#!/usr/bin/python
#
# Copyright 2006 Google Inc. All Rights Reserved.
"""Module for looking up symbolic debugging information.
The information can include symbol names, offsets, and source locations.
"""
import os
import re
import subprocess
ANDROID_BUILD_TOP = os.environ["ANDROID_BUILD_TOP"]
if not ANDROID_BUILD_TOP:
ANDROID_BUILD_TOP = "."
def FindSymbolsDir():
saveddir = os.getcwd()
os.chdir(ANDROID_BUILD_TOP)
try:
cmd = ("CALLED_FROM_SETUP=true BUILD_SYSTEM=build/core "
"SRC_TARGET_DIR=build/target make -f build/core/config.mk "
"dumpvar-abs-TARGET_OUT_UNSTRIPPED")
stream = subprocess.Popen(cmd, stdout=subprocess.PIPE, shell=True).stdout
return os.path.join(ANDROID_BUILD_TOP, stream.read().strip())
finally:
os.chdir(saveddir)
SYMBOLS_DIR = FindSymbolsDir()
def Uname():
"""'uname' for constructing prebuilt/<...> and out/host/<...> paths."""
uname = os.uname()[0]
if uname == "Darwin":
proc = os.uname()[-1]
if proc == "i386" or proc == "x86_64":
return "darwin-x86"
return "darwin-ppc"
if uname == "Linux":
return "linux-x86"
return uname
def ToolPath(tool, toolchain_info=None):
"""Return a full qualified path to the specified tool"""
if not toolchain_info:
toolchain_info = TOOLCHAIN_INFO
(label, target) = toolchain_info
return os.path.join(ANDROID_BUILD_TOP, "prebuilts", "gcc", Uname(), "arm", label, "bin",
target + "-" + tool)
def FindToolchain():
"""Look for the latest available toolchain
Args:
None
Returns:
A pair of strings containing toolchain label and target prefix.
"""
## Known toolchains, newer ones in the front.
known_toolchains = [
("arm-eabi-4.6", "arm-eabi"),
("arm-linux-androideabi-4.4.x", "arm-linux-androideabi"),
("arm-eabi-4.4.3", "arm-eabi"),
("arm-eabi-4.4.0", "arm-eabi"),
("arm-eabi-4.3.1", "arm-eabi"),
("arm-eabi-4.2.1", "arm-eabi")
]
# Look for addr2line to check for valid toolchain path.
for (label, target) in known_toolchains:
toolchain_info = (label, target);
if os.path.exists(ToolPath("addr2line", toolchain_info)):
return toolchain_info
raise Exception("Could not find tool chain")
TOOLCHAIN_INFO = FindToolchain()
def SymbolInformation(lib, addr):
"""Look up symbol information about an address.
Args:
lib: library (or executable) pathname containing symbols
addr: string hexidecimal address
Returns:
For a given library and address, return tuple of: (source_symbol,
source_location, object_symbol_with_offset) the values may be None
if the information was unavailable.
source_symbol may not be a prefix of object_symbol_with_offset if
the source function was inlined in the object code of another
function.
usually you want to display the object_symbol_with_offset and
source_location, the source_symbol is only useful to show if the
address was from an inlined function.
"""
info = SymbolInformationForSet(lib, set([addr]))
return (info and info.get(addr)) or (None, None, None)
def SymbolInformationForSet(lib, unique_addrs):
"""Look up symbol information for a set of addresses from the given library.
Args:
lib: library (or executable) pathname containing symbols
unique_addrs: set of hexidecimal addresses
Returns:
For a given library and set of addresses, returns a dictionary of the form
{addr: (source_symbol, source_location, object_symbol_with_offset)}. The
values may be None if the information was unavailable.
For a given address, source_symbol may not be a prefix of
object_symbol_with_offset if the source function was inlined in the
object code of another function.
Usually you want to display the object_symbol_with_offset and
source_location; the source_symbol is only useful to show if the
address was from an inlined function.
"""
if not lib:
return None
addr_to_line = CallAddr2LineForSet(lib, unique_addrs)
if not addr_to_line:
return None
addr_to_objdump = CallObjdumpForSet(lib, unique_addrs)
if not addr_to_objdump:
return None
result = {}
for addr in unique_addrs:
(source_symbol, source_location) = addr_to_line.get(addr, (None, None))
if addr in addr_to_objdump:
(object_symbol, object_offset) = addr_to_objdump.get(addr)
object_symbol_with_offset = FormatSymbolWithOffset(object_symbol,
object_offset)
else:
object_symbol_with_offset = None
result[addr] = (source_symbol, source_location, object_symbol_with_offset)
return result
def CallAddr2LineForSet(lib, unique_addrs):
"""Look up line and symbol information for a set of addresses.
