add support for "live"-flashing new settings.

8 files changed, 962 insertions, 113 deletions

diff --git a/src/server/gtk.c b/src/server/gtk.c
index 36b36bb..f48d1d9 100644
--- a/src/server/gtk.c
+++ b/src/server/gtk.c
@@ -20,6 +20,7 @@
 
 #include <gtk/gtk.h>
 #include <time.h>
+#include <stdlib.h>
 #include <string.h>
 #include "util.h"
 #include "gtk.h"
@@ -37,20 +38,45 @@ struct gtkui {
 	GObject *voltage;
 	GObject *reslabel;
 	GObject *voltlabel;
-	GObject *showmorebutton;
-	GObject *button_on;
-	GObject *button_off;
+	GObject *show_more;
+	GObject *show_less;
 	GObject *ticker;
 	GError *error;
 	int showmore;
 };
 
+struct gtkui_flash {
+	GtkBuilder *builder;
+	GObject *window;
+	GObject *ssid;
+	GObject *password;
+	GObject *htemp;
+	GObject *mhtemp;
+	GObject *mltemp;
+	GObject *ltemp;
+	GObject *flashdialog;
+	GObject *dialog_ok;
+	GObject *dialog_text;
+	const char *confdata[6];
+	int close_with_dialog;
+};
+
 static struct settings settings;
 static struct gtkui gtkui;
+static struct gtkui_flash gtkui_flash;
 
 static int gtkui_update(void *data);
 static void gtkui_die(void *data);
-static void gtkui_togglemore(void);
+static int strtokel(const char * const s);
+void gtkui_togglemore(void);
+void gtkui_flashwindow_create(void);
+void gtkui_flashwindow_destroy(void);
+void gtkui_flashwindow_clean(void);
+void gtkui_issue_flash_request(void);
+void gtkui_readhtemp(void);
+void gtkui_readmhtemp(void);
+void gtkui_readmltemp(void);
+void gtkui_readltemp(void);
 
 int gtkui_init(int *argc, char ***argv, int nd, struct timespec period)
 {
@@ -66,10 +92,7 @@ int gtkui_init(int *argc, char ***argv, int nd, struct timespec period)
 
 	gtkui.builder = gtk_builder_new();
 
-	if (!gtk_builder_add_from_file(gtkui.builder, DATA_DIR "/gtklayout.ui", &gtkui.error)) {
-		ret = ERROR;
-		goto fail;
-	}
+	gtkui.builder = gtk_builder_new_from_file(DATA_DIR "/gtklayout.ui");
 
 	gtkui.window = gtk_builder_get_object(gtkui.builder, "window");
 	gtkui.tempvalue = gtk_builder_get_object(gtkui.builder, "tempvalue");
@@ -77,12 +100,13 @@ int gtkui_init(int *argc, char ***argv, int nd, struct timespec period)
 	gtkui.voltage = gtk_builder_get_object(gtkui.builder, "voltage");
 	gtkui.reslabel = gtk_builder_get_object(gtkui.builder, "reslabel");
 	gtkui.voltlabel = gtk_builder_get_object(gtkui.builder, "voltlabel");
-	gtkui.showmorebutton = gtk_builder_get_object(gtkui.builder, "showmore");
-	gtkui.button_on = gtk_builder_get_object(gtkui.builder, "button_on");
-	gtkui.button_off = gtk_builder_get_object(gtkui.builder, "button_off");
+	gtkui.show_more = gtk_builder_get_object(gtkui.builder, "show_more");
+	gtkui.show_less = gtk_builder_get_object(gtkui.builder, "show_less");
 	gtkui.ticker = gtk_builder_get_object(gtkui.builder, "ticker");
-	g_signal_connect(gtkui.window, "destroy", G_CALLBACK(gtk_main_quit), NULL);
-	g_signal_connect(gtkui.showmorebutton, "toggled", G_CALLBACK(gtkui_togglemore), NULL);
+	gtk_builder_connect_signals(gtkui.builder, NULL);
+	g_object_unref(G_OBJECT(gtkui.builder));
+	gtkui.builder = NULL;
+
 	gtkui.showmore = 1; /* we are setting this so we can toggle this off on the following call */
 	gtkui_togglemore();
 
