+ if (!validate_signature(q, l))
+ return -EBADMSG;
+
+ *contents = q;
+ }
+
+ if (type)
+ *type = SD_BUS_TYPE_VARIANT;
+
+ return 1;
+ }
+
+ return -EINVAL;
+
+eof:
+ if (type)
+ *type = c->enclosing;
+ if (contents)
+ *contents = NULL;
+ return 0;
+}
+
+int sd_bus_message_rewind(sd_bus_message *m, int complete) {
+ struct bus_container *c;
+
+ if (!m)
+ return -EINVAL;
+ if (!m->sealed)
+ return -EPERM;
+
+ if (complete) {
+ message_reset_containers(m);
+ m->rindex = 0;
+ m->root_container.index = 0;
+
+ c = message_get_container(m);
+ } else {
+ c = message_get_container(m);
+
+ c->index = 0;
+ m->rindex = c->begin;
+ }
+
+ return !isempty(c->signature);
+}
+static int message_read_ap(
+ sd_bus_message *m,
+ const char *types,
+ va_list ap) {
+
+ unsigned n_array, n_struct;
+ TypeStack stack[BUS_CONTAINER_DEPTH];
+ unsigned stack_ptr = 0;
+ int r;
+
+ assert(m);
+
+ if (!types)
+ return 0;
+
+ /* Ideally, we'd just call ourselves recursively on every
+ * complex type. However, the state of a va_list that is
+ * passed to a function is undefined after that function
+ * returns. This means we need to docode the va_list linearly
+ * in a single stackframe. We hence implement our own
+ * home-grown stack in an array. */
+
+ n_array = (unsigned) -1;
+ n_struct = strlen(types);
+
+ for (;;) {
+ const char *t;
+
+ if (n_array == 0 || (n_array == (unsigned) -1 && n_struct == 0)) {
+ r = type_stack_pop(stack, ELEMENTSOF(stack), &stack_ptr, &types, &n_struct, &n_array);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ break;
+
+ r = sd_bus_message_exit_container(m);
+ if (r < 0)
+ return r;
+
+ continue;
+ }
+
+ t = types;
+ if (n_array != (unsigned) -1)
+ n_array --;
+ else {
+ types ++;
+ n_struct--;
+ }
+
+ switch (*t) {
+
+ 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_INT64:
+ case SD_BUS_TYPE_UINT64:
+ case SD_BUS_TYPE_DOUBLE:
+ case SD_BUS_TYPE_STRING:
+ case SD_BUS_TYPE_OBJECT_PATH:
+ case SD_BUS_TYPE_SIGNATURE:
+ case SD_BUS_TYPE_UNIX_FD: {
+ void *p;
+
+ p = va_arg(ap, void*);
+ r = sd_bus_message_read_basic(m, *t, p);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -ENXIO;
+
+ break;
+ }
+
+ case SD_BUS_TYPE_ARRAY: {
+ size_t k;
+
+ r = signature_element_length(t + 1, &k);
+ if (r < 0)
+ return r;
+
+ {
+ char s[k + 1];
+ memcpy(s, t + 1, k);
+ s[k] = 0;
+
+ r = sd_bus_message_enter_container(m, SD_BUS_TYPE_ARRAY, s);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -ENXIO;
+ }
+
+ if (n_array == (unsigned) -1) {
+ types += k;
+ n_struct -= k;
+ }
+
+ r = type_stack_push(stack, ELEMENTSOF(stack), &stack_ptr, types, n_struct, n_array);
+ if (r < 0)
+ return r;
+
+ types = t + 1;
+ n_struct = k;
+ n_array = va_arg(ap, unsigned);
+
+ break;
+ }
+
+ case SD_BUS_TYPE_VARIANT: {
+ const char *s;
+
+ s = va_arg(ap, const char *);
+ if (!s)
+ return -EINVAL;
+
+ r = sd_bus_message_enter_container(m, SD_BUS_TYPE_VARIANT, s);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -ENXIO;
+
+ r = type_stack_push(stack, ELEMENTSOF(stack), &stack_ptr, types, n_struct, n_array);
+ if (r < 0)
+ return r;
+
+ types = s;
+ n_struct = strlen(s);
+ n_array = (unsigned) -1;
+
+ break;
+ }
+
+ case SD_BUS_TYPE_STRUCT_BEGIN:
