mirror of
https://github.com/tursodatabase/libsql.git
synced 2024-11-23 19:06:15 +00:00
719 lines
27 KiB
JavaScript
719 lines
27 KiB
JavaScript
/*
|
|
** 2022-11-30
|
|
**
|
|
** 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 file installs sqlite3.vfs, and object which exists to assist
|
|
in the creation of JavaScript implementations of sqlite3_vfs, along
|
|
with its virtual table counterpart, sqlite3.vtab.
|
|
*/
|
|
'use strict';
|
|
globalThis.sqlite3ApiBootstrap.initializers.push(function(sqlite3){
|
|
const wasm = sqlite3.wasm, capi = sqlite3.capi, toss = sqlite3.util.toss3;
|
|
const vfs = Object.create(null), vtab = Object.create(null);
|
|
|
|
const StructBinder = sqlite3.StructBinder
|
|
/* we require a local alias b/c StructBinder is removed from the sqlite3
|
|
object during the final steps of the API cleanup. */;
|
|
sqlite3.vfs = vfs;
|
|
sqlite3.vtab = vtab;
|
|
|
|
const sii = capi.sqlite3_index_info;
|
|
/**
|
|
If n is >=0 and less than this.$nConstraint, this function
|
|
returns either a WASM pointer to the 0-based nth entry of
|
|
this.$aConstraint (if passed a truthy 2nd argument) or an
|
|
sqlite3_index_info.sqlite3_index_constraint object wrapping that
|
|
address (if passed a falsy value or no 2nd argument). Returns a
|
|
falsy value if n is out of range.
|
|
*/
|
|
sii.prototype.nthConstraint = function(n, asPtr=false){
|
|
if(n<0 || n>=this.$nConstraint) return false;
|
|
const ptr = this.$aConstraint + (
|
|
sii.sqlite3_index_constraint.structInfo.sizeof * n
|
|
);
|
|
return asPtr ? ptr : new sii.sqlite3_index_constraint(ptr);
|
|
};
|
|
|
|
/**
|
|
Works identically to nthConstraint() but returns state from
|
|
this.$aConstraintUsage, so returns an
|
|
sqlite3_index_info.sqlite3_index_constraint_usage instance
|
|
if passed no 2nd argument or a falsy 2nd argument.
|
|
*/
|
|
sii.prototype.nthConstraintUsage = function(n, asPtr=false){
|
|
if(n<0 || n>=this.$nConstraint) return false;
|
|
const ptr = this.$aConstraintUsage + (
|
|
sii.sqlite3_index_constraint_usage.structInfo.sizeof * n
|
|
);
|
|
return asPtr ? ptr : new sii.sqlite3_index_constraint_usage(ptr);
|
|
};
|
|
|
|
/**
|
|
If n is >=0 and less than this.$nOrderBy, this function
|
|
returns either a WASM pointer to the 0-based nth entry of
|
|
this.$aOrderBy (if passed a truthy 2nd argument) or an
|
|
sqlite3_index_info.sqlite3_index_orderby object wrapping that
|
|
address (if passed a falsy value or no 2nd argument). Returns a
|
|
falsy value if n is out of range.
|
|
*/
|
|
sii.prototype.nthOrderBy = function(n, asPtr=false){
|
|
if(n<0 || n>=this.$nOrderBy) return false;
|
|
const ptr = this.$aOrderBy + (
|
|
sii.sqlite3_index_orderby.structInfo.sizeof * n
|
|
);
|
|
return asPtr ? ptr : new sii.sqlite3_index_orderby(ptr);
|
|
};
|
|
|
|
/**
|
|
Installs a StructBinder-bound function pointer member of the
|
|
given name and function in the given StructType target object.
|
|
|
|
It creates a WASM proxy for the given function and arranges for
|
|
that proxy to be cleaned up when tgt.dispose() is called. Throws
|
|
on the slightest hint of error, e.g. tgt is-not-a StructType,
|
|
name does not map to a struct-bound member, etc.
