commit 21909fa1c6d934bfa0c7ad3ef95909db48f6f756

Author: Tom Tromey <tromey@redhat.com>

Date:   Wed Jan 22 08:10:01 2014 -0700

    fix crash in frame filters

    apply_frame_filter calls ensure_python_env before computing the

    gdbarch to use.  This means that python_gdbarch can be NULL while in

    Python code, and if a frame filter depends on this somehow (easy to

    do), gdb will crash.

    The fix is to compute the gdbarch first.

    Built and regtested on x86-64 Fedora 18.

    New test case included.

    2014-01-23  Tom Tromey  <tromey@redhat.com>

    	PR python/16491:

    	* python/py-framefilter.c (apply_frame_filter): Call

    	ensure_python_env after computing gdbarch.

    2014-01-23  Tom Tromey  <tromey@redhat.com>

    	PR python/16491:

    	* gdb.python/py-framefilter.py (Reverse_Function.function): Read a

    	string from an inferior frame.

    	* gdb.python/py-framefilter-mi.exp: Update.

Index: gdb-7.6.1/gdb/python/py-framefilter.c

===================================================================

--- gdb-7.6.1.orig/gdb/python/py-framefilter.c

+++ gdb-7.6.1/gdb/python/py-framefilter.c

@@ -1468,18 +1468,18 @@ apply_frame_filter (struct frame_info *f

   PyObject *item;

   htab_t levels_printed;

-  cleanups = ensure_python_env (gdbarch, current_language);

-

   TRY_CATCH (except, RETURN_MASK_ALL)

     {

       gdbarch = get_frame_arch (frame);

     }

   if (except.reason < 0)

     {

-      gdbpy_convert_exception (except);

-      goto error;

+      /* Let gdb try to print the stack trace.  */

+      return PY_BT_NO_FILTERS;

     }

+  cleanups = ensure_python_env (gdbarch, current_language);

+

   iterable = bootstrap_python_frame_filters (frame, frame_low, frame_high);

   if (iterable == NULL)

Index: gdb-7.6.1/gdb/testsuite/gdb.python/py-framefilter-mi.exp

===================================================================

--- gdb-7.6.1.orig/gdb/testsuite/gdb.python/py-framefilter-mi.exp

+++ gdb-7.6.1/gdb/testsuite/gdb.python/py-framefilter-mi.exp

@@ -66,10 +66,10 @@ mi_continue_to_line [gdb_get_line_number

   "step to breakpoint"

 mi_gdb_test "-stack-list-frames" \

-    "\\^done,stack=\\\[frame={level=\"0\",addr=\"$hex\",func=\"cnuf_dne\".*},frame={level=\"1\",addr=\"$hex\",func=\"acnuf\".*},frame={level=\"2\",addr=\"$hex\",func=\"bcnuf\".*},frame={level=\"3\",addr=\"$hex\",func=\"acnuf\".*},frame={level=\"22\",addr=\"$hex\",func=\"1cnuf\".*,children=\\\[frame={level=\"23\",addr=\"$hex\",func=\"func2\".*}\\\]},frame={level=\"24\",addr=\"$hex\",func=\"3cnuf\".*},frame={level=\"27\",addr=\"$hex\",func=\"niam\".*}\\\].*" \

+    "\\^done,stack=\\\[frame={level=\"0\",addr=\"$hex\",func=\"cnuf_dne.*\".*},frame={level=\"1\",addr=\"$hex\",func=\"acnuf\".*},frame={level=\"2\",addr=\"$hex\",func=\"bcnuf\".*},frame={level=\"3\",addr=\"$hex\",func=\"acnuf\".*},frame={level=\"22\",addr=\"$hex\",func=\"1cnuf\".*,children=\\\[frame={level=\"23\",addr=\"$hex\",func=\"func2\".*}\\\]},frame={level=\"24\",addr=\"$hex\",func=\"3cnuf\".*},frame={level=\"27\",addr=\"$hex\",func=\"niam\".*}\\\].*" \

     "filtered stack listing"

 mi_gdb_test "-stack-list-frames 0 3" \

-    "\\^done,stack=\\\[frame={level=\"0\",addr=\"$hex\",func=\"cnuf_dne\".*},frame={level=\"1\",addr=\"$hex\",func=\"acnuf\".*},frame={level=\"2\",addr=\"$hex\",func=\"bcnuf\".*},frame={level=\"3\",addr=\"$hex\",func=\"acnuf\".*}\\\]" \

