Mute echo message if repeated or disabled

- Suppress messages with exactly same content as previously
  displayed within popup_mute_interval (24h by default). This parameter
  may be set on command line as "--popup_mute_interval n" where n is
  in hours.

- Command line option '--disable_popup_messages' disables all echo
  message popups (window and notification).

This patch only handles suppression of repeated messages during
reconnections.
TODO: Persist message history in the registry and use it to mute
repeated messages after disconnects and across restarts of the GUI.

Signed-off-by: Selva Nair <selva.nair@gmail.com>

echo.c

@@ -35,6 +35,8 @@
 #include "openvpn-gui-res.h"
 #include "localization.h"
 
+extern options_t o;
+
 /* echo msg types */
 #define ECHO_MSG_WINDOW (1)
 #define ECHO_MSG_NOTIFY (2)
@@ -80,12 +82,44 @@ echo_msg_add_fp(struct echo_msg *msg, time_t timestamp)
     return;
 }
 
-/* Add message to history -- update if already present */
+/* find message with given digest in history */
+static struct echo_msg_history *
+echo_msg_recall(const BYTE *digest, struct echo_msg_history *hist)
+{
+    for( ; hist; hist = hist->next)
+    {
+        if (memcmp(hist->fp.digest, digest, HASHLEN) == 0) break;
+    }
+    return hist;
+}
+
+/* Add an item to message history and return the head of the list */
+static struct echo_msg_history*
+echo_msg_history_add(struct echo_msg_history *head, const struct echo_msg_fp *fp)
+{
+    struct echo_msg_history *hist = malloc(sizeof(struct echo_msg_history));
+    if (hist)
+    {
+        memcpy(&hist->fp, fp, sizeof(*fp));
+        hist->next = head;
+        head = hist;
+    }
+    return head;
+}
+
+/* Save message in history -- update if already present */
 static void
 echo_msg_save(struct echo_msg *msg)
 {
-    /* Not implemented */
+    struct echo_msg_history *hist = echo_msg_recall(msg->fp.digest, msg->history);
-    return;
+    if (hist) /* update */
+    {
+        hist->fp.timestamp = msg->fp.timestamp;
+    }
+    else     /* add */
+    {
+        msg->history = echo_msg_history_add(msg->history, &msg->fp);
+    }
 }
 
 /* persist echo msg history to the registry */
@@ -108,8 +142,10 @@ echo_msg_load(connection_t *c)
 static BOOL
 echo_msg_repeated(const struct echo_msg *msg)
 {
-    /* Not implemented */
+    const struct echo_msg_history *hist;
-    return false;
+
+    hist = echo_msg_recall(msg->fp.digest, msg->history);
+    return (hist && (hist->fp.timestamp + o.popup_mute_interval*3600 > msg->fp.timestamp));
 }
 
 /* Append a line of echo msg */

openvpn_config.c

@@ -133,6 +133,10 @@ AddConfigFileToList(int config, const TCHAR *filename, const TCHAR *config_dir)
         if (IsKeyPassSaved(c->config_name))
             c->flags |= FLAG_SAVE_KEY_PASS;
     }
+    if (o.disable_popup_messages)
+    {
+        DisablePopupMessages(c);
+    }
 }
 
 #define FLAG_WARN_DUPLICATES        (0x1)

options.c

@@ -285,6 +285,15 @@ add_option(options_t *options, int i, TCHAR **p)
             exit(1);
         }
     }
+    else if (streq(p[0], _T("popup_mute_interval")) && p[1])
+    {
+        ++i;
+        options->popup_mute_interval = _ttoi(p[1]);
+    }
+    else if (streq(p[0], _T("disable_popup_messages")))
+    {
+        options->disable_popup_messages = 1;
+    }
     else
     {
         /* Unrecognized option or missing parameter */
@@ -679,3 +688,10 @@ DisableSavePasswords(connection_t *c)
     c->flags &= ~(FLAG_SAVE_AUTH_PASS | FLAG_SAVE_KEY_PASS);
     c->flags |= FLAG_DISABLE_SAVE_PASS;
 }
+
+/* Do not show popup messages generated by echo msg directives */
+void
+DisablePopupMessages(connection_t *c)
+{
+    c->flags |= FLAG_DISABLE_ECHO_MSG;
+}

options.h

@@ -207,6 +207,8 @@ typedef struct {
     DWORD disconnectscript_timeout;     /* Disconnect Script execution timeout (sec) */
     DWORD preconnectscript_timeout;     /* Preconnect Script execution timeout (sec) */
     DWORD config_menu_view;             /* 0 for auto, 1 for original flat menu, 2 for hierarchical */
+    DWORD disable_popup_messages;       /* set nonzero to suppress all echo msg messages */
+    DWORD popup_mute_interval;          /* Interval in hours to suppress repeated echo messages */
 
 #ifdef DEBUG
     FILE *debug_fp;
@@ -236,6 +238,7 @@ INT_PTR CALLBACK ScriptSettingsDlgProc(HWND hwndDlg, UINT msg, WPARAM wParam, LP
 INT_PTR CALLBACK ConnectionSettingsDlgProc(HWND hwndDlg, UINT msg, WPARAM wParam, LPARAM lParam);
 INT_PTR CALLBACK AdvancedSettingsDlgProc(HWND hwndDlg, UINT msg, WPARAM wParam, LPARAM lParam);
 void DisableSavePasswords(connection_t *);
+void DisablePopupMessages(connection_t *);
 
 void ExpandOptions(void);
 int CompareStringExpanded(const WCHAR *str1, const WCHAR *str2);

registry.c

@@ -63,6 +63,8 @@ struct regkey_int {
       {L"show_script_window", &o.show_script_window, 0},
       {L"service_only", &o.service_only, 0},
       {L"config_menu_view", &o.config_menu_view, CONFIG_VIEW_AUTO}
+      {L"popup_mute_interval", &o.popup_mute_interval, 24},
+      {L"disable_popup_messages", &o.disable_popup_messages, 0},
     };
 
 static int