Added new option -snapname which lets you provide a template for how snapshot

names are generated.

Added new astring functions astring_del, astring_replace, and astring_replacec
to help perform simple search/replace substitution.

docs/config.txt

@@ -453,6 +453,20 @@ Core state/playback options
 	(.cfg), NVRAM (.nv), and memory card files deleted. The default is
 	NULL (no recording).
 
+-snapname <name>
+
+	Describes how MAME should name files for snapshots. <name> is a string
+	that provides a template that is used to generate a filename. Three
+	simple substitutions are provided: the / character represents the
+	path separator on any target platform (even Windows); the string %g
+	represents the driver name of the current game; and the string %i
+	represents an incrementing index. If %i is omitted, then each
+	snapshot taken will overwrite the previous one; otherwise, MAME will
+	find the next empty value for %i and use that for a filename. The
+	default is %g/%i, which creates a separate folder for each game,
+	and names the snapshots under it starting with 0000 and increasing
+	from there.
+
 -mngwrite <filename>
 
 	Writes each video frame to the given <filename> in MNG format,

src/emu/emuopts.c

@@ -64,6 +64,7 @@ const options_entry mame_core_options[] =
 	{ "autosave",                    "0",         OPTION_BOOLEAN,    "enable automatic restore at startup, and automatic save at exit time" },
 	{ "playback;pb",                 NULL,        0,                 "playback an input file" },
 	{ "record;rec",                  NULL,        0,                 "record an input file" },
+	{ "snapname",                    "%g/%i",     0,                 "override of the default snapshot naming; %g == gamename, %i == index" },
 	{ "mngwrite",                    NULL,        0,                 "optional filename to write a MNG movie of the current session" },
 	{ "aviwrite",                    NULL,        0,                 "optional filename to write an AVI movie of the current session" },
 	{ "wavwrite",                    NULL,        0,                 "optional filename to write a WAV file of the current session" },

src/emu/emuopts.h

@@ -63,6 +63,7 @@
 #define OPTION_AUTOSAVE				"autosave"
 #define OPTION_PLAYBACK				"playback"
 #define OPTION_RECORD				"record"
+#define OPTION_SNAPNAME				"snapname"
 #define OPTION_MNGWRITE				"mngwrite"
 #define OPTION_AVIWRITE				"aviwrite"
 #define OPTION_WAVWRITE				"wavwrite"

src/emu/video.c

@@ -2214,28 +2214,63 @@ static void create_snapshot_bitmap(const device_config *screen)
 
 static file_error mame_fopen_next(running_machine *machine, const char *pathoption, const char *extension, mame_file **file)
 {
+	const char *snapname = options_get_string(mame_options(), OPTION_SNAPNAME);
+	astring *snapstr = astring_alloc();
+	astring *fname = astring_alloc();
 	file_error filerr;
-	char *fname;
-	int seq;
-
-	/* allocate temp space for the name */
-	fname = malloc_or_die(strlen(machine->basename) + 1 + 10 + strlen(extension) + 1);
-
-	/* try until we succeed */
-	for (seq = 0; ; seq++)
+	int index;
+	
+	/* handle defaults */
+	if (snapname == NULL || snapname[0] == 0)
+		snapname = "%g/%i";
+	astring_cpyc(snapstr, snapname);
+	
+	/* strip any extension in the provided name and add our own */
+	index = astring_rchr(snapstr, 0, '.');
+	if (index != -1)
+		astring_substr(snapstr, 0, index);
+	astring_catc(snapstr, ".");
+	astring_catc(snapstr, extension);
+	
+	/* substitute path and gamename up front */
+	astring_replacec(snapstr, 0, "/", PATH_SEPARATOR);
+	astring_replacec(snapstr, 0, "%g", machine->basename);
+	
+	/* determine if the template has an index; if not, we always use the same name */
+	if (astring_findc(snapstr, 0, "%i") == -1)
+		astring_cpy(fname, snapstr);
+	
+	/* otherwise, we scan for the next available filename */
+	else
 	{
-		sprintf(fname, "%s" PATH_SEPARATOR "%04d.%s", machine->basename, seq, extension);
-		filerr = mame_fopen(pathoption, fname, OPEN_FLAG_READ, file);
-		if (filerr != FILERR_NONE)
-			break;
-		mame_fclose(*file);
+		int seq;
+		
+		/* try until we succeed */
+		for (seq = 0; ; seq++)
+		{
+			char seqtext[10];
+			
+			/* make text for the sequence number */
+			sprintf(seqtext, "%04d", seq);
+			
+			/* build up the filename */
+			astring_cpy(fname, snapstr);
+			astring_replacec(fname, 0, "%i", seqtext);
+
+			/* try to open the file; stop when we fail */
+			filerr = mame_fopen(pathoption, astring_c(fname), OPEN_FLAG_READ, file);
+			if (filerr != FILERR_NONE)
+				break;
+			mame_fclose(*file);
+		}
 	}
 
