Avoid using unions for LongDirEntry.

GCC still assumes that the dirent has no data past the end for some
scenarios here and still mis-optimizes things. Therefore, drop the
usages of unions altogether, and instead use a casted character array.

Additionally, use B_FILE_NAME_LENGTH for the array, not B_PATH_NAME_LENGTH,
and make sure to add 1 for the NULL terminator.

headers/private/storage/storage_support.h

@@ -25,9 +25,9 @@ namespace BPrivate {
 namespace Storage {
 
 // For convenience:
-union LongDirEntry {
+struct LongDirEntry {
-	struct dirent dirent;
+	char _[sizeof(struct dirent) + B_FILE_NAME_LENGTH + 1];
-	char _[sizeof(struct dirent) + B_PATH_NAME_LENGTH];
+	struct dirent* dirent() { return (struct dirent*)_; }
 };
 
 //! Returns whether the supplied path is absolute.
@@ -73,9 +73,9 @@ void to_lower(const char *str, std::string &result);
 
 /*! \brief Copies \c str into \c result, converting any uppercase alphabetics
 	to lowercase.
-	
+
 	\a str and \a result may point to the same string. \a result is
-	assumed to be as long as or longer than \a str. 
+	assumed to be as long as or longer than \a str.
 */
 void to_lower(const char *str, char *result);
 
@@ -87,7 +87,7 @@ void to_lower(char *str);
 	\a result must be large enough to accomodate the addition of
 	escape sequences to \a str. \a str and \a result may *NOT* point to
 	the same string.
-	
+
 	Note that this function was designed for use with the registrar's
 	RecentEntries class, and may not create escapes exactly like you're
 	hoping.	Please double check the code for the function to see if this

src/build/libbe/storage/Directory.cpp

@@ -333,7 +333,7 @@ BDirectory::GetNextRef(entry_ref* ref)
 		return B_FILE_ERROR;
 
 	BPrivate::Storage::LongDirEntry longEntry;
-	struct dirent* entry = &longEntry.dirent;
+	struct dirent* entry = longEntry.dirent();
 	bool next = true;
 	while (next) {
 		if (GetNextDirents(entry, sizeof(longEntry), 1) != 1)
@@ -377,7 +377,7 @@ BDirectory::CountEntries()
 		return error;
 	int32 count = 0;
 	BPrivate::Storage::LongDirEntry longEntry;
-	struct dirent* entry = &longEntry.dirent;
+	struct dirent* entry = longEntry.dirent();
 	while (error == B_OK) {
 		if (GetNextDirents(entry, sizeof(longEntry), 1) != 1)
 			break;

src/build/libbe/storage/MergedDirectory.cpp

@@ -110,7 +110,7 @@ status_t
 BMergedDirectory::GetNextRef(entry_ref* ref)
 {
 	BPrivate::Storage::LongDirEntry longEntry;
-	struct dirent* dirEntry = &longEntry.dirent;
+	struct dirent* dirEntry = longEntry.dirent();
 	int32 result = GetNextDirents(dirEntry, sizeof(longEntry), 1);
 	if (result < 0)
 		return result;

src/build/libbe/storage/Node.cpp

@@ -310,7 +310,7 @@ BNode::GetNextAttrName(char* buffer)
 		return B_FILE_ERROR;
 
 	BPrivate::Storage::LongDirEntry longEntry;
-	struct dirent* entry = &longEntry.dirent;
+	struct dirent* entry = longEntry.dirent();
 	ssize_t result = _kern_read_dir(fAttrFd, entry, sizeof(longEntry), 1);
 	if (result < 0)
 		return result;

src/build/libroot/fs_attr_untyped.cpp

@@ -129,10 +129,10 @@ class AttributeDirectory;
 typedef map<DIR*, AttributeDirectory*> AttrDirMap;
 static AttrDirMap sAttributeDirectories;
 
-// LongDirent
+// LongDirEntry
-union LongDirent {
+struct LongDirEntry {
-	struct dirent dirent;
+	char _[sizeof(struct dirent) + B_FILE_NAME_LENGTH + 1];
-	char _[sizeof(struct dirent) + B_FILE_NAME_LENGTH];
+	struct dirent* dirent() { return (struct dirent*)_; }
 };
 
 // AttributeHeader
@@ -260,11 +260,11 @@ public:
 			}
 
 			// prepare the dirent
-			strcpy(fDirent.dirent.d_name, name);
+			strcpy(fDirent.dirent()->d_name, name);
-			fDirent.dirent.d_ino = 0;
+			fDirent.dirent()->d_ino = 0;
 // TODO: We need the node ID!
 
