Improvement to plugin_if_get_ws_info(...) functionality

A plugin can register an initialisation function to be called each time
Wireshark opens a new capture file. If plugin_if_get_ws_info(...) is
called from within the initialisation function it does not return the
name of the file being opened.  This is because
plugin_if_get_ws_info(...), through calls to a number of other
functions, gets the file name details from a capture_file structure.  At
the time of the call to the plugins initialisation function, the
capture_file structure in question has not yet been created.

This change ensures that if plugin_if_get_ws_info(...) is called from a
plugin's initialisation function, the name of the file to be open is
correctly returned. The change also fixes a bug where
plugin_if_ws_get(...) returns an incorrect file state if called from a
plugin initialisation function.

Bug: 14165
Change-Id: I28c85e480db96852e11bbaa14fb1f434b457ed52
Reviewed-on: https://code.wireshark.org/review/24251
Petri-Dish: Roland Knall <rknall@gmail.com>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>

3 files changed, 69 insertions, 12 deletions

diff --git a/ui/qt/main_window.cpp b/ui/qt/main_window.cpp
index c2f0718515..bbaced0077 100644
--- a/ui/qt/main_window.cpp
+++ b/ui/qt/main_window.cpp
@@ -179,30 +179,63 @@ static void plugin_if_mainwindow_get_ws_info(gconstpointer user_data)
 
     ws_info->ws_info_supported = true;
 
+    /* If we have a filename attached to ws_info clear it */
+    if (ws_info->cf_filename != NULL)
+    {
+        g_free(ws_info->cf_filename);
+        ws_info->cf_filename = NULL;
+    }
+
+    /* Determine the true state of the capture file.  We return the true state in
+    the ws_info structure and DON'T CHANGE the cf->state as we don't want to cause problems
+    with code that follows this. */
+    if (cf)
+    {
+        if (cf->filename)
+        {
+            /* As we have a cf->filename we'll use the name and the state */
+            ws_info->cf_filename = g_strdup(cf->filename);
+            ws_info->cf_state = cf->state;
+        }
+        else
+        {
+            /* When we come through here the cf->state can show FILE_READ_DONE even though the
+            file is actually closed (no filename). A better fix would be to have a
+            FILE_CLOSE_PENDING state but that involves a lot of code change elsewhere. */
+            ws_info->cf_state = FILE_CLOSED;
+        }
+    }
+
+    if (!ws_info->cf_filename)
+    {
+        /* We may have a filename associated with the main window so let's use it */
+        QString fileNameString = gbl_cur_main_window_->getMwFileName();
+        if (fileNameString.length())
+        {
+            QByteArray ba = fileNameString.toLatin1();
+            const char *c_file_name = ba.data();
+            ws_info->cf_filename = g_strdup(c_file_name);
+        }
+    }
+
     if (cf) {
-        ws_info->cf_state = cf->state;
         ws_info->cf_count = cf->count;
 
-        g_free(ws_info->cf_filename);
-        ws_info->cf_filename = g_strdup(cf->filename);
-
         if (cf->state == FILE_READ_DONE && cf->current_frame) {
             ws_info->cf_framenr = cf->current_frame->num;
             ws_info->frame_passed_dfilter = (cf->current_frame->flags.passed_dfilter == 1);
-        } else {
+        }
+        else {
             ws_info->cf_framenr = 0;
             ws_info->frame_passed_dfilter = FALSE;
         }
-    } else if (ws_info->cf_state != FILE_CLOSED) {
-        /* Initialise the ws_info structure */
+    }
+    else
+    {
+        /* Initialise the other ws_info structure values */
         ws_info->cf_count = 0;
-
-        g_free(ws_info->cf_filename);
-        ws_info->cf_filename = NULL;
-
         ws_info->cf_framenr = 0;
         ws_info->frame_passed_dfilter = FALSE;
-        ws_info->cf_state = FILE_CLOSED;
     }
 }
 
@@ -1890,6 +1923,9 @@ bool MainWindow::testCaptureFileClose(QString before_what, FileCloseContext cont
             return true;
         }
 #endif
+        /* Clear MainWindow file name details */
+        gbl_cur_main_window_->setMwFileName("");
+
         /* captureStop() will close the file if not having any packets */
         if (capture_file_.capFile() && context != Restart && context != Reload)
             // Don't really close if Restart or Reload
@@ -2829,6 +2865,17 @@ void MainWindow::removeAdditionalToolbar(QString toolbarName)
 
 }
 
+QString MainWindow::getMwFileName()
+{
+    return mwFileName_;
+}
+
+void MainWindow::setMwFileName(QString fileName)
+{
+    mwFileName_ = fileName;
+    return;
+}
+
 
 /*
  * Editor modelines
diff --git a/ui/qt/main_window.h b/ui/qt/main_window.h
index 77c8c35b03..74f95da95f 100644
--- a/ui/qt/main_window.h
+++ b/ui/qt/main_window.h
@@ -109,6 +109,9 @@ public:
     void addInterfaceToolbar(const iface_toolbar *toolbar_entry);
     void removeInterfaceToolbar(const gchar *menu_title);
 
+    QString getMwFileName();
+    void setMwFileName(QString fileName);
+
 protected:
     virtual bool eventFilter(QObject *obj, QEvent *event);
     virtual void keyPressEvent(QKeyEvent *event);
@@ -173,6 +176,10 @@ private:
     DragDropToolBar *filter_expression_toolbar_;
     bool was_maximized_;
 
+    /* the following values are maintained so that the capture file name and status
+    is available when there is no cf structure available */
+    QString mwFileName_;
+
     bool capture_stopping_;
     bool capture_filter_valid_;
 #ifdef HAVE_LIBPCAP
diff --git a/ui/qt/main_window_slots.cpp b/ui/qt/main_window_slots.cpp
index c4068eab80..2cced5b4c3 100644
--- a/ui/qt/main_window_slots.cpp
+++ b/ui/qt/main_window_slots.cpp
@@ -242,6 +242,9 @@ bool MainWindow::openCaptureFile(QString cf_path, QString read_filter, unsigned
             }
         }
 
+        /* Make the file name available via MainWindow */
+        setMwFileName(cf_path);
+
         /* Try to open the capture file. This closes the current file if it succeeds. */
         CaptureFile::globalCapFile()->window = this;
         if (cf_open(CaptureFile::globalCapFile(), cf_path.toUtf8().constData(), type, is_tempfile, &err) != CF_OK) {