mirror of
https://github.com/sqlite/sqlite.git
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Initial build of kvvfs in wasm. It loads but cannot find the VFS for as-yet-unknown reasons (sqlite3 shell works fine), and most APIs throw "null function or function signature mismatch" from deep within wasm, presumably as a side effect of the "missing" VFS.
FossilOrigin-Name: 1a2f24a0bdfc6eaae478916b8f4f9c6b63ead9964534fc2951fb4e995ffe61f1
This commit is contained in:
stephan
@ -262,6 +262,7 @@ all: $(sqlite3.js)
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# End main Emscripten-based module build
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########################################################################
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include kvvfs.make
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########################################################################
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# fiddle_remote is the remote destination for the fiddle app. It
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82
ext/wasm/kvvfs.make
Normal file
82
ext/wasm/kvvfs.make
Normal file
@ -0,0 +1,82 @@
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#!/usr/bin/make
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#^^^^ help emacs select makefile mode
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#
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# This is a sub-make for building a standalone kvvfs-based
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# sqlite3.wasm. It is intended to be "include"d from the main
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# GNUMakefile.
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#
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# Notable potential TODOs:
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#
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# - Trim down a custom sqlite3-api.js for this build. We can elimate
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# the jaccwabyt dependency, for example, because this build won't
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# make use of the VFS bits. Similarly, we can eliminate or replace
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# parts of the OO1 API, or provide a related API which manages
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# singletons of the localStorage/sessionStorage instances.
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#
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########################################################################
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MAKEFILE.kvvfs := $(lastword $(MAKEFILE_LIST))
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kvvfs.js := sqlite3-kvvfs.js
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kvvfs.wasm := sqlite3-kvvfs.wasm
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kvvfs.wasm.c := $(dir.api)/sqlite3-wasm.c
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CLEAN_FILES += $(kvvfs.js) $(kvvfs.wasm)
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########################################################################
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# emcc flags for .c/.o/.wasm.
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kvvfs.flags =
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#kvvfs.flags += -v # _very_ loud but also informative about what it's doing
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########################################################################
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# emcc flags for .c/.o.
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kvvfs.cflags :=
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kvvfs.cflags += -std=c99 -fPIC
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kvvfs.cflags += -I. -I$(dir.top)
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kvvfs.cflags += -DSQLITE_OS_KV=1 $(SQLITE_OPT)
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########################################################################
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# emcc flags specific to building the final .js/.wasm file...
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kvvfs.jsflags := -fPIC
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kvvfs.jsflags += --no-entry
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kvvfs.jsflags += -sENVIRONMENT=web
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kvvfs.jsflags += -sMODULARIZE
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kvvfs.jsflags += -sSTRICT_JS
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kvvfs.jsflags += -sDYNAMIC_EXECUTION=0
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kvvfs.jsflags += -sNO_POLYFILL
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kvvfs.jsflags += -sEXPORTED_FUNCTIONS=@$(dir.api)/EXPORTED_FUNCTIONS.sqlite3-api
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kvvfs.jsflags += -sEXPORTED_RUNTIME_METHODS=FS,wasmMemory,allocateUTF8OnStack
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# wasmMemory ==> for -sIMPORTED_MEMORY
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# allocateUTF8OnStack ==> kvvfs internals
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kvvfs.jsflags += -sUSE_CLOSURE_COMPILER=0
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kvvfs.jsflags += -sIMPORTED_MEMORY
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#kvvfs.jsflags += -sINITIAL_MEMORY=13107200
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#kvvfs.jsflags += -sTOTAL_STACK=4194304
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kvvfs.jsflags += -sEXPORT_NAME=sqlite3InitModule
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kvvfs.jsflags += -sGLOBAL_BASE=4096 # HYPOTHETICALLY keep func table indexes from overlapping w/ heap addr.
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kvvfs.jsflags += --post-js=$(post-js.js)
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#kvvfs.jsflags += -sFILESYSTEM=0 # only for experimentation. sqlite3 needs the FS API
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# Perhaps the kvvfs build doesn't?
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#kvvfs.jsflags += -sABORTING_MALLOC
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kvvfs.jsflags += -sALLOW_MEMORY_GROWTH
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kvvfs.jsflags += -sALLOW_TABLE_GROWTH
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kvvfs.jsflags += -Wno-limited-postlink-optimizations
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# ^^^^^ it likes to warn when we have "limited optimizations" via the -g3 flag.
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kvvfs.jsflags += -sERROR_ON_UNDEFINED_SYMBOLS=0
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kvvfs.jsflags += -sLLD_REPORT_UNDEFINED
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#kvvfs.jsflags += --import-undefined
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kvvfs.jsflags += -sMEMORY64=0
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ifneq (0,$(enable_bigint))
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kvvfs.jsflags += -sWASM_BIGINT
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endif
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$(kvvfs.js): $(MAKEFILE) $(MAKEFILE.kvvfs) $(kvvfs.wasm.c) \
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EXPORTED_FUNCTIONS.api \
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$(post-js.js)
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$(emcc.bin) -o $@ $(emcc_opt) $(emcc.flags) $(kvvfs.cflags) $(kvvfs.jsflags) $(kvvfs.wasm.c)
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chmod -x $(kvvfs.wasm)
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ifneq (,$(wasm-strip))
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$(wasm-strip) $(kvvfs.wasm)
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endif
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@ls -la $@ $(kvvfs.wasm)
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kvvfs: $(kvvfs.js)
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34
ext/wasm/kvvfs1.html
Normal file
34
ext/wasm/kvvfs1.html
Normal file
@ -0,0 +1,34 @@
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<!doctype html>
|
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<html lang="en-us">
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<head>
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<meta charset="utf-8">
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<link rel="shortcut icon" href="data:image/x-icon;," type="image/x-icon">
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<link rel="stylesheet" href="common/emscripten.css"/>
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<link rel="stylesheet" href="common/testing.css"/>
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<title>sqlite3-kvvfs.js tests</title>
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</head>
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<body>
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<header id='titlebar'><span>sqlite3-kvvfs.js tests</span></header>
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<!-- emscripten bits -->
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<figure id="module-spinner">
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<div class="spinner"></div>
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<div class='center'><strong>Initializing app...</strong></div>
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<div class='center'>
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On a slow internet connection this may take a moment. If this
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message displays for "a long time", intialization may have
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failed and the JavaScript console may contain clues as to why.
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</div>
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</figure>
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<div class="emscripten" id="module-status">Downloading...</div>
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<div class="emscripten">
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<progress value="0" max="100" id="module-progress" hidden='1'></progress>
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</div><!-- /emscripten bits -->
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<div>Everything on this page happens in the dev console.</div>
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<hr>
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<div id='test-output'></div>
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<script src="sqlite3-kvvfs.js"></script>
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<script src="common/SqliteTestUtil.js"></script>
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<script src="kvvfs1.js"></script>
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</body>
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</html>
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52
ext/wasm/kvvfs1.js
Normal file
52
ext/wasm/kvvfs1.js
Normal file
@ -0,0 +1,52 @@
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/*
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||||
2022-09-12
|
||||
|
||||
The author disclaims copyright to this source code. In place of a
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||||
legal notice, here is a blessing:
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||||
|
||||
* May you do good and not evil.
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||||
* May you find forgiveness for yourself and forgive others.
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||||
* May you share freely, never taking more than you give.
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||||
|
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***********************************************************************
|
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A basic test script for sqlite3-kvvfs.wasm. This file must be run in
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main JS thread and sqlite3-kvvfs.js must have been loaded before it.
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*/
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'use strict';
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(function(){
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const T = self.SqliteTestUtil;
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const toss = function(...args){throw new Error(args.join(' '))};
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const debug = console.debug.bind(console);
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const eOutput = document.querySelector('#test-output');
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const log = console.log.bind(console)
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const logHtml = function(...args){
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log.apply(this, args);
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const ln = document.createElement('div');
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ln.append(document.createTextNode(args.join(' ')));
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eOutput.append(ln);
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||||
};
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||||
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const runTests = function(Module){
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//log("Module",Module);
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const sqlite3 = Module.sqlite3,
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capi = sqlite3.capi,
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oo = sqlite3.oo1,
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wasm = capi.wasm;
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log("Loaded module:",capi.sqlite3_libversion(), capi.sqlite3_sourceid());
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log("Build options:",wasm.compileOptionUsed());
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self.S = sqlite3;
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log("vfs(null) =",capi.sqlite3_vfs_find(null))
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log("vfs('kvvfs') =",capi.sqlite3_vfs_find('kvvfs'))
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//const db = new oo.DB("session");
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||||
|
||||
log("Init done. Proceed from the dev console.");
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||||
};
|
||||
|
||||
sqlite3InitModule(self.sqlite3TestModule).then(function(theModule){
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console.warn("Installing Emscripten module as global EM for dev console access.");
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||||
self.EM = theModule;
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runTests(theModule);
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});
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||||
})();
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19
manifest
19
manifest
@ -1,5 +1,5 @@
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||||
C Improved\scomments\sin\sos_kv.c.\s\sBetter\snames\sfor\sthe\skey/value\sname\sspaces.
|
||||
D 2022-09-10T18:38:21.976
|
||||
C Initial\sbuild\sof\skvvfs\sin\swasm.\sIt\sloads\sbut\scannot\sfind\sthe\sVFS\sfor\sas-yet-unknown\sreasons\s(sqlite3\sshell\sworks\sfine),\sand\smost\sAPIs\sthrow\s"null\sfunction\sor\sfunction\ssignature\smismatch"\sfrom\sdeep\swithin\swasm,\spresumably\sas\sa\sside\seffect\sof\sthe\s"missing"\sVFS.
|
||||
D 2022-09-12T12:39:28.819
|
||||
F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
|
||||
F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
|
||||
F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
|
||||
@ -474,7 +474,7 @@ F ext/userauth/user-auth.txt e6641021a9210364665fe625d067617d03f27b04
|
||||
F ext/userauth/userauth.c 7f00cded7dcaa5d47f54539b290a43d2e59f4b1eb5f447545fa865f002fc80cb
|
||||
F ext/wasm/EXPORTED_FUNCTIONS.fiddle 7fb73f7150ab79d83bb45a67d257553c905c78cd3d693101699243f36c5ae6c3
|
||||
F ext/wasm/EXPORTED_RUNTIME_METHODS.fiddle a004bd5eeeda6d3b28d16779b7f1a80305bfe009dfc7f0721b042967f0d39d02
|
||||
F ext/wasm/GNUmakefile 5359a37fc13b68fad2259228590450339a0c59687744edd0db7bb93d3b1ae2b1
|
||||
F ext/wasm/GNUmakefile 12a672ab9125dc860457c2853f7651b98517e424d7a0e9714c89b28c5ff73800
|
||||
F ext/wasm/README.md 4b00ae7c7d93c4591251245f0996a319e2651361013c98d2efb0b026771b7331
|
||||
F ext/wasm/api/EXPORTED_FUNCTIONS.sqlite3-api c5eaceabb9e759aaae7d3101a4a3e542f96ab2c99d89a80ce20ec18c23115f33
|
||||
F ext/wasm/api/EXPORTED_RUNTIME_METHODS.sqlite3-api 1ec3c73e7d66e95529c3c64ac3de2470b0e9e7fbf7a5b41261c367cf4f1b7287
|
||||
@ -502,6 +502,9 @@ F ext/wasm/jaccwabyt/jaccwabyt.js 99b424b4d467d4544e82615b58e2fe07532a898540bf9d
|
||||
F ext/wasm/jaccwabyt/jaccwabyt.md 447cc02b598f7792edaa8ae6853a7847b8178a18ed356afacbdbf312b2588106
|
||||
F ext/wasm/jaccwabyt/jaccwabyt_test.c 39e4b865a33548f943e2eb9dd0dc8d619a80de05d5300668e9960fff30d0d36f
|
||||
F ext/wasm/jaccwabyt/jaccwabyt_test.exports 5ff001ef975c426ffe88d7d8a6e96ec725e568d2c2307c416902059339c06f19
|
||||
F ext/wasm/kvvfs.make 7cc9cf10e744c3ba523c3eaf5c4af47028f3a5bb76db304ea8044a9b2a9d496f
|
||||
F ext/wasm/kvvfs1.html 2acb241a6110a4ec581adbf07a23d5fc2ef9c7142aa9d60856732a102abc5016
|
||||
F ext/wasm/kvvfs1.js 461d571234244bd682725f1dd73195b1d9a7eabdd57c0181ff41dc7c55252313
|
||||
F ext/wasm/testing1.html 0bf3ff224628c1f1e3ed22a2dc1837c6c73722ad8c0ad9c8e6fb9e6047667231
|
||||
F ext/wasm/testing1.js cba7134901a965743fa9289d82447ab71de4690b1ee5d06f6cb83e8b569d7943
|
||||
F ext/wasm/testing2.html 73e5048e666fd6fb28b6e635677a9810e1e139c599ddcf28d687c982134b92b8
|
||||
@ -571,7 +574,7 @@ F src/notify.c 89a97dc854c3aa62ad5f384ef50c5a4a11d70fcc69f86de3e991573421130ed6
|
||||
F src/os.c 0eb831ba3575af5277e47f4edd14fdfc90025c67eb25ce5cda634518d308d4e9
|
||||
F src/os.h 1ff5ae51d339d0e30d8a9d814f4b8f8e448169304d83a7ed9db66a65732f3e63
|
||||
F src/os_common.h b2f4707a603e36811d9b1a13278bffd757857b85
|
||||
F src/os_kv.c c658ddfb433b982afb3d12d133117e8db9eee11af33db41c30a6f30375f9b99a
|
||||
F src/os_kv.c a188e92dac693b1c1b512d93b0c4dc85c1baad11e322b01121f87057996e4d11
|
||||
F src/os_setup.h 0711dbc4678f3ac52d7fe736951b6384a0615387c4ba5135a4764e4e31f4b6a6
|
||||
F src/os_unix.c 102f7e5c5b59c18ea3dbc929dc3be8acb3afc0e0b6ad572e032335c9c27f44f1
|
||||
F src/os_win.c e9454cb141908e8eef2102180bad353a36480612d5b736e4c2bd5777d9b25a34
|
||||
@ -2001,8 +2004,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
|
||||
F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
|
||||
F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
|
||||
F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
|
||||
P f6632e69c2ec1a7ddc4e51f3567e3bc082ee94a6dd51fdafdc0c3bf386a32d4c
|
||||
R 8cd4482ba17a8f6c143ea61b8462f46c
|
||||
U drh
|
||||
Z 81846bec91bdcab04bc60c9c032d039e
|
||||
P 8e1652a3856765c9146cc2a7e3b598a2dc7dc84c556b35eab9a35184514384b9
|
||||
R 87fbf09a4dec22281b7328e04378fb76
|
||||
U stephan
|
||||
Z bc0b4e3041260a10b10ef1c5f11f1ba3
|
||||
# Remove this line to create a well-formed Fossil manifest.
|
||||
|
||||
@ -1 +1 @@
|
||||
8e1652a3856765c9146cc2a7e3b598a2dc7dc84c556b35eab9a35184514384b9
|
||||
1a2f24a0bdfc6eaae478916b8f4f9c6b63ead9964534fc2951fb4e995ffe61f1
|
||||
206
src/os_kv.c
206
src/os_kv.c
@ -166,10 +166,6 @@ static sqlite3_io_methods kvvfs_jrnl_io_methods = {
|
||||
/* Forward declarations for the low-level storage engine
|
||||
*/
|
||||
#define KVSTORAGE_KEY_SZ 32
|
||||
static int kvstorageWrite(const char*, const char *zKey, const char *zData);
|
||||
static int kvstorageDelete(const char*, const char *zKey);
|
||||
static int kvstorageRead(const char*, const char *zKey, char *zBuf, int nBuf);
|
||||
|
||||
|
||||
/* Expand the key name with an appropriate prefix and put the result
|
||||
** zKeyOut[]. The zKeyOut[] buffer is assumed to hold at least
|
||||
@ -183,6 +179,207 @@ static void kvstorageMakeKey(
|
||||
sqlite3_snprintf(KVSTORAGE_KEY_SZ, zKeyOut, "kvvfs-%s-%s", zClass, zKeyIn);
|
||||
}
|
||||
|
||||
#ifdef __EMSCRIPTEN__
|
||||
/* Provide Emscripten-based impls of kvstorageWrite/Read/Delete()... */
|
||||
#include <emscripten.h>
|
||||
#include <emscripten/console.h>
|
||||
|
||||
/*
|
||||
** WASM_KEEP is identical to EMSCRIPTEN_KEEPALIVE but is not
|
||||
** Emscripten-specific. It explicitly includes marked functions for
|
||||
** export into the target wasm file without requiring explicit listing
|
||||
** of those functions in Emscripten's -sEXPORTED_FUNCTIONS=... list
|
||||
** (or equivalent in other build platforms). Any function with neither
|
||||
** this attribute nor which is listed as an explicit export will not
|
||||
** be exported from the wasm file (but may still be used internally
|
||||
** within the wasm file).
|
||||
**
|
||||
** The functions in this file (sqlite3-wasm.c) which require exporting
|
||||
** are marked with this flag. They may also be added to any explicit
|
||||
** build-time export list but need not be. All of these APIs are
|
||||
** intended for use only within the project's own JS/WASM code, and
|
||||
** not by client code, so an argument can be made for reducing their
|
||||
** visibility by not including them in any build-time export lists.
|
||||
**
|
||||
** 2022-09-11: it's not yet _proven_ that this approach works in
|
||||
** non-Emscripten builds. If not, such builds will need to export
|
||||
** those using the --export=... wasm-ld flag (or equivalent). As of
|
||||
** this writing we are tied to Emscripten for various reasons
|
||||
** and cannot test the library with other build environments.
|
||||
*/
|
||||
#define WASM_KEEP __attribute__((used,visibility("default")))
|
||||
/*
|
||||
** An internal level of indirection for accessing the static
|
||||
** kvstorageMakeKey() from EM_JS()-generated functions. This must be
|
||||
** made available for export via Emscripten but is not intended to be
|
||||
** used from client code. If called with a NULL zKeyOut it is a no-op.
|
||||
** It returns KVSTORAGE_KEY_SZ, so JS code (which cannot see that
|
||||
** constant) may call it with NULL arguments to get the size of the
|
||||
** allocation they'll need for a kvvfs key.
|
||||
**
|
||||
** Maintenance reminder: Emscripten will install this in the Module
|
||||
** init scope and will prefix its name with "_".
|
||||
*/
|
||||
WASM_KEEP
|
||||
int sqlite3_wasm__kvvfsMakeKey(const char *zClass, const char *zKeyIn,
|
||||
char *zKeyOut){
|
||||
if( 0!=zKeyOut ) kvstorageMakeKey(zClass, zKeyIn, zKeyOut);
|
||||
return KVSTORAGE_KEY_SZ;
