export: Implement EXPORT subcommand (#9822)

Teach the export command to handle export sets defined by invocations
of install(TARGETS ... EXPORT foo).  This makes maintenance of targets
exported to both the build tree and install tree trivial.

1 files changed, 107 insertions, 53 deletions

diff --git a/Source/cmExportCommand.cxx b/Source/cmExportCommand.cxx
index 0a67ccf..b6bf870 100644
--- a/Source/cmExportCommand.cxx
+++ b/Source/cmExportCommand.cxx
@@ -30,14 +30,12 @@ cmExportCommand::cmExportCommand()
 ,ArgumentGroup()
 ,Targets(&Helper, "TARGETS")
 ,Append(&Helper, "APPEND", &ArgumentGroup)
+,ExportSetName(&Helper, "EXPORT", &ArgumentGroup)
 ,Namespace(&Helper, "NAMESPACE", &ArgumentGroup)
 ,Filename(&Helper, "FILE", &ArgumentGroup)
 ,ExportOld(&Helper, "EXPORT_LINK_INTERFACE_LIBRARIES", &ArgumentGroup)
 {
-  // at first TARGETS
-  this->Targets.Follows(0);
-  // and after that the other options in any order
-  this->ArgumentGroup.Follows(&this->Targets);
+  this->ExportSet = 0;
 }
 
 
@@ -55,6 +53,16 @@ bool cmExportCommand
     {
     return this->HandlePackage(args);
     }
+  else if (args[0] == "EXPORT")
+    {
+    this->ExportSetName.Follows(0);
+    this->ArgumentGroup.Follows(&this->ExportSetName);
+    }
+  else
+    {
+    this->Targets.Follows(0);
+    this->ArgumentGroup.Follows(&this->Targets);
+    }
 
   std::vector<std::string> unknownArgs;
   this->Helper.Parse(&args, &unknownArgs);
@@ -65,31 +73,32 @@ bool cmExportCommand
     return false;
     }
 
-  if (this->Targets.WasFound() == false)
-    {
-    this->SetError("TARGETS option missing.");
-    return false;
-    }
-
+  std::string fname;
   if(!this->Filename.WasFound())
     {
-    this->SetError("FILE <filename> option missing.");
-    return false;
+    if (args[0] != "EXPORT")
+      {
+      this->SetError("FILE <filename> option missing.");
+      return false;
+      }
+    fname = this->ExportSetName.GetString() + ".cmake";
     }
-
-  // Make sure the file has a .cmake extension.
-  if(cmSystemTools::GetFilenameLastExtension(this->Filename.GetCString())
-     != ".cmake")
+  else
     {
-    cmOStringStream e;
-    e << "FILE option given filename \"" << this->Filename.GetString()
-      << "\" which does not have an extension of \".cmake\".\n";
-    this->SetError(e.str().c_str());
-    return false;
+    // Make sure the file has a .cmake extension.
+    if(cmSystemTools::GetFilenameLastExtension(this->Filename.GetCString())
+      != ".cmake")
+      {
+      cmOStringStream e;
+      e << "FILE option given filename \"" << this->Filename.GetString()
+        << "\" which does not have an extension of \".cmake\".\n";
+      this->SetError(e.str().c_str());
+      return false;
+      }
+    fname = this->Filename.GetString();
     }
 
   // Get the file to write.
-  std::string fname = this->Filename.GetString();
   if(cmSystemTools::FileIsFullPath(fname.c_str()))
     {
     if(!this->Makefile->CanIWriteThisFile(fname.c_str()))
@@ -104,57 +113,95 @@ bool cmExportCommand
   else
     {
     // Interpret relative paths with respect to the current build dir.
-    fname = this->Makefile->GetCurrentOutputDirectory();
-    fname += "/";
-    fname += this->Filename.GetString();
+    std::string dir = this->Makefile->GetCurrentOutputDirectory();
+    fname = dir + "/" + fname;
     }
 
