diff --git a/src/libslic3r/AppConfig.cpp b/src/libslic3r/AppConfig.cpp
index 7c9403382..6d588075d 100644
--- a/src/libslic3r/AppConfig.cpp
+++ b/src/libslic3r/AppConfig.cpp
@@ -3,6 +3,7 @@
#include "AppConfig.hpp"
#include "Exception.hpp"
#include "Thread.hpp"
+#include "format.hpp"
#include <utility>
#include <vector>
@@ -16,9 +17,13 @@
#include <boost/property_tree/ptree_fwd.hpp>
#include <boost/algorithm/string/predicate.hpp>
#include <boost/format/format_fwd.hpp>
+#include <boost/log/trivial.hpp>
-//#include <wx/string.h>
-//#include "I18N.hpp"
+#ifdef WIN32
+//FIXME replace the two following includes with <boost/md5.hpp> after it becomes mainstream.
+#include <boost/uuid/detail/md5.hpp>
+#include <boost/algorithm/hex.hpp>
+#endif
namespace Slic3r {
@@ -164,25 +169,114 @@ void AppConfig::set_defaults()
erase("", "object_settings_size");
}
+#ifdef WIN32
+static std::string appconfig_md5_hash_line(const std::string_view data)
+{
+ //FIXME replace the two following includes with <boost/md5.hpp> after it becomes mainstream.
+ // return boost::md5(data).hex_str_value();
+ // boost::uuids::detail::md5 is an internal namespace thus it may change in the future.
+ // Also this implementation is not the fastest, it was designed for short blocks of text.
+ using boost::uuids::detail::md5;
+ md5 md5_hash;
+ // unsigned int[4], 128 bits
+ md5::digest_type md5_digest{};
+ std::string md5_digest_str;
+ md5_hash.process_bytes(data.data(), data.size());
+ md5_hash.get_digest(md5_digest);
+ boost::algorithm::hex(md5_digest, md5_digest + std::size(md5_digest), std::back_inserter(md5_digest_str));
+ // MD5 hash is 32 HEX digits long.
+ assert(md5_digest_str.size() == 32);
+ // This line will be emited at the end of the file.
+ return "# MD5 checksum " + md5_digest_str + "\n";
+};
+
+// Assume that the last line with the comment inside the config file contains a checksum and that the user didn't modify the config file.
+static bool verify_config_file_checksum(boost::nowide::ifstream &ifs)
+{
+ auto read_whole_config_file = [&ifs]() -> std::string {
+ std::stringstream ss;
+ ss << ifs.rdbuf();
+ return ss.str();
+ };
+
+ ifs.seekg(0, boost::nowide::ifstream::beg);
+ std::string whole_config = read_whole_config_file();
+
+ // The checksum should be on the last line in the config file.
+ if (size_t last_comment_pos = whole_config.find_last_of('#'); last_comment_pos != std::string::npos) {
+ // Split read config into two parts, one with checksum, and the second part is part with configuration from the checksum was computed.
+ // Verify existence and validity of the MD5 checksum line at the end of the file.
+ // When the checksum isn't found, the checksum was not saved correctly, it was removed or it is an older config file without the checksum.
+ // If the checksum is incorrect, then the file was either not saved correctly or modified.
+ if (std::string_view(whole_config.c_str() + last_comment_pos, whole_config.size() - last_comment_pos) == appconfig_md5_hash_line({ whole_config.data(), last_comment_pos }))
+ return true;
+ }
+ return false;
+}
+#endif
+
std::string AppConfig::load()
{
// 1) Read the complete config file into a boost::property_tree.
namespace pt = boost::property_tree;
pt::ptree tree;
- boost::nowide::ifstream ifs(AppConfig::config_path());
+ boost::nowide::ifstream ifs;
+ bool recovered = false;
+
try {
+ ifs.open(AppConfig::config_path());
+#ifdef WIN32
+ // Verify the checksum of the config file without taking just for debugging purpose.
