dfilter: Improve syntax error message

Pass simple token value and use it for the error message. This string
is freed in the parser destructor.

3 files changed, 71 insertions, 78 deletions

diff --git a/epan/dfilter/grammar.lemon b/epan/dfilter/grammar.lemon
index 66158129be..1d7d4e73db 100644
--- a/epan/dfilter/grammar.lemon
+++ b/epan/dfilter/grammar.lemon
@@ -79,7 +79,10 @@ any "error" symbols are shifted, if possible. */
 
 	switch(stnode_type_id(TOKEN)) {
 		case STTYPE_UNINITIALIZED:
-			dfilter_fail(dfw, "Syntax error.");
+			if ((TOKEN)->token_value != NULL)
+				dfilter_fail(dfw, "Syntax error near \"%s\".", stnode_token_value(TOKEN));
+			else
+				dfilter_fail(dfw, "Syntax error.");
 			break;
 		case STTYPE_TEST:
 			dfilter_fail(dfw, "Syntax error, TEST.");
diff --git a/epan/dfilter/scanner.l b/epan/dfilter/scanner.l
index 0ff0d906be..77870c5fa3 100644
--- a/epan/dfilter/scanner.l
+++ b/epan/dfilter/scanner.l
@@ -88,7 +88,8 @@ static int set_lval_str(int token, const char *token_value);
 static int set_lval_field(int token, header_field_info *hfinfo, const char *token_value);
 static int set_lval_func(int token, df_func_def_t *func, const char *token_value);
 static int set_lval_int(dfwork_t *dfw, int token, const char *token_value);
-static int simple(int token);
+static int simple(int token, const char *token_value);
+#define SIMPLE(token) simple(token, yytext)
 static gboolean str_to_gint32(dfwork_t *dfw, const char *s, gint32* pint);
 
 /*
@@ -117,61 +118,61 @@ static gboolean str_to_gint32(dfwork_t *dfw, const char *s, gint32* pint);
 	 * should have used commas from the beginning, but now we are stuck with
 	 * whitespace as separators. */
 	if (yyextra->in_set) {
-		return simple(TOKEN_WHITESPACE);
+		return simple(TOKEN_WHITESPACE, NULL);
 	}
 }
 
 
 
-"("				return simple(TOKEN_LPAREN);
-")"				return simple(TOKEN_RPAREN);
-","				return simple(TOKEN_COMMA);
+"("		return SIMPLE(TOKEN_LPAREN);
+")"		return SIMPLE(TOKEN_RPAREN);
+","		return SIMPLE(TOKEN_COMMA);
 
 "{"[[:blank:]\n]*	{
 	yyextra->in_set = TRUE;
-	return simple(TOKEN_LBRACE);
+	return simple(TOKEN_LBRACE, "{");
 }
-[[:blank:]\n]*".."[[:blank:]\n]*	return simple(TOKEN_DOTDOT);
+[[:blank:]\n]*".."[[:blank:]\n]*	return simple(TOKEN_DOTDOT, "..");
 [[:blank:]\n]*"}"	{
 	yyextra->in_set = FALSE;
-	return simple(TOKEN_RBRACE);
+	return simple(TOKEN_RBRACE, "}");
 }
 
-"=="			return simple(TOKEN_TEST_EQ);
-"eq"			return simple(TOKEN_TEST_EQ);
+"=="		return SIMPLE(TOKEN_TEST_EQ);
+"eq"		return SIMPLE(TOKEN_TEST_EQ);
 "!="			{
 	add_deprecated_token(yyextra->deprecated, "!=");
-	return simple(TOKEN_TEST_NE);
+	return SIMPLE(TOKEN_TEST_NE);
 }
 "ne"			{
 	add_deprecated_token(yyextra->deprecated, "ne");
-	return simple(TOKEN_TEST_NE);
-}
-">"				return simple(TOKEN_TEST_GT);
-"gt"			return simple(TOKEN_TEST_GT);
-">="			return simple(TOKEN_TEST_GE);
-"ge"			return simple(TOKEN_TEST_GE);
-"<"				return simple(TOKEN_TEST_LT);
-"lt"			return simple(TOKEN_TEST_LT);
-"<="			return simple(TOKEN_TEST_LE);
-"le"			return simple(TOKEN_TEST_LE);
-"bitwise_and"	return simple(TOKEN_TEST_BITWISE_AND);
-"&"				return simple(TOKEN_TEST_BITWISE_AND);
-"contains"		return simple(TOKEN_TEST_CONTAINS);
-"~"				return simple(TOKEN_TEST_MATCHES);
-"matches"		return simple(TOKEN_TEST_MATCHES);
-"!"				return simple(TOKEN_TEST_NOT);
-"not"			return simple(TOKEN_TEST_NOT);
-"&&"			return simple(TOKEN_TEST_AND);
-"and"			return simple(TOKEN_TEST_AND);
-"||"			return simple(TOKEN_TEST_OR);
-"or"			return simple(TOKEN_TEST_OR);
-"in"			return simple(TOKEN_TEST_IN);
+	return SIMPLE(TOKEN_TEST_NE);
+}
+">"		return SIMPLE(TOKEN_TEST_GT);
+"gt"		return SIMPLE(TOKEN_TEST_GT);
+">="		return SIMPLE(TOKEN_TEST_GE);
+"ge"		return SIMPLE(TOKEN_TEST_GE);
+"<"		return SIMPLE(TOKEN_TEST_LT);
+"lt"		return SIMPLE(TOKEN_TEST_LT);
+"<="		return SIMPLE(TOKEN_TEST_LE);
+"le"		return SIMPLE(TOKEN_TEST_LE);
+"bitwise_and"	return SIMPLE(TOKEN_TEST_BITWISE_AND);
+"&"		return SIMPLE(TOKEN_TEST_BITWISE_AND);
+"contains"	return SIMPLE(TOKEN_TEST_CONTAINS);
+"~"		return SIMPLE(TOKEN_TEST_MATCHES);
+"matches"	return SIMPLE(TOKEN_TEST_MATCHES);
+"!"		return SIMPLE(TOKEN_TEST_NOT);
+"not"		return SIMPLE(TOKEN_TEST_NOT);
+"&&"		return SIMPLE(TOKEN_TEST_AND);
+"and"		return SIMPLE(TOKEN_TEST_AND);
+"||"		return SIMPLE(TOKEN_TEST_OR);
+"or"		return SIMPLE(TOKEN_TEST_OR);
+"in"		return SIMPLE(TOKEN_TEST_IN);
 
