GLK: Centralizing more of the savegame code in GlkEngine

8 files changed, 281 insertions, 251 deletions

diff --git a/engines/glk/frotz/frotz.cpp b/engines/glk/frotz/frotz.cpp
index a6371b6ef3..344aa92b12 100644
--- a/engines/glk/frotz/frotz.cpp
+++ b/engines/glk/frotz/frotz.cpp
@@ -84,13 +84,174 @@ void Frotz::initialize() {
 	z_restart();
 }
 
-Common::Error Frotz::loadGameState(int slot) {
-	// TODO
+Common::Error Frotz::saveGameData(strid_t file) {
+#ifdef TODO
+	long pc;
+	zword addr;
+	zword nsp, nfp;
+	int skip;
+	int i;
+
+	/* Open game file */
+
+	if ((gfp = frotzopenprompt(FILE_SAVE)) == nullptr)
+		goto finished;
+
+	if (_save_quetzal) {
+		success = save_quetzal(gfp, story_fp, blorb_ofs);
+	}
+	else {
+		/* Write game file */
+
+		fputc((int)hi(h_release), gfp);
+		fputc((int)lo(h_release), gfp);
+		fputc((int)hi(h_checksum), gfp);
+		fputc((int)lo(h_checksum), gfp);
+
+		GET_PC(pc)
+
+			fputc((int)(pc >> 16) & 0xff, gfp);
+		fputc((int)(pc >> 8) & 0xff, gfp);
+		fputc((int)(pc)& 0xff, gfp);
+
+		nsp = (int)(_sp - _stack);
+		nfp = (int)(_fp - _stack);
+
+		fputc((int)hi(nsp), gfp);
+		fputc((int)lo(nsp), gfp);
+		fputc((int)hi(nfp), gfp);
+		fputc((int)lo(nfp), gfp);
+
+		for (i = nsp; i < STACK_SIZE; i++) {
+			fputc((int)hi(_stack[i]), gfp);
+			fputc((int)lo(_stack[i]), gfp);
+		}
+
+		fseek(story_fp, blorb_ofs, SEEK_SET);
+
+		for (addr = 0, skip = 0; addr < h_dynamic_size; addr++)
+			if (zmp[addr] != fgetc(story_fp) || skip == 255 || addr + 1 == h_dynamic_size) {
+				fputc(skip, gfp);
+				fputc(zmp[addr], gfp);
+				skip = 0;
+			}
+			else skip++;
+	}
+
+	/* Close game file and check for errors */
+
+	if (fclose(gfp) == EOF || ferror(story_fp)) {
+		print_string("Error writing save file\n");
+		goto finished;
+	}
+
+	/* Success */
+
+	success = 1;
+#endif
 	return Common::kNoError;
 }
 
