[RFA/python+doco/NEWS] Add gdb.Type.name attribute.

[Joel Brobecker <brobecker at adacore dot com>]

Hello,

Consider the following declarations:

    typedef long our_time_t;
    our_time_t current_time = 1384395743;

The purpose of this patch is to allow the use of a pretty-printer
for variables of type our_time_t.  Normally, pretty-printing sniffers
use the tag name in order to determine which, if any, pretty-printer
should be used. But in the case above, the tag name is not set, since
it does not apply to integral types.

This patch extends the gdb.Type list of attributes to also include
the name of the type, thus allowing the sniffer to match against
that name. With that change, I was able to write a pretty-printer
which displays our variable as follow:

    (gdb) print current_time
    $1 = Thu Nov 14 02:22:23 2013 (1384395743)

gdb/ChangeLog:

        * python/py-type.c (typy_get_name): New function.
        (type_object_getset): Add entry for attribute "name".
        * NEWS: Add entry mentioning this new attribute.

gdb/doc/ChangeLog:

        * gdb.texinfo (Types In Python): Document new attribute Types.name.

gdb/testsuite/gdb.python:

        * py-pp-integral.c: New file.
        * py-pp-integral.py: New file.
        * py-pp-integral.exp: New file.

Tested on x86_64-linux. OK to commit?

Thank you!
-- 
Joel

---
 gdb/NEWS                                    |  1 +
 gdb/doc/gdb.texinfo                         |  5 ++++
 gdb/python/py-type.c                        | 14 +++++++++++
 gdb/testsuite/gdb.python/py-pp-integral.c   | 33 +++++++++++++++++++++++++
 gdb/testsuite/gdb.python/py-pp-integral.exp | 38 +++++++++++++++++++++++++++++
 gdb/testsuite/gdb.python/py-pp-integral.py  | 35 ++++++++++++++++++++++++++
 6 files changed, 126 insertions(+)
 create mode 100644 gdb/testsuite/gdb.python/py-pp-integral.c
 create mode 100644 gdb/testsuite/gdb.python/py-pp-integral.exp
 create mode 100644 gdb/testsuite/gdb.python/py-pp-integral.py

diff --git a/gdb/NEWS b/gdb/NEWS
index e4baf50..5fac44a 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -42,6 +42,7 @@
   ** Line tables representation has been added.
   ** New attribute 'parent_type' for gdb.Field objects.
   ** gdb.Field objects can be used as subscripts on gdb.Value objects.
+  ** New attribute 'name' for gdb.Type objects.
 
 * New targets
 
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 29f1cfc..2c8e4bc 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -24324,6 +24324,11 @@ The type code for this type.  The type code will be one of the
 @code{TYPE_CODE_} constants defined below.
 @end defvar
 
+@defvar Type.name
+The name of this type.  If this type has no name, then @code{None}
+is returned.
+@end defvar
+
 @defvar Type.sizeof
 The size of this type, in target @code{char} units.  Usually, a
 target's @code{char} type will be an 8-bit byte.  However, on some
diff --git a/gdb/python/py-type.c b/gdb/python/py-type.c
index 4ad1e12..a70dcfd 100644
--- a/gdb/python/py-type.c
+++ b/gdb/python/py-type.c
@@ -414,6 +414,18 @@ typy_items (PyObject *self, PyObject *args)
   return typy_fields_items (self, iter_items);
 }
 
+/* Return the type's name, or None.  */
+
+static PyObject *
+typy_get_name (PyObject *self, void *closure)
+{
+  struct type *type = ((type_object *) self)->type;
+
+  if (TYPE_NAME (type) == NULL)
+    Py_RETURN_NONE;
+  return PyString_FromString (TYPE_NAME (type));
+}
+
 /* Return the type's tag, or None.  */
 static PyObject *
 typy_get_tag (PyObject *self, void *closure)
@@ -1395,6 +1407,8 @@ static PyGetSetDef type_object_getset[] =
 {
   { "code", typy_get_code, NULL,
     "The code for this type.", NULL },
+  { "name", typy_get_name, NULL,
+    "The name for this type, or None.", NULL },
   { "sizeof", typy_get_sizeof, NULL,
     "The size of this type, in bytes.", NULL },
   { "tag", typy_get_tag, NULL,
diff --git a/gdb/testsuite/gdb.python/py-pp-integral.c b/gdb/testsuite/gdb.python/py-pp-integral.c
new file mode 100644
index 0000000..39763e1
--- /dev/null
+++ b/gdb/testsuite/gdb.python/py-pp-integral.c
@@ -0,0 +1,33 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 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/>.  */
+
+typedef long time_t;
+
+static void
+tick_tock (time_t *t)
+{
+  *t++;
+}
+
+int
+main (void)
+{
+  time_t current_time = 1384395743;
+
+  tick_tock (&current_time);
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.python/py-pp-integral.exp b/gdb/testsuite/gdb.python/py-pp-integral.exp
new file mode 100644
index 0000000..4b49d99
--- /dev/null
+++ b/gdb/testsuite/gdb.python/py-pp-integral.exp
@@ -0,0 +1,38 @@
+# 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/>.
+
+standard_testfile
+
+if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile}] } {
+    return -1
+}
+
+# Skip all tests if Python scripting is not enabled.
+if { [skip_python_tests] } { continue }
+
+if ![runto tick_tock] {
+    return -1
+}
+
+set remote_python_file [gdb_remote_download host \
+			    ${srcdir}/${subdir}/${testfile}.py]
+
+gdb_test_no_output "source ${remote_python_file}"
+
+gdb_test "print *t" " = Thu Nov 14 02:22:23 2013 \\(1384395743\\)"
+
+gdb_test "print /r *t" "= 1384395743"
+
+remote_file host delete ${remote_python_file}
diff --git a/gdb/testsuite/gdb.python/py-pp-integral.py b/gdb/testsuite/gdb.python/py-pp-integral.py
new file mode 100644
index 0000000..9f4dd25
--- /dev/null
+++ b/gdb/testsuite/gdb.python/py-pp-integral.py
@@ -0,0 +1,35 @@
+# 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/>.
+
+from time import asctime, gmtime
+import gdb  # silence pyflakes
+
+
+class TimePrinter:
+    def __init__(self, val):
+        self.val = val
+
+    def to_string(self):
+        secs = int(self.val)
+        return "%s (%d)" % (asctime(gmtime(secs)), secs)
+
+
+def time_sniffer(val):
+    if hasattr(val.type, 'name') and val.type.name == "time_t":
+        return TimePrinter(val)
+    return None
+
+
+gdb.pretty_printers.append(time_sniffer)
-- 
1.8.3.2