From bece65fcbb0c895a03e87b45ad8e37883d8409af Mon Sep 17 00:00:00 2001
From: Yves Rizoud <yrizoud@gmail.com>
Date: Sat, 23 Jan 2010 18:33:48 +0000
Subject: [PATCH] Safety backup: On recovery, load all images even if it
 exceeds the normal setting of Backup Pages. On crash, do not attempt to save
 current visible image if the edited image has multiple layers.

git-svn-id: svn://pulkomandy.tk/GrafX2/trunk@1279 416bcca6-2ee7-4201-b75f-2eb2f807beb1
---
 loadsave.c | 33 +++++++++++++++++++++++----------
 loadsave.h |  3 +++
 2 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/loadsave.c b/loadsave.c
index 023e3be5..064b45b2 100644
--- a/loadsave.c
+++ b/loadsave.c
@@ -971,8 +971,10 @@ void Emergency_backup(const char *fname, byte *source, int width, int height, T_
 
 void Image_emergency_backup()
 {
-  Emergency_backup("a999999.bkp",Main_screen, Main_image_width, Main_image_height, &Main_palette);
-  Emergency_backup("b999999.bkp",Spare_screen, Spare_image_width, Spare_image_height, &Spare_palette);
+  if (Main_backups && Main_backups->Pages && Main_backups->Pages->Nb_layers == 1)
+    Emergency_backup("a999999.bkp",Main_screen, Main_image_width, Main_image_height, &Main_palette);
+  if (Spare_backups && Spare_backups->Pages && Spare_backups->Pages->Nb_layers == 1)
+    Emergency_backup("b999999.bkp",Spare_screen, Spare_image_width, Spare_image_height, &Spare_palette);
 }
 
 T_Format * Get_fileformat(byte format)
@@ -1131,6 +1133,16 @@ T_String_list *Backups_main = NULL;
 /// A list of files, used for scanning a directory
 T_String_list *Backups_spare = NULL;
 
+// Settings for safety backup (frequency, numbers, etc)
+
+const int Rotation_safety_backup = 8;
+
+const int Min_interval_for_safety_backup = 30000;
+const int Min_edits_for_safety_backup = 10;
+
+const int Max_interval_for_safety_backup = 60000;
+const int Max_edits_for_safety_backup = 30;
+
 ///
 /// Adds a file to Backups_main or Backups_spare lists, if it's a backup.
 ///
@@ -1193,10 +1205,16 @@ byte Process_backups(T_String_list **list)
   int i;
   char ** files_vector;
   T_String_list *element;
+  byte backup_max_undo_pages;
 
   if (*list == NULL)
     return 0;
 
+  // Save the maximum number of pages
+  // (It's used in Create_new_page() which gets called on each Load_image)
+  backup_max_undo_pages = Config.Max_undo_pages;
+  Config.Max_undo_pages = 99;
+
   // Count files
   nb_files=0;
   element=*list;
@@ -1240,6 +1258,9 @@ byte Process_backups(T_String_list **list)
   free(files_vector);
   files_vector = NULL;
   
+  // Restore the maximum number of pages
+  Config.Max_undo_pages = backup_max_undo_pages;
+  
   return nb_files;
 }
 
@@ -1289,14 +1310,6 @@ int Check_recovery(void)
   return restored_main || restored_spare;
 }
 
-const int Rotation_safety_backup = 8;
-
-const int Min_interval_for_safety_backup = 30000;
-const int Min_edits_for_safety_backup = 10;
-
-const int Max_interval_for_safety_backup = 60000;
-const int Max_edits_for_safety_backup = 30;
-
 void Rotate_safety_backups(void)
 {
   Uint32 now;
diff --git a/loadsave.h b/loadsave.h
index 8077a3ee..27b52bcc 100644
--- a/loadsave.h
+++ b/loadsave.h
@@ -146,6 +146,9 @@ extern T_Format File_formats[];
 ///
 /// Function which attempts to save backups of the images (main and spare),
 /// called in case of SIGSEGV.
+/// It will save an image only if it has just one layer... otherwise,
+/// the risk of flattening a layered image (or saving just one detail layer)
+/// is too high.
 void Image_emergency_backup(void);
 
 /// Load an arbitrary SDL_Surface.