SCUMM: Simplify index file handling for Steam versions.

This also makes sure that all extra needed detection data for the Steam
releases is located inside detection.cpp.

4 files changed, 50 insertions, 43 deletions

diff --git a/engines/scumm/detection.cpp b/engines/scumm/detection.cpp
index e77047d1b7..87c1aa1505 100644
--- a/engines/scumm/detection.cpp
+++ b/engines/scumm/detection.cpp
@@ -211,14 +211,29 @@ Common::String ScummEngine_v70he::generateFilename(const int room) const {
 	return result;
 }
 
-static const char *getSteamExeNameFromPattern(Common::String pattern, Common::Platform platform) {
+// The following table includes all the index files, which are embedded in the
+// main game executables in Steam versions.
+static const SteamIndexFile steamIndexFiles[] = {
+	{ GID_INDY3, Common::kPlatformWindows,   "%02d.LFL",      "00.LFL",       "Indiana Jones and the Last Crusade.exe",     162056,  6295 },
+	{ GID_INDY3, Common::kPlatformMacintosh, "%02d.LFL",      "00.LFL",       "The Last Crusade",                           150368,  6295 },
+	{ GID_INDY4, Common::kPlatformWindows,   "atlantis.%03d", "ATLANTIS.000",  "Indiana Jones and the Fate of Atlantis.exe", 224336, 12035 },
+	{ GID_INDY4, Common::kPlatformMacintosh, "atlantis.%03d", "ATLANTIS.000",  "The Fate of Atlantis",                       260224, 12035 },
+	{ GID_LOOM,  Common::kPlatformWindows,   "%03d.LFL",      "000.LFL",       "Loom.exe",                                   187248,  8307 },
+	{ GID_LOOM,  Common::kPlatformMacintosh, "%03d.LFL",      "000.LFL",       "Loom",                                       170464,  8307 },
+#ifdef ENABLE_SCUMM_7_8
+	{ GID_DIG,   Common::kPlatformWindows,   "dig.la%d",      "DIG.LA0",       "The Dig.exe",                                340632, 16304 },
+	{ GID_DIG,   Common::kPlatformMacintosh, "dig.la%d",      "DIG.LA0",       "The Dig",                                    339744, 16304 },
+#endif
+	{ 0,         Common::kPlatformUnknown,   "",              "",              "",                                                0,     0 }
+};
+
+const SteamIndexFile *lookUpSteamIndexFile(Common::String pattern, Common::Platform platform) {
 	for (const SteamIndexFile *indexFile = steamIndexFiles; indexFile->len; ++indexFile) {
 		if (platform == indexFile->platform && pattern.equalsIgnoreCase(indexFile->pattern))
-			return indexFile->executableName;
+			return indexFile;
 	}
 
-	error("Unable to find Steam executable from detection pattern");
-	return "";
+	return nullptr;
 }
 
 static Common::String generateFilenameForDetection(const char *pattern, FilenameGenMethod genMethod, Common::Platform platform) {
@@ -231,9 +246,14 @@ static Common::String generateFilenameForDetection(const char *pattern, Filename
 		break;
 	
 	case kGenDiskNumSteam:
-	case kGenRoomNumSteam:
-		result = getSteamExeNameFromPattern(pattern, platform);
-		break;
+	case kGenRoomNumSteam: {
+		const SteamIndexFile *indexFile = lookUpSteamIndexFile(pattern, platform);
+		if (!indexFile) {
+			error("Unable to find Steam executable from detection pattern");
+		} else {
+			result = indexFile->executableName;
+		}
+		} break;
 
 	case kGenHEPC:
 	case kGenHEIOS:
diff --git a/engines/scumm/file.cpp b/engines/scumm/file.cpp
index 8f6fdbe0cf..475ffa3238 100644
--- a/engines/scumm/file.cpp
+++ b/engines/scumm/file.cpp
@@ -29,22 +29,6 @@
 
