Threaded emscripten fixes (#17614)

* Actually read CLI args in emscripten

* Fix fetchfs manifest parsing, increase download chunk size

The chunk size should probably be made a parameter in the future.  The
larger chunk size trades longer hitches for fewer hitches.

* Add exec command driver and API functions for emscripten.

Under WASMFS, stdin/stdout can't be customized the way they can with
the JS FS implementation.  Also, this approach frees up stdin/stdout
and simplifies interaction with the command interface for web embedders.

* fixup upload paths, show use of new emscripten cmd interface

* Add JS library function names to EXPORTS as well as EXPORTED_FUNCTIONS for older emsdk versions

Makefile.emscripten

@@ -102,9 +102,9 @@ OBJDIR := obj-emscripten
 EXPORTED_FUNCTIONS = _main,_malloc,_free,_cmd_savefiles,_cmd_save_state,_cmd_load_state,_cmd_undo_save_state,_cmd_undo_load_state,_cmd_take_screenshot,\
 _cmd_toggle_menu,_cmd_reload_config,_cmd_toggle_grab_mouse,_cmd_toggle_game_focus,_cmd_reset,_cmd_toggle_pause,_cmd_pause,_cmd_unpause,\
 _cmd_set_volume,_cmd_set_shader,_cmd_cheat_set_code,_cmd_cheat_get_code,_cmd_cheat_toggle_index,_cmd_cheat_get_code_state,_cmd_cheat_realloc,\
-_cmd_cheat_get_size,_cmd_cheat_apply_cheats
+_cmd_cheat_get_size,_cmd_cheat_apply_cheats,EmscriptenSendCommand,EmscriptenReceiveCommandReply
 
-EXPORTS := callMain,FS,PATH,ERRNO_CODES,ENV,stringToNewUTF8,UTF8ToString,Browser,GL
+EXPORTS := callMain,FS,PATH,ERRNO_CODES,ENV,stringToNewUTF8,UTF8ToString,Browser,GL,EmscriptenSendCommand,EmscriptenReceiveCommandReply
 
 LIBS    := -s USE_ZLIB=1 -lbrowser.js
 

command.c

@@ -337,7 +337,7 @@ command_t* command_stdin_new(void)
    command_t *cmd;
    command_stdin_t *stdincmd;
 
-#ifndef _WIN32
+#if !(defined(_WIN32) || defined(EMSCRIPTEN))
 #ifdef HAVE_NETWORKING
    if (!socket_nonblock(STDIN_FILENO))
       return NULL;
@@ -363,6 +363,61 @@ command_t* command_stdin_new(void)
 }
 #endif
 
+#if defined(EMSCRIPTEN)
+void PlatformEmscriptenCommandReply(const char *, size_t);
+int PlatformEmscriptenCommandRead(char **, size_t);
+typedef struct
+{
+   char command_buf[CMD_BUF_SIZE];
+} command_emscripten_t;
+
+static void emscripten_command_reply(command_t *_cmd,
+   const char *s, size_t len)
+{
+   PlatformEmscriptenCommandReply(s, len);
+}
+
+static void emscripten_command_free(command_t *handle)
+{
+   free(handle->userptr);
+   free(handle);
+}
+
+static void command_emscripten_poll(command_t *handle)
+{
+   command_emscripten_t *emscriptencmd = (command_emscripten_t*)handle->userptr;
+   ptrdiff_t msg_len = PlatformEmscriptenCommandRead((char **)(&emscriptencmd->command_buf), CMD_BUF_SIZE);
+   if (msg_len == 0)
+      return;
+   command_parse_msg(handle, emscriptencmd->command_buf);
+}
+
+command_t* command_emscripten_new(void)
+{
+   command_t *cmd;
+   command_emscripten_t *emscriptencmd;
+
+   cmd           = (command_t*)calloc(1, sizeof(command_t));
+   emscriptencmd = (command_emscripten_t*)calloc(1, sizeof(command_emscripten_t));
+
+   if (!cmd)
+      return NULL;
+   if (!emscriptencmd)
+   {
+      free(cmd);
+      return NULL;
+   }
+   cmd->userptr = emscriptencmd;
+   cmd->poll    = command_emscripten_poll;
+   cmd->replier = emscripten_command_reply;
+   cmd->destroy = emscripten_command_free;
+
+   return cmd;
+}
+#endif
+
+
+
 bool command_get_config_param(command_t *cmd, const char* arg)
 {
    size_t _len;

command.h

@@ -329,11 +329,20 @@ struct rarch_state;
 bool command_event(enum event_command action, void *data);
 
