debugger.py

   1
   2 # This is a wrapper for sel_ldr that annotates the backtrace it
   3 # outputs with source code info.
   4
   5 import re
   6 import subprocess
   7 import sys
   8
   9
  10 def addr2line(obj_file, addr, indent=""):
  11     proc = subprocess.Popen(["addr2line", "-f", "-e", obj_file, "%x" % addr],
  12                             stdout=subprocess.PIPE)
  13     for line in proc.stdout:
  14         print indent + line,
  15     assert proc.wait() == 0
  16
  17
  18 def main(argv):
  19     executable = argv[0]
  20     maps = [{"base": 0x20000, "offset": 0x20000, "size": 0x2d000,
  21              "path": "install-stubout/lib/ld-linux.so.2", "file": "ld.so"}]
  22     # TODO: don't assume executable's load address and size
  23     maps.append({"base": 0x1000000, "offset": 0, "size": 0x10000,
  24                  "path": executable, "file": executable})
  25
  26     def match():
  27         last_path = "?"
  28         last_file = "?"
  29         while True:
  30             line = yield
  31             m = re.search("trying file=(.*)", line)
  32             if m is not None:
  33                 last_path = m.group(1)
  34
  35             m = re.search("file=(\S+).*generating link map", line)
  36             if m is not None:
  37                 last_file = m.group(1)
  38
  39             m = re.search("base: (\S+)\s+size: (\S+)", line)
  40             if m is not None:
  41                 # base value assumes this is an ET_DYN object.
  42                 info = {"base": int(m.group(1), 0),
  43                         "offset": int(m.group(1), 0),
  44                         "size": int(m.group(2), 0),
  45                         "path": last_path,
  46                         "file": last_file}
  47                 maps.append(info)
  48
  49     args = ["sel_ldr",
  50             "-E", "LD_DEBUG=all",
  51             "-d",
  52             "install-stubout/lib/ld-linux.so.2",
  53             "--", "--library-path", "install-stubout/lib",
  54             ] + argv
  55     proc = subprocess.Popen(
  56         args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
  57     matcher = match()
  58     matcher.send(None)
  59
  60     def decode_addr(addr):
  61         for obj in maps:
  62             if obj["base"] <= addr < obj["base"] + obj["size"]:
  63                 offset = addr - obj["offset"]
  64                 print "    in %s: offset=%x" % (obj["path"], offset)
  65                 addr2line(obj["path"], offset, "    ")
  66
  67     for line in proc.stdout:
  68         print line,
  69         matcher.send(line)
  70         m = re.search("code_addr=(\S+)", line)
  71         if m is not None:
  72             decode_addr(int(m.group(1), 16))
  73
  74     print "exit status:", proc.wait()
  75     print "libraries loaded:"
  76     fmt = "  %(base)08x-%(end)08x size=%(size)08x file=%(file)s path=%(path)s"
  77     for obj in sorted(maps, key=lambda obj: obj["base"]):
  78         obj["end"] = obj["base"] + obj["size"]
  79         print fmt % obj
  80
  81
  82 if __name__ == "__main__":
  83     main(sys.argv[1:])