Join with aliencode

Author: jgg
Date: 2001-02-20 07:03:16 GMT
Join with aliencode

1 files changed, 275 insertions, 0 deletions

diff --git a/apt-pkg/policy.cc b/apt-pkg/policy.cc
new file mode 100644
index 000000000..029a37df7
--- /dev/null
+++ b/apt-pkg/policy.cc
@@ -0,0 +1,275 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+// $Id: policy.cc,v 1.2 2001/02/20 07:03:17 jgg Exp $
+/* ######################################################################
+
+   Package Version Policy implementation
+   
+   This is just a really simple wrapper around pkgVersionMatch with
+   some added goodies to manage the list of things..
+   
+   Priority Table:
+   
+   1000 -> inf = Downgradeable priorities
+   1000        = The 'no downgrade' pseduo-status file
+   100 -> 1000 = Standard priorities
+   990         = Config file override package files
+   989         = Start for preference auto-priorities
+   500         = Default package files
+   100         = The status file
+   0 -> 100    = NotAutomatic sources like experimental
+   -inf -> 0   = Never selected   
+   
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#ifdef __GNUG__
+#pragma implementation "apt-pkg/policy.h"
+#endif
+#include <apt-pkg/policy.h>
+#include <apt-pkg/configuration.h>
+#include <apt-pkg/tagfile.h>
+#include <apt-pkg/strutl.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/sptr.h>
+    
+#include <apti18n.h>
+									/*}}}*/
+
+// Policy::Init - Startup and bind to a cache				/*{{{*/
+// ---------------------------------------------------------------------
+/* Set the defaults for operation. The default mode with no loaded policy
+   file matches the V0 policy engine. */
+pkgPolicy::pkgPolicy(pkgCache *Owner) : Pins(0), PFPriority(0), Cache(Owner)
+{
+   PFPriority = new signed short[Owner->Head().PackageFileCount];
+   Pins = new Pin[Owner->Head().PackageCount];
+
+   for (unsigned long I = 0; I != Owner->Head().PackageCount; I++)
+      Pins[I].Type = pkgVersionMatch::None;
+
+   // The config file has a master override.
+   string DefRel = _config->Find("APT::Default-Release");
+   if (DefRel.empty() == false)
+      CreatePin(pkgVersionMatch::Release,"",DefRel,990);
+      
+   InitDefaults();
+}
+									/*}}}*/
+// Policy::InitDefaults - Compute the default selections		/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool pkgPolicy::InitDefaults()
+{   
+   // Initialize the priorities based on the status of the package file
+   for (pkgCache::PkgFileIterator I = Cache->FileBegin(); I != Cache->FileEnd(); I++)
+   {
+      PFPriority[I->ID] = 500;
+      if ((I->Flags & pkgCache::Flag::NotSource) == pkgCache::Flag::NotSource)
+	 PFPriority[I->ID] = 100;
+      else
+	 if ((I->Flags & pkgCache::Flag::NotAutomatic) == pkgCache::Flag::NotAutomatic)
+	    PFPriority[I->ID] = 1;
+   }
+
+   // Apply the defaults..
+   SPtr<bool> Fixed = new bool[Cache->HeaderP->PackageFileCount];
+   memset(Fixed,0,sizeof(*Fixed)*Cache->HeaderP->PackageFileCount);
+   signed Cur = 989;
+   StatusOverride = false;
+   for (vector<Pin>::const_iterator I = Defaults.begin(); I != Defaults.end();
+	I++, Cur--)
+   {
+      pkgVersionMatch Match(I->Data,I->Type);
+      for (pkgCache::PkgFileIterator F = Cache->FileBegin(); F != Cache->FileEnd(); F++)
+      {
+/* hmm?
+ if ((F->Flags & pkgCache::Flag::NotSource) == pkgCache::Flag::NotSource)
+	    continue;*/
+
+	 if (Match.FileMatch(F) == true && Fixed[F->ID] == false)
+	 {
+	    if (I->Priority != 0 && I->Priority > 0)
+	       Cur = I->Priority;
+	    
+	    if (I->Priority < 0)
+	       PFPriority[F->ID] =  I->Priority;
+	    else
+	       PFPriority[F->ID] = Cur;
+	    
+	    if (PFPriority[F->ID] > 1000)
+	       StatusOverride = true;
+	    
+	    Fixed[F->ID] = true;
+	 }      
+      }      
+   }
+
+   if (_config->FindB("Debug::pkgPolicy",false) == true)
+      for (pkgCache::PkgFileIterator F = Cache->FileBegin(); F != Cache->FileEnd(); F++)
+	 cout << "Prio of " << F.FileName() << ' ' << PFPriority[F->ID] << endl; 
+   
+   return true;   
+}
+									/*}}}*/
+// Policy::GetCandidateVer - Get the candidate install version		/*{{{*/
+// ---------------------------------------------------------------------
+/* Evaluate the package pins and the default list to deteremine what the
+   best package is. */
+pkgCache::VerIterator pkgPolicy::GetCandidateVer(pkgCache::PkgIterator Pkg)
+{
+   const Pin &PPkg = Pins[Pkg->ID];
+   
+   // Look for a package pin and evaluate it.
+   signed Max = 0;
+   pkgCache::VerIterator Pref(*Cache);
+   if (PPkg.Type != pkgVersionMatch::None)
+   {
+      pkgVersionMatch Match(PPkg.Data,PPkg.Type);
