From eccd47c5beb72211ce33c9a33a1bb36366d43e22 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Tue, 25 Aug 2015 19:28:30 +0200 Subject: sd-bus: introduce new match type "arg0has=" for matching arrays of strings Previously, sd-bus inofficially already supported bus matches that tested a string against an array of strings ("as"). This was done via an enhanced way to interpret "arg0=" matches. This is problematic however, since clients have no way to determine if their respective implementation understood strv matches or not, thus allowing invalid matches to be installed without a way to detect that. This patch changes the logic to only allow such matches with a new "arg0has=" syntax. This has the benefit that non-conforming implementations will return a parse error and a client application may thus efficiently detect support for the match type. Matches of this type are useful for "udev"-like systems that "tag" objects with a number of strings, and clients need to be able to match against any of these "tags". The name "has" takes inspiration from Python's ".has_key()" construct. --- src/libsystemd/sd-bus/bus-match.c | 71 +++++++++++++++++++++++++++------------ 1 file changed, 49 insertions(+), 22 deletions(-) (limited to 'src/libsystemd/sd-bus/bus-match.c') diff --git a/src/libsystemd/sd-bus/bus-match.c b/src/libsystemd/sd-bus/bus-match.c index f3b49c0c90..7175cbe8ed 100644 --- a/src/libsystemd/sd-bus/bus-match.c +++ b/src/libsystemd/sd-bus/bus-match.c @@ -61,12 +61,13 @@ */ static inline bool BUS_MATCH_IS_COMPARE(enum bus_match_node_type t) { - return t >= BUS_MATCH_SENDER && t <= BUS_MATCH_ARG_NAMESPACE_LAST; + return t >= BUS_MATCH_SENDER && t <= BUS_MATCH_ARG_HAS_LAST; } static inline bool BUS_MATCH_CAN_HASH(enum bus_match_node_type t) { return (t >= BUS_MATCH_MESSAGE_TYPE && t <= BUS_MATCH_PATH) || - (t >= BUS_MATCH_ARG && t <= BUS_MATCH_ARG_LAST); + (t >= BUS_MATCH_ARG && t <= BUS_MATCH_ARG_LAST) || + (t >= BUS_MATCH_ARG_HAS && t <= BUS_MATCH_ARG_HAS_LAST); } static void bus_match_node_free(struct bus_match_node *node) { @@ -178,12 +179,16 @@ static bool value_node_test( case BUS_MATCH_INTERFACE: case BUS_MATCH_MEMBER: case BUS_MATCH_PATH: - case BUS_MATCH_ARG ... BUS_MATCH_ARG_LAST: { - char **i; + case BUS_MATCH_ARG ... BUS_MATCH_ARG_LAST: if (value_str) return streq_ptr(node->value.str, value_str); + return false; + + case BUS_MATCH_ARG_HAS ... BUS_MATCH_ARG_HAS_LAST: { + char **i; + STRV_FOREACH(i, value_strv) if (streq_ptr(node->value.str, *i)) return true; @@ -191,33 +196,20 @@ static bool value_node_test( return false; } - case BUS_MATCH_ARG_NAMESPACE ... BUS_MATCH_ARG_NAMESPACE_LAST: { - char **i; - + case BUS_MATCH_ARG_NAMESPACE ... BUS_MATCH_ARG_NAMESPACE_LAST: if (value_str) return namespace_simple_pattern(node->value.str, value_str); - STRV_FOREACH(i, value_strv) - if (namespace_simple_pattern(node->value.str, *i)) - return true; return false; - } case BUS_MATCH_PATH_NAMESPACE: return path_simple_pattern(node->value.str, value_str); - case BUS_MATCH_ARG_PATH ... BUS_MATCH_ARG_PATH_LAST: { - char **i; - + case BUS_MATCH_ARG_PATH ... BUS_MATCH_ARG_PATH_LAST: if (value_str) return path_complex_pattern(node->value.str, value_str); - STRV_FOREACH(i, value_strv) - if (path_complex_pattern(node->value.str, *i)) - return true; - return false; - } default: assert_not_reached("Invalid node type"); @@ -248,6 +240,7 @@ static bool value_node_same( case BUS_MATCH_MEMBER: case BUS_MATCH_PATH: case BUS_MATCH_ARG ... BUS_MATCH_ARG_LAST: + case BUS_MATCH_ARG_HAS ... BUS_MATCH_ARG_HAS_LAST: case BUS_MATCH_ARG_NAMESPACE ... BUS_MATCH_ARG_NAMESPACE_LAST: case BUS_MATCH_PATH_NAMESPACE: case BUS_MATCH_ARG_PATH ... BUS_MATCH_ARG_PATH_LAST: @@ -371,15 +364,19 @@ int bus_match_run( break; case BUS_MATCH_ARG ... BUS_MATCH_ARG_LAST: - (void) bus_message_get_arg(m, node->type - BUS_MATCH_ARG, &test_str, &test_strv); + (void) bus_message_get_arg(m, node->type - BUS_MATCH_ARG, &test_str); break; case BUS_MATCH_ARG_PATH ... BUS_MATCH_ARG_PATH_LAST: - (void) bus_message_get_arg(m, node->type - BUS_MATCH_ARG_PATH, &test_str, &test_strv); + (void) bus_message_get_arg(m, node->type - BUS_MATCH_ARG_PATH, &test_str); break; case BUS_MATCH_ARG_NAMESPACE ... BUS_MATCH_ARG_NAMESPACE_LAST: - (void) bus_message_get_arg(m, node->type - BUS_MATCH_ARG_NAMESPACE, &test_str, &test_strv); + (void) bus_message_get_arg(m, node->type - BUS_MATCH_ARG_NAMESPACE, &test_str); + break; + + case BUS_MATCH_ARG_HAS ... BUS_MATCH_ARG_HAS_LAST: + (void) bus_message_get_arg_strv(m, node->type - BUS_MATCH_ARG_HAS, &test_strv); break; default: @@ -742,6 +739,32 @@ enum bus_match_node_type bus_match_node_type_from_string(const char *k, size_t n return t; } + if (n == 7 && startswith(k, "arg") && startswith(k + 4, "has")) { + int j; + + j = undecchar(k[3]); + if (j < 0) + return -EINVAL; + + return BUS_MATCH_ARG_HAS + j; + } + + if (n == 8 && startswith(k, "arg") && startswith(k + 5, "has")) { + enum bus_match_node_type t; + int a, b; + + a = undecchar(k[3]); + b = undecchar(k[4]); + if (a <= 0 || b < 0) + return -EINVAL; + + t = BUS_MATCH_ARG_HAS + a * 10 + b; + if (t > BUS_MATCH_ARG_HAS_LAST) + return -EINVAL; + + return t; + } + return -EINVAL; } @@ -1110,6 +1133,10 @@ const char* bus_match_node_type_to_string(enum bus_match_node_type t, char buf[] snprintf(buf, l, "arg%inamespace", t - BUS_MATCH_ARG_NAMESPACE); return buf; + case BUS_MATCH_ARG_HAS ... BUS_MATCH_ARG_HAS_LAST: + snprintf(buf, l, "arg%ihas", t - BUS_MATCH_ARG_HAS); + return buf; + default: return NULL; } -- cgit v1.2.3-54-g00ecf