Add JS infrastructure to ostensibly allow us to customize the wasm imports, which will hypothetically allow us to eliminate the dependency on EM_JS(), but the corresponding Emscripten glue-level feature currently breaks fatally with WASMFS builds so it's disabled.

FossilOrigin-Name: 88d9253b0db5494bf1c9b6d24f22524eeec856b89e64a66ffb30d945f0df21d3

9 files changed, 108 insertions, 23 deletions

diff --git a/ext/wasm/GNUmakefile b/ext/wasm/GNUmakefile
index ab687d1e4..94cb17a72 100644
--- a/ext/wasm/GNUmakefile
+++ b/ext/wasm/GNUmakefile
@@ -153,6 +153,10 @@ $(sqlite3-api.js): $(sqlite3-api.jses) $(MAKEFILE)
 		echo "/* END FILE: $$i */"; \
 	done > $@
 
+########################################################################
+# --post-js and --pre-js are emcc flags we use to append/prepend JS to
+# the generated emscripten module file.
+pre-js.js := $(dir.api)/pre-js.js
 post-js.js := post-js.js
 CLEAN_FILES += $(post-js.js)
 post-jses := \
@@ -167,8 +171,28 @@ $(post-js.js): $(post-jses) $(MAKEFILE)
 		echo "/* END FILE: $$i */"; \
 	done > $@
 extern-post-js.js := $(dir.api)/extern-post-js.js
-sqlite3.js.flags.--post-js := --post-js=$(post-js.js) --extern-post-js=$(extern-post-js.js)
-post-jses.deps := $(post-js.js) $(extern-post-js.js)
+extern-pre-js.js := $(dir.api)/extern-pre-js.js
+pre-post-common.flags := \
+  --post-js=$(post-js.js) \
+  --extern-post-js=$(extern-post-js.js) \
+  --extern-pre-js=$(extern-pre-js.js)
+pre-post-jses.deps := $(post-js.js) \
+  $(extern-post-js.js) $(extern-pre-js.js)
+########################################################################
+# call-make-pre-js creates rules for pre-js-$(1).js. $1 = the base
+# name of the JS file on whose behalf this pre-js is for.
+define call-make-pre-js
+pre-post-$(1).flags ?=
+pre-js-$(1).js: $$(pre-js.js) $$(MAKEFILE)
+	cp $$(pre-js.js) $$@
+	echo "Module[xInstantiateWasm].uri = '$(1).wasm';" >> $$@
+CLEAN_FILES += pre-js-$(1).js
+pre-post-$(1).deps := $$(pre-post-jses.deps) pre-js-$(1).js
+pre-post-$(1).flags += --pre-js=pre-js-$(1).js
+endef
+#$(error $(call call-make-pre-js,sqlite3-wasmfs))
+# /post-js and pre-js
+########################################################################
 
