[Tuxnes-devel] Code Sharing Patch

[W. M. P. <mi...@fl...>]

Enclosed you should find a patch to TuxNES 0.75 that attempts to share
code between renderers at bit more.  It adds a file named renderer_util.c
that is a collection of functions used by the renderers.

This patch requires my SDL patch, which I emailed to this mailing list
a few days ago.  My SDL patch is also available at http://www.flyn.org.

I have not tested the trivial changes to w.c and ggi.c, as I do not use
these systems.

Please let me know what you think.

================================================================================

diff -u --new-file --recursive tuxnes-0.75-sdl/Makefile.am tuxnes-0.75-codeshare/Makefile.am
--- tuxnes-0.75-sdl/Makefile.am	Sun Mar 24 17:34:31 2002
+++ tuxnes-0.75-codeshare/Makefile.am	Sun Mar 24 16:28:43 2002
@@ -6,8 +6,8 @@
 
 tuxnes_SOURCES = x86.S d6502.c dynrec.c emu.c fb.c gamegenie.c io.c mapper.c \
 	sdl.c sound.c sound.h ggi.c x11.c w.c consts.h gamegenie.h globals.h \
-	mapper.h renderer.c renderer.h ntsc_pal.c unzip.c unzip.h \
-	ziploader.c ziploader.h
+	mapper.h renderer.c renderer.h renderer_util.c ntsc_pal.c unzip.c \
+	unzip.h ziploader.c ziploader.h
 EXTRA_tuxnes_SOURCES = pixels.h
 tuxnes_LDADD = table.o
 
diff -u --new-file --recursive tuxnes-0.75-sdl/ggi.c tuxnes-0.75-codeshare/ggi.c
--- tuxnes-0.75-sdl/ggi.c	Wed Apr 11 23:45:47 2001
+++ tuxnes-0.75-codeshare/ggi.c	Sun Mar 24 17:31:06 2002
@@ -20,8 +20,6 @@
 #include <unistd.h>
 #include <sys/stat.h>
 #include <sys/types.h>
-#include <sys/time.h>
-#include <dirent.h>
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -1047,8 +1045,7 @@
   ggiFillscreen (visualGGI);
   ggiSetGCForeground (visualGGI, whitepixel);
   ggiFlush (visualGGI);
-  gettimeofday (&time, NULL);
-  renderer_data.basetime = time.tv_sec;
+  set_renderer_basetime();
   return 0;
 }
 
@@ -1145,24 +1142,7 @@
 
   /* do audio update */
   UpdateAudio();
-
-  /* Check the time.  If we're getting behind, skip a frame to stay in sync. */
-  gettimeofday (&time, NULL);
-  timeframe = (time.tv_sec - renderer_data.basetime) * 50 + time.tv_usec / 20000;     /* PAL */
-  timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;     /* NTSC */
-  frame++;
-  if (halfspeed)
-    timeframe >>= 1;
-  if (doublespeed == 2)
-    timeframe <<= 1;
-  else if (doublespeed > 2)
-    timeframe *= doublespeed;
-  if (desync)
-    frame = timeframe;
-  desync = 0;
-  if (frame < timeframe - 20 && frame % 20 == 0)
-    desync = 1;                 /* If we're more than 20 frames behind, might as well stop counting. */
-
+  set_timeframe(&frame, &timeframe, &desync);
   if (! nodisplay)
     {
       drawimage (PBL);
@@ -1281,13 +1261,7 @@
   needsredraw = 0;
   redrawbackground = 0;
   redrawall = 0;
-
-  /* Slow down if we're getting ahead */
-  if (frame > timeframe + 1 && frameskip == 0)
-    {
-      usleep (16666 * (frame - timeframe - 1));
-    }
-
+  resynchronize(frame, timeframe, frameskip);
   /* Input loop */
   do {
     struct timeval tv = { 0, 0 };
@@ -1310,20 +1284,7 @@
       HandleKeyboardGGI (ev);
     }
   } while (renderer_data.pause_display);
-  
-  /* Check the time.  If we're getting behind, skip next frame to stay in sync. */
-  gettimeofday (&time, NULL);
-  timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;     /* NTSC */
-  if (halfspeed)
-    timeframe >>= 1;
-  if (doublespeed == 2)
-    timeframe <<= 1;
-  else if (doublespeed > 2)
-    timeframe *= doublespeed;
-  if (frame >= timeframe || frame % 20 == 0)
-    frameskip = 0;
-  else
-    frameskip = 1;
+  set_frameskip (frame, &timeframe, &frameskip);  
 }
 
