From 9f398ac406394bf35849f4de17c32e1765bfe30a Mon Sep 17 00:00:00 2001 From: brobecke Date: Wed, 6 Jan 2010 12:46:18 +0000 Subject: [PATCH] New python script adding pretty printers for types defined in GDB. * gdb-gdb.py: New file. --- gdb/ChangeLog | 4 + gdb/gdb-gdb.py | 241 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 245 insertions(+) create mode 100644 gdb/gdb-gdb.py diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 1a5bafc668..4ba426e8dd 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,7 @@ +2010-01-06 Joel Brobecker + + * gdb-gdb.py: New file. + 2010-01-05 Michael Snyder * infrun.c (handle_inferior_event): Fix typo in comment. diff --git a/gdb/gdb-gdb.py b/gdb/gdb-gdb.py new file mode 100644 index 0000000000..49695b54be --- /dev/null +++ b/gdb/gdb-gdb.py @@ -0,0 +1,241 @@ +# Copyright (C) 2009, 2010 Free Software Foundation, Inc. +# +# This file is part of GDB. +# +# 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 . + +import gdb +import os.path + +class TypeFlag: + """A class that allows us to store a flag name, its short name, + and its value. + + In the GDB sources, struct type has a component called instance_flags + whose the value is the addition of various flags. These flags are + defined by two emumerates: type_flag_value, and type_instance_flag_value. + This class helps us recreate a list with all these flags that is + easy to manipulate and sort. Because all flag names start with either + TYPE_FLAG_ or TYPE_INSTANCE_FLAG_, a short_name attribute is provided + that strips this prefix. + + ATTRIBUTES + name: The enumeration name (eg: "TYPE_FLAG_UNSIGNED"). + value: The associated value. + short_name: The enumeration name, with the suffix stripped. + """ + def __init__(self, name, value): + self.name = name + self.value = value + self.short_name = name.replace("TYPE_FLAG_", '') + if self.short_name == name: + self.short_name = name.replace("TYPE_INSTANCE_FLAG_", '') + def __cmp__(self, other): + """Sort by value order.""" + return self.value.__cmp__(other.value) + +# A list of all existing TYPE_FLAGS_* and TYPE_INSTANCE_FLAGS_* +# enumerations, stored as TypeFlags objects. Lazy-initialized. +TYPE_FLAGS = None + +class TypeFlagsPrinter: + """A class that prints a decoded form of an instance_flags value. + + This class uses a global named TYPE_FLAGS, which is a list of + all defined TypeFlag values. Using a global allows us to compute + this list only once. + + This class relies on a couple of enumeration types being defined. + If not, then printing of the instance_flag is going to be degraded, + but it's not a fatal error. + """ + def __init__(self, val): + self.val = val + def __str__(self): + global TYPE_FLAGS + if TYPE_FLAGS is None: + self.init_TYPE_FLAGS() + if not self.val: + return "0" + if TYPE_FLAGS: + flag_list = [flag.short_name for flag in TYPE_FLAGS + if self.val & flag.value] + else: + flag_list = ["???"] + return "0x%x [%s]" % (self.val, "|".join(flag_list)) + def init_TYPE_FLAGS(self): + """Initialize the TYPE_FLAGS global as a list of TypeFlag objects. + This operation requires the search of a couple of enumeration types. + If not found, a warning is printed on stdout, and TYPE_FLAGS is + set to the empty list. + + The resulting list is sorted by increasing value, to facilitate + printing of the list of flags used in an instance_flags value. + """ + global TYPE_FLAGS + TYPE_FLAGS = [] + try: + flags = gdb.lookup_type("enum type_flag_value") + except: + print "Warning: Cannot find enum type_flag_value type." + print " `struct type' pretty-printer will be degraded" + return + try: + iflags = gdb.lookup_type("enum type_instance_flag_value") + except: + print "Warning: Cannot find enum type_instance_flag_value type." + print " `struct type' pretty-printer will be degraded" + return + # Note: TYPE_FLAG_MIN is a duplicate of TYPE_FLAG_UNSIGNED, + # so exclude it from the list we are building. + TYPE_FLAGS = [TypeFlag(field.name, field.bitpos) + for field in flags.fields() + if field.name != 'TYPE_FLAG_MIN'] + TYPE_FLAGS += [TypeFlag(field.name, field.bitpos) + for field in iflags.fields()] + TYPE_FLAGS.sort() + +class StructTypePrettyPrinter: + """Pretty-print an object of type struct type""" + def __init__(self, val): + self.val = val + def to_string(self): + fields = [] + fields.append("pointer_type = %s" % self.val['pointer_type']) + fields.append("reference_type = %s" % self.val['reference_type']) + fields.append("chain = %s" % self.val['reference_type']) + fields.append("instance_flags = %s" + % TypeFlagsPrinter(self.val['instance_flags'])) + fields.append("length = %d" % self.val['length']) + fields.append("main_type = %s" % self.val['main_type']) + return "\n{" + ",\n ".join(fields) + "}" + +class StructMainTypePrettyPrinter: + """Pretty-print an objet of type main_type""" + def __init__(self, val): + self.val = val + def flags_to_string(self): + """struct main_type contains a series of components that + are one-bit ints whose name start with "flag_". For instance: + flag_unsigned, flag_stub, etc. In essence, these components are + really boolean flags, and this method prints a short synthetic + version of the value of all these flags. For instance, if + flag_unsigned and flag_static are the only components set to 1, + this function will return "unsigned|static". + """ + fields = [field.name.replace("flag_", "") + for field in self.val.type.fields() + if field.name.startswith("flag_") + and self.val[field.name]] + return "|".join(fields) + def owner_to_string(self): + """Return an image of component "owner". + """ + if self.val['flag_objfile_owned'] != 0: + return "%s (objfile)" % self.val['owner']['objfile'] + else: + return "%s (gdbarch)" % self.val['owner']['gdbarch'] + def struct_field_location_img(self, field_val): + """Return an image of the loc component inside the given field + gdb.Value. + """ + loc_val = field_val['loc'] + loc_kind = str(field_val['loc_kind']) + if loc_kind == "FIELD_LOC_KIND_BITPOS": + return 'bitpos = %d' % loc_val['bitpos'] + elif loc_kind == "FIELD_LOC_KIND_PHYSADDR": + return 'physaddr = 0x%x' % loc_val['physaddr'] + elif loc_kind == "FIELD_LOC_KIND_PHYSNAME": + return 'physname = %s' % loc_val['physname'] + elif loc_kind == "FIELD_LOC_KIND_DWARF_BLOCK": + return 'dwarf_block = %s' % loc_val['dwarf_block'] + else: + return 'loc = ??? (unsupported loc_kind value)' + def struct_field_img(self, fieldno): + """Return an image of the main_type field number FIELDNO. + """ + f = self.val['flds_bnds']['fields'][fieldno] + label = "field[%d]:" % fieldno + if f['artificial']: + label += " (artificial)" + fields = [] + fields.append("name = %s" % f['name']) + fields.append("type = %s" % f['type']) + fields.append("loc_kind = %s" % f['loc_kind']) + fields.append("bitsize = %d" % f['bitsize']) + fields.append(self.struct_field_location_img(f)) + return label + "\n" + " {" + ",\n ".join(fields) + "}" + def bounds_img(self): + """Return an image of the main_type bounds. + """ + b = self.val['flds_bnds']['bounds'].dereference() + low = str(b['low']) + if b['low_undefined'] != 0: + low += " (undefined)" + high = str(b['high']) + if b['high_undefined'] != 0: + high += " (undefined)" + return "bounds = {%s, %s}" % (low, high) + def to_string(self): + """Return a pretty-printed image of our main_type. + """ + fields = [] + fields.append("name = %s" % self.val['name']) + fields.append("tag_name = %s" % self.val['tag_name']) + fields.append("code = %s" % self.val['code']) + fields.append("flags = [%s]" % self.flags_to_string()) + fields.append("owner = %s" % self.owner_to_string()) + fields.append("target_type = %s" % self.val['target_type']) + fields.append("vptr_basetype = %s" % self.val['vptr_basetype']) + if self.val['nfields'] > 0: + for fieldno in range(self.val['nfields']): + fields.append("field[%d]:") + fields.append(self.struct_field_img(fieldno)) + if self.val.type.code == gdb.TYPE_CODE_RANGE: + fields.append(self.bounds_img()) + # FIXME: We need to print the type_specific field as well. + # But I will wait for a patch that introduces a discriminant. + # This will simplify the selection of the right component in + # that union. + return "\n{" + ",\n ".join(fields) + "}" + +def type_lookup_function(val): + """A routine that returns the correct pretty printer for VAL + if appropriate. Returns None otherwise. + """ + if val.type.tag == "type": + return StructTypePrettyPrinter(val) + elif val.type.tag == "main_type": + return StructMainTypePrettyPrinter(val) + return None + +def register_pretty_printer(objfile): + """A routine to register a pretty-printer against the given OBJFILE. + """ + objfile.pretty_printers.append(type_lookup_function) + +if __name__ == "__main__": + if gdb.current_objfile() is not None: + # This is the case where this script is being "auto-loaded" + # for a given objfile. Register the pretty-printer for that + # objfile. + register_pretty_printer(gdb.current_objfile()) + else: + # We need to locate the objfile corresponding to the GDB + # executable, and register the pretty-printer for that objfile. + # FIXME: The condition used to match the objfile is too simplistic + # and will not work on Windows. + for objfile in gdb.objfiles(): + if os.path.basename(objfile.filename) == "gdb": + objfile.pretty_printers.append(type_lookup_function) -- 2.11.0