|
|
|
|
As a special case, if the given function is a pointer, then
|
|
`wasm.functionEntry()` is used to validate that it is a known
|
|
function. If so, it is used as-is with no extra level of proxying
|
|
or cleanup, else an exception is thrown. It is legal to pass a
|
|
value of 0, indicating a NULL pointer, with the caveat that 0
|
|
_is_ a legal function pointer in WASM but it will not be accepted
|
|
as such _here_. (Justification: the function at address zero must
|
|
be one which initially came from the WASM module, not a method we
|
|
want to bind to a virtual table or VFS.)
|
|
|
|
This function returns a proxy for itself which is bound to tgt
|
|
and takes 2 args (name,func). That function returns the same
|
|
thing as this one, permitting calls to be chained.
|
|
|
|
If called with only 1 arg, it has no side effects but returns a
|
|
func with the same signature as described above.
|
|
|
|
ACHTUNG: because we cannot generically know how to transform JS
|
|
exceptions into result codes, the installed functions do no
|
|
automatic catching of exceptions. It is critical, to avoid
|
|
undefined behavior in the C layer, that methods mapped via
|
|
this function do not throw. The exception, as it were, to that
|
|
rule is...
|
|
|
|
If applyArgcCheck is true then each JS function (as opposed to
|
|
function pointers) gets wrapped in a proxy which asserts that it
|
|
is passed the expected number of arguments, throwing if the
|
|
argument count does not match expectations. That is only intended
|
|
for dev-time usage for sanity checking, and will leave the C
|
|
environment in an undefined state.
|
|
*/
|
|
const installMethod = function callee(
|
|
tgt, name, func, applyArgcCheck = callee.installMethodArgcCheck
|
|
){
|
|
if(!(tgt instanceof StructBinder.StructType)){
|
|
toss("Usage error: target object is-not-a StructType.");
|
|
}else if(!(func instanceof Function) && !wasm.isPtr(func)){
|
|
toss("Usage errror: expecting a Function or WASM pointer to one.");
|
|
}
|
|
if(1===arguments.length){
|
|
return (n,f)=>callee(tgt, n, f, applyArgcCheck);
|
|
}
|
|
if(!callee.argcProxy){
|
|
callee.argcProxy = function(tgt, funcName, func,sig){
|
|
return function(...args){
|
|
if(func.length!==arguments.length){
|
|
toss("Argument mismatch for",
|
|
tgt.structInfo.name+"::"+funcName
|
|
+": Native signature is:",sig);
|
|
}
|
|
return func.apply(this, args);
|
|
}
|
|
};
|
|
/* An ondispose() callback for use with
|
|
StructBinder-created types. */
|
|
callee.removeFuncList = function(){
|
|
if(this.ondispose.__removeFuncList){
|
|
this.ondispose.__removeFuncList.forEach(
|
|
(v,ndx)=>{
|
|
if('number'===typeof v){
|
|
try{wasm.uninstallFunction(v)}
|
|
catch(e){/*ignore*/}
|
|
}
|
|
/* else it's a descriptive label for the next number in
|
|
the list. */
|
|
}
|
|
);
|
|
delete this.ondispose.__removeFuncList;
|
|
}
|
|
};
|
|
}/*static init*/
|
|
const sigN = tgt.memberSignature(name);
|
|
if(sigN.length<2){
|
|
toss("Member",name,"does not have a function pointer signature:",sigN);
|
|
}
|
|
const memKey = tgt.memberKey(name);
|
|
const fProxy = (applyArgcCheck && !wasm.isPtr(func))
|
|
/** This middle-man proxy is only for use during development, to
|
|
confirm that we always pass the proper number of
|
|
arguments. We know that the C-level code will always use the
|
|
correct argument count. */
|
|
? callee.argcProxy(tgt, memKey, func, sigN)
|
|
: func;
|
|
if(wasm.isPtr(fProxy)){
|
|
if(fProxy && !wasm.functionEntry(fProxy)){
|
|
toss("Pointer",fProxy,"is not a WASM function table entry.");
|
|
}
|
|
tgt[memKey] = fProxy;
|
|
}else{
|
|
const pFunc = wasm.installFunction(fProxy, tgt.memberSignature(name, true));
|
|
tgt[memKey] = pFunc;
|
|
if(!tgt.ondispose || !tgt.ondispose.__removeFuncList){
|
|
tgt.addOnDispose('ondispose.__removeFuncList handler',
|
|
callee.removeFuncList);
|
|
tgt.ondispose.__removeFuncList = [];
|
|
}
|
|
tgt.ondispose.__removeFuncList.push(memKey, pFunc);
|
|
}
|
|
return (n,f)=>callee(tgt, n, f, applyArgcCheck);
|
|
}/*installMethod*/;
|
|
installMethod.installMethodArgcCheck = false;
|
|
|
|
/**
|
|
Installs methods into the given StructType-type instance. Each
|
|
entry in the given methods object must map to a known member of
|
|
the given StructType, else an exception will be triggered. See
|
|
installMethod() for more details, including the semantics of the
|
|
3rd argument.
