projects / apple / xnu.git / blame
| Commit | Line | Data |
|---|---|---|
| fe8ab488 A |
1 | import lldb |
| 2 | from xnu import * | |
| 3 | ||
| 4 | def _showStructPacking(symbol, prefix, begin_offset=0): | |
| 5 | """ | |
| 6 | recursively parse the field members of structure. | |
| 7 | params : symbol (lldb.SBType) reference to symbol in binary | |
| 8 | prefix (string) string to be prefixed for each line of output. Useful for recursive struct parsing. | |
| 9 | returns: string containing lines of output. | |
| 10 | """ | |
| 11 | ctype = "unknown type" | |
| 12 | if symbol.GetTypeClass() == lldb.eTypeClassUnion : | |
| 13 | ctype = "union" | |
| 14 | if symbol.GetTypeClass() == lldb.eTypeClassStruct : | |
| 15 | ctype = "struct" | |
| 16 | outstr = "[%4d] (%s) %s { " % (symbol.GetByteSize(), ctype, symbol.GetName()) + "\n" | |
| 17 | numFields = symbol.GetNumberOfFields() | |
| 18 | _has_memory_hole = False | |
| 19 | _compact_size = 0 # asuming the struct is perfectly packed | |
| 20 | _compact_offset = begin_offset | |
| 21 | _previous_bit_offset = 0 | |
| 22 | for i in range(numFields): | |
| 23 | member = symbol.GetFieldAtIndex(i) | |
| 24 | m_offset = member.GetOffsetInBytes() + begin_offset | |
| 25 | m_offset_bits = member.GetOffsetInBits() | |
| 26 | m_type = member.GetType() | |
| 27 | m_name = member.GetName() | |
| 28 | m_size = m_type.GetByteSize() | |
| 29 | warningstr = "" | |
| 30 | debugstr = "" # + str((m_size, m_offset , m_offset_bits, _previous_bit_offset, _compact_offset, begin_offset)) | |
| 31 | if _compact_offset != m_offset and (m_offset_bits - _previous_bit_offset) > m_size*8 : | |
| 32 | _has_memory_hole = True | |
| 33 | warningstr = " *** Possible memory hole ***" | |
| 34 | _compact_offset = m_offset | |
| 35 | _compact_offset += m_size | |
| 36 | if m_type.GetTypeClass() == lldb.eTypeClassStruct or m_type.GetTypeClass() == lldb.eTypeClassUnion : | |
| 37 | outstr += prefix + ("*%4d," % m_offset) + _showStructPacking(m_type, prefix+" ", m_offset) + warningstr + debugstr + "\n" | |
| 38 | else: | |
| 39 | outstr += prefix + ("+%4d,[%4d] (%s) %s" % (m_offset, m_size, m_type.GetName(), m_name)) + warningstr + debugstr + "\n" | |
| 40 | if i > 0 : | |
| 41 | _previous_bit_offset = m_offset_bits | |
| 42 | outstr += prefix + "}" | |
| 43 | if _has_memory_hole == True : | |
| 44 | outstr += " *** Warning: Struct layout leaves memory hole *** " | |
| 45 | return outstr | |
| 46 | ||
| 47 | @lldb_command('showstructpacking') | |
| 48 | def showStructInfo(cmd_args=None): | |
| 49 | """Show how a structure is packed in the binary. The format is | |
| 50 | +<offset>, [<size_of_member>] (<type>) <name> | |
| 51 | For example: | |
| 52 | (lldb) script lldbmacros.showStructInfo("pollfd") | |
| 53 | [ 8] (struct) pollfd { | |
| 54 | + 0,[ 4] (int) fd | |
| 55 | + 4,[ 2] (short) events | |
| 56 | + 6,[ 2] (short) revents | |
| 57 | } | |
| 58 | syntax: showstructpacking task | |
| 59 | """ | |
| 60 | if not cmd_args: | |
| 61 | raise ArgumentError("Please provide a type name.") | |
| 62 | ||
| 63 | sym = gettype(cmd_args[0]) | |
| 64 | if sym == None: | |
| 65 | print "No such struct found" | |
| 66 | if sym.GetTypeClass() == lldb.eTypeClassTypedef: | |
| 67 | sym = sym.GetCanonicalType() | |
| 68 | if sym.GetTypeClass() != lldb.eTypeClassStruct: | |
| 69 | print "%s is not a structure" % cmd_args[0] | |
| 70 | else: | |
| 71 | print _showStructPacking(sym,"", 0) | |
| 72 | ||
| 73 | # EndMacro: showstructinto |