dfilter: Make error a pointer

Make it easier and more natural to test for errors and hand-over
error results.

29 files changed, 158 insertions, 158 deletions

diff --git a/dftest.c b/dftest.c
index f60f891973..2b12a77fab 100644
--- a/dftest.c
+++ b/dftest.c
@@ -165,15 +165,15 @@ static char *
 expand_filter(const char *text, GTimer *timer)
 {
     char *expanded = NULL;
-    char *err_msg = NULL;
+    df_error_t *err = NULL;
 
     g_timer_start(timer);
-    expanded = dfilter_expand(text, &err_msg);
+    expanded = dfilter_expand(text, &err);
     g_timer_stop(timer);
     elapsed_expand = g_timer_elapsed(timer, NULL);
     if (expanded == NULL) {
-        fprintf(stderr, "Error: %s\n", err_msg);
-        g_free(err_msg);
+        fprintf(stderr, "Error: %s\n", err->msg);
+        df_error_free(&err);
     }
     return expanded;
 }
@@ -205,7 +205,7 @@ compile_filter(const char *text, dfilter_t **dfp, GTimer *timer)
             fprintf(stderr, "  %s\n  ", text);
             putloc(stderr, df_err->loc);
         }
-        dfilter_error_free(df_err);
+        df_error_free(&df_err);
     }
     return ok;
 }
diff --git a/epan/color_filters.c b/epan/color_filters.c
index a1623c1333..5f6eab3a3f 100644
--- a/epan/color_filters.c
+++ b/epan/color_filters.c
@@ -182,7 +182,7 @@ color_filters_set_tmp(guint8 filt_nr, const gchar *filter, gboolean disabled, gc
             tmpfilter = ( (filter==NULL) || (i!=filt_nr) ) ? "frame" : filter;
             if (!dfilter_compile(tmpfilter, &compiled_filter, &df_err)) {
                 *err_msg = ws_strdup_printf( "Could not compile color filter name: \"%s\" text: \"%s\".\n%s", name, filter, df_err->msg);
-                dfilter_error_free(df_err);
+                df_error_free(&df_err);
                 g_free(name);
                 return FALSE;
             } else {
@@ -416,7 +416,7 @@ color_filter_compile_cb(gpointer filter_arg, gpointer err)
     if (!dfilter_compile(colorf->filter_text, &colorf->c_colorfilter, &df_err)) {
         *err_msg = ws_strdup_printf("Could not compile color filter name: \"%s\" text: \"%s\".\n%s",
                       colorf->filter_name, colorf->filter_text, df_err->msg);
-        dfilter_error_free(df_err);
+        df_error_free(&df_err);
         /* this filter was compilable before, so this should never happen */
         /* except if the OK button of the parent window has been clicked */
         /* so don't use ws_assert_not_reached() but check the filters again */
@@ -438,7 +438,7 @@ color_filter_validate_cb(gpointer filter_arg, gpointer err)
     if (!dfilter_compile(colorf->filter_text, &colorf->c_colorfilter, &df_err)) {
         *err_msg = ws_strdup_printf("Disabling color filter name: \"%s\" filter: \"%s\".\n%s",
                       colorf->filter_name, colorf->filter_text, df_err->msg);
-        dfilter_error_free(df_err);
+        df_error_free(&df_err);
 
         /* Disable the color filter in the list of color filters. */
         colorf->disabled = TRUE;
@@ -704,7 +704,7 @@ read_filters_file(const gchar *path, FILE *f, gpointer user_data, color_filter_a
 
             if (!disabled && !dfilter_compile(filter_exp, &temp_dfilter, &df_err)) {
                 report_warning("Disabling color filter: Could not compile \"%s\" in colorfilters file \"%s\".\n%s", name, path, df_err->msg);
-                dfilter_error_free(df_err);
+                df_error_free(&df_err);
 
                 /* skip_end_of_line = TRUE; */
                 disabled = TRUE;
diff --git a/epan/dfilter/dfilter-int.h b/epan/dfilter/dfilter-int.h
index 93af43d0e0..47a3952485 100644
--- a/epan/dfilter/dfilter-int.h
+++ b/epan/dfilter/dfilter-int.h
@@ -46,7 +46,7 @@ typedef struct {
 	stnode_t	*st_root;
 	gboolean	parse_failure;
 	unsigned	field_count;
-	df_error_t	error;
+	df_error_t	*error;
 	GPtrArray	*insns;
 	GHashTable	*loaded_fields;
 	GHashTable	*loaded_raw_fields;
@@ -137,13 +137,4 @@ reference_new(const field_info *finfo, gboolean raw);
 void
 reference_free(df_reference_t *ref);
 
-void dfw_error_init(df_error_t *err);
-
-void dfw_error_clear(df_error_t *err);
-
-void dfw_error_set_msg(df_error_t **errp, const char *fmt, ...)
-G_GNUC_PRINTF(2, 3);
-
-void dfw_error_take(df_error_t **errp, df_error_t *src);
-
 #endif
diff --git a/epan/dfilter/dfilter-macro.c b/epan/dfilter/dfilter-macro.c
index 06e11e2d1d..8d9a78fcef 100644
--- a/epan/dfilter/dfilter-macro.c
+++ b/epan/dfilter/dfilter-macro.c
@@ -10,6 +10,7 @@
 