@@ -137,13 +161,165 @@ static void gtkui_die(void *data)
 	return;
 }
 
-static void gtkui_togglemore(void)
+static int strtokel(const char * const s)
+{
+	int ret;
+
+	ret = atoi(s);
+	ret += 273;
+	ret *= 10;
+
+	return ret;
+}
+
+void gtkui_togglemore(void)
 {
 	gtkui.showmore = !gtkui.showmore;
-	gtkui.showmore ? gtk_button_set_image(GTK_BUTTON(gtkui.showmorebutton), GTK_WIDGET(gtkui.button_on)) :
-				gtk_button_set_image(GTK_BUTTON(gtkui.showmorebutton), GTK_WIDGET(gtkui.button_off));
-	gtk_widget_set_visible (GTK_WIDGET(gtkui.resistance), gtkui.showmore);
-	gtk_widget_set_visible (GTK_WIDGET(gtkui.voltage), gtkui.showmore);
-	gtk_widget_set_visible (GTK_WIDGET(gtkui.reslabel), gtkui.showmore);
-	gtk_widget_set_visible (GTK_WIDGET(gtkui.voltlabel), gtkui.showmore);
+
+	/* this actually switches them around their state */
+	gtk_widget_set_visible(GTK_WIDGET(gtkui.show_more), !gtkui.showmore);
+	gtk_widget_set_visible(GTK_WIDGET(gtkui.show_less), gtkui.showmore);
+
+	gtk_widget_set_visible(GTK_WIDGET(gtkui.resistance), gtkui.showmore);
+	gtk_widget_set_visible(GTK_WIDGET(gtkui.voltage), gtkui.showmore);
+	gtk_widget_set_visible(GTK_WIDGET(gtkui.reslabel), gtkui.showmore);
+	gtk_widget_set_visible(GTK_WIDGET(gtkui.voltlabel), gtkui.showmore);
+}
+
+void gtkui_flashwindow_create(void)
+{
+	if (gtkui_flash.window) {
+		goto fail;
+	}
+
+	gtkui_flash.builder = gtk_builder_new_from_file(DATA_DIR "/gtklayout_flash.ui");
+	gtkui_flash.window = gtk_builder_get_object(gtkui_flash.builder, "flashwindow");
+	gtkui_flash.ssid = gtk_builder_get_object(gtkui_flash.builder, "ssid_entry");
+	gtkui_flash.password = gtk_builder_get_object(gtkui_flash.builder, "pass_entry");
+	gtkui_flash.htemp = gtk_builder_get_object(gtkui_flash.builder, "htemp_entry");
+	gtkui_flash.mhtemp = gtk_builder_get_object(gtkui_flash.builder, "mhtemp_entry");
+	gtkui_flash.mltemp = gtk_builder_get_object(gtkui_flash.builder, "mltemp_entry");
+	gtkui_flash.ltemp = gtk_builder_get_object(gtkui_flash.builder, "ltemp_entry");
+	gtkui_flash.flashdialog = gtk_builder_get_object(gtkui_flash.builder, "flashdialog");
+	gtkui_flash.dialog_ok = gtk_builder_get_object(gtkui_flash.builder, "dialog_ok");
+	gtkui_flash.dialog_text = gtk_builder_get_object(gtkui_flash.builder, "dialog_text");
+	gtk_builder_connect_signals(gtkui_flash.builder, NULL);
+	g_object_unref(G_OBJECT(gtkui_flash.builder));
+	gtkui_flash.builder = NULL;
+
+fail:
+	return;
+}
+
+void gtkui_window_destroy(void *window)
+{
+	gtk_window_close(GTK_WINDOW(window));
+}
+
+void gtkui_flashwindow_clean(void)
+{
+	gtkui_flash.window = NULL;
+}
+
+void gtkui_issue_flash_request(void)
+{
+	static const struct configuration def = {{{
+		PADDING_START,
+		"ssid",				/* ssid */
+		"password",			/* password */
+		{3330, 3230, 3130, 3030},	/* calibration */
