Pretty printing boost::unordered_map on gdb
recently I've started to use the excellent boost::unordered_map on my system, but got one drawback: I couldn't figure how to inspect its contents. Printing it on 开发者_运维问答gdb gives me a table_ and a buckets_, but haven't found where are the items. Anyone has a clue about this?
For the ones that wanted a printer, I've managed to create one. Here is Code:
class BoostUnorderedMapPrinter:
"prints a boost::unordered_map"
class _iterator:
def __init__ (self, fields):
type_1 = fields.val.type.template_argument(0)
type_2 = fields.val.type.template_argument(1)
self.buckets = fields.val['table_']['buckets_']
self.bucket_count = fields.val['table_']['bucket_count_']
self.current_bucket = 0
pair = "std::pair<%s const, %s>" % (type_1, type_2)
self.pair_pointer = gdb.lookup_type(pair).pointer()
self.base_pointer = gdb.lookup_type("boost::unordered_detail::value_base< %s >" % pair).pointer()
self.node_pointer = gdb.lookup_type("boost::unordered_detail::hash_node<std::allocator< %s >, boost::unordered_detail::ungrouped>" % pair).pointer()
self.node = self.buckets[self.current_bucket]['next_']
def __iter__(self):
return self
def next(self):
while not self.node:
self.current_bucket = self.current_bucket + 1
if self.current_bucket >= self.bucket_count:
raise StopIteration
self.node = self.buckets[self.current_bucket]['next_']
iterator = self.node.cast(self.node_pointer).cast(self.base_pointer).cast(self.pair_pointer).dereference()
self.node = self.node['next_']
return ('%s' % iterator['first'], iterator['second'])
def __init__(self, val):
self.val = val
def children(self):
return self._iterator(self)
def to_string(self):
return "boost::unordered_map"
In a typical hash table implementation, the buckets contain the head of a linked list which actually contains the values corresponding to this particular hash. Thus I would bet on buckets_
.
Another option: there are various python pretty printer libraries for gdb now, and I think that you could find one that works with C++0x and inspect where it looks for the values.
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