+    "\\^done,stack=\\\[frame={level=\"0\",addr=\"$hex\",func=\"cnuf_dne.*\".*},frame={level=\"1\",addr=\"$hex\",func=\"acnuf\".*},frame={level=\"2\",addr=\"$hex\",func=\"bcnuf\".*},frame={level=\"3\",addr=\"$hex\",func=\"acnuf\".*}\\\]" \

     "filtered stack list 0 3"

 mi_gdb_test "-stack-list-frames 22 24" \

     "\\^done,stack=\\\[frame={level=\"22\",addr=\"$hex\",func=\"1cnuf\".*,children=\\\[frame={level=\"23\",addr=\"$hex\",func=\"func2\".*}\\\]},frame={level=\"24\",addr=\"$hex\",func=\"3cnuf\".*}\\\]" \

Index: gdb-7.6.1/gdb/testsuite/gdb.python/py-framefilter.py

===================================================================

--- gdb-7.6.1.orig/gdb/testsuite/gdb.python/py-framefilter.py

+++ gdb-7.6.1/gdb/testsuite/gdb.python/py-framefilter.py

@@ -30,8 +30,11 @@ class Reverse_Function (FrameDecorator):

         fname = str (self.fobj.function())

         if (fname == None or fname == ""):

             return None

+        if fname == 'end_func':

+            extra = self.fobj.inferior_frame().read_var('str').string()

         else:

-            fname = fname[::-1]

+            extra = ''

+        fname = fname[::-1] + extra

         return fname

 class Dummy (FrameDecorator):

Index: gdb-7.6.1/gdb/testsuite/gdb.python/rhbz1197665-apply-frame-filter-segv-gdb.py.in

===================================================================

--- /dev/null

+++ gdb-7.6.1/gdb/testsuite/gdb.python/rhbz1197665-apply-frame-filter-segv-gdb.py.in

@@ -0,0 +1,48 @@

+# Copyright (C) 2013 Free Software Foundation, Inc.

+

+# This program is free software; you can redistribute it and/or modify

+# it under the terms of the GNU General Public License as published by

+# the Free Software Foundation; either version 3 of the License, or

+# (at your option) any later version.

+#

+# This program is distributed in the hope that it will be useful,

+# but WITHOUT ANY WARRANTY; without even the implied warranty of

+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+# GNU General Public License for more details.

+#

+# You should have received a copy of the GNU General Public License

+# along with this program.  If not, see <http://www.gnu.org/licenses/>.

+

+# This file is part of the GDB testsuite.  It tests Python-based

+# frame-filters.

+import gdb

+import itertools

+from gdb.FrameDecorator import FrameDecorator

+

+

+class FrameObjFile ():

+

+    def __init__ (self):

+        self.name = "Filter1"

+        self.priority = 1

+        self.enabled = False

+        gdb.current_progspace().frame_filters ["Progspace" + self.name] = self

+        gdb.current_objfile().frame_filters ["ObjectFile" + self.name] = self

+

+    def filter (self, frame_iter):

+        return frame_iter

+

+class FrameObjFile2 ():

+

+    def __init__ (self):

+        self.name = "Filter2"

+        self.priority = 100

+        self.enabled = True

+        gdb.current_progspace().frame_filters ["Progspace" + self.name] = self

+        gdb.current_objfile().frame_filters ["ObjectFile" + self.name] = self

+

+    def filter (self, frame_iter):

+        return frame_iter

+

+FrameObjFile()

+FrameObjFile2()

Index: gdb-7.6.1/gdb/testsuite/gdb.python/rhbz1197665-apply-frame-filter-segv.exp

===================================================================

--- /dev/null

+++ gdb-7.6.1/gdb/testsuite/gdb.python/rhbz1197665-apply-frame-filter-segv.exp

@@ -0,0 +1,76 @@

+# Copyright (C) 2013-2015 Free Software Foundation, Inc.

+

+# This program is free software; you can redistribute it and/or modify

+# it under the terms of the GNU General Public License as published by

+# the Free Software Foundation; either version 3 of the License, or

+# (at your option) any later version.

+#

+# This program is distributed in the hope that it will be useful,

+# but WITHOUT ANY WARRANTY; without even the implied warranty of

+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+# GNU General Public License for more details.

+#

+# You should have received a copy of the GNU General Public License

+# along with this program.  If not, see <http://www.gnu.org/licenses/>.

+

+# This file is part of the GDB testsuite.  It tests Python-based

+# frame-filters.

+

+# This test is specifically crafted for RH BZ 1197665.

+

+load_lib gdb-python.exp

+

+standard_testfile py-framefilter.c

+

+# We cannot use prepare_for_testing as we have to set the safe-patch

+# to check objfile and progspace printers.

