call frame instructions parsing kinda done. now need to run some tests: ++ write unit tests for this
diff --git a/elftools/dwarf/callframe.py b/elftools/dwarf/callframe.py
index 280caa4..e352e52 100644
--- a/elftools/dwarf/callframe.py
+++ b/elftools/dwarf/callframe.py
@@ -6,8 +6,37 @@
# Eli Bendersky (eliben@gmail.com)
# This code is in the public domain
#-------------------------------------------------------------------------------
-from ..common.utils import (struct_parse)
+from collections import namedtuple
+
+from ..common.utils import (struct_parse, dwarf_assert)
from .structs import DWARFStructs
+from .constants import *
+
+
+CallFrameInstruction = namedtuple(
+ 'CallFrameInstruction', 'opcode args')
+
+
+class CIE(object):
+ def __init__(self, header, instructions):
+ self.header = header
+ self.instructions = instructions
+
+ def __getitem__(self, name):
+ """ Implement dict-like access to header entries
+ """
+ return self.header[name]
+
+
+class FDE(object):
+ def __init__(self, header, instructions):
+ self.header = header
+ self.instructions = instructions
+
+ def __getitem__(self, name):
+ """ Implement dict-like access to header entries
+ """
+ return self.header[name]
class CallFrameInfo(object):
@@ -17,8 +46,11 @@
self.base_structs = base_structs
def _parse_entries(self):
+ entries = []
offset = 0
while offset < self.size:
+ # Throughout the body of this loop, offset keeps pointing to the
+ # beginning of the entry
entry_length = struct_parse(
self.base_structs.Dwarf_uint32(''), self.stream, offset)
dwarf_format = 64 if entry_length == 0xFFFFFFFF else 32
@@ -28,8 +60,95 @@
dwarf_format=dwarf_format,
address_size=self.base_structs.address_size)
- # ZZZ: it will be easier to split entry reading:
- # header: what comes before the instructions
- # the instructions are parsed separately (their length is computed
- # from the length and the tell() after parsing the header)
+ # Read the next field to see whether this is a CIE or FDE
+ CIE_id = struct_parse(
+ entry_structs.Dwarf_offset('').parse, self.stream)
+
+ is_CIE = (
+ dwarf_format == 32 and CIE_id = 0xFFFFFFFF or
+ CIE_id == 0xFFFFFFFFFFFFFFFF)
+
+ if is_CIE:
+ header_struct = self.Dwarf_CIE_header
+ else:
+ header_struct = self.Dwarf_FDE_header
+
+ # Parse the header, which goes up to and including the
+ # return_address_register field
+ header = struct_parse(
+ header_struct, self.stream, offset)
+
+ # For convenience, compute the end offset for this entry
+ end_offset = (
+ offset + header.length - structs.initial_length_field_size())
+
+ # At this point self.stream is at the start of the instruction list
+ # for this entry
+ instructions = self._parse_instructions(
+ structs, self.stream.tell(), end_offset)
+
+ # ZZZ: for FDE's, I need some offset->CIE mapping cache stored
+
+ def _parse_instructions(self, structs, offset, end_offset):
+ """ Parse a list of CFI instructions from self.stream, starting with
+ the offset and until (not including) end_offset.
+ Return a list of CallFrameInstruction objects.
