Try next archive type if file not found, not just on open error

src/emu/fileio.cpp

@@ -626,41 +626,39 @@ bool emu_file::part_of_mediapath(std::string path)
 
 osd_file::error emu_file::attempt_zipped()
 {
-	std::string filename;
+	typedef util::archive_file::error (*open_func)(const std::string &filename, util::archive_file::ptr &result);
+	char const *const suffixes[] = { ".zip", ".7z" };
+	open_func const open_funcs[ARRAY_LENGTH(suffixes)] = { &util::archive_file::open_zip, &util::archive_file::open_7z };
 
+	// loop over archive types
+	std::string const savepath(m_fullpath);
+	std::string filename;
+	for (unsigned i = 0; i < ARRAY_LENGTH(suffixes); i++, m_fullpath = savepath, filename.clear())
+	{
 		// loop over directory parts up to the start of filename
 		while (1)
 		{
 			// find the final path separator
 			auto const dirsep = m_fullpath.find_last_of(PATH_SEPARATOR[0]);
 			if (dirsep == std::string::npos)
-			return osd_file::error::NOT_FOUND;
+				break;
 
 			if (restrict_to_mediapath() && !part_of_mediapath(m_fullpath))
-			return osd_file::error::NOT_FOUND;
+				break;
 
 			// insert the part from the right of the separator into the head of the filename
-		if (filename.length() > 0)
+			if (!filename.empty()) filename.insert(0, 1, '/');
-			filename.insert(0, "/");
+			filename.insert(0, m_fullpath.substr(dirsep + 1, std::string::npos));
-		filename.insert(0, m_fullpath.substr(dirsep + 1, -1));
 
-		// remove this part of the filename and append a .zip extension
+			// remove this part of the filename and append an archive extension
-		m_fullpath = m_fullpath.substr(0, dirsep).append(".zip");
+			m_fullpath.resize(dirsep);
+			m_fullpath.append(suffixes[i]);
 
-		// attempt to open the ZIP file
+			// attempt to open the archive file
 			util::archive_file::ptr zip;
-		util::archive_file::error ziperr = util::archive_file::open_zip(m_fullpath, zip);
+			util::archive_file::error ziperr = open_funcs[i](m_fullpath, zip);
 
-		if (ziperr != util::archive_file::error::NONE)
+			// chop the archive suffix back off the filename before continuing
-		{
-			// remove this part of the filename and append a .7z extension
-			m_fullpath = m_fullpath.substr(0, dirsep).append(".7z");
-
-			// attempt to open the 7zip file
-			ziperr = util::archive_file::open_7z(m_fullpath, zip);
-		}
-
-		// chop the .zip/.7z back off the filename before continuing
 			m_fullpath = m_fullpath.substr(0, dirsep);
 
 			// if we failed to open this file, continue scanning
@@ -669,15 +667,15 @@ osd_file::error emu_file::attempt_zipped()
 
 			int header = -1;
 
-		// see if we can find a file with the right name and (if available) crc
+			// see if we can find a file with the right name and (if available) CRC
 			if (m_openflags & OPEN_FLAG_HAS_CRC) header = zip->search(m_crc, filename, false);
 			if (header < 0 && (m_openflags & OPEN_FLAG_HAS_CRC)) header = zip->search(m_crc, filename, true);
 
-		// if that failed, look for a file with the right crc, but the wrong filename
+			// if that failed, look for a file with the right CRC, but the wrong filename
 			if (header < 0 && (m_openflags & OPEN_FLAG_HAS_CRC)) header = zip->search(m_crc);
 
-		// if that failed, look for a file with the right name; reporting a bad checksum
+			// if that failed, look for a file with the right name;
-		// is more helpful and less confusing than reporting "rom not found"
+			// reporting a bad checksum is more helpful and less confusing than reporting "ROM not found"
 			if (header < 0) header = zip->search(filename, false);
 			if (header < 0) header = zip->search(filename, true);
 
@@ -693,9 +691,11 @@ osd_file::error emu_file::attempt_zipped()
 				return (m_openflags & OPEN_FLAG_NO_PRELOAD) ? osd_file::error::NONE : load_zipped_file();
 			}
 
-		// close up the ZIP file and try the next level
+			// close up the archive file and try the next level
 			zip.reset();
 		}
+	}
+	return osd_file::error::NOT_FOUND;
 }