add a utility routine

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@1096 57a11ea4-9604-0410-9ed3-97b8803252fd

src/engine/Transaction.c

@@ -1142,5 +1142,19 @@ xaccGetOtherSplit (Split *split)
    return NULL;  /* never reached, in theory */
 }
 
+/********************************************************************\
+\********************************************************************/
+
+int
+xaccIsPeerSplit (Split *sa, Split *sb)
+{
+   Transaction *ta, *tb;
+   if (!sa || !sb) return 0;
+   ta = sa->parent;
+   tb = sb->parent;
+   if (ta == tb) return 1;
+   return 0;
+}
+
 /************************ END OF ************************************\
 \************************* FILE *************************************/

src/engine/Transaction.h

@@ -210,7 +210,7 @@ double xaccSplitGetClearedBalance (Split *);
 double xaccSplitGetReconciledBalance (Split *);
 double xaccSplitGetShareBalance (Split *);
 
-/* return teh parent transaction of the split */
+/* return the parent transaction of the split */
 Transaction * xaccSplitGetParent (Split *);
 
 /* return the memo, action strings */
@@ -257,9 +257,15 @@ Account * xaccGetAccountByName (Transaction *, const char *);
 
 /* 
  * The GetOtherSplit() is a convenience routine that returns
- * the other of a pair of splits.  If there are more than two 
- * splits, it returns NULL.
+ *    the other of a pair of splits.  If there are more than two 
+ *    splits, it returns NULL.
  */
 Split * xaccGetOtherSplit (Split *);
 
+/* The IsPeerSplit() is a convenience routine that returns
+ *    a non-zero value if the two splits share a common 
+ *    parent transaction, else it returns zero.
+ */
+int xaccIsPeerSplit (Split *, Split *);
+
 #endif /* __XACC_TRANSACTION_H__ */