|
||||
}
|
||||
/*
|
||||
** Internal helper for kvstorageWrite/Read/Delete() which creates a
|
||||
** storage key for the given zClass/zKeyIn combination. Returns a
|
||||
** pointer to the key: a C string allocated on the WASM stack, or 0 if
|
||||
** allocation fails. It is up to the caller to save/restore the stack
|
||||
** before/after this operation.
|
||||
*/
|
||||
EM_JS(const char *, kvstorageMakeKeyOnJSStack,
|
||||
(const char *zClass, const char *zKeyIn),{
|
||||
if( 0==zClass || 0==zKeyIn) return 0;
|
||||
const zXKey = stackAlloc(_sqlite3_wasm__kvvfsMakeKey(0,0,0));
|
||||
if(zXKey) _sqlite3_wasm__kvvfsMakeKey(zClass, zKeyIn, zXKey);
|
||||
return zXKey;
|
||||
});
|
||||
|
||||
/*
|
||||
** JS impl of kvstorageWrite(). Main docs are in the C impl. This impl
|
||||
** writes zData to the global sessionStorage (if zClass starts with
|
||||
** 's') or localStorage, using a storage key derived from zClass and
|
||||
** zKey.
|
||||
*/
|
||||
EM_JS(int, kvstorageWrite,
|
||||
(const char *zClass, const char *zKey, const char *zData),{
|
||||
const stack = stackSave();
|
||||
try {
|
||||
const zXKey = kvstorageMakeKeyOnJSStack(zClass,zKey);
|
||||
if(!zXKey) return 1/*OOM*/;
|
||||
const jKey = UTF8ToString(zXKey);
|
||||
/**
|
||||
We could simplify this function and eliminate the
|
||||
kvstorageMakeKey() symbol acrobatics if we'd simply hard-code
|
||||
the key algo into the 3 functions which need it:
|
||||
|
||||
const jKey = "kvvfs-"+UTF8ToString(zClass)+"-"+UTF8ToString(zKey);
|
||||
*/
|
||||
((115/*=='s'*/===getValue(zClass))
|
||||
? sessionStorage : localStorage).setItem(jKey, UTF8ToString(zData));
|
||||
}catch(e){
|
||||
console.error("kvstorageWrite()",e);
|
||||
return 1; // Can't access SQLITE_xxx from here
|
||||
}finally{
|
||||
stackRestore(stack);
|
||||
}
|
||||
return 0;
|
||||
});
|
||||
|
||||
/*
|
||||
** JS impl of kvstorageDelete(). Main docs are in the C impl. This
|
||||
** impl generates a key derived from zClass and zKey, and removes the
|
||||
** matching entry (if any) from global sessionStorage (if zClass
|
||||
** starts with 's') or localStorage.
|
||||
*/
|
||||
EM_JS(int, kvstorageDelete,
|
||||
(const char *zClass, const char *zKey),{
|
||||
const stack = stackSave();
|
||||
try {
|
||||
const zXKey = kvstorageMakeKeyOnJSStack(zClass,zKey);
|
||||
if(!zXKey) return 1/*OOM*/;
|
||||
_sqlite3_wasm__kvvfsMakeKey(zClass, zKey, zXKey);
|
||||
const jKey = UTF8ToString(zXKey);
|
||||
((115/*=='s'*/===getValue(zClass))
|
||||
? sessionStorage : localStorage).removeItem(jKey);
|
||||
}catch(e){
|
||||
console.error("kvstorageDelete()",e);
|
||||
return 1;
|
||||
}finally{
|
||||
stackRestore(stack);
|
||||
}
|
||||
return 0;
|
||||
});
