fix!: Partially reimplement StringsBlock

.gitignore

@@ -13,4 +13,5 @@ hl/
 *.json
 build*.bat
 pypi_token.txt
-testenv
+testenv
+.crashlink_debug

crashlink/core.py

@@ -394,50 +394,48 @@ def __init__(self) -> None:
         self.length.length = 4
         self.value: List[str] = []
         self.lengths: List[int] = []
-        self.embedded_lengths: List[VarInt] = []
+        self.lengths: List[VarInt] = []
 
-    def deserialise(self, f: BinaryIO | BytesIO) -> "StringsBlock":
+    def deserialise(self, f: BinaryIO | BytesIO, nstrings: int) -> "StringsBlock":
         self.length.deserialise(f, length=4)
-        strings_size = self.length.value
-        dbg_print(f"Found {fmt_bytes(strings_size)} of strings")
-        strings_data: bytes = f.read(strings_size)
-
-        index = 0
-        while index < strings_size:
-            string_length = 0
-            while index + string_length < strings_size and strings_data[index + string_length] != 0:
-                string_length += 1
-
-            if index + string_length >= strings_size:
-                raise MalformedBytecode("Invalid string: no null terminator found")
-
-            string = strings_data[index : index + string_length].decode("utf-8", errors="surrogateescape")
-            self.value.append(string)
-            self.lengths.append(string_length)
-
-            index += string_length + 1  # Skip the null terminator
-
-        for _ in self.value:
-            self.embedded_lengths.append(VarInt().deserialise(f))
-
-        return self
+        size = self.length.value
+        sdata: bytes = f.read(size)
+        strings: List[str] = []
+        lengths: List[VarInt] = []
+        curpos = 0
+        for _ in range(nstrings):
+            sz = VarInt().deserialise(f)
+            if curpos + sz.value >= size:
+                raise ValueError("Invalid string")
+
+            str_value = sdata[curpos:curpos + sz.value]
+            if curpos + sz.value < size and sdata[curpos + sz.value] != 0:
+                raise ValueError("Invalid string")
+
+            strings.append(str_value.decode('utf-8', errors="surrogateescape"))
+            lengths.append(sz)
+
+            curpos += sz.value + 1  # +1 for null terminator
+        self.value = strings
+        self.lengths = lengths
 
     def serialise(self) -> bytes:
         strings_data = b""
         for string in self.value:
             strings_data += string.encode("utf-8", errors="surrogateescape") + b"\x00"
         self.length.value = len(strings_data)
-        self.lengths = [len(string) for string in self.value]
-        self.embedded_lengths = [VarInt(length) for length in self.lengths]
+        self.lengths = [VarInt(len(string)) for string in self.value]
         return b"".join(
             [
                 self.length.serialise(),
                 strings_data,
-                b"".join([i.serialise() for i in self.embedded_lengths]),
+                b"".join([i.serialise() for i in self.lengths]),
             ]
         )
 
 
+
+
 class BytesBlock(Serialisable):
     """
     Block of bytes in the bytecode. Contains a list of byte strings and their lengths.
@@ -1425,7 +1423,7 @@ def deserialise(self, f: BinaryIO | BytesIO, search_magic: bool = True) -> "Byte
 
         dbg_print(f"Strings section starts at {tell(f)}")
         self.track_section(f, "strings")
-        self.strings.deserialise(f)
+        self.strings.deserialise(f, self.nstrings.value)
         dbg_print(f"Strings section ends at {tell(f)}")
         assert self.nstrings.value == len(self.strings.value), "nstrings and len of strings don't match!"
 
@@ -1442,7 +1440,7 @@ def deserialise(self, f: BinaryIO | BytesIO, search_magic: bool = True) -> "Byte
             self.ndebugfiles.deserialise(f)
             dbg_print(f"Number of debug files: {self.ndebugfiles.value}")
             self.track_section(f, "debugfiles")
-            self.debugfiles.deserialise(f)
+            self.debugfiles.deserialise(f, self.ndebugfiles.value)
         else:
             self.ndebugfiles = None
             self.debugfiles = None
@@ -1546,7 +1544,10 @@ def const_str(self, gindex: int) -> str:
         obj_fields = obj.resolve_fields(self)
         if len(obj_fields) != 2:
             raise ValueError(f"Global {gindex} seems malformed!")
-        return self.initialized_globals[gindex][obj_fields[0].name.resolve(self)]
+        res = self.initialized_globals[gindex][obj_fields[0].name.resolve(self)]
+        if not isinstance(res, str):
+            raise TypeError(f"This should never happen!")
+        return res
 
     def serialise(self, auto_set_meta: bool = True) -> bytes:
         start_time = datetime.now()

crashlink/decomp.py

@@ -279,14 +279,14 @@ def graph(self, code: Bytecode) -> str:
         dot.append("}")
         return "\n".join(dot)
 
