input_id: code cleanup

Now use libudev to clean up hardcoded /sys/ and /device/ paths, and to also
support direct input device arguments. Now both "input4" and "event4" will
work.

diff --git a/Makefile.am b/Makefile.am
index 994092775b8563b895e77ad11ed90052e2053053..cd27f6f2d0fcde797b2945699f5b23355e8eba04 100644 (file)
--- a/Makefile.am
+++ b/Makefile.am
@@ -237,9 +237,10 @@ extras_floppy_create_floppy_devices_LDADD = libudev/libudev-private.la
 libexec_PROGRAMS += extras/floppy/create_floppy_devices
 
 # ------------------------------------------------------------------------------
-# usb_id - USB device property import
+# input_id - import input device class
 # ------------------------------------------------------------------------------
 extras_input_id_input_id_SOURCES = extras/input_id/input_id.c
+extras_input_id_input_id_LDADD = libudev/libudev.la
 libexec_PROGRAMS += extras/input_id/input_id
 
 # ------------------------------------------------------------------------------

diff --git a/extras/input_id/input_id.c b/extras/input_id/input_id.c
index 2e143a5628ccc508fc5baf8b6383e8f1e7f188b3..3754cdefee2faf6bbeaae2597c2d1b834fa6c0e8 100644 (file)
--- a/extras/input_id/input_id.c
+++ b/extras/input_id/input_id.c
@@ -25,6 +25,8 @@
 #include <limits.h>
 #include <linux/input.h>
 
+#include "libudev.h"
+
 /* we must use this kernel-compatible implementation */
 #define BITS_PER_LONG (sizeof(unsigned long) * 8)
 #define NBITS(x) ((((x)-1)/BITS_PER_LONG)+1)
@@ -34,29 +36,21 @@
 #define test_bit(bit, array)    ((array[LONG(bit)] >> OFF(bit)) & 1)
 
 /* 
- * Read a capabilities/name file and return bitmask.
- * @param path File to open
+ * Read a capability attribute and return bitmask.
+ * @param dev udev_device
+ * @param attr sysfs attribute name (e. g. "capabilities/key")
  * @param bitmask: Output array; must have max_size elements
  */
-static void get_cap_mask (const char *path, unsigned long *bitmask, size_t max_size)
+static void get_cap_mask (struct udev_device *dev, const char* attr,
+                         unsigned long *bitmask, size_t max_size)
 {
-       FILE* f;
-        int i;
        char text[4096];
+        int i;
        char* word;
        unsigned long val;
 
-       f = fopen(path, "r");
-       if (f == NULL) {
-               perror("opening caps file");
-               exit(1);
-       }
-       if (fgets(text, sizeof(text), f) == NULL) {
-               perror("fgets");
-               exit(1);
-       }
-       fclose(f);
-       
+       snprintf(text, sizeof(text), "%s", udev_device_get_sysattr_value(dev, attr));
+
         memset (bitmask, 0, max_size);
        i = 0;
         while ((word = strrchr(text, ' ')) != NULL) {
@@ -122,7 +116,10 @@ static void test_key (const unsigned long* bitmask_key)
 
 int main (int argc, char** argv)
 {
-       char capfile[PATH_MAX];
+       struct udev *udev;
+       struct udev_device *dev;
+
+       char devpath[PATH_MAX];
        unsigned long bitmask_abs[NBITS(ABS_MAX)];
        unsigned long bitmask_key[NBITS(KEY_MAX)];
         unsigned long bitmask_rel[NBITS(REL_MAX)];
@@ -132,16 +129,30 @@ int main (int argc, char** argv)
                exit(1);
        }
 
+       /* get the device */
+       udev = udev_new();
+       if (udev == NULL)
+               return 1;
+
+       snprintf(devpath, sizeof(devpath), "%s/%s", udev_get_sys_path(udev), argv[1]);
+       dev = udev_device_new_from_syspath(udev, devpath);
+       if (dev == NULL) {
+               fprintf(stderr, "unable to access '%s'\n", devpath);
+               return 1;
+       }
+
+       /* walk up the parental chain until we find the real input device; the
+        * argument is very likely a subdevice of this, like eventN */
+       while (udev_device_get_sysattr_value(dev, "capabilities/key") == NULL)
+               dev = udev_device_get_parent(dev);
+
        /* Use this as a flag that input devices were detected, so that this
         * program doesn't need to be called more than once per device */
        puts("ID_INPUT=1");
 
-       snprintf(capfile, sizeof(capfile), "/sys/%s/device/capabilities/abs", argv[1]);
-       get_cap_mask (capfile, bitmask_abs, sizeof (bitmask_abs));
-       snprintf(capfile, sizeof(capfile), "/sys/%s/device/capabilities/rel", argv[1]);
-       get_cap_mask (capfile, bitmask_rel, sizeof (bitmask_rel));
-       snprintf(capfile, sizeof(capfile), "/sys/%s/device/capabilities/key", argv[1]);
-       get_cap_mask (capfile, bitmask_key, sizeof (bitmask_key));
+       get_cap_mask (dev, "capabilities/abs", bitmask_abs, sizeof (bitmask_abs));
+       get_cap_mask (dev, "capabilities/rel", bitmask_rel, sizeof (bitmask_rel));
+       get_cap_mask (dev, "capabilities/key", bitmask_key, sizeof (bitmask_key));
 
        test_pointers(bitmask_abs, bitmask_key, bitmask_rel);