qdoc: Don't load index in -prepare phase

qdoc was loading index files during the -prepare
phase, which it shouldn't do. The index files it
was loading were from modules other than the one
qdoc was running on. They had not been deleted
because qdoc only clears the output directory of
the module it is running on.

Also added a static function to the Location class
to print information messages on standard error.
This is useful to see what qdoc is doing and when
it is doing it because these log messages are
interleaved in the qdoc error messages. More of
these log messages will be added as needed.

Also removed some unneeded qDebug() stuff in
the code that processes the dependencies from
the qdocconf file.

Task number: QTBUG-27707

Change-Id: I1eec8d6ec89ff040969c2a1f62f21f551f347e05
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@digia.com>

4 files changed, 122 insertions, 92 deletions

diff --git a/src/tools/qdoc/location.cpp b/src/tools/qdoc/location.cpp
index 8964633125..48e5d6153c 100644
--- a/src/tools/qdoc/location.cpp
+++ b/src/tools/qdoc/location.cpp
@@ -336,6 +336,15 @@ void Location::information(const QString& message)
 }
 
 /*!
+  Prints \a message to \c stderr followed by a \c{'\n'}.
+ */
+void Location::logToStdErr(const QString& message)
+{
+    fprintf(stderr, "%s\n", message.toLatin1().data());
+    fflush(stderr);
+}
+
+/*!
   Report a program bug, including the \a hint.
  */
 void Location::internalError(const QString& hint)
diff --git a/src/tools/qdoc/location.h b/src/tools/qdoc/location.h
index d2c9487968..71492e619f 100644
--- a/src/tools/qdoc/location.h
+++ b/src/tools/qdoc/location.h
@@ -96,6 +96,7 @@ public:
     static void terminate();
     static void information(const QString& message);
     static void internalError(const QString& hint);
+    static void logToStdErr(const QString& message);
 
 private:
     enum MessageType { Warning, Error };
diff --git a/src/tools/qdoc/main.cpp b/src/tools/qdoc/main.cpp
index 5fbc01f1f0..d46580bbea 100644
--- a/src/tools/qdoc/main.cpp
+++ b/src/tools/qdoc/main.cpp
@@ -101,6 +101,9 @@ static bool obsoleteLinks = false;
 static QStringList defines;
 static QStringList dependModules;
 static QStringList indexDirs;
+static QString currentDir;
+static QString prevCurrentDir;
+static QString documentationPath;
 
 /*!
   Print the help message to \c stdout.
@@ -118,7 +121,7 @@ static void printHelp()
                              "    -highlighting  "
                              "Turn on syntax highlighting (makes qdoc run slower)\n"
                              "    -indexdir      "
-                             "Specify a directory where QDoc should search for indices to link to\n"
+                             "Specify a directory where QDoc should search for index files to load\n"
                              "    -installdir    "
                              "Specify the directory where the output will be after running \"make install\"\n"
                              "    -no-examples   "
@@ -150,6 +153,88 @@ static void printVersion()
     Location::information(s);
 }
 