 ########################################################################
 # emcc flags for .c/.o/.wasm/.js.
@@ -202,7 +226,7 @@ emcc.exportedRuntimeMethods := \
 emcc.jsflags += $(emcc.exportedRuntimeMethods)
 emcc.jsflags += -sUSE_CLOSURE_COMPILER=0
 emcc.jsflags += -sIMPORTED_MEMORY
-emcc.environment := -sENVIRONMENT=web
+emcc.environment := -sENVIRONMENT=web,worker
 emcc.jsflags += -sALLOW_MEMORY_GROWTH
 # emcc: warning: USE_PTHREADS + ALLOW_MEMORY_GROWTH may run non-wasm code
 #       slowly, see https://github.com/WebAssembly/design/issues/1271
@@ -264,7 +288,6 @@ emcc.jsflags += -sWASM_BIGINT=$(emcc_enable_bigint)
 # code get confused and cannot load property (namely, the
 # sqlite3.worker.js generated in conjunction with -sWASMFS).
 sqlite3.js := sqlite3.js
-emcc.jsflags += $(sqlite3.js.flags.--post-js)
 sqlite3.wasm := sqlite3.wasm
 sqlite3-wasm.o := $(dir.api)/sqlite3-wasm.o
 $(sqlite3-wasm.o): emcc.cflags += $(SQLITE_OPT)
@@ -276,19 +299,25 @@ jaccwabyt_test.c := $(dir.jacc)/jaccwabyt_test.c
 # want to test the release builds with those apps, so we cannot simply
 # elide that file in release builds. That component is critical to the
 # VFS bindings so needs to be tested along with the core APIs.
-define WASM_C_COMPILE
+########################################################################
+# call-wasm-c-compile sets up build rules
+# for $1.o. $1 must be the name of a C file (with extension).
+define call-wasm-c-compile
 $(1).o := $$(subst .c,.o,$(1))
 sqlite3.wasm.obj += $$($(1).o)
 $$($(1).o): $$(MAKEFILE) $(1)
 	$$(emcc.bin) $$(emcc_opt_full) $$(emcc.flags) $$(emcc.cflags) -c $(1) -o $$@
 CLEAN_FILES += $$($(1).o)
 endef
-$(foreach c,$(sqlite3-wasm.c) $(jaccwabyt_test.c),$(eval $(call WASM_C_COMPILE,$(c))))
+$(foreach c,$(sqlite3-wasm.c) $(jaccwabyt_test.c),$(eval $(call call-wasm-c-compile,$(c))))
+$(eval $(call call-make-pre-js,sqlite3))
 $(sqlite3.js): $(MAKEFILE) $(sqlite3.wasm.obj) \
     EXPORTED_FUNCTIONS.api \
-    $(post-jses.deps)
+    $(pre-post-sqlite3.deps)
 	@echo "Building $@ ..."
-	$(emcc.bin) -o $@ $(emcc_opt_full) $(emcc.flags) $(emcc.jsflags) $(sqlite3.wasm.obj)
+	$(emcc.bin) -o $@ $(emcc_opt_full) $(emcc.flags) \
+    $(emcc.jsflags) $(pre-post-common.flags) $(pre-post-sqlite3.flags) \
+    $(sqlite3.wasm.obj)
 	chmod -x $(sqlite3.wasm)
 	$(maybe-wasm-strip) $(sqlite3.wasm)
 	@ls -la $@ $(sqlite3.wasm)
@@ -342,8 +371,8 @@ speedtest1-common.eflags += -sALLOW_TABLE_GROWTH
 speedtest1-common.eflags += -sDYNAMIC_EXECUTION=0
 speedtest1-common.eflags += --minify 0
 speedtest1-common.eflags += -sEXPORT_NAME=$(sqlite3.js.init-func)
-speedtest1-common.eflags += $(sqlite3.js.flags.--post-js)
 speedtest1-common.eflags += -sWASM_BIGINT=$(emcc_enable_bigint)
+speedtest1-common.eflags += $(pre-post-common.flags) 
 speedtest1.exit-runtime0 := -sEXIT_RUNTIME=0
 speedtest1.exit-runtime1 := -sEXIT_RUNTIME=1
 # Re -sEXIT_RUNTIME=1 vs 0: if it's 1 and speedtest1 crashes, we get
@@ -377,11 +406,14 @@ $(speedtest1.js): emcc.cflags+=
 # the latter (predictably) results in a slightly faster binary, but we're
 # close enough to the target speed requirements that the 500ms makes a
 # difference.
-$(speedtest1.js): $(MAKEFILE) $(speedtest1.cs) $(post-jses.deps) \
+$(eval $(call call-make-pre-js,speedtest1))
+$(speedtest1.js): $(MAKEFILE) $(speedtest1.cs) \
+    $(pre-post-speedtest1.deps) \
     EXPORTED_FUNCTIONS.speedtest1
 	@echo "Building $@ ..."
 	$(emcc.bin) \
         $(speedtest1.eflags) $(speedtest1-common.eflags) $(speedtest1.cflags) \
+        $(pre-post-speedtest1.flags) \
         $(SQLITE_OPT) \
         $(speedtest1.exit-runtime0) \
         -o $@ $(speedtest1.cs) -lm
diff --git a/ext/wasm/README.md b/ext/wasm/README.md
index f95001359..103295384 100644
--- a/ext/wasm/README.md
+++ b/ext/wasm/README.md
@@ -25,6 +25,7 @@ Those parts only need to be run once, but the SDK can be updated using:
 
 ```
 $ git pull
+$ ./emsdk install latest
 $ ./emsdk activate latest
 ```
 
