usbip: tools: add more error codes for usbip request/reply messages

Currently ST_OK and ST_NA are the only values defined to communicate
status of a request from a client. Add more error codes to clearly
indicate what failed. For example, when client sends request to import
a device that isn't export-able, server can send a specific error code
to the client.

Existing defines are moved to a common header in libsrc to be included
in the libusbip_la-usbip_common.o to be used by all the usbip tools.
Supporting interface to print error strings is added to the common lib.

Signed-off-by: Shuah Khan <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

tools/usb/usbip/libsrc/usbip_common.c

···
 	return "Unknown Speed";
 }
 
+struct op_common_status_string {
+	int num;
+	char *desc;
+};
+
+static struct op_common_status_string op_common_status_strings[] = {
+	{ ST_OK,	"Request Completed Successfully" },
+	{ ST_NA,	"Request Failed" },
+	{ ST_DEV_BUSY,	"Device busy (exported)" },
+	{ ST_DEV_ERR,	"Device in error state" },
+	{ ST_NODEV,	"Device not found" },
+	{ ST_ERROR,	"Unexpected response" },
+	{ 0, NULL}
+};
+
+const char *usbip_op_common_status_string(int status)
+{
+	for (int i = 0; op_common_status_strings[i].desc != NULL; i++)
+		if (op_common_status_strings[i].num == status)
+			return op_common_status_strings[i].desc;
+
+	return "Unknown Op Common Status";
+}
 
 #define DBG_UDEV_INTEGER(name)\
 	dbg("%-20s = %x", to_string(name), (int) udev->name)

tools/usb/usbip/libsrc/usbip_common.h

···
 #define SYSFS_PATH_MAX		256
 #define SYSFS_BUS_ID_SIZE	32
 
+/* Defines for op_code status in server/client op_common PDUs */
+#define ST_OK	0x00
+#define ST_NA	0x01
+	/* Device requested for import is not available */
+#define ST_DEV_BUSY	0x02
+	/* Device requested for import is in error state */
+#define ST_DEV_ERR	0x03
+#define ST_NODEV	0x04
+#define ST_ERROR	0x05
+
 extern int usbip_use_syslog;
 extern int usbip_use_stderr;
 extern int usbip_use_debug ;
···
 
 const char *usbip_speed_string(int num);
 const char *usbip_status_string(int32_t status);
+const char *usbip_op_common_status_string(int status);
 
 int usbip_names_init(char *);
 void usbip_names_free(void);

tools/usb/usbip/src/usbip_network.h

···
 #define OP_REPLY	(0x00 << 8)
 	uint16_t code;
 
-	/* add more error code */
-#define ST_OK	0x00
-#define ST_NA	0x01
+	/* status codes defined in usbip_common.h */
 	uint32_t status; /* op_code status (for reply) */
 
 } __attribute__((packed));