+
+/**
+ * Write to file \a fd \a size bytes from \a buf.
+ * \return The number of bytes written.
+ */
+static size_t battfs_write(struct KFile *fd, const void *_buf, size_t size)
+{
+ BattFs *fdb = BATTFS_CAST(fd);
+ const uint8_t *buf = (const uint8_t *)_buf;
+
+ size_t total_write = 0;
+ pgoff_t pg_offset;
+ pgaddr_t addr_offset;
+ pgaddr_t wr_len;
+
+ size = MIN((kfile_off_t)size, fd->size - fd->seek_pos);
+
+ while (size)
+ {
+ #warning TODO: outside EOF?
+
+ pg_offset = fd->seek_pos / (fdb->disk->page_size - BATTFS_HEADER_LEN);
+ addr_offset = fd->seek_pos % (fdb->disk->page_size - BATTFS_HEADER_LEN);
+ wr_len = MIN(size, (size_t)(fdb->disk->page_size - BATTFS_HEADER_LEN - addr_offset));
+
+
+ if (fdb->start[pg_offset] != fdb->disk->curr_page)
+ {
+ if (!battfs_loadPage(fdb->disk, fdb->start[pg_offset]))
+ {
+ #warning TODO set error?
+ return total_write;
+ }
+
+ /* Get a free page */
+ fdb->disk->curr_page = fdb->disk->page_array[fdb->disk->free_page_start];
+ movePages(fdb->disk, fdb->disk->free_page_start + 1, -1);
+
+ /* Insert previous page in free blocks list */
+ fdb->disk->page_array[fdb->disk->page_count - 1] = fdb->start[pg_offset];
+ /* Assign new page */
+ fdb->start[pg_offset] = fdb->disk->curr_page;
+ #warning TODO: hdr have to be updated!
+ }
+
+
+ if (fdb->disk->bufferWrite(fdb->disk, addr_offset, buf, wr_len) != wr_len)
+ {
+ #warning TODO set error?
+ }
+ fdb->disk->cache_dirty = true;
+
+ size -= wr_len;
+ fd->seek_pos += wr_len;
+ total_write += wr_len;
+ buf += wr_len;
+ #warning TODO: hdr have to be updated!
+ }
+ return total_write;
+
+}
+
+