 #include "config.h"
 #define WS_LOG_DOMAIN LOG_DOMAIN_DFILTER
+#include "dfilter-macro.h"
 
 #ifdef DUMP_DFILTER_MACRO
 #include <stdio.h>
@@ -17,8 +18,6 @@
 #include <string.h>
 
 #include "dfilter-int.h"
-#include "dfilter.h"
-#include "dfilter-macro.h"
 #include <ftypes/ftypes.h>
 #include <epan/uat-int.h>
 #include <epan/proto.h>
@@ -37,7 +36,7 @@ void dump_dfilter_macro_t(const dfilter_macro_t *m, const char *function, const
 #define DUMP_MACRO(m)
 #endif
 
-static gchar* dfilter_macro_resolve(gchar* name, gchar** args, gchar** error) {
+static gchar* dfilter_macro_resolve(gchar* name, gchar** args, df_error_t** error) {
 	GString* text;
 	int argc = 0;
 	dfilter_macro_t* m = NULL;
@@ -56,7 +55,7 @@ static gchar* dfilter_macro_resolve(gchar* name, gchar** args, gchar** error) {
 
 	if (!m) {
 		if (error != NULL)
-			*error = g_strdup_printf("macro '%s' does not exist", name);
+			*error = df_error_new_printf(DF_ERROR_GENERIC, NULL, "macro '%s' does not exist", name);
 		return NULL;
 	}
 
@@ -68,8 +67,9 @@ static gchar* dfilter_macro_resolve(gchar* name, gchar** args, gchar** error) {
 
 	if (argc != m->argc) {
 		if (error != NULL) {
-			*error = ws_strdup_printf("wrong number of arguments for macro '%s', expecting %d instead of %d",
-									  name, m->argc, argc);
+			*error = df_error_new_printf(DF_ERROR_GENERIC, NULL,
+							"wrong number of arguments for macro '%s', expecting %d instead of %d",
+							name, m->argc, argc);
 		}
 		return NULL;
 	}
@@ -132,7 +132,7 @@ static gboolean start_is_field_reference(const char *start)
 	return TRUE;
 }
 
-static gchar* dfilter_macro_apply_recurse(const gchar* text, guint depth, gchar** error) {
+static gchar* dfilter_macro_apply_recurse(const gchar* text, guint depth, df_error_t** error) {
 	enum { OUTSIDE, STARTING, NAME, ARGS } state = OUTSIDE;
 	GString* out;
 	GString* name = NULL;
@@ -144,7 +144,7 @@ static gchar* dfilter_macro_apply_recurse(const gchar* text, guint depth, gchar*
 
 	if ( depth > 31) {
 		if (error != NULL)
-			*error = g_strdup("too much nesting in macros");
+			*error = df_error_new_msg("too much nesting in macros");
 		return NULL;
 	}
 
@@ -238,11 +238,11 @@ static gchar* dfilter_macro_apply_recurse(const gchar* text, guint depth, gchar*
 					state = OUTSIDE;
 				} else if ( c == '\0') {
 					if (error != NULL)
-						*error = g_strdup("end of filter in the middle of a macro expression");
+						*error = df_error_new_msg("end of filter in the middle of a macro expression");
 					goto on_error;
 				} else {
 					if (error != NULL)
-						*error = g_strdup("invalid character in macro name");
+						*error = df_error_new_msg("invalid character in macro name");
 					goto on_error;
 				}
 				break;
@@ -250,7 +250,7 @@ static gchar* dfilter_macro_apply_recurse(const gchar* text, guint depth, gchar*
 				switch(c) {
 					case '\0': {
 						if (error != NULL)
-							*error = g_strdup("end of filter in the middle of a macro expression");
+							*error = df_error_new_msg("end of filter in the middle of a macro expression");
 						goto on_error;
 					} case ';': {
 						g_ptr_array_add(args,g_string_free(arg,FALSE));
@@ -264,7 +264,7 @@ static gchar* dfilter_macro_apply_recurse(const gchar* text, guint depth, gchar*
 							break;
 						} else {
 							if (error != NULL)
-								*error = g_strdup("end of filter in the middle of a macro expression");
+								*error = df_error_new_msg("end of filter in the middle of a macro expression");
 							goto on_error;
 						}
 					} default: {
@@ -316,14 +316,14 @@ on_error:
 		FREE_ALL();
 		if (error != NULL) {
 			if (*error == NULL)
-				*error = g_strdup("unknown error in macro expression");
+				*error = df_error_new_msg("unknown error in macro expression");
 		}
 		g_string_free(out,TRUE);
 		return NULL;
 	}
 }
 
-gchar* dfilter_macro_apply(const gchar* text, gchar** error) {
+gchar* dfilter_macro_apply(const gchar* text, df_error_t** error) {
 	return dfilter_macro_apply_recurse(text, 0, error);
 }
 
diff --git a/epan/dfilter/dfilter-macro.h b/epan/dfilter/dfilter-macro.h
index d5c0c46982..896b02fee5 100644
--- a/epan/dfilter/dfilter-macro.h
+++ b/epan/dfilter/dfilter-macro.h
@@ -11,7 +11,7 @@
 #define _DFILTER_MACRO_H
 
