Split libsquashfs.a into low seperate libraries

The idea is to make libsquashfs.a independend of libfstree.a, so it becomes
a general purpose squashfs manipulation library. All the high level glue code
for libfstree.a and utilites that are overly specific with to tools are moved
to a seperate librarby.

This commit makes the first step by moving the stuff with dependencies on
libfstree to a seperate library.

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

1 files changed, 327 insertions, 0 deletions

diff --git a/lib/sqfshelper/write_inode.c b/lib/sqfshelper/write_inode.c
new file mode 100644
index 0000000..1295fa9
--- /dev/null
+++ b/lib/sqfshelper/write_inode.c
@@ -0,0 +1,327 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * write_inode.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+
+#include "meta_writer.h"
+#include "util.h"
+
+#include <assert.h>
+#include <endian.h>
+#include <stdlib.h>
+#include <string.h>
+
+static size_t hard_link_count(tree_node_t *n)
+{
+	size_t count;
+
+	if (S_ISDIR(n->mode)) {
+		count = 2;
+
+		for (n = n->data.dir->children; n != NULL; n = n->next)
+			++count;
+
+		return count;
+	}
+
+	return 1;
+}
+
+static int get_type(tree_node_t *node)
+{
+	switch (node->mode & S_IFMT) {
+	case S_IFSOCK:
+		if (node->xattr != NULL)
+			return SQFS_INODE_EXT_SOCKET;
+		return SQFS_INODE_SOCKET;
+	case S_IFIFO:
+		if (node->xattr != NULL)
+			return SQFS_INODE_EXT_FIFO;
+		return SQFS_INODE_FIFO;
+	case S_IFLNK:
+		if (node->xattr != NULL)
+			return SQFS_INODE_EXT_SLINK;
+		return SQFS_INODE_SLINK;
+	case S_IFBLK:
+		if (node->xattr != NULL)
+			return SQFS_INODE_EXT_BDEV;
+		return SQFS_INODE_BDEV;
+	case S_IFCHR:
+		if (node->xattr != NULL)
+			return SQFS_INODE_EXT_CDEV;
+		return SQFS_INODE_CDEV;
+	case S_IFREG: {
+		file_info_t *fi = node->data.file;
+
+		if (node->xattr != NULL || fi->sparse > 0)
+			return SQFS_INODE_EXT_FILE;
+
+		if (fi->startblock > 0xFFFFFFFFUL || fi->size > 0xFFFFFFFFUL)
+			return SQFS_INODE_EXT_FILE;
+
+		if (hard_link_count(node) > 1)
+			return SQFS_INODE_EXT_FILE;
+
+		return SQFS_INODE_FILE;
+	}
+	case S_IFDIR: {
+		dir_info_t *di = node->data.dir;
+
+		if (node->xattr != NULL)
+			return SQFS_INODE_EXT_DIR;
+
+		if (di->start_block > 0xFFFFFFFFUL || di->size > 0xFFFF)
+			return SQFS_INODE_EXT_DIR;
+
+		return SQFS_INODE_DIR;
+	}
+	}
+	assert(0);
+}
+
+static int write_file_blocks(fstree_t *fs, file_info_t *fi, meta_writer_t *im)
+{
+	uint64_t i, count = fi->size / fs->block_size;
+	uint32_t bs;
+
+	if ((fi->size % fs->block_size) != 0 &&
+	    !(fi->flags & FILE_FLAG_HAS_FRAGMENT)) {
+		++count;
+	}
+
+	for (i = 0; i < count; ++i) {
+		bs = htole32(fi->blocks[i].size);
+
+		if (meta_writer_append(im, &bs, sizeof(bs)))
+			return -1;
+	}
+	return 0;
+}
+
+static int write_dir_index(dir_index_t *diridx, meta_writer_t *im)
+{
+	sqfs_dir_index_t idx;
+	size_t i;
+
+	for (i = 0; i < diridx->num_nodes; ++i) {
