renderDX11: fix crash when font tex fails to load

issue #1217

extern/imgui_patched/backends/imgui_impl_dx11.cpp

@@ -339,8 +339,8 @@ static void ImGui_ImplDX11_CreateFontsTexture()
         subResource.SysMemPitch = desc.Width * 4;
         subResource.SysMemSlicePitch = 0;
         bd->pd3dDevice->CreateTexture2D(&desc, &subResource, &pTexture);
-        IM_ASSERT(pTexture != nullptr);
 
+        if (pTexture != nullptr) {
           // Create texture view
           D3D11_SHADER_RESOURCE_VIEW_DESC srvDesc;
           ZeroMemory(&srvDesc, sizeof(srvDesc));
@@ -350,6 +350,11 @@ static void ImGui_ImplDX11_CreateFontsTexture()
           srvDesc.Texture2D.MostDetailedMip = 0;
           bd->pd3dDevice->CreateShaderResourceView(pTexture, &srvDesc, &bd->pFontTextureView);
           pTexture->Release();
+        } else {
+          bd->pFontTextureView=NULL;
+          bd->pFontSampler=NULL;
+          return;
+        }
     }
 
     // Store our identifier
@@ -609,13 +614,15 @@ void ImGui_ImplDX11_Shutdown()
     IM_DELETE(bd);
 }
 
-void ImGui_ImplDX11_NewFrame()
+bool ImGui_ImplDX11_NewFrame()
 {
     ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
     IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplDX11_Init()?");
 
     if (!bd->pFontSampler)
         ImGui_ImplDX11_CreateDeviceObjects();
+    
+    return bd->pFontSampler!=NULL;
 }
 
 //--------------------------------------------------------------------------------------------------------

extern/imgui_patched/backends/imgui_impl_dx11.h

@@ -19,7 +19,7 @@ struct ID3D11DeviceContext;
 
 IMGUI_IMPL_API bool     ImGui_ImplDX11_Init(ID3D11Device* device, ID3D11DeviceContext* device_context);
 IMGUI_IMPL_API void     ImGui_ImplDX11_Shutdown();
-IMGUI_IMPL_API void     ImGui_ImplDX11_NewFrame();
+IMGUI_IMPL_API bool     ImGui_ImplDX11_NewFrame();
 IMGUI_IMPL_API void     ImGui_ImplDX11_RenderDrawData(ImDrawData* draw_data);
 
 // Use if you want to reset your rendering device without losing Dear ImGui state.

