Crash fix - make path on the fly

Newer versions of gcc have a small string optimizations that makes
moving FileRecordData objects behave incorrectly. When a small string is
moved, string_refs into it become invalid. Making a path on the fly
using the path() method also has the side effect of making
FileRecordData smaller in size.

include/dindexer-machinery/recorddata.hpp

@@ -39,11 +39,11 @@ namespace mchlib {
 			mime_full(),
 			atime(parATime),
 			mtime(parMTime),
-			path(abs_path),
 			mime_type(),
 			mime_charset(),
 			size(0),
 			level(parLevel),
+			path_offset(0),
 			is_directory(parIsDir),
 			is_symlink(parIsSymLink),
 			unreadable(false),
@@ -51,22 +51,23 @@ namespace mchlib {
 		{
 		}
 
-		FileRecordData ( std::string&& parPath, std::size_t parRelPathOffs, std::time_t parATime, std::time_t parMTime, uint16_t parLevel, bool parIsDir, bool parIsSymLink ) :
+		FileRecordData ( std::string&& parPath, uint16_t parRelPathOffs, std::time_t parATime, std::time_t parMTime, uint16_t parLevel, bool parIsDir, bool parIsSymLink ) :
 			hash {},
 			abs_path(std::move(parPath)),
 			mime_full(),
 			atime(parATime),
 			mtime(parMTime),
-			path(boost::string_ref(abs_path).substr(parRelPathOffs)),
 			mime_type(),
 			mime_charset(),
 			size(0),
 			level(parLevel),
+			path_offset(parRelPathOffs),
 			is_directory(parIsDir),
 			is_symlink(parIsSymLink),
 			unreadable(false),
 			hash_valid(false)
 	{
+		assert(path_offset <= abs_path.size());
 	}
 
 #if defined(NDEBUG)
@@ -81,16 +82,18 @@ namespace mchlib {
 		bool operator== ( const FileRecordData& parOther ) const;
 #endif
 
+		boost::string_ref path ( void ) const { return boost::string_ref(abs_path).substr(path_offset); }
+
 		TigerHash hash;
 		std::string abs_path;
 		mime_string mime_full;
 		std::time_t atime;
 		std::time_t mtime;
-		boost::string_ref path;
 		boost::string_ref mime_type;
 		boost::string_ref mime_charset;
 		uint64_t size;
 		uint16_t level;
+		uint16_t path_offset; //Relative path starting character into abs_path
 		bool is_directory;
 		bool is_symlink;
 		bool unreadable;

src/machinery/globbing.cpp

@@ -24,14 +24,14 @@
 namespace mchlib {
 	namespace implem {
 		bool glob_matches (const FileRecordData& parData, const char* parGlob) {
-			assert(parData.path.data());
+			assert(parData.path().data());
 			//assert that the substring in path terminates at the same place
 			//where the one in abs_path terminates (ie: it's null-terminated).
-			assert(parData.path == std::string(parData.path.data()));
+			assert(parData.path() == std::string(parData.path().data()));
 
 			//See https://github.com/FlibbleMr/neolib/blob/master/include/neolib/string_utils.hpp
 			//for an alternative to fnmatch() (grep wildcard_match)
-			const int match = fnmatch(parGlob, parData.path.data(), FNM_PATHNAME);
+			const int match = fnmatch(parGlob, parData.path().data(), FNM_PATHNAME);
 			return not match;
 		}
 	} //namespace implem

src/machinery/scantask/hashing.cpp

@@ -69,7 +69,7 @@ namespace mchlib {
 			for (auto it = parList.begin(); it != parList.end(); ++it) {
 				assert(PathName(parEntry.abs_path) == PathName(it->abs_path).pop_right());
 
-				PathName curr_path(it->path);
+				PathName curr_path(it->path());
 				const auto basename = mchlib::basename(curr_path);
 				if (it->is_directory) {
 					auto cd_list = MutableSetListingView(it);

src/machinery/set_listing.cpp

@@ -99,14 +99,14 @@ namespace mchlib {
 		{
 			assert(parBasePath);
 			assert(m_base_path or m_current == m_end);
-			assert(m_current == m_end or m_base_path->atom_count() == PathName(m_current->path).atom_count() + parLevelOffset);
+			assert(m_current == m_end or m_base_path->atom_count() == PathName(m_current->path()).atom_count() + parLevelOffset);
 			assert(m_current == m_end or m_base_path->atom_count() == m_current->level + m_level_offset);
 