+ """
+ instructions = []
+ while offset < end_offset:
+ opcode = struct_parse(structs.Dwarf_uint8(''), self.stream, offset)
+ args = []
+
+ primary = opcode & 0b11000000
+ primary_arg = opcode & 0b00111111
+ if primary == DW_CFA_advance_loc:
+ args = [primary_arg]
+ elif primary == DW_CFA_offset:
+ args = [
+ primary_arg,
+ struct_parse(structs.Dwarf_uleb128(''), self.stream)]
+ elif primary == DW_CFA_restore:
+ args = [primary_arg]
+ # primary == 0 and real opcode is extended
+ elif opcode in (DW_CFA_nop, DW_CFA_remember_state,
+ DW_CFA_restore_state):
+ args = []
+ elif opcode == DW_CFA_set_loc:
+ args = [
+ struct_parse(structs.Dwarf_target_addr(''), self.stream)]
+ elif opcode == DW_CFA_advance_loc1:
+ args = [struct_parse(structs.Dwarf_uint8(''), self.stream)]
+ elif opcode == DW_CFA_advance_loc2:
+ args = [struct_parse(structs.Dwarf_uint16(''), self.stream)]
+ elif opcode == DW_CFA_advance_loc4:
+ args = [struct_parse(structs.Dwarf_uint32(''), self.stream)]
+ elif opcode in (DW_CFA_offset_extended, DW_CFA_register,
+ DW_CFA_def_cfa, DW_CFA_val_offset):
+ args = [
+ struct_parse(structs.Dwarf_uleb128(''), self.stream),
+ struct_parse(structs.Dwarf_uleb128(''), self.stream)]
+ elif opcode in (DW_CFA_restore_extended, DW_CFA_undefined,
+ DW_CFA_same_value, DW_CFA_def_cfa_register,
+ DW_CFA_def_cfa_offset):
+ args = [struct_parse(structs.Dwarf_uleb128(''), self.stream)]
+ elif opcode == DW_CFA_def_cfa_offset_sf:
+ args = [struct_parse(structs.Dwarf_sleb128(''), self.stream)]
+ elif opcode == DW_CFA_def_cfa_expression:
+ args = [struct_parse(
+ structs.Dwarf_dw_form['DW_FORM_block'], self.stream)]
+ elif opcode in (DW_CFA_expression, DW_CFA_val_expression):
+ arsg = [
+ struct_parse(structs.Dwarf_uleb128(''), self.stream),
+ struct_parse(
+ structs.Dwarf_dw_form['DW_FORM_block'], self.stream)]
+ elif opcode in (DW_CFA_offset_extended_sf,
+ DW_CFA_def_cfa_sf, DW_CFA_val_offset_sf):
+ args = [
+ struct_parse(structs.Dwarf_uleb128(''), self.stream),
+ struct_parse(structs.Dwarf_sleb128(''), self.stream)]
+ else:
+ dwarf_assert(False, 'Unknown CFI opcode: %s' % opcode)
+
+ instructions.append(CallFrameInstruction(opcode=opcode, args=args))
+ offset = self.stream.tell()
diff --git a/elftools/dwarf/constants.py b/elftools/dwarf/constants.py
index ae7e6b2..745bd6d 100644
--- a/elftools/dwarf/constants.py
+++ b/elftools/dwarf/constants.py
@@ -9,113 +9,113 @@
# Inline codes
#
-DW_INL_not_inlined=0
-DW_INL_inlined=1
-DW_INL_declared_not_inlined=2