papers/multiplayer.md

@@ -0,0 +1,402 @@
+# multiplayer protocol
+
+the Furnace protocol is described here.
+
+# information
+
+all numbers are little-endian.
+
+the following fields may be found in "size":
+- `f` indicates a floating point number.
+- `STR` is a UTF-8 zero-terminated string.
+- `CFG` is the same as STR, but contains a config.
+- `???` is an array of variable size.
+- `S??` is an array of `STR`s.
+- `1??` is an array of bytes.
+- `2??` is an array of shorts.
+- `4??` is an array of ints.
+
+two player IDs are reserved:
+- 0: system
+- 1: host (console)
+
+two usernames are reserved:
+- SYSTEM
+- HOST
+
+some characters are not allowed in usernames: 0x00-0x1f, `@`, 0x7f-0x9f, 0xd800-0xdfff, 0xfeff, 0xfffe and 0xffff.
+
+# header
+
+size | description
+-----|------------------------------------
+  3  | "fur" header
+  1  | packet type
+  4  | sequence number
+
+the sequence number always starts at 0.
+
+# client to server packets (init)
+
+## 0x00: keep-alive
+
+this packet keeps a connection alive.
+the server shall respond with a packet of type 0x00 (keep-alive).
+if the client does not receive any packets during 30 seconds, it will disconnect from the server.
+likewise, if the server does not receive any packets during 30 seconds, it will disconnect the client.
+
+## 0x01: start connection
+
+size | description
+-----|------------------------------------
+  1  | reason
+     | - 0: information
+     | - 1: join
+  3  | padding
+  4  | client version
+ STR | host name (may be blank)
+
+after sending, you will receive a packet of type 0x01 (information), 0x02 (disconnect) or 0x03 (authenticate).
+
+## 0x02: disconnect
+
+size | description
+-----|------------------------------------
+ STR | reason
+
+## 0x03: auth response
+
+size | description
+-----|------------------------------------
+  1  | type
+     | - 0: open
+     | - 1: password
+     | - 2: token
+ --- | **open response**
+ STR | username
+ --- | **password response**
+  1  | password type
+     | - 0: plain text
+     | - 1: SHA-512
+ STR | account name
+ ??? | password
+ --- | **token response**
+ STR | token
+
+# server to client packets (init)
+
+## 0x00: keep-alive
+
+this packet keeps a connection alive. it is a response to a client's keep-alive packet.
+
+## 0x01: information
+
+size | description
+-----|------------------------------------
+  4  | server version
+  2  | online players
+     | - if it is 65535, this information is concealed.
+  2  | maximum players
+     | - 0 means unlimited.
+ STR | server version (string)
+ STR | server name
+ STR | server description
+ STR | project name
+
+the client may send a 0x00 (keep-alive) packet after receiving this one within 5 seconds.
+connection is then closed.
+
+## 0x02: disconnect
+
+size | description
+-----|------------------------------------
+ STR | reason
+
+after being sent, the connection is closed.
+
+## 0x03: authenticate
+
+size | description
+-----|------------------------------------
+  1  | authentication type
+     | - 0: open
+     | - 1: password
+     | - 2: token
+
+## 0x04: authentication success
+
+size | description
+-----|------------------------------------
+  4  | player ID
+ STR | username
+ CFG | properties
+
+# client to server packets (session)
+
+## 0x10: request project
+
+the client may only send this once every minute.
+
+## 0x11: participate
+
+size | description
+-----|------------------------------------
+  1  | status
+     | - 0: spectate
+     | - 1: join
+
+## 0x12: send chat message
+
+size | description
+-----|------------------------------------
+ STR | message
+
+## 0x13: send command
+
+size | description
+-----|------------------------------------
+ STR | command
+  2  | number of arguments
+ S?? | arguments
+
+## 0x14: get player list
+
+no other information required.
+
+## 0x15: project submission request
+
+no other information required
+
+## 0x16: project submission information
+
+size | description
+-----|------------------------------------
+  4  | project size
+ 32  | SHA-256 sum of project
+ STR | project name
+
+this is followed by several 0x17 (project data) packets representing a Furnace song. see [format.md](format.md) for more information.
+
+## 0x17: project submission data
+
+size | description
+-----|------------------------------------
+  4  | offset
+  4  | length
+ ??? | data...
+
+the client will send a packet with project size as offset and 0 as length to indicate end of data.
+the server subsequently loads the project.
+
+# server to client packets (session)
+
+## 0x10: project information
+
+size | description
+-----|------------------------------------