 /* Constructors for the supported drivers */
+#ifdef HAVE_NETWORK_CMD
 command_t* command_network_new(uint16_t port);
+bool command_network_send(const char *cmd_);
+#endif
+#ifdef HAVE_STDIN_CMD
 command_t* command_stdin_new(void);
+#endif
+#ifdef LAKKA
 command_t* command_uds_new(void);
+#endif
+#ifdef EMSCRIPTEN
+command_t* command_emscripten_new(void);
+#endif
 
-bool command_network_send(const char *cmd_);
 
 void command_event_set_mixer_volume(
       settings_t *settings,

emscripten/library_platform_emscripten.js

@@ -12,7 +12,9 @@ var LibraryPlatformEmscripten = {
          RPE.powerState.dischargeTime = Number.isFinite(e.target.dischargingTime) ? e.target.dischargingTime : 0x7FFFFFFF;
          RPE.powerState.level = e.target.level;
          RPE.powerState.charging = e.target.charging;
-      }
+      },
+      command_queue:[],
+      command_reply_queue:[],
    },
 
    PlatformEmscriptenPowerStateInit: function() {
@@ -49,6 +51,15 @@ var LibraryPlatformEmscripten = {
    PlatformEmscriptenGetFreeMem: function() {
       if (!performance.memory) return 0;
       return (performance.memory.jsHeapSizeLimit || 0) - (performance.memory.usedJSHeapSize || 0);
+   },
+
+   $EmscriptenSendCommand__deps:["PlatformEmscriptenCommandRaiseFlag"],
+   $EmscriptenSendCommand: function(str) {
+      RPE.command_queue.push(str);
+      _PlatformEmscriptenCommandRaiseFlag();
+   },
+   $EmscriptenReceiveCommandReply: function() {
+      return RPE.command_reply_queue.shift();
    }
 };
 

frontend/drivers/platform_emscripten.c

@@ -91,6 +91,33 @@ bool PlatformEmscriptenPowerStateGetCharging(void);
 uint64_t PlatformEmscriptenGetTotalMem(void);
 uint64_t PlatformEmscriptenGetFreeMem(void);
 
+void PlatformEmscriptenCommandReply(const char *msg, size_t len) {
+  MAIN_THREAD_EM_ASM({
+      var message = UTF8ToString($0,$1);
+      RPE.command_reply_queue.push(message);
+    }, msg, len);
+}
+static bool command_flag = false;
+size_t PlatformEmscriptenCommandRead(char **into, size_t max_len) {
+  if(!command_flag) { return 0; }
+  return MAIN_THREAD_EM_ASM_INT({
+      var next_command = RPE.command_queue.shift();
+      var length = lengthBytesUTF8(next_command);
+      if(length > $2) {
+        console.error("[CMD] Command too long, skipping",next_command);
+        return 0;
+      }
+      stringToUTF8(next_command, $1, $2);
+      if(RPE.command_queue.length == 0) {
+        setValue($0, 0, 'i8');
+      }
+      return length;
+    }, &command_flag, into, max_len);
+}
+void PlatformEmscriptenCommandRaiseFlag() {
+  command_flag = true;
+}
+
 /* begin exported functions */
 
 /* saves and states */
@@ -350,32 +377,46 @@ void PlatformEmscriptenMountFilesystems(void *info) {
        */
       int max_line_len = 1024;
       printf("[FetchFS] read fetch manifest from %s\n",fetch_manifest);
-      FILE *file = fopen(fetch_manifest, O_RDONLY);
+      FILE *file = fopen(fetch_manifest, "r");
+      if(!file) {
+        printf("[FetchFS] missing manifest file\n");
+        abort();
+      }
       char *line = calloc(sizeof(char), max_line_len);
-      size_t len = 0;
+      size_t len = max_line_len;
       while (getline(&line, &len, file) != -1) {
          char *path = strstr(line, " ");
          backend_t fetch;
          int fd;
-         if (!path) {
-            printf("Manifest file has invalid line %s\n",line);
-            return;
+         if(len <= 2 || !path) {
+            printf("[FetchFS] Manifest file has invalid line %s\n",line);
+            continue;
          }
          *path = '\0';
          path += 1;
-         printf("Fetch %s from %s\n", path, line);
+         path[strcspn(path, "\r\n")] = '\0';
+         printf("[FetchFS] Fetch %s from %s\n", path, line);
          {
             char *parent = strdup(path);
             path_parent_dir(parent, strlen(parent));
             if(!path_mkdir(parent)) {
-               printf("mkdir error %d\n",errno);
+               printf("[FetchFS] mkdir error %d\n",errno);
                abort();
             }
             free(parent);
          }
-         fetch = wasmfs_create_fetch_backend(line, 8*1024*1024);
+         fetch = wasmfs_create_fetch_backend(line, 16*1024*1024);
+         if(!fetch) {
+           printf("[FetchFS] couldn't create fetch backend\n");
+           abort();
+         }
          fd = wasmfs_create_file(path, 0777, fetch);
+         if(!fd) {
+           printf("[FetchFS] couldn't create fetch file\n");
+           abort();
+         }
          close(fd);
+         len = max_line_len;
       }
       fclose(file);
       free(line);
@@ -433,7 +474,9 @@ void emscripten_bootup_mainloop(void *argptr) {
 int main(int argc, char *argv[])
 {
    args_t *args = calloc(sizeof(args_t), 1);
-
+   args->argc = argc;
+   args->argv = argv;
+
    PlatformEmscriptenWatchCanvasSize();
    PlatformEmscriptenPowerStateInit();
 