+		idx.start_block = htole32(diridx->idx_nodes[i].block);
+		idx.index = htole32(diridx->idx_nodes[i].index);
+		idx.size = strlen(diridx->idx_nodes[i].node->name) - 1;
+		idx.size = htole32(idx.size);
+
+		if (meta_writer_append(im, &idx, sizeof(idx)))
+			return -1;
+
+		if (meta_writer_append(im, diridx->idx_nodes[i].node->name,
+				       le32toh(idx.size) + 1)) {
+			return -1;
+		}
+	}
+	return 0;
+}
+
+int meta_writer_write_inode(fstree_t *fs, id_table_t *idtbl, meta_writer_t *im,
+			    meta_writer_t *dm, tree_node_t *node)
+{
+	dir_index_t *diridx = NULL;
+	uint16_t uid_idx, gid_idx;
+	sqfs_inode_t base;
+	uint32_t offset;
+	uint64_t block;
+
+	if (id_table_id_to_index(idtbl, node->uid, &uid_idx))
+		return -1;
+
+	if (id_table_id_to_index(idtbl, node->gid, &gid_idx))
+		return -1;
+
+	meta_writer_get_position(im, &block, &offset);
+	node->inode_ref = (block << 16) | offset;
+
+	if (S_ISDIR(node->mode)) {
+		if (meta_writer_write_dir(dm, node->data.dir, &diridx))
+			return -1;
+	}
+
+	base.type = htole16(get_type(node));
+	base.mode = htole16(node->mode);
+	base.uid_idx = htole16(uid_idx);
+	base.gid_idx = htole16(gid_idx);
+	base.mod_time = htole32(node->mod_time);
+	base.inode_number = htole32(node->inode_num);
+
+	if (meta_writer_append(im, &base, sizeof(base))) {
+		free(diridx);
+		return -1;
+	}
+
+	switch (le16toh(base.type)) {
+	case SQFS_INODE_FIFO:
+	case SQFS_INODE_SOCKET: {
+		sqfs_inode_ipc_t ipc = {
+			.nlink = htole32(hard_link_count(node)),
+		};
+
+		return meta_writer_append(im, &ipc, sizeof(ipc));
+	}
+	case SQFS_INODE_EXT_FIFO:
+	case SQFS_INODE_EXT_SOCKET: {
+		sqfs_inode_ipc_ext_t ipc = {
+			.nlink = htole32(hard_link_count(node)),
+			.xattr_idx = htole32(0xFFFFFFFF),
+		};
+
+		if (node->xattr != NULL)
+			ipc.xattr_idx = htole32(node->xattr->index);
+
+		return meta_writer_append(im, &ipc, sizeof(ipc));
+	}
+	case SQFS_INODE_SLINK: {
+		sqfs_inode_slink_t slink = {
+			.nlink = htole32(hard_link_count(node)),
+			.target_size = htole32(strlen(node->data.slink_target)),
+		};
+
+		if (meta_writer_append(im, &slink, sizeof(slink)))
+			return -1;
+		if (meta_writer_append(im, node->data.slink_target,
+				       le32toh(slink.target_size))) {
+			return -1;
+		}
+		break;
+	}
+	case SQFS_INODE_EXT_SLINK: {
+		sqfs_inode_slink_t slink = {
+			.nlink = htole32(hard_link_count(node)),
+			.target_size = htole32(strlen(node->data.slink_target)),
+		};
+		uint32_t xattr = htole32(0xFFFFFFFF);
+
+		if (node->xattr != NULL)
+			xattr = htole32(node->xattr->index);
+
+		if (meta_writer_append(im, &slink, sizeof(slink)))
+			return -1;
+		if (meta_writer_append(im, node->data.slink_target,
+				       le32toh(slink.target_size))) {
+			return -1;
+		}
+		if (meta_writer_append(im, &xattr, sizeof(xattr)))
+			return -1;
+		break;
+	}
+	case SQFS_INODE_BDEV:
+	case SQFS_INODE_CDEV: {
+		sqfs_inode_dev_t dev = {
+			.nlink = htole32(hard_link_count(node)),
+			.devno = htole32(node->data.devno),
