[PATCH v5 07/15] gdb, python: use gdbarch_iterate_over_objfiles_in_search_order

Markus Metzger via Gdb-patches
2022-06-02T14:32:15Z

The implementation of gdb.lookup_objfile() iterates over all objfiles and
compares their name or build id to the user-provided search string.

This will cause problems when supporting linker namespaces as the first
objfile in any namespace will be found. Instead, use
gdbarch_iterate_over_objfiles_in_search_order to only consider the
namespace of gdb.current_objfile() for the search, which defaults to the
initial namespace when gdb.current_objfile() is None.
---
gdb/python/py-objfile.c | 116 +++++++++++++++++++---------------------
gdb/python/python.c | 7 +--
gdb/python/python.h | 6 +++
3 files changed, 64 insertions(+), 65 deletions(-)

diff --git a/gdb/python/py-objfile.c b/gdb/python/py-objfile.c
index 3e3270e7cd3..b278cec99d8 100644
--- a/gdb/python/py-objfile.c
+++ b/gdb/python/py-objfile.c
@@ -24,6 +24,7 @@
#include "language.h"
#include "build-id.h"
#include "symtab.h"
+#include "python.h"

struct objfile_object
{
@@ -559,57 +560,6 @@ objfpy_build_id_matches (const struct bfd_build_id *build_id,
return 1;
}

-/* Subroutine of gdbpy_lookup_objfile to simplify it.
- Look up an objfile by its file name. */
-
-static struct objfile *
-objfpy_lookup_objfile_by_name (const char *name)
-{
- for (objfile *objfile : current_program_space->objfiles ())
- {
- const char *filename;
-
- if ((objfile->flags & OBJF_NOT_FILENAME) != 0)
- continue;
- /* Don't return separate debug files. */
- if (objfile->separate_debug_objfile_backlink != NULL)
- continue;
-
- filename = objfile_filename (objfile);
- if (filename != NULL && compare_filenames_for_search (filename, name))
- return objfile;
- if (compare_filenames_for_search (objfile->original_name, name))
- return objfile;
- }
-
- return NULL;
-}
-
-/* Subroutine of gdbpy_lookup_objfile to simplify it.
- Look up an objfile by its build id. */
-
-static struct objfile *
-objfpy_lookup_objfile_by_build_id (const char *build_id)
-{
- for (objfile *objfile : current_program_space->objfiles ())
- {
- const struct bfd_build_id *obfd_build_id;
-
- if (objfile->obfd == NULL)
- continue;
- /* Don't return separate debug files. */
- if (objfile->separate_debug_objfile_backlink != NULL)
- continue;
- obfd_build_id = build_id_bfd_get (objfile->obfd);
- if (obfd_build_id == NULL)
- continue;
- if (objfpy_build_id_matches (obfd_build_id, build_id))
- return objfile;
- }
-
- return NULL;
-}
-
/* Implementation of gdb.lookup_objfile. */

PyObject *
@@ -619,7 +569,6 @@ gdbpy_lookup_objfile (PyObject *self, PyObject *args, PyObject *kw)
const char *name;
PyObject *by_build_id_obj = NULL;
int by_build_id;
- struct objfile *objfile;

if (!gdb_PyArg_ParseTupleAndKeywords (args, kw, "s|O!", keywords,
&name, &PyBool_Type, &by_build_id_obj))
@@ -635,17 +584,64 @@ gdbpy_lookup_objfile (PyObject *self, PyObject *args, PyObject *kw)
by_build_id = cmp;
}

- if (by_build_id)
+ if (by_build_id && !objfpy_build_id_ok (name))
{
- if (!objfpy_build_id_ok (name))
- {
- PyErr_SetString (PyExc_TypeError, _("Not a valid build id."));
- return NULL;
- }
- objfile = objfpy_lookup_objfile_by_build_id (name);
+ PyErr_SetString (PyExc_TypeError, _("Not a valid build id."));
+ return NULL;
}
+
+ struct objfile *objfile = nullptr;
+ if (by_build_id)
+ gdbarch_iterate_over_objfiles_in_search_order
+ (target_gdbarch (),
+ [&objfile, name] (struct objfile *obj)
+ {
+ /* Don't return separate debug files. */
+ if (obj->separate_debug_objfile_backlink != nullptr)
+ return 0;
+
+ bfd *obfd = obj->obfd;
+ if (obfd == nullptr)
+ return 0;
+
+ const bfd_build_id *obfd_build_id = build_id_bfd_get (obfd);
+ if (obfd_build_id == nullptr)
+ return 0;
+
+ if (!objfpy_build_id_matches (obfd_build_id, name))
+ return 0;
+
+ objfile = obj;
+ return 1;
+ }, gdbpy_current_objfile);
else
- objfile = objfpy_lookup_objfile_by_name (name);
+ gdbarch_iterate_over_objfiles_in_search_order
+ (target_gdbarch (),
+ [&objfile, name] (struct objfile *obj)
+ {
+ /* Don't return separate debug files. */
+ if (obj->separate_debug_objfile_backlink != nullptr)
+ return 0;
+
+ if ((obj->flags & OBJF_NOT_FILENAME) != 0)
+ return 0;
+
+ const char *filename = objfile_filename (obj);
+ if (filename != NULL
+ && compare_filenames_for_search (filename, name))
+ {
+ objfile = obj;
+ return 1;
+ }
+
+ if (compare_filenames_for_search (obj->original_name, name))
+ {
+ objfile = obj;
+ return 1;
+ }
+
+ return 0;
+ }, gdbpy_current_objfile);

if (objfile != NULL)
return objfile_to_objfile_object (objfile).release ();
diff --git a/gdb/python/python.c b/gdb/python/python.c
index 9bef2252e88..ba6fdc455b7 100644
--- a/gdb/python/python.c
+++ b/gdb/python/python.c
@@ -1581,11 +1581,8 @@ gdbpy_current_language (PyObject *unused1, PyObject *unused2)

\f

-/* The "current" objfile. This is set when gdb detects that a new
- objfile has been loaded. It is only set for the duration of a call to
- gdbpy_source_objfile_script and gdbpy_execute_objfile_script; it is NULL
- at other times. */
-static struct objfile *gdbpy_current_objfile;
+/* See python.h. */
+struct objfile *gdbpy_current_objfile;

/* Set the current objfile to OBJFILE and then read FILE named FILENAME
as Python code. This does not throw any errors. If an exception
diff --git a/gdb/python/python.h b/gdb/python/python.h
index 4b150c36a9e..2be83ba2da6 100644
--- a/gdb/python/python.h
+++ b/gdb/python/python.h
@@ -28,4 +28,10 @@ extern const struct extension_language_defn extension_language_python;
/* Command element for the 'python' command. */
extern cmd_list_element *python_cmd_element;

+/* The "current" objfile. This is set when gdb detects that a new
+ objfile has been loaded. It is only set for the duration of a call to
+ gdbpy_source_objfile_script and gdbpy_execute_objfile_script; it is NULL
+ at other times. */
+extern struct objfile *gdbpy_current_objfile;
+
#endif /* PYTHON_PYTHON_H */
--
2.35.3