Function adjustRead

packages/effect/src/internal/stm/tReentrantLock.ts:156–181

(self: TReentrantLock.TReentrantLock, delta: number)

}

const adjustRead = (self: TReentrantLock.TReentrantLock, delta: number): STM.STM<number> =>
  core.withSTMRuntime((runtime) => {
    const lock = tRef.unsafeGet(self.state, runtime.journal)
    if (isReadLock(lock)) {
      const result = adjustReadLock(lock, runtime.fiberId, delta)
      tRef.unsafeSet(self.state, result, runtime.journal)
      return core.succeed(result.readLocksHeld(runtime.fiberId))
    }
    if (isWriteLock(lock) && Equal.equals(runtime.fiberId)(lock.fiberId)) {
      const newTotal = lock.readLocks + delta
      if (newTotal < 0) {
        throw new Error(
          `Defect: Fiber ${
            FiberId.threadName(runtime.fiberId)
          } releasing read locks it does not hold, newTotal: ${newTotal}`
        )
      }
      tRef.unsafeSet(
        self.state,
        new WriteLock(newTotal, lock.writeLocks, runtime.fiberId),
        runtime.journal
      )
      return core.succeed(newTotal)
    }
    return core.retry
  })

/** @internal */
export const acquireRead = (self: TReentrantLock.TReentrantLock): STM.STM<number> => adjustRead(self, 1)