|
|
|
|
As an exception to the above, if any two or more methods in the
|
|
2nd argument are the exact same function, installMethod() is
|
|
_not_ called for the 2nd and subsequent instances, and instead
|
|
those instances get assigned the same method pointer which is
|
|
created for the first instance. This optimization is primarily to
|
|
accommodate special handling of sqlite3_module::xConnect and
|
|
xCreate methods.
|
|
|
|
On success, returns its first argument. Throws on error.
|
|
*/
|
|
const installMethods = function(
|
|
structInstance, methods, applyArgcCheck = installMethod.installMethodArgcCheck
|
|
){
|
|
const seen = new Map /* map of <Function, memberName> */;
|
|
for(const k of Object.keys(methods)){
|
|
const m = methods[k];
|
|
const prior = seen.get(m);
|
|
if(prior){
|
|
const mkey = structInstance.memberKey(k);
|
|
structInstance[mkey] = structInstance[structInstance.memberKey(prior)];
|
|
}else{
|
|
installMethod(structInstance, k, m, applyArgcCheck);
|
|
seen.set(m, k);
|
|
}
|
|
}
|
|
return structInstance;
|
|
};
|
|
|
|
/**
|
|
Equivalent to calling installMethod(this,...arguments) with a
|
|
first argument of this object. If called with 1 or 2 arguments
|
|
and the first is an object, it's instead equivalent to calling
|
|
installMethods(this,...arguments).
|
|
*/
|
|
StructBinder.StructType.prototype.installMethod = function callee(
|
|
name, func, applyArgcCheck = installMethod.installMethodArgcCheck
|
|
){
|
|
return (arguments.length < 3 && name && 'object'===typeof name)
|
|
? installMethods(this, ...arguments)
|
|
: installMethod(this, ...arguments);
|
|
};
|
|
|
|
/**
|
|
Equivalent to calling installMethods() with a first argument
|
|
of this object.
|
|
*/
|
|
StructBinder.StructType.prototype.installMethods = function(
|
|
methods, applyArgcCheck = installMethod.installMethodArgcCheck
|
|
){
|
|
return installMethods(this, methods, applyArgcCheck);
|
|
};
|
|
|
|
/**
|
|
Uses sqlite3_vfs_register() to register this
|
|
sqlite3.capi.sqlite3_vfs. This object must have already been
|
|
filled out properly. If the first argument is truthy, the VFS is
|
|
registered as the default VFS, else it is not.
|
|
|
|
On success, returns this object. Throws on error.
|
|
*/
|
|
capi.sqlite3_vfs.prototype.registerVfs = function(asDefault=false){
|
|
if(!(this instanceof sqlite3.capi.sqlite3_vfs)){
|
|
toss("Expecting a sqlite3_vfs-type argument.");
|
|
}
|
|
const rc = capi.sqlite3_vfs_register(this, asDefault ? 1 : 0);
|
|
if(rc){
|
|
toss("sqlite3_vfs_register(",this,") failed with rc",rc);
|
|
}
|
|
if(this.pointer !== capi.sqlite3_vfs_find(this.$zName)){
|
|
toss("BUG: sqlite3_vfs_find(vfs.$zName) failed for just-installed VFS",
|
|
this);
|
|
}
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
A wrapper for installMethods() or registerVfs() to reduce
|
|
installation of a VFS and/or its I/O methods to a single
|
|
call.