-Common::Error Frotz::saveGameState(int slot, const Common::String &desc) {
-	// TODO
+Common::Error Frotz::loadGameData(strid_t file) {
+#ifdef TODO
+	long pc;
+	zword release;
+	zword addr;
+	int i;
+
+	/* Open game file */
+
+	if ((gfp = frotzopenprompt(FILE_RESTORE)) == nullptr)
+		goto finished;
+
+	if (_save_quetzal) {
+		success = restore_quetzal (gfp, story_fp, blorb_ofs);
+
+	} else {
+		/* Load game file */
+
+		release = (unsigned) fgetc (gfp) << 8;
+		release |= fgetc (gfp);
+
+		() fgetc (gfp);
+		() fgetc (gfp);
+
+		/* Check the release number */
+
+		if (release == h_release) {
+
+			pc = (long) fgetc (gfp) << 16;
+			pc |= (unsigned) fgetc (gfp) << 8;
+			pc |= fgetc (gfp);
+
+			SET_PC (pc);
+
+			_sp = _stack + (fgetc (gfp) << 8);
+			_sp += fgetc (gfp);
+			_fp = _stack + (fgetc (gfp) << 8);
+			_fp += fgetc (gfp);
+
+			for (i = (int) (_sp - _stack); i < STACK_SIZE; i++) {
+				_stack[i] = (unsigned) fgetc (gfp) << 8;
+				_stack[i] |= fgetc (gfp);
+			}
+
+			fseek (story_fp, blorb_ofs, SEEK_SET);
+
+			for (addr = 0; addr < h_dynamic_size; addr++) {
+				int skip = fgetc (gfp);
+				for (i = 0; i < skip; i++)
+					zmp[addr++] = fgetc (story_fp);
+				zmp[addr] = fgetc (gfp);
+				() fgetc (story_fp);
+			}
+
+			/* Check for errors */
+
+			if (ferror (gfp) || ferror (story_fp) || addr != h_dynamic_size)
+				success = -1;
+			else
+
+				/* Success */
+
+				success = 2;
+
+		} else print_string ("Invalid save file\n");
+	}
+
+	if ((short) success >= 0) {
+
+		/* Close game file */
+
+		fclose (gfp);
+
+		if ((short) success > 0) {
+			zbyte old_screen_rows;
+			zbyte old_screen_cols;
+
+			/* In V3, reset the upper window. */
+			if (h_version == V3)
+				split_window (0);
+
+			LOW_BYTE (H_SCREEN_ROWS, old_screen_rows);
+			LOW_BYTE (H_SCREEN_COLS, old_screen_cols);
+
+			/* Reload cached header fields. */
+			restart_header ();
+
+			/*
+				* Since QUETZAL files may be saved on many different machines,
+				* the screen sizes may vary a lot. Erasing the status window
+				* seems to cover up most of the resulting badness.
+				*/
+			if (h_version > V3 && h_version != V6
+					&& (h_screen_rows != old_screen_rows
+						|| h_screen_cols != old_screen_cols))
+				erase_window (1);
+		}
+	} else
+		os_fatal ("Error reading save file");
+#endif
 	return Common::kNoError;
 }
 
diff --git a/engines/glk/frotz/frotz.h b/engines/glk/frotz/frotz.h
index e45abc07a8..00aeb599fb 100644
--- a/engines/glk/frotz/frotz.h
+++ b/engines/glk/frotz/frotz.h
@@ -54,14 +54,14 @@ public:
 	virtual void runGame(Common::SeekableReadStream *gameFile) override;
 
 	/**
-	 * Load a savegame
+	 * Load a savegame from the passed stream
 	 */
-	virtual Common::Error loadGameState(int slot) override;
+	virtual Common::Error loadGameData(strid_t file) override;
 
 	/**
-	 * Save the game
+	 * Save the game to the passed stream
 	 */
-	virtual Common::Error saveGameState(int slot, const Common::String &desc) override;
+	virtual Common::Error saveGameData(strid_t file) override;
 };
 
 extern Frotz *g_vm;
diff --git a/engines/glk/frotz/processor_streams.cpp b/engines/glk/frotz/processor_streams.cpp
index 091165ed7c..cbef38aaa6 100644
--- a/engines/glk/frotz/processor_streams.cpp
+++ b/engines/glk/frotz/processor_streams.cpp
@@ -545,227 +545,54 @@ void Processor::z_restart() {
 }
 
 void Processor::z_save() {
-#ifdef TODO
 	bool success = false;
 
 	if (zargc != 0) {
 		// Open auxilary file
 		frefid_t ref = glk_fileref_create_by_prompt(fileusage_Data | fileusage_BinaryMode,
 			filemode_Write, 0);
-		if (ref == nullptr)
-			goto finished;
+		if (ref != nullptr) {
+			// Write data
+			strid_t f = glk_stream_open_file(ref, filemode_Write);
 
-		// Write data
-		strid_t f = glk_stream_open_file(ref, filemode_Write);
+			glk_put_buffer_stream(f, (const char *)zmp + zargs[0], zargs[1]);
 