 #include <wireshark.h>
-
+#include "dfilter.h"
 
 #define DFILTER_MACRO_FILENAME "dfilter_macros"
 
@@ -30,7 +30,7 @@ typedef struct _dfilter_macro_t {
 } dfilter_macro_t;
 
 /* applies all macros to the given text and returns the resulting string or NULL on failure */
-gchar* dfilter_macro_apply(const gchar* text, gchar** error);
+gchar* dfilter_macro_apply(const gchar* text, df_error_t** error);
 
 void dfilter_macro_init(void);
 
diff --git a/epan/dfilter/dfilter.c b/epan/dfilter/dfilter.c
index 9c21e66998..a3d2be240c 100644
--- a/epan/dfilter/dfilter.c
+++ b/epan/dfilter/dfilter.c
@@ -44,12 +44,10 @@ dfilter_vfail(dfwork_t *dfw, int code, df_loc_t loc,
 	dfw->parse_failure = TRUE;
 
 	/* If we've already reported one error, don't overwite it */
-	if (dfw->error.code < 0 || dfw->error.msg != NULL)
+	if (dfw->error != NULL)
 		return;
 
-	dfw->error.code = code;
-	dfw->error.msg = ws_strdup_vprintf(format, args);
-	dfw->error.loc = loc;
+	dfw->error = df_error_new_vprintf(code, &loc, format, args);
 }
 
 void
@@ -77,7 +75,8 @@ dfilter_fail_throw(dfwork_t *dfw, int code, df_loc_t loc, const char *format, ..
 void
 dfw_set_error_location(dfwork_t *dfw, df_loc_t loc)
 {
-	dfw->error.loc = loc;
+	ws_assert(dfw->error);
+	dfw->error->loc = loc;
 }
 
 header_field_info *
@@ -211,9 +210,6 @@ dfwork_new(void)
 {
 	dfwork_t *dfw = g_new0(dfwork_t, 1);
 
-	dfw_error_init(&dfw->error);
-	dfw->warnings = NULL;
-
 	dfw->references =
 		g_hash_table_new_full(g_direct_hash, g_direct_equal,
 				NULL, (GDestroyNotify)free_refs_array);
@@ -266,6 +262,9 @@ dfwork_free(dfwork_t *dfw)
 
 	g_free(dfw->expanded_text);
 
+	if (dfw->error)
+		df_error_free(&dfw->error);
+
 	wmem_destroy_allocator(dfw->dfw_scope);
 
 	/*
@@ -349,14 +348,14 @@ add_compile_warning(dfwork_t *dfw, const char *format, ...)
 }
 
 char *
-dfilter_expand(const char *expr, char **err_ret)
+dfilter_expand(const char *expr, df_error_t **err_ret)
 {
 	return dfilter_macro_apply(expr, err_ret);
 }
 
 gboolean
 dfilter_compile_real(const gchar *text, dfilter_t **dfp,
-			df_error_t **errpp, unsigned flags,
+			df_error_t **err_ptr, unsigned flags,
 			const char *caller)
 {
 	int		token;
@@ -375,7 +374,8 @@ dfilter_compile_real(const gchar *text, dfilter_t **dfp,
 		ws_debug("%s() called from %s() with null filter",
 			__func__, caller);
 		/* XXX This BUG happens often. Some callers are ignoring these errors. */
-		dfw_error_set_msg(errpp, "BUG: NULL text pointer passed to dfilter_compile");
+		if (err_ptr)
+			*err_ptr = df_error_new_msg("BUG: NULL text pointer passed to dfilter_compile");
 		return FALSE;
 	}
 	else if (*text == '\0') {
@@ -392,7 +392,7 @@ dfilter_compile_real(const gchar *text, dfilter_t **dfp,
 	dfw->apply_optimization = flags & DF_OPTIMIZE;
 
 	if (flags & DF_EXPAND_MACROS) {
-		dfw->expanded_text = dfilter_macro_apply(text, &dfw->error.msg);
+		dfw->expanded_text = dfilter_macro_apply(text, &dfw->error);
 		if (dfw->expanded_text == NULL) {
 			goto FAILURE;
 		}
@@ -404,7 +404,7 @@ dfilter_compile_real(const gchar *text, dfilter_t **dfp,
 	}
 
 	if (df_yylex_init(&scanner) != 0) {
-		dfw_error_set_msg(errpp, "Can't initialize scanner: %s", g_strerror(errno));
+		dfw->error = df_error_new_printf(DF_ERROR_GENERIC, NULL, "Can't initialize scanner: %s", g_strerror(errno));
 		goto FAILURE;
 	}
 