 #endif
diff -u --new-file --recursive tuxnes-0.75-sdl/renderer.c tuxnes-0.75-codeshare/renderer.c
--- tuxnes-0.75-sdl/renderer.c	Sun Mar 24 17:34:31 2002
+++ tuxnes-0.75-codeshare/renderer.c	Sun Mar 24 17:29:49 2002
@@ -204,24 +204,7 @@
 
   /* do audio update */
   UpdateAudio();
-
-  /* Check the time.  If we're getting behind, skip a frame to stay in sync. */
-  gettimeofday (&time, NULL);
-  timeframe = (time.tv_sec - renderer_data.basetime) * 50 + time.tv_usec / 20000;     /* PAL */
-  timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;     /* NTSC */
-  frame++;
-  if (halfspeed)
-    timeframe >>= 1;
-  if (doublespeed == 2)
-    timeframe <<= 1;
-  else if (doublespeed > 2)
-    timeframe *= doublespeed;
-  if (desync)
-    frame = timeframe;
-  desync = 0;
-  if (frame < timeframe - 20 && frame % 20 == 0)
-    desync = 1;                 /* If we're more than 20 frames behind, might as well stop counting. */
-
+  set_timeframe(&frame, &timeframe, &desync);
   /* Slow down if we're getting ahead */
   if (frame > timeframe + 1 && frameskip == 0)
     {
@@ -240,20 +223,7 @@
 	HandleJoystickLinux(1);
       }
   } while (renderer_data.pause_display);
-
-  /* Check the time.  If we're getting behind, skip next frame to stay in sync. */
-  gettimeofday (&time, NULL);
-  timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;     /* NTSC */
-  if (halfspeed)
-    timeframe >>= 1;
-  if (doublespeed == 2)
-    timeframe <<= 1;
-  else if (doublespeed > 2)
-    timeframe *= doublespeed;
-  if (frame >= timeframe || frame % 20 == 0)
-    frameskip = 0;
-  else
-    frameskip = 1;
+  set_frameskip (frame, &timeframe, &frameskip);
 }
 