+if {[build_executable $testfile.exp $testfile $srcfile debug] == -1} {

+    return -1

+}

+

+# Start with a fresh gdb.

+gdb_exit

+gdb_start

+

+# Skip all tests if Python scripting is not enabled.

+if { [skip_python_tests] } { continue }

+

+# Make the -gdb.py script available to gdb, it is automagically loaded by gdb.

+# Care is taken to put it in the same directory as the binary so that

+# gdb will find it.

+set remote_obj_python_file \

+    [remote_download \

+	 host ${srcdir}/${subdir}/${testfile}-gdb.py.in \

+	 ${subdir}/${testfile}-gdb.py]

+

+gdb_reinitialize_dir $srcdir/$subdir

+gdb_test_no_output "set auto-load safe-path ${remote_obj_python_file}" \

+    "set auto-load safe-path"

+gdb_load ${binfile}

+# Verify gdb loaded the script.

+gdb_test "info auto-load python-scripts" "Yes.*/${testfile}-gdb.py.*" \

+    "Test auto-load had loaded python scripts"

+

+if ![runto_main] then {

+    perror "couldn't run to breakpoint"

+    return

+}

+gdb_test_no_output "set python print-stack full" \

+    "Set python print-stack to full"

+

+# Load global frame-filters

+set remote_python_file [remote_download host ${srcdir}/${subdir}/${testfile}.py]

+gdb_test_no_output "python execfile ('${remote_python_file}')" \

+    "Load python file"

+

+gdb_breakpoint [gdb_get_line_number "Backtrace end breakpoint"]

+gdb_breakpoint [gdb_get_line_number "Inner test breakpoint"]

+gdb_continue_to_breakpoint "Inner test breakpoint"

+

+# Test multiple local blocks.

+gdb_test "bt full no-filters" \

+    ".*#0.*end_func.*h = 9.*f = 42.*g = 19.*bar = $hex \"Inside block x2\".*d = 15.*e = 14.*foo = $hex \"Inside block\".*str = $hex \"The End\".*st2 = $hex \"Is Near\".*b = 12.*c = 5.*" \

+    "bt full no-filters"

+gdb_test "bt full" \

+    ".*#0.*cnuf_dne.*h = 9.*f = 42.*g = 19.*bar = $hex \"Inside block x2\".*d = 15.*e = 14.*foo = $hex \"Inside block\".*str = $hex \"The End\".*st2 = $hex \"Is Near\".*b = 12.*c = 5.*" \

+    "bt full with filters"

Index: gdb-7.6.1/gdb/testsuite/gdb.python/rhbz1197665-apply-frame-filter-segv.py

===================================================================

--- /dev/null

+++ gdb-7.6.1/gdb/testsuite/gdb.python/rhbz1197665-apply-frame-filter-segv.py

@@ -0,0 +1,56 @@

+# Copyright (C) 2013-2015 Free Software Foundation, Inc.

+

+# This program is free software; you can redistribute it and/or modify

+# it under the terms of the GNU General Public License as published by

+# the Free Software Foundation; either version 3 of the License, or

+# (at your option) any later version.

+#

+# This program is distributed in the hope that it will be useful,

+# but WITHOUT ANY WARRANTY; without even the implied warranty of

+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+# GNU General Public License for more details.

+#

+# You should have received a copy of the GNU General Public License

+# along with this program.  If not, see <http://www.gnu.org/licenses/>.

+

+# This file is part of the GDB testsuite.  It tests Python-based

+# frame-filters.

+

+# This test is specifically crafted for RH BZ 1197665.

+

+import gdb

+import itertools

+from gdb.FrameDecorator import FrameDecorator

+import copy

+

+class Reverse_Function (FrameDecorator):

+

+    def __init__(self, fobj):

+        super(Reverse_Function, self).__init__(fobj)

+        self.fobj = fobj

+

+    def function (self):

+        # This function call should not fail.

+        gdb.target_charset ()

+

+        fname = str (self.fobj.function())

+        if (fname == None or fname == ""):

+            return None

+        else:

+            fname = fname[::-1]

+        return fname

+

+class FrameFilter ():

+

+    def __init__ (self):

+        self.name = "Reverse"

+        self.priority = 100

+        self.enabled = True

+        gdb.frame_filters [self.name] = self

+

+    def filter (self, frame_iter):

+        frame_iter = itertools.imap (Reverse_Function,

+                                     frame_iter)

+        return frame_iter

+

+FrameFilter()