@@ -551,14 +551,18 @@ dfilter_compile_real(const gchar *text, dfilter_t **dfp,
 
 FAILURE:
 	ws_assert(dfw);
-	if (dfw->error.msg == NULL) {
+	if (dfw->error == NULL || dfw->error->msg == NULL) {
 		/* We require an error message. */
 		ws_critical("Unknown error compiling filter: %s", text);
-		dfw_error_set_msg(errpp, "Unknown error compiling filter: %s", text);
+		if (err_ptr)
+			*err_ptr = df_error_new_printf(DF_ERROR_GENERIC, NULL, "Unknown error compiling filter: %s", text);
 	}
 	else {
-		ws_debug("Compiling filter failed with error: %s.", dfw->error.msg);
-		dfw_error_take(errpp, &dfw->error);
+		ws_debug("Compiling filter failed with error: %s.", dfw->error->msg);
+		if (err_ptr) {
+			*err_ptr = dfw->error;
+			dfw->error = NULL;
+		}
 	}
 
 	dfwork_free(dfw);
@@ -761,61 +765,58 @@ reference_free(df_reference_t *ref)
 	g_free(ref);
 }
 
-void
-dfw_error_init(df_error_t *err) {
-	err->code = 0;
-	err->msg = NULL;
-	err->loc.col_start = -1;
-	err->loc.col_len = 0;
+df_error_t *
+df_error_new(int code,  const char *msg, df_loc_t *loc)
+{
+	df_error_t *err = g_new(df_error_t, 1);
+	err->code = code;
+	err->msg = ws_strdup(msg);
+	if (loc) {
+		err->loc.col_start = loc->col_start;
+		err->loc.col_len = loc->col_len;
+	}
+	else {
+		err->loc.col_start = -1;
+		err->loc.col_len = 0;
+	}
+	return err;
 }
 
-void
-dfw_error_clear(df_error_t *err) {
-	g_free(err->msg);
-	dfw_error_init(err);
+df_error_t *
+df_error_new_vprintf(int code, df_loc_t *loc, const char *fmt, va_list ap)
+{
+	df_error_t *err = g_new(df_error_t, 1);
+	err->code = code;
+	err->msg = ws_strdup_vprintf(fmt, ap);
+	if (loc) {
+		err->loc.col_start = loc->col_start;
+		err->loc.col_len = loc->col_len;
+	}
+	else {
+		err->loc.col_start = -1;
+		err->loc.col_len = 0;
+	}
+	return err;
 }
 
-void
-dfw_error_set_msg(df_error_t **errpp, const char *fmt, ...)
+df_error_t *
+df_error_new_printf(int code, df_loc_t *loc, const char *fmt, ...)
 {
-	if (errpp == NULL) {
-		return;
-	}
 	va_list ap;
-
-	df_error_t *errp = g_new(df_error_t, 1);
-	errp->code = DF_ERROR_GENERIC;
 	va_start(ap, fmt);
-	errp->msg = ws_strdup_vprintf(fmt, ap);
+	df_error_t *err = df_error_new_vprintf(code, loc, fmt, ap);
 	va_end(ap);
-	errp->loc.col_start = -1;
-	errp->loc.col_len = 0;
-	*errpp = errp;
-}
-
-void
-dfw_error_take(df_error_t **errpp, df_error_t *src)
-{
-	if (errpp == NULL) {
-		g_free(src->msg);
-		dfw_error_init(src);
-		return;
-	}
-	df_error_t *errp = g_new(df_error_t, 1);
-	errp->code = src->code;
-	errp->msg = src->msg;
-	errp->loc = src->loc;
-	*errpp = errp;
-	dfw_error_init(src);
+	return err;
 }
 
 void
-dfilter_error_free(df_error_t *errp)
+df_error_free(df_error_t **ep)
 {
-	if (errp == NULL)
+	if (*ep == NULL)
 		return;
-	g_free(errp->msg);
-	g_free(errp);
+	g_free((*ep)->msg);
+	g_free(*ep);
+	*ep = NULL;
 }
 
 /*
diff --git a/epan/dfilter/dfilter.h b/epan/dfilter/dfilter.h
index 12c46e3827..fcb47b059e 100644
--- a/epan/dfilter/dfilter.h
+++ b/epan/dfilter/dfilter.h
@@ -13,18 +13,43 @@
 #include <wireshark.h>
 
 #include "dfilter-loc.h"
+#include <epan/proto.h>
 
 /* Passed back to user */
 typedef struct epan_dfilter dfilter_t;
 
-#include <epan/proto.h>
-
 #ifdef __cplusplus
 extern "C" {
 #endif /* __cplusplus */
 
 struct epan_dissect;
 
+#define DF_ERROR_GENERIC		-1
+#define DF_ERROR_UNEXPECTED_END		-2
+
+typedef struct {
+	int code;
+	char *msg;
+	df_loc_t loc;
+} df_error_t;
+
+df_error_t *
+df_error_new(int code, const char *msg, df_loc_t *loc);
+
+df_error_t *
+df_error_new_printf(int code, df_loc_t *loc, const char *fmt, ...)
+G_GNUC_PRINTF(3, 4);
+
+#define df_error_new_msg(msg) \
+	df_error_new_printf(DF_ERROR_GENERIC, NULL, "%s", msg)
+
+df_error_t *
+df_error_new_vprintf(int code, df_loc_t *loc, const char *fmt, va_list ap);
+
+WS_DLL_PUBLIC
+void
+df_error_free(df_error_t **ep);
+
 /* Module-level initialization */
 void
 dfilter_init(void);
@@ -36,7 +61,18 @@ dfilter_cleanup(void);
 /* Perform macro expansion. */
 WS_DLL_PUBLIC
 char *
-dfilter_expand(const char *expr, char **err_ret);
+dfilter_expand(const char *expr, df_error_t **err_ret);
+
+/* Save textual representation of syntax tree (for debugging purposes). */
+#define DF_SAVE_TREE		(1U << 0)
+/* Perform macro substitution on filter text. */
+#define DF_EXPAND_MACROS	(1U << 1)
+/* Do an optimization pass on the compiled filter. */
+#define DF_OPTIMIZE		(1U << 2)
+/* Enable debug trace for flex. */
+#define DF_DEBUG_FLEX		(1U << 3)
+/* Enable debug trace for lemon. */
+#define DF_DEBUG_LEMON		(1U << 4)
 