+ case SD_BUS_TYPE_DICT_ENTRY_BEGIN: {
+ size_t k;
+
+ r = signature_element_length(t, &k);
+ if (r < 0)
+ return r;
+
+ {
+ char s[k - 1];
+ memcpy(s, t + 1, k - 2);
+ s[k - 2] = 0;
+
+ r = sd_bus_message_enter_container(m, *t == SD_BUS_TYPE_STRUCT_BEGIN ? SD_BUS_TYPE_STRUCT : SD_BUS_TYPE_DICT_ENTRY, s);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -ENXIO;
+ }
+
+ if (n_array == (unsigned) -1) {
+ types += k - 1;
+ n_struct -= k - 1;
+ }
+
+ r = type_stack_push(stack, ELEMENTSOF(stack), &stack_ptr, types, n_struct, n_array);
+ if (r < 0)
+ return r;
+
+ types = t + 1;
+ n_struct = k - 2;
+ n_array = (unsigned) -1;
+
+ break;
+ }
+
+ default:
+ return -EINVAL;
+ }
+ }
+
+ return 1;
+}
+
+int sd_bus_message_read(sd_bus_message *m, const char *types, ...) {
+ va_list ap;
+ int r;
+
+ if (!m)
+ return -EINVAL;
+ if (!m->sealed)
+ return -EPERM;
+ if (!types)
+ return -EINVAL;
+
+ va_start(ap, types);
+ r = message_read_ap(m, types, ap);
+ va_end(ap);
+
+ return r;
+}
+
+int sd_bus_message_read_array(sd_bus_message *m, char type, const void **ptr, size_t *size) {
+ struct bus_container *c;
+ void *p;
+ size_t sz;
+ ssize_t align;
+ int r;
+
+ if (!m)
+ return -EINVAL;
+ if (!m->sealed)
+ return -EPERM;
+ if (!bus_type_is_trivial(type))
+ return -EINVAL;
+ if (!ptr)
+ return -EINVAL;
+ if (!size)
+ return -EINVAL;
+ if (BUS_MESSAGE_NEED_BSWAP(m))
+ return -ENOTSUP;
+
+ align = bus_type_get_alignment(type);
+ if (align < 0)
+ return align;
+
+ r = sd_bus_message_enter_container(m, SD_BUS_TYPE_ARRAY, CHAR_TO_STR(type));
+ if (r <= 0)
+ return r;
+
+ c = message_get_container(m);
+ sz = BUS_MESSAGE_BSWAP32(m, *c->array_size);
+
+ r = message_peek_body(m, &m->rindex, align, sz, &p);
+ if (r < 0)
+ goto fail;
+ if (r == 0) {
+ r = -EBADMSG;
+ goto fail;
+ }
+
+ r = sd_bus_message_exit_container(m);
+ if (r < 0)
+ goto fail;
+
+ *ptr = (const void*) p;
+ *size = sz;
+
+ return 1;
+
+fail:
+ message_quit_container(m);
+ return r;
+}
+
+static int message_peek_fields(
+ sd_bus_message *m,
+ size_t *rindex,
+ size_t align,
+ size_t nbytes,
+ void **ret) {
+
+ assert(m);
+ assert(rindex);
+ assert(align > 0);
+
+ return buffer_peek(BUS_MESSAGE_FIELDS(m), BUS_MESSAGE_FIELDS_SIZE(m), rindex, align, nbytes, ret);
+}
+
+static int message_peek_field_uint32(
+ sd_bus_message *m,
+ size_t *ri,
+ uint32_t *ret) {
+
+ int r;
+ void *q;
+
+ assert(m);
+ assert(ri);
+
+ r = message_peek_fields(m, ri, 4, 4, &q);
+ if (r < 0)
+ return r;
+
+ if (ret)
+ *ret = BUS_MESSAGE_BSWAP32(m, *(uint32_t*) q);
+
+ return 0;
+}
+
+static int message_peek_field_string(
+ sd_bus_message *m,
+ bool (*validate)(const char *p),
+ size_t *ri,
+ const char **ret) {
+
+ uint32_t l;
+ int r;
+ void *q;
+
+ assert(m);
+ assert(ri);
+
+ r = message_peek_field_uint32(m, ri, &l);
+ if (r < 0)
+ return r;
+
+ r = message_peek_fields(m, ri, 1, l+1, &q);
+ if (r < 0)
+ return r;
+
+ if (validate) {
+ if (!validate_nul(q, l))
+ return -EBADMSG;
+
+ if (!validate(q))
+ return -EBADMSG;
+ } else {
+ if (!validate_string(q, l))
+ return -EBADMSG;
+ }
+
+ if (ret)
+ *ret = q;
+
+ return 0;
+}
+
+static int message_peek_field_signature(
+ sd_bus_message *m,
+ size_t *ri,
+ const char **ret) {
