cleanup: move entire fstree serialization to libsqfs.a

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

4 files changed, 521 insertions, 0 deletions

diff --git a/lib/Makemodule.am b/lib/Makemodule.am
index 536cad0..bf4ed61 100644
--- a/lib/Makemodule.am
+++ b/lib/Makemodule.am
@@ -17,6 +17,8 @@ libsquashfs_a_SOURCES += lib/sqfs/read_super.c lib/sqfs/meta_reader.c
 libsquashfs_a_SOURCES += include/meta_reader.h lib/sqfs/id_table_write.c
 libsquashfs_a_SOURCES += lib/sqfs/id_table_read.c lib/sqfs/read_inode.c
 libsquashfs_a_SOURCES += lib/sqfs/readdir.c lib/sqfs/frag_reader.c
+libsquashfs_a_SOURCES += lib/sqfs/write_dir.c lib/sqfs/write_inode.c
+libsquashfs_a_SOURCES += lib/sqfs/serialize_fstree.c
 libsquashfs_a_SOURCES += include/frag_reader.h
 
 libutil_a_SOURCES = lib/util/canonicalize_name.c lib/util/write_retry.c
diff --git a/lib/sqfs/serialize_fstree.c b/lib/sqfs/serialize_fstree.c
new file mode 100644
index 0000000..95b9144
--- /dev/null
+++ b/lib/sqfs/serialize_fstree.c
@@ -0,0 +1,100 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+#include "meta_writer.h"
+#include "table.h"
+#include "util.h"
+
+#include <unistd.h>
+#include <stdio.h>
+
+int sqfs_serialize_fstree(int outfd, sqfs_super_t *super, fstree_t *fs,
+			  compressor_t *cmp, id_table_t *idtbl)
+{
+	meta_writer_t *im, *dm;
+	uint8_t buffer[1024];
+	uint32_t offset;
+	uint64_t block;
+	size_t i, diff;
+	ssize_t ret;
+	FILE *tmp;
+	int tmpfd;
+
+	tmp = tmpfile();
+	if (tmp == NULL) {
+		perror("tmpfile");
+		return -1;
+	}
+
+	tmpfd = fileno(tmp);
+
+	im = meta_writer_create(outfd, cmp);
+	if (im == NULL)
+		goto fail_tmp;
+
+	dm = meta_writer_create(tmpfd, cmp);
+	if (dm == NULL)
+		goto fail_im;
+
+	for (i = 2; i < fs->inode_tbl_size; ++i) {
+		if (meta_writer_write_inode(fs, idtbl, im, dm,
+					    fs->inode_table[i])) {
+			goto fail;
+		}
+	}
+
+	if (meta_writer_flush(im))
+		goto fail;
+
+	if (meta_writer_flush(dm))
+		goto fail;
+
+	super->root_inode_ref = fs->root->inode_ref;
+
+	meta_writer_get_position(im, &block, &offset);
+	super->inode_table_start = super->bytes_used;
+	super->bytes_used += block;
+
+	super->directory_table_start = super->bytes_used;
+	meta_writer_get_position(dm, &block, &offset);
+	super->bytes_used += block;
+
+	if (lseek(tmpfd, 0, SEEK_SET) == (off_t)-1) {
+		perror("rewind on directory temp file");
+		goto fail;
+	}
+
+	for (;;) {
+		ret = read_retry(tmpfd, buffer, sizeof(buffer));
+
+		if (ret < 0) {
+			perror("read from temp file");
+			goto fail;
+		}
+		if (ret == 0)
+			break;
+
+		diff = ret;
+		ret = write_retry(outfd, buffer, diff);
+
+		if (ret < 0) {
+			perror("write to image file");
+			goto fail;
+		}
+		if ((size_t)ret < diff) {
+			fputs("copying meta data to image file: "
+			      "truncated write\n", stderr);
+			goto fail;
+		}
+	}
+
+	meta_writer_destroy(dm);
+	meta_writer_destroy(im);
+	fclose(tmp);
+	return 0;
+fail:
+	meta_writer_destroy(dm);
+fail_im:
+	meta_writer_destroy(im);
+fail_tmp:
+	fclose(tmp);
+	return -1;
+}
diff --git a/lib/sqfs/write_dir.c b/lib/sqfs/write_dir.c
new file mode 100644
index 0000000..b334864
--- /dev/null
+++ b/lib/sqfs/write_dir.c
@@ -0,0 +1,127 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+#include "meta_writer.h"
+#include "util.h"
+
+#include <assert.h>
+#include <endian.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+static int get_type(mode_t mode)
+{
+	switch (mode & S_IFMT) {
+	case S_IFSOCK: return SQFS_INODE_SOCKET;
+	case S_IFIFO:  return SQFS_INODE_FIFO;
