Improve 'rebuild index' under Windows: this often failed because of some

open files in the Xapian db (could not be deleted under windows).
Now only fails if a preview has been opened, and a GUI restart fixes the
situation.

src/qtgui/rclm_idx.cpp

@@ -29,6 +29,7 @@
 #include "rclmain_w.h"
 #include "specialindex.h"
 #include "readfile.h"
+#include "snippets_w.h"
 
 using namespace std;
 
@@ -291,8 +292,20 @@ void RclMain::toggleIndexing()
     }
 }
 
+static void delay(int millisecondsWait)
+{
+    QEventLoop loop;
+    QTimer t;
+    t.connect(&t, &QTimer::timeout, &loop, &QEventLoop::quit);
+    t.start(millisecondsWait);
+    loop.exec();
+}
+
 void RclMain::rebuildIndex()
 {
+    if (m_indexerState == IXST_UNKNOWN) {
+        delay(1500);
+    }
     switch (m_indexerState) {
     case IXST_UNKNOWN:
     case IXST_RUNNINGMINE:
@@ -313,12 +326,24 @@ void RclMain::rebuildIndex()
 					 QMessageBox::NoButton);
 	if (rep == QMessageBox::Ok) {
 #ifdef _WIN32
-            // Under windows, it's necessary to close the db here,
+            // Under windows, it is necessary to close the db here,
             // else Xapian won't be able to do what it wants with the
             // (open) files. Of course if there are several GUI
-            // instances, this won't work...
-            if (rcldb)
+            // instances, this won't work... Also it's quite difficult
+            // to make sure that there are no more references to the
+            // db because, for example of the Enquire objects inside
+            // Query inside Docsource etc.
+            //
+            // !! At this moment, this does not work if a preview has
+            // !! been opened. Could not find the reason (mysterious
+            // !! Xapian::Database reference somewhere?). The indexing
+            // !! fails, leaving a partial index directory. Then need
+            // !! to restart the GUI to succeed in reindexing.
+            if (rcldb) {
+                resetSearch();
+                deleteZ(m_snippets);
                 rcldb->close();
+            }
 #endif // _WIN32
 	    // Could also mean that no helpers are missing, but then we
 	    // won't try to show a message anyway (which is what

src/qtgui/rclm_wins.cpp

@@ -451,13 +451,16 @@ void RclMain::newDupsW(const Rcl::Doc, const vector<Rcl::Doc> dups)
 
 void RclMain::showSnippets(Rcl::Doc doc)
 {
-    SnippetsW *sp = new SnippetsW(doc, m_source);
-    connect(sp, SIGNAL(startNativeViewer(Rcl::Doc, int, QString)),
+    if (m_snippets) {
+        deleteZ(m_snippets);
+    }
+    m_snippets = new SnippetsW(doc, m_source);
+    connect(m_snippets, SIGNAL(startNativeViewer(Rcl::Doc, int, QString)),
 	    this, SLOT(startNativeViewer(Rcl::Doc, int, QString)));
-    connect(new QShortcut(quitKeySeq, sp), SIGNAL (activated()), 
+    connect(new QShortcut(quitKeySeq, m_snippets), SIGNAL (activated()), 
 	    this, SLOT (fileExit()));
-    connect(new QShortcut(closeKeySeq, sp), SIGNAL (activated()), 
-	    sp, SLOT (close()));
-    sp->show();
+    connect(new QShortcut(closeKeySeq, m_snippets), SIGNAL (activated()), 
+	    m_snippets, SLOT (close()));
+    m_snippets->show();
 }
 

src/qtgui/rclmain_w.cpp

@@ -531,7 +531,7 @@ void RclMain::initDbOpen()
 	    connect(fidia.idxschedCLB, SIGNAL(clicked()), 
 		    this, SLOT(execIndexSched()));
 	    connect(fidia.runidxPB, SIGNAL(clicked()), 
-		    this, SLOT(toggleIndexing()));
+		    this, SLOT(rebuildIndex()));
 	    fidia.exec();
 	    // Don't open adv search or run cmd line search in this case.
 	    return;
@@ -788,6 +788,7 @@ void RclMain::initiateQuery()
 
 void RclMain::resetSearch()
 {
+    m_source = std::shared_ptr<DocSequence>();
     emit searchReset();
 }
 
@@ -974,8 +975,7 @@ void RclMain::docExpand(Rcl::Doc doc)
 void RclMain::showDocHistory()
 {
     LOGDEB("RclMain::showDocHistory\n");
-    emit searchReset();
-    m_source = std::shared_ptr<DocSequence>();
+    resetSearch();
     curPreview = 0;
 
     string reason;

src/qtgui/rclmain_w.h

@@ -35,6 +35,7 @@
 #include "guiutils.h"
 #include "rclutil.h"
 
+class SnippetsW;
 class IdxSchedW;
 class ExecCmd;
 class Preview;
@@ -202,6 +203,7 @@ protected:
 
 
 private:
+    SnippetsW      *m_snippets{0};
     Preview        *curPreview;
     AdvSearch      *asearchform;
     UIPrefsDialog  *uiprefs;

src/qtgui/reslist.cpp

@@ -407,6 +407,8 @@ void ResList::setDocSource(std::shared_ptr<DocSequence> nsource)
 {
     LOGDEB("ResList::setDocSource()\n");
     m_source = std::shared_ptr<DocSequence>(new DocSource(theconfig, nsource));
+    if (m_pager)
+        m_pager->setDocSource(m_source);
 }
 
 // A query was executed, or the filtering/sorting parameters changed,

src/rcldb/rcldb.cpp

@@ -58,6 +58,7 @@ using namespace std;
 #include "rclinit.h"
 #include "internfile.h"
 #include "utf8fn.h"
+#include "wipedir.h"
 #ifdef RCL_USE_ASPELL
 #include "rclaspell.h"
 #endif
@@ -793,6 +794,15 @@ bool Db::open(OpenMode mode, OpenError *error)
 	case DbUpd:
 	case DbTrunc: 
 	    {
+                // Xapian is quite bad at erasing partial db which can
+                // occur because of open file deletion errors on
+                // Windows.
+                if (mode == DbTrunc) {
+                    if (path_exists(path_cat(dir, "iamchert"))) {
+                        wipedir(dir);
+                        unlink(dir.c_str());
+                    }
+                }
 		int action = (mode == DbUpd) ? Xapian::DB_CREATE_OR_OPEN :
 		    Xapian::DB_CREATE_OR_OVERWRITE;
                 if (::access(dir.c_str(), 0) != 0) {