vfs: default constructor for Dirent and Stat

Fixes #1743

repos/os/include/vfs/directory_service.h

@@ -86,12 +86,12 @@ struct Vfs::Directory_service
 
 	struct Stat
 	{
-		file_size     size;
+		file_size     size   = 0;
-		unsigned      mode;
+		unsigned      mode   = 0;
-		unsigned      uid;
+		unsigned      uid    = 0;
-		unsigned      gid;
+		unsigned      gid    = 0;
-		unsigned long inode;
+		unsigned long inode  = 0;
-		unsigned long device;
+		unsigned long device = 0;
 	};
 
 	enum Stat_result { STAT_ERR_NO_ENTRY = NUM_GENERAL_ERRORS,
@@ -120,9 +120,9 @@ struct Vfs::Directory_service
 
 	struct Dirent
 	{
-		unsigned long fileno;
+		unsigned long fileno                    = 0;
-		Dirent_type   type;
+		Dirent_type   type                      = DIRENT_TYPE_END;
-		char          name[DIRENT_MAX_NAME_LEN];
+		char          name[DIRENT_MAX_NAME_LEN] = { 0 };
 	};
 
 	virtual Dirent_result dirent(char const *path, file_offset index, Dirent &) = 0;

repos/os/include/vfs/fs_file_system.h

@@ -255,7 +255,7 @@ class Vfs::Fs_file_system : public File_system
 			catch (::File_system::Lookup_failed)   { return STAT_ERR_NO_ENTRY; }
 			catch (::File_system::Out_of_metadata) { return STAT_ERR_NO_PERM;  }
 
-			memset(&out, 0, sizeof(out));
+			out = Stat();
 
 			out.size = status.size;
 			out.mode = STAT_MODE_FILE | 0777;

repos/os/include/vfs/single_file_system.h

@@ -70,7 +70,7 @@ class Vfs::Single_file_system : public File_system
 
 		Stat_result stat(char const *path, Stat &out) override
 		{
-			out = { 0, 0, 0, 0, 0, 0 };
+			out = Stat();
 			out.device = (Genode::addr_t)this;
 
 			if (_root(path)) {

repos/os/include/vfs/symlink_file_system.h

@@ -75,7 +75,7 @@ class Vfs::Symlink_file_system : public File_system
 
 		Stat_result stat(char const *path, Stat &out) override
 		{
-			out = { 0, 0, 0, 0, 0, 0 };
+			out = Stat();
 			out.device = (Genode::addr_t)this;
 
 			if (_root(path)) {

repos/os/include/vfs/tar_file_system.h

@@ -425,6 +425,8 @@ class Vfs::Tar_file_system : public File_system
 			if (verbose)
 				PDBG("path = %s", path);
 
+			out = Stat();
+
 			Node const *node = dereference(path);
 			if (!node)
 				return STAT_ERR_NO_ENTRY;
@@ -433,7 +435,6 @@ class Vfs::Tar_file_system : public File_system
 				if (verbose)
 					PDBG("found a virtual directoty node");
 
-				memset(&out, 0, sizeof(out));
 				out.mode = STAT_MODE_DIRECTORY;
 				return STAT_OK;
 			}
@@ -452,7 +453,6 @@ class Vfs::Tar_file_system : public File_system
 					PDBG("unhandled record type %d", record->type());
 			}
 
-			memset(&out, 0, sizeof(out));
 			out.mode  = mode;
 			out.size  = record->size();
 			out.uid   = record->uid();

repos/os/src/server/vfs/main.cc

@@ -452,10 +452,8 @@ class Vfs_server::Session_component :
 
 			Node &node = _lookup(node_handle);
 
-			if (_vfs.stat(node.path(), vfs_stat) != Directory_service::STAT_OK) {
+			if (_vfs.stat(node.path(), vfs_stat) != Directory_service::STAT_OK)
-				memset(&fs_stat, 0x00, sizeof(fs_stat));
 				return fs_stat;
-			}
 
 			fs_stat.inode = vfs_stat.inode;
 

repos/os/src/server/vfs/node.h

@@ -262,7 +262,6 @@ struct Vfs_server::Directory : Node
 		size_t remains = len;
 
 		while (remains >= blocksize) {
-			memset(&vfs_dirent, 0x00, sizeof(vfs_dirent));
 			if (vfs.dirent(path(), index++, vfs_dirent)
 				!= Vfs::Directory_service::DIRENT_OK)
 				return len - remains;

repos/ports/include/noux_session/sysio.h

@@ -82,7 +82,30 @@ namespace Noux {
 			STAT_MODE_BLOCKDEV  = 0060000,
 		};
 
-		typedef Vfs::Directory_service::Stat Stat;
+		/*
+		 * Must be POD (in contrast to the VFS type) because it's used in a union
+		 */
+		struct Stat
+		{
+			Vfs::file_size size;
+			unsigned       mode;
+			unsigned       uid;
+			unsigned       gid;
+			unsigned long  inode;
+			unsigned long  device;
+
+			Stat & operator= (Vfs::Directory_service::Stat const &stat)
+			{
+				size   = stat.size;
+				mode   = stat.mode;
+				uid    = stat.uid;
+				gid    = stat.gid;
+				inode  = stat.inode;
+				device = stat.device;
+
+				return *this;
+			}
+		};
 
 		/**
 		 * Argument structure used for ioctl syscall
@@ -107,7 +130,25 @@ namespace Noux {
 		enum { DIRENT_MAX_NAME_LEN = Vfs::Directory_service::DIRENT_MAX_NAME_LEN };
 
 		typedef Vfs::Directory_service::Dirent_type Dirent_type;
-		typedef Vfs::Directory_service::Dirent      Dirent;
+
+		/*
+		 * Must be POD (in contrast to the VFS type) because it's used in a union
+		 */
+		struct Dirent
+		{
+			unsigned long fileno;
+			Dirent_type   type;
+			char          name[DIRENT_MAX_NAME_LEN];
+
+			Dirent & operator= (Vfs::Directory_service::Dirent const &dirent)
+			{
+				fileno = dirent.fileno;
+				type   = dirent.type;
+				memcpy(name, dirent.name, DIRENT_MAX_NAME_LEN);
+
+				return *this;
+			}
+		};
 
 		enum Fcntl_cmd {
 			FCNTL_CMD_GET_FILE_STATUS_FLAGS,

repos/ports/src/noux/vfs_io_channel.h

@@ -85,8 +85,9 @@ namespace Noux {
 			 * 'sysio.stat_in' is not used in '_fh->ds().stat()',
 			 * so no 'sysio' member translation is needed here
 			 */
-			sysio->error.stat =  _fh->ds().stat(_leaf_path.base(),
+			Vfs::Directory_service::Stat stat;
-			                                    sysio->fstat_out.st);
+			sysio->error.stat =  _fh->ds().stat(_leaf_path.base(), stat);
+			sysio->fstat_out.st = stat;
 
 			return (sysio->error.stat == Vfs::Directory_service::STAT_OK);
 
@@ -149,9 +150,10 @@ namespace Noux {
 			 * Align index range to zero when calling the directory service.
 			 */
 
-			if (!_fh->ds().dirent(_path.base(), index - 2,
+			Vfs::Directory_service::Dirent dirent;
-			                      sysio->dirent_out.entry))
+			if (!_fh->ds().dirent(_path.base(), index - 2, dirent))
 				return false;
+			sysio->dirent_out.entry = dirent;
 
 			_fh->advance_seek(sizeof(Sysio::Dirent));
 			return true;