diff --git a/ext/wasm/api/extern-post-js.js b/ext/wasm/api/extern-post-js.js
index acb54c3c9..25d2d1b32 100644
--- a/ext/wasm/api/extern-post-js.js
+++ b/ext/wasm/api/extern-post-js.js
@@ -1,4 +1,4 @@
-/* emscripten-js-addenda.js must be appended to the resulting sqlite3.js
+/* extern-post-js.js must be appended to the resulting sqlite3.js
    file. */
 (function(){
   /**
diff --git a/ext/wasm/api/extern-pre-js.js b/ext/wasm/api/extern-pre-js.js
new file mode 100644
index 000000000..26d066d2e
--- /dev/null
+++ b/ext/wasm/api/extern-pre-js.js
@@ -0,0 +1,4 @@
+/* extern-pre-js.js must be prepended to the resulting sqlite3.js
+   file. This file is currently only used for holding snippets during
+   test and development.
+*/
diff --git a/ext/wasm/api/pre-js.js b/ext/wasm/api/pre-js.js
new file mode 100644
index 000000000..f373fecec
--- /dev/null
+++ b/ext/wasm/api/pre-js.js
@@ -0,0 +1,40 @@
+Module['locateFile'] = function(path, prefix) {
+  return prefix + path;
+};
+
+/**
+   Bug warning: this xInstantiateWasm bit must remain disabled
+   until this bug is resolved or wasmfs won't work:
+
+   https://github.com/emscripten-core/emscripten/issues/17951
+*/
+const xInstantiateWasm = 1
+      ? 'emscripten-bug-17951'
+      : 'instantiateWasm';
+Module[xInstantiateWasm] = function callee(imports,onSuccess){
+  imports.foo = function(){};
+  console.warn("instantiateWasm() uri =",callee.uri, self.location.href);
+  const wfetch = ()=>fetch(callee.uri, {credentials: 'same-origin'});
+  const loadWasm = WebAssembly.instantiateStreaming
+        ? function loadWasmStreaming(){
+          return WebAssembly.instantiateStreaming(wfetch(), imports)
+            .then((arg)=>onSuccess(arg.instance, arg.module));
+        }
+        : function loadWasmOldSchool(){ // Safari < v15
+          return wfetch()
+            .then(response => response.arrayBuffer())
+            .then(bytes => WebAssembly.instantiate(bytes, imports))
+            .then((arg)=>onSuccess(arg.instance, arg.module));
+        };
+  loadWasm();
+  return {};
+};
+/*
+  It is literally impossible to get the name of a Worker's own script,
+  so impossible to derive X.wasm from script name X.js. Thus we need,
+  at build-time, to redifine Module['instantiateWasm'].uri by
+  appending it to a build-specific copy of this file with the name of
+  the wasm file. This is apparently why Emscripten hard-codes the name of
+  the wasm file into their glue scripts.
+*/
+Module[xInstantiateWasm].uri = 'sqlite3.wasm';
diff --git a/ext/wasm/common/whwasmutil.js b/ext/wasm/common/whwasmutil.js
index 662978b20..8b6dbdd83 100644
--- a/ext/wasm/common/whwasmutil.js
+++ b/ext/wasm/common/whwasmutil.js
@@ -1538,7 +1538,7 @@ self.WhWasmUtilInstaller = function(target){
 
    - `onload(loadResult,config)`: optional callback. The first
      argument is the result object from
-     WebAssembly.instanitate[Streaming](). The 2nd is the config
+     WebAssembly.instantiate[Streaming](). The 2nd is the config
      object passed to this function. Described in more detail below.
 
