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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
extern crate atomic_refcell;
extern crate crossbeam_utils;
#[macro_use]
extern crate cstr;
extern crate libc;
extern crate log;
extern crate moz_task;
extern crate nserror;
extern crate nsstring;
extern crate rkv;
extern crate storage_variant;
extern crate tempfile;
extern crate thin_vec;
extern crate thiserror;
extern crate xpcom;
mod error;
mod owned_value;
mod task;
use atomic_refcell::AtomicRefCell;
use error::KeyValueError;
use libc::c_void;
use moz_task::{create_background_task_queue, DispatchOptions, TaskRunnable};
use nserror::{nsresult, NS_ERROR_FAILURE, NS_OK};
use nsstring::{nsACString, nsCString};
use owned_value::{owned_to_variant, variant_to_owned};
use rkv::backend::{RecoveryStrategy, SafeModeDatabase, SafeModeEnvironment};
use rkv::OwnedValue;
use std::{
ptr,
sync::{Arc, RwLock},
vec::IntoIter,
};
use task::{
ClearTask, DeleteTask, EnumerateTask, GetOrCreateWithOptionsTask, GetTask, HasTask, PutTask,
WriteManyTask,
};
use thin_vec::ThinVec;
use xpcom::{
getter_addrefs,
interfaces::{
nsIKeyValueDatabaseCallback, nsIKeyValueEnumeratorCallback, nsIKeyValuePair,
nsIKeyValueService, nsIKeyValueVariantCallback, nsIKeyValueVoidCallback,
nsISerialEventTarget, nsIVariant,
},
nsIID, xpcom, xpcom_method, RefPtr,
};
type Rkv = rkv::Rkv<SafeModeEnvironment>;
type SingleStore = rkv::SingleStore<SafeModeDatabase>;
type KeyValuePairResult = Result<(String, OwnedValue), KeyValueError>;
#[no_mangle]
pub unsafe extern "C" fn nsKeyValueServiceConstructor(
iid: &nsIID,
result: *mut *mut c_void,
) -> nsresult {
*result = ptr::null_mut();
let service = KeyValueService::new();
service.QueryInterface(iid, result)
}
// For each public XPCOM method in the nsIKeyValue* interfaces, we implement
// a pair of Rust methods:
//
// 1. a method named after the XPCOM (as modified by the XPIDL parser, i.e.
// by capitalization of its initial letter) that returns an nsresult;
//
// 2. a method with a Rust-y name that returns a Result<(), KeyValueError>.
//
// XPCOM calls the first method, which is only responsible for calling
// the second one and converting its Result to an nsresult (logging errors
// in the process). The second method is responsible for doing the work.
//
// For example, given an XPCOM method FooBar, we implement a method FooBar
// that calls a method foo_bar. foo_bar returns a Result<(), KeyValueError>,
// and FooBar converts that to an nsresult.
//
// This design allows us to use Rust idioms like the question mark operator
// to simplify the implementation in the second method while returning XPCOM-
// compatible nsresult values to XPCOM callers.
//
// The XPCOM methods are implemented using the xpcom_method! declarative macro
// from the xpcom crate.
#[xpcom(implement(nsIKeyValueService), atomic)]
pub struct KeyValueService {}
impl KeyValueService {
fn new() -> RefPtr<KeyValueService> {
KeyValueService::allocate(InitKeyValueService {})
}
xpcom_method!(
get_or_create => GetOrCreate(
callback: *const nsIKeyValueDatabaseCallback,
path: *const nsACString,
name: *const nsACString
)
);
fn get_or_create(
&self,
callback: &nsIKeyValueDatabaseCallback,
path: &nsACString,
name: &nsACString,
) -> Result<(), nsresult> {
let task = Box::new(GetOrCreateWithOptionsTask::new(
RefPtr::new(callback),
nsCString::from(path),
nsCString::from(name),
RecoveryStrategy::Error,
));
TaskRunnable::new("KVService::GetOrCreate", task)?