+
+ size_t l;
+ int r;
+ void *q;
+
+ assert(m);
+ assert(ri);
+
+ r = message_peek_fields(m, ri, 1, 1, &q);
+ if (r < 0)
+ return r;
+
+ l = *(uint8_t*) q;
+ r = message_peek_fields(m, ri, 1, l+1, &q);
+ if (r < 0)
+ return r;
+
+ if (!validate_signature(q, l))
+ return -EBADMSG;
+
+ if (ret)
+ *ret = q;
+
+ return 0;
+}
+
+static int message_skip_fields(
+ sd_bus_message *m,
+ size_t *ri,
+ uint32_t array_size,
+ const char **signature) {
+
+ size_t original_index;
+ int r;
+
+ assert(m);
+ assert(ri);
+ assert(signature);
+
+ original_index = *ri;
+
+ for (;;) {
+ char t;
+ size_t l;
+
+ if (array_size != (uint32_t) -1 &&
+ array_size <= *ri - original_index)
+ return 0;
+
+ t = **signature;
+ if (!t)
+ return 0;
+
+ if (t == SD_BUS_TYPE_STRING) {
+
+ r = message_peek_field_string(m, NULL, ri, NULL);
+ if (r < 0)
+ return r;
+
+ (*signature)++;
+
+ } else if (t == SD_BUS_TYPE_OBJECT_PATH) {
+
+ r = message_peek_field_string(m, object_path_is_valid, ri, NULL);
+ if (r < 0)
+ return r;
+
+ (*signature)++;
+
+ } else if (t == SD_BUS_TYPE_SIGNATURE) {
+
+ r = message_peek_field_signature(m, ri, NULL);
+ if (r < 0)
+ return r;
+
+ (*signature)++;
+
+ } else if (bus_type_is_basic(t)) {
+ ssize_t align, k;
+
+ align = bus_type_get_alignment(t);
+ k = bus_type_get_size(t);
+ assert(align > 0 && k > 0);
+
+ r = message_peek_fields(m, ri, align, k, NULL);
+ if (r < 0)
+ return r;
+
+ (*signature)++;
+
+ } else if (t == SD_BUS_TYPE_ARRAY) {
+
+ r = signature_element_length(*signature+1, &l);
+ if (r < 0)
+ return r;
+
+ assert(l >= 1);
+ {
+ char sig[l-1], *s;
+ uint32_t nas;
+ int alignment;
+
+ strncpy(sig, *signature + 1, l-1);
+ s = sig;
+
+ alignment = bus_type_get_alignment(sig[0]);
+ if (alignment < 0)
+ return alignment;
+
+ r = message_peek_field_uint32(m, ri, &nas);
+ if (r < 0)
+ return r;
+ if (nas > BUS_ARRAY_MAX_SIZE)
+ return -EBADMSG;
+
+ r = message_peek_fields(m, ri, alignment, 0, NULL);
+ if (r < 0)
+ return r;
+
+ r = message_skip_fields(m, ri, nas, (const char**) &s);
+ if (r < 0)
+ return r;
+ }
+
+ (*signature) += 1 + l;
+
+ } else if (t == SD_BUS_TYPE_VARIANT) {
+ const char *s;
+
+ r = message_peek_field_signature(m, ri, &s);
+ if (r < 0)
+ return r;
+
+ r = message_skip_fields(m, ri, (uint32_t) -1, (const char**) &s);
+ if (r < 0)
+ return r;
+
+ (*signature)++;
+
+ } else if (t == SD_BUS_TYPE_STRUCT ||
+ t == SD_BUS_TYPE_DICT_ENTRY) {
+
+ r = signature_element_length(*signature, &l);
+ if (r < 0)
+ return r;
+
+ assert(l >= 2);
+ {
+ char sig[l-1], *s;
+ strncpy(sig, *signature + 1, l-1);
+ s = sig;
+
+ r = message_skip_fields(m, ri, (uint32_t) -1, (const char**) &s);
+ if (r < 0)
+ return r;
+ }
+
+ *signature += l;
+ } else
+ return -EINVAL;
+ }
+}
+
+int bus_message_parse_fields(sd_bus_message *m) {
+ size_t ri;
+ int r;
+ uint32_t unix_fds = 0;
+
+ assert(m);
+
+ for (ri = 0; ri < BUS_MESSAGE_FIELDS_SIZE(m); ) {
+ const char *signature;
+ uint8_t *header;
+
+ r = message_peek_fields(m, &ri, 8, 1, (void**) &header);
+ if (r < 0)
+ return r;
+
+ r = message_peek_field_signature(m, &ri, &signature);
+ if (r < 0)
+ return r;
+
+ switch (*header) {
+ case _SD_BUS_MESSAGE_HEADER_INVALID:
+ return -EBADMSG;