Starting to turn relabsd into a proper daemon...

1 files changed, 272 insertions, 0 deletions

diff --git a/src/device/virtual_device.c b/src/device/virtual_device.c
new file mode 100644
index 0000000..19d1097
--- /dev/null
+++ b/src/device/virtual_device.c
@@ -0,0 +1,272 @@
+
+
+static void replace_rel_axes
+(
+   struct relabsd_virtual_device * const dev,
+   const struct relabsd_config * const config
+)
+{
+   int i;
+   struct input_absinfo absinfo;
+   unsigned int abs_code, rel_code;
+
+   for (i = RELABSD_VALID_AXES_COUNT; i --> 0;)
+   {
+      if (config->axis[i].enabled)
+      {
+         rel_code = relabsd_axis_to_rel((enum relabsd_axis) i);
+         abs_code = relabsd_axis_to_abs((enum relabsd_axis) i);
+
+         relabsd_config_get_absinfo(config, (enum relabsd_axis) i, &absinfo);
+         libevdev_disable_event_code(dev->dev, EV_REL, rel_code);
+         libevdev_enable_event_code(dev->dev, EV_ABS, abs_code, &absinfo);
+      }
+   }
+
+}
+
+static int rename_device
+(
+   struct libevdev * const dev,
+   const struct relabsd_config * const config
+)
+{
+   size_t new_name_size;
+   char * new_name;
+   const char * real_name;
+
+   /* +2: One for the \0, one for the space between prefix and 'real_name'. */
+   new_name_size = strlen(RELABSD_DEVICE_PREFIX) + 2;
+
+   if (config->device_name == (char *) NULL)
+   {
+      /* XXX
+       * "The name is never NULL but it may be the empty string."
+       * I'm assuming that since they use the term 'string', it is \0
+       * terminated.
+       */
+      real_name = libevdev_get_name(dev);
+   }
+   else
+   {
+      real_name = config->device_name;
+   }
+
+   new_name_size += strlen(real_name);
+
+   new_name = (char *) calloc(new_name_size, sizeof(char));
+
+   if (new_name == (char *) NULL)
+   {
+      RELABSD_ERROR
+      (
+         "Attempt at allocating memory to create the virtual device's name "
+         "failed: %s.",
+         strerror(errno)
+      );
+
+      /* This frees whatever came from 'libevdev_get_name'. */
+      libevdev_set_name(dev, RELABSD_DEVICE_PREFIX);
+
+      return -1;
+   }
+
+   if
+   (
+      snprintf
+      (
+         new_name,
+         new_name_size,
+         "%s %s",
+         RELABSD_DEVICE_PREFIX,
+         real_name
+      )
+      != ((int) (new_name_size - 1))
+   )
+   {
+      /* This makes for a great message when strerror(errno) returns SUCCESS. */
+      RELABSD_ERROR
+      (
+         "Something unexpected happened while renaming the virtual device: %s.",
+         strerror(errno)
+      );
+
+      /* This frees whatever came from 'libevdev_get_name'. */
+      libevdev_set_name(dev, RELABSD_DEVICE_PREFIX);
+
+      free((void *) new_name);
+
+      return -1;
+   }
+
+   /* This frees whatever came from 'libevdev_get_name'. */
+   libevdev_set_name(dev, new_name);
+   free((void *) new_name);
+
+   return 0;
+}
+
+int relabsd_virtual_device_create
+(
+   struct relabsd_virtual_device * const dev,
+   const struct relabsd_config * const config
+)
+{
+   int fd;
+
+   RELABSD_S_DEBUG(RELABSD_DEBUG_PROGRAM_FLOW, "Creating virtual device...");
+
+   fd = open(config->input_file, O_RDONLY);
+
+   if (fd < 0)
+   {
+      RELABSD_FATAL
+      (
+         "Could not open device '%s' in read only mode: %s.",
+         config->input_file,
+         strerror(errno)
+      );
+
+      return -1;
+   }
+
+   if (libevdev_new_from_fd(fd, &(dev->dev)) < 0)
+   {
+      RELABSD_FATAL
+      (
+         "libevdev could not open '%s': '%s'.",
+         config->input_file,
+         strerror(errno)
+      );
+
+      close(fd);
+
+      return -1;
+   }
+
+   if (rename_device(dev->dev, config) < 0)
+   {
+      libevdev_free(dev->dev);
+      close(fd);
+
+      return -1;
+   }
+
+   libevdev_enable_event_type(dev->dev, EV_ABS);
+
+   replace_rel_axes(dev, config);
+
+   if
+   (
+       libevdev_uinput_create_from_device
+       (
+         dev->dev,
+         /* See top of the file. */
+         RELABSD_UINPUT_OPEN_MANAGED,
+         &(dev->uidev)
+       )
+       < 0
+   )
+   {
+      RELABSD_FATAL("Could not create relabsd device: %s.", strerror(errno));
+
+      libevdev_free(dev->dev);
+
+      close(fd);
+
+      return -1;
+   }
+
+   close(fd);
+
+   return 0;
+}
+
+void relabsd_virtual_device_destroy (const struct relabsd_virtual_device * const dev)
+{
+   RELABSD_S_DEBUG(RELABSD_DEBUG_PROGRAM_FLOW, "Destroying virtual device...");
+
+   libevdev_uinput_destroy(dev->uidev);
+   libevdev_free(dev->dev);
+}
+
+int relabsd_virtual_device_write_evdev_event
+(
+   const struct relabsd_virtual_device * const dev,
+   unsigned int const type,
+   unsigned int const code,
+   int const value
+)
+{
+   RELABSD_DEBUG
+   (
+      RELABSD_DEBUG_VIRTUAL_EVENTS,
+      "Sending event: {type = %s; code = %s; value = %d}.",
+       libevdev_event_type_get_name(type),
+       libevdev_event_code_get_name(type, code),
+       value
+   );
+
+   /*
+    * We'll also send the 'EV_SYN' events when we receive them from the input
+    * device.
+    * OPTIMIZE: prevent 'EV_SYN' from being sent if we haven't sent any new
+    *           values. (It might not be worth it though)
+    */
+   if (libevdev_uinput_write_event(dev->uidev, type, code, value) == 0)
+   {
+      /* FIXME:
+       * Why does activating the timeout trigger the EV_KEYS event to not be
+       * followed by EV_SYN?
+       */
+      if (type == EV_KEY)
+      {
+         libevdev_uinput_write_event
+         (
+            dev->uidev,
+            EV_SYN,
+            SYN_REPORT,
+            0
+         );
+      }
+
+      return 0;
+   }
+
+   return -1;
+}
+
+void relabsd_virtual_device_set_axes_to_zero
+(
+   const struct relabsd_virtual_device * const dev,
+   const struct relabsd_config * const config
+)
+{
+   int i;
+
+   for (i = 0; i < RELABSD_VALID_AXES_COUNT; ++i)
+   {
+      if (config->axis[i].enabled)
+      {
+         relabsd_virtual_device_write_evdev_event
+         (
+            dev,
+            EV_ABS,
+            relabsd_axis_to_abs((enum relabsd_axis) i),
+            0
+         );
+      }
+   }
+
+   /*
+    * Also send a SYN event when the axes have been modified.
+    */
+   libevdev_uinput_write_event
+   (
+      dev->uidev,
+      EV_SYN,
+      SYN_REPORT,
+      0
+   );
+}
+