Add a Busy status to SyntaxLineEdit.

For CaptureFilterEdit it's possible to have an indeterminate state while
we're waiting on name resolution. Add a Busy status to SyntaxLineEdit
and set the text color to a mix of the normal foreground and background
colors (gray on most platforms).

Make the Busy state valid so that we don't have to wait on an
annoyingly-long name resolution to start capturing.

Update the global capture option filters using the main welcome capture
filter when we start a capture instead of when we've finished checking
the filter syntax.

Connect the CaptureFilterEdit returnPressed signal no matter what so
that we can start a capture by pressing return in the welcome screen
CaptureFilterEdit.

Add a fake resolution timeout to the CaptureFilterSyntaxWorker debug
code to make testing the different states easier.

Bug: 11950
Change-Id: I0cf01c0fbc0dd8065cdf5a91f1d6b224291b1ce6
Reviewed-on: https://code.wireshark.org/review/13110
Petri-Dish: Gerald Combs <gerald@wireshark.org>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Gerald Combs <gerald@wireshark.org>

8 files changed, 89 insertions, 50 deletions

diff --git a/ui/qt/capture_filter_edit.cpp b/ui/qt/capture_filter_edit.cpp
index bc8a2add37..c122c548f7 100644
--- a/ui/qt/capture_filter_edit.cpp
+++ b/ui/qt/capture_filter_edit.cpp
@@ -176,8 +176,8 @@ CaptureFilterEdit::CaptureFilterEdit(QWidget *parent, bool plain) :
                 "}"
                 );
         connect(apply_button_, SIGNAL(clicked()), this, SLOT(applyCaptureFilter()));
-        connect(this, SIGNAL(returnPressed()), this, SLOT(applyCaptureFilter()));
     }
+    connect(this, SIGNAL(returnPressed()), this, SLOT(applyCaptureFilter()));
 
     int frameWidth = style()->pixelMetric(QStyle::PM_DefaultFrameWidth);
     QSize bksz;
@@ -267,11 +267,11 @@ void CaptureFilterEdit::resizeEvent(QResizeEvent *)
     }
 }
 
-void CaptureFilterEdit::checkFilter(const QString& text)
+void CaptureFilterEdit::checkFilter(const QString& filter)
 {
-    setSyntaxState(Empty);
+    setSyntaxState(Busy);
     popFilterSyntaxStatus();
-    bool empty = text.isEmpty();
+    bool empty = filter.isEmpty();
 
     if (bookmark_button_) {
         bookmark_button_->setEnabled(false);
@@ -286,9 +286,9 @@ void CaptureFilterEdit::checkFilter(const QString& text)
     }
 
     if (empty) {
-        setFilterSyntaxState(text, Empty, QString());
+        setFilterSyntaxState(filter, Empty, QString());
     } else {
-        syntax_worker_->checkFilter(text);
+        syntax_worker_->checkFilter(filter);
     }
 }
 
@@ -306,8 +306,6 @@ void CaptureFilterEdit::initCaptureFilter()
 
 void CaptureFilterEdit::setFilterSyntaxState(QString filter, int state, QString err_msg)
 {
-    bool valid = (state != Invalid);
-
     if (filter.compare(text()) == 0) { // The user hasn't changed the filter
         setSyntaxState((SyntaxState)state);
         if (!err_msg.isEmpty()) {
@@ -315,43 +313,16 @@ void CaptureFilterEdit::setFilterSyntaxState(QString filter, int state, QString
         }
     }
 
-#ifdef HAVE_LIBPCAP
-    if (syntaxState() != Invalid) {
+    bool valid = (state != Invalid);
+
+    if (valid) {
         if (bookmark_button_) {
             bookmark_button_->setEnabled(true);
         }
         if (apply_button_) {
             apply_button_->setEnabled(true);
         }
-        valid = true;
-        g_free(global_capture_opts.default_options.cfilter);
-        if (filter.isEmpty()) {
-            global_capture_opts.default_options.cfilter = NULL;
-        } else {
-            global_capture_opts.default_options.cfilter = qstring_strdup(filter);
-        }
-
-        if (global_capture_opts.num_selected > 0) {
-            interface_t device;
-
-            for (guint i = 0; i < global_capture_opts.all_ifaces->len; i++) {
-                device = g_array_index(global_capture_opts.all_ifaces, interface_t, i);
-                if (!device.selected) {
-                    continue;
-                }
-//                if (device.active_dlt == -1) {
-//                    simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, "The link type of interface %s was not specified.", device.name);
-//                    continue;  /* Programming error: somehow managed to select an "unsupported" entry */
-//                }
-                g_array_remove_index(global_capture_opts.all_ifaces, i);
-                g_free(device.cfilter);
-                device.cfilter = qstring_strdup(filter);
-                g_array_insert_val(global_capture_opts.all_ifaces, i, device);
-//                update_filter_string(device.name, filter_text);
-            }
-        }
     }
-#endif // HAVE_LIBPCAP
 
