Automatically save a snapshot when close()'ing a project.

This snapshot, if up-to-date, may be used to accellerate loading of
projects with very long histories.

Timeline/Loggable.C

@@ -25,6 +25,8 @@
 #include <stdarg.h>
 #include <string.h>
 
+#include "util/file.h"
+
 #include <algorithm>
 using std::min;
 using std::max;
@@ -49,34 +51,57 @@ Loggable::open ( const char *filename )
 {
     FILE *fp;
 
+    Loggable::_fp = NULL;
+
     if ( ! ( fp = fopen( filename, "a+" ) ) )
     {
         WARNING( "Could not open log file for writing!" );
         return false;
     }
 
-    /* replay log */
+    if ( newer( "snapshot", filename ) )
     {
-        /* FIXME: bogus */
-        char buf[BUFSIZ];
+        DMESSAGE( "Loading snapshot" );
 
-        while ( fscanf( fp, "%[^\n]\n", buf ) == 1 )
-        {
-            if ( ! ( ! strcmp( buf, "{" ) || ! strcmp( buf, "}" ) ) )
-            {
-                if ( *buf == '\t' )
-                    do_this( buf + 1, false );
-                else
-                    do_this( buf, false );
-            }
-        }
+        FILE *fp = fopen( "snapshot", "r" );
+
+        replay( fp );
+
+        fclose( fp );
+    }
+    else
+    {
+        DMESSAGE( "Replaying journal" );
+
+        replay( fp );
     }
 
+    fseek( fp, 0, SEEK_END );
+
     Loggable::_fp = fp;
 
     return true;
 }
 
+/** replay journal or snapshot */
+bool
+Loggable::replay ( FILE *fp )
+{
+    /* FIXME: bogus */
+    char buf[BUFSIZ];
+
+    while ( fscanf( fp, "%[^\n]\n", buf ) == 1 )
+    {
+        if ( ! ( ! strcmp( buf, "{" ) || ! strcmp( buf, "}" ) ) )
+        {
+            if ( *buf == '\t' )
+                do_this( buf + 1, false );
+            else
+                do_this( buf, false );
+        }
+    }
+}
+
 /** close journal and delete all loggable objects, returing the systemt to a blank slate */
 bool
 Loggable::close ( void )
@@ -91,6 +116,8 @@ Loggable::close ( void )
 
     _fp = NULL;
 
+    snapshot( "snapshot" );
+
     for ( int i = 0; i < _log_id - 1; ++i )
     {
         Loggable ** l = &_loggables[ i ];
@@ -333,10 +360,11 @@ Loggable::undo ( void )
     delete[] buf;
 }
 
+/* FIXME: we need a version of this that is fully const, right? */
 /** write a snapshot of the state of all loggable objects, sufficient
  * for later reconstruction, to /fp/ */
 bool
-Loggable::snapshot( FILE *fp )
+Loggable::snapshot ( FILE *fp )
 {
     FILE *ofp = _fp;
 
@@ -380,6 +408,19 @@ Loggable::snapshot( FILE *fp )
     return true;
 }
 
+bool
+Loggable::snapshot ( const char *name )
+{
+    FILE *fp;
+
+    if ( ! ( fp = fopen( name, "w" ) ))
+        return false;
+
+    snapshot( fp );
+
+    fclose( fp );
+}
+
 /** Replace the journal with a snapshot of the current state */
 void
 Loggable::compact ( void )
@@ -396,6 +437,9 @@ Loggable::compact ( void )
 void
 Loggable::log ( const char *fmt, ... )
 {
+    if ( ! _fp )
+        return;
+
     /* FIXME: bogus limit  */
     static char buf[1024];
     static int i = 0;
@@ -490,7 +534,7 @@ Loggable::log_print( const Log_Entry *o, const Log_Entry *n ) const
 
             o->get( i, &s, &v );
 
-            log( "%s %s%s", s, o->size() == i + 1 ? "" : " " );
+            log( "%s %s%s", s, v, o->size() == i + 1 ? "" : " " );
         }
     }
 
@@ -550,13 +594,20 @@ Loggable::log_end ( void )
 void
 Loggable::log_create ( void ) const
 {
+    if ( ! _fp )
+        /* replaying, don't bother */
+
+        return;
     log( "%s 0x%X create ", class_name(), _id );
 
     Log_Entry e;
 
     get( e );
 
-    log_print( NULL, &e );
+    if ( e.size() )
+        log_print( NULL, &e );
+    else
+        log( "\n" );
 
     if ( Loggable::_level == 0 )
         Loggable::flush();

Timeline/Loggable.H

@@ -104,16 +104,10 @@ private:
     static void log ( const char *fmt, ... );
 
     static void flush ( void );
-    static
-    void indent ( void )
-        {
-            int n = Loggable::_level;
-
-            while ( n-- )
-                log( "\t" );
-        }
 
     static bool snapshot( FILE * fp );
+    static bool snapshot( const char *name );
+    static bool replay ( FILE *fp );
 
     void init ( bool loggable=true )
         {

Timeline/makefile.inc

@@ -4,7 +4,7 @@ Timeline_VERSION := 0.5.0
 
 Timeline_SRCS := $(wildcard Timeline/*.C Timeline/*.fl Timeline/Engine/*.C)
 
-Timeline_SRCS += util/debug.C util/Thread.C
+Timeline_SRCS += util/debug.C util/Thread.C util/file.C
 
 Timeline_SRCS:=$(Timeline_SRCS:.fl=.C)
 Timeline_SRCS:=$(sort $(Timeline_SRCS))

util/file.C

@@ -0,0 +1,40 @@
+
+/*******************************************************************************/
+/* Copyright (C) 2008 Jonathan Moore Liles                                     */
+/*                                                                             */
+/* This program is free software; you can redistribute it and/or modify it     */
+/* under the terms of the GNU General Public License as published by the       */
+/* Free Software Foundation; either version 2 of the License, or (at your      */
+/* option) any later version.                                                  */
+/*                                                                             */
+/* This program is distributed in the hope that it will be useful, but WITHOUT */
+/* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or       */
+/* FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for   */
+/* more details.                                                               */
+/*                                                                             */
+/* You should have received a copy of the GNU General Public License along     */
+/* with This program; see the file COPYING.  If not,write to the Free Software */
+/* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+/*******************************************************************************/
+
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+long
+mtime ( const char *file )
+{
+    struct stat st;
+
+    if ( stat( file, &st ) )
+        return 0;
+
+    return st.st_mtime;
+}
+
+/** returns /true/ if /file1/ is newer than /file2/ (or file2 doesn't exist) */
+bool
+newer ( const char *file1, const char *file2 )
+{
+    return mtime( file1 ) > mtime( file2 );
+}

util/file.h

@@ -0,0 +1,21 @@
+
+/*******************************************************************************/
+/* Copyright (C) 2008 Jonathan Moore Liles                                     */
+/*                                                                             */
+/* This program is free software; you can redistribute it and/or modify it     */
+/* under the terms of the GNU General Public License as published by the       */
+/* Free Software Foundation; either version 2 of the License, or (at your      */
+/* option) any later version.                                                  */
+/*                                                                             */
+/* This program is distributed in the hope that it will be useful, but WITHOUT */
+/* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or       */
+/* FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for   */
+/* more details.                                                               */
+/*                                                                             */
+/* You should have received a copy of the GNU General Public License along     */
+/* with This program; see the file COPYING.  If not,write to the Free Software */
+/* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+/*******************************************************************************/
+
+long mtime ( const char *file );
+bool newer ( const char *file1, const char *file2 );