Add utility to turn a POSIX/PAX tar archive into a squashfs image

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

1 files changed, 267 insertions, 0 deletions

diff --git a/tar/tar2sqfs.c b/tar/tar2sqfs.c
new file mode 100644
index 0000000..f00f281
--- /dev/null
+++ b/tar/tar2sqfs.c
@@ -0,0 +1,267 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+#include "data_writer.h"
+#include "highlevel.h"
+#include "squashfs.h"
+#include "compress.h"
+#include "id_table.h"
+#include "fstree.h"
+#include "util.h"
+#include "tar.h"
+
+#include <sys/sysmacros.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <unistd.h>
+#include <string.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <errno.h>
+#include <fcntl.h>
+
+static struct option long_opts[] = {
+	{ "help", no_argument, NULL, 'h' },
+	{ "version", no_argument, NULL, 'V' },
+};
+
+static const char *short_opts = "hV";
+
+static const char *usagestr =
+"Usage: tar2sqfs [OPTIONS...] <sqfsfile>\n"
+"\n"
+"Read an uncompressed tar archive from stdin and turn it into a squashfs\n"
+"filesystem image.\n"
+"\n"
+"Possible options:\n"
+"\n"
+"  --help, -h                Print help text and exit.\n"
+"  --version, -V             Print version information and exit.\n"
+"\n"
+"Examples:\n"
+"\n"
+"\ttar2sqfs rootfs.sqfs < rootfs.tar\n"
+"\tzcat rootfs.tar.gz | tar2sqfs rootfs.sqfs\n"
+"\txzcat rootfs.tar.xz | tar2sqfs rootfs.sqfs\n"
+"\n";
+
+static const char *filename;
+static int block_size = SQFS_DEFAULT_BLOCK_SIZE;
+static uint32_t def_mtime = 0;
+static uint16_t def_mode = 0755;
+static uint32_t def_uid = 0;
+static uint32_t def_gid = 0;
+static size_t devblksize = SQFS_DEVBLK_SIZE;
+
+static void process_args(int argc, char **argv)
+{
+	int i;
+
+	for (;;) {
+		i = getopt_long(argc, argv, short_opts, long_opts, NULL);
+		if (i == -1)
+			break;
+
+		switch (i) {
+		case 'h':
+			fputs(usagestr, stdout);
+			exit(EXIT_SUCCESS);
+		case 'V':
+			print_version();
+			exit(EXIT_SUCCESS);
+		default:
+			goto fail_arg;
+		}
+	}
+
+	if (optind >= argc) {
+		fputs("Missing argument: squashfs image\n", stderr);
+		goto fail_arg;
+	}
+
+	filename = argv[optind++];
+
+	if (optind < argc) {
+		fputs("Unknown extra arguments\n", stderr);
+		goto fail_arg;
+	}
+	return;
+fail_arg:
+	fputs("Try `tar2sqfs --help' for more information.\n", stderr);
+	exit(EXIT_FAILURE);
+}
+
+static int create_node_and_repack_data(tar_header_decoded_t *hdr, fstree_t *fs,
+				       data_writer_t *data)
+{
+	tree_node_t *node;
+	size_t extra = 0;
+
+	if (S_ISLNK(hdr->mode))
+		extra = strlen(hdr->link_target) + 1;
+
+	if (S_ISREG(hdr->mode)) {
+		node = fstree_add_file(fs, hdr->name, hdr->mode,
+				       hdr->uid, hdr->gid, hdr->size, NULL);
+		if (node == NULL)
+			goto fail_errno;
+
+		if (write_data_from_fd(data, node->data.file,
+				       STDIN_FILENO)) {
+			return -1;
+		}
+
+		if (skip_padding(STDIN_FILENO, node->data.file->size))
+			return -1;
+	} else {
+		node = fstree_add(fs, hdr->name, hdr->mode,