 /* Update the colors on the screen if the palette changed */
diff -u --new-file --recursive tuxnes-0.75-sdl/renderer_util.c tuxnes-0.75-codeshare/renderer_util.c
--- tuxnes-0.75-sdl/renderer_util.c	Thu Jan  1 01:00:00 1970
+++ tuxnes-0.75-codeshare/renderer_util.c	Sun Mar 24 17:27:28 2002
@@ -0,0 +1,130 @@
+/*
+ * This file is part of the TuxNES project codebase.
+ *
+ * Please see the README and COPYING files for more information regarding
+ * this project.
+ *
+ * Description: Shared code used by all of the tuxnes renderers.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif				/* HAVE_CONFIG_H */
+
+#include <dirent.h>
+#include <sys/stat.h>
+#include <string.h>
+#include <stdlib.h>
+#include <globals.h>
+#include <stdio.h>
+#include <sys/time.h>
+#include <renderer.h>
+#include <unistd.h>
+
+/* ============================ screenshot_init () ========================= */
+void screenshot_init(char *ext, char **ssfile, int *ssnumber)
+{
+    DIR *dir;
+    struct dirent *dirp;
+    int currentnumber = 0;
+    /* Allocate space for (tuxnesdir) + (basefilename-snap-xxxx.ext) + ('\0') */
+    if ((*ssfile = (char *) malloc(strlen(tuxnesdir) +
+				   strlen(basefilename) + 1 + 4 +
+				   1 + 4 + 1 + 3 + 1)) == NULL) {
+	perror("malloc");
+	exit(1);
+    }
+    sprintf(*ssfile, "%s-snap-", basefilename);
+    /* open the screenshot directory */
+    if ((dir = opendir(tuxnesdir)) == NULL) {
+	return;
+    }
+    /* iterate through the files and establish the starting screenshot number */
+    while ((dirp = readdir(dir)) != NULL) {
+	if ((strlen(dirp->d_name) >= 8)
+	    && (strncmp(dirp->d_name, *ssfile, strlen(*ssfile))
+		== 0)
+	    &&
+	    (strncmp
+	     (dirp->d_name + strlen(dirp->d_name) - 4, ext,
+	      strlen(ext)) == 0)) {
+	    dirp->d_name[strlen(dirp->d_name) - 4] = '\0';
+	    if ((currentnumber =
+		 atoi(dirp->d_name + strlen(*ssfile))) > *ssnumber) {
+		*ssnumber = currentnumber;
+	    }
+	}
+    }
+    if (++*ssnumber > 9999) {
+	*ssnumber = 0;
+    }
+    closedir(dir);
+}
+
+/* ============================ screenshot_check_filename () =============== */
+void screenshot_check_filename(char *ext, char *ssfile, int *ssnumber)
+{
+    /* make sure we don't over-write screenshots written by a concurrent TuxNES process */
+    {
+	struct stat buf[1];
+	do
+	    sprintf(ssfile, "%s%s-snap-%04u%s", tuxnesdir,
+		    basefilename, *ssnumber++, ext);
+	while ((!stat(ssfile, buf)) && !(*ssnumber > 9999));
+    }
+    if (*ssnumber > 9999)
+	*ssnumber = 0;
+}
+
+/* ============================ set_renderer_basetime () =================== */
+void set_renderer_basetime(void)
+{
+    struct timeval time;
+    gettimeofday(&time, NULL);
+    renderer_data.basetime = time.tv_sec;
+}
+
+/* ============================ set_frameskip () =========================== */
+void set_frameskip(int frame, int *timeframe, int *frameskip)
+{
+    struct timeval time;
+    gettimeofday(&time, NULL);
+    *timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;	/* NTSC */
+    if (halfspeed)
+	*timeframe >>= 1;
+    if (doublespeed == 2)
+	*timeframe <<= 1;
+    else if (doublespeed > 2)
+	*timeframe *= doublespeed;
+    if (frame >= *timeframe || frame % 20 == 0)
+	*frameskip = 0;
+    else
+	*frameskip = 1;
+
+}
+
+/* ============================ set_timeframe () =========================== */
+void set_timeframe(int *frame, int *timeframe, int *desync)
+{
+    struct timeval time;
+    gettimeofday(&time, NULL);
+    *timeframe = (time.tv_sec - renderer_data.basetime) * 50 + time.tv_usec / 20000;	/* PAL */
+    *timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;	/* NTSC */
+    (*frame)++;
+    if (halfspeed)
+	*timeframe >>= 1;
+    if (doublespeed > 1)
+	*timeframe *= doublespeed;
+    if (*desync)
+	*frame = *timeframe;
+    *desync = 0;
+    if (*frame < *timeframe - 20 && *frame % 20 == 0)
+	*desync = 1;		/* If we're more than 20 frames behind, might as well stop counting. */
+}
+
+/* ============================ resynchronize () =========================== */
+void resynchronize(int frame, int timeframe, int frameskip)
+{
+    if (frame > timeframe + 1 && frameskip == 0)
+	usleep(16666 * (frame - timeframe - 1));
+}
diff -u --new-file --recursive tuxnes-0.75-sdl/renderer_util.h tuxnes-0.75-codeshare/renderer_util.h
--- tuxnes-0.75-sdl/renderer_util.h	Thu Jan  1 01:00:00 1970
+++ tuxnes-0.75-codeshare/renderer_util.h	Sun Mar 24 17:27:57 2002
@@ -0,0 +1,31 @@
+/*
+ * This file is part of the TuxNES project codebase.
+ *
+ * Please see the README and COPYING files for more information regarding
+ * this project.
+ *
+ * Description: Shared code used by all of the tuxnes renderers.
+ */
+
+#ifndef _RENDERER_UTIL_H
+#define _RENDERER_UTIL_H
+
+/* ============================ screenshot_init () ========================= */ 
+void screenshot_init(char *ext, char **ssfile, int *ssnumber);
+
+/* ============================ screenshot_check_filename () =============== */ 
+void screenshot_check_filename(char *ext, char *ssfile, int *ssnumber);
+
+/* ============================ set_renderer_basetime () =================== */
+void set_renderer_basetime(void);
+
+/* ============================ set_frameskip () =========================== */
+void set_frameskip(int frame, int *timeframe, int *frameskip);
+
+/* ============================ set_timeframe () =========================== */
+void set_timeframe(int *frame, int *timeframe, int *desync);
+
+/* ============================ resynchronize () =========================== */
+void resynchronize (int frame, int timeframe, int frameskip);
+
+#endif /* RENDERER_UTIL_H */
diff -u --new-file --recursive tuxnes-0.75-sdl/sdl.c tuxnes-0.75-codeshare/sdl.c
--- tuxnes-0.75-sdl/sdl.c	Sun Mar 24 17:34:31 2002
+++ tuxnes-0.75-codeshare/sdl.c	Sun Mar 24 17:31:39 2002
@@ -19,6 +19,7 @@
 #include "globals.h"
 #include "mapper.h"
 #include "renderer.h"
+#include "renderer_util.h"
 #include "sound.h"
 
