Huge rewrite of the file loading/saving system. Normally safer in case of problem. Added incremental safety backups at regular intervals in the 'application data' directory (Windows) or $HOME/.grafx2 (unix). Keeps 8 files, saves every 30-60s and/or every 10-30 clicks.

git-svn-id: svn://pulkomandy.tk/GrafX2/trunk@1245 416bcca6-2ee7-4201-b75f-2eb2f807beb1

loadsave.h

@@ -24,30 +24,108 @@
 /// Also handles showing the preview in fileselectors.
 //////////////////////////////////////////////////////////////////////////////
 
+#ifndef __LOADSAVE_H__
+#define __LOADSAVE_H__
+
+#include <stdio.h>
+
+enum CONTEXT_TYPE {
+  CONTEXT_MAIN_IMAGE,
+  CONTEXT_BRUSH,
+  CONTEXT_PREVIEW,
+};
+
+
+typedef struct
+{
+  /// Kind of context. Internally used to differentiate the "sub-classes"
+  enum CONTEXT_TYPE Type;
+  
+  // File properties
+  
+  char * File_name;
+  char * File_directory;
+  byte Format;
+  
+  // Image properties
+  
+  T_Palette Palette;
+  short Width;
+  short Height;
+  byte Nb_layers;
+  char Comment[COMMENT_SIZE+1];
+  short Transparent_color;
+  /// Pixel ratio of the image
+  enum PIXEL_RATIO Ratio;
+  
+  /// Load/save address of first pixel
+  byte *Target_address;
+  /// Pitch: Difference of addresses between one pixel and the one just "below" it
+  long Pitch;
+  
+  /// Internal: Used to mark truecolor images on loading. Only used by preview.
+  //byte Is_truecolor;
+  /// Internal: Temporary RGB buffer when loading 24bit images
+  T_Components *Buffer_image_24b;
+  
+  /// Internal: Temporary buffer when saving the flattened copy of something
+  byte *Buffer_image;
+  
+  // Internal: working data for preview case
+  short Preview_factor_X;
+  short Preview_factor_Y;
+  short Preview_pos_X;
+  short Preview_pos_Y;
+
+} T_IO_Context;
+
+/// Type of a function that can be called for a T_IO_Context. Kind of a method.
+typedef void (* Func_IO) (T_IO_Context *);
+
+/*
 void Pixel_load_in_current_screen (word x_pos, word y_pos, byte color);
 void Pixel_load_in_preview (word x_pos, word y_pos, byte color);
 void Pixel_load_in_brush (word x_pos, word y_pos, byte color);
+*/
 
-void Get_full_filename(char * filename, byte is_colorix_format);
+// Setup for loading a preview in fileselector
+void Init_context_preview(T_IO_Context * context, char *file_name, char *file_directory);
+// Setup for loading/saving the current main image
+void Init_context_layered_image(T_IO_Context * context, char *file_name, char *file_directory);
+// Setup for loading/saving the flattened version of current main image
+void Init_context_flat_image(T_IO_Context * context, char *file_name, char *file_directory);
+// Setup for loading/saving the user's brush
+void Init_context_brush(T_IO_Context * context, char *file_name, char *file_directory);
+// Setup for saving an arbitrary undo/redo step, from either the main or spare page. 
+void Init_context_history_step(T_IO_Context * context, T_Page *page);
+
+// Cleans up resources (currently: the 24bit buffer) 
+void Destroy_context(T_IO_Context *context);
 
 ///
 /// High-level picture loading function.
-/// Handles loading an image or a brush, or previewing only.
-/// @param image true if the fileselector is the one for loading images (not brush)
-void Load_image(byte image);
+void Load_image(T_IO_Context *context);
 
 ///
 /// High-level picture saving function.
-/// @param image true if the image should be saved (instead of the brush)
-void Save_image(byte image);
+void Save_image(T_IO_Context *context);
+
+///
+/// Checks if there are any pending safety backups, and then opens them.
+/// Returns 0 if there were none
+/// Returns non-zero if some backups were loaded.
+int Check_recovery(void);
+
+/// Remove safety backups. Need to call on normal program exit.
+void Delete_safety_backups(void);
 
 /// Data for an image file format.
 typedef struct {
   byte Identifier;         ///< Identifier for this format in enum :FILE_FORMATS
   char *Label;             ///< Five-letter label
-  Func_action Test;        ///< Function which tests if the file is of this format
-  Func_action Load;        ///< Function which loads an image of this format
-  Func_action Save;        ///< Function which saves an image of this format
+  Func_IO Test;            ///< Function which tests if the file is of this format
+  Func_IO Load;            ///< Function which loads an image of this format
+  Func_IO Save;            ///< Function which saves an image of this format
   byte Palette_only;       ///< Boolean, true if this format saves/loads only the palette.
   byte Comment;            ///< This file format allows a text comment
   byte Supports_layers;    ///< Boolean, true if this format preserves layers on saving
@@ -63,8 +141,10 @@ extern T_Format File_formats[];
 /// called in case of SIGSEGV.
 void Image_emergency_backup(void);
 
+/*
 /// Pixel ratio of last loaded image: one of :PIXEL_SIMPLE, :PIXEL_WIDE or :PIXEL_TALL
 extern enum PIXEL_RATIO Ratio_of_loaded_image;
+*/
 
 T_Format * Get_fileformat(byte format);
 
@@ -77,6 +157,25 @@ T_Format * Get_fileformat(byte format);
 #define NB_KNOWN_FORMATS 18 ///< Total number of known file formats.
 #endif
 
+// Internal use
+
+/// Generic allocation and similar stuff, done at beginning of image load, as soon as size is known.
+void Pre_load(T_IO_Context *context, short width, short height, long file_size, int format, enum PIXEL_RATIO ratio, byte truecolor);
+/// Remaps the window. To call after palette (last) changes.
+void Remap_fileselector(T_IO_Context *context);
+/// Generic cleanup done on end of loading (ex: color-conversion from the temporary 24b buffer)
+//void Post_load(T_IO_Context *context);
+
+/// Query the color of a pixel (to save)
+byte Get_pixel(T_IO_Context *context, short x, short y);
+/// Set the color of a pixel (on load)
+void Set_pixel(T_IO_Context *context, short x, short y, byte c);
+/// Set the color of a 24bit pixel (on load)
+void Set_pixel_24b(T_IO_Context *context, short x, short y, byte r, byte g, byte b);
+/// Function to call when need to switch layers.
+void Set_layer(T_IO_Context *context, byte layer);
+
+
 // =================================================================
 // What follows here are the definitions of functions and data
 // useful for fileformats.c, miscfileformats.c etc.
@@ -96,6 +195,7 @@ typedef struct
 
 // Data for 24bit loading
 
+/*
 typedef void (* Func_24b_display) (short,short,byte,byte,byte);
 
 extern int Image_24b;
@@ -104,14 +204,16 @@ extern Func_24b_display Pixel_load_24b;
 
 void Init_preview_24b(short width,short height,long size,int format);
 void Pixel_load_in_24b_preview(short x_pos,short y_pos,byte r,byte g,byte b);
-
+*/
 //
 
 void Set_file_error(int value);
-void Init_preview(short width,short height,long size,int format,enum PIXEL_RATIO ratio);
 
+/*
+void Init_preview(short width,short height,long size,int format,enum PIXEL_RATIO ratio);
+*/
 void Init_write_buffer(void);
 void Write_one_byte(FILE *file, byte b);
 void End_write(FILE *file);
 
-void Remap_fileselector(void);
+#endif