# If you use the GNU debugger gdb to debug the Python C runtime, you

# might find some of the following commands useful. Copy this to your

# ~/.gdbinit file and it'll get loaded into gdb automatically when you

# start it up. Then, at the gdb prompt you can do things like:

#

# (gdb) pyo apyobjectptr

# <module 'foobar' (built-in)>

# refcounts: 1

# address : 84a7a2c

# $1 = void

# (gdb)

#

# NOTE: If you have gdb 7 or later, it supports debugging of Python directly

# with embedded macros that you may find superior to what is in here.

# See Tools/gdb/libpython.py and http://bugs.python.org/issue8032.

# Prints a representation of the object to stderr, along with the

# number of reference counts it current has and the hex address the

# object is allocated at. The argument must be a PyObject*

define pyo

# side effect of calling _PyObject_Dump is to dump the object's

# info - assigning just prevents gdb from printing the

# NULL return value

set $_unused_void = _PyObject_Dump($arg0)

end

# Prints a representation of the object to stderr, along with the

# number of reference counts it current has and the hex address the

# object is allocated at. The argument must be a PyGC_Head*

define pyg

print _PyGC_Dump($arg0)

end

# print the local variables of the current frame

define pylocals

set $_i = 0

while $_i < f->f_code->co_nlocals

if f->f_localsplus + $_i != 0

set $_names = co->co_varnames

set $_name = _PyUnicode_AsString(PyTuple_GetItem($_names, $_i))

printf "%s:\n", $_name

pyo f->f_localsplus[$_i]

end

set $_i = $_i + 1

end

end

# A rewrite of the Python interpreter's line number calculator in GDB's

# command language

define lineno

set $__continue = 1

set $__co = f->f_code

set $__lasti = f->f_lasti

set $__sz = ((PyVarObject *)$__co->co_lnotab)->ob_size/2

set $__p = (unsigned char *)((PyBytesObject *)$__co->co_lnotab)->ob_sval

set $__li = $__co->co_firstlineno

set $__ad = 0

while ($__sz-1 >= 0 && $__continue)

set $__sz = $__sz - 1

set $__ad = $__ad + *$__p

set $__p = $__p + 1

if ($__ad > $__lasti)

set $__continue = 0

else

set $__li = $__li + *$__p

set $__p = $__p + 1

end

end

printf "%d", $__li

end

# print the current frame - verbose

define pyframev

pyframe

pylocals

end

define pyframe

set $__fn = _PyUnicode_AsString(co->co_filename)

set $__n = _PyUnicode_AsString(co->co_name)

printf "%s (", $__fn

lineno

printf "): %s\n", $__n

### Uncomment these lines when using from within Emacs/XEmacs so it will

### automatically track/display the current Python source line

# printf "%c%c%s:", 032, 032, $__fn

# lineno

# printf ":1\n"

end

### Use these at your own risk. It appears that a bug in gdb causes it

### to crash in certain circumstances.

#define up

# up-silently 1

# printframe

#end

#define down

# down-silently 1

# printframe

#end

define printframe

if $pc > PyEval_EvalFrameEx && $pc < PyEval_EvalCodeEx

pyframe

else

frame

end

end

# Here's a somewhat fragile way to print the entire Python stack from gdb.

# It's fragile because the tests for the value of $pc depend on the layout

# of specific functions in the C source code.

# Explanation of while and if tests: We want to pop up the stack until we

# land in Py_Main (this is probably an incorrect assumption in an embedded

# interpreter, but the test can be extended by an interested party). If

# Py_Main <= $pc <= Py_GetArgcArv is true, $pc is in Py_Main(), so the while

# tests succeeds as long as it's not true. In a similar fashion the if

# statement tests to see if we are in PyEval_EvalFrameEx().

# Note: The name of the main interpreter function and the function which

# follow it has changed over time. This version of pystack works with this

# version of Python. If you try using it with older or newer versions of

# the interpreter you may will have to change the functions you compare with

# $pc.

# print the entire Python call stack

define pystack

while $pc < Py_Main || $pc > Py_GetArgcArgv

if $pc > PyEval_EvalFrameEx && $pc < PyEval_EvalCodeEx

pyframe

end

up-silently 1

end

select-frame 0

end

# print the entire Python call stack - verbose mode

define pystackv

while $pc < Py_Main || $pc > Py_GetArgcArgv

if $pc > PyEval_EvalFrameEx && $pc < PyEval_EvalCodeEx

pyframev

end

up-silently 1

end

select-frame 0

end

# generally useful macro to print a Unicode string

def pu

set $uni = $arg0

set $i = 0

while (*$uni && $i++<100)

if (*$uni < 0x80)

print *(char*)$uni++

else

print /x *(short*)$uni++

end

end

end