-		glk_put_buffer_stream(f, (const char *)zmp + zargs[0], zargs[1]);
-
-		glk_stream_close(f);
-
-	} else {
-		long pc;
-		zword addr;
-		zword nsp, nfp;
-		int skip;
-		int i;
-
-		/* Open game file */
-
-		if ((gfp = frotzopenprompt (FILE_SAVE)) == nullptr)
-			goto finished;
-
-		if (_save_quetzal) {
-			success = save_quetzal (gfp, story_fp, blorb_ofs);
-		} else {
-			/* Write game file */
-
-			fputc ((int) hi (h_release), gfp);
-			fputc ((int) lo (h_release), gfp);
-			fputc ((int) hi (h_checksum), gfp);
-			fputc ((int) lo (h_checksum), gfp);
-
-			GET_PC (pc)
-
-				fputc ((int) (pc >> 16) & 0xff, gfp);
-			fputc ((int) (pc >> 8) & 0xff, gfp);
-			fputc ((int) (pc) & 0xff, gfp);
-
-			nsp = (int) (_sp - _stack);
-			nfp = (int) (_fp - _stack);
-
-			fputc ((int) hi (nsp), gfp);
-			fputc ((int) lo (nsp), gfp);
-			fputc ((int) hi (nfp), gfp);
-			fputc ((int) lo (nfp), gfp);
-
-			for (i = nsp; i < STACK_SIZE; i++) {
-				fputc ((int) hi (_stack[i]), gfp);
-				fputc ((int) lo (_stack[i]), gfp);
-			}
-
-			fseek (story_fp, blorb_ofs, SEEK_SET);
-
-			for (addr = 0, skip = 0; addr < h_dynamic_size; addr++)
-				if (zmp[addr] != fgetc (story_fp) || skip == 255 || addr + 1 == h_dynamic_size) {
-					fputc (skip, gfp);
-					fputc (zmp[addr], gfp);
-					skip = 0;
-				} else skip++;
+			glk_stream_close(f);
+			success = true;
 		}
-
-		/* Close game file and check for errors */
-
-		if (fclose (gfp) == EOF || ferror (story_fp)) {
-			print_string ("Error writing save file\n");
-			goto finished;
-		}
-
-		/* Success */
-
-		success = 1;
-
+	} else {
+		success = saveGame().getCode() == Common::kNoError;
 	}
 
-finished:
-
 	if (h_version <= V3)
 		branch (success);
 	else
 		store (success);
-#endif
 }
 
 void Processor::z_restore() {
-#ifdef TODO
-	FILE *gfp;
-
-	zword success = 0;
+	bool success = false;
 
 	if (zargc != 0) {
+		frefid_t ref = glk_fileref_create_by_prompt(fileusage_Data | fileusage_BinaryMode,
+			filemode_Read, 0);
+		if (ref != nullptr) {
+			// Write data
+			strid_t f = glk_stream_open_file(ref, filemode_Read);
 
