HashedFile: Raise FileDoesNotExist if referring to a non-existing file

A custom exception is nicer to handle in the caller.

daklib/checks.py

@@ -31,7 +31,7 @@ from daklib.regexes import *
 from daklib.textutils import fix_maintainer, ParseMaintError
 import daklib.lintian as lintian
 import daklib.utils as utils
-from daklib.upload import InvalidHashException
+import daklib.upload
 
 import apt_inst
 import apt_pkg
@@ -160,13 +160,11 @@ class SignatureAndHashesCheck(Check):
         try:
             for f in files:
                 f.check(upload.directory)
-        except IOError as e:
-            if e.errno == errno.ENOENT:
-                raise Reject('{0} refers to non-existing file: {1}\n'
-                             'Perhaps you need to include it in your upload?'
-                             .format(filename, os.path.basename(e.filename)))
-            raise
-        except InvalidHashException as e:
+        except daklib.upload.FileDoesNotExist as e:
+            raise Reject('{0}: {1}\n'
+                         'Perhaps you need to include the file in your upload?'
+                         .format(filename, unicode(e)))
+        except daklib.upload.UploadException as e:
             raise Reject('{0}: {1}'.format(filename, unicode(e)))
 
 class ChangesCheck(Check):

daklib/upload.py

@@ -63,6 +63,12 @@ class InvalidFilenameException(UploadException):
     def __str__(self):
         return "Invalid filename '{0}'.".format(self.filename)
 
+class FileDoesNotExist(UploadException):
+    def __init__(self, filename):
+        self.filename = filename
+    def __str__(self):
+        return "Refers to non-existing file '{0}'".format(self.filename)
+
 class HashedFile(object):
     """file with checksums
     """
@@ -124,8 +130,8 @@ class HashedFile(object):
         @return: C{HashedFile} object for the given file
         """
         path = os.path.join(directory, filename)
-        size = os.stat(path).st_size
         with open(path, 'r') as fh:
+            size = os.fstat(fh.fileno()).st_size
             hashes = apt_pkg.Hashes(fh)
         return cls(filename, size, hashes.md5, hashes.sha1, hashes.sha256, section, priority)
 
@@ -141,13 +147,18 @@ class HashedFile(object):
         """
         path = os.path.join(directory, self.filename)
 
-        size = os.stat(path).st_size
+        try:
+            with open(path) as fh:
+                size = os.fstat(fh.fileno()).st_size
+                hashes = apt_pkg.Hashes(fh)
+        except IOError as e:
+            if e.errno == errno.ENOENT:
+                raise FileDoesNotExist(self.filename)
+            raise
+
         if size != self.size:
             raise InvalidHashException(self.filename, 'size', self.size, size)
 
-        with open(path) as fh:
-            hashes = apt_pkg.Hashes(fh)
-
         if hashes.md5 != self.md5sum:
             raise InvalidHashException(self.filename, 'md5sum', self.md5sum, hashes.md5)