Split fstree inode serialization, move independend part to libsquashfs.so

This commit adds a function to libsquashfs.so for writing generic inodes
to a meta writer and another function to libsqfshelper.a that turns a
tree node to an inode. That way, the tree serialization code can be
expressed in terms of those functions and a bulk of the independend code
can be moved over to libsquashfs.so

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 149 insertions, 0 deletions

diff --git a/lib/sqfs/write_inode.c b/lib/sqfs/write_inode.c
new file mode 100644
index 0000000..a2d87f9
--- /dev/null
+++ b/lib/sqfs/write_inode.c
@@ -0,0 +1,149 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * write_inode.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+
+#include "sqfs/inode.h"
+
+static int write_block_sizes(meta_writer_t *ir, sqfs_inode_generic_t *n,
+			     size_t file_num_blocks)
+{
+	uint32_t sizes[file_num_blocks];
+	size_t i;
+
+	for (i = 0; i < file_num_blocks; ++i)
+		sizes[i] = htole32(n->block_sizes[i]);
+
+	return meta_writer_append(ir, sizes,
+				  sizeof(uint32_t) * file_num_blocks);
+}
+
+int meta_writer_write_inode(meta_writer_t *ir, sqfs_inode_generic_t *n,
+			    size_t file_num_blocks)
+{
+	sqfs_inode_t base;
+
+	base.type = htole16(n->base.type);
+	base.mode = htole16(n->base.mode);
+	base.uid_idx = htole16(n->base.uid_idx);
+	base.gid_idx = htole16(n->base.gid_idx);
+	base.mod_time = htole32(n->base.mod_time);
+	base.inode_number = htole32(n->base.inode_number);
+
+	if (meta_writer_append(ir, &base, sizeof(base)))
+		return -1;
+
+	switch (n->base.type) {
+	case SQFS_INODE_DIR: {
+		sqfs_inode_dir_t dir = {
+			.start_block = htole32(n->data.dir.start_block),
+			.nlink = htole32(n->data.dir.nlink),
+			.size = htole16(n->data.dir.size),
+			.offset = htole16(n->data.dir.offset),
+			.parent_inode = htole32(n->data.dir.parent_inode),
+		};
+		return meta_writer_append(ir, &dir, sizeof(dir));
+	}
+	case SQFS_INODE_FILE: {
+		sqfs_inode_file_t file = {
+			.blocks_start = htole32(n->data.file.blocks_start),
+			.fragment_index = htole32(n->data.file.fragment_index),
+			.fragment_offset =
+				htole32(n->data.file.fragment_offset),
+			.file_size = htole32(n->data.file.file_size),
+		};
+		if (meta_writer_append(ir, &file, sizeof(file)))
+			return -1;
+		return write_block_sizes(ir, n, file_num_blocks);
+	}
+	case SQFS_INODE_SLINK: {
+		sqfs_inode_slink_t slink = {
+			.nlink = htole32(n->data.slink.nlink),
+			.target_size = htole32(n->data.slink.target_size),
+		};
+		if (meta_writer_append(ir, &slink, sizeof(slink)))
+			return -1;
+		return meta_writer_append(ir, n->slink_target,
+					  n->data.slink.target_size);
+	}
+	case SQFS_INODE_BDEV:
+	case SQFS_INODE_CDEV: {
+		sqfs_inode_dev_t dev = {
+			.nlink = htole32(n->data.dev.nlink),
+			.devno = htole32(n->data.dev.devno),
+		};
+		return meta_writer_append(ir, &dev, sizeof(dev));
+	}
+	case SQFS_INODE_FIFO:
+	case SQFS_INODE_SOCKET: {
+		sqfs_inode_ipc_t ipc = {
+			.nlink = htole32(n->data.ipc.nlink),
+		};
+		return meta_writer_append(ir, &ipc, sizeof(ipc));
+	}
+	case SQFS_INODE_EXT_DIR: {
+		sqfs_inode_dir_ext_t dir = {
+			.nlink = htole32(n->data.dir_ext.nlink),
+			.size = htole32(n->data.dir_ext.size),
+			.start_block = htole32(n->data.dir_ext.start_block),
+			.parent_inode = htole32(n->data.dir_ext.parent_inode),
+			.inodex_count = htole16(n->data.dir_ext.inodex_count),
+			.offset = htole16(n->data.dir_ext.offset),
+			.xattr_idx = htole32(n->data.dir_ext.xattr_idx),
+		};
+		return meta_writer_append(ir, &dir, sizeof(dir));
+	}
+	case SQFS_INODE_EXT_FILE: {
+		sqfs_inode_file_ext_t file = {
+			.blocks_start = htole64(n->data.file_ext.blocks_start),
+			.file_size = htole64(n->data.file_ext.file_size),
+			.sparse = htole64(n->data.file_ext.sparse),
+			.nlink = htole32(n->data.file_ext.nlink),
+			.fragment_idx = htole32(n->data.file_ext.fragment_idx),
+			.fragment_offset =
+				htole32(n->data.file_ext.fragment_offset),
+			.xattr_idx = htole32(n->data.file_ext.xattr_idx),
+		};
+		if (meta_writer_append(ir, &file, sizeof(file)))
+			return -1;
+		return write_block_sizes(ir, n, file_num_blocks);
+	}
+	case SQFS_INODE_EXT_SLINK: {
+		sqfs_inode_slink_t slink = {
+			.nlink = htole32(n->data.slink_ext.nlink),
+			.target_size = htole32(n->data.slink_ext.target_size),
+		};
+		uint32_t xattr = htole32(n->data.slink_ext.xattr_idx);
+
+		if (meta_writer_append(ir, &slink, sizeof(slink)))
+			return -1;
+		if (meta_writer_append(ir, n->slink_target,
+				       n->data.slink_ext.target_size)) {
+			return -1;
+		}
+		return meta_writer_append(ir, &xattr, sizeof(xattr));
+	}
+	case SQFS_INODE_EXT_BDEV:
+	case SQFS_INODE_EXT_CDEV: {
+		sqfs_inode_dev_ext_t dev = {
+			.nlink = htole32(n->data.dev_ext.nlink),
+			.devno = htole32(n->data.dev_ext.devno),
+			.xattr_idx = htole32(n->data.dev_ext.xattr_idx),
+		};
+		return meta_writer_append(ir, &dev, sizeof(dev));
+	}
+	case SQFS_INODE_EXT_FIFO:
+	case SQFS_INODE_EXT_SOCKET: {
+		sqfs_inode_ipc_ext_t ipc = {
+			.nlink = htole32(n->data.ipc_ext.nlink),
+			.xattr_idx = htole32(n->data.ipc_ext.xattr_idx),
+		};
+		return meta_writer_append(ir, &ipc, sizeof(ipc));
+	}
+	}
+
+	return -1;
+}