|
|
|
|
Accepts an object which contains the properties "io" and/or
|
|
"vfs", each of which is itself an object with following properties:
|
|
|
|
- `struct`: an sqlite3.StructType-type struct. This must be a
|
|
populated (except for the methods) object of type
|
|
sqlite3_io_methods (for the "io" entry) or sqlite3_vfs (for the
|
|
"vfs" entry).
|
|
|
|
- `methods`: an object mapping sqlite3_io_methods method names
|
|
(e.g. 'xClose') to JS implementations of those methods. The JS
|
|
implementations must be call-compatible with their native
|
|
counterparts.
|
|
|
|
For each of those object, this function passes its (`struct`,
|
|
`methods`, (optional) `applyArgcCheck`) properties to
|
|
installMethods().
|
|
|
|
If the `vfs` entry is set then:
|
|
|
|
- Its `struct` property's registerVfs() is called. The
|
|
`vfs` entry may optionally have an `asDefault` property, which
|
|
gets passed as the argument to registerVfs().
|
|
|
|
- If `struct.$zName` is falsy and the entry has a string-type
|
|
`name` property, `struct.$zName` is set to the C-string form of
|
|
that `name` value before registerVfs() is called. That string
|
|
gets added to the on-dispose state of the struct.
|
|
|
|
On success returns this object. Throws on error.
|
|
*/
|
|
vfs.installVfs = function(opt){
|
|
let count = 0;
|
|
const propList = ['io','vfs'];
|
|
for(const key of propList){
|
|
const o = opt[key];
|
|
if(o){
|
|
++count;
|
|
installMethods(o.struct, o.methods, !!o.applyArgcCheck);
|
|
if('vfs'===key){
|
|
if(!o.struct.$zName && 'string'===typeof o.name){
|
|
o.struct.addOnDispose(
|
|
o.struct.$zName = wasm.allocCString(o.name)
|
|
);
|
|
}
|
|
o.struct.registerVfs(!!o.asDefault);
|
|
}
|
|
}
|
|
}
|
|
if(!count) toss("Misuse: installVfs() options object requires at least",
|
|
"one of:", propList);
|
|
return this;
|
|
};
|
|
|
|
/**
|
|
Internal factory function for xVtab and xCursor impls.
|
|
*/
|
|
const __xWrapFactory = function(methodName,StructType){
|
|
return function(ptr,removeMapping=false){
|
|
if(0===arguments.length) ptr = new StructType;
|
|
if(ptr instanceof StructType){
|
|
//T.assert(!this.has(ptr.pointer));
|
|
this.set(ptr.pointer, ptr);
|
|
return ptr;
|
|
}else if(!wasm.isPtr(ptr)){
|
|
sqlite3.SQLite3Error.toss("Invalid argument to",methodName+"()");
|
|
}
|
|
let rc = this.get(ptr);
|
|
if(removeMapping) this.delete(ptr);
|
|
return rc;
|
|
}.bind(new Map);
|
|
};
|
|
|
|
/**
|
|
A factory function which implements a simple lifetime manager for
|
|
mappings between C struct pointers and their JS-level wrappers.
|
|
The first argument must be the logical name of the manager
|
|
(e.g. 'xVtab' or 'xCursor'), which is only used for error
|
|
reporting. The second must be the capi.XYZ struct-type value,
|
|
e.g. capi.sqlite3_vtab or capi.sqlite3_vtab_cursor.
|
|
|
|
Returns an object with 4 methods: create(), get(), unget(), and
|
|
dispose(), plus a StructType member with the value of the 2nd
|
|
argument. The methods are documented in the body of this
|
|
function.
