From 45690338b8cf73171b8b6eef9749bd328bda6f37 Mon Sep 17 00:00:00 2001
From: Calum Grant <calumgrant@github.com>
Date: Tue, 23 Apr 2024 13:00:01 +0100
Subject: [PATCH] Refactoring queries WIP

---
 .../src/experimental/refactoring/cstrings.ql  | 20 +++++++++++++++
 .../refactoring/fn_missing_namespace.ql       |  9 +++++++
 .../refactoring/fn_should_be_method.ql        |  4 +++
 .../refactoring/global_variables.ql           | 25 +++++++++++++++++++
 cpp/ql/src/experimental/refactoring/printf.ql |  7 ++++++
 .../src/experimental/refactoring/relevant.qll |  6 +++++
 .../refactoring/write_to_stream.ql            | 25 +++++++++++++++++++
 7 files changed, 96 insertions(+)
 create mode 100644 cpp/ql/src/experimental/refactoring/cstrings.ql
 create mode 100644 cpp/ql/src/experimental/refactoring/fn_missing_namespace.ql
 create mode 100644 cpp/ql/src/experimental/refactoring/fn_should_be_method.ql
 create mode 100644 cpp/ql/src/experimental/refactoring/global_variables.ql
 create mode 100644 cpp/ql/src/experimental/refactoring/printf.ql
 create mode 100644 cpp/ql/src/experimental/refactoring/relevant.qll
 create mode 100644 cpp/ql/src/experimental/refactoring/write_to_stream.ql

diff --git a/cpp/ql/src/experimental/refactoring/cstrings.ql b/cpp/ql/src/experimental/refactoring/cstrings.ql
new file mode 100644
index 00000000000..72aee25e328
--- /dev/null
+++ b/cpp/ql/src/experimental/refactoring/cstrings.ql
@@ -0,0 +1,20 @@
+import cpp
+
+class StringVariable extends Variable {
+  StringVariable() {
+    this.getType().(PointerType).stripType().getName() = "char"
+  }
+}
+
+class StringField extends StringVariable, Field
+{
+}
+
+class StringParameter extends StringVariable, Parameter
+{
+}
+
+from StringVariable f
+where f.getFile().getRelativePath().matches("c/extractor/src/%")
+and not f.getASpecifier().getName() = "extern"
+select f, f.getFile().getRelativePath()
diff --git a/cpp/ql/src/experimental/refactoring/fn_missing_namespace.ql b/cpp/ql/src/experimental/refactoring/fn_missing_namespace.ql
new file mode 100644
index 00000000000..99b428dfde9
--- /dev/null
+++ b/cpp/ql/src/experimental/refactoring/fn_missing_namespace.ql
@@ -0,0 +1,9 @@
+import cpp
+import relevant
+
+from Function fn
+where
+  fn.getNamespace() instanceof GlobalNamespace and
+  not exists(fn.getDeclaringType()) and
+  is_relevant_result(fn.getFile())
+select fn, "This function is not declared in a namespace", fn.getFile().getRelativePath()
diff --git a/cpp/ql/src/experimental/refactoring/fn_should_be_method.ql b/cpp/ql/src/experimental/refactoring/fn_should_be_method.ql
new file mode 100644
index 00000000000..6c2fef4dc44
--- /dev/null
+++ b/cpp/ql/src/experimental/refactoring/fn_should_be_method.ql
@@ -0,0 +1,4 @@
+import cpp
+
+from Function fn
+where not exists(fn.getDeclaringType()) and is_relevant_result(fn.getFile())
diff --git a/cpp/ql/src/experimental/refactoring/global_variables.ql b/cpp/ql/src/experimental/refactoring/global_variables.ql
new file mode 100644
index 00000000000..930129688a6
--- /dev/null
+++ b/cpp/ql/src/experimental/refactoring/global_variables.ql
@@ -0,0 +1,25 @@
+// Flags use of global variables
+import cpp
+
+class RelevantGlobalVariable extends GlobalVariable
+{
+  RelevantGlobalVariable() {
+    any()
+  }
+}
+
+predicate is_valid_global_variable(Variable var) {
+  var.getType().stripType().getName() = "trie_node" or
+  var.getType().isConst() or
+  var.getType().isDeeplyConst() or
+  var.isConstexpr() or
+  var.getType() instanceof ArrayType or
+  var.getASpecifier().getName() = "extern" or
+  var.getFile().getRelativePath().matches("c/extractor/edg/%")
+}
+
+from GlobalVariable globalVariable, string typeName
+where
+  not is_valid_global_variable(globalVariable) and
+  typeName = globalVariable.getType().stripType().getName()
+select globalVariable, typeName, globalVariable.getFile().getRelativePath()
diff --git a/cpp/ql/src/experimental/refactoring/printf.ql b/cpp/ql/src/experimental/refactoring/printf.ql
new file mode 100644
index 00000000000..15fe759deb1
--- /dev/null
+++ b/cpp/ql/src/experimental/refactoring/printf.ql
@@ -0,0 +1,7 @@
+import cpp
+import relevant
+
+from Call call
+where call.getTarget().getName().matches("%printf")
+and is_relevant_result(call.getFile())
+select call, "Call to a printf formatter", call.getFile().getRelativePath()
diff --git a/cpp/ql/src/experimental/refactoring/relevant.qll b/cpp/ql/src/experimental/refactoring/relevant.qll
new file mode 100644
index 00000000000..e21203a008a
--- /dev/null
+++ b/cpp/ql/src/experimental/refactoring/relevant.qll
@@ -0,0 +1,6 @@
+import cpp
+
+predicate is_relevant_result(File file)
+{
+    not file.getRelativePath().matches("c/extractor/edg%")
+}
diff --git a/cpp/ql/src/experimental/refactoring/write_to_stream.ql b/cpp/ql/src/experimental/refactoring/write_to_stream.ql
new file mode 100644
index 00000000000..45082047d2c
--- /dev/null
+++ b/cpp/ql/src/experimental/refactoring/write_to_stream.ql
@@ -0,0 +1,25 @@
+import cpp
+
+class ACompressedFileWrite extends Function {
+  ACompressedFileWrite() {
+    this.getName() = "operator<<" and
+    this.getParameter(0).getType().stripType().getName() = "a_compressed_file"
+  }
+}
+
+class LabelDefinition extends Call {
+  LabelDefinition() {
+    this.getTarget() instanceof ACompressedFileWrite and
+    this.getArgument(1).(StringLiteral).getValue().matches("=%")
+  }
+}
+
+predicate is_valid_file_write(Call call) {
+    call.getFile().getBaseName() = "dbscheme.cpp"
+}
+
+from Call call
+where
+  call.getTarget() instanceof ACompressedFileWrite
+  and not is_valid_file_write(call)
+select call