 #ifdef HAVE_SDL
@@ -27,12 +28,8 @@
 #include <SDL/SDL_endian.h>
 #include <stdlib.h>
 #include <string.h>
-#include <sys/time.h>
 #include <unistd.h>
 
-/* FIXME: Share with x11.c, w.c, etc. */
-#include <dirent.h>
-#include <sys/stat.h>
 char    *screenshotfile;
 static int     screenshotnumber = 0;
 
@@ -41,64 +38,10 @@
 SDL_Surface *screen;
 unsigned int paletteSDL[64];
 
-/* ============================ InitScreenshotSDL () ======================= */
-static void InitScreenshotSDL(void)
-{
-    DIR *dir;
-    struct dirent *dirp;
-    int currentnumber = 0;
-    /* Allocate space for (tuxnesdir) + (basefilename-snap-xxxx.bmp) + ('\0') */
-    if ((screenshotfile = (char *) malloc(strlen(tuxnesdir) +
-					  strlen(basefilename) + 1 + 4 +
-					  1 + 4 + 1 + 3 + 1)) == NULL) {
-	perror("malloc");
-	exit(1);
-    }
-    sprintf(screenshotfile, "%s-snap-", basefilename);
-    /* open the screenshot directory */
-    if ((dir = opendir(tuxnesdir)) == NULL) {
-	return;
-    }
-    /* iterate through the files and establish the starting screenshot number */
-    while ((dirp = readdir(dir)) != NULL) {
-	if ((strlen(dirp->d_name) >= 8)
-	    &&
-	    (strncmp(dirp->d_name, screenshotfile, strlen(screenshotfile))
-	     == 0)
-	    &&
-	    (strncmp
-	     (dirp->d_name + strlen(dirp->d_name) - 4, ".bmp",
-	      strlen(".bmp")) == 0)) {
-	    dirp->d_name[strlen(dirp->d_name) - 4] = '\0';
-	    if ((currentnumber =
-		 atoi(dirp->d_name + strlen(screenshotfile))) >
-		screenshotnumber) {
-		screenshotnumber = currentnumber;
-	    }
-	}
-    }
-    if (++screenshotnumber > 9999) {
-	screenshotnumber = 0;
-    }
-    closedir(dir);
-}
-
-
 /* ============================ SaveScreenshotSDL () ======================= */
 static void SaveScreenshotSDL(void)
 {
-    int status;
-    /* make sure we don't over-write screenshots written by a concurrent TuxNES process */
-    {
-	struct stat buf[1];
-	do
-	    sprintf(screenshotfile, "%s%s-snap-%04u.bmp", tuxnesdir,
-		    basefilename, screenshotnumber++);
-	while ((!stat(screenshotfile, buf)) && !(screenshotnumber > 9999));
-    }
-    if (screenshotnumber > 9999) {
-	screenshotnumber = 0;
-    }
+    screenshot_check_filename (".bmp", screenshotfile, &screenshotnumber);
     SDL_SaveBMP(screen, screenshotfile);
 }
 