+		PADDING_END
+	}}};
+
+	struct configuration conf;
+	size_t i;
+	size_t len;
+	const char *tmp;
+
+	gtk_widget_set_visible(GTK_WIDGET(gtkui_flash.flashdialog), 1);
+
+	for (i = 0; i < sizeof (gtkui_flash.confdata); ++i) {
+		switch (i) {
+		case 0:
+			tmp = gtkui_flash.confdata[i] ? gtkui_flash.confdata[i] : def.ssid;
+			len = strlen(tmp) > (sizeof(conf.ssid) - 1) ? sizeof(conf.ssid) - 1 : strlen(tmp);
+			memcpy(conf.ssid, tmp, len);
+			conf.ssid[len] = '\0';
+			break;
+		case 1:
+			tmp = gtkui_flash.confdata[i] ? gtkui_flash.confdata[i] : def.password;
+			len = strlen(tmp) > (sizeof(conf.password) - 1) ? sizeof(conf.password) - 1 : strlen(tmp);
+			memcpy(conf.password, tmp, len);
+			conf.password[len] = '\0';
+			break;
+		case 2:
+		case 3:
+		case 4:
+		case 5:
+			tmp = gtkui_flash.confdata[i] ? (char *) strlen(gtkui_flash.confdata[i]) : NULL;
+			conf.calibration[i - 2] = tmp ? strtokel(gtkui_flash.confdata[i]) : def.calibration[i -2];
+			break;
+		default:
+			break;
+		}
+
+	}
+
+	write_settings(DATA_DIR "/fw.bin", &conf);
+}
+
+void gtkui_readssid(void)
+{
+	gtkui_flash.confdata[0] = gtk_entry_get_text(GTK_ENTRY(gtkui_flash.ssid));
+}
+
+void gtkui_readpass(void)
+{
+	gtkui_flash.confdata[1] = gtk_entry_get_text(GTK_ENTRY(gtkui_flash.password));
+}
+
+void gtkui_readhtemp(void)
+{
+	gtkui_flash.confdata[2] = gtk_entry_get_text(GTK_ENTRY(gtkui_flash.htemp));
+}
+
+void gtkui_readmhtemp(void)
+{
+	gtkui_flash.confdata[3] = gtk_entry_get_text(GTK_ENTRY(gtkui_flash.mhtemp));
+}
+
+void gtkui_readmltemp(void)
+{
+	gtkui_flash.confdata[4] = gtk_entry_get_text(GTK_ENTRY(gtkui_flash.mltemp));
+}
+
+void gtkui_readltemp(void)
+{
+	gtkui_flash.confdata[5] = gtk_entry_get_text(GTK_ENTRY(gtkui_flash.ltemp));
+}
+
+void gtkui_manhandle_flashdialog(void *dialog)
+{
+	gtk_label_set_markup(GTK_LABEL(gtkui_flash.dialog_text), "Writing to flash...     ");
+	if (gtkui_flash.close_with_dialog) {
+		gtk_widget_destroy(GTK_WIDGET(dialog));
+		/* we also want to close tha parent */
+		gtk_window_close(GTK_WINDOW(gtkui_flash.window));
+	} else {
+		gtk_widget_set_visible(GTK_WIDGET(dialog), 0);
+	}
+}
+
+void gtkui_dialog_done(int status)
+{
+	static const char * const text[2] = {"done", "FAIL"};
+	static const char * const color[2] = {"#4E9A06", "#EF2929"};
+	char msg[128];
+
+	status = status ? 1 : status;
+	gtkui_flash.close_with_dialog = !status;
+	sprintf(msg, "Writing to flash... <span foreground=\"%s\" font_weight=\"bold\">%s!</span>", color[status], text[status]);
+
+	gtk_widget_set_sensitive(GTK_WIDGET(gtkui_flash.dialog_ok), 1);
+	gtk_label_set_markup(GTK_LABEL(gtkui_flash.dialog_text), msg);
 }
diff --git a/src/server/gtk.h b/src/server/gtk.h
index 0c47b0b..ad739e5 100644
--- a/src/server/gtk.h
+++ b/src/server/gtk.h
@@ -27,5 +27,6 @@
 