+		};
+
+		return meta_writer_append(im, &dev, sizeof(dev));
+	}
+	case SQFS_INODE_EXT_BDEV:
+	case SQFS_INODE_EXT_CDEV: {
+		sqfs_inode_dev_ext_t dev = {
+			.nlink = htole32(hard_link_count(node)),
+			.devno = htole32(node->data.devno),
+			.xattr_idx = htole32(0xFFFFFFFF),
+		};
+
+		if (node->xattr != NULL)
+			dev.xattr_idx = htole32(node->xattr->index);
+
+		return meta_writer_append(im, &dev, sizeof(dev));
+	}
+	case SQFS_INODE_EXT_FILE: {
+		file_info_t *fi = node->data.file;
+		sqfs_inode_file_ext_t ext = {
+			.blocks_start = htole64(fi->startblock),
+			.file_size = htole64(fi->size),
+			.sparse = htole64(fi->sparse),
+			.nlink = htole32(hard_link_count(node)),
+			.fragment_idx = htole32(0xFFFFFFFF),
+			.fragment_offset = htole32(0xFFFFFFFF),
+			.xattr_idx = htole32(0xFFFFFFFF),
+		};
+
+		if ((fi->size % fs->block_size) != 0) {
+			ext.fragment_idx = htole32(fi->fragment);
+			ext.fragment_offset = htole32(fi->fragment_offset);
+		}
+
+		if (node->xattr != NULL)
+			ext.xattr_idx = htole32(node->xattr->index);
+
+		if (meta_writer_append(im, &ext, sizeof(ext)))
+			return -1;
+		return write_file_blocks(fs, fi, im);
+	}
+	case SQFS_INODE_FILE: {
+		file_info_t *fi = node->data.file;
+		sqfs_inode_file_t reg = {
+			.blocks_start = htole32(fi->startblock),
+			.fragment_index = htole32(0xFFFFFFFF),
+			.fragment_offset = htole32(0xFFFFFFFF),
+			.file_size = htole32(fi->size),
+		};
+
+		if ((fi->size % fs->block_size) != 0) {
+			reg.fragment_index = htole32(fi->fragment);
+			reg.fragment_offset = htole32(fi->fragment_offset);
+		}
+
+		if (meta_writer_append(im, &reg, sizeof(reg)))
+			return -1;
+		return write_file_blocks(fs, fi, im);
+	}
+	case SQFS_INODE_DIR: {
+		sqfs_inode_dir_t dir = {
+			.start_block = htole32(node->data.dir->start_block),
+			.nlink = htole32(hard_link_count(node)),
+			.size = htole16(node->data.dir->size),
+			.offset = htole16(node->data.dir->block_offset),
+			.parent_inode = node->parent ?
+				htole32(node->parent->inode_num) : htole32(1),
+		};
+
+		return meta_writer_append(im, &dir, sizeof(dir));
+	}
+	case SQFS_INODE_EXT_DIR: {
+		sqfs_inode_dir_ext_t ext = {
+			.nlink = htole32(hard_link_count(node)),
+			.size = htole32(node->data.dir->size),
+			.start_block = htole32(node->data.dir->start_block),
+			.parent_inode = node->parent ?
+				htole32(node->parent->inode_num) : htole32(1),
+			.inodex_count = htole32(0),
+			.offset = htole16(node->data.dir->block_offset),
+			.xattr_idx = htole32(0xFFFFFFFF),
+		};
+
+		if (node->xattr != NULL)
+			ext.xattr_idx = htole32(node->xattr->index);
+
+		if (diridx != NULL)
+			ext.inodex_count = htole32(diridx->num_nodes - 1);
+
+		if (meta_writer_append(im, &ext, sizeof(ext))) {
+			free(diridx);
+			return -1;
+		}
+
+		if (diridx != NULL && write_dir_index(diridx, im) != 0) {
+			free(diridx);
+			return -1;
+		}
+
+		free(diridx);
+		break;
+	}
+	default:
+		assert(0);
+	}
+	return 0;
+}