Adding upstream version 3.40.1.upstream/3.40.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 379 insertions, 0 deletions

diff --git a/ext/wasm/fiddle/fiddle-worker.js b/ext/wasm/fiddle/fiddle-worker.js
new file mode 100644
index 0000000..a60b79a
--- /dev/null
+++ b/ext/wasm/fiddle/fiddle-worker.js
@@ -0,0 +1,379 @@
+/*
+  2022-05-20
+
+  The author disclaims copyright to this source code.  In place of a
+  legal notice, here is a blessing:
+
+  *   May you do good and not evil.
+  *   May you find forgiveness for yourself and forgive others.
+  *   May you share freely, never taking more than you give.
+
+  ***********************************************************************
+
+  This is the JS Worker file for the sqlite3 fiddle app. It loads the
+  sqlite3 wasm module and offers access to the db via the Worker
+  message-passing interface.
+
+  Forewarning: this API is still very much Under Construction and
+  subject to any number of changes as experience reveals what those
+  need to be.
+
+  Because we can have only a single message handler, as opposed to an
+  arbitrary number of discrete event listeners like with DOM elements,
+  we have to define a lower-level message API. Messages abstractly
+  look like:
+
+  { type: string, data: type-specific value }
+
+  Where 'type' is used for dispatching and 'data' is a
+  'type'-dependent value.
+
+  The 'type' values expected by each side of the main/worker
+  connection vary. The types are described below but subject to
+  change at any time as this experiment evolves.
+
+  Workers-to-Main types
+
+  - stdout, stderr: indicate stdout/stderr output from the wasm
+    layer. The data property is the string of the output, noting
+    that the emscripten binding emits these one line at a time. Thus,
+    if a C-side puts() emits multiple lines in a single call, the JS
+    side will see that as multiple calls. Example:
+
+    {type:'stdout', data: 'Hi, world.'}
+
+  - module: Status text. This is intended to alert the main thread
+    about module loading status so that, e.g., the main thread can
+    update a progress widget and DTRT when the module is finished
+    loading and available for work. Status messages come in the form
+    
+    {type:'module', data:{
+        type:'status',
+        data: {text:string|null, step:1-based-integer}
+    }
+
+    with an incrementing step value for each subsequent message. When
+    the module loading is complete, a message with a text value of
+    null is posted.
+
+  - working: data='start'|'end'. Indicates that work is about to be
+    sent to the module or has just completed. This can be used, e.g.,
+    to disable UI elements which should not be activated while work
+    is pending. Example:
+
+    {type:'working', data:'start'}
+
+  Main-to-Worker types:
+
+  - shellExec: data=text to execute as if it had been entered in the
+    sqlite3 CLI shell app (as opposed to sqlite3_exec()). This event
+    causes the worker to emit a 'working' event (data='start') before
+    it starts and a 'working' event (data='end') when it finished. If
+    called while work is currently being executed it emits stderr
+    message instead of doing actual work, as the underlying db cannot
+    handle concurrent tasks. Example:
+
+    {type:'shellExec', data: 'select * from sqlite_master'}
+
+  - More TBD as the higher-level db layer develops.
+*/
+
+/*
+  Apparent browser(s) bug: console messages emitted may be duplicated
+  in the console, even though they're provably only run once. See:
+
+  https://stackoverflow.com/questions/49659464
+
+  Noting that it happens in Firefox as well as Chrome. Harmless but
+  annoying.