+	case S_IFLNK:  return SQFS_INODE_SLINK;
+	case S_IFBLK:  return SQFS_INODE_BDEV;
+	case S_IFCHR:  return SQFS_INODE_CDEV;
+	case S_IFDIR:  return SQFS_INODE_DIR;
+	case S_IFREG:  return SQFS_INODE_FILE;
+	default:
+		assert(0);
+	}
+}
+
+static int dir_index_grow(dir_index_t **index)
+{
+	size_t size = sizeof(dir_index_t) + sizeof(idx_ref_t) * 10;
+	void *new;
+
+	if (*index == NULL) {
+		new = calloc(1, size);
+	} else {
+		if ((*index)->num_nodes < (*index)->max_nodes)
+			return 0;
+
+		size += sizeof(idx_ref_t) * (*index)->num_nodes;
+		new = realloc(*index, size);
+	}
+
+	if (new == NULL) {
+		perror("creating directory index");
+		return -1;
+	}
+
+	*index = new;
+	(*index)->max_nodes += 10;
+	return 0;
+}
+
+int meta_writer_write_dir(meta_writer_t *dm, dir_info_t *dir,
+			  dir_index_t **index)
+{
+	size_t i, size, count;
+	sqfs_dir_header_t hdr;
+	sqfs_dir_entry_t ent;
+	tree_node_t *c, *d;
+	uint32_t offset;
+	uint64_t block;
+
+	c = dir->children;
+	dir->size = 0;
+
+	meta_writer_get_position(dm, &dir->start_block, &dir->block_offset);
+
+	while (c != NULL) {
+		meta_writer_get_position(dm, &block, &offset);
+
+		count = 0;
+		size = (offset + sizeof(hdr)) % SQFS_META_BLOCK_SIZE;
+
+		for (d = c; d != NULL; d = d->next) {
+			if ((d->inode_ref >> 16) != (c->inode_ref >> 16))
+				break;
+
+			/* XXX: difference is actually signed */
+			if ((d->inode_num - c->inode_num) > 0x7FFF)
+				break;
+
+			size += sizeof(ent) + strlen(c->name);
+
+			if (count > 0 && size > SQFS_META_BLOCK_SIZE)
+				break;
+
+			count += 1;
+		}
+
+		if (count > SQFS_MAX_DIR_ENT)
+			count = SQFS_MAX_DIR_ENT;
+
+		if (dir_index_grow(index))
+			return -1;
+
+		meta_writer_get_position(dm, &block, &offset);
+
+		i = (*index)->num_nodes++;
+		(*index)->idx_nodes[i].node = c;
+		(*index)->idx_nodes[i].block = block;
+		(*index)->idx_nodes[i].offset = offset;
+
+		hdr.count = htole32(count - 1);
+		hdr.start_block = htole32(c->inode_ref >> 16);
+		hdr.inode_number = htole32(c->inode_num);
+		dir->size += sizeof(hdr);
+
+		if (meta_writer_append(dm, &hdr, sizeof(hdr)))
+			return -1;
+
+		d = c;
+
+		for (i = 0; i < count; ++i) {
+			ent.offset = htole16(c->inode_ref & 0x0000FFFF);
+			ent.inode_number = htole16(c->inode_num - d->inode_num);
+			ent.type = htole16(get_type(c->mode));
+			ent.size = htole16(strlen(c->name) - 1);
+			dir->size += sizeof(ent) + strlen(c->name);
+
+			if (meta_writer_append(dm, &ent, sizeof(ent)))
+				return -1;
+			if (meta_writer_append(dm, c->name, strlen(c->name)))
+				return -1;
+
+			c = c->next;
+		}
+	}
+	return 0;
+}
diff --git a/lib/sqfs/write_inode.c b/lib/sqfs/write_inode.c
new file mode 100644
index 0000000..961013c
--- /dev/null
+++ b/lib/sqfs/write_inode.c
@@ -0,0 +1,292 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+#include "meta_writer.h"
+#include "util.h"
+
+#include <assert.h>
+#include <endian.h>
+#include <stdlib.h>
+#include <string.h>
+
+static int get_type(tree_node_t *node)
+{
+	int type;
+
+	switch (node->mode & S_IFMT) {
+	case S_IFSOCK: type = SQFS_INODE_SOCKET; break;
+	case S_IFIFO:  type = SQFS_INODE_FIFO; break;
+	case S_IFLNK:  type = SQFS_INODE_SLINK; break;
+	case S_IFBLK:  type = SQFS_INODE_BDEV; break;
+	case S_IFCHR:  type = SQFS_INODE_CDEV; break;
+	case S_IFDIR:  type = SQFS_INODE_DIR; break;
+	case S_IFREG:  type = SQFS_INODE_FILE; break;
+	default:
+		assert(0);
+	}
+
+	if (node->xattr != NULL)
+		type = SQFS_INODE_EXT_TYPE(type);
+
+	return type;
+}
+
