fix(emulate): let `emulate` works on unicorn-1.0.2rc1 ~ unicorn-1.0.2

pwndbg/disasm/__init__.py

@@ -214,16 +214,14 @@ def near(address, instructions=1, emulate=False, show_prev_insns=True):
     if address == pc and emulate:
         emu = pwndbg.emu.emulator.Emulator()
 
-        # For whatever reason, the first instruction is emulated twice.
-        # Skip the first one here.
-        emu.single_step()
-
     # Now find all of the instructions moving forward.
     #
     # At this point, we've already added everything *BEFORE* the requested address,
     # and the instruction at 'address'.
     insn = current
     total_instructions = 1 + (2*instructions)
+    last_emu_target = None
+    target_candidate = address
 
     while insn and len(insns) < total_instructions:
         target = insn.target
@@ -236,7 +234,14 @@ def near(address, instructions=1, emulate=False, show_prev_insns=True):
         # If we initialized the emulator and emulation is still enabled, we can use it
         # to figure out the next instruction.
         if emu:
-            target_candidate, size_candidate = emu.single_step()
+            # For whatever reason, the first instruction is emulated twice on
+            # unicorn-1.0.2rc1~unicorn-1.0.2rc3, but not on >= unicorn-1.0.2rc4.
+            # If the address is equal with the last one, skip it
+            last_emu_target = target_candidate
+            while last_emu_target == target_candidate:
+                target_candidate, size_candidate = emu.single_step()
+                if not target_candidate:
+                    break
 
             if None not in (target_candidate, size_candidate):
                 target = target_candidate