diff.c: return pattern entry pointer rather than just the hunk header pattern

This is in preparation for associating a flag with each pattern which will
control how the pattern is interpreted. For example, as a basic or extended
regular expression.

Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff.c

@@ -94,32 +94,35 @@ static int parse_lldiff_command(const char *var, const char *ep, const char *val
  * to define a customized regexp to find the beginning of a function to
  * be used for hunk header lines of "diff -p" style output.
  */
-static struct funcname_pattern {
+struct funcname_pattern_entry {
 	char *name;
 	char *pattern;
-	struct funcname_pattern *next;
+};
+static struct funcname_pattern_list {
+	struct funcname_pattern_list *next;
+	struct funcname_pattern_entry e;
 } *funcname_pattern_list;
 
 static int parse_funcname_pattern(const char *var, const char *ep, const char *value)
 {
 	const char *name;
 	int namelen;
-	struct funcname_pattern *pp;
+	struct funcname_pattern_list *pp;
 
 	name = var + 5; /* "diff." */
 	namelen = ep - name;
 
 	for (pp = funcname_pattern_list; pp; pp = pp->next)
-		if (!strncmp(pp->name, name, namelen) && !pp->name[namelen])
+		if (!strncmp(pp->e.name, name, namelen) && !pp->e.name[namelen])
 			break;
 	if (!pp) {
 		pp = xcalloc(1, sizeof(*pp));
-		pp->name = xmemdupz(name, namelen);
+		pp->e.name = xmemdupz(name, namelen);
 		pp->next = funcname_pattern_list;
 		funcname_pattern_list = pp;
 	}
-	free(pp->pattern);
-	pp->pattern = xstrdup(value);
+	free(pp->e.pattern);
+	pp->e.pattern = xstrdup(value);
 	return 0;
 }
 
@@ -1377,20 +1380,17 @@ int diff_filespec_is_binary(struct diff_filespec *one)
 	return one->is_binary;
 }
 
-static const char *funcname_pattern(const char *ident)
+static const struct funcname_pattern_entry *funcname_pattern(const char *ident)
 {
-	struct funcname_pattern *pp;
+	struct funcname_pattern_list *pp;
 
 	for (pp = funcname_pattern_list; pp; pp = pp->next)
-		if (!strcmp(ident, pp->name))
-			return pp->pattern;
+		if (!strcmp(ident, pp->e.name))
+			return &pp->e;
 	return NULL;
 }
 
-static struct builtin_funcname_pattern {
-	const char *name;
-	const char *pattern;
-} builtin_funcname_pattern[] = {
+static const struct funcname_pattern_entry builtin_funcname_pattern[] = {
 	{ "java", "!^[ 	]*\\(catch\\|do\\|for\\|if\\|instanceof\\|"
 			"new\\|return\\|switch\\|throw\\|while\\)\n"
 			"^[ 	]*\\(\\([ 	]*"
@@ -1407,9 +1407,10 @@ static struct builtin_funcname_pattern {
 	{ "ruby", "^\\s*\\(\\(class\\|module\\|def\\)\\s.*\\)$" },
 };
 
-static const char *diff_funcname_pattern(struct diff_filespec *one)
+static const struct funcname_pattern_entry *diff_funcname_pattern(struct diff_filespec *one)
 {
-	const char *ident, *pattern;
+	const char *ident;
+	const struct funcname_pattern_entry *pe;
 	int i;
 
 	diff_filespec_check_attr(one);
@@ -1424,9 +1425,9 @@ static const char *diff_funcname_pattern(struct diff_filespec *one)
 		return funcname_pattern("default");
 
 	/* Look up custom "funcname.$ident" regexp from config. */
-	pattern = funcname_pattern(ident);
-	if (pattern)
-		return pattern;
+	pe = funcname_pattern(ident);
+	if (pe)
+		return pe;
 
 	/*
 	 * And define built-in fallback patterns here.  Note that
@@ -1434,7 +1435,7 @@ static const char *diff_funcname_pattern(struct diff_filespec *one)
 	 */
 	for (i = 0; i < ARRAY_SIZE(builtin_funcname_pattern); i++)
 		if (!strcmp(ident, builtin_funcname_pattern[i].name))
-			return builtin_funcname_pattern[i].pattern;
+			return &builtin_funcname_pattern[i];
 
 	return NULL;
 }
@@ -1512,11 +1513,11 @@ static void builtin_diff(const char *name_a,
 		xdemitconf_t xecfg;
 		xdemitcb_t ecb;
 		struct emit_callback ecbdata;
-		const char *funcname_pattern;
+		const struct funcname_pattern_entry *pe;
 
-		funcname_pattern = diff_funcname_pattern(one);
-		if (!funcname_pattern)
-			funcname_pattern = diff_funcname_pattern(two);
+		pe = diff_funcname_pattern(one);
+		if (!pe)
+			pe = diff_funcname_pattern(two);
 
 		memset(&xecfg, 0, sizeof(xecfg));
 		memset(&ecbdata, 0, sizeof(ecbdata));
@@ -1528,8 +1529,8 @@ static void builtin_diff(const char *name_a,
 		xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
 		xecfg.ctxlen = o->context;
 		xecfg.flags = XDL_EMIT_FUNCNAMES;
-		if (funcname_pattern)
-			xdiff_set_find_func(&xecfg, funcname_pattern);
+		if (pe)
+			xdiff_set_find_func(&xecfg, pe->pattern);
 		if (!diffopts)
 			;
 		else if (!prefixcmp(diffopts, "--unified="))