ENH: Better linker search path computation.

  - Use linker search path -L.. -lfoo for lib w/out soname
    when platform sets CMAKE_PLATFORM_USES_PATH_WHEN_NO_SONAME
  - Rename cmOrderRuntimeDirectories to cmOrderDirectories
    and generalize it for both soname constraints and link
    library constraints
  - Use cmOrderDirectories to order -L directories based
    on all needed constraints
  - Avoid processing implicit link directories
  - For CMAKE_OLD_LINK_PATHS add constraints from libs
    producing them to produce old ordering

1 files changed, 524 insertions, 0 deletions

diff --git a/Source/cmOrderDirectories.cxx b/Source/cmOrderDirectories.cxx
new file mode 100644
index 0000000..7bc5dd6
--- /dev/null
+++ b/Source/cmOrderDirectories.cxx
@@ -0,0 +1,524 @@
+/*=========================================================================
+
+  Program:   CMake - Cross-Platform Makefile Generator
+  Module:    $RCSfile$
+  Language:  C++
+  Date:      $Date$
+  Version:   $Revision$
+
+  Copyright (c) 2002 Kitware, Inc., Insight Consortium.  All rights reserved.
+  See Copyright.txt or http://www.cmake.org/HTML/Copyright.html for details.
+
+     This software is distributed WITHOUT ANY WARRANTY; without even
+     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+     PURPOSE.  See the above copyright notices for more information.
+
+=========================================================================*/
+#include "cmOrderDirectories.h"
+
+#include "cmGlobalGenerator.h"
+#include "cmSystemTools.h"
+
+#include <assert.h>
+
+#include <algorithm>
+
+/*
+Directory ordering computation.
+  - Useful to compute a safe runtime library path order
+  - Need runtime path for supporting INSTALL_RPATH_USE_LINK_PATH
+  - Need runtime path at link time to pickup transitive link dependencies
+    for shared libraries.
+*/
+
+//----------------------------------------------------------------------------
+class cmOrderDirectoriesConstraint
+{
+public:
+  cmOrderDirectoriesConstraint(cmOrderDirectories* od,
+                               std::string const& file):
+    OD(od), GlobalGenerator(od->GlobalGenerator)
+    {
+    this->FullPath = file;
+    this->Directory = cmSystemTools::GetFilenamePath(file);
+    this->FileName = cmSystemTools::GetFilenameName(file);
+    }
+  virtual ~cmOrderDirectoriesConstraint() {}
+
+  void AddDirectory()
+    {
+    this->DirectoryIndex = this->OD->AddOriginalDirectory(this->Directory);
+    }
+
+  virtual void Report(std::ostream& e) = 0;
+
+  void FindConflicts(unsigned int index)
+    {
+    for(unsigned int i=0; i < this->OD->OriginalDirectories.size(); ++i)
+      {
+      // Check if this directory conflicts with they entry.
+      std::string const& dir = this->OD->OriginalDirectories[i];
+      if(dir != this->Directory && this->FindConflict(dir))
+        {
+        // The library will be found in this directory but this is not
+        // the directory named for it.  Add an entry to make sure the
+        // desired directory comes before this one.
+        cmOrderDirectories::ConflictPair p(this->DirectoryIndex, index);
+        this->OD->ConflictGraph[i].push_back(p);
+        }
+      }
+    }
+protected:
+  virtual bool FindConflict(std::string const& dir) = 0;
+
+  bool FileMayConflict(std::string const& dir, std::string const& name);
+
+  cmOrderDirectories* OD;
+  cmGlobalGenerator* GlobalGenerator;
+
+  // The location in which the item is supposed to be found.
+  std::string FullPath;
+  std::string Directory;
+  std::string FileName;
+
+  // The index assigned to the directory.
+  int DirectoryIndex;
+};
+
+//----------------------------------------------------------------------------
+bool cmOrderDirectoriesConstraint::FileMayConflict(std::string const& dir,
+                                                   std::string const& name)
+{
+  // Check if the file will be built by cmake.
+  std::set<cmStdString> const& files =
+    (this->GlobalGenerator->GetDirectoryContent(dir, false));
+  if(std::set<cmStdString>::const_iterator(files.find(name)) != files.end())
+    {
+    return true;
+    }
+
+  // Check if the file exists on disk and is not a symlink back to the
+  // original file.
