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-rw-r--r--compilerplugins/clang/constfieldsrewrite.cxx169
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diff --git a/compilerplugins/clang/constfieldsrewrite.cxx b/compilerplugins/clang/constfieldsrewrite.cxx
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+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#if !defined _WIN32 //TODO, #include <sys/mman.h>
+
+#include <cassert>
+#include <string>
+#include <iostream>
+#include "plugin.hxx"
+#include "check.hxx"
+#include "config_clang.h"
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <assert.h>
+#include <cstring>
+
+/**
+ This is intended to be run as the second stage of the "constfields" clang plugin.
+*/
+
+namespace
+{
+class ConstFieldsRewrite : public RecursiveASTVisitor<ConstFieldsRewrite>,
+ public loplugin::RewritePlugin
+{
+public:
+ explicit ConstFieldsRewrite(loplugin::InstantiationData const& data);
+ ~ConstFieldsRewrite();
+
+ virtual void run() override
+ {
+ if (rewriter)
+ {
+ TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
+ }
+ }
+
+ bool VisitFieldDecl(const FieldDecl* var);
+
+private:
+ // I use a brute-force approach - mmap the results file and do a linear search on it
+ // It works surprisingly well, because the file is small enough to fit into L2 cache on modern CPU's
+ size_t mmapFilesize;
+ int mmapFD;
+ char* mmappedData;
+};
+
+size_t getFilesize(const char* filename)
+{
+ struct stat st;
+ stat(filename, &st);
+ return st.st_size;
+}
+
+ConstFieldsRewrite::ConstFieldsRewrite(loplugin::InstantiationData const& data)
+ : RewritePlugin(data)
+{
+ static const char sInputFile[] = SRCDIR "/compilerplugins/clang/constfields.results";
+ mmapFilesize = getFilesize(sInputFile);
+ //Open file
+ mmapFD = open(sInputFile, O_RDONLY, 0);
+ assert(mmapFD != -1);
+ //Execute mmap
+ mmappedData = static_cast<char*>(mmap(NULL, mmapFilesize, PROT_READ, MAP_PRIVATE, mmapFD, 0));
+ assert(mmappedData != NULL);
+}
+
+ConstFieldsRewrite::~ConstFieldsRewrite()
+{
+ //Cleanup
+ int rc = munmap(mmappedData, mmapFilesize);
+ assert(rc == 0);
+ (void)rc;
+ close(mmapFD);
+}
+
+bool ConstFieldsRewrite::VisitFieldDecl(const FieldDecl* fieldDecl)
+{
+ if (ignoreLocation(fieldDecl))
+ return true;
+ // ignore stuff that forms part of the stable URE interface
+ if (isInUnoIncludeFile(compiler.getSourceManager().getSpellingLoc(
+ fieldDecl->getCanonicalDecl()->getLocation())))
+ return true;
+ // in case we've already processed this field
+ if (fieldDecl->getType().isConstQualified())
+ return true;
+ // TODO rewriting T& is a bit trickier
+ if (loplugin::TypeCheck(fieldDecl->getType()).LvalueReference())
+ return true;
+
+ const RecordDecl* recordDecl = fieldDecl->getParent();
+ std::string parentClassName;
+ if (const CXXRecordDecl* cxxRecordDecl = dyn_cast<CXXRecordDecl>(recordDecl))
+ {
+ if (cxxRecordDecl->getTemplateInstantiationPattern())
+ cxxRecordDecl = cxxRecordDecl->getTemplateInstantiationPattern();
+ parentClassName = cxxRecordDecl->getQualifiedNameAsString();
+ }
+ else
+ {
+ parentClassName = recordDecl->getQualifiedNameAsString();
+ }
+ // the extra spaces match the formatting in the results file, and help avoid false+
+ std::string aNiceName = " " + parentClassName + " " + fieldDecl->getNameAsString() + " "
+ + fieldDecl->getType().getAsString() + "\n";
+
+ // search mmap'ed file for field
+ const char* aNiceNameStr = aNiceName.c_str();
+ char* found = std::search(mmappedData, mmappedData + mmapFilesize, aNiceNameStr,
+ aNiceNameStr + aNiceName.size());
+ if (!(found < mmappedData + mmapFilesize))
+ return true;
+
+ SourceManager& SM = compiler.getSourceManager();
+ auto endLoc = fieldDecl->getTypeSourceInfo()->getTypeLoc().getEndLoc();
+ endLoc = endLoc.getLocWithOffset(Lexer::MeasureTokenLength(endLoc, SM, compiler.getLangOpts()));
+
+ // Calculate how much space is available after the type declaration that we can use to
+ // overwrite with the " const". This reduces the amount of formatting fixups I need to do.
+ char const* p1 = SM.getCharacterData(endLoc);
+ bool success = false;
+ if (*p1 != ' ')
+ {
+ // Sometimes there is no space at all e.g. in
+ // FastTokenHandlerBase *mpTokenHandler;
+ // between the "*" and the "mpTokenHandler", so add an extra space.
+ success = insertText(endLoc, " const ");
+ }
+ else
+ {
+ int spaceAvailable = 1;
+ ++p1;
+ for (; spaceAvailable < 6; ++spaceAvailable)
+ {
+ if (*p1 != ' ')
+ break;
+ ++p1;
+ }
+ if (spaceAvailable < 6)
+ success = replaceText(endLoc, spaceAvailable - 1, " const");
+ else
+ success = replaceText(endLoc, spaceAvailable, " const");
+ }
+
+ if (!success)
+ {
+ report(DiagnosticsEngine::Warning, "Could not mark field as const",
+ fieldDecl->getBeginLoc())
+ << fieldDecl->getSourceRange();
+ }
+ return true;
+}
+
+loplugin::Plugin::Registration<ConstFieldsRewrite> X("constfieldsrewrite", false);
+}
+
+#endif
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */