Implement snbk snapshot metadata update

client/snbk/BackupConfig.cc

@@ -76,6 +76,7 @@ namespace snapper
 	get_child_value(json_file.get_root(), "target-mkdir-bin", target_mkdir_bin);
 	get_child_value(json_file.get_root(), "target-rm-bin", target_rm_bin);
 	get_child_value(json_file.get_root(), "target-rmdir-bin", target_rmdir_bin);
+	get_child_value(json_file.get_root(), "target-sha256sum-bin", target_sha256sum_bin);
     }
 
 

client/snbk/BackupConfig.h

@@ -78,6 +78,7 @@ namespace snapper
 	string target_mkdir_bin = MKDIR_BIN;
 	string target_rm_bin = RM_BIN;
 	string target_rmdir_bin = RMDIR_BIN;
+	string target_sha256sum_bin = SHA256SUM_BIN;
 
     private:
 

client/snbk/CmdMetaHash.cc

@@ -0,0 +1,125 @@
+/*
+ * Copyright (c) 2026 SUSE LLC
+ *
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, contact Novell, Inc.
+ *
+ * To contact Novell about this file by physical or electronic mail, you may
+ * find current contact information at www.novell.com.
+ */
+
+
+#include <boost/algorithm/string.hpp>
+
+#include <snapper/AppUtil.h>
+#include <snapper/Exception.h>
+#include <snapper/LoggerImpl.h>
+#include <snapper/SnapperDefines.h>
+#include <snapper/SystemCmd.h>
+
+#include "../utils/text.h"
+
+#include "CmdMetaHash.h"
+
+
+namespace snapper
+{
+
+    CmdMetaHash::CmdMetaHash(const Shell& shell, const string& chksum_bin,
+                             const string& sh_bin, const string& path)
+        : path(path)
+    {
+	SystemCmd::Args cmd_args = {
+	    sh_bin, "-c",
+	    sformat("for d in $(ls -1 %s); do %s %s/$d/info.xml; done", path.c_str(),
+	            chksum_bin.c_str(), path.c_str())
+	};
+	SystemCmd cmd(shellify(shell, cmd_args));
+
+	if (cmd.retcode() != 0)
+	{
+	    y2err("command '" << cmd.cmd() << "' failed: " << cmd.retcode());
+	    for (const string& tmp : cmd.get_stdout())
+		y2err(tmp);
+	    for (const string& tmp : cmd.get_stderr())
+		y2err(tmp);
+
+	    SN_THROW(Exception(_("Hashing for snapshot metadata failed.")));
+	}
+
+	parse(cmd.get_stdout());
+
+	y2mil(*this);
+    }
+
+
+    const string& CmdMetaHash::get_hash(unsigned int num) const
+    {
+	auto pair = lookup.find(num);
+	if (pair == lookup.end())
+	{
+	    string error = sformat(_("Meta hash of snapshot %d not found."), num);
+	    SN_THROW(Exception(error));
+	}
+
+	return pair->second;
+    }
+
+
+    void CmdMetaHash::parse(const vector<string>& lines)
+    {
+	for (const string& line : lines)
+	{
+	    // Extract the hash and the path
+	    vector<string> parts;
+	    boost::split(parts, line, boost::is_any_of(" "), boost::token_compress_on);
+	    if (parts.size() != 2)
+	    {
+		y2err("Invalid hash string: " << line);
+		SN_THROW(Exception(_("Invalid hash output format.")));
+	    }
+
+	    const string& hash = parts.front();
+	    const string& path = parts.back();
+
+	    // Split the path into components
+	    vector<string> comps;
+	    boost::split(comps, path, boost::is_any_of("/"), boost::token_compress_on);
+	    if (comps.size() < 2)
+	    {
+		SN_THROW(Exception(_("Unexpected path format.")));
+	    }
+
+	    // Convert the snapshot number (second‑to‑last component)
+	    unsigned int num = stoi(comps[comps.size() - 2]);
+
+	    // Store the hash
+	    lookup[num] = hash;
+	}
+    }
+
+
+    std::ostream& operator<<(std::ostream& s, const CmdMetaHash& cmd_metahash)
+    {
+	s << "path: " << cmd_metahash.path << '\n';
+	for (const auto& [num, hash] : cmd_metahash.lookup)
+	{
+	    s << sformat("  num: %d, hash: %s\n", num, hash.c_str());
+	}
+
+	return s;
+    }
+
+
+} // namespace snapper

client/snbk/CmdMetaHash.h

@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2026 SUSE LLC
+ *
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, contact Novell, Inc.
+ *
+ * To contact Novell about this file by physical or electronic mail, you may
+ * find current contact information at www.novell.com.
+ */
+
+
+#ifndef SNAPPER_CMD_META_HASH_H
+#define SNAPPER_CMD_META_HASH_H
+
+
+#include <map>
+
+#include "Shell.h"
+
+
+namespace snapper
+{
+    using std::string;
+
+
+    /**
+     * Find the hashes (by checksum) of info.xml for all snapshots.
+     */
+    class CmdMetaHash
+    {
+    public:
+
+	CmdMetaHash(const Shell& shell, const string& chksum_bin, const string& sh_bin,
+	            const string& path);
+
+	const string& get_hash(unsigned int num) const;
+
+	friend std::ostream& operator<<(std::ostream& s, const CmdMetaHash& cmd_metahash);
+
+    private:
+
+	const string path;
+
+	std::map<unsigned int, string> lookup;
+
+	void parse(const std::vector<string>& lines);
+    };
+
+} // namespace snapper
+
+
+#endif

client/snbk/Makefile.am

@@ -22,6 +22,7 @@ snbk_SOURCES = 						\
 	Shell.cc		Shell.h			\
 	CmdBtrfs.cc		CmdBtrfs.h		\
 	CmdLs.cc		CmdLs.h			\
+	CmdMetaHash.cc		CmdMetaHash.h		\
 	JsonFile.cc		JsonFile.h		\
 	utils.cc		utils.h			\
 	TreeView.cc		TreeView.h