     emit captureFilterSyntaxChanged(valid);
 }
diff --git a/ui/qt/capture_filter_edit.h b/ui/qt/capture_filter_edit.h
index cbfd1ef6b8..7250bba6b2 100644
--- a/ui/qt/capture_filter_edit.h
+++ b/ui/qt/capture_filter_edit.h
@@ -49,7 +49,7 @@ public slots:
 private slots:
     void initCaptureFilter();
     void applyCaptureFilter();
-    void checkFilter(const QString &text);
+    void checkFilter(const QString &filter);
     void setFilterSyntaxState(QString filter, int state, QString err_msg);
     void bookmarkClicked();
 
diff --git a/ui/qt/capture_filter_syntax_worker.cpp b/ui/qt/capture_filter_syntax_worker.cpp
index e38e0e05c9..29cf4c1452 100644
--- a/ui/qt/capture_filter_syntax_worker.cpp
+++ b/ui/qt/capture_filter_syntax_worker.cpp
@@ -44,8 +44,10 @@ static QMutex pcap_compile_mtx_;
 #include <QDebug>
 #include <QThread>
 #define DEBUG_SYNTAX_CHECK(state1, state2) qDebug() << "CF state" << QThread::currentThreadId() << state1 << "->" << state2 << ":" << filter_text_ << ":" << filter
+#define DEBUG_SLEEP_TIME 5000 // ms
 #else
 #define DEBUG_SYNTAX_CHECK(state1, state2)
+#define DEBUG_SLEEP_TIME 0 // ms
 #endif
 
 #define DUMMY_SNAPLENGTH                65535
@@ -102,6 +104,10 @@ void CaptureFilterSyntaxWorker::start() {
             pc_err = pcap_compile(pd, &fcode, filter.toUtf8().constData(), 1 /* Do optimize */, 0);
 #endif
 
+#if DEBUG_SLEEP_TIME > 0
+            QThread::msleep(DEBUG_SLEEP_TIME);
+#endif
+
             if (pc_err) {
                 DEBUG_SYNTAX_CHECK("unknown", "known bad");
                 state = SyntaxLineEdit::Invalid;
diff --git a/ui/qt/main_welcome.cpp b/ui/qt/main_welcome.cpp
index 667fbf582a..1e20dbc229 100644
--- a/ui/qt/main_welcome.cpp
+++ b/ui/qt/main_welcome.cpp
@@ -204,6 +204,11 @@ InterfaceTree *MainWelcome::getInterfaceTree()
     return welcome_ui_->interfaceTree;
 }
 
+const QString MainWelcome::captureFilter()
+{
+    return welcome_ui_->captureFilterComboBox->currentText();
+}
+
 void MainWelcome::appInitialized()
 {
     // XXX Add a "check for updates" link?
diff --git a/ui/qt/main_welcome.h b/ui/qt/main_welcome.h
index 18574cbabf..37676a5941 100644
--- a/ui/qt/main_welcome.h
+++ b/ui/qt/main_welcome.h
@@ -42,6 +42,7 @@ public:
     explicit MainWelcome(QWidget *parent = 0);
     virtual ~MainWelcome();
     InterfaceTree *getInterfaceTree();
+    const QString captureFilter();
 
 protected:
     void resizeEvent(QResizeEvent *event);
diff --git a/ui/qt/main_window_slots.cpp b/ui/qt/main_window_slots.cpp
index 92da379b81..f0b78574d5 100644
--- a/ui/qt/main_window_slots.cpp
+++ b/ui/qt/main_window_slots.cpp
@@ -837,6 +837,36 @@ void MainWindow::startCapture() {
 
