imag/libimagstorestdhook/src/flock.rs

148 lines
3.7 KiB
Rust

use toml::Value;
use fs2::FileExt;
use std::fs::File;
use libimagstore::hook::Hook;
use libimagstore::hook::accessor::HookDataAccessor as HDA;
use libimagstore::hook::accessor::HookDataAccessorProvider;
use libimagstore::hook::accessor::StoreIdAccessor;
use libimagstore::hook::accessor::MutableHookDataAccessor;
use libimagstore::hook::accessor::NonMutableHookDataAccessor;
use libimagstore::hook::result::HookResult;
use libimagstore::hook::error::{HookError, HookErrorKind};
use libimagstore::storeid::StoreId;
use libimagstore::store::FileLockEntry;
use libimagstore::store::Entry;
mod error {
generate_error_imports!();
generate_error_types!(FlockError, FlockErrorKind,
IOError => "IO Error",
StoreIdPathBufConvertError => "Error while converting StoreId to PathBuf",
FileOpenError => "Error on File::open()",
LockError => "Error while lock()ing",
UnlockError => "Error while unlock()ing"
);
}
use self::error::FlockError as FE;
use self::error::FlockErrorKind as FEK;
use self::error::MapErrInto;
trait EntryFlock {
fn lock(&self) -> Result<(), FE>;
fn unlock(&self) -> Result<(), FE>;
}
fn open_file(id: StoreId) -> Result<File, FE> {
id.into_pathbuf()
.map_err_into(FEK::StoreIdPathBufConvertError)
.and_then(|loc| {
File::open(loc)
.map_err_into(FEK::FileOpenError)
.map_err_into(FEK::IOError)
})
}
impl EntryFlock for Entry {
fn lock(&self) -> Result<(), FE> {
open_file(self.get_location().clone())
.and_then(|file| {
file.lock_exclusive()
.map_err_into(FEK::LockError)
.map_err_into(FEK::IOError)
})
}
fn unlock(&self) -> Result<(), FE> {
open_file(self.get_location().clone())
.and_then(|file| {
file.unlock()
.map_err_into(FEK::UnlockError)
.map_err_into(FEK::LockError)
.map_err_into(FEK::IOError)
})
}
}
#[derive(PartialEq, Eq, Debug, Clone)]
pub enum Action {
Lock,
Unlock
}
fn action_to_str(a: &Action) -> &'static str {
match *a {
Action::Lock => "lock",
Action::Unlock => "unlock",
}
}
#[derive(Debug, Clone)]
pub struct FlockUpdateHook {
action: Action,
}
impl FlockUpdateHook {
pub fn new(action: Action) -> FlockUpdateHook {
FlockUpdateHook {
action: action,
}
}
}
impl Hook for FlockUpdateHook {
fn name(&self) -> &'static str {
"stdhook_flock_update"
}
fn set_config(&mut self, _: &Value) {
() // We are not configurable here.
}
}
impl HookDataAccessorProvider for FlockUpdateHook {
fn accessor(&self) -> HDA {
HDA::StoreIdAccess(self)
}
}
impl StoreIdAccessor for FlockUpdateHook {
fn access(&self, id: &StoreId) -> HookResult<()> {
debug!("[FLOCK HOOK][{}] {:?}", action_to_str(&self.action), id);
Ok(())
}
}
impl MutableHookDataAccessor for FlockUpdateHook {
fn access_mut(&self, fle: &mut FileLockEntry) -> HookResult<()> {
debug!("[FLOCK HOOK][{}] {:?}", action_to_str(&self.action), fle.get_location());
fle.lock()
.map_err(|e| HookError::new(HookErrorKind::HookExecutionError, Some(Box::new(e))))
.map(|_| ())
}
}
impl NonMutableHookDataAccessor for FlockUpdateHook {
fn access(&self, fle: &FileLockEntry) -> HookResult<()> {
debug!("[FLOCK HOOK][{}] {:?}", action_to_str(&self.action), fle.get_location());
fle.unlock()
.map_err(|e| HookError::new(HookErrorKind::HookExecutionError, Some(Box::new(e))))
.map(|_| ())
}
}