update socials section

node_modules/pidtree/lib/pidtree.js

@@ -0,0 +1,104 @@
+'use strict';
+
+var getAll = require('./get');
+
+/**
+ * Get the list of children and grandchildren pids of the given PID.
+ * @param  {Number|String} PID A PID. If -1 will return all the pids.
+ * @param  {Object} [options] Optional options object.
+ * @param  {Boolean} [options.root=false] Include the provided PID in the list.
+ * @param  {Boolean} [options.advanced=false] Returns a list of objects in the
+ * format {pid: X, ppid: Y}.
+ * @param  {Function} callback(err, list) Called when the list is ready.
+ */
+function list(PID, options, callback) {
+  if (typeof options === 'function') {
+    callback = options;
+    options = {};
+  }
+
+  if (typeof options !== 'object') {
+    options = {};
+  }
+
+  PID = parseInt(PID, 10);
+  if (isNaN(PID) || PID < -1) {
+    callback(new TypeError('The pid provided is invalid'));
+    return;
+  }
+
+  getAll(function(err, list) {
+    if (err) {
+      callback(err);
+      return;
+    }
+
+    // If the user wants the whole list just return it
+    if (PID === -1) {
+      for (var i = 0; i < list.length; i++) {
+        list[i] = options.advanced
+          ? {ppid: list[i][0], pid: list[i][1]}
+          : (list[i] = list[i][1]);
+      }
+
+      callback(null, list);
+      return;
+    }
+
+    var root;
+    for (var l = 0; l < list.length; l++) {
+      if (list[l][1] === PID) {
+        root = options.advanced ? {ppid: list[l][0], pid: PID} : PID;
+        break;
+      }
+
+      if (list[l][0] === PID) {
+        root = options.advanced ? {pid: PID} : PID; // Special pids like 0 on *nix
+      }
+    }
+
+    if (!root) {
+      callback(new Error('No matching pid found'));
+      return;
+    }
+
+    // Build the adiacency Hash Map (pid -> [children of pid])
+    var tree = {};
+    while (list.length > 0) {
+      var element = list.pop();
+      if (tree[element[0]]) {
+        tree[element[0]].push(element[1]);
+      } else {
+        tree[element[0]] = [element[1]];
+      }
+    }
+
+    // Starting by the PID provided by the user, traverse the tree using the
+    // adiacency Hash Map until the whole subtree is visited.
+    // Each pid encountered while visiting is added to the pids array.
+    var idx = 0;
+    var pids = [root];
+    while (idx < pids.length) {
+      var curpid = options.advanced ? pids[idx++].pid : pids[idx++];
+      if (!tree[curpid]) continue;
+      var length = tree[curpid].length;
+      for (var j = 0; j < length; j++) {
+        pids.push(
+          options.advanced
+            ? {ppid: curpid, pid: tree[curpid][j]}
+            : tree[curpid][j]
+        );
+      }
+
+      delete tree[curpid];
+    }
+
+    if (!options.root) {
+      pids.shift(); // Remove root
+    }
+
+    callback(null, pids);
+  });
+}
+
+module.exports = list;