mirror of https://github.com/periph/devices
updates and testing of implementations
imle
5 years ago
parent
050bc7a20a
commit
7b71c747f2
@ -1,216 +0,0 @@
|
|||||||
package firmatareg
|
|
||||||
|
|
||||||
import (
|
|
||||||
"errors"
|
|
||||||
"strconv"
|
|
||||||
"strings"
|
|
||||||
"sync"
|
|
||||||
|
|
||||||
"periph.io/x/devices/v3/firmata"
|
|
||||||
)
|
|
||||||
|
|
||||||
// Opener opens a handle to a firmata device.
|
|
||||||
//
|
|
||||||
// It is provided by the actual device driver.
|
|
||||||
type Opener func() (firmata.ClientI, error)
|
|
||||||
|
|
||||||
// Ref references a Firmata device.
|
|
||||||
//
|
|
||||||
// It is returned by All() to enumerate all registered devices.
|
|
||||||
type Ref struct {
|
|
||||||
// Name of the device.
|
|
||||||
//
|
|
||||||
// It must be unique across the host.
|
|
||||||
Name string
|
|
||||||
// Aliases are the alternative names that can be used to reference this bus.
|
|
||||||
Aliases []string
|
|
||||||
// Open is the factory to open a handle to this Firmata device.
|
|
||||||
Open Opener
|
|
||||||
}
|
|
||||||
|
|
||||||
// Open opens a firmata device by its name, an alias or its file path and returns
|
|
||||||
// a handle to it.
|
|
||||||
//
|
|
||||||
// Specify the empty string "" to get the first available device. This is the
|
|
||||||
// recommended default value unless an application knows the exact device to use.
|
|
||||||
//
|
|
||||||
// Each device can register multiple aliases, each leading to the same device handle.
|
|
||||||
//
|
|
||||||
// "file path" is a generic concept that is highly dependent on the platform
|
|
||||||
// and OS. Depending on the OS, a serial port can be `/dev/tty*` or `COM*`.
|
|
||||||
func Open(name string) (firmata.ClientI, error) {
|
|
||||||
var r *Ref
|
|
||||||
var err error
|
|
||||||
func() {
|
|
||||||
mu.Lock()
|
|
||||||
defer mu.Unlock()
|
|
||||||
if len(byName) == 0 {
|
|
||||||
err = errors.New("firmatareg: no device found; did you forget to call Init()")
|
|
||||||
return
|
|
||||||
}
|
|
||||||
if len(name) == 0 {
|
|
||||||
r = getDefault()
|
|
||||||
return
|
|
||||||
}
|
|
||||||
// Try by name, by alias, by number.
|
|
||||||
if r = byName[name]; r == nil {
|
|
||||||
r = byAlias[name]
|
|
||||||
}
|
|
||||||
}()
|
|
||||||
if err != nil {
|
|
||||||
return nil, err
|
|
||||||
}
|
|
||||||
if r == nil {
|
|
||||||
return nil, errors.New("firmatareg: can't open unknown device: " + strconv.Quote(name))
|
|
||||||
}
|
|
||||||
return r.Open()
|
|
||||||
}
|
|
||||||
|
|
||||||
// All returns a copy of all the registered references to all know firmata devices
|
|
||||||
// available on this host.
|
|
||||||
//
|
|
||||||
// The list is sorted by the bus name.
|
|
||||||
func All() []*Ref {
|
|
||||||
mu.Lock()
|
|
||||||
defer mu.Unlock()
|
|
||||||
out := make([]*Ref, 0, len(byName))
|
|
||||||
for _, v := range byName {
|
|
||||||
r := &Ref{Name: v.Name, Aliases: make([]string, len(v.Aliases)), Open: v.Open}
|
|
||||||
copy(r.Aliases, v.Aliases)
|
|
||||||
out = insertRef(out, r)
|
|
||||||
}
|
|
||||||
return out
|
|
||||||
}
|
|
||||||
|
|
||||||
// Register registers a firmata device.
|
|
||||||
//
|
|
||||||
// Registering the same device name twice is an error, e.g. o.Name().
