🎉 Stream videos on Linux and FreeBSD

Previously, we always loaded entire videos in memory before playing them.

`libsmacker` does not provide a streaming API but it does provide a
`FILE *` file pointer API.

We now take advantage of the `FILE *` API by streaming the videos on
platforms that support `fopencookie`.

This means faster startup and less memory usage on these platforms.

CMakeLists.txt

@@ -388,6 +388,7 @@ set(devilutionx_SRCS
   Source/dvlnet/loopback.cpp
   Source/dvlnet/packet.cpp
   Source/storm/storm.cpp
+  Source/storm/storm_file_wrapper.cpp
   Source/storm/storm_net.cpp
   Source/storm/storm_sdl_rw.cpp
   Source/storm/storm_svid.cpp

Source/movie.cpp

@@ -37,28 +37,28 @@ void play_movie(const char *pszMovie, bool user_can_close)
 	effects_play_sound("Sfx\\Misc\\blank.wav");
 #endif
 
-	SVidPlayBegin(pszMovie, loop_movie ? 0x100C0808 : 0x10280808, &video_stream);
-	tagMSG Msg;
-	while (video_stream != nullptr && movie_playing) {
-		while (movie_playing && FetchMessage(&Msg)) {
-			switch (Msg.message) {
-			case DVL_WM_KEYDOWN:
-			case DVL_WM_LBUTTONDOWN:
-			case DVL_WM_RBUTTONDOWN:
-				if (user_can_close || (Msg.message == DVL_WM_KEYDOWN && Msg.wParam == DVL_VK_ESCAPE))
-					movie_playing = false;
-				break;
-			case DVL_WM_QUIT:
-				SVidPlayEnd(video_stream);
-				diablo_quit(0);
-				break;
+	if (SVidPlayBegin(pszMovie, loop_movie ? 0x100C0808 : 0x10280808, &video_stream)) {
+		tagMSG Msg;
+		while (movie_playing) {
+			while (movie_playing && FetchMessage(&Msg)) {
+				switch (Msg.message) {
+				case DVL_WM_KEYDOWN:
+				case DVL_WM_LBUTTONDOWN:
+				case DVL_WM_RBUTTONDOWN:
+					if (user_can_close || (Msg.message == DVL_WM_KEYDOWN && Msg.wParam == DVL_VK_ESCAPE))
+						movie_playing = false;
+					break;
+				case DVL_WM_QUIT:
+					SVidPlayEnd(video_stream);
+					diablo_quit(0);
+					break;
+				}
 			}
+			if (!SVidPlayContinue())
+				break;
 		}
-		if (!SVidPlayContinue())
-			break;
-	}
-	if (video_stream != nullptr)
 		SVidPlayEnd(video_stream);
+	}
 
 #ifndef NOSOUND
 	sound_disable_music(false);

Source/storm/storm_file_wrapper.cpp

@@ -0,0 +1,74 @@
+#include "storm_file_wrapper.h"
+
+#ifdef DEVILUTIONX_STORM_FILE_WRAPPER_AVAILABLE
+
+#include "storm/storm.h"
+#include "utils/log.hpp"
+
+namespace devilution {
+extern "C" {
+
+#ifdef DEVILUTIONX_STORM_FILE_WRAPPER_IMPL_FOPENCOOKIE
+
+ssize_t SFileCookieRead(void *cookie, char *buf, size_t nbytes)
+{
+	DWORD numRead = 0;
+	if (!SFileReadFile(static_cast<HANDLE>(cookie), buf, nbytes, &numRead, nullptr)) {
+		const DWORD errCode = SErrGetLastError();
+		if (errCode != STORM_ERROR_HANDLE_EOF) {
+			Log("SFileRwRead error: {} ERROR CODE {}", (unsigned int)nbytes, (unsigned int)errCode);
+		}
+	}
+	return numRead;
+}
+
+int SFileCookieSeek(void *cookie, off64_t *pos, int whence)
+{
+	int swhence;
+	switch (whence) {
+	case SEEK_SET:
+		swhence = DVL_FILE_BEGIN;
+		break;
+	case SEEK_CUR:
+		swhence = DVL_FILE_CURRENT;
+		break;
+	case SEEK_END:
+		swhence = DVL_FILE_END;
+		break;
+	default:
+		return -1;
+	}
+	const std::uint64_t spos = SFileSetFilePointer(static_cast<HANDLE>(cookie), *pos, swhence);
+	if (spos == static_cast<std::uint64_t>(-1)) {
+		Log("SFileRwSeek error: {}", (unsigned int)SErrGetLastError());
+		return -1;
+	}
+	*pos = static_cast<off64_t>(spos);
+	return 0;
+}
+
+int SFileCookieClose(void *cookie)
+{
+	return SFileCloseFile(static_cast<HANDLE>(cookie)) ? 0 : -1;
+}
+
+} // extern "C"
+#endif
+
+FILE *FILE_FromStormHandle(HANDLE handle)
+{
+#ifdef DEVILUTIONX_STORM_FILE_WRAPPER_IMPL_FOPENCOOKIE
+	cookie_io_functions_t ioFns;
+	std::memset(&ioFns, 0, sizeof(ioFns));
+	ioFns.read = &SFileCookieRead;
+	ioFns.seek = &SFileCookieSeek;
+	ioFns.close = &SFileCookieClose;
+	return fopencookie(handle, "rb", ioFns);
+#else
+#error "unimplemented"
+#endif
+}
+
+} // namespace devilution
+
+#endif