+				  hdr->uid, hdr->gid, extra);
+		if (node == NULL)
+			goto fail_errno;
+
+		if (S_ISLNK(hdr->mode)) {
+			strcpy(node->data.slink_target,
+			       hdr->link_target);
+		} else if (S_ISBLK(hdr->mode) || S_ISCHR(hdr->mode)) {
+			node->data.devno = makedev(hdr->dev_maj, hdr->dev_min);
+		}
+	}
+
+	return 0;
+fail_errno:
+	perror(hdr->name);
+	return -1;
+}
+
+static int process_tar_ball(fstree_t *fs, data_writer_t *data)
+{
+	tar_header_decoded_t hdr;
+	int ret;
+
+	for (;;) {
+		ret = read_header(STDIN_FILENO, &hdr);
+		if (ret > 0)
+			break;
+		if (ret < 0)
+			return -1;
+
+		if (hdr.unknown_record) {
+			fprintf(stderr, "skipping '%s' (unknown entry type)\n",
+				hdr.name);
+			if (skip_entry(STDIN_FILENO, hdr.size))
+				goto fail;
+			continue;
+		}
+
+		if (canonicalize_name(hdr.name)) {
+			fprintf(stderr, "skipping '%s' (invalid name)\n",
+				hdr.name);
+			if (skip_entry(STDIN_FILENO, hdr.size))
+				goto fail;
+			continue;
+		}
+
+		if (create_node_and_repack_data(&hdr, fs, data))
+			goto fail;
+
+		clear_header(&hdr);
+	}
+
+	return 0;
+fail:
+	clear_header(&hdr);
+	return -1;
+}
+
+int main(int argc, char **argv)
+{
+	int outfd, status = EXIT_SUCCESS;
+	E_SQFS_COMPRESSOR comp_id;
+	data_writer_t *data;
+	sqfs_super_t super;
+	compressor_t *cmp;
+	id_table_t idtbl;
+	fstree_t fs;
+	int ret;
+
+	process_args(argc, argv);
+
+	outfd = open(filename, O_CREAT | O_EXCL | O_RDWR, 0644);
+	if (outfd < 0) {
+		perror(filename);
+		return EXIT_FAILURE;
+	}
+
+	if (fstree_init(&fs, block_size, def_mtime, def_mode,
+			def_uid, def_gid)) {
+		goto out_fd;
+	}
+
+	comp_id = compressor_get_default();
+
+	cmp = compressor_create(comp_id, true, block_size, NULL);
+	if (cmp == NULL) {
+		fputs("Error creating compressor\n", stderr);
+		goto out_fs;
+	}
+
+	if (sqfs_super_init(&super, block_size, def_mtime, comp_id))
+		goto out_cmp;
+
+	if (sqfs_super_write(&super, outfd))
+		goto out_cmp;
+
+	ret = cmp->write_options(cmp, outfd);
+	if (ret < 0)
+		goto out_cmp;
+
+	if (ret > 0) {
+		super.flags |= SQFS_FLAG_COMPRESSOR_OPTIONS;
+		super.bytes_used += ret;
+	}
+
+	data = data_writer_create(&super, cmp, outfd);
+	if (data == NULL)
+		goto out_cmp;
+
+	if (id_table_init(&idtbl))
+		goto out_data;
+
+	if (process_tar_ball(&fs, data))
+		goto out;
+
+	if (data_writer_flush_fragments(data))
+		goto out;
+
+	fstree_sort(&fs);
+	if (fstree_gen_inode_table(&fs))
+		goto out;
+
+	super.inode_count = fs.inode_tbl_size - 2;
+
+	if (sqfs_serialize_fstree(outfd, &super, &fs, cmp, &idtbl))
+		goto out;
+
+	if (data_writer_write_fragment_table(data))
+		goto out;
+
+	if (id_table_write(&idtbl, outfd, &super, cmp))
+		goto out;
+
+	if (sqfs_super_write(&super, outfd))
+		goto out;
+
+	if (padd_file(outfd, super.bytes_used, devblksize))
+		goto out;
+
+	status = EXIT_SUCCESS;
+out:
+	id_table_cleanup(&idtbl);
+out_data:
+	data_writer_destroy(data);
+out_cmp:
+	cmp->destroy(cmp);
+out_fs:
+	fstree_cleanup(&fs);
+out_fd:
+	close(outfd);
+	return status;
+}