bus: add support for serializing to gvariant

(deserialization is still missing, hence this is not hooked up to kdbus)

1 files changed, 189 insertions, 0 deletions

diff --git a/src/libsystemd-bus/bus-gvariant.c b/src/libsystemd-bus/bus-gvariant.c
new file mode 100644
index 0000000000..d2e134e0e2
--- /dev/null
+++ b/src/libsystemd-bus/bus-gvariant.c
@@ -0,0 +1,189 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2013 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "util.h"
+#include "bus-type.h"
+#include "bus-gvariant.h"
+#include "bus-signature.h"
+
+int bus_gvariant_get_size(char c) {
+
+        switch (c) {
+
+        case SD_BUS_TYPE_BOOLEAN:
+        case SD_BUS_TYPE_BYTE:
+                return 1;
+
+        case SD_BUS_TYPE_INT16:
+        case SD_BUS_TYPE_UINT16:
+                return 2;
+
+        case SD_BUS_TYPE_INT32:
+        case SD_BUS_TYPE_UINT32:
+        case SD_BUS_TYPE_UNIX_FD:
+                return 4;
+
+        case SD_BUS_TYPE_INT64:
+        case SD_BUS_TYPE_UINT64:
+        case SD_BUS_TYPE_DOUBLE:
+                return 8;
+        }
+
+        return -EINVAL;
+}
+
+int bus_gvariant_get_alignment(const char *signature) {
+        size_t alignment = 1;
+        const char *p;
+        int r;
+
+        p = signature;
+        while (*p != 0 && alignment < 8) {
+                size_t n;
+                int a;
+
+                r = signature_element_length(p, &n);
+                if (r < 0)
+                        return r;
+
+                switch (*p) {
+
+                case SD_BUS_TYPE_BYTE:
+                case SD_BUS_TYPE_BOOLEAN:
+                case SD_BUS_TYPE_STRING:
+                case SD_BUS_TYPE_OBJECT_PATH:
+                case SD_BUS_TYPE_SIGNATURE:
+                        a = 1;
+                        break;
+
+                case SD_BUS_TYPE_INT16:
+                case SD_BUS_TYPE_UINT16:
+                        a = 2;
+                        break;
+
+                case SD_BUS_TYPE_INT32:
+                case SD_BUS_TYPE_UINT32:
+                case SD_BUS_TYPE_UNIX_FD:
+                        a = 4;
+                        break;
+
+                case SD_BUS_TYPE_INT64:
+                case SD_BUS_TYPE_UINT64:
+                case SD_BUS_TYPE_DOUBLE:
+                case SD_BUS_TYPE_VARIANT:
+                        a = 8;
+                        break;
+
+                case SD_BUS_TYPE_ARRAY: {
+                        char t[n];
+
+                        memcpy(t, p + 1, n - 1);
+                        t[n - 1] = 0;
+
+                        a = bus_gvariant_get_alignment(t);
+                        break;
+                }
+
+                case SD_BUS_TYPE_STRUCT_BEGIN:
+                case SD_BUS_TYPE_DICT_ENTRY_BEGIN: {
+                        char t[n-1];
+
+                        memcpy(t, p + 1, n - 2);
+                        t[n - 2] = 0;
+
+                        a = bus_gvariant_get_alignment(t);
+                        break;
+                }
+
+                default:
+                        assert_not_reached("Unknown signature type");
+                }
+
+                if (a < 0)
+                        return a;
+
+                assert(a > 0 && a <= 8);
+                if ((size_t) a > alignment)
+                        alignment = (size_t) a;
+
+                p += n;
+        }
+
+        return alignment;
+}
+
+int bus_gvariant_is_fixed_size(const char *signature) {
+        const char *p;
+        int r;
+
+        assert(signature);
+
+        p = signature;
+        while (*p != 0) {
+                size_t n;
+
+                r = signature_element_length(p, &n);
+                if (r < 0)
+                        return r;
+
+                switch (*p) {
+
+                case SD_BUS_TYPE_STRING:
+                case SD_BUS_TYPE_OBJECT_PATH:
+                case SD_BUS_TYPE_SIGNATURE:
+                case SD_BUS_TYPE_ARRAY:
+                case SD_BUS_TYPE_VARIANT:
+                        return 0;
+
+                case SD_BUS_TYPE_BYTE:
+                case SD_BUS_TYPE_BOOLEAN:
+                case SD_BUS_TYPE_INT16:
+                case SD_BUS_TYPE_UINT16:
+                case SD_BUS_TYPE_INT32:
+                case SD_BUS_TYPE_UINT32:
+                case SD_BUS_TYPE_UNIX_FD:
+                case SD_BUS_TYPE_INT64:
+                case SD_BUS_TYPE_UINT64:
+                case SD_BUS_TYPE_DOUBLE:
+                        break;
+
+                case SD_BUS_TYPE_STRUCT_BEGIN:
+                case SD_BUS_TYPE_DICT_ENTRY_BEGIN: {
+                        char t[n-1];
+
+                        memcpy(t, p + 1, n - 2);
+                        t[n - 2] = 0;
+
+                        r = bus_gvariant_is_fixed_size(t);
+                        if (r <= 0)
+                                return r;
+                        break;
+                }
+
+                default:
+                        assert_not_reached("Unknown signature type");
+                }
+
+                p += n;
+        }
+
+        return true;
+}