lib/oe/qa.py

   1 class ELFFile:
   2     EI_NIDENT = 16
   3
   4     EI_CLASS      = 4
   5     EI_DATA       = 5
   6     EI_VERSION    = 6
   7     EI_OSABI      = 7
   8     EI_ABIVERSION = 8
   9
  10     # possible values for EI_CLASS
  11     ELFCLASSNONE = 0
  12     ELFCLASS32   = 1
  13     ELFCLASS64   = 2
  14
  15     # possible value for EI_VERSION
  16     EV_CURRENT   = 1
  17
  18     # possible values for EI_DATA
  19     ELFDATANONE  = 0
  20     ELFDATA2LSB  = 1
  21     ELFDATA2MSB  = 2
  22
  23     def my_assert(self, expectation, result):
  24         if not expectation == result:
  25             #print "'%x','%x' %s" % (ord(expectation), ord(result), self.name)
  26             raise Exception("This does not work as expected")
  27
  28     def __init__(self, name, bits32):
  29         self.name = name
  30         self.bits32 = bits32
  31
  32     def open(self):
  33         self.file = file(self.name, "r")
  34         self.data = self.file.read(ELFFile.EI_NIDENT+4)
  35
  36         self.my_assert(len(self.data), ELFFile.EI_NIDENT+4)
  37         self.my_assert(self.data[0], chr(0x7f) )
  38         self.my_assert(self.data[1], 'E')
  39         self.my_assert(self.data[2], 'L')
  40         self.my_assert(self.data[3], 'F')
  41         if self.bits32 :
  42             self.my_assert(self.data[ELFFile.EI_CLASS], chr(ELFFile.ELFCLASS32))
  43         else:
  44             self.my_assert(self.data[ELFFile.EI_CLASS], chr(ELFFile.ELFCLASS64))
  45         self.my_assert(self.data[ELFFile.EI_VERSION], chr(ELFFile.EV_CURRENT) )
  46
  47         self.sex = self.data[ELFFile.EI_DATA]
  48         if self.sex == chr(ELFFile.ELFDATANONE):
  49             raise Exception("self.sex == ELFDATANONE")
  50         elif self.sex == chr(ELFFile.ELFDATA2LSB):
  51             self.sex = "<"
  52         elif self.sex == chr(ELFFile.ELFDATA2MSB):
  53             self.sex = ">"
  54         else:
  55             raise Exception("Unknown self.sex")
  56
  57     def osAbi(self):
  58         return ord(self.data[ELFFile.EI_OSABI])
  59
  60     def abiVersion(self):
  61         return ord(self.data[ELFFile.EI_ABIVERSION])
  62
  63     def isLittleEndian(self):
  64         return self.sex == "<"
  65
  66     def isBigEngian(self):
  67         return self.sex == ">"
  68
  69     def machine(self):
  70         """
  71         We know the sex stored in self.sex and we
  72         know the position
  73         """
  74         import struct
  75         (a,) = struct.unpack(self.sex+"H", self.data[18:20])
  76         return a