common: Re-add the libusb < 1.0.13 workarounds.

It comes with a GIANT WARNING if you are affected by the workaround.

README

@@ -93,7 +93,8 @@
  ***************************************************************************
   Compilation:
 
-     You will need libusb/libusbx v1.0.13 (or newer) to build this tool.
+     You will need libusb/libusbx 1.0 to build this tool.
+     We recommend v1.0.13 (or newer) for full functionality.
 
      Fedora/RedHat:
 	yum install libusbx-devel

backend_common.c

@@ -27,13 +27,14 @@
 
 #include "backend_common.h"
 
-#define BACKEND_VERSION "0.33"
+#define BACKEND_VERSION "0.34"
 #ifndef URI_PREFIX
 #error "Must Define URI_PREFIX"
 #endif
 
 #if !defined(LIBUSBX_API_VERSION) && !defined(LIBUSB_API_VERSION)
-#error "We need libusb >= 1.0.13!"
+#define OLDLIBUSB_WORKAROUND
+#warning "We HIGHLY recommend using libusb >= 1.0.13!"
 #endif
 
 /* Support Functions */
@@ -232,7 +233,13 @@ static int print_scan_output(struct libusb_device *device,
 		uint8_t port_num;
 
 		bus_num = libusb_get_bus_number(device);
+#ifdef OLDLIBUSB_WORKAROUND
+		WARNING("**** THIS PRINTER DOES NOT EXPORT A SERIAL NUMBER AND YOU ARE USING LIBUSB < 1.0.13\n");
+		WARNING("**** We cannot identify individual printers of this type without a newer version of libusb!\n");
+		port_num = 255;
+#else
 		port_num = libusb_get_port_number(device);
+#endif
 		sprintf((char*)serial, "NONE_B%03d_D%03d", bus_num, port_num);
 	}
 	

backend_common.h

@@ -45,6 +45,7 @@
 #define DEBUG( ... ) fprintf(stderr, "DEBUG: " __VA_ARGS__ )
 #define DEBUG2( ... ) fprintf(stderr, __VA_ARGS__ )
 #define INFO( ... )  fprintf(stderr, "INFO: " __VA_ARGS__ )
+#define WARNING( ... )  fprintf(stderr, "WARNING: " __VA_ARGS__ )
 #define ERROR( ... ) do { fprintf(stderr, "ERROR: " __VA_ARGS__ ); sleep(1); } while (0)
 
 #if (__BYTE_ORDER == __LITTLE_ENDIAN)