 /* Compiles a string to a dfilter_t.
  * On success, sets the dfilter* pointed to by dfp
@@ -52,31 +88,6 @@ dfilter_expand(const char *expr, char **err_ret);
  *
  * Returns TRUE on success, FALSE on failure.
  */
-
-#define DF_ERROR_GENERIC		-1
-#define DF_ERROR_UNEXPECTED_END		-2
-
-typedef struct {
-	int code;
-	char *msg;
-	df_loc_t loc;
-} df_error_t;
-
-WS_DLL_PUBLIC
-void
-dfilter_error_free(df_error_t *);
-
-/* Save textual representation of syntax tree (for debugging purposes). */
-#define DF_SAVE_TREE		(1U << 0)
-/* Perform macro substitution on filter text. */
-#define DF_EXPAND_MACROS	(1U << 1)
-/* Do an optimization pass on the compiled filter. */
-#define DF_OPTIMIZE		(1U << 2)
-/* Enable debug trace for flex. */
-#define DF_DEBUG_FLEX		(1U << 3)
-/* Enable debug trace for lemon. */
-#define DF_DEBUG_LEMON		(1U << 4)
-
 WS_DLL_PUBLIC
 gboolean
 dfilter_compile_real(const gchar *text, dfilter_t **dfp,
diff --git a/epan/dfilter/semcheck.c b/epan/dfilter/semcheck.c
index 8683f96ff3..7944bf4409 100644
--- a/epan/dfilter/semcheck.c
+++ b/epan/dfilter/semcheck.c
@@ -151,9 +151,8 @@ compatible_ftypes(ftenum_t a, ftenum_t b)
 /* Don't set the error message if it's already set. */
 #define SET_ERROR(dfw, str) \
 	do {						\
-		if ((str) != NULL && (dfw)->error.msg == NULL) { \
-			(dfw)->error.msg = str;		\
-			(dfw)->error.code = DF_ERROR_GENERIC;	\
+		if ((str) != NULL && (dfw)->error == NULL) {	\
+			(dfw)->error = df_error_new_msg(str);	\
 		}					\
 		else {					\
 			g_free(str);			\
@@ -181,7 +180,7 @@ dfilter_fvalue_from_literal(dfwork_t *dfw, ftenum_t ftype, stnode_t *st,
 		 * to an item from value_string.
 		 */
 		if (fv) {
-			dfw_error_clear(&dfw->error);
+			df_error_free(&dfw->error);
 		}
 	}
 	if (fv == NULL) {
@@ -212,7 +211,7 @@ dfilter_fvalue_from_string(dfwork_t *dfw, ftenum_t ftype, stnode_t *st,
 		 * to an item from value_string.
 		 */
 		if (fv) {
-			dfw_error_clear(&dfw->error);
+			df_error_free(&dfw->error);
 		}
 	}
 	if (fv == NULL) {
@@ -330,7 +329,7 @@ mk_fvalue_from_val_string(dfwork_t *dfw, header_field_info *hfinfo, const char *
 			 * Prefer this error message to whatever error message
 			 * has already been set.
 			 */
-			dfw_error_clear(&dfw->error);
+			df_error_free(&dfw->error);
 			dfilter_fail(dfw, DF_ERROR_GENERIC, loc, "\"%s\" cannot be found among the possible values for %s.",
 				s, hfinfo->abbrev);
 			return NULL;
@@ -347,7 +346,7 @@ mk_fvalue_from_val_string(dfwork_t *dfw, header_field_info *hfinfo, const char *
 	/* Reset the error message, since *something* interesting will happen,
 	 * and the error message will be more interesting than any error message
 	 * I happen to have now. */
-	dfw_error_clear(&dfw->error);
+	df_error_free(&dfw->error);
 