+ if (!verify_config_file_checksum(ifs))
+ BOOST_LOG_TRIVIAL(info) << "The configuration file " << AppConfig::config_path() <<
+ " has a wrong MD5 checksum or the checksum is missing. This may indicate a file corruption or a harmless user edit.";
+
+ ifs.seekg(0, boost::nowide::ifstream::beg);
+#endif
pt::read_ini(ifs, tree);
} catch (pt::ptree_error& ex) {
- // Error while parsing config file. We'll customize the error message and rethrow to be displayed.
- // ! But to avoid the use of _utf8 (related to use of wxWidgets)
- // we will rethrow this exception from the place of load() call, if returned value wouldn't be empty
- /*
- throw Slic3r::RuntimeError(
- _utf8(L("Error parsing PrusaSlicer config file, it is probably corrupted. "
- "Try to manually delete the file to recover from the error. Your user profiles will not be affected.")) +
- "\n\n" + AppConfig::config_path() + "\n\n" + ex.what());
- */
- return ex.what();
+#ifdef WIN32
+ // The configuration file is corrupted, try replacing it with the backup configuration.
+ ifs.close();
+ std::string backup_path = (boost::format("%1%.bak") % AppConfig::config_path()).str();
+ if (boost::filesystem::exists(backup_path)) {
+ // Compute checksum of the configuration backup file and try to load configuration from it when the checksum is correct.
+ boost::nowide::ifstream backup_ifs(backup_path);
+ if (!verify_config_file_checksum(backup_ifs)) {
+ BOOST_LOG_TRIVIAL(error) << format("Both \"%1%\" and \"%2%\" are corrupted. It isn't possible to restore configuration from the backup.", AppConfig::config_path(), backup_path);
+ backup_ifs.close();
+ boost::filesystem::remove(backup_path);
+ } else if (std::string error_message; copy_file(backup_path, AppConfig::config_path(), error_message, false) != SUCCESS) {
+ BOOST_LOG_TRIVIAL(error) << format("Configuration file \"%1%\" is corrupted. Failed to restore from backup \"%2%\": %3%", AppConfig::config_path(), backup_path, error_message);
+ backup_ifs.close();
+ boost::filesystem::remove(backup_path);
+ } else {
+ BOOST_LOG_TRIVIAL(info) << format("Configuration file \"%1%\" was corrupted. It has been succesfully restored from the backup \"%2%\".", AppConfig::config_path(), backup_path);
+ // Try parse configuration file after restore from backup.
+ try {
+ ifs.open(AppConfig::config_path());
+ pt::read_ini(ifs, tree);
+ recovered = true;
+ } catch (pt::ptree_error& ex) {
+ BOOST_LOG_TRIVIAL(info) << format("Failed to parse configuration file \"%1%\" after it has been restored from backup: %2%", AppConfig::config_path(), ex.what());
+ }
+ }
+ } else
+#endif // WIN32
+ BOOST_LOG_TRIVIAL(info) << format("Failed to parse configuration file \"%1%\": %2%", AppConfig::config_path(), ex.what());
+ if (! recovered) {
+ // Report the initial error of parsing PrusaSlicer.ini.
+ // Error while parsing config file. We'll customize the error message and rethrow to be displayed.
+ // ! But to avoid the use of _utf8 (related to use of wxWidgets)
+ // we will rethrow this exception from the place of load() call, if returned value wouldn't be empty
+ /*
+ throw Slic3r::RuntimeError(
+ _utf8(L("Error parsing PrusaSlicer config file, it is probably corrupted. "
+ "Try to manually delete the file to recover from the error. Your user profiles will not be affected.")) +
+ "\n\n" + AppConfig::config_path() + "\n\n" + ex.what());
+ */
+ return ex.what();
+ }
}
// 2) Parse the property_tree, extract the sections and key / value pairs.
