v3: gstack-code-gen 生成

comparator/cobol_binary_reader.py

@@ -0,0 +1,43 @@
+import struct
+from pathlib import Path
+from data.field_tree import FieldTree
+
+
+class CobolBinaryReader:
+    def read(self, path: str, tree: FieldTree) -> list[dict]:
+        d = Path(path).read_bytes()
+        rs = self._record_size(tree)
+        if rs == 0 or len(d) == 0:
+            return []
+        return [self._parse(d[o:o + rs], tree) for o in range(0, len(d), rs) if len(d[o:o + rs]) >= rs]
+
+    def _record_size(self, tree):
+        return max((f.offset + f.length for f in tree.fields), default=0)
+
+    def _parse(self, r, tree):
+        out = {}
+        for n, f in tree.flatten().items():
+            if f.length == 0 or f.offset + f.length > len(r):
+                continue
+            raw = r[f.offset:f.offset + f.length]
+            if f.usage == "COMP-3":
+                out[n] = self._comp3(raw, f.signed, f.decimal)
+            elif f.usage in ("COMP", "COMP-5"):
+                out[n] = int.from_bytes(raw, "big", signed=f.signed)
+            else:
+                out[n] = raw.decode("ascii", errors="replace").strip()
+        return out
+
+    def _comp3(self, raw, signed, dec):
+        if not raw:
+            return "0"
+        nib = []
+        for b in raw:
+            nib.append((b >> 4) & 0xF)
+            nib.append(b & 0xF)
+        s = nib.pop()
+        v = sum(n * (10 ** (len(nib) - i)) for i, n in zip(range(len(nib)), nib))
+        if signed and s in (0xD, 0xB):
+            v = -v
+        d = 10 ** dec
+        return f"{float(v) / d:.{dec}f}" if dec else str(v)