Use pkg-config for libusb

configure.ac

@@ -5,23 +5,14 @@ AC_PROG_CC
 AM_PROG_AR
 AM_PATH_PYTHON([2.6])
 LT_INIT
+PKG_PROG_PKG_CONFIG
 
 # Check for libusb-1.0
-AC_SEARCH_LIBS([libusb_init], [usb-1.0], [have_libusb=yes])
+PKG_CHECK_MODULES([LIBUSB], [libusb-1.0])
 
-AS_IF([test "x${have_libusb}" = xyes], [
-    AC_CHECK_HEADERS([libusb-1.0/libusb.h], [], [have_libusb=no])
-])
-
-AS_IF([test "x${have_libusb}" != xyes], [
-    AC_MSG_ERROR([
-    -------------------------------------------------------
-     The library libusb-1.0 and header file libusb.h
-     are required to build x52pro-linux. Stopping...
-     Check 'config.log' for more information.
-    -------------------------------------------------------
-    ])
-])
+AC_SUBST([LIBUSB_CFLAGS])
+AC_SUBST([LIBUSB_LDFLAGS])
+AC_SUBST([LIBUSB_LIBS])
 
 AC_SUBST([X52_PKG_VERSION], [0.1])
 AC_SUBST([X52_INCLUDE], ["-I \$(top_srcdir)/lib/libx52"])

lib/libusbx52/Makefile.am

@@ -4,15 +4,17 @@ ACLOCAL_AMFLAGS = -I m4
 check_LTLIBRARIES = libusbx52.la
 
 libusbx52_la_SOURCES = usb_x52_stub.c
+libusbx52_la_CFLAGS = @LIBUSB_CFLAGS@
 libusbx52_la_LDFLAGS = -rpath /nowhere -module
 
 # Utility programs for use by tests
 check_PROGRAMS = x52test_create_device_list x52test_log_actions
 
 x52test_create_device_list_SOURCES = util/create_device_list.c
+x52test_create_device_list_CFLAGS = @LIBUSB_CFLAGS@
 
 x52test_log_actions_SOURCES = util/log_actions.c
-x52test_log_actions_CFLAGS = @X52_INCLUDE@
+x52test_log_actions_CFLAGS = @X52_INCLUDE@ @LIBUSB_CFLAGS@
 x52test_log_actions_LDADD = libusbx52.la
 
 EXTRA_DIST = README.md libusbx52.h

lib/libusbx52/libusbx52.h

@@ -10,7 +10,8 @@
  */
 
 #include <stdio.h>
-#include <libusb-1.0/libusb.h>
+// #include <libusb-1.0/libusb.h>
+#include <libusb.h>
 
 struct libusb_device {
     struct libusb_context *context;

lib/libusbx52/usb_x52_stub.c

@@ -11,7 +11,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
-#include <libusb-1.0/libusb.h>
+#include <libusb.h>
 #include "libusbx52.h"
 
 int libusb_init(libusb_context **ctx)

lib/libx52/Makefile.am

@@ -6,7 +6,8 @@ lib_LTLIBRARIES = libx52.la
 # This library handles the USB communication between the host and the X52
 libx52_la_SOURCES = x52_control.c x52_core.c x52_date_time.c x52_mfd_led.c \
 					x52_strerror.c
-libx52_la_LDFLAGS = -version-info 3:0:1 -lusb-1.0
+libx52_la_CFLAGS = @LIBUSB_CFLAGS@
+libx52_la_LDFLAGS = -version-info 3:0:1 @LIBUSB_LIBS@
 
 # Header files that need to be copied
 x52includedir = $(includedir)/x52pro

lib/libx52/x52_common.h

@@ -14,7 +14,7 @@
 
 #include <stdint.h>
 #include <stdlib.h>
-#include <libusb-1.0/libusb.h>
+#include <libusb.h>
 #include "libx52.h"
 
 /*