 namespace Scumm {
 
-// The following table includes all the index files, which are embedded in the
-// main game executables in Steam versions.
-const SteamIndexFile steamIndexFiles[] = {
-	{ GID_INDY3, Common::kPlatformWindows,   "%02d.LFL",      "00.LFL",       "Indiana Jones and the Last Crusade.exe",     162056,  6295 },
-	{ GID_INDY3, Common::kPlatformMacintosh, "%02d.LFL",      "00.LFL",       "The Last Crusade",                           150368,  6295 },
-	{ GID_INDY4, Common::kPlatformWindows,   "atlantis.%03d", "ATLANTIS.000",  "Indiana Jones and the Fate of Atlantis.exe", 224336, 12035 },
-	{ GID_INDY4, Common::kPlatformMacintosh, "atlantis.%03d", "ATLANTIS.000",  "The Fate of Atlantis",                       260224, 12035 },
-	{ GID_LOOM,  Common::kPlatformWindows,   "%03d.LFL",      "000.LFL",       "Loom.exe",                                   187248,  8307 },
-	{ GID_LOOM,  Common::kPlatformMacintosh, "%03d.LFL",      "000.LFL",       "Loom",                                       170464,  8307 },
-#ifdef ENABLE_SCUMM_7_8
-	{ GID_DIG,   Common::kPlatformWindows,   "dig.la%d",      "DIG.LA0",       "The Dig.exe",                                340632, 16304 },
-	{ GID_DIG,   Common::kPlatformMacintosh, "dig.la%d",      "DIG.LA0",       "The Dig",                                    339744, 16304 },
-#endif
-	{ 0,         Common::kPlatformUnknown,   "",              "",              "",                                                0,     0 }
-};
-
 #pragma mark -
 #pragma mark --- ScummFile ---
 #pragma mark -
@@ -205,13 +189,12 @@ uint32 ScummFile::read(void *dataPtr, uint32 dataSize) {
 #pragma mark -
 
 bool ScummSteamFile::open(const Common::String &filename) {
-	for (const SteamIndexFile *indexFile = steamIndexFiles; indexFile->len; ++indexFile) {
-		if (indexFile->id == _steamGame.id && indexFile->platform == _steamGame.platform && filename.equalsIgnoreCase(indexFile->indexFileName))
-			return openWithSubRange(indexFile->executableName, indexFile->start, indexFile->len);
+	if (filename.equalsIgnoreCase(_indexFile.indexFileName)) {
+		return openWithSubRange(_indexFile.executableName, _indexFile.start, _indexFile.len);
+	} else {
+		// Regular non-bundled file
+		return ScummFile::open(filename);
 	}
-
-	// Regular non-bundled file
-	return ScummFile::open(filename);
 }
 
 bool ScummSteamFile::openWithSubRange(const Common::String &filename, int32 subFileStart, int32 subFileLen) {
diff --git a/engines/scumm/file.h b/engines/scumm/file.h
index f3eaac5d32..e7c1eb6d71 100644
--- a/engines/scumm/file.h
+++ b/engines/scumm/file.h
@@ -76,18 +76,6 @@ public:
 	uint32 read(void *dataPtr, uint32 dataSize);
 };
 
-class ScummSteamFile : public ScummFile {
-private:
-	GameSettings _steamGame;
-
-	bool openWithSubRange(const Common::String &filename, int32 subFileStart, int32 subFileLen);
-
-public:
-	ScummSteamFile(GameSettings game) : ScummFile(), _steamGame(game) {}
-
-	bool open(const Common::String &filename);
-};
-
 class ScummDiskImage : public BaseScummFile {
 private:
 	Common::SeekableReadStream *_stream;
@@ -142,7 +130,18 @@ struct SteamIndexFile {
 	int32 len;
 };
 
-extern const SteamIndexFile steamIndexFiles[];
+const SteamIndexFile *lookUpSteamIndexFile(Common::String pattern, Common::Platform platform);
+
+class ScummSteamFile : public ScummFile {
+private:
+	const SteamIndexFile &_indexFile;
+
+	bool openWithSubRange(const Common::String &filename, int32 subFileStart, int32 subFileLen);
+public:
+	ScummSteamFile(const SteamIndexFile &indexFile) : ScummFile(), _indexFile(indexFile) {}
+
+	bool open(const Common::String &filename);
+};
 
 } // End of namespace Scumm
 
diff --git a/engines/scumm/scumm.cpp b/engines/scumm/scumm.cpp
index 8c0325934d..73776bad5a 100644
--- a/engines/scumm/scumm.cpp
+++ b/engines/scumm/scumm.cpp
@@ -1161,7 +1161,12 @@ Common::Error ScummEngine::init() {
 	} else {
 		if (_filenamePattern.genMethod == kGenDiskNumSteam || _filenamePattern.genMethod == kGenRoomNumSteam) {
 			// Steam game versions have the index file embedded in the main executable
-			_fileHandle = new ScummSteamFile(_game);
+			const SteamIndexFile *indexFile = lookUpSteamIndexFile(_filenamePattern.pattern, _game.platform);
+			if (!indexFile || indexFile->id != _game.id) {
+				error("Couldn't find index file description for Steam version");
+			} else {
+				_fileHandle = new ScummSteamFile(*indexFile);
+			}
 		} else {
 			// Regular access, no container file involved
 			_fileHandle = new ScummFile();