Add support for 'clear' test, and fix 'default' to expand the result

string if any (used by, for example, rtf).

3 files changed, 32 insertions, 5 deletions

diff --git a/usr.bin/file/magic-load.c b/usr.bin/file/magic-load.c
index 4a62f10226f..00640cdf0b1 100644
--- a/usr.bin/file/magic-load.c
+++ b/usr.bin/file/magic-load.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: magic-load.c,v 1.19 2015/11/15 22:11:18 tobias Exp $ */
+/* $OpenBSD: magic-load.c,v 1.20 2016/05/01 08:48:39 nicm Exp $ */
 
 /*
  * Copyright (c) 2015 Nicholas Marriott <nicm@openbsd.org>
@@ -191,7 +191,6 @@ magic_set_result(struct magic_line *ml, const char *s)
 	else {
 		switch (ml->type) {
 		case MAGIC_TYPE_NONE:
-		case MAGIC_TYPE_DEFAULT:
 		case MAGIC_TYPE_BESTRING16:
 		case MAGIC_TYPE_LESTRING16:
 			return (0); /* don't use result */
@@ -260,6 +259,8 @@ magic_set_result(struct magic_line *ml, const char *s)
 		case MAGIC_TYPE_PSTRING:
 		case MAGIC_TYPE_REGEX:
 		case MAGIC_TYPE_SEARCH:
+		case MAGIC_TYPE_DEFAULT:
+		case MAGIC_TYPE_CLEAR:
 			re = &ml->root->format_string;
 			break;
 		}
@@ -295,6 +296,8 @@ magic_get_strength(struct magic_line *ml)
 	case MAGIC_TYPE_NONE:
 	case MAGIC_TYPE_DEFAULT:
 		return (0);
+	case MAGIC_TYPE_CLEAR:
+		break;
 	case MAGIC_TYPE_BYTE:
 	case MAGIC_TYPE_UBYTE:
 		n += 1 * MAGIC_STRENGTH_MULTIPLIER;
@@ -794,6 +797,8 @@ magic_parse_type(struct magic_line *ml, char **line)
 		ml->type = MAGIC_TYPE_MELDATE;
 	else if (strcmp(s, "default") == 0 || strcmp(s, "udefault") == 0)
 		ml->type = MAGIC_TYPE_DEFAULT;
+	else if (strcmp(s, "clear") == 0 || strcmp(s, "uclear") == 0)
+		ml->type = MAGIC_TYPE_CLEAR;
 	else {
 		magic_warn(ml, "unknown type: %s", s);
 		goto fail;
@@ -836,6 +841,12 @@ magic_parse_value(struct magic_line *ml, char **line)
 		return (0);
 	}
 
+	if (ml->type == MAGIC_TYPE_DEFAULT || ml->type == MAGIC_TYPE_CLEAR) {
+		magic_warn(ml, "test specified for default or clear");
+		ml->test_operator = 'x';
+		return (0);
+	}
+
 	if (**line == '!') {
 		ml->test_not = 1;
 		(*line)++;
diff --git a/usr.bin/file/magic-test.c b/usr.bin/file/magic-test.c
index c2dffd7b0cc..41474ef7dd8 100644
--- a/usr.bin/file/magic-test.c
+++ b/usr.bin/file/magic-test.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: magic-test.c,v 1.19 2016/04/30 22:03:30 nicm Exp $ */
+/* $OpenBSD: magic-test.c,v 1.20 2016/05/01 08:48:39 nicm Exp $ */
 
 /*
  * Copyright (c) 2015 Nicholas Marriott <nicm@openbsd.org>
@@ -1053,9 +1053,20 @@ magic_test_type_search(struct magic_line *ml, struct magic_state *ms)
 static int
 magic_test_type_default(__unused struct magic_line *ml, struct magic_state *ms)
 {
+	if (!ms->matched && ml->result != NULL)
+		magic_add_result(ms, ml, "%s", "");
 	return (!ms->matched);
 }
 
+static int
+magic_test_type_clear(__unused struct magic_line *ml,
+    __unused struct magic_state *ms)
+{
+	if (ml->result != NULL)
+		magic_add_result(ms, ml, "%s", "");
+	return (1);
+}
+
 static int (*magic_test_functions[])(struct magic_line *,
     struct magic_state *) = {
 	magic_test_type_none,
@@ -1119,6 +1130,7 @@ static int (*magic_test_functions[])(struct magic_line *,
 	magic_test_type_regex,
 	magic_test_type_search,
 	magic_test_type_default,
+	magic_test_type_clear,
 };
 
 static int
@@ -1225,7 +1237,10 @@ magic_test_line(struct magic_line *ml, struct magic_state *ms)
 		magic_test_line(child, ms);
 	}
 
-	ms->matched = 1;
+	if (ml->type == MAGIC_TYPE_CLEAR)
+		ms->matched = 0;
+	else
+		ms->matched = 1;
 	return (ml->result != NULL);
 }
 
diff --git a/usr.bin/file/magic.h b/usr.bin/file/magic.h
index 47c25598303..d2258c5db3d 100644
--- a/usr.bin/file/magic.h
+++ b/usr.bin/file/magic.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: magic.h,v 1.12 2016/04/30 21:42:11 nicm Exp $ */
+/* $OpenBSD: magic.h,v 1.13 2016/05/01 08:48:39 nicm Exp $ */
 
 /*
  * Copyright (c) 2015 Nicholas Marriott <nicm@openbsd.org>
@@ -95,6 +95,7 @@ enum magic_type {
 	MAGIC_TYPE_REGEX,
 	MAGIC_TYPE_SEARCH,
 	MAGIC_TYPE_DEFAULT,
+	MAGIC_TYPE_CLEAR,
 };
 
 TAILQ_HEAD(magic_lines, magic_line);