+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;
+}
+
+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;
+	file_info_t *fi = NULL;
+	dir_info_t *di = NULL;
+	uint32_t bs, offset;
+	sqfs_inode_t base;
+	uint64_t i, block;
+	int type;
+
+	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;
+
+	type = get_type(node);
+
+	if (S_ISDIR(node->mode)) {
+		di = node->data.dir;
+
+		if (meta_writer_write_dir(dm, di, &diridx))
+			return -1;
+
+		if ((di->start_block) > 0xFFFFFFFFUL || di->size > 0xFFFF ||
+		    node->xattr != NULL) {
+			type = SQFS_INODE_EXT_DIR;
+		} else {
+			type = SQFS_INODE_DIR;
+			free(diridx);
+			diridx = NULL;
+		}
+	} else if (S_ISREG(node->mode)) {
+		fi = node->data.file;
+
+		if (fi->startblock > 0xFFFFFFFFUL || fi->size > 0xFFFFFFFFUL ||
+		    hard_link_count(node) > 1) {
+			type = SQFS_INODE_EXT_FILE;
+		}
+	}
+
+	base.type = htole16(type);
+	base.mode = htole16(node->mode);
+	base.uid_idx = htole16(uid_idx);
+	base.gid_idx = htole16(gid_idx);
+	base.mod_time = htole32(fs->default_mtime);
+	base.inode_number = htole32(node->inode_num);
+
+	if (meta_writer_append(im, &base, sizeof(base))) {
+		free(diridx);
+		return -1;
+	}
+
+	switch (type) {
+	case SQFS_INODE_FIFO:
+	case SQFS_INODE_SOCKET: {
+		sqfs_inode_ipc_t ipc = {
+			.nlink = 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 = 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: {
+		sqfs_inode_file_ext_t ext = {
+			.blocks_start = htole64(fi->startblock),
+			.file_size = htole64(fi->size),
+			.sparse = htole64(0xFFFFFFFFFFFFFFFFUL),
+			.nlink = htole32(hard_link_count(node)),
+			.fragment_idx = htole32(fi->fragment),
+			.fragment_offset = htole32(fi->fragment_offset),
+			.xattr_idx = htole32(0xFFFFFFFF),
+		};
+
+		if (node->xattr != NULL)
+			ext.xattr_idx = htole32(node->xattr->index);
+
+		if (meta_writer_append(im, &ext, sizeof(ext)))
+			return -1;
+		goto out_file_blocks;
+	}
+	case SQFS_INODE_FILE: {
+		sqfs_inode_file_t reg = {
+			.blocks_start = htole32(fi->startblock),
+			.fragment_index = htole32(fi->fragment),
+			.fragment_offset = htole32(fi->fragment_offset),
+			.file_size = htole32(fi->size),
+		};
+
+		if (meta_writer_append(im, &reg, sizeof(reg)))
+			return -1;
+		goto out_file_blocks;
+	}
+	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_dir_index_t idx;
+		size_t i;
+		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 (meta_writer_append(im, &ext, sizeof(ext))) {
+			free(diridx);
+			return -1;
+		}
+
+		/* HACK: truncated index for empty directories */
+		if (node->data.dir->size == 0)
+			break;
+
+		ext.inodex_count = htole32(diridx->num_nodes - 1);
+
+		for (i = 0; i < diridx->num_nodes; ++i) {
+			idx.start_block = htole32(diridx->idx_nodes[i].block);
+
+			idx.index = diridx->idx_nodes[i].offset;
+			idx.index -= node->data.dir->block_offset;
+			idx.index = htole32(idx.index);
+
+			idx.size = strlen(diridx->idx_nodes[i].node->name) - 1;
+			idx.size = htole32(idx.size);
+
+			if (meta_writer_append(im, &idx, sizeof(idx))) {
+				free(diridx);
+				return -1;
+			}
+
+			if (meta_writer_append(im,
+					       diridx->idx_nodes[i].node->name,
+					       le32toh(idx.size) + 1)) {
+				free(diridx);
+				return -1;
+			}
+		}
+
+		free(diridx);
+		break;
+	}
+	default:
+		assert(0);
+	}
+	return 0;
+out_file_blocks:
+	for (i = 0; i < fi->size / fs->block_size; ++i) {
+		bs = htole32(fi->blocksizes[i]);
+
+		if (meta_writer_append(im, &bs, sizeof(bs)))
+			return -1;
+	}
+	return 0;
+}