1 files changed, 87 insertions, 0 deletions
diff --git a/lib/device.js b/lib/device.js
new file mode 100644
index 0000000..a9fb71d
--- /dev/null
+++ b/lib/device.js
@@ -0,0 +1,87 @@
+const fs = require("fs")
+    , util = require("util")
+    , EventEmitter = require("events").EventEmitter
+    , {eviocgrab, eviocgid} = require("bindings")("ioctl.node")
+    , events = require("./events");
+
+const arch = (process.arch.indexOf("64")>=0)?64:32;
+
+function Device(path) {
+  this.grabbed = false;
+  if (path) this.open(path);
+}
+
+util.inherits(Device, EventEmitter);
+
+Device.prototype.open = function(path) {
+  this.stream = fs
+    .createReadStream(path, {flags: "r", autoClose: true})
+    .on("error", e => this.emit("error", e))
+    .on("open", fd => { this.fd = fd;
+      try { this.id = eviocgid(fd); }
+      catch(e) { this.emit("error",
+        new Error("Reader eviocgid error:"+e)); }
+      if (this.grabbed) eviocgrab(this.fd, 1);
+      this.emit("open", fd); })
+    .on("data", buf => {
+      var i, j, chunk = (arch===64)?24:16;
+      for (i=0, j=buf.length; i<j; i+=chunk) {
+        const e = parse(buf.slice(i, i+chunk));
+        this.emit("event", e);
+        this.emit(e.type, e);
+      }});
+};
+
+Device.prototype.close = function() {
+  this.grabbed = false;
+  this.stream.close();
+  delete this.stream;
+  delete this.fd;
+  delete this.id;
+};
+
+Device.prototype.grab = function() {
+  if (this.grabbed) return; this.grabbed = true;
+  if (this.fd) eviocgrab(this.fd, 1);
+};
+
+Device.prototype.ungrab = function() {
+  if (!this.grabbed) return; this.grabbed = false;
+  if (this.fd) eviocgrab(this.fd, 0);
+};
+
+// struct input_event {
+//   struct timeval {
+//     long tv_sec;  // s32/64 (arch)
+//     long tv_usec; // LE (always?)
+//   } time;
+//   __u16 type;
+//   __u16 code;
+//   __s32 value;
+// };
+function parse(buf) {
+  var e = {time: {sec: null, usec: null},
+    type: null, code: null, value: null};
+
+  var offset;
+  if (arch === 64) { offset = 16;
+    e.time.sec  = buf.readBigInt64LE(0);
+    e.time.usec = buf.readBigInt64LE(8);
+  } else { offset = 8;
+    e.time.sec  = buf.readInt32LE(0);
+    e.time.usec = buf.readInt32LE(4);
+  }
+
+  e.type = buf.readUInt16LE(offset);
+  e.code = buf.readUInt16LE(offset + 2);
+  e.value = buf.readInt32LE(offset + 4);
+
+  if (events.types[e.type])
+    e.type = events.types[e.type];
+  if (events[e.type] && events[e.type][e.code])
+    e.code = events[e.type][e.code];
+
+  return e;
+};
+
+module.exports = Device;