ENH : extract latex characters

closes #2009

note: code clean up removed duplicates from adobe_glyphs

pypdf/_cmap.py

@@ -200,12 +200,15 @@ def parse_to_unicode(
  int_entry: List[int] = []
 
  if "/ToUnicode" not in ft:
- return {}, space_code, []
+ if ft.get("/Subtype", "") == "/Type1":
+ return type1_alternative(ft, map_dict, space_code, int_entry)
+ else:
+ return {}, space_code, []
  process_rg: bool = False
  process_char: bool = False
  multiline_rg: Union[
  None, Tuple[int, int]
- ] = None # tuple = (current_char, remaining size) ; cf #1285 for example of file
+ ] = None # tuple = (current_chaxr, remaining size) ; cf #1285 for example of file
  cm = prepare_cm(ft)
  for line in cm.split(b"\n"):
  process_rg, process_char, multiline_rg = process_cm_line(
@@ -434,3 +437,35 @@ def compute_space_width(
  cpt += 1
  sp_width = m / max(1, cpt) / 2
  return sp_width
+
+
+def type1_alternative(
+ ft: DictionaryObject,
+ map_dict: Dict[Any, Any],
+ space_code: int,
+ int_entry: List[int],
+) -> Tuple[Dict[Any, Any], int, List[int]]:
+ if "/FontDescriptor" not in ft:
+ return map_dict, space_code, int_entry
+ ft_desc = cast(DictionaryObject, ft["/FontDescriptor"]).get("/FontFile")
+ if ft_desc is None:
+ return map_dict, space_code, int_entry
+ txt = ft_desc.get_object().get_data()
+ txt = txt.split(b"eexec\n")[0] # only clear part
+ txt = txt.split(b"/Encoding")[1] # to get the encoding part
+ lines = txt.replace(b"\r", b"\n").split(b"\n")
+ for li in lines:
+ if li.startswith(b"dup"):
+ words = [_w for _w in li.split(b" ") if _w != b""]
+ if words[3] != b"put":
+ continue
+ try:
+ i = int(words[1])
+ v = adobe_glyphs[words[2].decode()]
+ except (ValueError, KeyError):
+ continue
+ if v == " ":
+ space_code = i
+ map_dict[chr(i)] = v
+ int_entry.append(i)
+ return map_dict, space_code, int_entry