[glom] Show correct error message when document could not be loaded from disk

[Armin Burgmeier <arminb src gnome org>]

commit 3bff83699f4bc3d89a7103ba3fe419a80f49f8bc
Author: Armin Burgmeier <armin arbur net>
Date:   Fri Jun 26 16:26:21 2009 +0200

    Show correct error message when document could not be loaded from disk
    
    	* glom/libglom/document/bakery/document.h: Document that failure_code
    	should be >= 1, so that we can detect whether the document could not
    	be opened because it couldn't be read from disk, or a custom error
    	code was set.
    
    	* glom/libglom/document/document.h: Set the value of
    	LOAD_FAILURE_CODE_FILE_VERSION_TOO_NEW to 1, to honor the requirement
    	explained above. This fixes showing the wrong error message when the
    	document could not be loaded from disk.

 ChangeLog                               |   12 ++++++++++++
 glom/libglom/document/bakery/document.h |    6 +++---
 glom/libglom/document/document.h        |    3 ++-
 3 files changed, 17 insertions(+), 4 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index 8f745f8..ec24b08 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,17 @@
 2009-06-26  Armin Burgmeier  <armin openismus com>
 
+	* glom/libglom/document/bakery/document.h: Document that failure_code
+	should be >= 1, so that we can detect whether the document could not
+	be opened because it couldn't be read from disk, or a custom error
+	code was set.
+
+	* glom/libglom/document/document.h: Set the value of
+	LOAD_FAILURE_CODE_FILE_VERSION_TOO_NEW to 1, to honor the requirement
+	explained above. This fixes showing the wrong error message when the
+	document could not be loaded from disk.
+
+2009-06-26  Armin Burgmeier  <armin openismus com>
+
 	* glom/application.cc (existing_or_new_new): When the new database
 	could be created successfully, then add the document to the recent
 	files list.
diff --git a/glom/libglom/document/bakery/document.h b/glom/libglom/document/bakery/document.h
index 5ca2b40..61dbf11 100644
--- a/glom/libglom/document/bakery/document.h
+++ b/glom/libglom/document/bakery/document.h
@@ -47,13 +47,13 @@ public:
 
   /* Loads data from disk, using the URI (set with set_file_uri()) then asks the View to update itself.
    * bool indicates success.
-   * @param failure_code Used to return a custom error code that is understood by your application.
+   * @param failure_code Used to return a custom error code that is understood by your application. This must be greater than zero.
    */
   bool load(int& failure_code);
 
   /* Loads data from disk, using the URI (set with set_file_uri()) then asks the View to update itself.
    * bool indicates success.
-   * @param failure_code Used to return a custom error code that is understood by your application.
+   * @param failure_code Used to return a custom error code that is understood by your application. This must be greater than zero.
    */
   bool load_from_data(const guchar* data, std::size_t length, int& failure_code);
 
@@ -111,7 +111,7 @@ protected:
 
   /** overrideable.
    * Does anything which should be done after the data has been loaded from disk, but before updating the View.
-   * @param failure_code Used to return a custom error code that is understood by your application.
+   * @param failure_code Used to return a custom error code that is understood by your application. This must be greater than zero.
    */
   virtual bool load_after(int& failure_code);
 
diff --git a/glom/libglom/document/document.h b/glom/libglom/document/document.h
index 9d1dad8..e2d4274 100644
--- a/glom/libglom/document/document.h
+++ b/glom/libglom/document/document.h
@@ -439,7 +439,8 @@ public:
   /// Failure codes that could be returned by load_after()
   enum load_failure_codes
   {
-    LOAD_FAILURE_CODE_FILE_VERSION_TOO_NEW
+    // The error codes must start at 1, so do that here:
+    LOAD_FAILURE_CODE_FILE_VERSION_TOO_NEW = 1
   };
 
 private: