/* This code was taken from https://github.com/GoogleCloudPlatform/cloud-profiler-python/blob/main/googlecloudprofiler/src/populate_frames.cc */

#include "populate_frames.h"

#include <Python.h>

// 0x030B0000 is 3.11.

#define PY_311 0x030B0000

#if PY_VERSION_HEX >= PY_311

/**

* The PyFrameObject structure members have been removed from the public C API

* in 3.11:

https://docs.python.org/3/whatsnew/3.11.html#pyframeobject-3-11-hiding.

*

* Instead, getters are provided which participate in reference counting; since

* this code runs as part of the SIGPROF handler, it cannot modify Python

* objects (including their refcounts) and the getters can't be used. Instead,

* we expose the internal _PyInterpreterFrame and use that directly.

*

*/

#define Py_BUILD_CORE

#include "internal/pycore_frame.h"

#undef Py_BUILD_CORE

// Modified from

// https://github.com/python/cpython/blob/v3.11.4/Python/pystate.c#L1278-L1285

_PyInterpreterFrame *unsafe_PyThreadState_GetInterpreterFrame(

PyThreadState *tstate) {

assert(tstate != NULL);

_PyInterpreterFrame *f = tstate->cframe->current_frame;

while (f && _PyFrame_IsIncomplete(f)) {

f = f->previous;

}

if (f == NULL) {

return NULL;

}

return f;

}

// Modified from

// https://github.com/python/cpython/blob/v3.11.4/Objects/frameobject.c#L1310-L1315

// with refcounting removed

PyCodeObject *unsafe_PyInterpreterFrame_GetCode(

_PyInterpreterFrame *frame) {

assert(frame != NULL);

assert(!_PyFrame_IsIncomplete(frame));

PyCodeObject *code = frame->f_code;

assert(code != NULL);

return code;

}

// Modified from

// https://github.com/python/cpython/blob/v3.11.4/Objects/frameobject.c#L1326-L1329

// with refcounting removed

_PyInterpreterFrame *unsafe_PyInterpreterFrame_GetBack(

_PyInterpreterFrame *frame) {

assert(frame != NULL);

assert(!_PyFrame_IsIncomplete(frame));

_PyInterpreterFrame *prev = frame->previous;

while (prev && _PyFrame_IsIncomplete(prev)) {

prev = prev->previous;

}

return prev;

}

// Copied from

// https://github.com/python/cpython/blob/v3.11.4/Python/frame.c#L165-L170 as

// this function is not available in libpython

int _PyInterpreterFrame_GetLine(_PyInterpreterFrame *frame) {

int addr = _PyInterpreterFrame_LASTI(frame) * sizeof(_Py_CODEUNIT);

return PyCode_Addr2Line(frame->f_code, addr);

}

#endif // PY_VERSION_HEX >= PY_311