Args:
lib: library (or executable) pathname containing symbols
unique_addrs: set of string hexidecimal addresses look up.
Returns:
A dictionary of the form {addr: (symbol, file:line)}. The values may
be (None, None) if the address could not be looked up.
"""
if not lib:
return None
symbols = SYMBOLS_DIR + lib
if not os.path.exists(symbols):
return None
(label, target) = TOOLCHAIN_INFO
cmd = [ToolPath("addr2line"), "--functions", "--demangle", "--exe=" + symbols]
child = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE)
result = {}
addrs = sorted(unique_addrs)
for addr in addrs:
child.stdin.write("0x%s\n" % addr)
child.stdin.flush()
symbol = child.stdout.readline().strip()
if symbol == "??":
symbol = None
location = child.stdout.readline().strip()
if location == "??:0":
location = None
result[addr] = (symbol, location)
child.stdin.close()
child.stdout.close()
return result
def CallObjdumpForSet(lib, unique_addrs):
"""Use objdump to find out the names of the containing functions.
Args:
lib: library (or executable) pathname containing symbols
unique_addrs: set of string hexidecimal addresses to find the functions for.
Returns:
A dictionary of the form {addr: (string symbol, offset)}.
"""
if not lib:
return None
symbols = SYMBOLS_DIR + lib
if not os.path.exists(symbols):
return None
symbols = SYMBOLS_DIR + lib
if not os.path.exists(symbols):
return None
addrs = sorted(unique_addrs)
start_addr_hex = addrs[0]
stop_addr_dec = str(int(addrs[-1], 16) + 8)
cmd = [ToolPath("objdump"),
"--section=.text",
"--demangle",
"--disassemble",
"--start-address=0x" + start_addr_hex,
"--stop-address=" + stop_addr_dec,
symbols]
# Function lines look like:
# 000177b0 <android::IBinder::~IBinder()+0x2c>:
# We pull out the address and function first. Then we check for an optional
# offset. This is tricky due to functions that look like "operator+(..)+0x2c"
func_regexp = re.compile("(^[a-f0-9]*) \<(.*)\>:$")
offset_regexp = re.compile("(.*)\+0x([a-f0-9]*)")
# A disassembly line looks like:
# 177b2: b510 push {r4, lr}
asm_regexp = re.compile("(^[ a-f0-9]*):[ a-f0-0]*.*$")
current_symbol = None # The current function symbol in the disassembly.
current_symbol_addr = 0 # The address of the current function.
addr_index = 0 # The address that we are currently looking for.
stream = subprocess.Popen(cmd, stdout=subprocess.PIPE).stdout
result = {}
for line in stream:
# Is it a function line like:
# 000177b0 <android::IBinder::~IBinder()>:
components = func_regexp.match(line)
if components:
# This is a new function, so record the current function and its address.
current_symbol_addr = int(components.group(1), 16)
current_symbol = components.group(2)
# Does it have an optional offset like: "foo(..)+0x2c"?
components = offset_regexp.match(current_symbol)
if components:
current_symbol = components.group(1)
offset = components.group(2)
if offset:
current_symbol_addr -= int(offset, 16)
# Is it an disassembly line like:
# 177b2: b510 push {r4, lr}
components = asm_regexp.match(line)
if components:
addr = components.group(1)
target_addr = addrs[addr_index]
i_addr = int(addr, 16)
i_target = int(target_addr, 16)
if i_addr == i_target:
result[target_addr] = (current_symbol, i_target - current_symbol_addr)
addr_index += 1
if addr_index >= len(addrs):
break
stream.close()
return result
def CallCppFilt(mangled_symbol):
cmd = [ToolPath("c++filt")]
process = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE)
process.stdin.write(mangled_symbol)
process.stdin.write("\n")
process.stdin.close()
demangled_symbol = process.stdout.readline().strip()
process.stdout.close()
return demangled_symbol
def FormatSymbolWithOffset(symbol, offset):
if offset == 0:
return symbol
return "%s+%d" % (symbol, offset)