-		/* Get the file name */
-
-		/* Open auxilary file */
-
-		if ((gfp = frotzopenprompt(FILE_LOAD_AUX)) == nullptr)
-			goto finished;
-
-		/* Load auxilary file */
-
-		success = fread (zmp + zargs[0], 1, zargs[1], gfp);
-
-		/* Close auxilary file */
-
-		fclose (gfp);
-
-	} else {
-
-		long pc;
-		zword release;
-		zword addr;
-		int i;
-
-		/* Open game file */
-
-		if ((gfp = frotzopenprompt(FILE_RESTORE)) == nullptr)
-			goto finished;
-
-		if (_save_quetzal) {
-			success = restore_quetzal (gfp, story_fp, blorb_ofs);
-
-		} else {
-			/* Load game file */
-
-			release = (unsigned) fgetc (gfp) << 8;
-			release |= fgetc (gfp);
-
-			() fgetc (gfp);
-			() fgetc (gfp);
-
-			/* Check the release number */
-
-			if (release == h_release) {
-
-				pc = (long) fgetc (gfp) << 16;
-				pc |= (unsigned) fgetc (gfp) << 8;
-				pc |= fgetc (gfp);
-
-				SET_PC (pc);
-
-				_sp = _stack + (fgetc (gfp) << 8);
-				_sp += fgetc (gfp);
-				_fp = _stack + (fgetc (gfp) << 8);
-				_fp += fgetc (gfp);
-
-				for (i = (int) (_sp - _stack); i < STACK_SIZE; i++) {
-					_stack[i] = (unsigned) fgetc (gfp) << 8;
-					_stack[i] |= fgetc (gfp);
-				}
-
-				fseek (story_fp, blorb_ofs, SEEK_SET);
-
-				for (addr = 0; addr < h_dynamic_size; addr++) {
-					int skip = fgetc (gfp);
-					for (i = 0; i < skip; i++)
-						zmp[addr++] = fgetc (story_fp);
-					zmp[addr] = fgetc (gfp);
-					() fgetc (story_fp);
-				}
-
-				/* Check for errors */
-
-				if (ferror (gfp) || ferror (story_fp) || addr != h_dynamic_size)
-					success = -1;
-				else
-
-					/* Success */
-
-					success = 2;
+			glk_get_buffer_stream(f, (char *)zmp + zargs[0], zargs[1]);
 
-			} else print_string ("Invalid save file\n");
+			glk_stream_close(f);
+			success = true;
 		}
-
-		if ((short) success >= 0) {
-
-			/* Close game file */
-
-			fclose (gfp);
-
-			if ((short) success > 0) {
-				zbyte old_screen_rows;
-				zbyte old_screen_cols;
-
-				/* In V3, reset the upper window. */
-				if (h_version == V3)
-					split_window (0);
-
-				LOW_BYTE (H_SCREEN_ROWS, old_screen_rows);
-				LOW_BYTE (H_SCREEN_COLS, old_screen_cols);
-
-				/* Reload cached header fields. */
-				restart_header ();
-
-				/*
-				 * Since QUETZAL files may be saved on many different machines,
-				 * the screen sizes may vary a lot. Erasing the status window
-				 * seems to cover up most of the resulting badness.
-				 */
-				if (h_version > V3 && h_version != V6
-						&& (h_screen_rows != old_screen_rows
-							|| h_screen_cols != old_screen_cols))
-					erase_window (1);
-			}
-		} else
-			os_fatal ("Error reading save file");
+	} else {
+		success = loadGame().getCode() == Common::kNoError;
 	}
 
-finished:
-
 	if (h_version <= V3)
 		branch (success);
 	else
 		store (success);
-#endif
 }
 
 void Processor::z_verify() {
diff --git a/engines/glk/glk.cpp b/engines/glk/glk.cpp
index 987fbc894a..a3cd167ae7 100644
--- a/engines/glk/glk.cpp
+++ b/engines/glk/glk.cpp
@@ -117,4 +117,56 @@ void GlkEngine::GUIError(const char *msg, ...) {
 	GUIErrorMessage(buffer);
 }
 