+  std::string file = dir;
+  file += "/";
+  file += name;
+  if(cmSystemTools::FileExists(file.c_str(), true) &&
+     !cmSystemTools::SameFile(this->FullPath.c_str(), file.c_str()))
+    {
+    return true;
+    }
+  return false;
+}
+
+//----------------------------------------------------------------------------
+class cmOrderDirectoriesConstraintSOName: public cmOrderDirectoriesConstraint
+{
+public:
+  cmOrderDirectoriesConstraintSOName(cmOrderDirectories* od,
+                                     std::string const& file,
+                                     const char* soname):
+    cmOrderDirectoriesConstraint(od, file), SOName(soname? soname : "")
+    {
+    }
+
+  virtual void Report(std::ostream& e)
+    {
+    e << "runtime library [";
+    if(this->SOName.empty())
+      {
+      e << this->FileName;
+      }
+    else
+      {
+      e << this->SOName;
+      }
+    e << "]";
+    }
+
+  virtual bool FindConflict(std::string const& dir);
+private:
+  // The soname of the shared library if it is known.
+  std::string SOName;
+};
+
+//----------------------------------------------------------------------------
+bool cmOrderDirectoriesConstraintSOName::FindConflict(std::string const& dir)
+{
+  // Determine which type of check to do.
+  if(!this->SOName.empty())
+    {
+    // We have the library soname.  Check if it will be found.
+    if(this->FileMayConflict(dir, this->SOName))
+      {
+      return true;
+      }
+    }
+  else
+    {
+    // We do not have the soname.  Look for files in the directory
+    // that may conflict.
+    std::set<cmStdString> const& files =
+      (this->GlobalGenerator
+       ->GetDirectoryContent(dir, true));
+
+    // Get the set of files that might conflict.  Since we do not
+    // know the soname just look at all files that start with the
+    // file name.  Usually the soname starts with the library name.
+    // TODO: Check if the library is a symlink and guess the soname.
+    std::string base = this->FileName;
+    std::set<cmStdString>::const_iterator first = files.lower_bound(base);
+    ++base[base.size()-1];
+    std::set<cmStdString>::const_iterator last = files.upper_bound(base);
+    bool found = false;
+    for(std::set<cmStdString>::const_iterator fi = first; fi != last; ++fi)
+      {
+      return true;
+      }
+    }
+  return false;
+}
+
+//----------------------------------------------------------------------------
+class cmOrderDirectoriesConstraintLibrary: public cmOrderDirectoriesConstraint
+{
+public:
+  cmOrderDirectoriesConstraintLibrary(cmOrderDirectories* od,
+                                      std::string const& file):
+    cmOrderDirectoriesConstraint(od, file)
+    {
+    }
+
+  virtual void Report(std::ostream& e)
+    {
+    e << "link library [" << this->FileName << "]";
+    }
+
+  virtual bool FindConflict(std::string const& dir);
+};
+
+//----------------------------------------------------------------------------
+bool cmOrderDirectoriesConstraintLibrary::FindConflict(std::string const& dir)
+{
+  // We have the library file name.  Check if it will be found.
+  if(this->FileMayConflict(dir, this->FileName))
+    {
+    return true;
+    }
+
+  // Now check if the file exists with other extensions the linker
+  // might consider.
+  if(!this->OD->LinkExtensions.empty() &&
+     this->OD->RemoveLibraryExtension.find(this->FileName))
+    {
+    cmStdString lib = this->OD->RemoveLibraryExtension.match(1);
+    cmStdString ext = this->OD->RemoveLibraryExtension.match(2);
+    for(std::vector<std::string>::iterator
+          i = this->OD->LinkExtensions.begin();
+        i != this->OD->LinkExtensions.end(); ++i)
+      {
+      if(*i != ext)
+        {
+        std::string fname = lib;
+        fname += *i;
+        if(this->FileMayConflict(dir, fname.c_str()))
+          {
+          return true;
+          }
+        }
+      }
+    }
+  return false;
+}
+
+//----------------------------------------------------------------------------
+cmOrderDirectories::cmOrderDirectories(cmGlobalGenerator* gg,
+                                       const char* name,
+                                       const char* purpose)
+{
+  this->GlobalGenerator = gg;
+  this->Name = name;
+  this->Purpose = purpose;
+  this->Computed = false;
+}
+
+//----------------------------------------------------------------------------
+cmOrderDirectories::~cmOrderDirectories()
+{
+  for(std::vector<cmOrderDirectoriesConstraint*>::iterator
+        i = this->ConstraintEntries.begin();
+      i != this->ConstraintEntries.end(); ++i)
+    {
+    delete *i;
+    }
+}
+
+//----------------------------------------------------------------------------
+std::vector<std::string> const& cmOrderDirectories::GetOrderedDirectories()
+{
+  if(!this->Computed)
+    {
+    this->Computed = true;
+    this->CollectOriginalDirectories();
+    this->FindConflicts();
+    this->OrderDirectories();
+    }
+  return this->OrderedDirectories;
+}
+
+//----------------------------------------------------------------------------
+void cmOrderDirectories::AddRuntimeLibrary(std::string const& fullPath,
+                                           const char* soname)
+{
+  // Add the runtime library at most once.