    - `imports`: optional imports object for
diff --git a/ext/wasm/demo-123.js b/ext/wasm/demo-123.js
index 00ea1f5bc..37dc7a7af 100644
--- a/ext/wasm/demo-123.js
+++ b/ext/wasm/demo-123.js
@@ -21,6 +21,7 @@
   */
   let logHtml;
   if(self.window === self /* UI thread */){
+    console.log("Running demo from main UI thread.");
     logHtml = function(cssClass,...args){
       const ln = document.createElement('div');
       if(cssClass) ln.classList.add(cssClass);
@@ -28,6 +29,7 @@
       document.body.append(ln);
     };
   }else{ /* Worker thread */
+    console.log("Running demo from Worker thread.");
     logHtml = function(cssClass,...args){
       postMessage({
         type:'log',
diff --git a/ext/wasm/fiddle.make b/ext/wasm/fiddle.make
index c3892263a..6ccf8e029 100644
--- a/ext/wasm/fiddle.make
+++ b/ext/wasm/fiddle.make
@@ -57,10 +57,13 @@ SOAP.js := sqlite3-opfs-async-proxy.js
 $(dir.fiddle)/$(SOAP.js): $(SOAP.js)
 	cp $< $@
 
+$(eval $(call call-make-pre-js,fiddle-module))
 $(fiddle-module.js): $(MAKEFILE) $(MAKEFILE.fiddle) \
     EXPORTED_FUNCTIONS.fiddle EXPORTED_RUNTIME_METHODS.fiddle \
-    $(fiddle.cs) $(post-jses.deps) $(dir.fiddle)/$(SOAP.js)
-	$(emcc.bin) -o $@ $(fiddle.emcc-flags) $(fiddle.cs)
+    $(fiddle.cs) $(pre-post-fiddle.deps) $(dir.fiddle)/$(SOAP.js)
+	$(emcc.bin) -o $@ $(fiddle.emcc-flags) \
+    $(pre-post-common.flags) $(pre-post-fiddle.flags) \
+    $(fiddle.cs)
 	$(maybe-wasm-strip) $(fiddle-module.wasm)
 	gzip < $@ > $@.gz
 	gzip < $(fiddle-module.wasm) > $(fiddle-module.wasm).gz
diff --git a/ext/wasm/wasmfs.make b/ext/wasm/wasmfs.make
index b93f2ab0c..fa8320e58 100644
--- a/ext/wasm/wasmfs.make
+++ b/ext/wasm/wasmfs.make
@@ -22,7 +22,7 @@ sqlite3-wasmfs.flags =
 ########################################################################
 # emcc flags for .c/.o.
 sqlite3-wasmfs.cflags :=
-sqlite3-wasmfs.cflags += -std=c99 -fPIC -g
+sqlite3-wasmfs.cflags += -std=c99 -fPIC
 sqlite3-wasmfs.cflags += -pthread
 sqlite3-wasmfs.cflags += -I. -I.. -I$(dir.top)
 sqlite3-wasmfs.cflags += $(SQLITE_OPT) -DSQLITE_WASM_WASMFS
@@ -57,7 +57,6 @@ sqlite3-wasmfs.jsflags += -sIMPORTED_MEMORY
 #sqlite3-wasmfs.jsflags += -sTOTAL_STACK=4194304
 sqlite3-wasmfs.jsflags += -sEXPORT_NAME=$(sqlite3.js.init-func)
 sqlite3-wasmfs.jsflags += -sGLOBAL_BASE=4096 # HYPOTHETICALLY keep func table indexes from overlapping w/ heap addr.
-sqlite3-wasmfs.jsflags += $(sqlite3.js.flags.--post-js)
 #sqlite3-wasmfs.jsflags += -sFILESYSTEM=0 # only for experimentation. sqlite3 needs the FS API