-DW_INL_declared_inlined=3
+DW_INL_not_inlined = 0
+DW_INL_inlined = 1
+DW_INL_declared_not_inlined = 2
+DW_INL_declared_inlined = 3
# Source languages
#
-DW_LANG_C89=0x0001
-DW_LANG_C=0x0002
-DW_LANG_Ada83=0x0003
-DW_LANG_C_plus_plus=0x0004
-DW_LANG_Cobol74=0x0005
-DW_LANG_Cobol85=0x0006
-DW_LANG_Fortran77=0x0007
-DW_LANG_Fortran90=0x0008
-DW_LANG_Pascal83=0x0009
-DW_LANG_Modula2=0x000a
-DW_LANG_Java=0x000b
-DW_LANG_C99=0x000c
-DW_LANG_Ada95=0x000d
-DW_LANG_Fortran95=0x000e
-DW_LANG_PLI=0x000f
-DW_LANG_ObjC=0x0010
-DW_LANG_ObjC_plus_plus=0x0011
-DW_LANG_UPC=0x0012
-DW_LANG_D=0x0013
-DW_LANG_Python=0x0014
-DW_LANG_Mips_Assembler=0x8001
-DW_LANG_Upc=0x8765
-DW_LANG_HP_Bliss=0x8003
-DW_LANG_HP_Basic91=0x8004
-DW_LANG_HP_Pascal91=0x8005
-DW_LANG_HP_IMacro=0x8006
-DW_LANG_HP_Assembler=0x8007
+DW_LANG_C89 = 0x0001
+DW_LANG_C = 0x0002
+DW_LANG_Ada83 = 0x0003
+DW_LANG_C_plus_plus = 0x0004
+DW_LANG_Cobol74 = 0x0005
+DW_LANG_Cobol85 = 0x0006
+DW_LANG_Fortran77 = 0x0007
+DW_LANG_Fortran90 = 0x0008
+DW_LANG_Pascal83 = 0x0009
+DW_LANG_Modula2 = 0x000a
+DW_LANG_Java = 0x000b
+DW_LANG_C99 = 0x000c
+DW_LANG_Ada95 = 0x000d
+DW_LANG_Fortran95 = 0x000e
+DW_LANG_PLI = 0x000f
+DW_LANG_ObjC = 0x0010
+DW_LANG_ObjC_plus_plus = 0x0011
+DW_LANG_UPC = 0x0012
+DW_LANG_D = 0x0013
+DW_LANG_Python = 0x0014
+DW_LANG_Mips_Assembler = 0x8001
+DW_LANG_Upc = 0x8765
+DW_LANG_HP_Bliss = 0x8003
+DW_LANG_HP_Basic91 = 0x8004
+DW_LANG_HP_Pascal91 = 0x8005
+DW_LANG_HP_IMacro = 0x8006
+DW_LANG_HP_Assembler = 0x8007
# Encoding
#
-DW_ATE_void=0x0
-DW_ATE_address=0x1
-DW_ATE_boolean=0x2
-DW_ATE_complex_float=0x3
-DW_ATE_float=0x4
-DW_ATE_signed=0x5
-DW_ATE_signed_char=0x6
-DW_ATE_unsigned=0x7
-DW_ATE_unsigned_char=0x8
-DW_ATE_imaginary_float=0x9
-DW_ATE_packed_decimal=0xa
-DW_ATE_numeric_string=0xb
-DW_ATE_edited=0xc
-DW_ATE_signed_fixed=0xd
-DW_ATE_unsigned_fixed=0xe
-DW_ATE_decimal_float=0xf
-DW_ATE_UTF=0x10
-DW_ATE_lo_user=0x80
-DW_ATE_hi_user=0xff
-DW_ATE_HP_float80=0x80
-DW_ATE_HP_complex_float80=0x81
-DW_ATE_HP_float128=0x82
-DW_ATE_HP_complex_float128=0x83
-DW_ATE_HP_floathpintel=0x84
-DW_ATE_HP_imaginary_float80=0x85
-DW_ATE_HP_imaginary_float128=0x86
+DW_ATE_void = 0x0
+DW_ATE_address = 0x1
+DW_ATE_boolean = 0x2
+DW_ATE_complex_float = 0x3
+DW_ATE_float = 0x4
+DW_ATE_signed = 0x5
+DW_ATE_signed_char = 0x6
+DW_ATE_unsigned = 0x7
+DW_ATE_unsigned_char = 0x8
+DW_ATE_imaginary_float = 0x9
+DW_ATE_packed_decimal = 0xa
+DW_ATE_numeric_string = 0xb
+DW_ATE_edited = 0xc
