merge hash generation for Release files

_get_file_sum() in mini-dinstall and _get_file_md5sum() in ChangeFile.py
are really the same code. So I strip it together into get_file_sum() in
misc.py.

2 files changed, 61 insertions, 35 deletions

diff --git a/minidinstall/ChangeFile.py b/minidinstall/ChangeFile.py
index b74e623..969ae09 100644
--- a/minidinstall/ChangeFile.py
+++ b/minidinstall/ChangeFile.py
@@ -18,10 +18,11 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-import os, re, sys, string, stat, popen2
+import os, re, sys, string, stat
 import threading, Queue
 import logging
 from minidinstall import DpkgControl, SignedFile
+from minidinstall import misc
 
 class ChangeFileException(Exception):
     def __init__(self, value):
@@ -70,40 +71,8 @@ class ChangeFile(DpkgControl.DpkgParagraph):
             raise ChangeFileException("Can't stat %s: %s" % (filename,e.strerror))
         if size != expected_size:
             raise ChangeFileException("File size for %s does not match that specified in .dsc" % (filename,))
-        if (self._get_file_md5sum(filename) != expected_md5sum):
+        if (misc.get_file_sum(self, 'md5', filename) != expected_md5sum):
             raise ChangeFileException("md5sum for %s does not match that specified in .dsc" % (filename,))
         self._logger.debug('Verified md5sum %s and size %s for %s' % (expected_md5sum, expected_size, filename))
 
-    def _get_file_md5sum(self, filename):
-        if os.access('/usr/bin/md5sum', os.X_OK):
-            cmd = '/usr/bin/md5sum %s' % (filename,)
-            self._logger.debug("Running: %s" % (cmd,))
-            child = popen2.Popen3(cmd, 1)
-            child.tochild.close()
-            erroutput = child.childerr.read()
-            child.childerr.close()
-            if erroutput != '':
-                child.fromchild.close()
-                raise ChangeFileException("md5sum returned error output \"%s\"" % (erroutput,))
-            (md5sum, filename) = string.split(child.fromchild.read(), None, 1)
-            child.fromchild.close()
-            status = child.wait()
-            if not (status is None or (os.WIFEXITED(status) and os.WEXITSTATUS(status) == 0)):
-                if os.WIFEXITED(status):
-                    msg = "md5sum exited with error code %d" % (os.WEXITSTATUS(status),)
-                elif os.WIFSTOPPED(status):
-                    msg = "md5sum stopped unexpectedly with signal %d" % (os.WSTOPSIG(status),)
-                elif os.WIFSIGNALED(status):
-                    msg = "md5sum died with signal %d" % (os.WTERMSIG(status),)
-                raise ChangeFileException(msg)
-            return md5sum.strip()
-        import md5
-        f = open(filename)
-        md5sum = md5.new()
-        buf = f.read(8192)
-        while buf != '':
-            md5sum.update(buf)
-            buf = f.read(8192)
-        return md5sum.hexdigest()
-
 # vim:ts=4:sw=4:et:
diff --git a/minidinstall/misc.py b/minidinstall/misc.py
index e88f5a9..a3c9489 100644
--- a/minidinstall/misc.py
+++ b/minidinstall/misc.py
@@ -18,7 +18,7 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
-import os, errno, time, string, re
+import os, errno, time, string, re, popen2
 
 def dup2(fd,fd2):
   # dup2 with EBUSY retries (cf. dup2(2) and Debian bug #265513)
@@ -45,3 +45,60 @@ def format_changes(L):
         L1.append(dotmatch.sub('', x))
 
     return "\n".join(L1)
+
+def get_file_sum(self, type, filename):
+    """ generate hash sums for file """
+    ret = _get_external_file_sum(self, type, filename)
+    if not ret:
+        ret = _get_internal_file_sum(type, filename)
+    return ret
+
+def _get_internal_file_sum(type, filename):
+    """ generate hash sums for file with python modules """
+    if type == 'md5':
+        import md5
+        sum = md5.new()
+    elif type == 'sha1':
+        import sha
+        sum = sha.new()
+    elif type == 'sha256':
+        from Crypto.Hash import SHA256
+        sum = SHA256.new()
+    f = open(filename)
+    buf = f.read(8192)
+    while buf != '':
+        sum.update(buf)
+        buf = f.read(8192)
+    return sum.hexdigest()
+
+def _get_external_file_sum(self, type, filename):
+    """ generate hash sums for file with external programs """
+    ret = None
+    if os.access('/usr/bin/%ssum' % (type,), os.X_OK):
+        cmd = '/usr/bin/%ssum %s' % (type, filename,)
+        self._logger.debug("Running: %s" % (cmd,))
+        child = popen2.Popen3(cmd, 1)
+        child.tochild.close()
+        erroutput = child.childerr.read()
+        child.childerr.close()
+        if erroutput != '':
+            child.fromchild.close()
+            raise DinstallException("%ssum returned error output \"%s\"" % (type, erroutput,))
+        (sum, filename) = string.split(child.fromchild.read(), None, 1)
+        child.fromchild.close()
+        try:
+            status = child.wait()
+        except OSError, (errnum, err):
+            if errnum == 10:
+                logger.warn("Ignoring missing child proccess")
+                status = 0
+        if not (status is None or (os.WIFEXITED(status) and os.WEXITSTATUS(status) == 0)):
+            if os.WIFEXITED(status):
+                msg = "%ssum exited with error code %d" % (type, os.WEXITSTATUS(status),)
+            elif os.WIFSTOPPED(status):
+                msg = "%ssum stopped unexpectedly with signal %d" % (type, os.WSTOPSIG(status),)
+            elif os.WIFSIGNALED(status):
+                msg = "%ssum died with signal %d" % (type, os.WTERMSIG(status),)
+            raise DinstallException(msg)
+        ret = sum.strip()
+    return ret