 int gtkui_init(int *argc, char ***argv, int nd, struct timespec period);
 int gtkui_loop(void);
+void gtkui_dialog_done(int status);
 
 #endif /* GTK_H_INCLUDED */
diff --git a/src/server/gtk.o b/src/server/gtk.o
deleted file mode 100644
index 0c2098d..0000000
--- a/src/server/gtk.o
+++ /dev/null
diff --git a/src/server/gtklayout.ui b/src/server/gtklayout.ui
index 69fd947..e6d3f5a 100644
--- a/src/server/gtklayout.ui
+++ b/src/server/gtklayout.ui
@@ -2,12 +2,17 @@
 <!-- Generated with glade 3.20.0 -->
 <interface>
   <requires lib="gtk+" version="3.20"/>
-  <object class="GtkImage" id="button_off">
+  <object class="GtkImage" id="gtk-flash">
+    <property name="visible">True</property>
+    <property name="can_focus">False</property>
+    <property name="stock">gtk-properties</property>
+  </object>
+  <object class="GtkImage" id="gtk-no-stock">
     <property name="visible">True</property>
     <property name="can_focus">False</property>
     <property name="stock">gtk-no</property>
   </object>
-  <object class="GtkImage" id="button_on">
+  <object class="GtkImage" id="gtk-yes-stock">
     <property name="visible">True</property>
     <property name="can_focus">False</property>
     <property name="stock">gtk-yes</property>
@@ -15,112 +20,260 @@
   <object class="GtkWindow" id="window">
     <property name="visible">True</property>
     <property name="can_focus">False</property>
-    <property name="title" translatable="yes">Coffeetemp</property>
     <property name="resizable">False</property>
+    <signal name="destroy" handler="gtk_main_quit" swapped="no"/>
     <child>
-      <object class="GtkGrid">
+      <object class="GtkBox">
         <property name="visible">True</property>
         <property name="can_focus">False</property>
+        <property name="orientation">vertical</property>
         <child>
-          <object class="GtkLabel" id="ticker">
-            <property name="visible">True</property>
-            <property name="can_focus">False</property>
-          </object>
-          <packing>
-            <property name="left_attach">0</property>
-            <property name="top_attach">0</property>
-          </packing>
-        </child>
-        <child>
-          <object class="GtkLabel">
-            <property name="visible">True</property>
-            <property name="can_focus">False</property>
-            <property name="label" translatable="yes"> Temperature: </property>
-          </object>
-          <packing>
-            <property name="left_attach">1</property>
-            <property name="top_attach">0</property>
-          </packing>
-        </child>
-        <child>
-          <object class="GtkLabel" id="tempvalue">
-            <property name="visible">True</property>
-            <property name="can_focus">False</property>
-          </object>
-          <packing>
-            <property name="left_attach">2</property>
-            <property name="top_attach">0</property>
-          </packing>
-        </child>
-        <child>
-          <object class="GtkToggleButton" id="showmore">
-            <property name="label" translatable="yes">show all</property>
-            <property name="visible">True</property>
-            <property name="can_focus">True</property>
-            <property name="receives_default">True</property>
-            <property name="image">button_on</property>
-            <property name="always_show_image">True</property>
-            <property name="draw_indicator">True</property>
-          </object>
-          <packing>
-            <property name="left_attach">3</property>
-            <property name="top_attach">0</property>
-          </packing>
-        </child>
-        <child>
-          <object class="GtkLabel" id="reslabel">
-            <property name="visible">True</property>
-            <property name="can_focus">False</property>
-            <property name="label" translatable="yes"> Resistence: </property>
-          </object>
-          <packing>
-            <property name="left_attach">1</property>
-            <property name="top_attach">1</property>
-          </packing>
-        </child>
-        <child>
-          <object class="GtkLabel" id="resistance">
-            <property name="visible">True</property>
-            <property name="can_focus">False</property>
-          </object>
-          <packing>
-            <property name="left_attach">2</property>
-            <property name="top_attach">1</property>
-          </packing>
-        </child>
-        <child>
-          <object class="GtkLabel" id="voltage">
+          <object class="GtkMenuBar" id="menu">
             <property name="visible">True</property>
             <property name="can_focus">False</property>
+            <child>
+              <object class="GtkMenuItem">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="label" translatable="yes">_File</property>
+                <property name="use_underline">True</property>
+                <child type="submenu">
+                  <object class="GtkMenu">
+                    <property name="visible">True</property>
+                    <property name="can_focus">False</property>
+                    <child>
+                      <object class="GtkImageMenuItem">
+                        <property name="label">gtk-quit</property>
+                        <property name="visible">True</property>
+                        <property name="can_focus">False</property>
+                        <property name="use_underline">True</property>
+                        <property name="use_stock">True</property>
+                        <property name="always_show_image">True</property>
+                        <signal name="activate" handler="gtk_main_quit" swapped="no"/>
+                      </object>
+                    </child>
+                  </object>
+                </child>
+              </object>
+            </child>
+            <child>
+              <object class="GtkMenuItem">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="label" translatable="yes">_Edit</property>
+                <property name="use_underline">True</property>
+                <child type="submenu">
+                  <object class="GtkMenu">
+                    <property name="visible">True</property>
+                    <property name="can_focus">False</property>
+                    <child>
+                      <object class="GtkImageMenuItem">
+                        <property name="label">_Reflash</property>
+                        <property name="visible">True</property>
+                        <property name="can_focus">False</property>
+                        <property name="use_underline">True</property>
+                        <property name="image">gtk-flash</property>
+                        <property name="use_stock">False</property>
+                        <property name="always_show_image">True</property>
+                        <signal name="activate" handler="gtkui_flashwindow_create" swapped="no"/>
+                      </object>
+                    </child>
+                  </object>
+                </child>
+              </object>
+            </child>
+            <child>
+              <object class="GtkMenuItem">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="label" translatable="yes">_View</property>
+                <property name="use_underline">True</property>