|
|
*/
|
|
const StructPtrMapper = function(name, StructType){
|
|
const __xWrap = __xWrapFactory(name,StructType);
|
|
/**
|
|
This object houses a small API for managing mappings of (`T*`)
|
|
to StructType<T> objects, specifically within the lifetime
|
|
requirements of sqlite3_module methods.
|
|
*/
|
|
return Object.assign(Object.create(null),{
|
|
/** The StructType object for this object's API. */
|
|
StructType,
|
|
/**
|
|
Creates a new StructType object, writes its `pointer`
|
|
value to the given output pointer, and returns that
|
|
object. Its intended usage depends on StructType:
|
|
|
|
sqlite3_vtab: to be called from sqlite3_module::xConnect()
|
|
or xCreate() implementations.
|
|
|
|
sqlite3_vtab_cursor: to be called from xOpen().
|
|
|
|
This will throw if allocation of the StructType instance
|
|
fails or if ppOut is not a pointer-type value.
|
|
*/
|
|
create: (ppOut)=>{
|
|
const rc = __xWrap();
|
|
wasm.pokePtr(ppOut, rc.pointer);
|
|
return rc;
|
|
},
|
|
/**
|
|
Returns the StructType object previously mapped to the
|
|
given pointer using create(). Its intended usage depends
|
|
on StructType:
|
|
|
|
sqlite3_vtab: to be called from sqlite3_module methods which
|
|
take a (sqlite3_vtab*) pointer _except_ for
|
|
xDestroy()/xDisconnect(), in which case unget() or dispose().
|
|
|
|
sqlite3_vtab_cursor: to be called from any sqlite3_module methods
|
|
which take a `sqlite3_vtab_cursor*` argument except xClose(),
|
|
in which case use unget() or dispose().
|
|
|
|
Rule to remember: _never_ call dispose() on an instance
|
|
returned by this function.
|
|
*/
|
|
get: (pCObj)=>__xWrap(pCObj),
|
|
/**
|
|
Identical to get() but also disconnects the mapping between the
|
|
given pointer and the returned StructType object, such that
|
|
future calls to this function or get() with the same pointer
|
|
will return the undefined value. Its intended usage depends
|
|
on StructType:
|
|
|
|
sqlite3_vtab: to be called from sqlite3_module::xDisconnect() or
|
|
xDestroy() implementations or in error handling of a failed
|
|
xCreate() or xConnect().
|
|
|
|
sqlite3_vtab_cursor: to be called from xClose() or during
|
|
cleanup in a failed xOpen().
|
|
|
|
Calling this method obligates the caller to call dispose() on
|
|
the returned object when they're done with it.
|
|
*/
|
|
unget: (pCObj)=>__xWrap(pCObj,true),
|
|
/**
|
|
Works like unget() plus it calls dispose() on the
|
|
StructType object.
|
|
*/
|
|
dispose: (pCObj)=>{
|
|
const o = __xWrap(pCObj,true);
|
|
if(o) o.dispose();
|
|
}
|
|
});
|
|
};
|
|
|
|
/**
|
|
A lifetime-management object for mapping `sqlite3_vtab*`
|
|
instances in sqlite3_module methods to capi.sqlite3_vtab
|
|
objects.
|
|
|
|
The API docs are in the API-internal StructPtrMapper().
|
|
*/
|
|
vtab.xVtab = StructPtrMapper('xVtab', capi.sqlite3_vtab);
|
|
|
|
/**
|
|
A lifetime-management object for mapping `sqlite3_vtab_cursor*`
|
|
instances in sqlite3_module methods to capi.sqlite3_vtab_cursor
|
|
objects.
|
|
|
|
The API docs are in the API-internal StructPtrMapper().
|
|
*/
|
|
vtab.xCursor = StructPtrMapper('xCursor', capi.sqlite3_vtab_cursor);
|
|
|
|
/**
|
|
Convenience form of creating an sqlite3_index_info wrapper,
|
|
intended for use in xBestIndex implementations. Note that the
|
|
caller is expected to call dispose() on the returned object
|
|
before returning. Though not _strictly_ required, as that object
|
|
does not own the pIdxInfo memory, it is nonetheless good form.
