CxxIssuesReportSensor: use realPath as part of path normalization

resolves #1651 (?)

cxx-sensors/src/main/java/org/sonar/cxx/sensors/utils/CxxIssuesReportSensor.java

@@ -20,13 +20,18 @@
 package org.sonar.cxx.sensors.utils;
 
 import java.io.File;
+import java.io.IOException;
+import java.nio.file.LinkOption;
+import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import javax.annotation.Nullable;
+
+import org.sonar.api.batch.fs.FilePredicate;
 import org.sonar.api.batch.fs.InputFile;
 import org.sonar.api.batch.sensor.SensorContext;
 import org.sonar.api.batch.sensor.issue.NewIssue;
@@ -139,8 +144,25 @@ public InputFile getInputFileIfInProject(SensorContext sensorContext, String pat
     if (notFoundFiles.contains(path)) {
       return null;
     }
-    final InputFile inputFile = sensorContext.fileSystem().inputFile(sensorContext.
-      fileSystem().predicates().hasPath(path));
+
+    final Path absolutePath = sensorContext.fileSystem().baseDir().toPath().resolve(path);
+    FilePredicate searchPredicate;
+    try {
+      // normalize path by means of Path::toRealPath in order to please the
+      // case-insensitive file systems. Don't follow symbolic links, because we
+      // might end-up in the location outside of the module's base directory...
+      final Path realPath = absolutePath.toRealPath(LinkOption.NOFOLLOW_LINKS);
+      searchPredicate = sensorContext.fileSystem().predicates().hasAbsolutePath(realPath.toString());
+    } catch (IOException e) {
+      // ...if impossible - fallback to the most generic search predicate
+      if (LOG.isDebugEnabled()) {
+        LOG.debug("Unable to get the real path: module {}, baseDir {}, path {}", sensorContext.module().key(),
+            sensorContext.fileSystem().baseDir(), path);
+      }
+      searchPredicate = sensorContext.fileSystem().predicates().hasPath(path);
+    }
+
+    final InputFile inputFile = sensorContext.fileSystem().inputFile(searchPredicate);
     if (inputFile == null) {
       LOG.warn("Cannot find the file '{}' in module '{}' base dir '{}', skipping violations.",
         path, sensorContext.module().key(), sensorContext.fileSystem().baseDir());