Apply Nigel Titley's patch to fix #103174:

* src/register/register-core/basiccell.c:
	  - add some debugging messages
	  - don't kill ourself if we're asked to set the value to our own value.


git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@9224 57a11ea4-9604-0410-9ed3-97b8803252fd

ChangeLog

@@ -1,3 +1,24 @@
+2003-09-04  Derek Atkins  <derek@ihtfp.com>
+
+	Apply Nigel Titley's patch to fix #103174:
+	* src/register/register-core/basiccell.c:
+	  - add some debugging messages
+	  - don't kill ourself if we're asked to set the value to our own value.
+
+	Description of the problem from Nigel:
+	
+	The problem is that the SX formula_cell stuff calls (via an
+	intermediate step) 
+
+	gnc_basic_cell_set_value_internal (BasicCell *cell, const char *value)
+
+	with value pointing at cell->value. The overall effect of this as far
+	as gnc_basic_cell_set_value_internal is concerned is to trash the value
+	stored in cell->value *before* re-writing back to the same place (the
+	g_free() writes memory management stuff in the first few bytes of the
+	value). This is what trashes the debit/credit value in the SX register
+	entry.
+	
 2003-08-29  David Hampton  <hampton@employees.org>
 
 	* src/engine/Account.c: Fix bug in computing cleared balance.  The

src/register/register-core/basiccell.c

@@ -42,6 +42,8 @@
 #include "dialog-utils.h"
 #include "gnc-engine-util.h"
 
+/* Debugging module */
+static short module = MOD_REGISTER;
 
 gboolean
 gnc_cell_name_equal (const char * cell_name_1,
@@ -105,6 +107,7 @@ gnc_basic_cell_init (BasicCell *cell)
 void
 gnc_basic_cell_destroy (BasicCell *cell)
 {
+  ENTER(" ");
   if (cell->destroy)
     cell->destroy (cell);
 
@@ -124,6 +127,7 @@ gnc_basic_cell_destroy (BasicCell *cell)
 
   /* free the object itself */
   g_free (cell);
+  LEAVE(" ");
 }
 
 void
@@ -243,6 +247,14 @@ gnc_basic_cell_set_value_internal (BasicCell *cell, const char *value)
   if (value == NULL)
     value = "";
 
+  /* If the caller tries to set the value with our own value then do
+   * nothing because we have no work to do (or, at least, all the work
+   * will result in the status-quo, so why do anything?)  See bug
+   * #103174 and the description in the changelog on 2003-09-04.
+   */
+  if (cell->value == value)
+    return;
+
   g_free (cell->value);
   cell->value = g_strdup (value);