-    def num_incoming(self, node: CFNode) -> int:
-        count = 0
+    def predecessors(self, node: CFNode) -> List[CFNode]:
+        """Get predecessors of a node"""
+        preds = []
         for n in self.nodes:
-            for branch, _ in n.branches:
-                if branch == node:
-                    count += 1
-        return count
-
+            for succ, _ in n.branches:
+                if succ == node:
+                    preds.append(n)
+        return preds
 
 class IRStatement(ABC):
     def __init__(self, code: Bytecode):
@@ -605,6 +605,28 @@ def __repr__(self) -> str:
         return f"<IRConditional: if {self.condition} then\n{self.true_block}\nelse\n{self.false_block}>"
 
 
+class IRLoop(IRStatement):
+    """Loop statement"""
+
+    def __init__(self, code: Bytecode, condition: IRExpression, body: IRBlock):
+        super().__init__(code)
+        self.condition = condition
+        self.body = body
+
+    def __repr__(self) -> str:
+        return f"<IRLoop: while {self.condition}\n{self.body}>"
+
+
+class IRBreak(IRStatement):
+    """Break statement"""
+
+    def __init__(self, code: Bytecode):
+        super().__init__(code)
+
+    def __repr__(self) -> str:
+        return "<IRBreak>"
+
+
 class IRReturn(IRStatement):
     """Return statement"""
 
@@ -722,13 +744,15 @@ def _find_convergence(self, true_node: CFNode, false_node: CFNode, visited: Set[
 
         return None  # No convergence found
 
-    def _lift_block(self, node: CFNode, visited: Optional[Set[CFNode]] = None) -> IRBlock:
-        """Lift a control flow node to an IR block"""
+    def _lift_block(self, node: CFNode, 
+                    visited: Optional[Set[CFNode]] = None) -> IRBlock:
         if visited is None:
             visited = set()
+
+        if node in visited:                
+            return IRBlock(self.code)
 
-        if node in visited:
-            return IRBlock(self.code)  # Return empty block for cycles
+        visited.add(node)
 
         visited.add(node)
         block = IRBlock(self.code)
@@ -799,13 +823,13 @@ def _lift_block(self, node: CFNode, visited: Optional[Set[CFNode]] = None) -> IR
                 # it's an empty block and that's what comes *after* the conditional branches altogether.
                 should_lift_t = True
                 should_lift_f = True
-                if self.cfg.num_incoming(true_branch) > 1:
+                if len(self.cfg.predecessors(true_branch)) > 1:
                     should_lift_t = False
-                if self.cfg.num_incoming(false_branch) > 1:
+                if len(self.cfg.predecessors(false_branch)) > 1:
                     should_lift_f = False
 
                 if not should_lift_t and not should_lift_f:
-                    print("WARNING: Skipping conditional due to weird incoming branches.")
+                    dbg_print("Warning: Skipping conditional due to weird incoming branches.")
                     continue
 
                 cond_map = {

crashlink/globals.py

@@ -4,6 +4,13 @@
 
 from io import BytesIO
 from typing import Any, BinaryIO
+import os
+
+def _is_debug() -> bool:
+    """
+    Determine whether or not to enable debug mode. 
+    """
+    return bool(os.getenv("CRASHLINK_DEBUG", False)) or bool(os.getenv("DEBUG", False)) or os.path.exists(".crashlink_debug")
 
 VERSION: str = "v0.0.1a"
 """
@@ -15,7 +22,7 @@
 String displayed in the help message for the CLI.
 """
 
-DEBUG: bool = False
+DEBUG: bool = False or _is_debug()
 """
 Whether to enable certain features meant only for development or debugging of crashlink.
 """