 #                                Perhaps the wasmfs build doesn't?
 #sqlite3-wasmfs.jsflags += -sABORTING_MALLOC
@@ -70,20 +69,22 @@ sqlite3-wasmfs.jsflags += -sLLD_REPORT_UNDEFINED
 sqlite3-wasmfs.jsflags += -sMEMORY64=0
 sqlite3-wasmfs.jsflags += -sINITIAL_MEMORY=128450560
 sqlite3-wasmfs.fsflags := -pthread -sWASMFS -sPTHREAD_POOL_SIZE=2 -sENVIRONMENT=web,worker
+# -sPTHREAD_POOL_SIZE values of 2 or higher trigger that bug.
 sqlite3-wasmfs.jsflags += $(sqlite3-wasmfs.fsflags)
-speedtest1-common.eflags += -sEXPORTED_FUNCTIONS=@$(dir.wasm)/EXPORTED_FUNCTIONS.speedtest1
 #sqlite3-wasmfs.jsflags += -sALLOW_MEMORY_GROWTH
 #^^^ using ALLOW_MEMORY_GROWTH produces a warning from emcc:
 #   USE_PTHREADS + ALLOW_MEMORY_GROWTH may run non-wasm code slowly,
 #   see https://github.com/WebAssembly/design/issues/1271 [-Wpthreads-mem-growth]
 sqlite3-wasmfs.jsflags += -sWASM_BIGINT=$(emcc_enable_bigint)
-
+$(eval $(call call-make-pre-js,sqlite3-wasmfs))
+sqlite3-wasmfs.jsflags += $(pre-post-common.flags) $(pre-post-sqlite3-wasmfs.flags)
 $(sqlite3-wasmfs.js): $(sqlite3-wasmfs.wasm.c) $(sqlite3-wasm.c) $(sqlite3-wasmfs.extra.c) \
-    EXPORTED_FUNCTIONS.api $(sqlite3-wasm.js) $(MAKEFILE) $(MAKEFILE.wasmfs) \
-    $(post-jses.deps)
+    EXPORTED_FUNCTIONS.api $(MAKEFILE) $(MAKEFILE.wasmfs) \
+    $(pre-post-sqlite3-wasmfs.deps)
 	@echo "Building $@ ..."
 	$(emcc.bin) -o $@ $(emcc_opt_full) $(emcc.flags) \
-      $(sqlite3-wasmfs.cflags) $(sqlite3-wasmfs.jsflags) $(sqlite3-wasmfs.wasm.c) $(sqlite3-wasmfs.extra.c)
+      $(sqlite3-wasmfs.cflags) $(sqlite3-wasmfs.jsflags) \
+     $(sqlite3-wasmfs.wasm.c) $(sqlite3-wasmfs.extra.c)
 	chmod -x $(sqlite3-wasmfs.wasm)
 	$(maybe-wasm-strip) $(sqlite3-wasmfs.wasm)
 	@ls -la $@ $(sqlite3-wasmfs.wasm)
@@ -99,13 +100,15 @@ speedtest1-wasmfs.js := speedtest1-wasmfs.js
 speedtest1-wasmfs.wasm := $(subst .js,.wasm,$(speedtest1-wasmfs.js))
 speedtest1-wasmfs.eflags := $(sqlite3-wasmfs.fsflags)
 speedtest1-wasmfs.eflags += $(SQLITE_OPT) -DSQLITE_WASM_WASMFS
-$(speedtest1-wasmfs.js): $(MAKEFILE) $(MAKEFILE.wasmfs)
-#$(speedtest1-wasmfs.js): $(sqlite3-wasmfs.js)
+$(eval $(call call-make-pre-js,speedtest1-wasmfs))
 $(speedtest1-wasmfs.js): $(speedtest1.cs) $(sqlite3-wasmfs.js) \
+  $(MAKEFILE) $(MAKEFILE.wasmfs) \
+  $(pre-post-speedtest1-wasmfs.deps) \
   EXPORTED_FUNCTIONS.speedtest1
 	@echo "Building $@ ..."
 	$(emcc.bin) \
         $(speedtest1-wasmfs.eflags) $(speedtest1-common.eflags) \
+        $(pre-post-speedtest1-wasmfs.flags) \
         $(speedtest1.cflags) \
         $(sqlite3-wasmfs.cflags) \
         -o $@ $(speedtest1.cs) -lm