Add more methods to gdb.Progspace

There are a number of global functions in the gdb Python module which
really should be methods on Progspace.  This patch adds new methods to
Progspace and then redefines these globals in terms of these new
methods.

This version has been rebased on the related changes that Simon
recently put in.

Built and regtested on x86-64 Fedora 28.

gdb/ChangeLog
2018-09-16  Tom Tromey  <tom@tromey.com>

	* python/lib/gdb/__init__.py (current_progspace, objfiles)
	(solib_name, block_for_pc, find_pc_line): New functions.
	(execute_unwinders): Update.
	* python/py-block.c (gdbpy_block_for_pc): Remove.
	* python/py-inferior.c (infpy_get_progspace): New function.
	(inferior_object_getset) <progspace>: Add.
	* python/py-progspace.c (pspy_objfiles): Rewrite.
	(pspy_solib_name, pspy_block_for_pc)
	(pspy_find_pc_line, pspy_is_valid): New functions.
	(progspace_object_methods): Add entries for solib_name,
	block_for_pc, find_pc_line, is_valid.
	* python/python-internal.h (gdbpy_block_for_pc)
	(build_objfiles_list): Don't declare.
	* python/python.c: Don't include solib.h.
	(gdbpy_solib_name, gdbpy_find_pc_line)
	(gdbpy_get_current_progspace, build_objfiles_list)
	(gdbpy_objfiles): Remove.
	(GdbMethods) <current_progspace, objfiles, block_for_pc,
	solib_name, find_pc_line>: Remove entries.

gdb/doc/ChangeLog
2018-09-16  Tom Tromey  <tom@tromey.com>

	* python.texi (Basic Python): Update docs for find_pc_line,
	solib_name.
	(Progspaces In Python): Update docs for current_progspace.
	Document block_for_pc, find_pc_line, is_valid, nsolib_name.
	Move method documentation before example.

gdb/ChangeLog

@@ -1,3 +1,25 @@
+2018-09-16  Tom Tromey  <tom@tromey.com>
+
+	* python/lib/gdb/__init__.py (current_progspace, objfiles)
+	(solib_name, block_for_pc, find_pc_line): New functions.
+	(execute_unwinders): Update.
+	* python/py-block.c (gdbpy_block_for_pc): Remove.
+	* python/py-inferior.c (infpy_get_progspace): New function.
+	(inferior_object_getset) <progspace>: Add.
+	* python/py-progspace.c (pspy_objfiles): Rewrite.
+	(pspy_solib_name, pspy_block_for_pc)
+	(pspy_find_pc_line, pspy_is_valid): New functions.
+	(progspace_object_methods): Add entries for solib_name,
+	block_for_pc, find_pc_line, is_valid.
+	* python/python-internal.h (gdbpy_block_for_pc)
+	(build_objfiles_list): Don't declare.
+	* python/python.c: Don't include solib.h.
+	(gdbpy_solib_name, gdbpy_find_pc_line)
+	(gdbpy_get_current_progspace, build_objfiles_list)
+	(gdbpy_objfiles): Remove.
+	(GdbMethods) <current_progspace, objfiles, block_for_pc,
+	solib_name, find_pc_line>: Remove entries.
+
 2018-09-16  Tom Tromey  <tom@tromey.com>
 
 	* top.c (new_ui_command): Use GNU style for metasyntactic

gdb/doc/ChangeLog

@@ -1,3 +1,11 @@
+2018-09-16  Tom Tromey  <tom@tromey.com>
+
+	* python.texi (Basic Python): Update docs for find_pc_line,
+	solib_name.
+	(Progspaces In Python): Update docs for current_progspace.
+	Document block_for_pc, find_pc_line, is_valid, nsolib_name.
+	Move method documentation before example.
+
 2018-09-13  Simon Marchi  <simon.marchi@ericsson.com>
 
 	* python.texi (Objfiles In Python): Update gdb.objfiles() doc.