 	/* create the final file */
-    filerr = mame_fopen(pathoption, fname, OPEN_FLAG_WRITE | OPEN_FLAG_CREATE | OPEN_FLAG_CREATE_PATHS, file);
+    filerr = mame_fopen(pathoption, astring_c(fname), OPEN_FLAG_WRITE | OPEN_FLAG_CREATE | OPEN_FLAG_CREATE_PATHS, file);
 
     /* free the name and get out */
-    free(fname);
+    astring_free(fname);
+    astring_free(snapstr);
     return filerr;
 }
 

src/lib/util/astring.c

@@ -290,6 +290,30 @@ astring *astring_substr(astring *str, int start, int count)
 }
 
 
+/*-------------------------------------------------
+    astring_del - delete a substring of
+    ourself, keeping everything else
+-------------------------------------------------*/
+
+astring *astring_del(astring *str, int start, int count)
+{
+	int strlength = strlen(str->text);
+
+	/* ignore attempts to do this on the dummy */
+	if (str == &dummy_astring)
+		return str;
+
+	/* normalize parameters */
+	normalize_substr(&start, &count, strlength);
+
+	/* move the data and NULL-terminate */
+	if (count > 0)
+		memmove(str->text + start, str->text + start + count, strlength - (start + count));
+	str->text[strlength - count] = 0;
+	return str;
+}
+
+
 /*-------------------------------------------------
     astring_printf - printf text into an astring
 -------------------------------------------------*/
@@ -498,6 +522,41 @@ int astring_findc(const astring *str, int start, const char *search)
 }
 
 
+/*-------------------------------------------------
+    astring_replace - search in an astring for 
+    another astring, replacing all instances with 
+    a third and returning the number of matches
+-------------------------------------------------*/
+
+int astring_replace(astring *str, int start, const astring *search, const astring *replace)
+{
+	return astring_replacec(str, start, search->text, replace->text);
+}
+
+
+/*-------------------------------------------------
+    astring_replacec - search in an astring for a 
+    C string, replacing all instances with another 
+    C string and returning the number of matches
+-------------------------------------------------*/
+
+int astring_replacec(astring *str, int start, const char *search, const char *replace)
+{
+	int searchlen = strlen(search);
+	int replacelen = strlen(replace);
+	int matches = 0;
+	int curindex;
+	
+	for (curindex = astring_findc(str, start, search); curindex != -1; curindex = astring_findc(str, curindex + replacelen, search))
+	{
+		matches++;
+		astring_del(str, curindex, searchlen);
+		astring_insc(str, curindex, replace);
+	}
+	return matches;
+}
+
+
 
 /***************************************************************************
     ASTRING UTILITIES

src/lib/util/astring.h

@@ -69,6 +69,9 @@ astring *astring_inssubstr(astring *dst, int insbefore, const astring *src, int
 /* extract a substring of ourself, removing everything else */
 astring *astring_substr(astring *str, int start, int count);
 
+/* delete a substring from ourself, keeping everything else */
+astring *astring_del(astring *str, int start, int count);
+
 /* formatted printf to an astring */
 int astring_printf(astring *dst, const char *format, ...) ATTR_PRINTF(2,3);
 
@@ -118,6 +121,12 @@ int astring_find(const astring *str, int start, const astring *search);
 /* search in an astring for a C string, returning offset or -1 if not found */
 int astring_findc(const astring *str, int start, const char *search);
 
+/* search in an astring for another astring, replacing all instances with a third and returning the number of matches */
+int astring_replace(astring *str, int start, const astring *search, const astring *replace);
+
+/* search in an astring for a C string, replacing all instances with another C string and returning the number of matches */
+int astring_replacec(astring *str, int start, const char *search, const char *replace);
+
 
 
 /* ----- astring utilties ----- */