+Common::Error GlkEngine::loadGame() {
+	frefid_t ref = _streams->createByPrompt(fileusage_BinaryMode | fileusage_SavedGame,
+		filemode_Read, 0);
+	if (ref == nullptr)
+		return Common::kReadingFailed;
+
+	int slotNumber = ref->_slotNumber;
+	_streams->deleteRef(ref);
+
+	return loadGameState(slotNumber);
+}
+
+Common::Error GlkEngine::saveGame() {
+	frefid_t ref = _streams->createByPrompt(fileusage_BinaryMode | fileusage_SavedGame,
+		filemode_Write, 0);
+	if (ref == nullptr)
+		return Common::kWritingFailed;
+
+	int slot = ref->_slotNumber;
+	Common::String desc = ref->_description;
+	_streams->deleteRef(ref);
+
+	return saveGameState(slot, desc);
+}
+
+Common::Error GlkEngine::loadGameState(int slot) {
+	FileReference ref(slot, "", fileusage_SavedGame | fileusage_TextMode);
+
+	strid_t file = _streams->openFileStream(&ref, filemode_Read);
+	if (file == nullptr)
+		return Common::kReadingFailed;
+
+	Common::Error result = saveGameData(file);
+
+	file->close();
+	return result;
+}
+
+Common::Error GlkEngine::saveGameState(int slot, const Common::String &desc) {
+	Common::String msg;
+	FileReference ref(slot, desc, fileusage_BinaryMode | fileusage_SavedGame);
+
+	strid_t file = _streams->openFileStream(&ref, filemode_Write);
+	if (file == nullptr)
+		return Common::kWritingFailed;
+
+	Common::Error result = loadGameData(file);
+
+	file->close();
+	return result;
+}
+
 } // End of namespace Glk
diff --git a/engines/glk/glk.h b/engines/glk/glk.h
index 8dce78f085..f925fd0cc3 100644
--- a/engines/glk/glk.h
+++ b/engines/glk/glk.h
@@ -30,6 +30,7 @@
 #include "engines/advancedDetector.h"
 #include "engines/engine.h"
 #include "glk/glk_types.h"
+#include "glk/streams.h"
 
 namespace Glk {
 
@@ -181,6 +182,11 @@ public:
 	}
 
 	/**
+	 * Display a message in a GUI dialog
+	 */
+	void GUIError(const char *msg, ...);
+
+	/**
 	 * Return the filename for a given save slot
 	 */
 	Common::String getSaveName(uint slot) const {
@@ -188,9 +194,34 @@ public:
 	}
 
 	/**
-	 * Display a message in a GUI dialog
+	 * Prompt the user for a savegame to load, and then load it
 	 */
-	void GUIError(const char *msg, ...);
+	Common::Error loadGame();
+
+	/**
+	 * Prompt the user to save their game, and then save it
+	 */
+	Common::Error saveGame();
+
+	/**
+	 * Load a savegame from a given slot
+	 */
+	virtual Common::Error loadGameState(int slot) override;
+
+	/**
+	 * Save the game to a given slot
+	 */
+	virtual Common::Error saveGameState(int slot, const Common::String &desc) override;
+
+	/**
+	 * Load a savegame from the passed file
+	 */
+	virtual Common::Error loadGameData(strid_t file) = 0;
+
+	/**
+	 * Save the game to the passed file
+	 */
+	virtual Common::Error saveGameData(strid_t file) = 0;
 };
 
 extern GlkEngine *g_vm;
diff --git a/engines/glk/scott/scott.cpp b/engines/glk/scott/scott.cpp
index fed31f014e..cbc5886130 100644
--- a/engines/glk/scott/scott.cpp
+++ b/engines/glk/scott/scott.cpp
@@ -309,7 +309,7 @@ void Scott::loadDatabase(Common::SeekableReadStream *f, bool loud) {
 	if (loud)
 		debug("Reading %d actions.", na);
 
-	for (uint idx = 0; idx < na + 1; ++idx) {
+	for (int idx = 0; idx < na + 1; ++idx) {
 		Action &a = _actions[idx];
 		readInts(f, 8,
 			&a._vocab, &a._condition[0], &a._condition[1], &a._condition[2],
@@ -503,26 +503,8 @@ void Scott::lineInput(char *buf, size_t n) {
 	buf[ev.val1] = 0;
 }
 