|
||||
|
||||
/*
|
||||
** JS impl of kvstorageRead(). Main docs are in the C impl. This impl
|
||||
** reads its data from the global sessionStorage (if zClass starts
|
||||
** with 's') or localStorage, using a storage key derived from zClass
|
||||
** and zKey.
|
||||
*/
|
||||
EM_JS(int, kvstorageRead,
|
||||
(const char *zClass, const char *zKey, char *zBuf, int nBuf),{
|
||||
const stack = stackSave();
|
||||
try {
|
||||
const zXKey = kvstorageMakeKeyOnJSStack(zClass,zKey);
|
||||
if(!zXKey) return -3/*OOM*/;
|
||||
const jKey = UTF8ToString(zXKey);
|
||||
const jV = ((115/*=='s'*/===getValue(zClass))
|
||||
? sessionStorage : localStorage).getItem(jKey);
|
||||
if(!jV) return -1;
|
||||
const nV = jV.length /* Note that we are relying 100% on v being
|
||||
ASCII so that jV.length is equal to the
|
||||
C-string's byte length. */;
|
||||
if(nBuf<=0) return nV;
|
||||
else if(1===nBuf){
|
||||
setValue(zBuf, 0);
|
||||
return nV;
|
||||
}
|
||||
const zV = allocateUTF8OnStack(jV);
|
||||
if(nBuf > nV + 1) nBuf = nV + 1;
|
||||
HEAPU8.copyWithin(zBuf, zV, zV + nBuf - 1);
|
||||
setValue( zBuf + nBuf - 1, 0 );
|
||||
return nBuf - 1;
|
||||
}catch(e){
|
||||
console.error("kvstorageRead()",e);
|
||||
return -2;
|
||||
}finally{
|
||||
stackRestore(stack);
|
||||
}
|
||||
});
|
||||
|
||||
/*
|
||||
** This function exists for (1) WASM testing purposes and (2) as a
|
||||
** hook to get Emscripten to export several EM_JS()-generated
|
||||
** functions (if we don't reference them from exported C functions
|
||||
** then they get stripped away at build time). It is not part of the
|
||||
** public API and its signature and semantics may change at any time.
|
||||
** It's not even part of the private API, for that matter - it's part
|
||||
** of the Emscripten C/JS/WASM glue.
|
||||
*/
|
||||
WASM_KEEP
|
||||
int sqlite3__wasm_emjs_kvvfs(int whichOp){
|
||||
int rc = 0;
|
||||
const char * zClass =
|
||||
"sezzion" /*don't collide with "session" records!*/;
|
||||
const char * zKey = "hello";
|
||||
switch( whichOp ){
|
||||
case 0: break;
|
||||
case 1:
|
||||
kvstorageWrite(zClass, zKey, "world");
|
||||
break;
|
||||
case 2: {
|
||||
char buffer[128] = {0};
|
||||
char * zBuf = &buffer[0];
|
||||
rc = kvstorageRead(zClass, zKey, zBuf, (int)sizeof(buffer));
|
||||
emscripten_console_logf("kvstorageRead()=%d %s\n", rc, zBuf);
|
||||
break;
|
||||
}
|
||||
case 3:
|
||||
kvstorageDelete(zClass, zKey);
|
||||
break;
|
||||
case 4:
|
||||
kvstorageMakeKeyOnJSStack(0,0);
|
||||
break;
|
||||
default: break;
|
||||
}
|
||||
return rc;
|
||||
}
|
||||
|
||||
#undef WASM_KEEP
|
||||
#else /* end ifdef __EMSCRIPTEN__ */
|
||||
/* Forward declarations for the low-level storage engine
|
||||
*/
|
||||
static int kvstorageWrite(const char*, const char *zKey, const char *zData);
|
||||
static int kvstorageDelete(const char*, const char *zKey);
|
||||
static int kvstorageRead(const char*, const char *zKey, char *zBuf, int nBuf);
|
||||
|
||||
/* Write content into a key. zClass is the particular namespace of the
|
||||
** underlying key/value store to use - either "local" or "session".
|
||||
**
|
||||
@ -277,6 +474,7 @@ static int kvstorageRead(
|
||||
return (int)n;
|
||||
}
|
||||
}
|
||||
#endif /* ifdef __EMSCRIPTEN__ */
|
||||
|
||||
/****** Utility subroutines ************************************************/
|
||||
|
||||
|
||||
Reference in New Issue
Block a user