|
|
*/
|
|
vtab.xIndexInfo = (pIdxInfo)=>new capi.sqlite3_index_info(pIdxInfo);
|
|
|
|
/**
|
|
Given an error object, this function returns
|
|
sqlite3.capi.SQLITE_NOMEM if (e instanceof
|
|
sqlite3.WasmAllocError), else it returns its
|
|
second argument. Its intended usage is in the methods
|
|
of a sqlite3_vfs or sqlite3_module:
|
|
|
|
```
|
|
try{
|
|
let rc = ...
|
|
return rc;
|
|
}catch(e){
|
|
return sqlite3.vtab.exceptionToRc(e, sqlite3.capi.SQLITE_XYZ);
|
|
// where SQLITE_XYZ is some call-appropriate result code.
|
|
}
|
|
```
|
|
*/
|
|
/**vfs.exceptionToRc = vtab.exceptionToRc =
|
|
(e, defaultRc=capi.SQLITE_ERROR)=>(
|
|
(e instanceof sqlite3.WasmAllocError)
|
|
? capi.SQLITE_NOMEM
|
|
: defaultRc
|
|
);*/
|
|
|
|
/**
|
|
Given an sqlite3_module method name and error object, this
|
|
function returns sqlite3.capi.SQLITE_NOMEM if (e instanceof
|
|
sqlite3.WasmAllocError), else it returns its second argument. Its
|
|
intended usage is in the methods of a sqlite3_vfs or
|
|
sqlite3_module:
|
|
|
|
```
|
|
try{
|
|
let rc = ...
|
|
return rc;
|
|
}catch(e){
|
|
return sqlite3.vtab.xError(
|
|
'xColumn', e, sqlite3.capi.SQLITE_XYZ);
|
|
// where SQLITE_XYZ is some call-appropriate result code.
|
|
}
|
|
```
|
|
|
|
If no 3rd argument is provided, its default depends on
|
|
the error type:
|
|
|
|
- An sqlite3.WasmAllocError always resolves to capi.SQLITE_NOMEM.
|
|
|
|
- If err is an SQLite3Error then its `resultCode` property
|
|
is used.
|
|
|
|
- If all else fails, capi.SQLITE_ERROR is used.
|
|
|
|
If xError.errorReporter is a function, it is called in
|
|
order to report the error, else the error is not reported.
|
|
If that function throws, that exception is ignored.
|
|
*/
|
|
vtab.xError = function f(methodName, err, defaultRc){
|
|
if(f.errorReporter instanceof Function){
|
|
try{f.errorReporter("sqlite3_module::"+methodName+"(): "+err.message);}
|
|
catch(e){/*ignored*/}
|
|
}
|
|
let rc;
|
|
if(err instanceof sqlite3.WasmAllocError) rc = capi.SQLITE_NOMEM;
|
|
else if(arguments.length>2) rc = defaultRc;
|
|
else if(err instanceof sqlite3.SQLite3Error) rc = err.resultCode;
|
|
return rc || capi.SQLITE_ERROR;
|
|
};
|
|
vtab.xError.errorReporter = 1 ? console.error.bind(console) : false;
|
|
|
|
/**
|
|
"The problem" with this is that it introduces an outer function with
|
|
a different arity than the passed-in method callback. That means we
|
|
cannot do argc validation on these. Additionally, some methods (namely
|
|
xConnect) may have call-specific error handling. It would be a shame to
|
|
hard-coded that per-method support in this function.
|
|
*/
|
|
/** vtab.methodCatcher = function(methodName, method, defaultErrRc=capi.SQLITE_ERROR){
|
|
return function(...args){
|
|
try { method(...args); }
|
|
}catch(e){ return vtab.xError(methodName, e, defaultRc) }
|
|
};
|
|
*/
|
|
|
|
/**
|
|
A helper for sqlite3_vtab::xRowid() and xUpdate()
|
|
implementations. It must be passed the final argument to one of
|
|
those methods (an output pointer to an int64 row ID) and the
|
|
value to store at the output pointer's address. Returns the same
|
|
as wasm.poke() and will throw if the 1st or 2nd arguments
|
|
are invalid for that function.
