Merge pull request #7382 from nopperl/parse-eps-trailer

Read bounding box information from the trailer of EPS files if specified

Tests/test_file_eps.py

@@ -404,3 +404,18 @@ def test_timeout(test_file):
         with pytest.raises(Image.UnidentifiedImageError):
             with Image.open(f):
                 pass
+
+
+def test_bounding_box_in_trailer():
+    # Check bounding boxes are parsed in the same way
+    # when specified in the header and the trailer
+    with Image.open("Tests/images/zero_bb_trailer.eps") as trailer_image, Image.open(
+        FILE1
+    ) as header_image:
+        assert trailer_image.size == header_image.size
+
+
+def test_eof_before_bounding_box():
+    with pytest.raises(OSError):
+        with Image.open("Tests/images/zero_bb_eof_before_boundingbox.eps"):
+            pass

src/PIL/EpsImagePlugin.py

@@ -233,7 +233,9 @@ class EpsImageFile(ImageFile.ImageFile):
         byte_arr = bytearray(255)
         bytes_mv = memoryview(byte_arr)
         bytes_read = 0
-        reading_comments = True
+        reading_header_comments = True
+        reading_trailer_comments = False
+        trailer_reached = False
 
         def check_required_header_comments():
             if "PS-Adobe" not in self.info:
@@ -243,6 +245,36 @@ class EpsImageFile(ImageFile.ImageFile):
                 msg = 'EPS header missing "%%BoundingBox" comment'
                 raise SyntaxError(msg)
 
+        def _read_comment(s):
+            nonlocal reading_trailer_comments
+            try:
+                m = split.match(s)
+            except re.error as e:
+                msg = "not an EPS file"
+                raise SyntaxError(msg) from e
+
+            if m:
+                k, v = m.group(1, 2)
+                self.info[k] = v
+                if k == "BoundingBox":
+                    if v == "(atend)":
+                        reading_trailer_comments = True
+                    elif not self._size or (
+                        trailer_reached and reading_trailer_comments
+                    ):
+                        try:
+                            # Note: The DSC spec says that BoundingBox
+                            # fields should be integers, but some drivers
+                            # put floating point values there anyway.
+                            box = [int(float(i)) for i in v.split()]
+                            self._size = box[2] - box[0], box[3] - box[1]
+                            self.tile = [
+                                ("eps", (0, 0) + self.size, offset, (length, box))
+                            ]
+                        except Exception:
+                            pass
+                return True
+
         while True:
             byte = self.fp.read(1)
             if byte == b"":
@@ -265,9 +297,9 @@ class EpsImageFile(ImageFile.ImageFile):
                         msg = "not an EPS file"
                         raise SyntaxError(msg)
                     else:
-                        if reading_comments:
+                        if reading_header_comments:
                             check_required_header_comments()
-                            reading_comments = False
+                            reading_header_comments = False
                         # reset bytes_read so we can keep reading
                         # data until the end of the line
                         bytes_read = 0
@@ -275,7 +307,7 @@ class EpsImageFile(ImageFile.ImageFile):
                 bytes_read += 1
                 continue
 
-            if reading_comments:
+            if reading_header_comments:
                 # Load EPS header
 
                 # if this line doesn't start with a "%",
@@ -283,33 +315,11 @@ class EpsImageFile(ImageFile.ImageFile):
                 # then we've reached the end of the header/comments
                 if byte_arr[0] != ord("%") or bytes_mv[:13] == b"%%EndComments":
                     check_required_header_comments()
-                    reading_comments = False
+                    reading_header_comments = False
                     continue
 
                 s = str(bytes_mv[:bytes_read], "latin-1")
-
-                try:
-                    m = split.match(s)
-                except re.error as e:
-                    msg = "not an EPS file"
-                    raise SyntaxError(msg) from e
-
-                if m:
-                    k, v = m.group(1, 2)
-                    self.info[k] = v
-                    if k == "BoundingBox":
-                        try:
-                            # Note: The DSC spec says that BoundingBox
-                            # fields should be integers, but some drivers
-                            # put floating point values there anyway.
-                            box = [int(float(i)) for i in v.split()]
-                            self._size = box[2] - box[0], box[3] - box[1]
-                            self.tile = [
-                                ("eps", (0, 0) + self.size, offset, (length, box))
-                            ]
-                        except Exception:
-                            pass
-                else:
+                if not _read_comment(s):
                     m = field.match(s)
                     if m:
                         k = m.group(1)
@@ -355,7 +365,18 @@ class EpsImageFile(ImageFile.ImageFile):
 
                 self._size = columns, rows
                 return
+            elif trailer_reached and reading_trailer_comments:
+                # Load EPS trailer
 
+                # if this line starts with "%%EOF",
+                # then we've reached the end of the file
+                if bytes_mv[:5] == b"%%EOF":
+                    break
+
+                s = str(bytes_mv[:bytes_read], "latin-1")
+                _read_comment(s)
+            elif bytes_mv[:9] == b"%%Trailer":
+                trailer_reached = True
             bytes_read = 0
 
         check_required_header_comments()