Type cleanups.

dfilter_macro_apply_recurse() returns either NULL or a pointer to
freshly-allocated memory, so it doesn't return a const pointer.
dfilter_macro_apply() calls dfilter_macro_apply_recurse(), so it doesn't
return a const pointer, either.

In dfilter_compile(), have separate variables for the filter handed in
and the macro-expanded filter, the former being const gchar * and the
latter being gchar *.

Change-Id: I191549bf0ff6c09c1278a98432a907c93d5e0e74
Reviewed-on: https://code.wireshark.org/review/12446
Reviewed-by: Guy Harris <guy@alum.mit.edu>

3 files changed, 10 insertions, 9 deletions

diff --git a/epan/dfilter/dfilter-macro.c b/epan/dfilter/dfilter-macro.c
index 56f84ee317..a971633dbb 100644
--- a/epan/dfilter/dfilter-macro.c
+++ b/epan/dfilter/dfilter-macro.c
@@ -160,7 +160,7 @@ static gchar* dfilter_macro_resolve(gchar* name, gchar** args, gchar** error) {
 }
 
 
-static const gchar* dfilter_macro_apply_recurse(const gchar* text, guint depth, gchar** error) {
+static gchar* dfilter_macro_apply_recurse(const gchar* text, guint depth, gchar** error) {
 	enum { OUTSIDE, STARTING, NAME, ARGS } state = OUTSIDE;
 	GString* out;
 	GString* name = NULL;
@@ -322,11 +322,11 @@ finish:
 		FREE_ALL();
 
 		if (changed) {
-			const gchar* resolved = dfilter_macro_apply_recurse(out->str, depth + 1, error);
+			gchar* resolved = dfilter_macro_apply_recurse(out->str, depth + 1, error);
 			g_string_free(out,TRUE);
 			return resolved;
 		} else {
-			const gchar* out_str = wmem_strdup(NULL, out->str);
+			gchar* out_str = wmem_strdup(NULL, out->str);
 			g_string_free(out,TRUE);
 			return out_str;
 		}
@@ -343,7 +343,7 @@ on_error:
 	}
 }
 
-const gchar* dfilter_macro_apply(const gchar* text, gchar** error) {
+gchar* dfilter_macro_apply(const gchar* text, gchar** error) {
 	return dfilter_macro_apply_recurse(text, 0, error);
 }
 
diff --git a/epan/dfilter/dfilter-macro.h b/epan/dfilter/dfilter-macro.h
index 89622529ab..9516648de2 100644
--- a/epan/dfilter/dfilter-macro.h
+++ b/epan/dfilter/dfilter-macro.h
@@ -42,7 +42,7 @@ typedef struct _dfilter_macro_t {
 } dfilter_macro_t;
 
 /* applies all macros to the given text and returns the resulting string or NULL on failure */
-const gchar* dfilter_macro_apply(const gchar* text, gchar** error);
+gchar* dfilter_macro_apply(const gchar* text, gchar** error);
 
 void dfilter_macro_init(void);
 
diff --git a/epan/dfilter/dfilter.c b/epan/dfilter/dfilter.c
index 030a0efcba..a843bbe936 100644
--- a/epan/dfilter/dfilter.c
+++ b/epan/dfilter/dfilter.c
@@ -210,6 +210,7 @@ dfwork_free(dfwork_t *dfw)
 gboolean
 dfilter_compile(const gchar *text, dfilter_t **dfp, gchar **err_msg)
 {
+	gchar		*expanded_text;
 	int		token;
 	dfilter_t	*dfilter;
 	dfwork_t	*dfw;
@@ -228,7 +229,7 @@ dfilter_compile(const gchar *text, dfilter_t **dfp, gchar **err_msg)
 		return FALSE;
 	}
 
-	if ( !( text = dfilter_macro_apply(text, err_msg) ) ) {
+	if ( !( expanded_text = dfilter_macro_apply(text, err_msg) ) ) {
 		return FALSE;
 	}
 
@@ -240,7 +241,7 @@ dfilter_compile(const gchar *text, dfilter_t **dfp, gchar **err_msg)
 	 */
 	global_dfw = dfw;
 
-	df_scanner_text(text);
+	df_scanner_text(expanded_text);
 
 	deprecated = g_ptr_array_new();
 
@@ -359,7 +360,7 @@ dfilter_compile(const gchar *text, dfilter_t **dfp, gchar **err_msg)
 	/* SUCCESS */
 	global_dfw = NULL;
 	dfwork_free(dfw);
-	wmem_free(NULL, (char*)text);
+	wmem_free(NULL, expanded_text);
 	return TRUE;
 
 FAILURE:
@@ -384,7 +385,7 @@ FAILURE:
 		 * case for any error.
 		 */
 		if (*err_msg == NULL)
-			*err_msg = g_strdup_printf("Unable to parse filter string \"%s\".", text);
+			*err_msg = g_strdup_printf("Unable to parse filter string \"%s\".", expanded_text);
 	}
 	*dfp = NULL;
 	return FALSE;