+DW_ATE_signed_fixed = 0xd
+DW_ATE_unsigned_fixed = 0xe
+DW_ATE_decimal_float = 0xf
+DW_ATE_UTF = 0x10
+DW_ATE_lo_user = 0x80
+DW_ATE_hi_user = 0xff
+DW_ATE_HP_float80 = 0x80
+DW_ATE_HP_complex_float80 = 0x81
+DW_ATE_HP_float128 = 0x82
+DW_ATE_HP_complex_float128 = 0x83
+DW_ATE_HP_floathpintel = 0x84
+DW_ATE_HP_imaginary_float80 = 0x85
+DW_ATE_HP_imaginary_float128 = 0x86
# Access
#
-DW_ACCESS_public=1
-DW_ACCESS_protected=2
-DW_ACCESS_private=3
+DW_ACCESS_public = 1
+DW_ACCESS_protected = 2
+DW_ACCESS_private = 3
# Visibility
#
-DW_VIS_local=1
-DW_VIS_exported=2
-DW_VIS_qualified=3
+DW_VIS_local = 1
+DW_VIS_exported = 2
+DW_VIS_qualified = 3
# Virtuality
#
-DW_VIRTUALITY_none=0
-DW_VIRTUALITY_virtual=1
-DW_VIRTUALITY_pure_virtual=2
+DW_VIRTUALITY_none = 0
+DW_VIRTUALITY_virtual = 1
+DW_VIRTUALITY_pure_virtual = 2
# ID case
#
-DW_ID_case_sensitive=0
-DW_ID_up_case=1
-DW_ID_down_case=2
-DW_ID_case_insensitive=3
+DW_ID_case_sensitive = 0
+DW_ID_up_case = 1
+DW_ID_down_case = 2
+DW_ID_case_insensitive = 3
# Calling convention
#
-DW_CC_normal=0x1
-DW_CC_program=0x2
-DW_CC_nocall=0x3
+DW_CC_normal = 0x1
+DW_CC_program = 0x2
+DW_CC_nocall = 0x3
# Ordering
#
-DW_ORD_row_major=0
-DW_ORD_col_major=1
+DW_ORD_row_major = 0
+DW_ORD_col_major = 1
# Line program opcodes
@@ -136,3 +136,34 @@
DW_LNE_set_address = 0x02
DW_LNE_define_file = 0x03
+
+# Call frame instructions
+#
+DW_CFA_advance_loc = 0b01000000
+DW_CFA_offset = 0b10000000
+DW_CFA_restore = 0b11000000
+DW_CFA_nop = 0x00
+DW_CFA_set_loc = 0x01
+DW_CFA_advance_loc1 = 0x02
+DW_CFA_advance_loc2 = 0x03
+DW_CFA_advance_loc4 = 0x04
+DW_CFA_offset_extended = 0x05
+DW_CFA_restore_extended = 0x06
+DW_CFA_undefined = 0x07
+DW_CFA_same_value = 0x08
+DW_CFA_register = 0x09
+DW_CFA_remember_state = 0x0a
+DW_CFA_restore_state = 0x0b
+DW_CFA_def_cfa = 0x0c
+DW_CFA_def_cfa_register = 0x0d
+DW_CFA_def_cfa_offset = 0x0e
+DW_CFA_def_cfa_expression = 0x0f
+DW_CFA_expression = 0x10
+DW_CFA_offset_extended_sf = 0x11
+DW_CFA_def_cfa_sf = 0x12
+DW_CFA_def_cfa_offset_sf = 0x13
+DW_CFA_val_offset = 0x14
+DW_CFA_val_offset_sf = 0x15
+DW_CFA_val_expression = 0x16
+
+
diff --git a/elftools/dwarf/structs.py b/elftools/dwarf/structs.py
index d25178c..10154ae 100644
--- a/elftools/dwarf/structs.py
+++ b/elftools/dwarf/structs.py
@@ -126,6 +126,7 @@
self._create_abbrev_declaration()
self._create_dw_form()
self._create_lineprog_header()
+ self._create_callframe_entry_headers()
def _create_initial_length(self):
def _InitialLength(name):