+  if(this->EmmittedConstraintSOName.insert(fullPath).second)
+    {
+    // Avoid dealing with implicit directories.
+    if(!this->ImplicitDirectories.empty())
+      {
+      std::string dir = cmSystemTools::GetFilenamePath(fullPath);
+      if(this->ImplicitDirectories.find(dir) !=
+         this->ImplicitDirectories.end())
+        {
+        return;
+        }
+      }
+
+    // Construct the runtime information entry for this library.
+    this->ConstraintEntries.push_back(
+      new cmOrderDirectoriesConstraintSOName(this, fullPath, soname));
+    }
+  else
+    {
+    // This can happen if the same library is linked multiple times.
+    // In that case the runtime information check need be done only
+    // once anyway.  For shared libs we could add a check in AddItem
+    // to not repeat them.
+    }
+}
+
+//----------------------------------------------------------------------------
+void cmOrderDirectories::AddLinkLibrary(std::string const& fullPath)
+{
+  // Link extension info is required for library constraints.
+  assert(!this->LinkExtensions.empty());
+
+  // Add the link library at most once.
+  if(this->EmmittedConstraintLibrary.insert(fullPath).second)
+    {
+    // Avoid dealing with implicit directories.
+    if(!this->ImplicitDirectories.empty())
+      {
+      std::string dir = cmSystemTools::GetFilenamePath(fullPath);
+      if(this->ImplicitDirectories.find(dir) !=
+         this->ImplicitDirectories.end())
+        {
+        return;
+        }
+      }
+
+    // Construct the link library entry.
+    this->ConstraintEntries.push_back(
+      new cmOrderDirectoriesConstraintLibrary(this, fullPath));
+    }
+}
+
+//----------------------------------------------------------------------------
+void
+cmOrderDirectories
+::AddUserDirectories(std::vector<std::string> const& extra)
+{
+  this->UserDirectories.insert(this->UserDirectories.end(),
+                               extra.begin(), extra.end());
+}
+
+//----------------------------------------------------------------------------
+void
+cmOrderDirectories
+::SetImplicitDirectories(std::set<cmStdString> const& implicitDirs)
+{
+  this->ImplicitDirectories = implicitDirs;
+}
+
+//----------------------------------------------------------------------------
+void
+cmOrderDirectories
+::SetLinkExtensionInfo(std::vector<std::string> const& linkExtensions,
+                       std::string const& removeExtRegex)
+{
+  this->LinkExtensions = linkExtensions;
+  this->RemoveLibraryExtension.compile(removeExtRegex.c_str());
+}
+
+//----------------------------------------------------------------------------
+void cmOrderDirectories::CollectOriginalDirectories()
+{
+  // Add user directories specified for inclusion.  These should be
+  // indexed first so their original order is preserved as much as
+  // possible subject to the constraints.
+  for(std::vector<std::string>::const_iterator
+        di = this->UserDirectories.begin();
+      di != this->UserDirectories.end(); ++di)
+    {
+    // Avoid dealing with implicit directories.
+    if(this->ImplicitDirectories.find(*di) !=
+       this->ImplicitDirectories.end())
+      {
+      continue;
+      }
+
+    // Skip the empty string.
+    if(di->empty())
+      {
+      continue;
+      }
+
+    // Add this directory.
+    this->AddOriginalDirectory(*di);
+    }
+
+  // Add directories containing constraints.
+  for(unsigned int i=0; i < this->ConstraintEntries.size(); ++i)
+    {
+    this->ConstraintEntries[i]->AddDirectory();
+    }
+}
+
+//----------------------------------------------------------------------------
+int cmOrderDirectories::AddOriginalDirectory(std::string const& dir)
+{
+  // Add the runtime directory with a unique index.