-void Scott::saveGame(void) {
-	frefid_t ref = glk_fileref_create_by_prompt(fileusage_TextMode | fileusage_SavedGame,
-	               filemode_Write, 0);
-	if (ref == nullptr)
-		return;
-
-	int slot = ref->_slotNumber;
-	Common::String desc = ref->_description;
-	glk_fileref_destroy(ref);
-
-	saveGameState(slot, desc);
-}
-
-Common::Error Scott::saveGameState(int slot, const Common::String &desc) {
+Common::Error Scott::saveGameData(strid_t file) {
 	Common::String msg;
-	FileReference ref(slot, desc, fileusage_TextMode | fileusage_SavedGame);
-
-	strid_t file = glk_stream_open_file(&ref, filemode_Write, 0);
-	if (file == nullptr)
-		return Common::kWritingFailed;
 
 	for (int ct = 0; ct < 16; ct++) {
 		msg = Common::String::format("%d %d\n", _counters[ct], _roomSaved[ct]);
@@ -539,37 +521,16 @@ Common::Error Scott::saveGameState(int slot, const Common::String &desc) {
 		glk_put_string_stream(file, msg.c_str());
 	}
 
-	glk_stream_close(file, nullptr);
 	output("Saved.\n");
-
 	return Common::kNoError;
 }
 
-void Scott::loadGame(void) {
-	frefid_t ref = glk_fileref_create_by_prompt(fileusage_TextMode | fileusage_SavedGame,
-	               filemode_Read, 0);
-	if (ref == nullptr)
-		return;
-
-	int slotNumber = ref->_slotNumber;
-	glk_fileref_destroy(ref);
-
-	loadGameState(slotNumber);
-}
-
-Common::Error Scott::loadGameState(int slot) {
-	strid_t file;
+Common::Error Scott::loadGameData(strid_t file) {
 	char buf[128];
 	int ct = 0;
 	short lo;
 	short darkFlag;
 
-	FileReference ref(slot, "", fileusage_SavedGame | fileusage_TextMode);
-
-	file = glk_stream_open_file(&ref, filemode_Read, 0);
-	if (file == nullptr)
-		return Common::kReadingFailed;
-
 	for (ct = 0; ct < 16; ct++) {
 		glk_get_line_stream(file, buf, sizeof buf);
 		sscanf(buf, "%d %d", &_counters[ct], &_roomSaved[ct]);
diff --git a/engines/glk/scott/scott.h b/engines/glk/scott/scott.h
index 4741892687..a22f88bf94 100644
--- a/engines/glk/scott/scott.h
+++ b/engines/glk/scott/scott.h
@@ -153,8 +153,6 @@ private:
 	void look(void);
 	int whichWord(const char *word, const Common::StringArray &list);
 	void lineInput(char *buf, size_t n);
-	void saveGame(void);
-	void loadGame(void);
 	int getInput(int *vb, int *no);
 	int performLine(int ct);
 	int performActions(int vb, int no);
@@ -174,14 +172,14 @@ public:
 	virtual void runGame(Common::SeekableReadStream *gameFile) override;
 
 	/**
-	 * Load a savegame
+	 * Load a savegame from the passed stream
 	 */
-	virtual Common::Error loadGameState(int slot) override;
+	virtual Common::Error loadGameData(strid_t file) override;
 
 	/**
-	 * Save the game
+	 * Save the game to the passed stream
 	 */
-	virtual Common::Error saveGameState(int slot, const Common::String &desc) override;
+	virtual Common::Error saveGameData(strid_t file) override;
 };
 
 } // End of namespace Scott
diff --git a/engines/glk/streams.h b/engines/glk/streams.h
index 22a0a59602..3150ce9c38 100644
--- a/engines/glk/streams.h
+++ b/engines/glk/streams.h
@@ -563,7 +563,7 @@ public:
 	/**
 	 * Open a file stream
 	 */
-	FileStream *openFileStream(frefid_t fref, glui32 fmode, glui32 rock, bool unicode);
+	FileStream *openFileStream(frefid_t fref, glui32 fmode, glui32 rock = 0, bool unicode = false);
 
 	/**
 	 * Open a window stream