[v3] Add more methods to gdb.Progspace

diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi
index aca6ec858cf..34f42c0effe 100644
--- a/gdb/doc/python.texi
+++ b/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{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{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{current_progspace().block_for_pc(pc)} and is included for
+historical compatibility.
 @end defun
 
 A @code{gdb.Block} object has the following methods:
diff --git a/gdb/python/lib/gdb/__init__.py b/gdb/python/lib/gdb/__init__.py
index 7e7c299f3c7..c223f2bac3d 100644
--- a/gdb/python/lib/gdb/__init__.py
+++ b/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)
diff --git a/gdb/python/py-block.c b/gdb/python/py-block.c
index 70a0a76dc43..5fc33f0f0fb 100644
--- a/gdb/python/py-block.c
+++ b/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
diff --git a/gdb/python/py-progspace.c b/gdb/python/py-progspace.c
index e01338f43d3..17970a892b7 100644
--- a/gdb/python/py-progspace.c
+++ b/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 +334,150 @@  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;
+  PyObject *str_obj;
+  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)
+    str_obj = host_string_to_python_string (soname);
+  else
+    {
+      str_obj = Py_None;
+      Py_INCREF (Py_None);
+    }
+
+  return str_obj;
+}
+
+/* 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 +563,17 @@  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 }
 };
 
diff --git a/gdb/python/python-internal.h b/gdb/python/python-internal.h
index 785ad171511..1c526af1586 100644
--- a/gdb/python/python-internal.h
+++ b/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;
diff --git a/gdb/python/python.c b/gdb/python/python.c
index 371f4a57529..1859331df01 100644
--- a/gdb/python/python.c
+++ b/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"
@@ -632,31 +631,6 @@  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
@@ -942,36 +916,6 @@  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 *
@@ -1333,20 +1277,6 @@  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 *
@@ -1437,36 +1367,6 @@  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.
@@ -2042,15 +1942,11 @@  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\
@@ -2096,11 +1992,6 @@  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\
@@ -2112,9 +2003,6 @@  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." },