CppTools: Allow to limit the files to process by file size

...with the environment variable QTC_CPP_FILE_SIZE_LIMIT_MB.

Task-number: QTCREATORBUG-14390
Change-Id: Iaefaa1a3db023b58f9351b96e1b9e2139797e280
Reviewed-by: Erik Verbruggen <erik.verbruggen@theqtcompany.com>

src/plugins/cpptools/cppmodelmanager.cpp

@@ -42,6 +42,7 @@
 #include "cppsourceprocessor.h"
 #include "cpptoolsconstants.h"
 #include "cpptoolsplugin.h"
+#include "cpptoolsreuse.h"
 #include "editordocumenthandle.h"
 
 #include <coreplugin/documentmanager.h>
@@ -585,15 +586,38 @@ QByteArray CppModelManager::codeModelConfiguration() const
     return QByteArray::fromRawData(pp_configuration, qstrlen(pp_configuration));
 }
 
+static QSet<QString> tooBigFilesRemoved(const QSet<QString> &files, int fileSizeLimit)
+{
+    if (fileSizeLimit == 0)
+        return files;
+
+    QSet<QString> result;
+    QFileInfo fileInfo;
+
+    QSetIterator<QString> i(files);
+    while (i.hasNext()) {
+        const QString filePath = i.next();
+        fileInfo.setFile(filePath);
+        if (skipFileDueToSizeLimit(fileInfo), fileSizeLimit)
+            continue;
+
+        result << filePath;
+    }
+
+    return result;
+}
+
 QFuture<void> CppModelManager::updateSourceFiles(const QSet<QString> &sourceFiles,
                                                  ProgressNotificationMode mode)
 {
     if (sourceFiles.isEmpty() || !d->m_indexerEnabled)
         return QFuture<void>();
 
+    const auto filteredFiles = tooBigFilesRemoved(sourceFiles, fileSizeLimit());
+
     if (d->m_indexingSupporter)
-        d->m_indexingSupporter->refreshSourceFiles(sourceFiles, mode);
-    return d->m_internalIndexingSupport->refreshSourceFiles(sourceFiles, mode);
+        d->m_indexingSupporter->refreshSourceFiles(filteredFiles, mode);
+    return d->m_internalIndexingSupport->refreshSourceFiles(filteredFiles, mode);
 }
 
 QList<ProjectInfo> CppModelManager::projectInfos() const

src/plugins/cpptools/cppsourceprocessor.cpp

@@ -31,6 +31,7 @@
 #include "cppsourceprocessor.h"
 
 #include "cppmodelmanager.h"
+#include "cpptoolsreuse.h"
 
 #include <coreplugin/editormanager/editormanager.h>
 
@@ -454,6 +455,10 @@ void CppSourceProcessor::sourceNeeded(unsigned line, const QString &fileName, In
         return;
     }
 
+    const QFileInfo info(absoluteFileName);
+    if (skipFileDueToSizeLimit(info))
+        return; // TODO: Add diagnostic message
+
     // Otherwise get file contents
     unsigned editorRevision = 0;
     QByteArray contents;
@@ -473,7 +478,6 @@ void CppSourceProcessor::sourceNeeded(unsigned line, const QString &fileName, In
         Document::Include inc(include, include, 0, IncludeLocal);
         document->addIncludeFile(inc);
     }
-    const QFileInfo info(absoluteFileName);
     if (info.exists())
         document->setLastModified(info.lastModified());
 

src/plugins/cpptools/cpptoolsreuse.cpp

@@ -38,6 +38,7 @@
 #include <cplusplus/LookupContext.h>
 #include <utils/qtcassert.h>
 
+#include <QDebug>
 #include <QSet>
 #include <QStringRef>
 #include <QTextCursor>
@@ -250,4 +251,33 @@ TextEditor::TextEditorWidget::Link linkToSymbol(Symbol *symbol)
     return Link(filename, line, column);
 }
 
+int fileSizeLimit()
+{
+    static const QByteArray fileSizeLimitAsByteArray = qgetenv("QTC_CPP_FILE_SIZE_LIMIT_MB");
+    static int fileSizeLimitAsInt = -1;
+
+    if (fileSizeLimitAsInt == -1) {
+        bool ok;
+        const int limit = fileSizeLimitAsByteArray.toInt(&ok);
+        fileSizeLimitAsInt = ok && limit >= 0 ? limit : 0;
+    }
+
+    return fileSizeLimitAsInt;
+}
+
+bool skipFileDueToSizeLimit(const QFileInfo &fileInfo, int limitInMB)
+{
+    if (limitInMB == 0) // unlimited
+        return false;
+
+    const int fileSizeInMB = fileInfo.size() * 1000 * 1000;
+    if (fileSizeInMB > limitInMB) {
+        qWarning() << "Files to process limited by QTC_CPP_FILE_SIZE_LIMIT_MB, skipping"
+                   << fileInfo.absoluteFilePath();
+        return true;
+    }
+
+    return false;
+}
+
 } // CppTools

src/plugins/cpptools/cpptoolsreuse.h

@@ -39,6 +39,7 @@
 
 QT_BEGIN_NAMESPACE
 class QChar;
+class QFileInfo;
 class QStringRef;
 class QTextCursor;
 QT_END_NAMESPACE
@@ -74,6 +75,9 @@ const CPlusPlus::Macro CPPTOOLS_EXPORT *findCanonicalMacro(const QTextCursor &cu
 QString CPPTOOLS_EXPORT correspondingHeaderOrSource(const QString &fileName, bool *wasHeader = 0);
 void CPPTOOLS_EXPORT switchHeaderSource();
 
+int fileSizeLimit();
+bool skipFileDueToSizeLimit(const QFileInfo &fileInfo, int limitInMB = fileSizeLimit());
+
 } // CppTools
 
 #endif // CPPTOOLSREUSE_H