-#define CT_APPLICATION_JSON 1
-#define CT_TEXT_PLAIN 2
-#define CT_TEXT_HTML 3
-#define CT_APPLICATION_X_JAVASCRIPT 4
-#define CT_TEXT_CSS 5
-#define CT_TEXT_XML 6
-#define CT_APPLICATION_XML 7
-#define CT_TEXT_XSL 8
-#define CT_APPLICATION_OCTET_STREAM 9
-#define CT_APPLICATION_X_FONT_TRUETYPE 10
-#define CT_APPLICATION_X_FONT_OPENTYPE 11
-#define CT_APPLICATION_FONT_WOFF 12
-#define CT_APPLICATION_FONT_WOFF2 13
-#define CT_APPLICATION_VND_MS_FONTOBJ 14
-#define CT_IMAGE_SVG_XML 15
+#define CT_APPLICATION_JSON 1
+#define CT_TEXT_PLAIN 2
+#define CT_TEXT_HTML 3
+#define CT_APPLICATION_X_JAVASCRIPT 4
+#define CT_TEXT_CSS 5
+#define CT_TEXT_XML 6
+#define CT_APPLICATION_XML 7
+#define CT_TEXT_XSL 8
+#define CT_APPLICATION_OCTET_STREAM 9
+#define CT_APPLICATION_X_FONT_TRUETYPE 10
+#define CT_APPLICATION_X_FONT_OPENTYPE 11
+#define CT_APPLICATION_FONT_WOFF 12
+#define CT_APPLICATION_FONT_WOFF2 13
+#define CT_APPLICATION_VND_MS_FONTOBJ 14
+#define CT_IMAGE_SVG_XML 15
+#define CT_IMAGE_PNG 16
+#define CT_IMAGE_JPG 17
+#define CT_IMAGE_GIF 18
+#define CT_IMAGE_XICON 19
+#define CT_IMAGE_ICNS 20
+#define CT_IMAGE_BMP 21
+#define CT_PROMETHEUS 22
+
+#define buffer_cacheable(wb) do { (wb)->options |= WB_CONTENT_CACHEABLE; if((wb)->options & WB_CONTENT_NO_CACHEABLE) (wb)->options &= ~WB_CONTENT_NO_CACHEABLE; } while(0)
+#define buffer_no_cacheable(wb) do { (wb)->options |= WB_CONTENT_NO_CACHEABLE; if((wb)->options & WB_CONTENT_CACHEABLE) (wb)->options &= ~WB_CONTENT_CACHEABLE; (wb)->expires = 0; } while(0)