|
|
||||||
func Register(name string, aliases []string, o Opener) error {
|
|
||||||
if len(name) == 0 {
|
|
||||||
return errors.New("firmatareg: can't register a bus with no name")
|
|
||||||
}
|
|
||||||
if o == nil {
|
|
||||||
return errors.New("firmatareg: can't register bus " + strconv.Quote(name) + " with nil Opener")
|
|
||||||
}
|
|
||||||
if _, err := strconv.Atoi(name); err == nil {
|
|
||||||
return errors.New("firmatareg: can't register bus " + strconv.Quote(name) + " with name being only a number")
|
|
||||||
}
|
|
||||||
if strings.Contains(name, ":") {
|
|
||||||
return errors.New("firmatareg: can't register bus " + strconv.Quote(name) + " with name containing ':'")
|
|
||||||
}
|
|
||||||
for _, alias := range aliases {
|
|
||||||
if len(alias) == 0 {
|
|
||||||
return errors.New("firmatareg: can't register bus " + strconv.Quote(name) + " with an empty alias")
|
|
||||||
}
|
|
||||||
if name == alias {
|
|
||||||
return errors.New("firmatareg: can't register bus " + strconv.Quote(name) + " with an alias the same as the bus name")
|
|
||||||
}
|
|
||||||
if _, err := strconv.Atoi(alias); err == nil {
|
|
||||||
return errors.New("firmatareg: can't register bus " + strconv.Quote(name) + " with an alias that is a number: " + strconv.Quote(alias))
|
|
||||||
}
|
|
||||||
if strings.Contains(alias, ":") {
|
|
||||||
return errors.New("firmatareg: can't register bus " + strconv.Quote(name) + " with an alias containing ':': " + strconv.Quote(alias))
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
mu.Lock()
|
|
||||||
defer mu.Unlock()
|
|
||||||
if _, ok := byName[name]; ok {
|
|
||||||
return errors.New("firmatareg: can't register bus " + strconv.Quote(name) + " twice")
|
|
||||||
}
|
|
||||||
if _, ok := byAlias[name]; ok {
|
|
||||||
return errors.New("firmatareg: can't register bus " + strconv.Quote(name) + " twice; it is already an alias")
|
|
||||||
}
|
|
||||||
for _, alias := range aliases {
|
|
||||||
if _, ok := byName[alias]; ok {
|
|
||||||
return errors.New("firmatareg: can't register bus " + strconv.Quote(name) + " twice; alias " + strconv.Quote(alias) + " is already a bus")
|
|
||||||
}
|
|
||||||
if _, ok := byAlias[alias]; ok {
|
|
||||||
return errors.New("firmatareg: can't register bus " + strconv.Quote(name) + " twice; alias " + strconv.Quote(alias) + " is already an alias")
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
r := &Ref{Name: name, Aliases: make([]string, len(aliases)), Open: o}
|
|
||||||
copy(r.Aliases, aliases)
|
|
||||||
byName[name] = r
|
|
||||||
for _, alias := range aliases {
|
|
||||||
byAlias[alias] = r
|
|
||||||
}
|
|
||||||
return nil
|
|
||||||
}
|
|
||||||
|
|
||||||
// Unregister removes a previously registered firmata device.
|
|
||||||
//
|
|
||||||
// This can happen when a firmata device is exposed via a USB device and the device
|
|
||||||
// is unplugged.
|
|
||||||
func Unregister(name string) error {
|
|
||||||
mu.Lock()
|
|
||||||
defer mu.Unlock()
|
|
||||||
r := byName[name]
|
|
||||||
if r == nil {
|
|
||||||
return errors.New("firmatareg: can't unregister unknown bus name " + strconv.Quote(name))
|
|
||||||
}
|
|
||||||
delete(byName, name)
|
|
||||||
for _, alias := range r.Aliases {
|
|
||||||
delete(byAlias, alias)
|
|
||||||
}
|
|
||||||
return nil
|
|
||||||
}
|
|
||||||
|
|
||||||
//
|
|
||||||
|
|
||||||
var (
|
|
||||||
mu sync.Mutex
|
|
||||||
byName = map[string]*Ref{}
|
|
||||||
// Caches
|
|
||||||
byNumber = map[int]*Ref{}
|
|
||||||
byAlias = map[string]*Ref{}
|
|
||||||
)
|
|
||||||
|
|
||||||
// getDefault returns the Ref that should be used as the default bus.
|
|
||||||
func getDefault() *Ref {
|
|
||||||
var o *Ref
|
|
||||||
if len(byNumber) == 0 {
|
|
||||||
// Fallback to use byName using a lexical sort.
|
|
||||||
name := ""
|
|
||||||
for n, o2 := range byName {
|
|
||||||
if len(name) == 0 || n < name {
|
|
||||||
o = o2
|
|
||||||
name = n
|
|
||||||
}
|
|
||||||
}
|
|
||||||
return o
|
|
||||||
}
|
|
||||||
number := int((^uint(0)) >> 1)
|
|
||||||
for n, o2 := range byNumber {
|
|
||||||
if number > n {
|
|
||||||
number = n
|
|
||||||
o = o2
|
|
||||||
}
|
|
||||||
}
|
|
||||||
return o
|
|
||||||
}
|
|
||||||
|
|
||||||
func insertRef(l []*Ref, r *Ref) []*Ref {
|
|
||||||
n := r.Name
|
|
||||||
i := search(len(l), func(i int) bool { return l[i].Name > n })
|
|
||||||
l = append(l, nil)
|
|
||||||
copy(l[i+1:], l[i:])
|
|
||||||
l[i] = r
|
|
||||||
return l
|
|
||||||
}
|
|
||||||
|
|
||||||
// search implements the same algorithm as sort.Search().
|
|
||||||
//
|
|
||||||
// It was extracted to not depend on sort, which depends on reflect.
|
|
||||||
func search(n int, f func(int) bool) int {
|
|
||||||
lo := 0
|
|
||||||
for hi := n; lo < hi; {
|
|
||||||
if i := int(uint(lo+hi) >> 1); !f(i) {
|
|
||||||
lo = i + 1
|
|
||||||
} else {
|
|
||||||
hi = i
|
|
||||||
}
|
|
||||||
}
|
|
||||||
return lo
|
|
||||||
}
|
|
||||||
Loading…
Reference in New Issue