@@ -106,7 +49,6 @@
 int InitDisplaySDL(int argc, char **argv)
 {
     int i;
-    struct timeval time;
     if (magstep < 1)
 	magstep = 1;
     if (magstep > maxsize) {
@@ -128,7 +70,7 @@
 		SDL_GetError());
 	exit(1);
     }
-    SDL_WM_ToggleFullScreen(screen);
+    //SDL_WM_ToggleFullScreen(screen);
     rfb = fb = screen->pixels;
     for (i = 0; i < 64; i++) {
 	unsigned char r, g, b;
@@ -138,9 +80,8 @@
 	paletteSDL[i] = (r << 11) | (g << 5) | (b);
     }
     fbinit();
-    InitScreenshotSDL();
-    gettimeofday(&time, NULL);
-    renderer_data.basetime = time.tv_sec;
+    screenshot_init(".bmp", &screenshotfile, &screenshotnumber);
+    set_renderer_basetime();
     return 0;
 }
 
@@ -346,34 +287,18 @@
 /* ============================ UpdateDisplaySDL () ======================== */
 void UpdateDisplaySDL(void)
 {
-    struct timeval time;
     unsigned static int frame;
     unsigned int timeframe;
     SDL_Event event;
     /* FIXME: Write SDL audio handler */
     UpdateAudio();
-    gettimeofday(&time, NULL);
-    timeframe = (time.tv_sec - renderer_data.basetime) * 50 + time.tv_usec / 20000;	/* PAL */
-    timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;	/* NTSC */
-    frame++;
-    if (halfspeed)
-	timeframe >>= 1;
-    if (doublespeed == 2)
-	timeframe <<= 1;
-    else if (doublespeed > 2)
-	timeframe *= doublespeed;
-    if (desync)
-	frame = timeframe;
-    desync = 0;
-    if (frame < timeframe - 20 && frame % 20 == 0)
-	desync = 1;		/* If we're more than 20 frames behind, might as well stop counting. */
+
+    set_timeframe(&frame, &timeframe, &desync);
     drawimage(PBL);
     if (!frameskip) {
 	SDL_UpdateRect(screen, 0, 0, 0, 0);
     }
-    if (frame > timeframe + 1 && frameskip == 0) {
-	usleep(16666 * (frame - timeframe - 1));
-    }
+    resynchronize(frame, timeframe, frameskip);
 
     /* FIXME: write SDL handler */
     if (jsfd[0] >= 0)
@@ -392,19 +317,7 @@
 	    exit(0);
 	}
     }
-
-    gettimeofday(&time, NULL);
-    timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;	/* NTSC */
-    if (halfspeed)
-	timeframe >>= 1;
-    if (doublespeed == 2)
-	timeframe <<= 1;
-    else if (doublespeed > 2)
-	timeframe *= doublespeed;
-    if (frame >= timeframe || frame % 20 == 0)
-	frameskip = 0;
-    else
-	frameskip = 1;
+  set_frameskip (frame, &timeframe, &frameskip);
 }
 
