Function ashmem_create_region

app/src/main/cpp/utils/shared_memory.cpp:106–137

* ashmem_create_region - creates a new ashmem region and returns the file * descriptor, or <0 on error * * `name' is an optional label to give the region (visible in /proc/pid/maps) * `size' is the size of the region, in page-aligned bytes */

 * `size' is the size of the region, in page-aligned bytes
 */
int ashmem_create_region(const char *name, size_t size) {
    int ret, save_errno;
    size_t pagesize = getpagesize();
    if (size % pagesize != 0) {
        size = pagesize * (size / pagesize + 1);
    }
    if (has_memfd_support()) {
        return memfd_create_region_post_q(name ? name : "none", size);
    }
    int fd = ashmem_open_legacy();
    if (fd < 0) {
        return fd;
    }
    if (name) {
        char buf[ASHMEM_NAME_LEN] = {0};
        strncpy(buf, name, sizeof(buf));
        ret = TEMP_FAILURE_RETRY(ioctl(fd, ASHMEM_SET_NAME, buf));
        if (ret < 0) {
            goto L_ERROR;
        }
    }
    ret = TEMP_FAILURE_RETRY(ioctl(fd, ASHMEM_SET_SIZE, size));
    if (ret < 0) {
        goto L_ERROR;
    }
    return fd;
    L_ERROR:
    save_errno = errno;
    close(fd);
    errno = save_errno;
    return ret;
}

int copy_file_to_memfd(int fd, const char *name) {
    if (!has_memfd_support()) {