Merge branch 'secret-service-check'

Check if secret service can be used under Unix.

See https://github.com/wxWidgets/wxWidgets/pull/1733

include/wx/private/secretstore.h

@@ -78,6 +78,8 @@ private:
 class wxSecretStoreImpl : public wxRefCounter
 {
 public:
+    virtual bool IsOk(wxString* WXUNUSED(errmsg)) const { return true; }
+
     virtual bool Save(const wxString& service,
                       const wxString& username,
                       const wxSecretValueImpl& password,

include/wx/secretstore.h

@@ -126,8 +126,9 @@ public:
     ~wxSecretStore();
 
 
-    // Check if this object is valid.
-    bool IsOk() const { return m_impl != NULL; }
+    // Check if this object is valid, i.e. can be used, and optionally fill in
+    // the provided error message string if it isn't.
+    bool IsOk(wxString* errmsg = NULL) const;
 
 
     // Store a username/password combination.

interface/wx/secretstore.h

@@ -166,14 +166,16 @@ public:
     Example of storing credentials using this class:
     @code
     wxSecretStore store = wxSecretStore::GetDefault();
-    if ( store.IsOk() )
+    wxString errmsg;
+    if ( store.IsOk(&errmsg) )
     {
         if ( !store.Save("MyApp/MyService", username, password) )
             wxLogWarning("Failed to save credentials to the system secret store.");
     }
     else
     {
-        wxLogWarning("This system doesn't support storing passwords securely.");
+        wxLogWarning("This system doesn't support storing passwords securely "
+                     "(%s).", errmsg);
     }
     @endcode
 
@@ -201,13 +203,20 @@ public:
         Returns the default secrets collection to use.
 
         Call IsOk() on the returned object to check if this method succeeded.
+
+        Note that this method may show a dialog to the user under some
+        platforms, so it can take an arbitrarily long time to return.
      */
     static wxSecretStore GetDefault();
 
     /**
-        Check if this object is valid.
+        Check if this object can actually be used.
+
+        @param errmsg If not @NULL, this parameter is filled with a
+            user-readable error message explaining why the secret store can't
+            be used (this argument is new since wxWidgets 3.1.4)
      */
-    bool IsOk() const;
+    bool IsOk(wxString* errmsg = NULL) const;
 
     /**
         Store a username/password combination.

samples/secretstore/secretstore.cpp

@@ -196,9 +196,11 @@ int main(int argc, char **argv)
     }
 
     wxSecretStore store = wxSecretStore::GetDefault();
-    if ( !store.IsOk() )
+    wxString errmsg;
+    if ( !store.IsOk(&errmsg) )
     {
-        wxFprintf(stderr, "Failed to create default secret store.\n");
+        wxFprintf(stderr, "Failed to create default secret store (%s)\n",
+                  errmsg);
         return EXIT_FAILURE;
     }
 

src/common/secretstore.cpp

@@ -162,6 +162,19 @@ wxSecretStore::~wxSecretStore()
 // Methods forwarded to wxSecretStoreImpl
 // ----------------------------------------------------------------------------
 
+bool
+wxSecretStore::IsOk(wxString* errmsg) const
+{
+    if ( !m_impl )
+    {
+        if ( errmsg )
+            *errmsg = _("Not available for this platform");
+        return false;
+    }
+
+    return m_impl->IsOk(errmsg);
+}
+
 bool
 wxSecretStore::Save(const wxString& service,
                     const wxString& user,

src/unix/secretstore.cpp

@@ -119,6 +119,52 @@ private:
     SecretValue* const m_value;
 };
 