 /* ============================ UpdateColorsSDL () ========================= */
diff -u --new-file --recursive tuxnes-0.75-sdl/w.c tuxnes-0.75-codeshare/w.c
--- tuxnes-0.75-sdl/w.c	Wed Apr 11 23:45:48 2001
+++ tuxnes-0.75-codeshare/w.c	Sun Mar 24 17:31:04 2002
@@ -20,8 +20,6 @@
 
 #include <sys/stat.h>
 #include <sys/types.h>
-#include <sys/time.h>
-#include <dirent.h>
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -606,7 +604,6 @@
 {
   int x;
   rgb_t color;
-  struct timeval time;
 
   if (magstep < 1) {
     magstep = 1;
@@ -930,8 +927,7 @@
     scanlines = old_scanlines;
   }
   w_flush ();
-  gettimeofday (&time, NULL);
-  renderer_data.basetime = time.tv_sec;
+  set_renderer_basetime();
   return 0;
 }
 
@@ -1029,31 +1025,13 @@
 void
 UpdateDisplayW(void)
 {
-  struct timeval time;
   unsigned static int frame;
   unsigned int timeframe;
   static int nodisplay = 0;
 
   /* do audio update */
   UpdateAudio();
-
-  /* Check the time.  If we're getting behind, skip a frame to stay in sync. */
-  gettimeofday (&time, NULL);
-  timeframe = (time.tv_sec - renderer_data.basetime) * 50 + time.tv_usec / 20000;     /* PAL */
-  timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;     /* NTSC */
-  frame++;
-  if (halfspeed)
-    timeframe >>= 1;
-  if (doublespeed == 2)
-    timeframe <<= 1;
-  else if (doublespeed > 2)
-    timeframe *= doublespeed;
-  if (desync)
-    frame = timeframe;
-  desync = 0;
-  if (frame < timeframe - 20 && frame % 20 == 0)
-    desync = 1;                 /* If we're more than 20 frames behind, might as well stop counting. */
-
+  set_timeframe(&frame, &timeframe, &desync);
   if (! nodisplay)
     {
       drawimage (PBL);
@@ -1071,13 +1049,7 @@
   needsredraw = 0;
   redrawbackground = 0;
   redrawall = 0;
-
-  /* Slow down if we're getting ahead */
-  if (frame > timeframe + 1 && frameskip == 0)
-    {
-      usleep (16666 * (frame - timeframe - 1));
-    }
-
+  resynchronize(frame, timeframe, frameskip);
   /* Input loop */
   do {
     WEVENT *ev;
@@ -1142,20 +1114,7 @@
 	}
     }
   } while (renderer_data.pause_display);
-  
-  /* Check the time.  If we're getting behind, skip next frame to stay in sync. */
-  gettimeofday (&time, NULL);
-  timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;     /* NTSC */
-  if (halfspeed)
-    timeframe >>= 1;
-  if (doublespeed == 2)
-    timeframe <<= 1;
-  else if (doublespeed > 2)
-    timeframe *= doublespeed;
-  if (frame >= timeframe || frame % 20 == 0)
-    frameskip = 0;
-  else
-    frameskip = 1;
+  set_frameskip (frame, &timeframe, &frameskip);  
 }
 
 #endif
diff -u --new-file --recursive tuxnes-0.75-sdl/x11.c tuxnes-0.75-codeshare/x11.c
--- tuxnes-0.75-sdl/x11.c	Wed Apr 11 23:45:48 2001
+++ tuxnes-0.75-codeshare/x11.c	Sun Mar 24 17:31:27 2002
@@ -20,15 +20,14 @@
 
