fixes #291 for incorrect syscall returns and some indent issues (#292)

* fixes #291 for incorrect syscall returns and some indent issues

* relative import fix

* commented weakref removal

manticore/platforms/linux.py

@@ -1,21 +1,22 @@
-import fcntl
-
-import cgcrandom
-import weakref
 import errno
-import os, struct
+import fcntl
+import logging
+import os
+import random
+import struct
+
+from elftools.elf.elffile import ELFFile
+
 from ..utils.helpers import issymbolic
 from ..core.cpu.abstractcpu import Interruption, Syscall, ConcretizeArgument
 from ..core.cpu.cpufactory import CpuFactory
 from ..core.memory import SMemory32, SMemory64, Memory32, Memory64
 from ..core.smtlib import Operators, ConstraintSet
 from ..platforms.platform import Platform
-from elftools.elf.elffile import ELFFile
-import logging
-import random
 from ..core.cpu.arm import *
 from ..core.executor import SyscallNotImplemented, ProcessExit
 from . import linux_syscalls
+
 logger = logging.getLogger("PLATFORM")
 
 
@@ -98,7 +99,6 @@ class SymbolicFile(object):
             path = File(path, mode)
         assert isinstance(path, File)
 
-        #self._constraints = weakref.ref(constraints)
         WILDCARD = '+'
 
         symbols_cnt = 0
@@ -622,7 +622,8 @@ class Linux(Platform):
         #The "secure execution" mode of secure_getenv() is controlled by the
         #AT_SECURE flag contained in the auxiliary vector passed from the
         #kernel to user space.
-        auxvnames = {'AT_IGNORE': 1, # Entry should be ignored 
+        auxvnames = {
+            'AT_IGNORE': 1, # Entry should be ignored
             'AT_EXECFD': 2, # File descriptor of program
             'AT_PHDR': 3, # Program headers for program
             'AT_PHENT':4, # Size of program header entry
@@ -998,11 +999,11 @@ class Linux(Platform):
          '''
         if not self._is_open(fd):
             logger.info("LSEEK: Not valid file descriptor on lseek. Returning EBADF")
-            return errno.EBADF
+            return -errno.EBADF
 
         if isinstance(self.files[fd], Socket):
             logger.info("LSEEK: Not valid file descriptor on lseek. Fd not seekable. Returning EBADF")
-            return errno.EBADF
+            return -errno.EBADF
 
         # Read the data and put in tin memory
         self.files[fd].seek(offset)
@@ -1016,12 +1017,12 @@ class Linux(Platform):
         if count != 0:
             if not self._is_open(fd):
                 logger.info("READ: Not valid file descriptor on read. Returning EBADF")
-                return errno.EBADF
+                return -errno.EBADF
 
             # TODO check count bytes from buf
             if not buf in self.current.memory: # or not  self.current.memory.isValid(buf+count):
                 logger.info("READ: buf points to invalid address. Returning EFAULT")
-                return errno.EFAULT
+                return -errno.EFAULT
 
             if isinstance(self.files[fd],Socket) and self.files[fd].is_empty():
                 return 0
@@ -2041,7 +2042,7 @@ class DecreeEmu(object):
 
     @staticmethod
     def cgc_random(platform, buf, count, rnd_bytes):
-        import cgcrandom
+        from . import cgcrandom
         if issymbolic(buf):
             logger.info("Ask to write random bytes to a symbolic buffer")
             raise ConcretizeArgument(0)