+  std::map<cmStdString, int>::iterator i =
+    this->DirectoryIndex.find(dir);
+  if(i == this->DirectoryIndex.end())
+    {
+    std::map<cmStdString, int>::value_type
+      entry(dir, static_cast<int>(this->OriginalDirectories.size()));
+    i = this->DirectoryIndex.insert(entry).first;
+    this->OriginalDirectories.push_back(dir);
+    }
+
+  return i->second;
+}
+
+//----------------------------------------------------------------------------
+struct cmOrderDirectoriesCompare
+{
+  typedef std::pair<int, int> ConflictPair;
+
+  // The conflict pair is unique based on just the directory
+  // (first).  The second element is only used for displaying
+  // information about why the entry is present.
+  bool operator()(ConflictPair const& l,
+                  ConflictPair const& r)
+    {
+    return l.first == r.first;
+    }
+};
+
+//----------------------------------------------------------------------------
+void cmOrderDirectories::FindConflicts()
+{
+  // Allocate the conflict graph.
+  this->ConflictGraph.resize(this->OriginalDirectories.size());
+  this->DirectoryVisited.resize(this->OriginalDirectories.size(), 0);
+
+  // Find directories conflicting with each entry.
+  for(unsigned int i=0; i < this->ConstraintEntries.size(); ++i)
+    {
+    this->ConstraintEntries[i]->FindConflicts(i);
+    }
+
+  // Clean up the conflict graph representation.
+  for(std::vector<ConflictList>::iterator
+        i = this->ConflictGraph.begin();
+      i != this->ConflictGraph.end(); ++i)
+    {
+    // Sort the outgoing edges for each graph node so that the
+    // original order will be preserved as much as possible.
+    std::sort(i->begin(), i->end());
+
+    // Make the edge list unique so cycle detection will be reliable.
+    ConflictList::iterator last =
+      std::unique(i->begin(), i->end(), cmOrderDirectoriesCompare());
+    i->erase(last, i->end());
+    }
+}
+
+//----------------------------------------------------------------------------
+void cmOrderDirectories::OrderDirectories()
+{
+  // Allow a cycle to be diagnosed once.
+  this->CycleDiagnosed = false;
+  this->WalkId = 0;
+
+  // Iterate through the directories in the original order.
+  for(unsigned int i=0; i < this->OriginalDirectories.size(); ++i)
+    {
+    // Start a new DFS from this node.
+    ++this->WalkId;
+    this->VisitDirectory(i);
+    }
+}
+
+//----------------------------------------------------------------------------
+void cmOrderDirectories::VisitDirectory(unsigned int i)
+{
+  // Skip nodes already visited.
+  if(this->DirectoryVisited[i])
+    {
+    if(this->DirectoryVisited[i] == this->WalkId)
+      {
+      // We have reached a node previously visited on this DFS.
+      // There is a cycle.
+      this->DiagnoseCycle();
+      }
+    return;
+    }
+
+  // We are now visiting this node so mark it.
+  this->DirectoryVisited[i] = this->WalkId;
+
+  // Visit the neighbors of the node first.
+  ConflictList const& clist = this->ConflictGraph[i];
+  for(ConflictList::const_iterator j = clist.begin();
+      j != clist.end(); ++j)
+    {
+    this->VisitDirectory(j->first);
+    }
+
+  // Now that all directories required to come before this one have
+  // been emmitted, emit this directory.
+  this->OrderedDirectories.push_back(this->OriginalDirectories[i]);
+}
+
+//----------------------------------------------------------------------------
+void cmOrderDirectories::DiagnoseCycle()
+{
+  // Report the cycle at most once.
+  if(this->CycleDiagnosed)
+    {
+    return;
+    }
+  this->CycleDiagnosed = true;
+
+  // Construct the message.
+  cmOStringStream e;
+  e << "WARNING: Cannot generate a safe " << this->Purpose
+    << " for target " << this->Name
+    << " because there is a cycle in the constraint graph:\n";
+
+  // Display the conflict graph.
+  for(unsigned int i=0; i < this->ConflictGraph.size(); ++i)
+    {
+    ConflictList const& clist = this->ConflictGraph[i];
+    e << "dir " << i << " is [" << this->OriginalDirectories[i] << "]\n";
+    for(ConflictList::const_iterator j = clist.begin();
+        j != clist.end(); ++j)
+      {
+      e << "  dir " << j->first << " must precede it due to ";
+      this->ConstraintEntries[j->second]->Report(e);
+      e << "\n";
+      }
+    }
+  cmSystemTools::Message(e.str().c_str());
+}