 #include <sys/stat.h>
 #include <sys/types.h>
-#include <sys/time.h>
 #include <sys/wait.h>
-#include <dirent.h>
 #include <errno.h>
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <renderer_util.h>
 #if defined(__FreeBSD__)
 #include <machine/endian.h>
 #elif defined(__NetBSD__) || defined(__OpenBSD__)
@@ -181,7 +180,6 @@
 void	fbinit(void);
 void	quit(void);
 void	START(void);
-static void	InitScreenshotX11(void);
 static void	SaveScreenshotX11(void);
 static void	DiffUpdateOldX11(void);
 static void	DoBackgroundOldX11(void);
@@ -258,71 +256,11 @@
 #endif
 
 void
-InitScreenshotX11(void)
-{
-  DIR			*dir;
-  struct		dirent *dirp;
-  int			currentnumber = 0;
-
-  /* Allocate space for (tuxnesdir) + (basefilename-snap-xxxx.xpm) + ('\0') */
-  if ((screenshotfile = (char *) malloc (strlen (tuxnesdir) +
-    strlen (basefilename) + 1 + 4 + 1 + 4 + 1 + 3 + 1)) == NULL)
-    {
-      perror ("malloc");
-      exit (1);
-    }
-  sprintf(screenshotfile, "%s-snap-", basefilename);
-
-  /* open the screenshot directory */
-  if ((dir = opendir (tuxnesdir)) == NULL)
-    {
-      return;
-    }
-
-  /* iterate through the files and establish the starting screenshot number */
-  while ((dirp = readdir (dir)) != NULL)
-    {
-      if ((strlen(dirp->d_name) >= 8)
-          && (strncmp (dirp->d_name, screenshotfile, strlen (screenshotfile)) == 0)
-          && (strncmp (dirp->d_name + strlen (dirp->d_name) - 4, ".xpm",
-            strlen (".xpm")) == 0))
-        {
-          dirp->d_name[strlen (dirp->d_name) - 4] = '\0';
-          if ((currentnumber = atoi (dirp->d_name + strlen (screenshotfile))) >
-            screenshotnumber)
-            {
-              screenshotnumber = currentnumber;
-            }
-        }
-    }
-
-  if (++screenshotnumber > 9999)
-    {
-      screenshotnumber = 0;
-    }
-
-  closedir (dir);
-}
-
-void
 SaveScreenshotX11(void)
 {
   int status;
 
-  /* make sure we don't over-write screenshots written by a concurrent TuxNES process */
-  {
-    struct stat buf[1];
-
-    do
-      sprintf (screenshotfile, "%s%s-snap-%04u.xpm", tuxnesdir, basefilename,
-        screenshotnumber ++);
-    while ((! stat (screenshotfile, buf)) && ! (screenshotnumber > 9999));
-  }
-
-  if (screenshotnumber > 9999)
-    {
-      screenshotnumber = 0;
-    }
+  screenshot_check_filename (".xpm", screenshotfile, &screenshotnumber);
 #ifdef HAVE_XPM
   if (renderer->_flags & RENDERER_OLD)
     {
@@ -394,7 +332,6 @@
   int x, y;
   int geometry_mask;
   int border;
-  struct timeval time;
   char *wname[] = {
     PRETTY_NAME,
     PACKAGE
@@ -709,8 +646,7 @@
   for (y = 0; y < tilecachedepth; y++)
     for (x = 0; x < 256; x++)
       tiledirty[y][x] = 1;
-  gettimeofday (&time, NULL);
-  renderer_data.basetime = time.tv_sec;
+  set_renderer_basetime();
   layout =
     XCreatePixmap (display, w, 256 * magstep, 240 * magstep, depth);
 #ifdef HAVE_SHM
@@ -837,7 +773,7 @@
   XFillRectangle (display, w,
 		  blackgc, 0, 0,
 		  width, height);
-  InitScreenshotX11 ();
+  screenshot_init(".xpm", &screenshotfile, &screenshotnumber);
   fbinit ();
   return 0;
 }
@@ -1405,7 +1341,6 @@
 UpdateDisplayX11(void)
 {
   static XEvent ev;
-  struct timeval time;
   unsigned static int frame;
   unsigned int timeframe;
   static int sleep = 0;         /* Initially we start with the emulation running.  If you want to wait until the window receives input focus, change this. */
@@ -1413,24 +1348,7 @@
 
