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-rw-r--r--vendor/git.iim.gay/grufwub/go-nowish/README.md5
-rw-r--r--vendor/git.iim.gay/grufwub/go-nowish/time.go141
-rw-r--r--vendor/git.iim.gay/grufwub/go-nowish/timeout.go111
-rw-r--r--vendor/git.iim.gay/grufwub/go-nowish/util.go10
4 files changed, 267 insertions, 0 deletions
diff --git a/vendor/git.iim.gay/grufwub/go-nowish/README.md b/vendor/git.iim.gay/grufwub/go-nowish/README.md
new file mode 100644
index 000000000..17dd75374
--- /dev/null
+++ b/vendor/git.iim.gay/grufwub/go-nowish/README.md
@@ -0,0 +1,5 @@
+nowish is a very simple library for creating Go clocks that give a good (ish)
+estimate of the "now" time, "ish" depending on the precision you request
+
+similar to fastime, but more bare bones and using unsafe pointers instead of
+atomic value since we don't need to worry about type changes \ No newline at end of file
diff --git a/vendor/git.iim.gay/grufwub/go-nowish/time.go b/vendor/git.iim.gay/grufwub/go-nowish/time.go
new file mode 100644
index 000000000..30027ac0b
--- /dev/null
+++ b/vendor/git.iim.gay/grufwub/go-nowish/time.go
@@ -0,0 +1,141 @@
+package nowish
+
+import (
+ "sync"
+ "sync/atomic"
+ "time"
+ "unsafe"
+)
+
+// Start returns a new Clock instance initialized and
+// started with the provided precision, along with the
+// stop function for it's underlying timer
+func Start(precision time.Duration) (*Clock, func()) {
+ c := Clock{}
+ return &c, c.Start(precision)
+}
+
+type Clock struct {
+ noCopy noCopy //nolint noCopy because a copy will fuck with atomics
+
+ // format stores the time formatting style string
+ format string
+
+ // valid indicates whether the current value stored in .Format is valid
+ valid uint32
+
+ // mutex protects writes to .Format, not because it would be unsafe, but
+ // because we want to minimize unnnecessary allocations
+ mutex sync.Mutex
+
+ // Format is an unsafe pointer to the last-updated time format string
+ Format unsafe.Pointer
+
+ // Time is an unsafe pointer to the last-updated time.Time object
+ Time unsafe.Pointer
+}
+
+// Start starts the clock with the provided precision, the
+// returned function is the stop function for the underlying timer
+func (c *Clock) Start(precision time.Duration) func() {
+ // Create ticker from duration
+ tick := time.NewTicker(precision)
+
+ // Set initial time
+ t := time.Now()
+ atomic.StorePointer(&c.Time, unsafe.Pointer(&t))
+
+ // Set initial format
+ s := ""
+ atomic.StorePointer(&c.Format, unsafe.Pointer(&s))
+
+ // If formatting string unset, set default
+ c.mutex.Lock()
+ if c.format == "" {
+ c.format = time.RFC822
+ }
+ c.mutex.Unlock()
+
+ // Start main routine
+ go c.run(tick)
+
+ // Return stop fn
+ return tick.Stop
+}
+
+// run is the internal clock ticking loop
+func (c *Clock) run(tick *time.Ticker) {
+ for {
+ // Wait on tick
+ _, ok := <-tick.C
+
+ // Channel closed
+ if !ok {
+ break
+ }
+
+ // Update time
+ t := time.Now()
+ atomic.StorePointer(&c.Time, unsafe.Pointer(&t))
+
+ // Invalidate format string
+ atomic.StoreUint32(&c.valid, 0)
+ }
+}
+
+// Now returns a good (ish) estimate of the current 'now' time
+func (c *Clock) Now() time.Time {
+ return *(*time.Time)(atomic.LoadPointer(&c.Time))
+}
+
+// NowFormat returns the formatted "now" time, cached until next tick and "now" updates
+func (c *Clock) NowFormat() string {
+ // If format still valid, return this
+ if atomic.LoadUint32(&c.valid) == 1 {
+ return *(*string)(atomic.LoadPointer(&c.Format))
+ }
+
+ // Get mutex lock
+ c.mutex.Lock()
+
+ // Double check still invalid
+ if atomic.LoadUint32(&c.valid) == 1 {
+ c.mutex.Unlock()
+ return *(*string)(atomic.LoadPointer(&c.Format))
+ }
+
+ // Calculate time format
+ b := c.Now().AppendFormat(
+ make([]byte, 0, len(c.format)),
+ c.format,
+ )
+
+ // Update the stored value and set valid!