-			*_entry = &fDirent.dirent;
+			*_entry = fDirent.dirent();
 			return B_OK;
 		}
 
@@ -309,7 +309,7 @@ private:
 	int			fFileFD;
 	string		fPath;
 	DIR*		fFakeDir;
-	LongDirent	fDirent;
+	LongDirEntry fDirent;
 	char*		fListing;
 	int			fListingLength;
 	int			fListingIndex;

src/kits/storage/Directory.cpp

@@ -353,7 +353,7 @@ BDirectory::GetNextRef(entry_ref* ref)
 		return B_FILE_ERROR;
 
 	BPrivate::Storage::LongDirEntry longEntry;
-	struct dirent* entry = &longEntry.dirent;
+	struct dirent* entry = longEntry.dirent();
 	bool next = true;
 	while (next) {
 		if (GetNextDirents(entry, sizeof(longEntry), 1) != 1)
@@ -397,7 +397,7 @@ BDirectory::CountEntries()
 		return error;
 	int32 count = 0;
 	BPrivate::Storage::LongDirEntry longEntry;
-	struct dirent* entry = &longEntry.dirent;
+	struct dirent* entry = longEntry.dirent();
 	while (error == B_OK) {
 		if (GetNextDirents(entry, sizeof(longEntry), 1) != 1)
 			break;

src/kits/storage/MergedDirectory.cpp

@@ -112,7 +112,7 @@ status_t
 BMergedDirectory::GetNextRef(entry_ref* ref)
 {
 	BPrivate::Storage::LongDirEntry longEntry;
-	struct dirent* entry = &longEntry.dirent;
+	struct dirent* entry = longEntry.dirent();
 	int32 result = GetNextDirents(entry, sizeof(longEntry), 1);
 	if (result < 0)
 		return result;

src/kits/storage/Node.cpp

@@ -320,7 +320,7 @@ BNode::GetNextAttrName(char* buffer)
 		return B_FILE_ERROR;
 
 	BPrivate::Storage::LongDirEntry longEntry;
-	struct dirent* entry = &longEntry.dirent;
+	struct dirent* entry = longEntry.dirent();
 	ssize_t result = _kern_read_dir(fAttrFd, entry, sizeof(longEntry), 1);
 	if (result < 0)
 		return result;

src/kits/storage/Query.cpp

@@ -349,7 +349,7 @@ BQuery::GetNextRef(entry_ref* ref)
 		error = B_FILE_ERROR;
 	if (error == B_OK) {
 		BPrivate::Storage::LongDirEntry longEntry;
-		struct dirent* entry = &longEntry.dirent;
+		struct dirent* entry = longEntry.dirent();
 		bool next = true;
 		while (error == B_OK && next) {
 			if (GetNextDirents(entry, sizeof(longEntry), 1) != 1) {

src/kits/tracker/VirtualDirectoryEntryList.cpp

@@ -83,7 +83,7 @@ status_t
 VirtualDirectoryEntryList::GetNextRef(entry_ref* ref)
 {
 	BPrivate::Storage::LongDirEntry longEntry;
-	struct dirent* entry = &longEntry.dirent;
+	struct dirent* entry = longEntry.dirent();
 	int32 result = GetNextDirents(entry, sizeof(longEntry), 1);
 	if (result < 0)
 		return result;

src/kits/tracker/VirtualDirectoryPoseView.cpp

@@ -209,7 +209,7 @@ VirtualDirectoryPoseView::_EntryCreated(const BMessage* message)
 			return true;
 
 		BPrivate::Storage::LongDirEntry longEntry;
-		struct dirent* entry = &longEntry.dirent;
+		struct dirent* entry = longEntry.dirent();
 		while (directory.GetNextDirents(entry, sizeof(longEntry), 1) == 1) {
 			if (strcmp(entry->d_name, ".") != 0
 				&& strcmp(entry->d_name, "..") != 0) {

src/system/boot/loader/vfs.cpp

@@ -42,10 +42,9 @@ using namespace boot;
 struct __DIR {
 	Directory*	directory;
 	void*		cookie;
-	union {
+
-		dirent		entry;
+	char		_direntBuffer[sizeof(dirent) + B_FILE_NAME_LENGTH + 1];
-		char		nameBuffer[sizeof(dirent) + B_FILE_NAME_LENGTH - 1];
+	dirent*		entry() { return (dirent*)_direntBuffer; }
-	};
 };
 
 
@@ -1260,33 +1259,33 @@ readdir(DIR* dir)
 
 	for (;;) {
 		status_t error = dir->directory->GetNextEntry(dir->cookie,
-			dir->entry.d_name, B_FILE_NAME_LENGTH);
+			dir->entry()->d_name, B_FILE_NAME_LENGTH);
 		if (error != B_OK) {
 			errno = error;
 			return NULL;
 		}
 
-		dir->entry.d_pdev = 0;
+		dir->entry()->d_pdev = 0;
 			// not supported
-		dir->entry.d_pino = dir->directory->Inode();
+		dir->entry()->d_pino = dir->directory->Inode();
-		dir->entry.d_dev = dir->entry.d_pdev;
+		dir->entry()->d_dev = dir->entry()->d_pdev;
 			// not supported
 
-		if (strcmp(dir->entry.d_name, ".") == 0
+		if (strcmp(dir->entry()->d_name, ".") == 0
-				|| strcmp(dir->entry.d_name, "..") == 0) {
+				|| strcmp(dir->entry()->d_name, "..") == 0) {
 			// Note: That's obviously not correct for "..", but we can't
 			// retrieve that information.
-			dir->entry.d_ino = dir->entry.d_pino;
+			dir->entry()->d_ino = dir->entry()->d_pino;
 		} else {
-			Node* node = dir->directory->Lookup(dir->entry.d_name, false);
+			Node* node = dir->directory->Lookup(dir->entry()->d_name, false);
 			if (node == NULL)
 				continue;
 
-			dir->entry.d_ino = node->Inode();
+			dir->entry()->d_ino = node->Inode();
 			node->Release();
 		}
 
-		return &dir->entry;
+		return dir->entry();
 	}
 }