gdb/doc/python.texi

@@ -328,7 +328,9 @@ Return the @code{gdb.Symtab_and_line} object corresponding to the
 @var{pc} value.  @xref{Symbol Tables In Python}.  If an invalid
 value of @var{pc} is passed as an argument, then the @code{symtab} and
 @code{line} attributes of the returned @code{gdb.Symtab_and_line} object
-will be @code{None} and 0 respectively.
+will be @code{None} and 0 respectively.  This is identical to
+@code{gdb.current_progspace().find_pc_line(pc)} and is included for
+historical compatibility.
 @end defun
 
 @findex gdb.post_event
@@ -448,7 +450,9 @@ never returned.
 @findex gdb.solib_name
 @defun gdb.solib_name (address)
 Return the name of the shared library holding the given @var{address}
-as a string, or @code{None}.
+as a string, or @code{None}.  This is identical to
+@code{gdb.current_progspace().solib_name(address)} and is included for
+historical compatibility.
 @end defun
 
 @findex gdb.decode_line 
@@ -4035,6 +4039,45 @@ The @code{frame_filters} attribute is a dictionary of frame filter
 objects.  @xref{Frame Filter API}, for more information.
 @end defvar
 
+A program space has the following methods:
+
+@findex Progspace.block_for_pc
+@defun Progspace.block_for_pc (pc)
+Return the innermost @code{gdb.Block} containing the given @var{pc}
+value.  If the block cannot be found for the @var{pc} value specified,
+the function will return @code{None}.
+@end defun
+
+@findex Progspace.find_pc_line
+@defun Progspace.find_pc_line (pc)
+Return the @code{gdb.Symtab_and_line} object corresponding to the
+@var{pc} value.  @xref{Symbol Tables In Python}.  If an invalid value
+of @var{pc} is passed as an argument, then the @code{symtab} and
+@code{line} attributes of the returned @code{gdb.Symtab_and_line}
+object will be @code{None} and 0 respectively.
+@end defun
+
+@findex Progspace.is_valid
+@defun Progspace.is_valid ()
+Returns @code{True} if the @code{gdb.Progspace} object is valid,
+@code{False} if not.  A @code{gdb.Progspace} object can become invalid
+if the program space file it refers to is not referenced by any
+inferior.  All other @code{gdb.Progspace} methods will throw an
+exception if it is invalid at the time the method is called.
+@end defun
+
+@findex Progspace.objfiles
+@defun Progspace.objfiles ()
+Return a sequence of all the objfiles referenced by this program
+space.  @xref{Objfiles In Python}.
+@end defun
+
+@findex Progspace.solib_name
+@defun Progspace.solib_name (address)
+Return the name of the shared library holding the given @var{address}
+as a string, or @code{None}.
+@end defun
+
 One may add arbitrary attributes to @code{gdb.Progspace} objects
 in the usual Python way.
 This is useful if, for example, one needs to do some extra record keeping
@@ -4079,14 +4122,6 @@ Hello.
 [Inferior 1 (process 4242) exited normally]
 @end smallexample
 
-A @code{gdb.Progspace} object has the following methods:
-
-@findex Progspace.objfiles
-@defun Progspace.objfiles ()
-Return a sequence of all the objfiles referenced by this program
-space.  @xref{Objfiles In Python}.
-@end defun
-
 @node Objfiles In Python
 @subsubsection Objfiles In Python
 
@@ -4515,7 +4550,9 @@ module:
 @defun gdb.block_for_pc (pc)
 Return the innermost @code{gdb.Block} containing the given @var{pc}
 value.  If the block cannot be found for the @var{pc} value specified,
-the function will return @code{None}.
+the function will return @code{None}.  This is identical to
+@code{gdb.current_progspace().block_for_pc(pc)} and is included for
+historical compatibility.
 @end defun
 
 A @code{gdb.Block} object has the following methods:

gdb/python/lib/gdb/__init__.py

@@ -85,15 +85,14 @@ def execute_unwinders(pending_frame):
     Returns:
         gdb.UnwindInfo instance or None.
     """
-    for objfile in _gdb.objfiles():
+    for objfile in objfiles():
         for unwinder in objfile.frame_unwinders:
             if unwinder.enabled:
                 unwind_info = unwinder(pending_frame)
                 if unwind_info is not None:
                     return unwind_info
 