+// Dummy implementation used when secret service is not available.
+class wxSecretStoreNotAvailableImpl : public wxSecretStoreImpl
+{
+public:
+    explicit wxSecretStoreNotAvailableImpl(const wxString& error)
+        : m_error(error)
+    {
+    }
+
+    virtual bool IsOk(wxString* errmsg) const wxOVERRIDE
+    {
+        if ( errmsg )
+            *errmsg = m_error;
+
+        return false;
+    }
+
+    virtual bool Save(const wxString& WXUNUSED(service),
+                      const wxString& WXUNUSED(user),
+                      const wxSecretValueImpl& WXUNUSED(secret),
+                      wxString& errmsg) wxOVERRIDE
+    {
+        errmsg = m_error;
+        return false;
+    }
+
+    virtual bool Load(const wxString& WXUNUSED(service),
+                      wxString* WXUNUSED(user),
+                      wxSecretValueImpl** WXUNUSED(secret),
+                      wxString& errmsg) const wxOVERRIDE
+    {
+        errmsg = m_error;
+        return false;
+    }
+
+    virtual bool Delete(const wxString& WXUNUSED(service),
+                        wxString& errmsg) wxOVERRIDE
+    {
+        errmsg = m_error;
+        return false;
+    }
+
+private:
+    const wxString m_error;
+};
+
 // This implementation uses synchronous libsecret functions which is supposed
 // to be a bad idea, but doesn't seem to be a big deal in practice and as there
 // is no simple way to implement asynchronous API under the other platforms, it
@@ -127,6 +173,25 @@ private:
 class wxSecretStoreLibSecretImpl : public wxSecretStoreImpl
 {
 public:
+    static wxSecretStoreLibSecretImpl* Create(wxString& errmsg)
+    {
+        wxGtkError error;
+        SecretService* const service = secret_service_get_sync
+                                       (
+                                            SECRET_SERVICE_OPEN_SESSION,
+                                            NULL,   // No cancellation
+                                            error.Out()
+                                       );
+        if ( !service )
+        {
+            errmsg = error.GetMessage();
+            return NULL;
+        }
+
+        // This passes ownership of service to the new object.
+        return new wxSecretStoreLibSecretImpl(service);
+    }
+
     virtual bool Save(const wxString& service,
                       const wxString& user,
                       const wxSecretValueImpl& secret,
@@ -142,7 +207,7 @@ public:
         wxGtkError error;
         if ( !secret_service_store_sync
               (
-                NULL,                           // Default service
+                m_service,
                 GetSchema(),
                 BuildAttributes(service, user),
                 SECRET_COLLECTION_DEFAULT,
@@ -167,7 +232,7 @@ public:
         wxGtkError error;
         GList* const found = secret_service_search_sync
             (
-                NULL,                           // Default service
+                m_service,
                 GetSchema(),
                 BuildAttributes(service),
                 static_cast<SecretSearchFlags>
@@ -209,8 +274,9 @@ public:
                         wxString& errmsg) wxOVERRIDE
     {
         wxGtkError error;
-        if ( !secret_password_clearv_sync
+        if ( !secret_service_clear_sync
               (
+                m_service,
                 GetSchema(),
                 BuildAttributes(service),
                 NULL,                           // Can't be cancelled
@@ -278,6 +344,15 @@ private:
                                 NULL
                             ));
     }
+
+    // Ctor is private, Create() should be used for creating objects of this
+    // class.
+    explicit wxSecretStoreLibSecretImpl(SecretService* service)
+        : m_service(service)
+    {
+    }
+
+    wxGtkObject<SecretService> m_service;
 };
 
 const char* wxSecretStoreLibSecretImpl::FIELD_SERVICE = "service";
@@ -298,8 +373,17 @@ wxSecretValueImpl* wxSecretValue::NewImpl(size_t size, const void *data)
 /* static */
 wxSecretStore wxSecretStore::GetDefault()
 {
-    // There is only a single store under Windows anyhow.
-    return wxSecretStore(new wxSecretStoreLibSecretImpl());
+    // Try to create the real implementation.
+    wxString errmsg;
+    wxSecretStoreImpl* impl = wxSecretStoreLibSecretImpl::Create(errmsg);
+    if ( !impl )
+    {
+        // But if we failed, fall back to a dummy one, so that we could at
+        // least return the error to the code using this class.
+        impl = new wxSecretStoreNotAvailableImpl(errmsg);
+    }
+
+    return wxSecretStore(impl);
 }
 
 #endif // wxUSE_SECRETSTORE