input/input_driver.c

@@ -5104,10 +5104,14 @@ void input_driver_init_command(input_driver_state_t *input_st,
    }
 #endif
 
-#ifdef HAVE_LAKKA
+#if defined(HAVE_LAKKA)
    if (!(input_st->command[2] = command_uds_new()))
       RARCH_ERR("Failed to initialize the UDS command interface.\n");
+#elif defined(EMSCRIPTEN)
+   if (!(input_st->command[2] = command_emscripten_new()))
+      RARCH_ERR("Failed to initialize the emscripten command interface.\n");
 #endif
+
 }
 
 void input_driver_deinit_command(input_driver_state_t *input_st)

pkg/emscripten/libretro-thread/libretro.js

@@ -14,64 +14,15 @@ var Module = {
    noImageDecoding: true,
    noAudioDecoding: true,
 
-   encoder: new TextEncoder(),
-   message_queue: [],
-   message_out: [],
-   message_accum: "",
-
-   retroArchSend: function(msg) {
-      let bytes = this.encoder.encode(msg + "\n");
-      this.message_queue.push([bytes, 0]);
-   },
-   retroArchRecv: function() {
-      let out = this.message_out.shift();
-      if (out == null && this.message_accum != "") {
-         out = this.message_accum;
-         this.message_accum = "";
-      }
-      return out;
-   },
+  retroArchSend: function(msg) {
+    this.EmscriptenSendCommand(msg);
+  },
+  retroArchRecv: function() {
+    return this.EmscriptenReceiveCommandReply();
+  },
    preRun: [
       function(module) {
          Module.ENV['OPFS'] = "/home/web_user/retroarch";
-      },
-      function(module) {
-         function stdin() {
-            // Return ASCII code of character, or null if no input
-            while (module.message_queue.length > 0) {
-               var msg = module.message_queue[0][0];
-               var index = module.message_queue[0][1];
-               if (index >= msg.length) {
-                  module.message_queue.shift();
-               } else {
-                  module.message_queue[0][1] = index + 1;
-                  // assumption: msg is a uint8array
-                  return msg[index];
-               }
-            }
-            return null;
-         }
-
-         function stdout(c) {
-            if (c == null) {
-               // flush
-               if (module.message_accum != "") {
-                  module.message_out.push(module.message_accum);
-                  module.message_accum = "";
-               }
-            } else {
-               let s = String.fromCharCode(c);
-               if (s == "\n") {
-                  if (module.message_accum != "") {
-                     module.message_out.push(module.message_accum);
-                     module.message_accum = "";
-                  }
-               } else {
-                  module.message_accum = module.message_accum + s;
-               }
-            }
-         }
-         module.FS.init(stdin, stdout);
       }
    ],
    postRun: [],

pkg/emscripten/libretro-thread/libretro.worker.js

@@ -60,7 +60,7 @@ onmessage = async (msg) => {
     }
     postMessage({command:"loaded_bundle", time:resp.headers.get("last-modified")});
   } else if(msg.data.command == "upload_file") {
-    await writeFile("/home/web_user/retroarch/userdata/content/"+msg.data.name, new Uint8Array(msg.data.data));
+    await writeFile("userdata/content/"+msg.data.name, new Uint8Array(msg.data.data));
     postMessage({command:"uploaded_file",name:msg.data.name});
   }
 }