diablo: fix various of crashes in HeadlessMode

Patch fixes various crashes and accesses to the audio or SDL
subsystems that were not properly initialized in HeadlessMode:

 * Don't create an SDL window
 * Fully disable audio/sndfx during headless mode
 * Init SDL with SDL_INIT_EVENTS, otherwise an error:
       "The event system has been shut down"

Signed-off-by: Roman Penyaev <[email protected]>

Author: rouming

Source/diablo.cpp

@@ -1180,8 +1180,17 @@ void ApplicationInit()
 	if (*GetOptions().Graphics.showFPS)
 		EnableFrameCount();
 
-	init_create_window();
-	was_window_init = true;
+	if (!HeadlessMode) {
+		init_create_window();
+		was_window_init = true;
+	} else {
+#ifdef USE_SDL1
+		// Unfortunately no way to init only events queue for SDL1.2
+		SDL_Init(SDL_INIT_VIDEO);
+#else
+		SDL_Init(SDL_INIT_EVENTS);
+#endif
+	}
 
 	InitializeScreenReader();
 	LanguageInitialize();
@@ -1237,9 +1246,10 @@ void DiabloInit()
 
 	DiabloInitScreen();
 
-	snd_init();
-
-	ui_sound_init();
+	if (!HeadlessMode) {
+		snd_init();
+		ui_sound_init();
+	}
 
 	// Item graphics are loaded early, they already get touched during hero selection.
 	InitItemGFX();

Source/effects.cpp

@@ -312,6 +312,10 @@ void effects_play_sound(SfxID id)
 
 int GetSFXLength(SfxID nSFX)
 {
+	if (!gbSndInited || !gbSoundOn) {
+		return 0;
+	}
+
 	TSFX &sfx = sgSFX[static_cast<int16_t>(nSFX)];
 	if (sfx.pSnd == nullptr)
 		sfx.pSnd = sound_file_load(sfx.pszName.c_str(),

Source/engine/sound.cpp

@@ -152,6 +152,8 @@ int CapVolume(int volume)
 
 void OptionAudioChanged()
 {
+	if (HeadlessMode)
+		return;
 	effects_cleanup_sfx();
 	music_stop();
 	snd_deinit();
@@ -289,6 +291,9 @@ void music_start(_music_id nTrack)
 {
 	const char *trackPath;
 
+	if (HeadlessMode)
+		return;
+
 	assert(nTrack < NUM_MUSIC);
 	music_stop();
 	if (!gbMusicOn)

Source/hwcursor.cpp

@@ -16,6 +16,7 @@
 #include "engine/clx_sprite.hpp"
 #include "engine/render/clx_render.hpp"
 #include "engine/surface.hpp"
+#include "headless_mode.hpp"
 #include "utils/display.h"
 #include "utils/sdl_bilinear_scale.hpp"
 #include "utils/sdl_wrap.h"
@@ -164,6 +165,8 @@ void SetHardwareCursor(CursorInfo cursorInfo)
 #if SDL_VERSION_ATLEAST(2, 0, 0)
 	CurrentCursorInfo = cursorInfo;
 	CurrentCursorInfo.setNeedsReinitialization(false);
+	if (HeadlessMode)
+		return;
 	switch (cursorInfo.type()) {
 	case CursorType::Game:
 #if LOG_HWCURSOR

Source/menu.cpp

@@ -151,7 +151,7 @@ void mainmenu_loop()
 
 	do {
 		_mainmenu_selections menu = MAINMENU_NONE;
-		if (demo::IsRunning())
+		if (demo::IsRunning() || HeadlessMode)
 			menu = MAINMENU_SINGLE_PLAYER;
 		else if (!UiMainMenuDialog(gszProductName, &menu, 30))
 			app_fatal(_("Unable to display mainmenu"));

Source/minitext.cpp

@@ -17,6 +17,7 @@
 #include "engine/render/clx_render.hpp"
 #include "engine/render/primitive_render.hpp"
 #include "engine/render/text_render.hpp"
+#include "headless_mode.hpp"
 #include "playerdat.hpp"
 #include "textdat.h"
 #include "utils/language.h"
@@ -162,7 +163,7 @@ void InitQTextMsg(_speech_id m)
 	default:
 		break;
 	}
-	if (Speeches[m].scrlltxt) {
+	if (!HeadlessMode && Speeches[m].scrlltxt) {
 		QuestLogIsOpen = false;
 		LoadText(_(Speeches[m].txtstr));
 		qtextflag = true;