|
|
|
|
Example xRowid impl:
|
|
|
|
```
|
|
const xRowid = (pCursor, ppRowid64)=>{
|
|
const c = vtab.xCursor(pCursor);
|
|
vtab.xRowid(ppRowid64, c.myRowId);
|
|
return 0;
|
|
};
|
|
```
|
|
*/
|
|
vtab.xRowid = (ppRowid64, value)=>wasm.poke(ppRowid64, value, 'i64');
|
|
|
|
/**
|
|
A helper to initialize and set up an sqlite3_module object for
|
|
later installation into individual databases using
|
|
sqlite3_create_module(). Requires an object with the following
|
|
properties:
|
|
|
|
- `methods`: an object containing a mapping of properties with
|
|
the C-side names of the sqlite3_module methods, e.g. xCreate,
|
|
xBestIndex, etc., to JS implementations for those functions.
|
|
Certain special-case handling is performed, as described below.
|
|
|
|
- `catchExceptions` (default=false): if truthy, the given methods
|
|
are not mapped as-is, but are instead wrapped inside wrappers
|
|
which translate exceptions into result codes of SQLITE_ERROR or
|
|
SQLITE_NOMEM, depending on whether the exception is an
|
|
sqlite3.WasmAllocError. In the case of the xConnect and xCreate
|
|
methods, the exception handler also sets the output error
|
|
string to the exception's error string.
|
|
|
|
- OPTIONAL `struct`: a sqlite3.capi.sqlite3_module() instance. If
|
|
not set, one will be created automatically. If the current
|
|
"this" is-a sqlite3_module then it is unconditionally used in
|
|
place of `struct`.
|
|
|
|
- OPTIONAL `iVersion`: if set, it must be an integer value and it
|
|
gets assigned to the `$iVersion` member of the struct object.
|
|
If it's _not_ set, and the passed-in `struct` object's `$iVersion`
|
|
is 0 (the default) then this function attempts to define a value
|
|
for that property based on the list of methods it has.
|
|
|
|
If `catchExceptions` is false, it is up to the client to ensure
|
|
that no exceptions escape the methods, as doing so would move
|
|
them through the C API, leading to undefined
|
|
behavior. (vtab.xError() is intended to assist in reporting
|
|
such exceptions.)
|
|
|
|
Certain methods may refer to the same implementation. To simplify
|
|
the definition of such methods:
|
|
|
|
- If `methods.xConnect` is `true` then the value of
|
|
`methods.xCreate` is used in its place, and vice versa. sqlite
|
|
treats xConnect/xCreate functions specially if they are exactly
|
|
the same function (same pointer value).
|
|
|
|
- If `methods.xDisconnect` is true then the value of
|
|
`methods.xDestroy` is used in its place, and vice versa.
|
|
|
|
This is to facilitate creation of those methods inline in the
|
|
passed-in object without requiring the client to explicitly get a
|
|
reference to one of them in order to assign it to the other
|
|
one.
|
|
|
|
The `catchExceptions`-installed handlers will account for
|
|
identical references to the above functions and will install the
|
|
same wrapper function for both.
|
|
|
|
The given methods are expected to return integer values, as
|
|
expected by the C API. If `catchExceptions` is truthy, the return
|
|
value of the wrapped function will be used as-is and will be
|
|
translated to 0 if the function returns a falsy value (e.g. if it
|
|
does not have an explicit return). If `catchExceptions` is _not_
|
|
active, the method implementations must explicitly return integer
|
|
values.
|
|
|
|
Throws on error. On success, returns the sqlite3_module object
|
|
(`this` or `opt.struct` or a new sqlite3_module instance,
|
|
depending on how it's called).
