1 files changed, 143 insertions, 0 deletions
diff --git a/Source/cmWhileCommand.cxx b/Source/cmWhileCommand.cxx
new file mode 100644
index 0000000..26e7c75
--- /dev/null
+++ b/Source/cmWhileCommand.cxx
@@ -0,0 +1,143 @@
+/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+   file Copyright.txt or https://cmake.org/licensing for details.  */
+#include "cmWhileCommand.h"
+
+#include <string>
+#include <utility>
+
+#include <cm/memory>
+#include <cm/string_view>
+
+#include "cm_static_string_view.hxx"
+
+#include "cmConditionEvaluator.h"
+#include "cmExecutionStatus.h"
+#include "cmExpandedCommandArgument.h"
+#include "cmFunctionBlocker.h"
+#include "cmListFileCache.h"
+#include "cmMakefile.h"
+#include "cmMessageType.h"
+#include "cmSystemTools.h"
+
+class cmWhileFunctionBlocker : public cmFunctionBlocker
+{
+public:
+  cmWhileFunctionBlocker(cmMakefile* mf);
+  ~cmWhileFunctionBlocker() override;
+
+  cm::string_view StartCommandName() const override { return "while"_s; }
+  cm::string_view EndCommandName() const override { return "endwhile"_s; }
+
+  bool ArgumentsMatch(cmListFileFunction const& lff,
+                      cmMakefile& mf) const override;
+
+  bool Replay(std::vector<cmListFileFunction> functions,
+              cmExecutionStatus& inStatus) override;
+
+  std::vector<cmListFileArgument> Args;
+
+private:
+  cmMakefile* Makefile;
+};
+
+cmWhileFunctionBlocker::cmWhileFunctionBlocker(cmMakefile* mf)
+  : Makefile(mf)
+{
+  this->Makefile->PushLoopBlock();
+}
+
+cmWhileFunctionBlocker::~cmWhileFunctionBlocker()
+{
+  this->Makefile->PopLoopBlock();
+}
+
+bool cmWhileFunctionBlocker::ArgumentsMatch(cmListFileFunction const& lff,
+                                            cmMakefile&) const
+{
+  return lff.Arguments.empty() || lff.Arguments == this->Args;
+}
+
+bool cmWhileFunctionBlocker::Replay(std::vector<cmListFileFunction> functions,
+                                    cmExecutionStatus& inStatus)
+{
+  cmMakefile& mf = inStatus.GetMakefile();
+  std::string errorString;
+
+  std::vector<cmExpandedCommandArgument> expandedArguments;
+  mf.ExpandArguments(this->Args, expandedArguments);
+  MessageType messageType;
+
+  cmListFileContext execContext = this->GetStartingContext();
+
+  cmCommandContext commandContext;
+  commandContext.Line = execContext.Line;
+  commandContext.Name = execContext.Name;
+
+  cmConditionEvaluator conditionEvaluator(mf, this->GetStartingContext(),
+                                          mf.GetBacktrace(commandContext));
+
+  bool isTrue =
+    conditionEvaluator.IsTrue(expandedArguments, errorString, messageType);
+
+  while (isTrue) {
+    if (!errorString.empty()) {
+      std::string err = "had incorrect arguments: ";
+      for (cmListFileArgument const& arg : this->Args) {
+        err += (arg.Delim ? "\"" : "");
+        err += arg.Value;
+        err += (arg.Delim ? "\"" : "");
+        err += " ";
+      }
+      err += "(";
+      err += errorString;
+      err += ").";
+      mf.IssueMessage(messageType, err);
+      if (messageType == MessageType::FATAL_ERROR) {
+        cmSystemTools::SetFatalErrorOccured();
+        return true;
+      }
+    }
+
+    // Invoke all the functions that were collected in the block.
+    for (cmListFileFunction const& fn : functions) {
+      cmExecutionStatus status(mf);
+      mf.ExecuteCommand(fn, status);
+      if (status.GetReturnInvoked()) {
+        inStatus.SetReturnInvoked();
+        return true;
+      }
+      if (status.GetBreakInvoked()) {
+        return true;
+      }
+      if (status.GetContinueInvoked()) {
+        break;
+      }
+      if (cmSystemTools::GetFatalErrorOccured()) {
+        return true;
+      }
+    }
+    expandedArguments.clear();
+    mf.ExpandArguments(this->Args, expandedArguments);
+    isTrue =
+      conditionEvaluator.IsTrue(expandedArguments, errorString, messageType);
+  }
+  return true;
+}
+
+bool cmWhileCommand(std::vector<cmListFileArgument> const& args,
+                    cmExecutionStatus& status)
+{
+  if (args.empty()) {
+    status.SetError("called with incorrect number of arguments");
+    return false;
+  }
+
+  // create a function blocker
+  {
+    cmMakefile& makefile = status.GetMakefile();
+    auto fb = cm::make_unique<cmWhileFunctionBlocker>(&makefile);
+    fb->Args = args;
+    makefile.AddFunctionBlocker(std::move(fb));
+  }
+  return true;
+}