pixma: Restore old behaviour in case XML support is missing

Fixes #345.

backend/pixma/pixma_common.c

@@ -56,8 +56,6 @@
 
 #if defined(HAVE_LIBXML2)
 # include <libxml/parser.h>
-#else
-# error "The pixma backend requires libxml2"
 #endif
 
 #include "pixma_rename.h"
@@ -1241,6 +1239,7 @@ pixma_get_device_status (pixma_t * s, pixma_device_status_t * status)
   return s->ops->get_status (s, status);
 }
 
+#if defined(HAVE_LIBXML2)
 static const char *
 format_xml_response(const char *resp_details)
 {
@@ -1334,3 +1333,4 @@ clean:
   xmlFreeDoc(doc);
   return status;
 }
+#endif

backend/pixma/pixma_common.h

@@ -205,7 +205,9 @@ uint8_t *pixma_newcmd (pixma_cmdbuf_t *, unsigned cmd,
 int pixma_exec (pixma_t *, pixma_cmdbuf_t *);
 int pixma_exec_short_cmd (pixma_t *, pixma_cmdbuf_t *, unsigned cmd);
 int pixma_map_status_errno (unsigned status);
+#if defined(HAVE_LIBXML2)
 int pixma_parse_xml_response(const char *xml_message);
+#endif
 /**@}*/
 
 #define pixma_fill_checksum(start, end) do {		\

backend/pixma/pixma_mp150.c

@@ -322,6 +322,10 @@
 <ivec:param_set servicetype=\"scan\"><ivec:jobID>00000001</ivec:jobID>\
 </ivec:param_set></ivec:contents></cmd>"
 
+#if !defined(HAVE_LIBXML2)
+#define XML_OK   "<ivec:response>OK</ivec:response>"
+#endif
+
 enum mp150_state_t
 {
   state_idle,
@@ -459,7 +463,11 @@ send_xml_dialog (pixma_t * s, const char * xml_message)
   PDBG (pixma_dbg (10, "XML message sent to scanner:\n%s\n", xml_message));
   PDBG (pixma_dbg (10, "XML response back from scanner:\n%s\n", mp->cb.buf));
 
+#if defined(HAVE_LIBXML2)
   return pixma_parse_xml_response((const char*)mp->cb.buf) == PIXMA_STATUS_OK;
+#else
+  return (strcasestr ((const char *) mp->cb.buf, XML_OK) != NULL);
+#endif
 }
 
 static int

backend/pixma/pixma_mp800.c

@@ -152,6 +152,10 @@
 <ivec:param_set servicetype=\"scan\"><ivec:jobID>00000001</ivec:jobID>\
 </ivec:param_set></ivec:contents></cmd>"
 
+#if !defined(HAVE_LIBXML2)
+#define XML_OK   "<ivec:response>OK</ivec:response>"
+#endif
+
 enum mp810_state_t
 {
   state_idle,
@@ -291,7 +295,11 @@ static int send_xml_dialog (pixma_t * s, const char * xml_message)
   PDBG(pixma_dbg (10, "XML message sent to scanner:\n%s\n", xml_message));
   PDBG(pixma_dbg (10, "XML response back from scanner:\n%s\n", mp->cb.buf));
 
+#if defined(HAVE_LIBXML2)
   return pixma_parse_xml_response((const char*)mp->cb.buf) == PIXMA_STATUS_OK;
+#else
+  return (strcasestr ((const char *) mp->cb.buf, XML_OK) != NULL);
+#endif
 }
 
 static void new_cmd_tpu_msg (pixma_t *s, pixma_cmdbuf_t * cb, uint16_t cmd)