 
 "["					{
 	BEGIN(RANGE_INT);
-	return simple(TOKEN_LBRACKET);
+	return SIMPLE(TOKEN_LBRACKET);
 }
 
 <RANGE_INT>[+-]?[[:digit:]]+		{
@@ -186,22 +187,22 @@ static gboolean str_to_gint32(dfwork_t *dfw, const char *s, gint32* pint);
 
 <RANGE_INT,RANGE_PUNCT>":"		{
 	BEGIN(RANGE_INT);
-	return simple(TOKEN_COLON);
+	return SIMPLE(TOKEN_COLON);
 }
 
 <RANGE_PUNCT>"-"			{
 	BEGIN(RANGE_INT);
-	return simple(TOKEN_HYPHEN);
+	return SIMPLE(TOKEN_HYPHEN);
 }
 
 <RANGE_INT,RANGE_PUNCT>","		{
 	BEGIN(RANGE_INT);
-	return simple(TOKEN_COMMA);
+	return SIMPLE(TOKEN_COMMA);
 }
 
 <RANGE_INT,RANGE_PUNCT>"]"		{
 	BEGIN(INITIAL);
-	return simple(TOKEN_RBRACKET);
+	return SIMPLE(TOKEN_RBRACKET);
 }
 
 	/* Error if none of the above while scanning a range (slice) */
@@ -444,7 +445,7 @@ static gboolean str_to_gint32(dfwork_t *dfw, const char *s, gint32* pint);
 DIAG_ON_FLEX
 
 static int
-simple(int token)
+simple(int token, const char *token_value)
 {
 	switch (token) {
 		case TOKEN_LPAREN:
@@ -475,6 +476,7 @@ simple(int token)
 		default:
 			ws_assert_not_reached();
 	}
+	stnode_init(df_lval, STTYPE_UNINITIALIZED, NULL, token_value);
 	return token;
 }
 
diff --git a/epan/dfilter/syntax-tree.c b/epan/dfilter/syntax-tree.c
index 047aae25d6..fe6e48bf0c 100644
--- a/epan/dfilter/syntax-tree.c
+++ b/epan/dfilter/syntax-tree.c
@@ -76,15 +76,17 @@ sttype_lookup(sttype_id_t type_id)
 	return result;
 }
 
-
-stnode_t*
-stnode_new(sttype_id_t type_id, gpointer data, const char *token_value)
+void
+stnode_init(stnode_t *node, sttype_id_t type_id, gpointer data,  const char *token_value)
 {
 	sttype_t	*type;
-	stnode_t	*node;
 
-	node = g_new0(stnode_t, 1);
-	node->magic = STNODE_MAGIC;
+	ws_assert_magic(node, STNODE_MAGIC);
+	ws_assert(!node->type);
+	ws_assert(!node->data);
+	ws_assert(!node->token_value);
+	node->flags = 0;
+	node->value = 0;
 
 	if (type_id == STTYPE_UNINITIALIZED) {
 		node->type = NULL;
@@ -103,6 +105,24 @@ stnode_new(sttype_id_t type_id, gpointer data, const char *token_value)
 
 	}
 	node->token_value = g_strdup(token_value);
+}
+
+void
+stnode_init_int(stnode_t *node, sttype_id_t type_id, gint32 value, const char *token_value)
+{
+	stnode_init(node, type_id, NULL, token_value);
+	node->value = value;
+}
+
+stnode_t*
+stnode_new(sttype_id_t type_id, gpointer data, const char *token_value)
+{
+	stnode_t	*node;
+
+	node = g_new0(stnode_t, 1);
+	node->magic = STNODE_MAGIC;
+
+	stnode_init(node, type_id, data, token_value);
 
 	return node;
 }
@@ -136,38 +156,6 @@ stnode_dup(const stnode_t *org)
 }
 
 void
-stnode_init(stnode_t *node, sttype_id_t type_id, gpointer data,  const char *token_value)
-{
-	sttype_t	*type;
-
-	ws_assert_magic(node, STNODE_MAGIC);
-	ws_assert(!node->type);
-	ws_assert(!node->data);
-	ws_assert(!node->token_value);
-
-	type = sttype_lookup(type_id);
-	ws_assert(type);
-	node->type = type;
-	node->flags = 0;
-
-	if (type->func_new) {
-		node->data = type->func_new(data);
-	}
-	else {
-		node->data = data;
-	}
-	node->value = 0;
-	node->token_value = g_strdup(token_value);
-}
-
-void
-stnode_init_int(stnode_t *node, sttype_id_t type_id, gint32 value, const char *token_value)
-{
-	stnode_init(node, type_id, NULL, token_value);
-	node->value = value;
-}
-
-void
 stnode_free(stnode_t *node)
 {
 	ws_assert_magic(node, STNODE_MAGIC);