 	if (hfinfo->display & BASE_RANGE_STRING) {
 		dfilter_fail(dfw, DF_ERROR_GENERIC, loc, "\"%s\" cannot accept [range] strings as values.",
diff --git a/epan/dissectors/packet-ncp2222.inc b/epan/dissectors/packet-ncp2222.inc
index 96c67f4b7d..85445b6e8b 100644
--- a/epan/dissectors/packet-ncp2222.inc
+++ b/epan/dissectors/packet-ncp2222.inc
@@ -7093,7 +7093,7 @@ ncp2222_compile_dfilters(void)
                              &req_conds[i].dfilter, &df_err)) {
             g_error("NCP dissector failed to compile dfilter \"%s\": %s\n",
                       req_conds[i].dfilter_text, df_err->msg);
-            dfilter_error_free(df_err);
+            df_error_free(&df_err);
             ws_assert_not_reached();
         }
     }
diff --git a/epan/tap.c b/epan/tap.c
index da0b378d44..8311de7dc6 100644
--- a/epan/tap.c
+++ b/epan/tap.c
@@ -560,7 +560,7 @@ register_tap_listener(const char *tapname, void *tapdata, const char *fstring,
 			g_string_printf(error_string,
 			    "Filter \"%s\" is invalid - %s",
 			    fstring, df_err->msg);
-			dfilter_error_free(df_err);
+			df_error_free(&df_err);
 			free_tap_listener(tl);
 			return error_string;
 		}
@@ -621,7 +621,7 @@ set_tap_dfilter(void *tapdata, const char *fstring)
 				g_string_printf(error_string,
 						 "Filter \"%s\" is invalid - %s",
 						 fstring, df_err->msg);
-				dfilter_error_free(df_err);
+				df_error_free(&df_err);
 				return error_string;
 			}
 		}
diff --git a/epan/wslua/wslua_field.c b/epan/wslua/wslua_field.c
index b7a409d0eb..1134bc761a 100644
--- a/epan/wslua/wslua_field.c
+++ b/epan/wslua/wslua_field.c
@@ -587,7 +587,7 @@ void lua_prime_all_fields(proto_tree* tree _U_) {
             g_string_free(error,TRUE);
         } else if (!dfilter_compile(fake_tap_filter->str, &wslua_dfilter, &df_err)) {
             report_failure("while compiling dfilter \"%s\" for wslua: %s", fake_tap_filter->str, df_err->msg);
-            dfilter_error_free(df_err);
+            df_error_free(&df_err);
         }
     }
     g_string_free(fake_tap_filter, TRUE);
diff --git a/file.c b/file.c
index 164786c28c..5908929cfe 100644
--- a/file.c
+++ b/file.c
@@ -1501,7 +1501,7 @@ cf_filter_packets(capture_file *cf, gchar *dftext, gboolean force)
                     "See the help for a description of the display filter syntax.",
                     "\"%s\" isn't a valid display filter: %s",
                     dftext, df_err->msg);
-            dfilter_error_free(df_err);
+            df_error_free(&df_err);
             g_free(dftext);
             return CF_ERROR;
         }
diff --git a/packaging/debian/libwireshark0.symbols b/packaging/debian/libwireshark0.symbols
index 9ec29a85a7..6edc35b40a 100644
--- a/packaging/debian/libwireshark0.symbols
+++ b/packaging/debian/libwireshark0.symbols
@@ -279,7 +279,6 @@ libwireshark.so.0 libwireshark0 #MINVER#
  dfilter_compile_real@Base 3.7.0
  dfilter_deprecated_tokens@Base 1.9.1
  dfilter_dump@Base 1.9.1
- dfilter_error_free@Base 4.1.0
  dfilter_expand@Base 3.7.0
  dfilter_free@Base 1.9.1
  dfilter_load_field_references@Base 3.7.0
diff --git a/rawshark.c b/rawshark.c
index 74cfe22cb8..01996e3a78 100644
--- a/rawshark.c
+++ b/rawshark.c
@@ -751,7 +751,7 @@ main(int argc, char *argv[])
         for (i = 0; i < n_rfilters; i++) {
             if (!dfilter_compile(rfilters[i], &rfcodes[n_rfcodes], &df_err)) {
                 cmdarg_err("%s", df_err->msg);
-                dfilter_error_free(df_err);
+                df_error_free(&df_err);
                 ret = INVALID_DFILTER;
                 goto clean_exit;
             }
diff --git a/sharkd_session.c b/sharkd_session.c
index d4e9aa8656..5add951666 100644
--- a/sharkd_session.c
+++ b/sharkd_session.c
@@ -4099,7 +4099,7 @@ sharkd_session_process_check(char *buf, const jsmntok_t *tokens, int count)
                 sharkd_json_simple_ok(rpcid);
 
             dfilter_free(dfp);
-            dfilter_error_free(df_err);
+            df_error_free(&df_err);
             return 0;
         }
         else
@@ -4108,7 +4108,7 @@ sharkd_session_process_check(char *buf, const jsmntok_t *tokens, int count)
                     rpcid, -5001, NULL,
                     "Filter invalid - %s", df_err->msg
                     );
-            dfilter_error_free(df_err);
+            df_error_free(&df_err);
             return -5001;
         }
     }
diff --git a/tfshark.c b/tfshark.c
index ad548a3914..46b0c613a0 100644
--- a/tfshark.c
+++ b/tfshark.c
@@ -861,7 +861,7 @@ main(int argc, char *argv[])
     if (rfilter != NULL) {
         if (!dfilter_compile(rfilter, &rfcode, &df_err)) {
             cmdarg_err("%s", df_err->msg);
-            dfilter_error_free(df_err);
+            df_error_free(&df_err);
             exit_status = WS_EXIT_INVALID_FILTER;
             goto clean_exit;
         }
@@ -871,7 +871,7 @@ main(int argc, char *argv[])
     if (dfilter != NULL) {
         if (!dfilter_compile(dfilter, &dfcode, &df_err)) {
             cmdarg_err("%s", df_err->msg);
-            dfilter_error_free(df_err);
+            df_error_free(&df_err);
             exit_status = WS_EXIT_INVALID_FILTER;
             goto clean_exit;
         }
diff --git a/tshark.c b/tshark.c
index 0dd751f6a1..9022fd3a8a 100644
--- a/tshark.c
+++ b/tshark.c
@@ -640,15 +640,14 @@ static gboolean
 _compile_dfilter(const char *text, dfilter_t **dfp, const char *caller)
 {
     gboolean ok;
-    char *err_msg = NULL;
     df_error_t *df_err;
     char *err_off;
     char *expanded;
 