.dispatch_background_task_with_options(DispatchOptions::default().may_block(true))
}
xpcom_method!(
get_or_create_with_options => GetOrCreateWithOptions(
callback: *const nsIKeyValueDatabaseCallback,
path: *const nsACString,
name: *const nsACString,
strategy: u8
)
);
fn get_or_create_with_options(
&self,
callback: &nsIKeyValueDatabaseCallback,
path: &nsACString,
name: &nsACString,
xpidl_strategy: u8,
) -> Result<(), nsresult> {
let strategy = match xpidl_strategy {
nsIKeyValueService::ERROR => RecoveryStrategy::Error,
nsIKeyValueService::DISCARD => RecoveryStrategy::Discard,
nsIKeyValueService::RENAME => RecoveryStrategy::Rename,
_ => return Err(NS_ERROR_FAILURE),
};
let task = Box::new(GetOrCreateWithOptionsTask::new(
RefPtr::new(callback),
nsCString::from(path),
nsCString::from(name),
strategy,
));
TaskRunnable::new("KVService::GetOrCreateWithOptions", task)?
.dispatch_background_task_with_options(DispatchOptions::default().may_block(true))
}
}
#[xpcom(implement(nsIKeyValueDatabase), atomic)]
pub struct KeyValueDatabase {
rkv: Arc<RwLock<Rkv>>,
store: SingleStore,
queue: RefPtr<nsISerialEventTarget>,
}
impl KeyValueDatabase {
fn new(
rkv: Arc<RwLock<Rkv>>,
store: SingleStore,
) -> Result<RefPtr<KeyValueDatabase>, KeyValueError> {
let queue = create_background_task_queue(cstr!("KeyValueDatabase"))?;
Ok(KeyValueDatabase::allocate(InitKeyValueDatabase {
rkv,
store,
queue,
}))
}
xpcom_method!(
put => Put(
callback: *const nsIKeyValueVoidCallback,
key: *const nsACString,
value: *const nsIVariant
)
);
fn put(
&self,
callback: &nsIKeyValueVoidCallback,
key: &nsACString,
value: &nsIVariant,
) -> Result<(), nsresult> {
let value = variant_to_owned(value)?.ok_or(KeyValueError::UnexpectedValue)?;
let task = Box::new(PutTask::new(
RefPtr::new(callback),
Arc::clone(&self.rkv),
self.store,
nsCString::from(key),
value,
));
TaskRunnable::dispatch(TaskRunnable::new("KVDatabase::Put", task)?, &self.queue)
}
xpcom_method!(
write_many => WriteMany(
callback: *const nsIKeyValueVoidCallback,
pairs: *const ThinVec<Option<RefPtr<nsIKeyValuePair>>>
)
);
fn write_many(
&self,
callback: &nsIKeyValueVoidCallback,
pairs: &ThinVec<Option<RefPtr<nsIKeyValuePair>>>,
) -> Result<(), nsresult> {
let mut entries = Vec::with_capacity(pairs.len());
for pair in pairs {
let pair = pair
.as_ref()
.ok_or(nsresult::from(KeyValueError::UnexpectedValue))?;
let mut key = nsCString::new();
unsafe { pair.GetKey(&mut *key) }.to_result()?;
if key.is_empty() {
return Err(nsresult::from(KeyValueError::UnexpectedValue));
}
let val: RefPtr<nsIVariant> = getter_addrefs(|p| unsafe { pair.GetValue(p) })?;
let value = variant_to_owned(&val)?;
entries.push((key, value));
}
let task = Box::new(WriteManyTask::new(
RefPtr::new(callback),
Arc::clone(&self.rkv),
self.store,
entries,
));
TaskRunnable::dispatch(
TaskRunnable::new("KVDatabase::WriteMany", task)?,
&self.queue,
)
}
xpcom_method!(
get => Get(
callback: *const nsIKeyValueVariantCallback,
key: *const nsACString,
default_value: *const nsIVariant
)
);
fn get(
&self,
callback: &nsIKeyValueVariantCallback,
key: &nsACString,
default_value: &nsIVariant,
) -> Result<(), nsresult> {
let task = Box::new(GetTask::new(
RefPtr::new(callback),
Arc::clone(&self.rkv),
self.store,
nsCString::from(key),
variant_to_owned(default_value)?,
));