   /* do audio update */
   UpdateAudio();
-
-  /* Check the time.  If we're getting behind, skip a frame to stay in sync. */
-  gettimeofday (&time, NULL);
-  timeframe = (time.tv_sec - renderer_data.basetime) * 50 + time.tv_usec / 20000;     /* PAL */
-  timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;     /* NTSC */
-  frame++;
-  if (halfspeed)
-    timeframe >>= 1;
-  if (doublespeed == 2)
-    timeframe <<= 1;
-  else if (doublespeed > 2)
-    timeframe *= doublespeed;
-  if (desync)
-    frame = timeframe;
-  desync = 0;
-  if (frame < timeframe - 20 && frame % 20 == 0)
-    desync = 1;                 /* If we're more than 20 frames behind, might as well stop counting. */
-
+  set_timeframe(&frame, &timeframe, &desync);
   if (! nodisplay)
     {
       drawimage (PBL);
@@ -1579,13 +1497,7 @@
 	  redrawall = needsredraw = 0;
 	}
     }
-
-  /* Slow down if we're getting ahead */
-  if (frame > timeframe + 1 && frameskip == 0)
-    {
-      usleep (16666 * (frame - timeframe - 1));
-    }
-
+  resynchronize(frame, timeframe, frameskip);
   /* Input loop */
   do {
     /* Handle joystick input */
@@ -1694,20 +1606,7 @@
   needsredraw = 0;
   redrawbackground = 0;
   redrawall = 0;
-
-  /* Check the time.  If we're getting behind, skip next frame to stay in sync. */
-  gettimeofday (&time, NULL);
-  timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;     /* NTSC */
-  if (halfspeed)
-    timeframe >>= 1;
-  if (doublespeed == 2)
-    timeframe <<= 1;
-  else if (doublespeed > 2)
-    timeframe *= doublespeed;
-  if (frame >= timeframe || frame % 20 == 0)
-    frameskip = 0;
-  else
-    frameskip = 1;
+  set_frameskip (frame, &timeframe, &frameskip);
 }
 
 /*
@@ -1729,7 +1628,6 @@
 UpdateDisplayOldX11(void)
 {
   static XEvent ev;
-  struct timeval time;
   unsigned static int frame;
   unsigned int timeframe;
   static int sleep = 0;         /* Initially we start with the emulation running.  If you want to wait until the window receives input focus, change this. */
@@ -1737,24 +1635,7 @@
 
   /* do audio update */
   UpdateAudio();
-
-  /* Check the time.  If we're getting behind, skip a frame to stay in sync. */
-  gettimeofday (&time, NULL);
-  timeframe = (time.tv_sec - renderer_data.basetime) * 50 + time.tv_usec / 20000;     /* PAL */
-  timeframe = (time.tv_sec - renderer_data.basetime) * 60 + time.tv_usec / 16666;     /* NTSC */
-  frame++;
-  if (halfspeed)
-    timeframe >>= 1;
-  if (doublespeed == 2)
-    timeframe <<= 1;
-  else if (doublespeed > 2)
-    timeframe *= doublespeed;
-  if (desync)
-    frame = timeframe;
-  desync = 0;
-  if (frame < timeframe - 20 && frame % 20 == 0)
-    desync = 1;                 /* If we're more than 20 frames behind, might as well stop counting. */
-
+  set_timeframe(&frame, &timeframe, &desync);
   if (! nodisplay)
     {
       if (frame >= timeframe || frame % 20 == 0)
@@ -1773,13 +1654,7 @@
 	    DrawSpritesOldX11();
 	}
     }
-
-  /* Slow down if we're getting ahead */
-  if (frame > timeframe + 1)
-    {
-      usleep (16666 * (frame - timeframe - 1));
-    }
-
+  resynchronize(frame, timeframe, frameskip);
   /* Input loop */
   do {
     /* Handle joystick input */

================================================================================

-- 
Mike

:wq