starting the hidapi USB device backend

Makefile.in

@@ -10,7 +10,7 @@ warn = -pedantic -Wall
 CC ?= gcc
 CFLAGS = $(warn) $(dbg) $(opt) -fno-strict-aliasing -fcommon \
 		 -I$(srcdir)/src -I/usr/local/include -MMD $(add_cflags)
-LDFLAGS = -L/usr/local/lib $(xlib) $(add_ldflags) -lm
+LDFLAGS = -L/usr/local/lib $(xlib) $(hidapi) $(add_ldflags) -lm
 
 $(bin): $(obj)
 	$(CC) -o $@ $(obj) $(LDFLAGS)

configure

@@ -141,6 +141,17 @@ HAVE_MALLOC_H=`check_header malloc.h`
 HAVE_STDINT_H=`check_header stdint.h`
 HAVE_INTTYPES_H=`check_header inttypes.h`
 
+#if [ `uname -s` != Linux ]; then
+	HAVE_HIDAPI_H=`check_header hidapi/hidapi.h`
+
+	if [ -z "$HAVE_HIDAPI_H" ]; then
+		echo "WARNING: without the hidapi library USB devices will not be \
+supported on this platform."
+		echo
+	fi
+#fi
+
+
 if [ "$X11" = "no" ]; then
 	echo "WARNING: you have disabled the X11 interface, the resulting daemon \
 won't be compatible with applications written for the proprietary 3Dconnexion \
@@ -181,6 +192,11 @@ if [ "$X11" = 'yes' ]; then
 	echo 'xlib += -lX11 -lXext' >>Makefile
 fi
 
+if [ -n "$HAVE_HIDAPI_H" ]; then
+	echo 'hidapi = -lhidapi-hidraw' >>Makefile
+	#echo 'hidapi = -lhidapi-libusb' >>Makefile
+fi
+
 if [ -n "$CFLAGS" ]; then
 	echo "add_cflags = $CFLAGS" >>Makefile
 fi
@@ -206,6 +222,10 @@ if [ "$HOTPLUG" = yes ]; then
 	echo '#define USE_NETLINK' >>$cfgheader
 	echo >>$cfgheader
 fi
+if [ -n "$HAVE_HIDAPI_H" ]; then
+	echo '#define USE_HIDAPI' >>$cfgheader
+	echo >>$cfgheader
+fi
 echo '#define VERSION "'$VER'"' >>$cfgheader
 echo >>$cfgheader
 
@@ -216,6 +236,7 @@ echo >>$cfgheader
 [ -n "$HAVE_INTTYPES_H" ] && echo $HAVE_INTTYPES_H >>$cfgheader
 [ -n "$HAVE_XINPUT2_H" ] && echo $HAVE_XINPUT2_H >>$cfgheader
 [ -n "$HAVE_XTEST_H" ] && echo $HAVE_XTEST_H >>$cfgheader
+[ -n "$HAVE_HIDAPI_H" ] && echo $HAVE_HIDAPI_H >>$cfgheader
 echo >>$cfgheader
 
 echo "#define CFGDIR \"$CFGDIR\"" >>$cfgheader

src/dev_usb_hidapi.c

@@ -0,0 +1,98 @@
+/*
+spacenavd - a free software replacement driver for 6dof space-mice.
+Copyright (C) 2007-2023 John Tsiombikas <nuclear@member.fsf.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+#include "config.h"
+
+#ifdef USE_HIDAPI
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <hidapi/hidapi.h>
+#include "dev.h"
+#include "dev_usb.h"
+#include "spnavd.h"
+#include "event.h"
+#include "hotplug.h"
+#include "client.h"
+
+
+int open_dev_usb(struct device *dev)
+{
+	return -1;
+}
+
+struct usb_dev_info *find_usb_devices(int (*match)(const struct usb_dev_info*))
+{
+	int len;
+	struct hid_device_info *hidlist, *hid;
+	struct usb_dev_info *dev, *devlist = 0;
+
+	if(!(hidlist = hid_enumerate(0, 0))) {
+		return 0;
+	}
+
+	hid = hidlist;
+	while(hid) {
+		if(!(dev = malloc(sizeof *dev))) {
+			fprintf(stderr, "failed to allocate device list node\n");
+			hid = hid->next;
+			continue;
+		}
+
+		len = wcslen(hid->product_string) + 1;
+		if(!(dev->name = malloc(len + 1))) {
+			fprintf(stderr, "failed to allocate buffer for device name\n");
+			free(dev);
+			hid = hid->next;
+			continue;
+		}
+		sprintf(dev->name, "%ls", hid->product_string);
+
+		dev->num_devfiles = 1;
+		if(!(dev->devfiles[0] = strdup(hid->path))) {
+			fprintf(stderr, "failed to allocate buffer for device path\n");
+			free(dev->name);
+			free(dev);
+			hid = hid->next;
+			continue;
+		}
+
+		dev->vendorid = hid->vendor_id;
+		dev->productid = hid->product_id;
+
+		/* check with the user-supplied matching callback to see if we should include
+		 * this device in the returned list or not...
+		 */
+		if(!match || match(dev)) {
+			printf("DBG %x:%x %s (%x,%x) - %s\n", dev->vendorid, dev->productid, dev->devfiles[0],
+					hid->usage_page, hid->usage, dev->name);
+			/*dev->next = devlist;
+			devlist = dev;*/
+		} else {
+			free(dev->name);
+			free(dev->devfiles[0]);
+			free(dev);
+		}
+
+		hid = hid->next;
+	}
+
+	hid_free_enumeration(hidlist);
+	return devlist;
+}
+
+#endif

src/dev_usb_linux.c

@@ -15,9 +15,10 @@ GNU General Public License for more details.
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
-#ifdef __linux__
-
 #include "config.h"
+
+#if defined(__linux__) && !defined(USE_HIDAPI)
+
 #include <stdio.h>
 #include <string.h>
 #include <errno.h>