+      Pref = Match.Find(Pkg);
+      Max = PPkg.Priority;
+      if (PPkg.Priority == 0)
+	 Max = 989;
+   }
+      
+   /* Falling through to the default version.. Setting Max to zero
+      effectively excludes everything <= 0 which are the non-automatic
+      priorities.. The status file is given a prio of 100 which will exclude
+      not-automatic sources, except in a single shot not-installed mode.
+      The second pseduo-status file is at prio 1000, above which will permit
+      the user to force-downgrade things.
+      
+      The user pin is subject to the same priority rules as default 
+      selections. Thus there are two ways to create a pin - a pin that
+      tracks the default when the default is taken away, and a permanent
+      pin that stays at that setting.
+    */
+   for (pkgCache::VerIterator Ver = Pkg.VersionList(); Ver.end() == false; Ver++)
+   {      
+      for (pkgCache::VerFileIterator VF = Ver.FileList(); VF.end() == false; VF++)
+      {
+	 signed Prio = PFPriority[VF.File()->ID];
+	 if (Prio > Max)
+	 {
+	    Pref = Ver;
+	    Max = Prio;
+	 }	 
+      }      
+      
+      if (Pkg.CurrentVer() == Ver && Max < 1000)
+      {
+	 /* Elevate our current selection (or the status file itself)
+	    to the Pseudo-status priority. */
+	 if (Pref.end() == true)
+	    Pref = Ver;
+	 Max = 1000;
+	 
+	 // Fast path optimize.
+	 if (StatusOverride == false)
+	    break;
+      }            
+   }
+   
+   return Pref;
+}
+									/*}}}*/
+// Policy::CreatePin - Create an entry in the pin table..		/*{{{*/
+// ---------------------------------------------------------------------
+/* For performance we have 3 tables, the default table, the main cache
+   table (hashed to the cache). A blank package name indicates the pin
+   belongs to the default table. Order of insertion matters here, the
+   earlier defaults override later ones. */
+void pkgPolicy::CreatePin(pkgVersionMatch::MatchType Type,string Name,
+			  string Data,signed short Priority)
+{
+   pkgCache::PkgIterator Pkg = Cache->FindPkg(Name);
+   Pin *P = 0;
+   
+   if (Name.empty() == true)
+      P = Defaults.insert(Defaults.end());
+   else
+   {
+      // Get a spot to put the pin
+      if (Pkg.end() == true)
+      {
+	 // Check the unmatched table
+	 for (vector<PkgPin>::iterator I = Unmatched.begin(); 
+	      I != Unmatched.end() && P == 0; I++)
+	    if (I->Pkg == Name)
+	       P = I;
+	 
+	 if (P == 0)
+	    P = Unmatched.insert(Unmatched.end());      
+      }
+      else
+      {
+	 P = Pins + Pkg->ID;
+      }      
+   }
+   
+   // Set..
+   P->Type = Type;
+   P->Priority = Priority;
+   P->Data = Data;
+}
+									/*}}}*/
+
+// ReadPinFile - Load the pin file into a Policy			/*{{{*/
+// ---------------------------------------------------------------------
+/* I'd like to see the preferences file store more than just pin information
+   but right now that is the only stuff I have to store. Later there will
+   have to be some kind of combined super parser to get the data into all
+   the right classes.. */
+bool ReadPinFile(pkgPolicy &Plcy,string File)
+{
+   if (File.empty() == true)
+      File = _config->FindFile("Dir::Etc::Preferences");
+
+   if (FileExists(File) == false)
+      return true;
+   
+   FileFd Fd(File,FileFd::ReadOnly);
+   pkgTagFile TF(&Fd);
+   if (_error->PendingError() == true)
+      return false;
+   
+   pkgTagSection Tags;
+   while (TF.Step(Tags) == true)
+   {
+      string Name = Tags.FindS("Package");
+      if (Name.empty() == true)
+	 return _error->Error(_("Invalid record in the preferences file, no Package header"));
+      if (Name == "*")
+	 Name = string();
+      
+      const char *Start;
+      const char *End;
+      if (Tags.Find("Pin",Start,End) == false)
+	 continue;
+	 
+      const char *Word = Start;
+      for (; Word != End && isspace(*Word) == 0; Word++);
+
+      // Parse the type..
+      pkgVersionMatch::MatchType Type;
+      if (stringcasecmp(Start,Word,"version") == 0 && Name.empty() == false)
+	 Type = pkgVersionMatch::Version;
+      else if (stringcasecmp(Start,Word,"release") == 0)
+	 Type = pkgVersionMatch::Release;
+      else if (stringcasecmp(Start,Word,"origin") == 0)
+	 Type = pkgVersionMatch::Origin;
+      else
+      {
+	 _error->Warning(_("Did not understand pin type %s"),string(Start,Word).c_str());
+	 continue;
+      }
+      for (; Word != End && isspace(*Word) != 0; Word++);
+
+      Plcy.CreatePin(Type,Name,string(Word,End),
+		     Tags.FindI("Pin-Priority"));
+   }
+
+   Plcy.InitDefaults();
+   return true;
+}
+									/*}}}*/