+  4  | project size
+ 32  | SHA-256 sum of project
+ STR | project name
+
+this is followed by several 0x13 (project data) packets representing a Furnace song. see [format.md](format.md) for more information.
+
+## 0x11: project data
+
+size | description
+-----|------------------------------------
+  4  | offset
+  4  | length
+ ??? | data...
+
+the server will send a packet with project size as offset and 0 as length to indicate end of data.
+the client subsequently loads the project.
+
+## 0x12: participate status
+
+size | description
+-----|------------------------------------
+  1  | status
+     | - 0: denied
+     | - 1: allowed
+
+## 0x13: message
+
+size | description
+-----|------------------------------------
+  4  | player ID
+  8  | time (seconds)
+  4  | time (nanoseconds)
+  4  | message ID
+  1  | type
+     | - 0: chat, public
+     | - 1: chat, private
+     | - 2: notification, info
+     | - 3: notification, warning
+     | - 4: notification, urgent
+ STR | message
+
+## 0x14: system message
+
+size | description
+-----|------------------------------------
+ STR | message
+
+## 0x15: chat message edited
+
+size | description
+-----|------------------------------------
+  4  | message ID
+ STR | message
+     | - an empty message means deleted.
+
+## 0x16: player list
+
+size | description
+-----|------------------------------------
+  2  | number of players
+ --- | **player entry** (×players)
+  4  | ID
+  2  | latency (ms)
+  1  | participating?
+     | - 0: no
+     | - 1: yes
+  1  | status
+     | - 0: normal
+     | - 1: away
+     | - 2: busy
+ STR | name
+ STR | IP address
+     | - if empty, then server is not disclosing IP addresses.
+
+this is sent after receiving 0x14 (get player list).
+
+## 0x17: project submission request status
+
+size | description
+-----|------------------------------------
+  1  | status
+     | - 0: denied
+     | - 1: allowed
+
+this is sent after a project submission request is accepted.
+if the status is 1, the client shall submit a project.
+
+## 0x18: project submission complete
+
+size | description
+-----|------------------------------------
+  1  | status
+     | - 0: error
+     | - 1: success
+ STR | additional information
+
+## 0x19: player joined
+
+size | description
+-----|------------------------------------
+  4  | ID
+ STR | name
+
+## 0x1a: player left
+
+size | description
+-----|------------------------------------
+  4  | ID
+
+# client to server packets (project)
+
+## 0x20: request orders
+
+## 0x21: request instrument
+
+## 0x22: request wavetable
+
+## 0x23: request sample
+
+## 0x24: request patterns
+
+## 0x25: request sub-song
+
+## 0x26: request song info
+
+## 0x27: request asset list
+
+## 0x28: request patchbay
+
+## 0x29: request grooves
+
+## 0x30: alter orders
+
+size | description
+-----|------------------------------------
+  4  | transaction ID
+
+## 0x31: alter instrument
+
+## 0x32: alter wavetable
+
+## 0x33: alter sample
+
+## 0x34: alter pattern
+
+## 0x35: alter sub-song
+
+## 0x36: alter song info
+
+## 0x37: alter asset list
+
+## 0x38: alter patchbay
+
+## 0x39: alter grooves
+
+## 0x3a: alter chips
+
+## 0x3b: alter chip settings
+
+# server to client packets (project)
+
+## 0x20: orders
+
+## 0x21: instrument
+
+## 0x22: wavetable
+
+## 0x23: sample
+
+## 0x24: pattern
+
+## 0x25: sub-song
+
+## 0x26: song info
+
+## 0x27: asset list
+
+## 0x28: patchbay
+
+## 0x29: grooves
+
+## 0x30: transaction response
+
+size | description
+-----|------------------------------------
+  1  | status
+     | - 0: error
+     | - 1: success
+     | - 2: success but request again
+ STR | additional information
+
+# client to server packets (interact)
+
+## 0x40: engine command
+
+## 0x41: playback
+
+# server to client packets (interact)
+
+## 0x40: engine command
+
+## 0x41: playback
+
+# client to server packets (extension)
+
+# server to client packets (extension)

src/engine/platform/sound/ymfm/ymfm_opn.cpp

@@ -141,6 +141,7 @@ template<bool IsOpnA>
 bool opn_registers_base<IsOpnA>::write(uint16_t index, uint8_t data, uint32_t &channel, uint32_t &opmask)
 {
 	assert(index < REGISTERS);
+  if (index >= REGISTERS) return false;
 
 	// writes in the 0xa0-af/0x1a0-af region are handled as latched pairs
 	// borrow unused registers 0xb8-bf/0x1b8-bf as temporary holding locations

src/gui/render/renderDX11.cpp

@@ -290,8 +290,7 @@ void FurnaceGUIRenderDX11::clear(ImVec4 color) {
 }
 
 bool FurnaceGUIRenderDX11::newFrame() {
-  ImGui_ImplDX11_NewFrame();
+  return ImGui_ImplDX11_NewFrame();
-  return true;
 }
 
 void FurnaceGUIRenderDX11::createFontsTexture() {