+static void part_zero(struct bus_body_part *part, size_t sz) {
+ assert(part);
+ assert(sz > 0);
+ assert(sz < 8);
+
+ /* All other fields can be left in their defaults */
+ assert(!part->data);
+ assert(part->memfd < 0);
+
+ part->size = sz;
+ part->is_zero = true;
+ part->sealed = true;
+}
+
+static int part_make_space(
+ struct sd_bus_message *m,
+ struct bus_body_part *part,
+ size_t sz,
+ void **q) {
+
+ void *n;
+ int r;
+
+ assert(m);
+ assert(part);
+ assert(!part->sealed);
+
+ if (m->poisoned)
+ return -ENOMEM;
+
+ if (!part->data && part->memfd < 0)
+ part->memfd = bus_kernel_pop_memfd(m->bus, &part->data, &part->mapped);
+
+ if (part->memfd >= 0) {
+ uint64_t u = sz;
+
+ r = ioctl(part->memfd, KDBUS_CMD_MEMFD_SIZE_SET, &u);
+ if (r < 0) {
+ m->poisoned = true;
+ return -errno;
+ }
+
+ if (!part->data || sz > part->mapped) {
+ size_t psz = PAGE_ALIGN(sz > 0 ? sz : 1);
+
+ if (part->mapped <= 0)
+ n = mmap(NULL, psz, PROT_READ|PROT_WRITE, MAP_SHARED, part->memfd, 0);
+ else
+ n = mremap(part->data, part->mapped, psz, MREMAP_MAYMOVE);
+
+ if (n == MAP_FAILED) {
+ m->poisoned = true;
+ return -errno;
+ }
+
+ part->mapped = psz;
+ part->data = n;
+ part->munmap_this = true;
+ }
+ } else {
+ n = realloc(part->data, sz);
+ if (!n) {
+ m->poisoned = true;
+ return -ENOMEM;
+ }
+
+ part->data = n;
+ part->free_this = true;
+ }
+
+ if (q)
+ *q = part->data ? (uint8_t*) part->data + part->size : NULL;
+
+ part->size = sz;
+ return 0;
+}
+
+static void message_extend_containers(sd_bus_message *m, size_t expand) {
+ struct bus_container *c;
+
+ assert(m);
+
+ if (expand <= 0)
+ return;
+
+ /* Update counters */
+ for (c = m->containers; c < m->containers + m->n_containers; c++)
+ if (c->array_size)
+ *c->array_size += expand;
+
+}
+
+static void *message_extend_body(sd_bus_message *m, size_t align, size_t sz) {
+ struct bus_body_part *part = NULL;
+ size_t start_body, end_body, padding, start_part, end_part, added;
+ bool add_new_part;
+ void *p;
+ int r;
+
+ assert(m);
+ assert(align > 0);
+ assert(!m->sealed);
+
+ if (m->poisoned)
+ return NULL;
+
+ start_body = ALIGN_TO((size_t) m->header->body_size, align);
+ end_body = start_body + sz;
+
+ padding = start_body - m->header->body_size;
+ added = padding + sz;
+
+ /* Check for 32bit overflows */
+ if (end_body > (size_t) ((uint32_t) -1)) {
+ m->poisoned = true;
+ return NULL;
+ }
+
+ add_new_part =
+ m->n_body_parts <= 0 ||
+ m->body_end->sealed ||
+ padding != ALIGN_TO(m->body_end->size, align) - m->body_end->size;
+
+ if (add_new_part) {
+ if (padding > 0) {
+ part = message_append_part(m);
+ if (!part)
+ return NULL;
+
+ part_zero(part, padding);
+ }
+
+ part = message_append_part(m);
+ if (!part)
+ return NULL;
+
+ r = part_make_space(m, part, sz, &p);
+ if (r < 0)
+ return NULL;
+ } else {
+ struct bus_container *c;
+ void *op;
+ size_t os;
+
+ part = m->body_end;
+ op = part->data;
+ os = part->size;
+
+ start_part = ALIGN_TO(part->size, align);
+ end_part = start_part + sz;
+
+ r = part_make_space(m, part, end_part, &p);
+ if (r < 0)
+ return NULL;
+
+ if (padding > 0) {
+ memset(p, 0, padding);
+ p = (uint8_t*) p + padding;
+ }
+
+ /* Readjust pointers */
+ for (c = m->containers; c < m->containers + m->n_containers; c++)
+ c->array_size = adjust_pointer(c->array_size, op, os, part->data);
+
+ m->error.message = (const char*) adjust_pointer(m->error.message, op, os, part->data);
+ }
+
+ m->header->body_size = end_body;
+ message_extend_containers(m, added);
+
+ return p;
+}
+
+int message_append_basic(sd_bus_message *m, char type, const void *p, const void **stored) {
+ struct bus_container *c;
+ ssize_t align, sz;
+ uint32_t k;