1 files changed, 58 insertions, 0 deletions
diff --git a/vdrnfofs/concatenated_file_reader.py b/vdrnfofs/concatenated_file_reader.py
new file mode 100644
index 0000000..9f05ebd
--- /dev/null
+++ b/vdrnfofs/concatenated_file_reader.py
@@ -0,0 +1,58 @@
+# -*- coding: utf-8 -*-
+#
+# VDR-NFO-FS creates a file system for VDR recordings, which maps each
+# recording to a single mpg-file and nfo-file containing some meta data.
+#
+# Copyright (C) 2010 - 2011 by Tobias Grimm
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+import os
+
+class ConcatenatedFileReader:
+    def __init__(self, filenames):
+        self.files = [(f, os.path.getsize(f)) for f in filenames]
+        self.current_filename = None
+        self.current_file = None
+
+    def read(self, offset, size):
+        buffer = ""
+        ptr = offset
+        while (len(buffer) < size):
+            (filename, file_offset) = self.filename_from_offset(ptr)
+            if filename:
+                if (self.current_filename != filename):
+                    if self.current_file:
+                        self.current_file.close()
+                    self.current_filename = filename
+                    self.current_file = open(filename, 'r')
+                self.current_file.seek(file_offset)
+                buffer += self.current_file.read(size - len(buffer))
+                ptr = offset + len(buffer)
+            else:
+                break
+        return buffer
+
+    def release(self):
+        if self.current_file:
+            self.current_file.close()
+
+    def filename_from_offset(self, offset):
+        for (filename, size) in self.files:
+            if offset >= size:
+                offset -= size
+            else:
+                return (filename, offset)
+        return (None, 0)