diff --git a/gdb/NEWS b/gdb/NEWS index 1397e8b..3db458b 100644 --- a/gdb/NEWS +++ b/gdb/NEWS @@ -3,6 +3,9 @@ *** Changes since GDB 7.7 +* Python Scripting + You can now access frame registers from Python scripts. + * New command line options -D data-directory diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi index 4688783..3cb6bf8 100644 --- a/gdb/doc/python.texi +++ b/gdb/doc/python.texi @@ -3589,6 +3589,13 @@ Return the frame's symtab and line object. @xref{Symbol Tables In Python}. @end defun +@defun Frame.read_register (register) +Return the value of @var{register} in this frame. The @var{register} +argument must be a string (e.g., @code{'sp'} or @code{'rax'}). +Returns a @code{Gdb.Value} object. Throws an exception if @var{register} +does not exist. +@end defun + @defun Frame.read_var (variable @r{[}, block@r{]}) Return the value of @var{variable} in this frame. If the optional argument @var{block} is provided, search for the variable from that diff --git a/gdb/python/py-frame.c b/gdb/python/py-frame.c index 77077d3..73bffb1 100644 --- a/gdb/python/py-frame.c +++ b/gdb/python/py-frame.c @@ -28,6 +28,7 @@ #include "python-internal.h" #include "symfile.h" #include "objfiles.h" +#include "user-regs.h" typedef struct { PyObject_HEAD @@ -235,6 +236,39 @@ frapy_pc (PyObject *self, PyObject *args) return gdb_py_long_from_ulongest (pc); } +/* Implementation of gdb.Frame.read_register (self, register) -> gdb.Value. + Returns the value of a register in this frame. */ + +static PyObject * +frapy_read_register (PyObject *self, PyObject *args) +{ + struct frame_info *frame; + volatile struct gdb_exception except; + int regnum = -1; + struct value *val = NULL; + const char *regnum_str; + + if (!PyArg_ParseTuple (args, "s", ®num_str)) + return NULL; + + TRY_CATCH (except, RETURN_MASK_ALL) + { + FRAPY_REQUIRE_VALID (self, frame); + + regnum = user_reg_map_name_to_regnum (get_frame_arch (frame), + regnum_str, + strlen (regnum_str)); + if (regnum >= 0) + val = value_of_register (regnum, frame); + + if (val == NULL) + PyErr_SetString (PyExc_ValueError, _("Unknown register.")); + } + GDB_PY_HANDLE_EXCEPTION (except); + + return val == NULL ? NULL : value_to_value_object (val); +} + /* Implementation of gdb.Frame.block (self) -> gdb.Block. Returns the frame's code block. */ @@ -674,6 +708,9 @@ Return the reason why it's not possible to find frames older than this." }, { "pc", frapy_pc, METH_NOARGS, "pc () -> Long.\n\ Return the frame's resume address." }, + { "read_register", frapy_read_register, METH_VARARGS, + "read_register (register) -> gdb.Value\n\ +Return the value of the register in the frame." }, { "block", frapy_block, METH_NOARGS, "block () -> gdb.Block.\n\ Return the frame's code block." }, diff --git a/gdb/testsuite/gdb.python/py-frame.exp b/gdb/testsuite/gdb.python/py-frame.exp index 3517824..9eeebba 100644 --- a/gdb/testsuite/gdb.python/py-frame.exp +++ b/gdb/testsuite/gdb.python/py-frame.exp @@ -94,3 +94,16 @@ gdb_test "python print ('result = %s' % f0.read_var ('variable_which_surely_does gdb_test "python print ('result = %s' % f0.read_var ('a'))" " = 1" "test Frame.read_var - success" gdb_test "python print ('result = %s' % (gdb.selected_frame () == f1))" " = True" "test gdb.selected_frame" + +# Can read SP register. +gdb_test "python print ('result = %s' % f0.read_register('sp'))" \ + " = 0x\[0-9a-fA-F\]+" \ + "test Frame.read_register(fp)" +# PC value obtained via read_register is as expected. +gdb_test "python print ('result = %s' % (f0.read_register('pc').cast(gdb.lookup_type('unsigned long')) == f0.pc()))" \ + "True" \ + "test Frame.read_register(pc)" +# On x86-64, PC is in $rip register. +gdb_test "python print ('result = %s' % ((f0.architecture().name() != 'i386:x86-64') or f0.read_register('pc') == f0.read_register('rip')))" \ + "True" \ + "test Frame.read_register(regnum)"