@@ -259,22 +353,21 @@ void AppConfig::save()
const auto path = config_path();
std::string path_pid = (boost::format("%1%.%2%") % path % get_current_pid()).str();
- boost::nowide::ofstream c;
- c.open(path_pid, std::ios::out | std::ios::trunc);
+ std::stringstream config_ss;
if (m_mode == EAppMode::Editor)
- c << "# " << Slic3r::header_slic3r_generated() << std::endl;
+ config_ss << "# " << Slic3r::header_slic3r_generated() << std::endl;
else
- c << "# " << Slic3r::header_gcodeviewer_generated() << std::endl;
+ config_ss << "# " << Slic3r::header_gcodeviewer_generated() << std::endl;
// Make sure the "no" category is written first.
- for (const std::pair<std::string, std::string> &kvp : m_storage[""])
- c << kvp.first << " = " << kvp.second << std::endl;
+ for (const auto& kvp : m_storage[""])
+ config_ss << kvp.first << " = " << kvp.second << std::endl;
// Write the other categories.
for (const auto category : m_storage) {
if (category.first.empty())
continue;
- c << std::endl << "[" << category.first << "]" << std::endl;
- for (const std::pair<std::string, std::string> &kvp : category.second)
- c << kvp.first << " = " << kvp.second << std::endl;
+ config_ss << std::endl << "[" << category.first << "]" << std::endl;
+ for (const auto& kvp : category.second)
+ config_ss << kvp.first << " = " << kvp.second << std::endl;
}
// Write vendor sections
for (const auto &vendor : m_vendors) {
@@ -282,17 +375,42 @@ void AppConfig::save()
for (const auto &model : vendor.second) { size_sum += model.second.size(); }
if (size_sum == 0) { continue; }
- c << std::endl << "[" << VENDOR_PREFIX << vendor.first << "]" << std::endl;
+ config_ss << std::endl << "[" << VENDOR_PREFIX << vendor.first << "]" << std::endl;
for (const auto &model : vendor.second) {
- if (model.second.size() == 0) { continue; }
+ if (model.second.empty()) { continue; }
const std::vector<std::string> variants(model.second.begin(), model.second.end());
const auto escaped = escape_strings_cstyle(variants);
- c << MODEL_PREFIX << model.first << " = " << escaped << std::endl;
+ config_ss << MODEL_PREFIX << model.first << " = " << escaped << std::endl;
}
}
- c.close();
+ // One empty line before the MD5 sum.
+ config_ss << std::endl;
+ std::string config_str = config_ss.str();
+ boost::nowide::ofstream c;
+ c.open(path_pid, std::ios::out | std::ios::trunc);
+ c << config_str;
+#ifdef WIN32
+ // WIN32 specific: The final "rename_file()" call is not safe in case of an application crash, there is no atomic "rename file" API
+ // provided by Windows (sic!). Therefore we save a MD5 checksum to be able to verify file corruption. In addition,
+ // we save the config file into a backup first before moving it to the final destination.
+ c << appconfig_md5_hash_line(config_str);
+#endif
+ c.close();
+
+#ifdef WIN32
+ // Make a backup of the configuration file before copying it to the final destination.
+ std::string error_message;
+ std::string backup_path = (boost::format("%1%.bak") % path).str();
+ // Copy configuration file with PID suffix into the configuration file with "bak" suffix.
+ if (copy_file(path_pid, backup_path, error_message, false) != SUCCESS)
+ BOOST_LOG_TRIVIAL(error) << "Copying from " << path_pid << " to " << backup_path << " failed. Failed to create a backup configuration.";
+#endif
+
+ // Rename the config atomically.
+ // On Windows, the rename is likely NOT atomic, thus it may fail if PrusaSlicer crashes on another thread in the meanwhile.
+ // To cope with that, we already made a backup of the config on Windows.
rename_file(path_pid, path);
m_dirty = false;
}
diff --git a/src/libslic3r/AppConfig.hpp b/src/libslic3r/AppConfig.hpp
index c8ccd18cd..0a53a5330 100644
--- a/src/libslic3r/AppConfig.hpp
+++ b/src/libslic3r/AppConfig.hpp
@@ -37,7 +37,7 @@ public:
// Load the slic3r.ini from a user profile directory (or a datadir, if configured).
// return error string or empty strinf
- std::string load();
+ std::string load();
// Store the slic3r.ini into a user profile directory (or a datadir, if configured).
void save();