+                <child type="submenu">
+                  <object class="GtkMenu">
+                    <property name="visible">True</property>
+                    <property name="can_focus">False</property>
+                    <child>
+                      <object class="GtkImageMenuItem" id="show_more">
+                        <property name="label">Show _more</property>
+                        <property name="visible">True</property>
+                        <property name="can_focus">False</property>
+                        <property name="use_underline">True</property>
+                        <property name="image">gtk-yes-stock</property>
+                        <property name="use_stock">False</property>
+                        <property name="always_show_image">True</property>
+                        <signal name="activate" handler="gtkui_togglemore" swapped="no"/>
+                      </object>
+                    </child>
+                    <child>
+                      <object class="GtkImageMenuItem" id="show_less">
+                        <property name="label">Show _less</property>
+                        <property name="can_focus">False</property>
+                        <property name="use_underline">True</property>
+                        <property name="image">gtk-no-stock</property>
+                        <property name="use_stock">False</property>
+                        <property name="always_show_image">True</property>
+                        <signal name="activate" handler="gtkui_togglemore" swapped="no"/>
+                      </object>
+                    </child>
+                  </object>
+                </child>
+              </object>
+            </child>
+            <child>
+              <object class="GtkMenuItem">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="label" translatable="yes">_Help</property>
+                <property name="use_underline">True</property>
+                <child type="submenu">
+                  <object class="GtkMenu">
+                    <property name="visible">True</property>
+                    <property name="can_focus">False</property>
+                    <child>
+                      <object class="GtkImageMenuItem">
+                        <property name="label">gtk-about</property>
+                        <property name="visible">True</property>
+                        <property name="can_focus">False</property>
+                        <property name="use_underline">True</property>
+                        <property name="use_stock">True</property>
+                        <property name="always_show_image">True</property>
+                      </object>
+                    </child>
+                  </object>
+                </child>
+              </object>
+            </child>
           </object>
           <packing>
-            <property name="left_attach">2</property>
-            <property name="top_attach">2</property>
+            <property name="expand">False</property>
+            <property name="fill">True</property>
+            <property name="position">0</property>
           </packing>
         </child>
         <child>
-          <object class="GtkLabel" id="voltlabel">
+          <object class="GtkGrid">
             <property name="visible">True</property>
             <property name="can_focus">False</property>
-            <property name="label" translatable="yes"> Voltage: </property>
+            <child>
+              <object class="GtkLabel" id="ticker">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="margin_left">4</property>
+                <property name="margin_right">2</property>
+                <property name="margin_top">2</property>
+                <property name="margin_bottom">2</property>
+              </object>
+              <packing>
+                <property name="left_attach">0</property>
+                <property name="top_attach">0</property>
+              </packing>
+            </child>
+            <child>
+              <object class="GtkLabel">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="halign">end</property>
+                <property name="margin_left">2</property>
+                <property name="margin_right">2</property>
+                <property name="margin_top">2</property>
+                <property name="margin_bottom">2</property>
+                <property name="label" translatable="yes"> Temperature: </property>
+              </object>
+              <packing>
+                <property name="left_attach">1</property>
+                <property name="top_attach">0</property>
+              </packing>
+            </child>
+            <child>
+              <object class="GtkLabel" id="tempvalue">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="halign">start</property>
+                <property name="margin_left">2</property>
+                <property name="margin_right">2</property>
+                <property name="margin_top">2</property>
+                <property name="margin_bottom">2</property>
+              </object>
+              <packing>
+                <property name="left_attach">2</property>
+                <property name="top_attach">0</property>
+              </packing>
+            </child>
+            <child>
+              <object class="GtkLabel" id="reslabel">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="halign">end</property>
+                <property name="margin_left">2</property>
+                <property name="margin_right">2</property>
+                <property name="margin_top">2</property>
+                <property name="margin_bottom">2</property>
+                <property name="label" translatable="yes"> Resistence: </property>
+              </object>
+              <packing>
+                <property name="left_attach">1</property>
+                <property name="top_attach">1</property>
+              </packing>
+            </child>
+            <child>
+              <object class="GtkLabel" id="resistance">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="halign">start</property>
+                <property name="margin_left">2</property>
+                <property name="margin_right">2</property>
+                <property name="margin_top">2</property>
+                <property name="margin_bottom">2</property>
+              </object>
+              <packing>
+                <property name="left_attach">2</property>
+                <property name="top_attach">1</property>
+              </packing>
+            </child>
+            <child>
+              <object class="GtkLabel" id="voltage">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="halign">start</property>
+                <property name="margin_left">2</property>
+                <property name="margin_right">2</property>
+                <property name="margin_top">2</property>
+                <property name="margin_bottom">2</property>
+              </object>
+              <packing>
+                <property name="left_attach">2</property>
+                <property name="top_attach">2</property>
+              </packing>
+            </child>
+            <child>
+              <object class="GtkLabel" id="voltlabel">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="halign">end</property>
+                <property name="margin_left">2</property>