+*/
+"use strict";
+(function(){
+  /**
+     Posts a message in the form {type,data}. If passed more than 2
+     args, the 3rd must be an array of "transferable" values to pass
+     as the 2nd argument to postMessage(). */
+  const wMsg =
+        (type,data,transferables)=>{
+          postMessage({type, data}, transferables || []);
+        };
+  const stdout = (...args)=>wMsg('stdout', args);
+  const stderr = (...args)=>wMsg('stderr', args);
+  const toss = (...args)=>{
+    throw new Error(args.join(' '));
+  };
+  const fixmeOPFS = "(FIXME: won't work with OPFS-over-sqlite3_vfs.)";
+  let sqlite3 /* gets assigned when the wasm module is loaded */;
+
+  self.onerror = function(/*message, source, lineno, colno, error*/) {
+    const err = arguments[4];
+    if(err && 'ExitStatus'==err.name){
+      /* This is relevant for the sqlite3 shell binding but not the
+         lower-level binding. */
+      fiddleModule.isDead = true;
+      stderr("FATAL ERROR:", err.message);
+      stderr("Restarting the app requires reloading the page.");
+      wMsg('error', err);
+    }
+    console.error(err);
+    fiddleModule.setStatus('Exception thrown, see JavaScript console: '+err);
+  };
+
+  const Sqlite3Shell = {
+    /** Returns the name of the currently-opened db. */
+    dbFilename: function f(){
+      if(!f._) f._ = sqlite3.wasm.xWrap('fiddle_db_filename', "string", ['string']);
+      return f._(0);
+    },
+    dbHandle: function f(){
+      if(!f._) f._ = sqlite3.wasm.xWrap("fiddle_db_handle", "sqlite3*");
+      return f._();
+    },
+    dbIsOpfs: function f(){
+      return sqlite3.opfs && sqlite3.capi.sqlite3_js_db_uses_vfs(
+        this.dbHandle(), "opfs"
+      );
+    },
+    runMain: function f(){
+      if(f.argv) return 0===f.argv.rc;
+      const dbName = "/fiddle.sqlite3";
+      f.argv = [
+        'sqlite3-fiddle.wasm',
+        '-bail', '-safe',
+        dbName
+        /* Reminder: because of how we run fiddle, we have to ensure
+           that any argv strings passed to its main() are valid until
+           the wasm environment shuts down. */
+      ];
+      const capi = sqlite3.capi, wasm = sqlite3.wasm;
+      /* We need to call sqlite3_shutdown() in order to avoid numerous
+         legitimate warnings from the shell about it being initialized
+         after sqlite3_initialize() has been called. This means,
+         however, that any initialization done by the JS code may need
+         to be re-done (e.g.  re-registration of dynamically-loaded
+         VFSes). We need a more generic approach to running such
+         init-level code. */
+      capi.sqlite3_shutdown();
+      f.argv.pArgv = wasm.allocMainArgv(f.argv);
+      f.argv.rc = wasm.exports.fiddle_main(
+        f.argv.length, f.argv.pArgv
+      );
+      if(f.argv.rc){
+        stderr("Fatal error initializing sqlite3 shell.");
+        fiddleModule.isDead = true;
+        return false;
+      }
+      stdout("SQLite version", capi.sqlite3_libversion(),
+             capi.sqlite3_sourceid().substr(0,19));
+      stdout('Welcome to the "fiddle" shell.');
+      if(sqlite3.opfs){
+        stdout("\nOPFS is available. To open a persistent db, use:\n\n",
+               "  .open file:name?vfs=opfs\n\nbut note that some",
+               "features (e.g. upload) do not yet work with OPFS.");
+        sqlite3.opfs.registerVfs();
+      }
+      stdout('\nEnter ".help" for usage hints.');
+      this.exec([ // initialization commands...
+        '.nullvalue NULL',
+        '.headers on'
+      ].join('\n'));
+      return true;
+    },
+    /**
+       Runs the given text through the shell as if it had been typed
+       in by a user. Fires a working/start event before it starts and
+       working/end event when it finishes.
+    */
+    exec: function f(sql){
+      if(!f._){
+        if(!this.runMain()) return;
+        f._ = sqlite3.wasm.xWrap('fiddle_exec', null, ['string']);
+      }
+      if(fiddleModule.isDead){
+        stderr("shell module has exit()ed. Cannot run SQL.");
+        return;
+      }
+      wMsg('working','start');
+      try {
+        if(f._running){
+          stderr('Cannot run multiple commands concurrently.');
+        }else if(sql){
+          if(Array.isArray(sql)) sql = sql.join('');
+          f._running = true;
+          f._(sql);
+        }
+      }finally{
+        delete f._running;
+        wMsg('working','end');
+      }
+    },
+    resetDb: function f(){
+      if(!f._) f._ = sqlite3.wasm.xWrap('fiddle_reset_db', null);
+      stdout("Resetting database.");
+      f._();
+      stdout("Reset",this.dbFilename());
+    },
+    /* Interrupt can't work: this Worker is tied up working, so won't get the
+       interrupt event which would be needed to perform the interrupt. */
+    interrupt: function f(){
+      if(!f._) f._ = sqlite3.wasm.xWrap('fiddle_interrupt', null);
+      stdout("Requesting interrupt.");
+      f._();
+    }
+  };
+  
+  self.onmessage = function f(ev){
+    ev = ev.data;
+    if(!f.cache){
+      f.cache = {
+        prevFilename: null
+      };
+    }
+    //console.debug("worker: onmessage.data",ev);
+    switch(ev.type){
+        case 'shellExec': Sqlite3Shell.exec(ev.data); return;
+        case 'db-reset': Sqlite3Shell.resetDb(); return;
+        case 'interrupt': Sqlite3Shell.interrupt(); return;
+          /** Triggers the export of the current db. Fires an
+              event in the form:
+
+              {type:'db-export',
+                data:{
+                  filename: name of db,
+                  buffer: contents of the db file (Uint8Array),
+                  error: on error, a message string and no buffer property.