-    current_progspace = _gdb.current_progspace()
+    for unwinder in current_progspace().frame_unwinders:
-    for unwinder in current_progspace.frame_unwinders:
         if unwinder.enabled:
             unwind_info = unwinder(pending_frame)
             if unwind_info is not None:
@@ -163,3 +162,25 @@ def GdbSetPythonDirectory(dir):
     # attributes
     reload(__import__(__name__))
     auto_load_packages()
+
+def current_progspace():
+    "Return the current Progspace."
+    return selected_inferior().progspace
+
+def objfiles():
+    "Return a sequence of the current program space's objfiles."
+    return current_progspace().objfiles()
+
+def solib_name (addr):
+    """solib_name (Long) -> String.\n\
+Return the name of the shared library holding a given address, or None."""
+    return current_progspace().solib_name(addr)
+
+def block_for_pc(pc):
+    "Return the block containing the given pc value, or None."
+    return current_progspace().block_for_pc(pc)
+
+def find_pc_line(pc):
+    """find_pc_line (pc) -> Symtab_and_line.
+Return the gdb.Symtab_and_line object corresponding to the pc value."""
+    return current_progspace().find_pc_line(pc)

gdb/python/py-block.c

@@ -366,44 +366,6 @@ blpy_iter_is_valid (PyObject *self, PyObject *args)
   Py_RETURN_TRUE;
 }
 
-/* Return the innermost lexical block containing the specified pc value,
-   or 0 if there is none.  */
-PyObject *
-gdbpy_block_for_pc (PyObject *self, PyObject *args)
-{
-  gdb_py_ulongest pc;
-  const struct block *block = NULL;
-  struct compunit_symtab *cust = NULL;
-
-  if (!PyArg_ParseTuple (args, GDB_PY_LLU_ARG, &pc))
-    return NULL;
-
-  TRY
-    {
-      cust = find_pc_compunit_symtab (pc);
-
-      if (cust != NULL && COMPUNIT_OBJFILE (cust) != NULL)
-	block = block_for_pc (pc);
-    }
-  CATCH (except, RETURN_MASK_ALL)
-    {
-      GDB_PY_HANDLE_EXCEPTION (except);
-    }
-  END_CATCH
-
-  if (cust == NULL || COMPUNIT_OBJFILE (cust) == NULL)
-    {
-      PyErr_SetString (PyExc_RuntimeError,
-		       _("Cannot locate object file for block."));
-      return NULL;
-    }
-
-  if (block)
-    return block_to_block_object (block, COMPUNIT_OBJFILE (cust));
-
-  Py_RETURN_NONE;
-}
-
 /* This function is called when an objfile is about to be freed.
    Invalidate the block as further actions on the block would result
    in bad data.  All access to obj->symbol should be gated by

gdb/python/py-progspace.c

@@ -25,6 +25,8 @@
 #include "language.h"
 #include "arch-utils.h"
 #include "py-ref.h"
+#include "solib.h"
+#include "block.h"
 
 typedef struct
 {
@@ -332,9 +334,143 @@ pspy_get_objfiles (PyObject *self_, PyObject *args)
 
   PSPY_REQUIRE_VALID (self);
 
-  return build_objfiles_list (self->pspace).release ();
+  gdbpy_ref<> list (PyList_New (0));
+  if (list == NULL)
+    return NULL;
+
+  if (self->pspace != NULL)
+    {
+      struct objfile *objf;
+
+      ALL_PSPACE_OBJFILES (self->pspace, objf)
+	{
+	  PyObject *item = objfile_to_objfile_object (objf);
+
+	  if (!item || PyList_Append (list.get (), item) == -1)
+	    return NULL;
+	}
+    }
+
+  return list.release ();
 }
 