+                <property name="margin_right">2</property>
+                <property name="margin_top">2</property>
+                <property name="margin_bottom">2</property>
+                <property name="label" translatable="yes"> Voltage: </property>
+              </object>
+              <packing>
+                <property name="left_attach">1</property>
+                <property name="top_attach">2</property>
+              </packing>
+            </child>
+            <child>
+              <placeholder/>
+            </child>
+            <child>
+              <placeholder/>
+            </child>
           </object>
           <packing>
-            <property name="left_attach">1</property>
-            <property name="top_attach">2</property>
+            <property name="expand">False</property>
+            <property name="fill">True</property>
+            <property name="position">1</property>
           </packing>
         </child>
-        <child>
-          <placeholder/>
-        </child>
-        <child>
-          <placeholder/>
-        </child>
-        <child>
-          <placeholder/>
-        </child>
-        <child>
-          <placeholder/>
-        </child>
       </object>
     </child>
   </object>
diff --git a/src/server/gtklayout_flash.ui b/src/server/gtklayout_flash.ui
new file mode 100644
index 0000000..9972a4e
--- /dev/null
+++ b/src/server/gtklayout_flash.ui
@@ -0,0 +1,371 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!-- Generated with glade 3.20.0 -->
+<interface>
+  <requires lib="gtk+" version="3.20"/>
+  <object class="GtkImage" id="cancel">
+    <property name="visible">True</property>
+    <property name="can_focus">False</property>
+    <property name="stock">gtk-cancel</property>
+  </object>
+  <object class="GtkImage" id="ok">
+    <property name="visible">True</property>
+    <property name="can_focus">False</property>
+    <property name="stock">gtk-apply</property>
+  </object>
+  <object class="GtkWindow" id="flashwindow">
+    <property name="visible">True</property>
+    <property name="can_focus">False</property>
+    <property name="title" translatable="yes">coffeetemp – write flash</property>
+    <property name="resizable">False</property>
+    <property name="destroy_with_parent">True</property>
+    <child>
+      <object class="GtkGrid">
+        <property name="visible">True</property>
+        <property name="can_focus">False</property>
+        <signal name="destroy" handler="gtkui_flashwindow_clean" swapped="no"/>
+        <child>
+          <object class="GtkEntry" id="ssid_entry">
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="max_length">32</property>
+            <signal name="changed" handler="gtkui_readssid" swapped="no"/>
+          </object>
+          <packing>
+            <property name="left_attach">1</property>
+            <property name="top_attach">0</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkEntry" id="pass_entry">
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="max_length">32</property>
+            <property name="visibility">False</property>
+            <property name="input_purpose">password</property>
+            <signal name="changed" handler="gtkui_readpass" swapped="no"/>
+          </object>
+          <packing>
+            <property name="left_attach">1</property>
+            <property name="top_attach">1</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkEntry" id="htemp_entry">
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="max_length">6</property>
+            <property name="input_purpose">digits</property>
+            <signal name="changed" handler="gtkui_readhtemp" swapped="no"/>
+          </object>
+          <packing>
+            <property name="left_attach">1</property>
+            <property name="top_attach">2</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="halign">end</property>
+            <property name="margin_left">2</property>
+            <property name="margin_right">2</property>
+            <property name="margin_top">2</property>
+            <property name="margin_bottom">2</property>
+            <property name="label" translatable="yes">SSID:</property>
+          </object>
+          <packing>
+            <property name="left_attach">0</property>
+            <property name="top_attach">0</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="halign">end</property>
+            <property name="margin_left">2</property>
+            <property name="margin_right">2</property>
+            <property name="margin_top">2</property>
+            <property name="margin_bottom">2</property>
+            <property name="label" translatable="yes">Password:</property>
+          </object>
+          <packing>
+            <property name="left_attach">0</property>
+            <property name="top_attach">1</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="halign">end</property>
+            <property name="margin_left">2</property>
+            <property name="margin_right">2</property>
+            <property name="margin_top">2</property>
+            <property name="margin_bottom">2</property>
+            <property name="label" translatable="yes">High Temp:</property>
+          </object>
+          <packing>
+            <property name="left_attach">0</property>
+            <property name="top_attach">2</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="halign">end</property>
+            <property name="margin_left">2</property>
+            <property name="margin_right">2</property>
+            <property name="margin_top">2</property>
+            <property name="margin_bottom">2</property>
+            <property name="label" translatable="yes">Mid-high Temp:</property>
+          </object>
+          <packing>
+            <property name="left_attach">0</property>
+            <property name="top_attach">3</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkEntry" id="mhtemp_entry">
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="max_length">6</property>
+            <property name="input_purpose">digits</property>
+            <signal name="changed" handler="gtkui_readmhtemp" swapped="no"/>
+          </object>
+          <packing>
+            <property name="left_attach">1</property>
+            <property name="top_attach">3</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="halign">start</property>
+            <property name="margin_left">2</property>
+            <property name="margin_right">2</property>
+            <property name="margin_top">2</property>
+            <property name="margin_bottom">2</property>
+            <property name="label" translatable="yes">°C</property>
+          </object>
+          <packing>
+            <property name="left_attach">2</property>
+            <property name="top_attach">2</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="halign">start</property>
+            <property name="margin_left">2</property>
+            <property name="margin_right">2</property>
+            <property name="margin_top">2</property>
+            <property name="margin_bottom">2</property>
+            <property name="label" translatable="yes">°C</property>
+          </object>
+          <packing>
+            <property name="left_attach">2</property>
+            <property name="top_attach">3</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkButton" id="cancelbutton">