+static void loadIndexFiles(Config& config)
+{
+    QDocDatabase* qdb = QDocDatabase::qdocDB();
+    /*
+      Read some XML indexes containing definitions from other documentation sets.
+     */
+    QStringList indexFiles = config.getStringList(CONFIG_INDEXES);
+
+    dependModules += config.getStringList(CONFIG_DEPENDS);
+
+    // Allow modules and third-party application/libraries to link
+    // to the Qt docs without having to explicitly pass --indexdir.
+    if (!indexDirs.contains(documentationPath))
+        indexDirs.append(documentationPath);
+
+    if (dependModules.size() > 0) {
+        if (indexDirs.size() > 0) {
+            for (int i = 0; i < indexDirs.size(); i++) {
+                if (indexDirs[i].startsWith("..")) {
+                    const QString prefix(QDir(currentDir).relativeFilePath(prevCurrentDir));
+                    if (!prefix.isEmpty())
+                        indexDirs[i].prepend(prefix + QLatin1Char('/'));
+                }
+            }
+            /*
+              Add all subdirectories of the indexdirs as dependModules,
+              when an asterisk is used in the 'depends' list.
+            */
+            if (dependModules.contains("*")) {
+                dependModules.removeOne("*");
+                for (int i = 0; i < indexDirs.size(); i++) {
+                    QDir scanDir = QDir(indexDirs[i]);
+                    scanDir.setFilter(QDir::Dirs | QDir::NoDotAndDotDot);
+                    QFileInfoList dirList = scanDir.entryInfoList();
+                    for (int j = 0; j < dirList.size(); j++) {
+                        if (dirList[j].fileName().toLower() != config.getString(CONFIG_PROJECT).toLower())
+                            dependModules.append(dirList[j].fileName());
+                    }
+                }
+            }
+            for (int i = 0; i < dependModules.size(); i++) {
+                QString indexToAdd;
+                QList<QFileInfo> foundIndices;
+                for (int j = 0; j < indexDirs.size(); j++) {
+                    QString fileToLookFor = indexDirs[j] + QLatin1Char('/') + dependModules[i] +
+                            QLatin1Char('/') + dependModules[i] + QLatin1String(".index");
+                    if (QFile::exists(fileToLookFor)) {
+                        QFileInfo tempFileInfo(fileToLookFor);
+                        if (!foundIndices.contains(tempFileInfo))
+                            foundIndices.append(tempFileInfo);
+                    }
+                }
+                qSort(foundIndices.begin(), foundIndices.end(), creationTimeBefore);
+                if (foundIndices.size() > 1) {
+                    /*
+                        QDoc should always use the last entry in the multimap when there are
+                        multiple index files for a module, since the last modified file has the
+                        highest UNIX timestamp.
+                    */
+                    qDebug() << "Multiple indices found for dependency:" << dependModules[i] << "\nFound:";
+                    for (int k = 0; k < foundIndices.size(); k++)
+                        qDebug() << foundIndices[k].absoluteFilePath();
+                    qDebug() << "Using" << foundIndices[foundIndices.size() - 1].absoluteFilePath()
+                            << "as index for" << dependModules[i];
+                    indexToAdd = foundIndices[foundIndices.size() - 1].absoluteFilePath();
+                }
+                else if (foundIndices.size() == 1) {
+                    indexToAdd = foundIndices[0].absoluteFilePath();
+                }
+                if (!indexToAdd.isEmpty() && !indexFiles.contains(indexToAdd))
+                    indexFiles << indexToAdd;
+            }
+        }
+        else {
+            qDebug() << "Dependant modules specified, but no index directories or "
+                     << "install directory were set."
+                     << "There will probably be errors for missing links.";
+        }
+    }
+    qdb->readIndexes(indexFiles);
+}
+
 /*!
   Processes the qdoc config file \a fileName. This is the
   controller for all of qdoc.
@@ -168,8 +253,7 @@ static void processQdocconfFile(const QString &fileName)
     Config config(tr("qdoc"));
     int i = 0;
     while (defaults[i].key) {
-        config.setStringList(defaults[i].key,
-                             QStringList() << defaults[i].value);
+        config.setStringList(defaults[i].key, QStringList() << defaults[i].value);
         ++i;
     }
     config.setStringList(CONFIG_SYNTAXHIGHLIGHTING, QStringList(highlighting ? "true" : "false"));
@@ -177,8 +261,8 @@ static void processQdocconfFile(const QString &fileName)
     config.setStringList(CONFIG_NOLINKERRORS, QStringList(noLinkErrors ? "true" : "false"));
     config.setStringList(CONFIG_OBSOLETELINKS, QStringList(obsoleteLinks ? "true" : "false"));
 
-    QString documentationPath = QLibraryInfo::rawLocation(QLibraryInfo::DocumentationPath,
-                                                          QLibraryInfo::EffectivePaths);
+    documentationPath = QLibraryInfo::rawLocation(QLibraryInfo::DocumentationPath,
+                                                  QLibraryInfo::EffectivePaths);
 
     // Set a few environment variables that can be used from the qdocconf file
     qputenv("QT_INSTALL_DOCS", documentationPath.toLatin1());
@@ -202,10 +286,18 @@ static void processQdocconfFile(const QString &fileName)
     config.setStringList(CONFIG_DEFINES,defs);
     Location::terminate();
 
-    QString prevCurrentDir = QDir::currentPath();
-    QString dir = QFileInfo(fileName).path();
-    if (!dir.isEmpty())
-        QDir::setCurrent(dir);
+    prevCurrentDir = QDir::currentPath();
+    currentDir = QFileInfo(fileName).path();
+    if (!currentDir.isEmpty())
+        QDir::setCurrent(currentDir);
+
+    QString phase;
+    if (Generator::runPrepareOnly())
+        phase = "in -prepare mode ";
+    else if (Generator::runGenerateOnly())
+        phase = "in -generate mode ";
+    QString msg = "Running qdoc " + phase + "for " + config.getString(CONFIG_PROJECT);
+    Location::logToStdErr(msg);
 
     /*
       Initialize all the classes and data structures with the
@@ -227,8 +319,7 @@ static void processQdocconfFile(const QString &fileName)
     while (fn != fileNames.constEnd()) {
         QTranslator *translator = new QTranslator(0);
         if (!translator->load(*fn))
-            config.lastLocation().error(tr("Cannot load translator '%1'")
-                                        .arg(*fn));
+            config.lastLocation().error(tr("Cannot load translator '%1'").arg(*fn));
         QCoreApplication::instance()->installTranslator(translator);
         translators.append(translator);
         ++fn;
@@ -260,86 +351,8 @@ static void processQdocconfFile(const QString &fileName)
     QSet<QString> outputFormats = config.getOutputFormats();
     Location outputFormatsLocation = config.lastLocation();
 
