	    RelCodename = Fragments[J]+2;
	 else if (stringcasecmp(Fragments[J],Fragments[J]+2,"l=") == 0)
	    RelLabel = Fragments[J]+2;
	 else if (stringcasecmp(Fragments[J],Fragments[J]+2,"c=") == 0)
	    RelComponent = Fragments[J]+2;
	 else if (stringcasecmp(Fragments[J],Fragments[J]+2,"b=") == 0)
	    RelArchitecture = Fragments[J]+2;
      }

      if (RelVerStr.end()[-1] == '*')
      {
	 RelVerPrefixMatch = true;
	 RelVerStr = string(RelVerStr.begin(),RelVerStr.end()-1);
      }	 
      return;
   }
   
   if (Type == Origin)
   {
      if (Data[0] == '"' && Data.length() >= 2 && Data.end()[-1] == '"')
	 OrSite = Data.substr(1, Data.length() - 2);
      else
	 OrSite = Data;
      return;
   }   
}
									/*}}}*/
// VersionMatch::MatchVer - Match a version string with prefixing	/*{{{*/
// ---------------------------------------------------------------------
/* */
bool pkgVersionMatch::MatchVer(const char *A,string B,bool Prefix)
{   
   const char *Ab = A;
   const char *Ae = Ab + strlen(A);
   
   // Strings are not a compatible size.
   if (((unsigned)(Ae - Ab) != B.length() && Prefix == false) ||
       (unsigned)(Ae - Ab) < B.length())
      return false;
   
   // Match (leading?)
   if (stringcasecmp(B,Ab,Ab + B.length()) == 0)
      return true;
   
   return false;
}
									/*}}}*/
// VersionMatch::Find - Locate the best match for the select type	/*{{{*/
// ---------------------------------------------------------------------
/* */
pkgCache::VerIterator pkgVersionMatch::Find(pkgCache::PkgIterator Pkg)
{
   pkgCache::VerIterator Ver = Pkg.VersionList();
   for (; Ver.end() == false; ++Ver)
   {
      if (Type == Version)
      {
	 if (MatchVer(Ver.VerStr(),VerStr,VerPrefixMatch) == true)
	    return Ver;
	 if (ExpressionMatches(VerStr, Ver.VerStr()) == true)
	    return Ver;
	 continue;
      }
      
      for (pkgCache::VerFileIterator VF = Ver.FileList(); VF.end() == false; ++VF)
	 if (FileMatch(VF.File()) == true)
	    return Ver;
   }
      
   // This will be Ended by now.
   return Ver;
}

#ifndef FNM_CASEFOLD
#define FNM_CASEFOLD 0
#endif

bool pkgVersionMatch::ExpressionMatches(const char *pattern, const char *string)
{
   if (pattern[0] == '/') {
      size_t length = strlen(pattern);
      if (pattern[length - 1] == '/') {
	 bool res = false;
	 regex_t preg;
	 char *regex = strdup(pattern + 1);
	 regex[length - 2] = '\0';
	 if (regcomp(&preg, regex, REG_EXTENDED | REG_ICASE) != 0) {
	    _error->Warning("Invalid regular expression: %s", regex);
	 } else if (regexec(&preg, string, 0, NULL, 0) == 0) {
	    res = true;
	 }
	 free(regex);
	 regfree(&preg);
	 return res;
      }
   }
   return fnmatch(pattern, string, FNM_CASEFOLD) == 0;
}
bool pkgVersionMatch::ExpressionMatches(const std::string& pattern, const char *string)
{
    return ExpressionMatches(pattern.c_str(), string);
}
									/*}}}*/
// VersionMatch::FileMatch - Match against an index file		/*{{{*/
// ---------------------------------------------------------------------
/* This matcher checks against the release file and the origin location 
   to see if the constraints are met. */
bool pkgVersionMatch::FileMatch(pkgCache::PkgFileIterator File)
{
   if (Type == Release)
   {
      if (MatchAll == true)
	 return true;

/*      cout << RelVerStr << ',' << RelOrigin << ',' << RelArchive << ',' << RelLabel << endl;
      cout << File.Version() << ',' << File.Origin() << ',' << File.Archive() << ',' << File.Label() << endl;*/

      if (RelVerStr.empty() == true && RelOrigin.empty() == true &&
	  RelArchive.empty() == true && RelLabel.empty() == true &&
	  RelRelease.empty() == true && RelCodename.empty() == true &&
	  RelComponent.empty() == true && RelArchitecture.empty() == true)
	 return false;

      if (RelVerStr.empty() == false)
	 if (File->Version == 0 ||
	     (MatchVer(File.Version(),RelVerStr,RelVerPrefixMatch) == false &&
	      ExpressionMatches(RelVerStr, File.Version()) == false))
	    return false;
      if (RelOrigin.empty() == false)
	 if (File->Origin == 0 || !ExpressionMatches(RelOrigin,File.Origin()))
	    return false;
      if (RelArchive.empty() == false)
	 if (File->Archive == 0 ||
	     !ExpressionMatches(RelArchive,File.Archive()))
            return false;
      if (RelCodename.empty() == false)
	 if (File->Codename == 0 ||
	     !ExpressionMatches(RelCodename,File.Codename()))
            return false;
      if (RelRelease.empty() == false)
	 if ((File->Archive == 0 ||
	     !ExpressionMatches(RelRelease,File.Archive())) &&
             (File->Codename == 0 ||
	      !ExpressionMatches(RelRelease,File.Codename())))
	       return false;
      if (RelLabel.empty() == false)
	 if (File->Label == 0 ||
	     !ExpressionMatches(RelLabel,File.Label()))
	    return false;
      if (RelComponent.empty() == false)
	 if (File->Component == 0 ||
	     !ExpressionMatches(RelComponent,File.Component()))
	    return false;
      if (RelArchitecture.empty() == false)
	 if (File->Architecture == 0 ||
	     !ExpressionMatches(RelArchitecture,File.Architecture()))
	    return false;
      return true;
   }

   if (Type == Origin)
   {
      if (OrSite.empty() == false) {
	 if (File->Site == 0)
	    return false;
      } else // so we are talking about file:// or status file
	 if (strcmp(File.Site(),"") == 0 && File->Archive != 0 && strcmp(File.Archive(),"now") == 0) // skip the status file
	    return false;
      return (ExpressionMatches(OrSite, File.Site())); /* both strings match */
   }

   return false;
}
									/*}}}*/