+            <property name="label" translatable="yes">Cancel</property>
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="receives_default">True</property>
+            <property name="image">cancel</property>
+            <signal name="clicked" handler="gtk_window_close" object="flashwindow" swapped="no"/>
+          </object>
+          <packing>
+            <property name="left_attach">0</property>
+            <property name="top_attach">6</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkButton" id="flashbutton">
+            <property name="label" translatable="yes">Write Flash</property>
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="receives_default">True</property>
+            <property name="image">ok</property>
+            <signal name="clicked" handler="gtkui_issue_flash_request" swapped="no"/>
+          </object>
+          <packing>
+            <property name="left_attach">1</property>
+            <property name="top_attach">6</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="halign">end</property>
+            <property name="margin_left">2</property>
+            <property name="margin_right">2</property>
+            <property name="margin_top">2</property>
+            <property name="margin_bottom">2</property>
+            <property name="label" translatable="yes">Low Temp:</property>
+          </object>
+          <packing>
+            <property name="left_attach">0</property>
+            <property name="top_attach">5</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkEntry" id="ltemp_entry">
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="max_length">6</property>
+            <property name="input_purpose">digits</property>
+            <signal name="changed" handler="gtkui_readltemp" swapped="no"/>
+          </object>
+          <packing>
+            <property name="left_attach">1</property>
+            <property name="top_attach">5</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="halign">start</property>
+            <property name="margin_left">2</property>
+            <property name="margin_right">2</property>
+            <property name="margin_top">2</property>
+            <property name="margin_bottom">2</property>
+            <property name="label" translatable="yes">°C</property>
+          </object>
+          <packing>
+            <property name="left_attach">2</property>
+            <property name="top_attach">4</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="halign">start</property>
+            <property name="margin_left">2</property>
+            <property name="margin_right">2</property>
+            <property name="margin_top">1</property>
+            <property name="margin_bottom">1</property>
+            <property name="label" translatable="yes">°C</property>
+          </object>
+          <packing>
+            <property name="left_attach">2</property>
+            <property name="top_attach">5</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="halign">end</property>
+            <property name="margin_left">2</property>
+            <property name="margin_right">2</property>
+            <property name="margin_top">1</property>
+            <property name="margin_bottom">1</property>
+            <property name="label" translatable="yes">Mid-low Temp:</property>
+          </object>
+          <packing>
+            <property name="left_attach">0</property>
+            <property name="top_attach">4</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkEntry" id="mltemp_entry">
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="max_length">6</property>
+            <property name="input_purpose">digits</property>
+            <signal name="changed" handler="gtkui_readmltemp" swapped="no"/>
+          </object>
+          <packing>
+            <property name="left_attach">1</property>
+            <property name="top_attach">4</property>
+          </packing>
+        </child>
+        <child>
+          <placeholder/>
+        </child>
+        <child>
+          <placeholder/>
+        </child>
+        <child>
+          <placeholder/>
+        </child>
+      </object>
+    </child>
+  </object>
+  <object class="GtkDialog" id="flashdialog">
+    <property name="can_focus">False</property>
+    <property name="title" translatable="yes">Flashing...</property>
+    <property name="resizable">False</property>
+    <property name="modal">True</property>
+    <property name="destroy_with_parent">True</property>
+    <property name="type_hint">dialog</property>
+    <property name="skip_taskbar_hint">True</property>
+    <property name="transient_for">flashwindow</property>
+    <property name="attached_to">flashwindow</property>
+    <signal name="close" handler="gtkui_manhandle_flashdialog" swapped="no"/>
+    <signal name="delete-event" handler="gtk_widget_hide_on_delete" swapped="no"/>
+    <child internal-child="vbox">
+      <object class="GtkBox">
+        <property name="visible">True</property>
+        <property name="can_focus">False</property>
+        <property name="orientation">vertical</property>
+        <property name="spacing">2</property>
+        <child internal-child="action_area">
+          <object class="GtkButtonBox">
+            <property name="can_focus">False</property>
+            <property name="layout_style">end</property>
+            <child>
+              <object class="GtkButton" id="dialog_ok">
+                <property name="label">gtk-ok</property>
+                <property name="visible">True</property>
+                <property name="sensitive">False</property>
+                <property name="can_focus">True</property>
+                <property name="receives_default">True</property>
+                <property name="use_stock">True</property>
+                <signal name="clicked" handler="gtkui_manhandle_flashdialog" object="flashdialog" swapped="yes"/>
+              </object>
+              <packing>
+                <property name="expand">True</property>
+                <property name="fill">True</property>
+                <property name="position">0</property>
+              </packing>
+            </child>
+          </object>
+          <packing>
+            <property name="expand">False</property>
+            <property name="fill">False</property>
+            <property name="position">2</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkLabel" id="dialog_text">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="halign">start</property>
+            <property name="margin_left">3</property>
+            <property name="margin_right">3</property>
+            <property name="margin_top">3</property>
+            <property name="margin_bottom">3</property>
+            <property name="hexpand">True</property>
+            <property name="label" translatable="yes">Writing to flash...     </property>
+            <property name="width_chars">25</property>
+          </object>
+          <packing>
+            <property name="expand">False</property>
+            <property name="fill">True</property>
+            <property name="position">0</property>
+          </packing>
+        </child>
+      </object>
+    </child>
+  </object>
+</interface>
diff --git a/src/server/meson.build b/src/server/meson.build
index c95f9a9..2b7af61 100644
--- a/src/server/meson.build
+++ b/src/server/meson.build
@@ -14,6 +14,7 @@ dp_filenames = [
 