+ atomic.StorePointer(&c.Format, unsafe.Pointer(&b))
+ atomic.StoreUint32(&c.valid, 1)
+
+ // Unlock and return
+ c.mutex.Unlock()
+
+ // Note:
+ // it's safe to do this conversion here
+ // because this byte slice will never change.
+ // and we have the direct pointer to it, we're
+ // not requesting it atomicly via c.Format
+ return *(*string)(unsafe.Pointer(&b))
+}
+
+// SetFormat sets the time format string used by .NowFormat()
+func (c *Clock) SetFormat(format string) {
+ // Get mutex lock
+ c.mutex.Lock()
+
+ // Update time format
+ c.format = format
+
+ // Invalidate current format string
+ atomic.StoreUint32(&c.valid, 0)
+
+ // Unlock
+ c.mutex.Unlock()
+}
diff --git a/vendor/git.iim.gay/grufwub/go-nowish/timeout.go b/vendor/git.iim.gay/grufwub/go-nowish/timeout.go
new file mode 100644
index 000000000..15222281a
--- /dev/null
+++ b/vendor/git.iim.gay/grufwub/go-nowish/timeout.go
@@ -0,0 +1,111 @@
+package nowish
+
+import (
+ "errors"
+ "sync/atomic"
+ "time"
+)
+
+// ErrTimeoutStarted is returned if a Timeout interface is attempted to be reused while still in operation
+var ErrTimeoutStarted = errors.New("nowish: timeout already started")
+
+// timeoutState provides a thread-safe timeout state mechanism
+type timeoutState uint32
+
+// start attempts to start the state, must be already reset, returns success
+func (t *timeoutState) start() bool {
+ return atomic.CompareAndSwapUint32((*uint32)(t), 0, 1)
+}
+
+// stop attempts to stop the state, must already be started, returns success
+func (t *timeoutState) stop() bool {
+ return atomic.CompareAndSwapUint32((*uint32)(t), 1, 2)
+}
+
+// reset is fairly self explanatory
+func (t *timeoutState) reset() {
+ atomic.StoreUint32((*uint32)(t), 0)
+}
+
+// Timeout provides a reusable structure for enforcing timeouts with a cancel
+type Timeout interface {
+ // Start starts the timer with supplied timeout. If timeout is reached before
+ // cancel then supplied timeout hook will be called. Error may be called if
+ // Timeout is already running when this function is called
+ Start(time.Duration, func()) error
+
+ // Cancel cancels the currently running timer. If a cancel is achieved, then
+ // this function will return after the timeout goroutine is finished
+ Cancel()
+}
+
+// NewTimeout returns a new Timeout instance
+func NewTimeout() Timeout {
+ t := &timeout{
+ tk: time.NewTicker(time.Minute),
+ ch: make(chan struct{}),
+ }
+ t.tk.Stop() // don't keep it running
+ return t
+}
+
+// timeout is the Timeout implementation that we force
+// initialization on via NewTimeout by unexporting it
+type timeout struct {
+ noCopy noCopy //nolint noCopy because a copy will mess with atomics
+
+ tk *time.Ticker // tk is the underlying timeout-timer
+ ch chan struct{} // ch is the cancel propagation channel
+ st timeoutState // st stores the current timeout state (and protects concurrent use)
+}
+
+func (t *timeout) Start(d time.Duration, hook func()) error {
+ // Attempt to acquire start
+ if !t.st.start() {
+ return ErrTimeoutStarted
+ }
+
+ // Start the ticker
+ t.tk.Reset(d)
+
+ go func() {
+ cancelled := false
+
+ select {
+ // Timeout reached
+ case <-t.tk.C:
+ if !t.st.stop() {
+ // cancel was called in the nick of time
+ <-t.ch
+ cancelled = true
+ }
+
+ // Cancel called
+ case <-t.ch:
+ cancelled = true
+ }
+
+ // Stop ticker
+ t.tk.Stop()
+
+ // If timed out call hook
+ if !cancelled {
+ hook()
+ }
+
+ // Finally, reset state
+ t.st.reset()
+ }()
+
+ return nil
+}
+
+func (t *timeout) Cancel() {
+ // Attempt to acquire stop
+ if !t.st.stop() {
+ return
+ }
+
+ // Send a cancel signal
+ t.ch <- struct{}{}
+}
diff --git a/vendor/git.iim.gay/grufwub/go-nowish/util.go b/vendor/git.iim.gay/grufwub/go-nowish/util.go
new file mode 100644
index 000000000..31fe9050e
--- /dev/null
+++ b/vendor/git.iim.gay/grufwub/go-nowish/util.go
@@ -0,0 +1,10 @@
+package nowish
+
+//nolint
+type noCopy struct{}
+
+//nolint
+func (*noCopy) Lock() {}
+
+//nolint
+func (*noCopy) Unlock() {}