     /* XXX - we might need to init other pref data as well... */
 
+    // Set our cfilters.
+    QString capture_filter = main_welcome_->captureFilter();
+    g_free(global_capture_opts.default_options.cfilter);
+    if (capture_filter.isEmpty()) {
+        global_capture_opts.default_options.cfilter = NULL;
+    } else {
+        global_capture_opts.default_options.cfilter = qstring_strdup(capture_filter);
+    }
+
+    if (global_capture_opts.num_selected > 0) {
+        interface_t device;
+
+        for (guint i = 0; i < global_capture_opts.all_ifaces->len; i++) {
+            device = g_array_index(global_capture_opts.all_ifaces, interface_t, i);
+            if (!device.selected) {
+                continue;
+            }
+            //                if (device.active_dlt == -1) {
+            //                    simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, "The link type of interface %s was not specified.", device.name);
+            //                    continue;  /* Programming error: somehow managed to select an "unsupported" entry */
+            //                }
+            g_array_remove_index(global_capture_opts.all_ifaces, i);
+            g_free(device.cfilter);
+            device.cfilter = qstring_strdup(capture_filter);
+            g_array_insert_val(global_capture_opts.all_ifaces, i, device);
+            //                update_filter_string(device.name, filter_text);
+        }
+    }
+
+
     /* XXX - can this ever happen? */
     if (cap_session_.state != CAPTURE_STOPPED)
       return;
diff --git a/ui/qt/syntax_line_edit.cpp b/ui/qt/syntax_line_edit.cpp
index 3d0e6e2cde..ce898b8f58 100644
--- a/ui/qt/syntax_line_edit.cpp
+++ b/ui/qt/syntax_line_edit.cpp
@@ -39,6 +39,10 @@
 #include <QStringListModel>
 #include <limits>
 
+// To do:
+// - Add indicator icons for syntax states to make things more clear for
+//   color blind people?
+
 const int max_completion_items_ = 20;
 
 SyntaxLineEdit::SyntaxLineEdit(QWidget *parent) :
@@ -46,6 +50,13 @@ SyntaxLineEdit::SyntaxLineEdit(QWidget *parent) :
     completer_(NULL),
     completion_model_(NULL)
 {
+    // Try to matche QLineEdit's placeholder text color (which sets the
+    // alpha channel to 50%, which doesn't work in style sheets).
+    // Setting the foreground color lets us avoid yet another background
+    // color preference and should hopefully make things easier to
+    // distinguish for color blind folk.
+    busy_fg_ = ColorUtils::alphaBlend(palette().text(), palette().base(), 0.5);
+
     setSyntaxState();
     setMaxLength(std::numeric_limits<quint32>::max());
 }
@@ -75,27 +86,41 @@ void SyntaxLineEdit::setSyntaxState(SyntaxState state) {
     syntax_state_ = state;
     state_style_sheet_ = QString(
             "SyntaxLineEdit[syntaxState=\"%1\"] {"
-            "  color: %4;"
-            "  background-color: %5;"
+            "  color: %5;"
+            "  background-color: %7;"
             "}"
 
             "SyntaxLineEdit[syntaxState=\"%2\"] {"
-            "  color: %4;"
-            "  background-color: %6;"
+            "  color: %5;"
+            "  background-color: %8;"
             "}"
 
             "SyntaxLineEdit[syntaxState=\"%3\"] {"
-            "  color: %4;"
-            "  background-color: %7;"
+            "  color: %5;"
+            "  background-color: %9;"
+            "}"
+
+            "SyntaxLineEdit[syntaxState=\"%4\"] {"
+            "  color: %10;"
+            "  background-color: %6;"
             "}"
             )
+
+            // CSS selectors
             .arg(Valid)
             .arg(Invalid)
             .arg(Deprecated)
-            .arg("palette(text)")   // Foreground
-            .arg(ColorUtils::fromColorT(&prefs.gui_text_valid).name())        // Valid
-            .arg(ColorUtils::fromColorT(&prefs.gui_text_invalid).name())      // Invalid
-            .arg(ColorUtils::fromColorT(&prefs.gui_text_deprecated).name())   // Deprecated
+            .arg(Busy)
+
+            // Normal foreground / background
+            .arg("palette(text)")
+            .arg("palette(base)")
+
+            // Special foreground / background
+            .arg(ColorUtils::fromColorT(&prefs.gui_text_valid).name())
+            .arg(ColorUtils::fromColorT(&prefs.gui_text_invalid).name())
+            .arg(ColorUtils::fromColorT(&prefs.gui_text_deprecated).name())
+            .arg(busy_fg_.name())
             ;
     setStyleSheet(style_sheet_);
 }
diff --git a/ui/qt/syntax_line_edit.h b/ui/qt/syntax_line_edit.h
index f76e6bc626..3184e7a81d 100644
--- a/ui/qt/syntax_line_edit.h
+++ b/ui/qt/syntax_line_edit.h
@@ -38,7 +38,7 @@ class SyntaxLineEdit : public QLineEdit
     Q_ENUMS(SyntaxState)
 public:
     explicit SyntaxLineEdit(QWidget *parent = 0);
-    enum SyntaxState { Empty, Invalid, Deprecated, Valid };
+    enum SyntaxState { Empty, Busy, Invalid, Deprecated, Valid };
 
     SyntaxState syntaxState() const { return syntax_state_; }
     void setSyntaxState(SyntaxState state = Empty);
@@ -79,6 +79,7 @@ private:
     QString deprecated_token_;
     QString syntax_error_message_;
     QString token_chars_;
+    QColor busy_fg_;
 
 private slots:
     void insertFieldCompletion(const QString &completion_text);