-    expanded = dfilter_expand(text, &err_msg);
+    expanded = dfilter_expand(text, &df_err);
     if (expanded == NULL) {
-        cmdarg_err("%s", err_msg);
-        g_free(err_msg);
+        cmdarg_err("%s", df_err->msg);
+        df_error_free(&df_err);
         return FALSE;
     }
 
@@ -662,7 +661,7 @@ _compile_dfilter(const char *text, dfilter_t **dfp, const char *caller)
             cmdarg_err_cont("    %s", err_off);
             g_free(err_off);
         }
-        dfilter_error_free(df_err);
+        df_error_free(&df_err);
     }
 
     g_free(expanded);
diff --git a/ui/logray/logray_main.cpp b/ui/logray/logray_main.cpp
index 4a30a8e431..b572d6350f 100644
--- a/ui/logray/logray_main.cpp
+++ b/ui/logray/logray_main.cpp
@@ -962,7 +962,7 @@ int main(int argc, char *qt_argv[])
                                          QObject::tr("The filter expression %1 isn't a valid display filter. (%2).")
                                                  .arg(global_commandline_info.jfilter, df_err->msg),
                                          QMessageBox::Ok);
-                    dfilter_error_free(df_err);
+                    df_error_free(&df_err);
                 } else {
                     /* Filter ok, jump to the first packet matching the filter
                        conditions. Default search direction is forward, but if
diff --git a/ui/logray/logray_main_window.cpp b/ui/logray/logray_main_window.cpp
index 4574df7313..0d7d5aa100 100644
--- a/ui/logray/logray_main_window.cpp
+++ b/ui/logray/logray_main_window.cpp
@@ -1178,7 +1178,7 @@ void LograyMainWindow::mergeCaptureFile()
                 QMessageBox::warning(this, tr("Invalid Read Filter"),
                                      QString(tr("The filter expression %1 isn't a valid read filter. (%2).").arg(read_filter, df_err->msg)),
                                      QMessageBox::Ok);
-                dfilter_error_free(df_err);
+                df_error_free(&df_err);
                 continue;
             }
         } else {
diff --git a/ui/logray/logray_main_window_slots.cpp b/ui/logray/logray_main_window_slots.cpp
index 89ec698206..b734cfd2d8 100644
--- a/ui/logray/logray_main_window_slots.cpp
+++ b/ui/logray/logray_main_window_slots.cpp
@@ -206,7 +206,7 @@ bool LograyMainWindow::openCaptureFile(QString cf_path, QString read_filter, uns
                     QString(" isn't a valid display filter. (") +
                     df_err->msg + QString(")."),
                     QMessageBox::Ok);
-            dfilter_error_free(df_err);
+            df_error_free(&df_err);
 
             if (!name_param) {
                 // go back to the selection dialogue only if the file
diff --git a/ui/qt/coloring_rules_dialog.cpp b/ui/qt/coloring_rules_dialog.cpp
index df178ec101..d1ff0d5827 100644
--- a/ui/qt/coloring_rules_dialog.cpp
+++ b/ui/qt/coloring_rules_dialog.cpp
@@ -164,7 +164,7 @@ bool ColoringRulesDialog::isValidFilter(QString filter, QString * error)
     if (df_err)
     {
         error->append(df_err->msg);
-        dfilter_error_free(df_err);
+        df_error_free(&df_err);
     }
 
