Merge pull request #912 from elicn/os-loader-improv

Minor improvements to QlOs and QlLoader

Author: xwings

qiling/loader/loader.py

@@ -9,7 +9,7 @@
 
 Image = NamedTuple('Image', (('base', int), ('end', int), ('path', str)))
 
-class QlLoader():
+class QlLoader:
     def __init__(self, ql: Qiling):
         self.ql = ql
         self.env = self.ql.env
@@ -26,3 +26,7 @@ def save(self) -> Mapping[str, Any]:
 
     def restore(self, saved_state: Mapping[str, Any]):
         self.images = [Image(*img) for img in saved_state['images']]
+
+    # loader main method; derivatives must implement one of their own
+    def run(self) -> None:
+        raise NotImplementedError

qiling/os/os.py

@@ -6,6 +6,8 @@
 import sys
 from typing import Any, Iterable, Optional, Callable, Mapping, Sequence, TextIO, Tuple
 
+from unicorn import UcError
+
 from qiling import Qiling
 from qiling.const import QL_OS, QL_INTERCEPT, QL_OS_POSIX
 from qiling.os.const import STRING, WSTRING, GUID
@@ -202,36 +204,39 @@ def find_containing_image(self, pc):
             if image.base <= pc < image.end:
                 return image
 
+    # os main method; derivatives must implement one of their own
+    def run(self) -> None:
+        raise NotImplementedError
+
     def stop(self):
         if self.ql.multithread:
             self.thread_management.stop() 
         else:
             self.ql.emu_stop()
 
     def emu_error(self):
-        self.ql.log.error("\n")
-
+        self.ql.log.error(f'CPU Context:')
         for reg in self.ql.reg.register_mapping:
             if isinstance(reg, str):
-                REG_NAME = reg
-                REG_VAL = self.ql.reg.read(reg)
-                self.ql.log.error("%s\t:\t 0x%x" % (REG_NAME, REG_VAL))
-
-        self.ql.log.error("\n")
-        self.ql.log.error("PC = 0x%x" % (self.ql.reg.arch_pc))
-        containing_image = self.find_containing_image(self.ql.reg.arch_pc)
-        if containing_image:
-            offset = self.ql.reg.arch_pc - containing_image.base
-            self.ql.log.error(" (%s+0x%x)" % (containing_image.path, offset))
-        else:
-            self.ql.log.info("\n")
-        self.ql.mem.show_mapinfo()
+                self.ql.log.error(f'{reg}\t: {self.ql.reg.read(reg):#x}')
+
+        pc = self.ql.reg.arch_pc
 
         try:
-            buf = self.ql.mem.read(self.ql.reg.arch_pc, 8)
-            self.ql.log.error("%r" % ([hex(_) for _ in buf]))
+            data = self.ql.mem.read(pc, size=8)
+        except UcError:
+            pc_info = ' (unreachable)'
+        else:
+            self.ql.log.error('Hexdump:')
+            self.ql.log.error(data.hex(' '))
+
+            self.ql.log.error('Disassembly:')
+            self.ql.arch.utils.disassembler(self.ql, pc, 64)
+
+            containing_image = self.find_containing_image(pc)
+            pc_info = f' ({containing_image.path} + {pc - containing_image.base:#x})' if containing_image else ''
+        finally:
+            self.ql.log.error(f'PC = {pc:#0{self.ql.pointersize * 2 + 2}x}{pc_info}\n')
 
-            self.ql.log.info("\n")
-            self.utils.disassembler(self.ql, self.ql.reg.arch_pc, 64)
-        except:
-            self.ql.log.error("Error: PC(0x%x) Unreachable" % self.ql.reg.arch_pc)
+            self.ql.log.info(f'Memory map:')
+            self.ql.mem.show_mapinfo()