+/* Implementation of solib_name (Long) -> String.
+   Returns the name of the shared library holding a given address, or None.  */
+
+static PyObject *
+pspy_solib_name (PyObject *o, PyObject *args)
+{
+  char *soname;
+  gdb_py_longest pc;
+  pspace_object *self = (pspace_object *) o;
+
+  PSPY_REQUIRE_VALID (self);
+
+  if (!PyArg_ParseTuple (args, GDB_PY_LLU_ARG, &pc))
+    return NULL;
+
+  soname = solib_name_from_address (self->pspace, pc);
+  if (soname == nullptr)
+    Py_RETURN_NONE;
+  return host_string_to_python_string (soname);
+}
+
+/* Return the innermost lexical block containing the specified pc value,
+   or 0 if there is none.  */
+static PyObject *
+pspy_block_for_pc (PyObject *o, PyObject *args)
+{
+  pspace_object *self = (pspace_object *) o;
+  gdb_py_ulongest pc;
+  const struct block *block = NULL;
+  struct compunit_symtab *cust = NULL;
+
+  PSPY_REQUIRE_VALID (self);
+
+  if (!PyArg_ParseTuple (args, GDB_PY_LLU_ARG, &pc))
+    return NULL;
+
+  TRY
+    {
+      scoped_restore_current_program_space saver;
+
+      set_current_program_space (self->pspace);
+      cust = find_pc_compunit_symtab (pc);
+
+      if (cust != NULL && COMPUNIT_OBJFILE (cust) != NULL)
+	block = block_for_pc (pc);
+    }
+  CATCH (except, RETURN_MASK_ALL)
+    {
+      GDB_PY_HANDLE_EXCEPTION (except);
+    }
+  END_CATCH
+
+  if (cust == NULL || COMPUNIT_OBJFILE (cust) == NULL)
+    {
+      PyErr_SetString (PyExc_RuntimeError,
+		       _("Cannot locate object file for block."));
+      return NULL;
+    }
+
+  if (block)
+    return block_to_block_object (block, COMPUNIT_OBJFILE (cust));
+
+  Py_RETURN_NONE;
+}
+
+/* Implementation of the find_pc_line function.
+   Returns the gdb.Symtab_and_line object corresponding to a PC value.  */
+
+static PyObject *
+pspy_find_pc_line (PyObject *o, PyObject *args)
+{
+  gdb_py_ulongest pc_llu;
+  PyObject *result = NULL; /* init for gcc -Wall */
+  pspace_object *self = (pspace_object *) o;
+
+  PSPY_REQUIRE_VALID (self);
+
+  if (!PyArg_ParseTuple (args, GDB_PY_LLU_ARG, &pc_llu))
+    return NULL;
+
+  TRY
+    {
+      struct symtab_and_line sal;
+      CORE_ADDR pc;
+      scoped_restore_current_program_space saver;
+
+      set_current_program_space (self->pspace);
+
+      pc = (CORE_ADDR) pc_llu;
+      sal = find_pc_line (pc, 0);
+      result = symtab_and_line_to_sal_object (sal);
+    }
+  CATCH (except, RETURN_MASK_ALL)
+    {
+      GDB_PY_HANDLE_EXCEPTION (except);
+    }
+  END_CATCH
+
+  return result;
+}
+
+/* Implementation of is_valid (self) -> Boolean.
+   Returns True if this program space still exists in GDB.  */
+
+static PyObject *
+pspy_is_valid (PyObject *o, PyObject *args)
+{
+  pspace_object *self = (pspace_object *) o;
+
+  if (self->pspace == NULL)
+    Py_RETURN_FALSE;
+
+  Py_RETURN_TRUE;
+}
+
+
+
 /* Clear the PSPACE pointer in a Pspace object and remove the reference.  */
 
 static void
@@ -420,6 +556,17 @@ static PyMethodDef progspace_object_methods[] =
 {
   { "objfiles", pspy_get_objfiles, METH_NOARGS,
     "Return a sequence of objfiles associated to this program space." },
+  { "solib_name", pspy_solib_name, METH_VARARGS,
+    "solib_name (Long) -> String.\n\
+Return the name of the shared library holding a given address, or None." },
+  { "block_for_pc", pspy_block_for_pc, METH_VARARGS,
+    "Return the block containing the given pc value, or None." },
+  { "find_pc_line", pspy_find_pc_line, METH_VARARGS,
+    "find_pc_line (pc) -> Symtab_and_line.\n\
+Return the gdb.Symtab_and_line object corresponding to the pc value." },
+  { "is_valid", pspy_is_valid, METH_NOARGS,
+    "is_valid () -> Boolean.\n\
+Return true if this program space is valid, false if not." },
   { NULL }
 };
 