 dp_extra_filenames = [
 	'gtklayout.ui',
+	'gtklayout_flash.ui',
 ]
 
 dp_sources = files(dp_filenames)
diff --git a/src/server/util.c b/src/server/util.c
index bb494c8..4aee886 100644
--- a/src/server/util.c
+++ b/src/server/util.c
@@ -18,12 +18,32 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  */
 
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <gtk/gtk.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <time.h>
+#include <endian.h>
 #include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
 #include "util.h"
 #include "net.h"
+#include "gtk.h"
+
+struct child_data {
+	char **argv;
+	int fd;
+	char *buf;
+};
 
 static float digest_temp(const short int rawtemp);
 static float digest_volt(const short int rawvolt);
+static int find_settings_region(char *start, char *end, char *buf, size_t n);
+static int flash(char *buf, size_t address, size_t size, char* port);
+void reap_dead_children(int pid, int status, void *data);
 
 /*
  * raw data is in 0.1°K per 1. Subtract 2730 to get Celsius.
@@ -57,3 +77,125 @@ int refresh_data(int nd, struct tempmodule_state *state)
 
 	return ret;
 }
+
+
+int write_settings(char *imagename, const struct configuration * const conf)
+{
+	/* the largest flash size supported by ESP-8266 is 16MiB, so let's just use that. */
+	static const size_t flash_size = 16 * 1024 * 1024;
+	char pattern_a[4] = PADDING_START;
+	char pattern_b[4] = PADDING_END;
+	ssize_t buf_used;
+	ssize_t offset;
+	char *buf = NULL;
+	int fd;
+	int ret = ERROR;
+
+	fd = open(imagename, O_RDONLY);
+	if (fd < 0) {
+		goto fail;
+	}
+	buf = malloc(flash_size);
+	buf_used = read(fd, buf, flash_size);
+	close(fd);
+	if (buf_used < sizeof(struct configuration)) {
+		goto fail;
+	}
+
+	offset = find_settings_region(pattern_a, pattern_b, buf, buf_used);
+	if (offset == ERROR) {
+		goto fail;
+	};
+
+	memcpy(buf + offset, conf, sizeof(struct configuration));
+	/* make sure the block written is aligned on 4k boundry
+	 * and is 4k of size.
+	 *
+	 * see:
+	 * https://github.com/espressif/esptool/issues/306
+	 */
+	offset &= ~(0xfff);
+	ret = flash(buf + offset, offset, 4 * 1024, NULL);
+
+fail:
+	free(buf);
+	return ret;
+}
+
+static int find_settings_region(char *start, char *end, char *buf, size_t n)
+{
+	int ret = ERROR;
+	char *a;
+
+	if (!(a = memmem(buf, n, start, 4))) {
+		goto fail;
+	}
+
+	if ((a - buf + sizeof(struct configuration)) > n) {
+		goto fail;
+	}
+
+	if (memcmp(a + sizeof(struct configuration) - 4, end, 4)) {
+		goto fail;
+	}
+
+	ret = a - buf;
+fail:
+	return ret;
+}
+
+static int flash(char *buf, size_t address, size_t size, char* port)
+{
+	static const char esptool[] = "esptool.py";
+	static const char command[] = "write_flash";
+	struct child_data *cdata;
+	char tmpfn[] = "espXXXXXX";	/* temporary file name template */
+	char *fifn;			/* flash image file name */
+	char textbuf[32];
+	char *argv[7] = {0};
+	int ret = ERROR;
+	pid_t pid;
+	int fd;
+	size_t i = 1;
+
+	fd = mkstemp(tmpfn);
+	write(fd, buf, size);
+	fifn = malloc(0x100);
+	memset(fifn, '\0', 0x100);
+	sprintf(textbuf, "/proc/self/fd/%d", fd);
+	if (readlink(textbuf, fifn, 0x100) == -1) {
+		exit(TMPFILE);
+	}
+
+	argv[0] = strdup(esptool);
+	if (port) {
+		argv[i++] = strdup("--port");
+		argv[i++] = strdup(port);
+	}
+	argv[i++] = strdup(command);
+	sprintf(textbuf, "%#.4lx", address);
+	argv[i++] = strdup(textbuf);
+	argv[i++] = strdup(fifn);
+	argv[i] = NULL;
+
+	cdata = malloc(sizeof(*cdata));
+	cdata->argv = argv;
+	cdata->fd = fd;
+	cdata->buf = fifn;
+
+	g_spawn_async_with_pipes(NULL, argv, NULL, G_SPAWN_SEARCH_PATH | G_SPAWN_LEAVE_DESCRIPTORS_OPEN | G_SPAWN_DO_NOT_REAP_CHILD, NULL, NULL, &pid, NULL, NULL, NULL, NULL);
+	g_child_watch_add(pid, reap_dead_children, cdata);
+	return ret;
+}
+
+void reap_dead_children(int pid, int status, void *data)
+{
+	struct child_data *a;
+
+	a = data;
+	free(a->buf);
+	close(a->fd);
+	free(data);
+	g_spawn_close_pid(pid);
+	gtkui_dialog_done(status);
+}
diff --git a/src/server/util.h b/src/server/util.h
index 9c0f907..ef5cde2 100644
--- a/src/server/util.h
+++ b/src/server/util.h
@@ -21,13 +21,17 @@
 #ifndef UTIL_H_INCLUDED
 #define UTIL_H_INCLUDED
 
+#include "datatypes.h"
+
 #define arrsize(a) (sizeof(a)/sizeof(*a))
 
 enum response {
 	ERROR = -1,
-	A_OK = 0,
-	NONEWDATA = 1,
-	DEAD = 2
+	A_OK = 0, /* would be "OK", but clashes with some lib definitions */
+	NONEWDATA,
+	DEAD,
+	NO_ESPTOOL,
+	TMPFILE,
 };
 
 struct tempmodule_state {
@@ -51,5 +55,6 @@ struct tempmodule_state {
 };
 
 int refresh_data(int nd, struct tempmodule_state *state);
+int write_settings(char *imagename, const struct configuration * const conf);
 
 #endif /* UTIL_H_INCLUDED */