Fix flash firing detection

Author: victoryforce

src/common/variables.c

@@ -106,6 +106,16 @@ typedef struct dt_variables_data_t
 
 static char *_expand_source(dt_variables_params_t *params, char **source, char extra_stop);
 
+static gboolean _is_flash_fired(const dt_image_t *img)
+{
+  if(g_strrstr(img->exif_flash, "did not fire"))
+    return FALSE;
+  if(img->exif_flash[0] == 'N')  // "No", that is no flash function present
+    return FALSE;
+  else
+    return TRUE;  // all other strings mean that the flash fired
+}
+
 // gather some data that might be used for variable expansion
 static void _init_expansion(dt_variables_params_t *params, gboolean iterate)
 {
@@ -180,8 +190,8 @@ static void _init_expansion(dt_variables_params_t *params, gboolean iterate)
     params->data->longitude = img->geoloc.longitude;
     params->data->latitude = img->geoloc.latitude;
     params->data->elevation = img->geoloc.elevation;
-    params->data->exif_flash_icon = img->exif_flash[0] == 'Y' ? "⚡" : "";
-    params->data->exif_flash = img->exif_flash[0] == 'Y' ? _("yes") : (img->exif_flash[0] == 'N' ? _("no") : _("n/a"));
+    params->data->exif_flash_icon = _is_flash_fired(img) ? "⚡" : "";
+    params->data->exif_flash = _is_flash_fired(img) ? _("yes") : _("no");
     params->data->exif_exposure_program = img->exif_exposure_program;
     params->data->exif_metering_mode = img->exif_metering_mode;
     params->data->exif_whitebalance = img->exif_whitebalance;