TaskRunnable::dispatch(TaskRunnable::new("KVDatabase::Get", task)?, &self.queue)
}
xpcom_method!(
has => Has(callback: *const nsIKeyValueVariantCallback, key: *const nsACString)
);
fn has(&self, callback: &nsIKeyValueVariantCallback, key: &nsACString) -> Result<(), nsresult> {
let task = Box::new(HasTask::new(
RefPtr::new(callback),
Arc::clone(&self.rkv),
self.store,
nsCString::from(key),
));
TaskRunnable::dispatch(TaskRunnable::new("KVDatabase::Has", task)?, &self.queue)
}
xpcom_method!(
delete => Delete(callback: *const nsIKeyValueVoidCallback, key: *const nsACString)
);
fn delete(&self, callback: &nsIKeyValueVoidCallback, key: &nsACString) -> Result<(), nsresult> {
let task = Box::new(DeleteTask::new(
RefPtr::new(callback),
Arc::clone(&self.rkv),
self.store,
nsCString::from(key),
));
TaskRunnable::dispatch(TaskRunnable::new("KVDatabase::Delete", task)?, &self.queue)
}
xpcom_method!(
clear => Clear(callback: *const nsIKeyValueVoidCallback)
);
fn clear(&self, callback: &nsIKeyValueVoidCallback) -> Result<(), nsresult> {
let task = Box::new(ClearTask::new(
RefPtr::new(callback),
Arc::clone(&self.rkv),
self.store,
));
TaskRunnable::dispatch(TaskRunnable::new("KVDatabase::Clear", task)?, &self.queue)
}
xpcom_method!(
enumerate => Enumerate(
callback: *const nsIKeyValueEnumeratorCallback,
from_key: *const nsACString,
to_key: *const nsACString
)
);
fn enumerate(
&self,
callback: &nsIKeyValueEnumeratorCallback,
from_key: &nsACString,
to_key: &nsACString,
) -> Result<(), nsresult> {
let task = Box::new(EnumerateTask::new(
RefPtr::new(callback),
Arc::clone(&self.rkv),
self.store,
nsCString::from(from_key),
nsCString::from(to_key),
));
TaskRunnable::dispatch(
TaskRunnable::new("KVDatabase::Enumerate", task)?,
&self.queue,
)
}
}
#[xpcom(implement(nsIKeyValueEnumerator), atomic)]
pub struct KeyValueEnumerator {
iter: AtomicRefCell<IntoIter<KeyValuePairResult>>,
}
impl KeyValueEnumerator {
fn new(pairs: Vec<KeyValuePairResult>) -> RefPtr<KeyValueEnumerator> {
KeyValueEnumerator::allocate(InitKeyValueEnumerator {
iter: AtomicRefCell::new(pairs.into_iter()),
})
}
xpcom_method!(has_more_elements => HasMoreElements() -> bool);
fn has_more_elements(&self) -> Result<bool, KeyValueError> {
Ok(!self.iter.borrow().as_slice().is_empty())
}
xpcom_method!(get_next => GetNext() -> *const nsIKeyValuePair);
fn get_next(&self) -> Result<RefPtr<nsIKeyValuePair>, KeyValueError> {
let mut iter = self.iter.borrow_mut();
let (key, value) = iter
.next()
.ok_or_else(|| KeyValueError::from(NS_ERROR_FAILURE))??;
// We fail on retrieval of the key/value pair if the key isn't valid
// UTF-*, if the value is unexpected, or if we encountered a store error
// while retrieving the pair.
Ok(RefPtr::new(
KeyValuePair::new(key, value).coerce::<nsIKeyValuePair>(),
))
}
}
#[xpcom(implement(nsIKeyValuePair), atomic)]
pub struct KeyValuePair {
key: String,
value: OwnedValue,
}
impl KeyValuePair {
fn new(key: String, value: OwnedValue) -> RefPtr<KeyValuePair> {
KeyValuePair::allocate(InitKeyValuePair { key, value })
}
xpcom_method!(get_key => GetKey() -> nsACString);
xpcom_method!(get_value => GetValue() -> *const nsIVariant);
fn get_key(&self) -> Result<nsCString, KeyValueError> {
Ok(nsCString::from(&self.key))
}
fn get_value(&self) -> Result<RefPtr<nsIVariant>, KeyValueError> {
Ok(owned_to_variant(self.value.clone())?)
}
}