-    /*
-      Read some XML indexes containing definitions from other documentation sets.
-     */
-    QStringList indexFiles = config.getStringList(CONFIG_INDEXES);
-
-    dependModules += config.getStringList(CONFIG_DEPENDS);
-
-    // Allow modules and third-party application/libraries to link
-    // to the Qt docs without having to explicitly pass --indexdir.
-    if (!indexDirs.contains(documentationPath))
-        indexDirs.append(documentationPath);
-
-    if (dependModules.size() > 0) {
-        if (indexDirs.size() > 0) {
-            for (int i = 0; i < indexDirs.size(); i++) {
-                if (indexDirs[i].startsWith("..")) {
-                    const QString prefix(QDir(dir).relativeFilePath(prevCurrentDir));
-                    if (!prefix.isEmpty())
-                        indexDirs[i].prepend(prefix + QLatin1Char('/'));
-                }
-            }
-            /*
-                Add all subdirectories of the indexdirs as dependModules when an asterisk is used in
-                the 'depends' list.
-            */
-            if (dependModules.contains("*")) {
-                dependModules.removeOne("*");
-                for (int i = 0; i < indexDirs.size(); i++) {
-                    QDir scanDir = QDir(indexDirs[i]);
-                    scanDir.setFilter(QDir::Dirs | QDir::NoDotAndDotDot);
-                    QFileInfoList dirList = scanDir.entryInfoList();
-                    for (int j = 0; j < dirList.size(); j++) {
-                        if (dirList[j].fileName().toLower() != config.getString(CONFIG_PROJECT).toLower())
-                            dependModules.append(dirList[j].fileName());
-                    }
-                }
-            }
-            for (int i = 0; i < dependModules.size(); i++) {
-                QString indexToAdd;
-                QList<QFileInfo> foundIndices;
-                for (int j = 0; j < indexDirs.size(); j++) {
-                    QString fileToLookFor = indexDirs[j] + QLatin1Char('/') + dependModules[i] +
-                            QLatin1Char('/') + dependModules[i] + QLatin1String(".index");
-                    if (QFile::exists(fileToLookFor)) {
-                        QFileInfo tempFileInfo(fileToLookFor);
-                        if (!foundIndices.contains(tempFileInfo))
-                            foundIndices.append(tempFileInfo);
-                    }
-                }
-                qSort(foundIndices.begin(), foundIndices.end(), creationTimeBefore);
-                if (foundIndices.size() > 1) {
-                    /*
-                        QDoc should always use the last entry in the multimap when there are
-                        multiple index files for a module, since the last modified file has the
-                        highest UNIX timestamp.
-                    */
-                    qDebug() << "Multiple indices found for dependency:" << dependModules[i] << "\nFound:";
-                    for (int k = 0; k < foundIndices.size(); k++)
-                        qDebug() << foundIndices[k].absoluteFilePath();
-                    qDebug() << "Using" << foundIndices[foundIndices.size() - 1].absoluteFilePath()
-                            << "as index for" << dependModules[i];
-                    indexToAdd = foundIndices[foundIndices.size() - 1].absoluteFilePath();
-                }
-                else if (foundIndices.size() == 1) {
-                    indexToAdd = foundIndices[0].absoluteFilePath();
-                }
-                else {
-                    qDebug() << "No indices for" << dependModules[i] <<
-                                "could be found in the specified index directories.";
-                }
-                if (!indexToAdd.isEmpty() && !indexFiles.contains(indexToAdd))
-                    indexFiles << indexToAdd;
-            }
-        }
-        else {
-            qDebug() << "Dependant modules specified, but no index directories or install directory were set."
-                     << "There will probably be errors for missing links.";
-        }
-    }
-    qdb->readIndexes(indexFiles);
+    if (!Generator::runPrepareOnly())
+        loadIndexFiles(config);
 
     QSet<QString> excludedDirs;
     QSet<QString> excludedFiles;
diff --git a/src/tools/qdoc/qdocindexfiles.cpp b/src/tools/qdoc/qdocindexfiles.cpp
index d68fe0e6fa..6d697c61b0 100644
--- a/src/tools/qdoc/qdocindexfiles.cpp
+++ b/src/tools/qdoc/qdocindexfiles.cpp
@@ -48,6 +48,7 @@
 #include "location.h"
 #include "atom.h"
 #include "generator.h"
+#include <qdebug.h>
 
 //include "doc.h"
 //include "htmlgenerator.h"
@@ -109,8 +110,11 @@ void QDocIndexFiles::destroyQDocIndexFiles()
  */
 void QDocIndexFiles::readIndexes(const QStringList& indexFiles)
 {
-    foreach (const QString& indexFile, indexFiles)
+    foreach (const QString& indexFile, indexFiles) {
+        QString msg = "  Loading index file: " + indexFile;
+        Location::logToStdErr(msg);
         readIndexFile(indexFile);
+    }
 }
 
 /*!
@@ -1048,6 +1052,9 @@ void QDocIndexFiles::generateIndex(const QString& fileName,
     if (!file.open(QFile::WriteOnly | QFile::Text))
         return;
 
+    QString msg = "  Writing index file: " + fileName;
+    Location::logToStdErr(msg);
+
     gen_ = g;
     QXmlStreamWriter writer(&file);
     writer.setAutoFormatting(true);