API: replace shift_offset by base_address

WARNING: base address is the negative of shift_offset

3 files changed, 27 insertions, 23 deletions

diff --git a/example/disasm/full.py b/example/disasm/full.py
index cc7f9be8..d159e8c6 100644
--- a/example/disasm/full.py
+++ b/example/disasm/full.py
@@ -45,9 +45,9 @@ parser.add_argument('-l', "--dontdis-retcall", action="store_true",
                     help="If set, disassemble only call destinations")
 parser.add_argument('-s', "--simplify", action="count",
                     help="Apply simplifications rules (liveness, graph simplification, ...)")
-parser.add_argument('-o', "--shiftoffset", default=0,
+parser.add_argument("--base-address", default=0,
                     type=lambda x: int(x, 0),
-                    help="Shift input binary by an offset")
+                    help="Base address of the input binary")
 parser.add_argument('-a', "--try-disasm-all", action="store_true",
                     help="Try to disassemble the whole binary")
 parser.add_argument('-i', "--image", action="store_true",
@@ -79,10 +79,10 @@ if args.verbose:
 log.info('Load binary')
 if args.rawbinary:
     cont = Container.fallback_container(open(args.filename, "rb").read(),
-                                        vm=None, addr=args.shiftoffset)
+                                        vm=None, addr=args.base_address)
 else:
     with open(args.filename, "rb") as fdesc:
-        cont = Container.from_stream(fdesc, addr=args.shiftoffset)
+        cont = Container.from_stream(fdesc, addr=args.base_address)
 
 default_addr = cont.entry_point
 bs = cont.bin_stream
diff --git a/miasm2/analysis/binary.py b/miasm2/analysis/binary.py
index 90d71369..93bd74b2 100644
--- a/miasm2/analysis/binary.py
+++ b/miasm2/analysis/binary.py
@@ -68,7 +68,7 @@ class Container(object):
         """Instantiate a container and parse the binary
         @stream: stream to use as binary
         @vm: (optional) VmMngr instance to link with the executable
-        @addr: (optional) Shift to apply before parsing the binary. If set,
+        @addr: (optional) Base address of the parsed binary. If set,
                force the unknown format
         """
         return Container.from_string(stream.read(), *args, **kwargs)
@@ -215,7 +215,7 @@ class ContainerUnknown(Container):
     "Container abstraction for unknown format"
 
     def parse(self, data, vm=None, addr=0, **kwargs):
-        self._bin_stream = bin_stream_str(data, shift=addr)
+        self._bin_stream = bin_stream_str(data, base_address=addr)
         if vm is not None:
             vm.add_memory_page(addr,
                                PAGE_READ,
diff --git a/miasm2/core/bin_stream.py b/miasm2/core/bin_stream.py
index 1dada90f..af31a52c 100644
--- a/miasm2/core/bin_stream.py
+++ b/miasm2/core/bin_stream.py
@@ -160,61 +160,65 @@ class bin_stream(object):
 
 class bin_stream_str(bin_stream):
 
-    def __init__(self, input_str="", offset=0L, shift=0):
+    def __init__(self, input_str="", offset=0L, base_address=0, shift=None):
         bin_stream.__init__(self)
+        if shift is not None:
+            raise DeprecationWarning("use base_address instead of shift")
         self.bin = input_str
         self.offset = offset
-        self.shift = shift
+        self.base_address = base_address
         self.l = len(input_str)
 
     def _getbytes(self, start, l=1):
-        if start + l + self.shift > self.l:
+        if start + l - self.base_address > self.l:
             raise IOError("not enough bytes in str")
-        if start + self.shift < 0:
+        if start - self.base_address < 0:
             raise IOError("Negative offset")
 
-        return super(bin_stream_str, self)._getbytes(start + self.shift, l)
+        return super(bin_stream_str, self)._getbytes(start - self.base_address, l)
 
     def readbs(self, l=1):
-        if self.offset + l + self.shift > self.l:
+        if self.offset + l - self.base_address > self.l:
             raise IOError("not enough bytes in str")
-        if self.offset + self.shift < 0:
+        if self.offset - self.base_address < 0:
             raise IOError("Negative offset")
         self.offset += l
-        return self.bin[self.offset - l + self.shift:self.offset + self.shift]
+        return self.bin[self.offset - l - self.base_address:self.offset - self.base_address]
 
     def __str__(self):
-        out = self.bin[self.offset + self.shift:]
+        out = self.bin[self.offset - self.base_address:]
         return out
 
     def setoffset(self, val):
         self.offset = val
 
     def getlen(self):
-        return self.l - (self.offset + self.shift)
+        return self.l - (self.offset - self.base_address)
 
 
 class bin_stream_file(bin_stream):
 
-    def __init__(self, binary, offset=0L, shift=0):
+    def __init__(self, binary, offset=0L, base_address=0, shift=None):
         bin_stream.__init__(self)
+        if shift is not None:
+            raise DeprecationWarning("use base_address instead of shift")
         self.bin = binary
         self.bin.seek(0, 2)
-        self.shift = shift
+        self.base_address = base_address
         self.l = self.bin.tell()
         self.offset = offset
 
     def getoffset(self):
-        return self.bin.tell() - self.shift
+        return self.bin.tell() + self.base_address
 
     def setoffset(self, val):
-        self.bin.seek(val + self.shift)
+        self.bin.seek(val - self.base_address)
     offset = property(getoffset, setoffset)
 
     def readbs(self, l=1):
-        if self.offset + l + self.shift > self.l:
+        if self.offset + l - self.base_address > self.l:
             raise IOError("not enough bytes in file")
-        if self.offset + self.shift < 0:
+        if self.offset - self.base_address < 0:
             raise IOError("Negative offset")
         return self.bin.read(l)
 
@@ -222,7 +226,7 @@ class bin_stream_file(bin_stream):
         return str(self.bin)
 
     def getlen(self):
-        return self.l - (self.offset + self.shift)
+        return self.l - (self.offset - self.base_address)
 
 
 class bin_stream_container(bin_stream):