-  for(std::vector<std::string>::const_iterator
-      currentTarget = this->Targets.GetVector().begin();
-      currentTarget != this->Targets.GetVector().end();
-      ++currentTarget)
+  std::vector<std::string> targets;
+
+  cmGlobalGenerator *gg = this->Makefile->GetLocalGenerator()
+                                        ->GetGlobalGenerator();
+
+  if(args[0] == "EXPORT")
     {
-    if (this->Makefile->IsAlias(currentTarget->c_str()))
+    if (this->Append.IsEnabled())
+      {
+      cmOStringStream e;
+      e << "EXPORT signature does not recognise the APPEND option.";
+      this->SetError(e.str().c_str());
+      return false;
+      }
+
+    if (this->ExportOld.IsEnabled())
       {
       cmOStringStream e;
-      e << "given ALIAS target \"" << *currentTarget
-        << "\" which may not be exported.";
+      e << "EXPORT signature does not recognise the "
+        "EXPORT_LINK_INTERFACE_LIBRARIES option.";
       this->SetError(e.str().c_str());
       return false;
       }
 
-    if(cmTarget* target =
-       this->Makefile->GetLocalGenerator()->
-       GetGlobalGenerator()->FindTarget(0, currentTarget->c_str()))
+    cmExportSetMap &setMap = gg->GetExportSets();
+    std::string setName = this->ExportSetName.GetString();
+    if (setMap.find(setName) == setMap.end())
       {
-      if(target->GetType() == cmTarget::OBJECT_LIBRARY)
+      cmOStringStream e;
+      e << "Export set \"" << setName << "\" not found.";
+      this->SetError(e.str().c_str());
+      return false;
+      }
+    this->ExportSet = setMap[setName];
+    }
+  else if (this->Targets.WasFound())
+    {
+    for(std::vector<std::string>::const_iterator
+        currentTarget = this->Targets.GetVector().begin();
+        currentTarget != this->Targets.GetVector().end();
+        ++currentTarget)
+      {
+      if (this->Makefile->IsAlias(currentTarget->c_str()))
         {
         cmOStringStream e;
-        e << "given OBJECT library \"" << *currentTarget
+        e << "given ALIAS target \"" << *currentTarget
           << "\" which may not be exported.";
         this->SetError(e.str().c_str());
         return false;
         }
+
+      if(cmTarget* target = gg->FindTarget(0, currentTarget->c_str()))
+        {
+        if(target->GetType() == cmTarget::OBJECT_LIBRARY)
+          {
+          cmOStringStream e;
+          e << "given OBJECT library \"" << *currentTarget
+            << "\" which may not be exported.";
+          this->SetError(e.str().c_str());
+          return false;
+          }
+        }
+      else
+        {
+        cmOStringStream e;
+        e << "given target \"" << *currentTarget
+          << "\" which is not built by this project.";
+        this->SetError(e.str().c_str());
+        return false;
+        }
+      targets.push_back(*currentTarget);
       }
-    else
+    if (this->Append.IsEnabled())
       {
-      cmOStringStream e;
-      e << "given target \"" << *currentTarget
-        << "\" which is not built by this project.";
-      this->SetError(e.str().c_str());
-      return false;
+      if (cmExportBuildFileGenerator *ebfg = gg->GetExportedTargetsFile(fname))
+        {
+        ebfg->AppendTargets(targets);
+        return true;
+        }
       }
     }
-
-  cmGlobalGenerator *gg = this->Makefile->GetLocalGenerator()
-                                        ->GetGlobalGenerator();
-  if (this->Append.IsEnabled())
+  else
     {
-    if (cmExportBuildFileGenerator *ebfg = gg->GetExportedTargetsFile(fname))
-      {
-      ebfg->AppendTargets(this->Targets.GetVector());
-      return true;
-      }
+    this->SetError("EXPORT or TARGETS specifier missing.");
+    return false;
     }
 
   // Setup export file generation.
@@ -162,7 +209,14 @@ bool cmExportCommand
   ebfg->SetExportFile(fname.c_str());
   ebfg->SetNamespace(this->Namespace.GetCString());
   ebfg->SetAppendMode(this->Append.IsEnabled());
-  ebfg->SetTargets(this->Targets.GetVector());
+  if (this->ExportSet)
+    {
+    ebfg->SetExportSet(this->ExportSet);
+    }
+  else
+    {
+    ebfg->SetTargets(targets);
+    }
   ebfg->SetMakefile(this->Makefile);
   ebfg->SetExportOld(this->ExportOld.IsEnabled());