     return false;
diff --git a/ui/qt/iax2_analysis_dialog.cpp b/ui/qt/iax2_analysis_dialog.cpp
index 70d65f8b13..bd9a534a07 100644
--- a/ui/qt/iax2_analysis_dialog.cpp
+++ b/ui/qt/iax2_analysis_dialog.cpp
@@ -299,7 +299,7 @@ Iax2AnalysisDialog::Iax2AnalysisDialog(QWidget &parent, CaptureFile &cf) :
     /* Try to compile the filter. */
     if (!dfilter_compile(filter_text, &sfcode, &df_err)) {
         err_str_ = QString(df_err->msg);
-        dfilter_error_free(df_err);
+        df_error_free(&df_err);
         updateWidgets();
         return;
     }
diff --git a/ui/qt/io_graph_dialog.cpp b/ui/qt/io_graph_dialog.cpp
index 51b50a2f79..c2c6f3b628 100644
--- a/ui/qt/io_graph_dialog.cpp
+++ b/ui/qt/io_graph_dialog.cpp
@@ -1729,7 +1729,7 @@ void IOGraph::setFilter(const QString &filter)
         dfilter_free(dfilter);
         if (!status) {
             config_err_ = QString::fromUtf8(df_err->msg);
-            dfilter_error_free(df_err);
+            df_error_free(&df_err);
             filter_ = full_filter;
             return;
         }
diff --git a/ui/qt/main.cpp b/ui/qt/main.cpp
index b52635fb08..f74d33a1de 100644
--- a/ui/qt/main.cpp
+++ b/ui/qt/main.cpp
@@ -991,7 +991,7 @@ int main(int argc, char *qt_argv[])
                                          QObject::tr("The filter expression %1 isn't a valid display filter. (%2).")
                                                  .arg(global_commandline_info.jfilter, df_err->msg),
                                          QMessageBox::Ok);
-                    dfilter_error_free(df_err);
+                    df_error_free(&df_err);
                 } else {
                     /* Filter ok, jump to the first packet matching the filter
                        conditions. Default search direction is forward, but if
diff --git a/ui/qt/widgets/display_filter_edit.cpp b/ui/qt/widgets/display_filter_edit.cpp
index bd11f328fa..3748046498 100644
--- a/ui/qt/widgets/display_filter_edit.cpp
+++ b/ui/qt/widgets/display_filter_edit.cpp
@@ -541,7 +541,7 @@ void DisplayFilterEdit::buildCompletionList(const QString &field_word, const QSt
             autocomplete_accepts_field_ = false;
         }
         dfilter_free(test_df);
-        dfilter_error_free(df_err);
+        df_error_free(&df_err);
         filter_word_preamble_ = preamble;
     }
 
diff --git a/ui/qt/widgets/syntax_line_edit.cpp b/ui/qt/widgets/syntax_line_edit.cpp
index 69afe225f0..78cb7283e9 100644
--- a/ui/qt/widgets/syntax_line_edit.cpp
+++ b/ui/qt/widgets/syntax_line_edit.cpp
@@ -238,7 +238,7 @@ bool SyntaxLineEdit::checkDisplayFilter(QString filter)
         setSyntaxState(SyntaxLineEdit::Invalid);
         syntax_error_message_ = QString::fromUtf8(df_err->msg);
         syntax_error_message_full_ = createSyntaxErrorMessageFull(filter, syntax_error_message_, df_err->loc.col_start, df_err->loc.col_len);
-        dfilter_error_free(df_err);
+        df_error_free(&df_err);
     }
     dfilter_free(dfp);
 
diff --git a/ui/qt/wireshark_main_window.cpp b/ui/qt/wireshark_main_window.cpp
index db1d56e0dd..39766c5d58 100644
--- a/ui/qt/wireshark_main_window.cpp
+++ b/ui/qt/wireshark_main_window.cpp
@@ -1218,7 +1218,7 @@ void WiresharkMainWindow::mergeCaptureFile()
                 QMessageBox::warning(this, tr("Invalid Read Filter"),
                                      QString(tr("The filter expression %1 isn't a valid read filter. (%2).").arg(read_filter, df_err->msg)),
                                      QMessageBox::Ok);
-                dfilter_error_free(df_err);
+                df_error_free(&df_err);
                 continue;
             }
         } else {
@@ -3053,7 +3053,7 @@ QString WiresharkMainWindow::findRtpStreams(QVector<rtpstream_id_t *> *stream_id
     /* Try to compile the filter. */
     if (!dfilter_compile(filter_text, &sfcode, &df_err)) {
         QString err = QString(df_err->msg);
-        dfilter_error_free(df_err);
+        df_error_free(&df_err);
         return err;
     }
 
diff --git a/ui/qt/wireshark_main_window_slots.cpp b/ui/qt/wireshark_main_window_slots.cpp
index 129739c1c1..523355876c 100644
--- a/ui/qt/wireshark_main_window_slots.cpp
+++ b/ui/qt/wireshark_main_window_slots.cpp
@@ -234,7 +234,7 @@ bool WiresharkMainWindow::openCaptureFile(QString cf_path, QString read_filter,
                     QString(" isn't a valid display filter. (") +
                     df_err->msg + QString(")."),
                     QMessageBox::Ok);
-            dfilter_error_free(df_err);
+            df_error_free(&df_err);
             if (!name_param) {
                 // go back to the selection dialogue only if the file
                 // was selected from this dialogue
diff --git a/ui/tap-tcp-stream.c b/ui/tap-tcp-stream.c
index 4440606fed..2f96441a83 100644
--- a/ui/tap-tcp-stream.c
+++ b/ui/tap-tcp-stream.c
@@ -267,7 +267,7 @@ select_tcpip_session(capture_file *cf)
     /* no real filter yet */
     if (!dfilter_compile("tcp", &sfcode, &df_err)) {
         simple_dialog(ESD_TYPE_ERROR, ESD_BTN_OK, "%s", df_err->msg);
-        dfilter_error_free(df_err);
+        df_error_free(&df_err);
         return G_MAXUINT32;
     }