gdb/python/python-internal.h

@@ -492,7 +492,6 @@ PyObject *gdbpy_current_recording (PyObject *self, PyObject *args);
 PyObject *gdbpy_stop_recording (PyObject *self, PyObject *args);
 PyObject *gdbpy_newest_frame (PyObject *self, PyObject *args);
 PyObject *gdbpy_selected_frame (PyObject *self, PyObject *args);
-PyObject *gdbpy_block_for_pc (PyObject *self, PyObject *args);
 PyObject *gdbpy_lookup_type (PyObject *self, PyObject *args, PyObject *kw);
 int gdbpy_is_field (PyObject *obj);
 PyObject *gdbpy_create_lazy_string_object (CORE_ADDR address, long length,
@@ -549,10 +548,6 @@ struct symtab_and_line *sal_object_to_symtab_and_line (PyObject *obj);
 struct frame_info *frame_object_to_frame_info (PyObject *frame_obj);
 struct gdbarch *arch_object_to_gdbarch (PyObject *obj);
 
-/* Return a Python list containing an Objfile object for each objfile in
-   PSPACE.  */
-gdbpy_ref<> build_objfiles_list (program_space *pspace);
-
 void gdbpy_initialize_gdb_readline (void);
 int gdbpy_initialize_auto_load (void)
   CPYCHECKER_NEGATIVE_RESULT_SETS_EXCEPTION;

gdb/python/python.c

@@ -90,7 +90,6 @@ const struct extension_language_defn extension_language_python =
 #include "cli/cli-decode.h"
 #include "charset.h"
 #include "top.h"
-#include "solib.h"
 #include "python-internal.h"
 #include "linespec.h"
 #include "source.h"
@@ -635,31 +634,6 @@ execute_gdb_command (PyObject *self, PyObject *args, PyObject *kw)
   Py_RETURN_NONE;
 }
 
-/* Implementation of gdb.solib_name (Long) -> String.
-   Returns the name of the shared library holding a given address, or None.  */
-
-static PyObject *
-gdbpy_solib_name (PyObject *self, PyObject *args)
-{
-  char *soname;
-  PyObject *str_obj;
-  gdb_py_ulongest pc;
-
-  if (!PyArg_ParseTuple (args, GDB_PY_LLU_ARG, &pc))
-    return NULL;
-
-  soname = solib_name_from_address (current_program_space, pc);
-  if (soname)
-    str_obj = host_string_to_python_string (soname);
-  else
-    {
-      str_obj = Py_None;
-      Py_INCREF (Py_None);
-    }
-
-  return str_obj;
-}
-
 /* Implementation of Python rbreak command.  Take a REGEX and
    optionally a MINSYMS, THROTTLE and SYMTABS keyword and return a
    Python list that contains newly set breakpoints that match that
@@ -945,36 +919,6 @@ gdbpy_parse_and_eval (PyObject *self, PyObject *args)
   return value_to_value_object (result);
 }
 
-/* Implementation of gdb.find_pc_line function.
-   Returns the gdb.Symtab_and_line object corresponding to a PC value.  */
-
-static PyObject *
-gdbpy_find_pc_line (PyObject *self, PyObject *args)
-{
-  gdb_py_ulongest pc_llu;
-  PyObject *result = NULL; /* init for gcc -Wall */
-
-  if (!PyArg_ParseTuple (args, GDB_PY_LLU_ARG, &pc_llu))
-    return NULL;
-
-  TRY
-    {
-      struct symtab_and_line sal;
-      CORE_ADDR pc;
-
-      pc = (CORE_ADDR) pc_llu;
-      sal = find_pc_line (pc, 0);
-      result = symtab_and_line_to_sal_object (sal);
-    }
-  CATCH (except, RETURN_MASK_ALL)
-    {
-      GDB_PY_HANDLE_EXCEPTION (except);
-    }
-  END_CATCH
-
-  return result;
-}
-
 /* Implementation of gdb.invalidate_cached_frames.  */
 
 static PyObject *
@@ -1336,20 +1280,6 @@ gdbpy_print_stack (void)
 
