A technicality: if should_trace returned a non-string, it would leak.

1 files changed, 11 insertions, 3 deletions

diff --git a/coverage/tracer.c b/coverage/tracer.c
index 9c079cbb..e5d1e06a 100644
--- a/coverage/tracer.c
+++ b/coverage/tracer.c
@@ -16,6 +16,8 @@
 

 // The Tracer type.

 

+#define MAX_STACK_DEPTH 500

+

 typedef struct {

     PyObject_HEAD

     PyObject * should_trace;

@@ -25,7 +27,7 @@ typedef struct {
     // The index of the last-used entry in tracenames.

     int depth;

     // Filenames to record at each level, or NULL if not recording.

-    PyObject * tracenames[300];

+    PyObject * tracenames[MAX_STACK_DEPTH];

 } Tracer;

 

 static int

@@ -69,7 +71,7 @@ Tracer_trace(Tracer *self, PyFrameObject *frame, int what, PyObject *arg)
     switch (what) {

     case PyTrace_CALL:      // 0

         self->depth++;

-        if (self->depth > sizeof(self->tracenames)/sizeof(self->tracenames[0])) {

+        if (self->depth > MAX_STACK_DEPTH) {

             PyErr_SetString(PyExc_RuntimeError, "Tracer stack overflow");

             return -1;

         }

@@ -92,7 +94,13 @@ Tracer_trace(Tracer *self, PyFrameObject *frame, int what, PyObject *arg)
         }

 

         // If tracename is a string, then we're supposed to trace.

-        self->tracenames[self->depth] = PyString_Check(tracename) ? tracename : NULL;

+        if (PyString_Check(tracename)) {

+            self->tracenames[self->depth] = tracename;

+        }

+        else {

+            self->tracenames[self->depth] = NULL;

+            Py_DECREF(tracename);

+        }

         break;

     

     case PyTrace_RETURN:    // 3