|
|
*/
|
|
vtab.setupModule = function(opt){
|
|
let createdMod = false;
|
|
const mod = (this instanceof capi.sqlite3_module)
|
|
? this : (opt.struct || (createdMod = new capi.sqlite3_module()));
|
|
try{
|
|
const methods = opt.methods || toss("Missing 'methods' object.");
|
|
for(const e of Object.entries({
|
|
// -----^ ==> [k,v] triggers a broken code transformation in
|
|
// some versions of the emsdk toolchain.
|
|
xConnect: 'xCreate', xDisconnect: 'xDestroy'
|
|
})){
|
|
// Remap X=true to X=Y for certain X/Y combinations
|
|
const k = e[0], v = e[1];
|
|
if(true === methods[k]) methods[k] = methods[v];
|
|
else if(true === methods[v]) methods[v] = methods[k];
|
|
}
|
|
if(opt.catchExceptions){
|
|
const fwrap = function(methodName, func){
|
|
if(['xConnect','xCreate'].indexOf(methodName) >= 0){
|
|
return function(pDb, pAux, argc, argv, ppVtab, pzErr){
|
|
try{return func(...arguments) || 0}
|
|
catch(e){
|
|
if(!(e instanceof sqlite3.WasmAllocError)){
|
|
wasm.dealloc(wasm.peekPtr(pzErr));
|
|
wasm.pokePtr(pzErr, wasm.allocCString(e.message));
|
|
}
|
|
return vtab.xError(methodName, e);
|
|
}
|
|
};
|
|
}else{
|
|
return function(...args){
|
|
try{return func(...args) || 0}
|
|
catch(e){
|
|
return vtab.xError(methodName, e);
|
|
}
|
|
};
|
|
}
|
|
};
|
|
const mnames = [
|
|
'xCreate', 'xConnect', 'xBestIndex', 'xDisconnect',
|
|
'xDestroy', 'xOpen', 'xClose', 'xFilter', 'xNext',
|
|
'xEof', 'xColumn', 'xRowid', 'xUpdate',
|
|
'xBegin', 'xSync', 'xCommit', 'xRollback',
|
|
'xFindFunction', 'xRename', 'xSavepoint', 'xRelease',
|
|
'xRollbackTo', 'xShadowName'
|
|
];
|
|
const remethods = Object.create(null);
|
|
for(const k of mnames){
|
|
const m = methods[k];
|
|
if(!(m instanceof Function)) continue;
|
|
else if('xConnect'===k && methods.xCreate===m){
|
|
remethods[k] = methods.xCreate;
|
|
}else if('xCreate'===k && methods.xConnect===m){
|
|
remethods[k] = methods.xConnect;
|
|
}else{
|
|
remethods[k] = fwrap(k, m);
|
|
}
|
|
}
|
|
installMethods(mod, remethods, false);
|
|
}else{
|
|
// No automatic exception handling. Trust the client
|
|
// to not throw.
|
|
installMethods(
|
|
mod, methods, !!opt.applyArgcCheck/*undocumented option*/
|
|
);
|
|
}
|
|
if(0===mod.$iVersion){
|
|
let v;
|
|
if('number'===typeof opt.iVersion) v = opt.iVersion;
|
|
else if(mod.$xShadowName) v = 3;
|
|
else if(mod.$xSavePoint || mod.$xRelease || mod.$xRollbackTo) v = 2;
|
|
else v = 1;
|
|
mod.$iVersion = v;
|
|
}
|
|
}catch(e){
|
|
if(createdMod) createdMod.dispose();
|
|
throw e;
|
|
}
|
|
return mod;
|
|
}/*setupModule()*/;
|
|
|
|
/**
|
|
Equivalent to calling vtab.setupModule() with this sqlite3_module
|
|
object as the call's `this`.
|
|
*/
|
|
capi.sqlite3_module.prototype.setupModule = function(opt){
|
|
return vtab.setupModule.call(this, opt);
|
|
};
|
|
}/*sqlite3ApiBootstrap.initializers.push()*/);
|