 
 
-/* Return the current Progspace.
-   There always is one.  */
-
-static PyObject *
-gdbpy_get_current_progspace (PyObject *unused1, PyObject *unused2)
-{
-  PyObject *result;
-
-  result = pspace_to_pspace_object (current_program_space);
-  if (result)
-    Py_INCREF (result);
-  return result;
-}
-
 /* Return a sequence holding all the Progspaces.  */
 
 static PyObject *
@@ -1440,36 +1370,6 @@ gdbpy_get_current_objfile (PyObject *unused1, PyObject *unused2)
   return result;
 }
 
-/* See python-internal.h.  */
-
-gdbpy_ref<>
-build_objfiles_list (program_space *pspace)
-{
-  struct objfile *objf;
-
-  gdbpy_ref<> list (PyList_New (0));
-  if (list == NULL)
-    return NULL;
-
-  ALL_PSPACE_OBJFILES (pspace, objf)
-    {
-      PyObject *item = objfile_to_objfile_object (objf);
-
-      if (item == nullptr || PyList_Append (list.get (), item) == -1)
-	return NULL;
-    }
-
-  return list;
-}
-
-/* Return a sequence holding all the Objfiles.  */
-
-static PyObject *
-gdbpy_objfiles (PyObject *unused1, PyObject *unused2)
-{
-  return build_objfiles_list (current_program_space).release ();
-}
-
 /* Compute the list of active python type printers and store them in
    EXT_PRINTERS->py_type_printers.  The product of this function is used by
    gdbpy_apply_type_printers, and freed by gdbpy_free_type_printers.
@@ -2045,15 +1945,11 @@ set to True." },
   { "default_visualizer", gdbpy_default_visualizer, METH_VARARGS,
     "Find the default visualizer for a Value." },
 
-  { "current_progspace", gdbpy_get_current_progspace, METH_NOARGS,
-    "Return the current Progspace." },
   { "progspaces", gdbpy_progspaces, METH_NOARGS,
     "Return a sequence of all progspaces." },
 
   { "current_objfile", gdbpy_get_current_objfile, METH_NOARGS,
     "Return the current Objfile being loaded, or None." },
-  { "objfiles", gdbpy_objfiles, METH_NOARGS,
-    "Return a sequence of all loaded objfiles." },
 
   { "newest_frame", gdbpy_newest_frame, METH_NOARGS,
     "newest_frame () -> gdb.Frame.\n\
@@ -2099,11 +1995,6 @@ Look up the specified objfile.\n\
 If by_build_id is True, the objfile is looked up by using name\n\
 as its build id." },
 
-  { "block_for_pc", gdbpy_block_for_pc, METH_VARARGS,
-    "Return the block containing the given pc value, or None." },
-  { "solib_name", gdbpy_solib_name, METH_VARARGS,
-    "solib_name (Long) -> String.\n\
-Return the name of the shared library holding a given address, or None." },
   { "decode_line", gdbpy_decode_line, METH_VARARGS,
     "decode_line (String) -> Tuple.  Decode a string argument the way\n\
 that 'break' or 'edit' does.  Return a tuple containing two elements.\n\
@@ -2115,9 +2006,6 @@ gdb.Symtab_and_line objects (or None)."},
     "parse_and_eval (String) -> Value.\n\
 Parse String as an expression, evaluate it, and return the result as a Value."
   },
-  { "find_pc_line", gdbpy_find_pc_line, METH_VARARGS,
-    "find_pc_line (pc) -> Symtab_and_line.\n\
-Return the gdb.Symtab_and_line object corresponding to the pc value." },
 
   { "post_event", gdbpy_post_event, METH_VARARGS,
     "Post an event into gdb's event loop." },