Finding use of Java's Unsafe memory access

[Robert Dyer]

Inspired by this upcoming paper at SPLASH'15 (http://2015.splashcon.org/event/oopsla2015-use-at-your-own-risk-the-java-unsafe-api-in-the-wild) I wrote this query to find use of Unsafe in Java.

http://boa.cs.iastate.edu/boa/?q=boa/job/public/10150

# what projects use sun.misc.Unsafe in Java?
UnsafeProjects: output set of string;

# imports of sun.misc.Unsafe
UnsafeImport: output sum[string] of int;
# uses of sun.misc.Unsafe type
UnsafeType: output sum[string] of int;
# uses of Unsafe.getUnsafe() static method call
GetUnsafe: output sum[string] of int;

imported := false;

visit(input, visitor {
 before node: CodeRepository -> {
  # only look at the latest snapshot
  # and only include Java files
  snapshot := getsnapshot(node, "SOURCE_JAVA_JLS");
  foreach (i: int; def(snapshot[i]))
   visit(snapshot[i]);
  stop;
 }
 before node: ASTRoot -> {
  imported = false;
  exists (i: int; node.imports[i] == "sun.misc.Unsafe" || node.imports[i] == "sun.misc.*") {
   UnsafeImport[input.id] << 1;
   UnsafeProjects << input.id;
   imported = true;
  }
 }
 before node: Type ->
  if (node.name == "sun.misc.Unsafe" || (node.name == "Unsafe" && imported)) {
   UnsafeType[input.id] << 1;
   UnsafeProjects << input.id;
  }
 before node: Expression ->
  if (node.kind == ExpressionKind.METHODCALL && node.method == "getUnsafe") {
   GetUnsafe[input.id] << 1;
   UnsafeProjects << input.id;
  }
});