Customize the srpm method, this lets us accommodate the CentOS directory structure

The vanilla rpkg instance dumps all the sources in the toplevel of the
package checkout (everything is flat). CentOS uses the
SOURCES,SPECS,SRPMS directory structure.

src/centpkg/__init__.py

@@ -145,6 +145,37 @@ class Commands(pyrpkg.Commands):
 
         return
 
+    def srpm(self, hashtype=None):
+        """Create an srpm using hashtype from content in the module
+
+        Requires sources already downloaded.
+        """
+
+        # This line is what changed for centpkg, in Fedora the directory
+        # structure is flat, in CentOS we use the proper SRPMS/ directory for
+        # our source RPMs 
+        self.srpmname = os.path.join(self.path, 'SRPMS',
+                            "{0}-{1}-{2}.src.rpm".format(self.module_name,
+                                                  self.ver, self.rel))
+        # See if we need to build the srpm
+        if os.path.exists(self.srpmname):
+            self.log.debug('Srpm found, rewriting it.')
+
+        cmd = ['rpmbuild']
+        cmd.extend(self.rpmdefines)
+        if self.quiet:
+            cmd.append('--quiet')
+        # Figure out which hashtype to use, if not provided one
+        if not hashtype:
+            # Try to determine the dist
+            hashtype = self._guess_hashtype()
+        # This may need to get updated if we ever change our checksum default
+        if not hashtype == 'sha256':
+            cmd.extend(["--define '_source_filedigest_algorithm %s'" % hashtype,
+                    "--define '_binary_filedigest_algorithm %s'" % hashtype])
+        cmd.extend(['--nodeps', '-bs', os.path.join(self.path, self.spec)])
+        self._run_command(cmd, shell=True)
+
     # These are the commands defined in the base pyrpkg.Commands class
     # and have not been implemented here, yet
 
@@ -202,9 +233,6 @@ class Commands(pyrpkg.Commands):
     def prep(self, *args, **kwargs):
         raise NotImplementedError("This command is not yet implemented in centpkg")
 
-    def srpm(self, *args, **kwargs):
-        raise NotImplementedError("This command is not yet implemented in centpkg")
-
     def unused_patches(self, *args, **kwargs):
         raise NotImplementedError("This command is not yet implemented in centpkg")