Source/storm/storm_file_wrapper.h

@@ -0,0 +1,17 @@
+/** A pointer to a Storm file as a `FILE *`. Only available on some platforms. */
+#pragma once
+#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
+#include <cstdio>
+
+#include "miniwin/miniwin.h"
+
+#define DEVILUTIONX_STORM_FILE_WRAPPER_AVAILABLE
+#define DEVILUTIONX_STORM_FILE_WRAPPER_IMPL_FOPENCOOKIE
+
+namespace devilution {
+
+FILE *FILE_FromStormHandle(HANDLE handle);
+
+} // namespace devilution
+
+#endif

Source/storm/storm_svid.cpp

@@ -17,10 +17,11 @@
 #include "dx.h"
 #include "options.h"
 #include "palette.h"
+#include "storm/storm_file_wrapper.h"
 #include "storm/storm.h"
 #include "utils/display.h"
-#include "utils/sdl_compat.h"
 #include "utils/log.hpp"
+#include "utils/sdl_compat.h"
 
 namespace devilution {
 namespace {
@@ -39,7 +40,10 @@ smk SVidSMK;
 SDL_Color SVidPreviousPalette[256];
 SDL_Palette *SVidPalette;
 SDL_Surface *SVidSurface;
+
+#ifndef DEVILUTIONX_STORM_FILE_WRAPPER_AVAILABLE
 std::unique_ptr<uint8_t[]> SVidBuffer;
+#endif
 
 bool IsLandscapeFit(unsigned long srcW, unsigned long srcH, unsigned long dstW, unsigned long dstH)
 {
@@ -129,10 +133,10 @@ bool SVidLoadNextFrame()
 
 } // namespace
 
-void SVidPlayBegin(const char *filename, int flags, HANDLE *video)
+bool SVidPlayBegin(const char *filename, int flags, HANDLE *video)
 {
 	if (flags & 0x10000 || flags & 0x20000000) {
-		return;
+		return false;
 	}
 
 	SVidLoop = false;
@@ -146,14 +150,19 @@ void SVidPlayBegin(const char *filename, int flags, HANDLE *video)
 	//0x200800 // Clear FB
 
 	SFileOpenFile(filename, video);
-
+#ifdef DEVILUTIONX_STORM_FILE_WRAPPER_AVAILABLE
+	FILE *file = FILE_FromStormHandle(*video);
+	SVidSMK = smk_open_filepointer(file, SMK_MODE_DISK);
+#else
 	int bytestoread = SFileGetFileSize(*video, nullptr);
 	SVidBuffer = std::make_unique<uint8_t[]>(bytestoread);
 	SFileReadFile(*video, SVidBuffer.get(), bytestoread, nullptr, nullptr);
-
+	SFileCloseFile(*video);
+	*video = nullptr;
 	SVidSMK = smk_open_memory(SVidBuffer.get(), bytestoread);
+#endif
 	if (SVidSMK == nullptr) {
-		return;
+		return false;
 	}
 
 #ifndef NOSOUND
@@ -236,6 +245,7 @@ void SVidPlayBegin(const char *filename, int flags, HANDLE *video)
 
 	SVidFrameEnd = SDL_GetTicks() * 1000 + SVidFrameLength;
 	SDL_FillRect(GetOutputSurface(), nullptr, 0x000000);
+	return true;
 }
 
 bool SVidPlayContinue()
@@ -358,7 +368,9 @@ void SVidPlayEnd(HANDLE video)
 	if (SVidSMK != nullptr)
 		smk_close(SVidSMK);
 
+#ifndef DEVILUTIONX_STORM_FILE_WRAPPER_AVAILABLE
 	SVidBuffer = nullptr;
+#endif
 
 	SDL_FreePalette(SVidPalette);
 	SVidPalette = nullptr;
@@ -366,9 +378,6 @@ void SVidPlayEnd(HANDLE video)
 	SDL_FreeSurface(SVidSurface);
 	SVidSurface = nullptr;
 
-	SFileCloseFile(video);
-	video = nullptr;
-
 	memcpy(orig_palette, SVidPreviousPalette, sizeof(orig_palette));
 #ifndef USE_SDL1
 	if (renderer != nullptr) {

Source/storm/storm_svid.h

@@ -4,7 +4,7 @@
 
 namespace devilution {
 
-void SVidPlayBegin(const char *filename, int flags, HANDLE *video);
+bool SVidPlayBegin(const char *filename, int flags, HANDLE *video);
 bool SVidPlayContinue();
 void SVidPlayEnd(HANDLE video);