 			//Look for the point where the children of this entry start
 			while (
 				m_current != m_end and (
 					m_current->level + m_level_offset == m_base_path->atom_count() or
-					*m_base_path != PathName(m_current->path).pop_right()
+					*m_base_path != PathName(m_current->path()).pop_right()
 			)) {
 				assert(m_base_path);
 				++m_current;
@@ -157,13 +157,13 @@ namespace mchlib {
 
 		template <bool Const>
 		void DirIterator<Const>::increment() {
-			assert(PathName(m_current->path).pop_right() == *m_base_path);
+			assert(PathName(m_current->path()).pop_right() == *m_base_path);
 			do {
 				++m_current;
 			} while(
 				m_current != m_end and
 				m_current->level + m_level_offset == m_base_path->atom_count() + 1 and
-				*m_base_path != PathName(m_current->path).pop_right()
+				*m_base_path != PathName(m_current->path()).pop_right()
 			);
 		}
 
@@ -222,7 +222,7 @@ namespace mchlib {
 			assert(std::equal(m_list.begin(), m_list.end(), SetListing(ListType(m_list), true).sorted_list().begin()));
 		}
 		if (not m_list.empty()) {
-			m_base_path.reset(new PathName(m_list.front().path));
+			m_base_path.reset(new PathName(m_list.front().path()));
 		}
 	}
 
@@ -289,17 +289,17 @@ namespace mchlib {
 	}
 
 	SetListingView<false> SetListing::make_view() {
-		const auto offs = (m_list.empty() ? 0 : PathName(m_list.front().path).atom_count());
+		const auto offs = (m_list.empty() ? 0 : PathName(m_list.front().path()).atom_count());
 		return SetListingView<false>(m_list.begin(), m_list.end(), offs, m_base_path);
 	}
 
 	SetListingView<true> SetListing::make_view() const {
-		const auto offs = (m_list.empty() ? 0 : PathName(m_list.front().path).atom_count());
+		const auto offs = (m_list.empty() ? 0 : PathName(m_list.front().path()).atom_count());
 		return SetListingView<true>(m_list.begin(), m_list.end(), offs, m_base_path);
 	}
 
 	SetListingView<true> SetListing::make_cview() const {
-		const auto offs = (m_list.empty() ? 0 : PathName(m_list.front().path).atom_count());
+		const auto offs = (m_list.empty() ? 0 : PathName(m_list.front().path()).atom_count());
 		return SetListingView<true>(m_list.begin(), m_list.end(), offs, m_base_path);
 	}
 
@@ -311,7 +311,7 @@ namespace mchlib {
 		m_level_offset(parIter.m_level_offset)
 	{
 		if (m_begin != m_end) {
-			m_base_path.reset(new PathName(m_begin->path));
+			m_base_path.reset(new PathName(m_begin->path()));
 		}
 	}
 
@@ -323,7 +323,7 @@ namespace mchlib {
 		m_level_offset(parLevelOffset)
 	{
 		if (m_begin != m_end) {
-			m_base_path.reset(new PathName(m_begin->path));
+			m_base_path.reset(new PathName(m_begin->path()));
 		}
 	}
 

src/scan/dbbackend.cpp

@@ -60,7 +60,7 @@ namespace din {
 			if (parItem.abs_path.size() != 1 or parItem.abs_path != "/") {
 				parItem.abs_path = std::string("/") + parItem.abs_path;
 			}
-			parItem.path = boost::string_ref(parItem.abs_path).substr(1);
+			parItem.path_offset = 1;
 		}
 
 		{
@@ -125,9 +125,9 @@ namespace din {
 				"($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13);";
 
 			const auto& itm = parData[z];
-			assert(itm.path.data());
+			assert(itm.path().data());
 			conn.query(query,
-				(itm.path.empty() ? empty_path_string : itm.path),
+				(itm.path().empty() ? empty_path_string : itm.path()),
 				tiger_to_string(itm.hash),
 				itm.level,
 				new_group_id,