+                }
+              }
+          */
+        case 'db-export': {
+          const fn = Sqlite3Shell.dbFilename();
+          stdout("Exporting",fn+".");
+          const fn2 = fn ? fn.split(/[/\\]/).pop() : null;
+          try{
+            if(!fn2) toss("DB appears to be closed.");
+            const buffer = sqlite3.capi.sqlite3_js_db_export(
+              Sqlite3Shell.dbHandle()
+            );
+            wMsg('db-export',{filename: fn2, buffer: buffer.buffer}, [buffer.buffer]);
+          }catch(e){
+            console.error("Export failed:",e);
+            /* Post a failure message so that UI elements disabled
+               during the export can be re-enabled. */
+            wMsg('db-export',{
+              filename: fn,
+              error: e.message
+            });
+          }
+          return;
+        }
+        case 'open': {
+          /* Expects: {
+               buffer: ArrayBuffer | Uint8Array,
+               filename: the filename for the db. Any dir part is
+                         stripped.
+              }
+          */
+          const opt = ev.data;
+          let buffer = opt.buffer;
+          stderr('open():',fixmeOPFS);
+          if(buffer instanceof ArrayBuffer){
+            buffer = new Uint8Array(buffer);
+          }else if(!(buffer instanceof Uint8Array)){
+            stderr("'open' expects {buffer:Uint8Array} containing an uploaded db.");
+            return;
+          }
+          const fn = (
+            opt.filename
+              ? opt.filename.split(/[/\\]/).pop().replace('"','_')
+              : ("db-"+((Math.random() * 10000000) | 0)+
+                 "-"+((Math.random() * 10000000) | 0)+".sqlite3")
+          );
+          try {
+            /* We cannot delete the existing db file until the new one
+               is installed, which means that we risk overflowing our
+               quota (if any) by having both the previous and current
+               db briefly installed in the virtual filesystem. */
+            const fnAbs = '/'+fn;
+            const oldName = Sqlite3Shell.dbFilename();
+            if(oldName && oldName===fnAbs){
+              /* We cannot create the replacement file while the current file
+                 is opened, nor does the shell have a .close command, so we
+                 must temporarily switch to another db... */
+              Sqlite3Shell.exec('.open :memory:');
+              fiddleModule.FS.unlink(fnAbs);
+            }
+            fiddleModule.FS.createDataFile("/", fn, buffer, true, true);
+            Sqlite3Shell.exec('.open "'+fnAbs+'"');
+            if(oldName && oldName!==fnAbs){
+              try{fiddleModule.fsUnlink(oldName)}
+              catch(e){/*ignored*/}
+            }
+            stdout("Replaced DB with",fn+".");
+          }catch(e){
+            stderr("Error installing db",fn+":",e.message);
+          }
+          return;
+        }
+    };
+    console.warn("Unknown fiddle-worker message type:",ev);
+  };
+  
+  /**
+     emscripten module for use with build mode -sMODULARIZE.
+  */
+  const fiddleModule = {
+    print: stdout,
+    printErr: stderr,
+    /**
+       Intercepts status updates from the emscripting module init
+       and fires worker events with a type of 'status' and a
+       payload of:
+
+       {
+       text: string | null, // null at end of load process
+       step: integer // starts at 1, increments 1 per call
+       }
+
+       We have no way of knowing in advance how many steps will
+       be processed/posted, so creating a "percentage done" view is
+       not really practical. One can be approximated by giving it a
+       current value of message.step and max value of message.step+1,
+       though.
+
+       When work is finished, a message with a text value of null is
+       submitted.
+
+       After a message with text==null is posted, the module may later
+       post messages about fatal problems, e.g. an exit() being
+       triggered, so it is recommended that UI elements for posting
+       status messages not be outright removed from the DOM when
+       text==null, and that they instead be hidden until/unless
+       text!=null.
+    */
+    setStatus: function f(text){
+      if(!f.last) f.last = { step: 0, text: '' };
+      else if(text === f.last.text) return;
+      f.last.text = text;
+      wMsg('module',{
+        type:'status',
+        data:{step: ++f.last.step, text: text||null}
+      });
+    }
+  };
+
+  importScripts('fiddle-module.js'+self.location.search);
+  /**
+     initFiddleModule() is installed via fiddle-module.js due to
+     building with:
+
+     emcc ... -sMODULARIZE=1 -sEXPORT_NAME=initFiddleModule
+  */
+  sqlite3InitModule(fiddleModule).then((_sqlite3)=>{
+    sqlite3 = _sqlite3;
+    const dbVfs = sqlite3.wasm.xWrap('fiddle_db_vfs', "*", ['string']);
+    fiddleModule.fsUnlink = (fn)=>{
+      return sqlite3.wasm.sqlite3_wasm_vfs_unlink(dbVfs(0), fn);
+    };
+    wMsg('fiddle-ready');
+  })/*then()*/;
+})();