diff options
Diffstat (limited to 'vendor/github.com/karalabe/hid/hid_enabled.go')
| -rw-r--r-- | vendor/github.com/karalabe/hid/hid_enabled.go | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/vendor/github.com/karalabe/hid/hid_enabled.go b/vendor/github.com/karalabe/hid/hid_enabled.go index 3ceecce0d..419273be6 100644 --- a/vendor/github.com/karalabe/hid/hid_enabled.go +++ b/vendor/github.com/karalabe/hid/hid_enabled.go @@ -2,7 +2,7 @@ // Copyright (c) 2017 Péter Szilágyi. All rights reserved. // // This file is released under the 3-clause BSD license. Note however that Linux -// support depends on libusb, released under GNU GPL 2.1 or later. +// support depends on libusb, released under LGNU GPL 2.1 or later. // +build linux,cgo darwin,!ios,cgo windows,cgo @@ -48,6 +48,15 @@ import ( "unsafe" ) +// enumerateLock is a mutex serializing access to USB device enumeration needed +// by the macOS USB HID system calls, which require 2 consecutive method calls +// for enumeration, causing crashes if called concurrently. +// +// For more details, see: +// https://developer.apple.com/documentation/iokit/1438371-iohidmanagersetdevicematching +// > "subsequent calls will cause the hid manager to release previously enumerated devices" +var enumerateLock sync.Mutex + func init() { // Initialize the HIDAPI library C.hid_init() @@ -66,6 +75,9 @@ func Supported() bool { // - If the product id is set to 0 then any product matches. // - If the vendor and product id are both 0, all HID devices are returned. func Enumerate(vendorID uint16, productID uint16) []DeviceInfo { + enumerateLock.Lock() + defer enumerateLock.Unlock() + // Gather all device infos and ensure they are freed before returning head := C.hid_enumerate(C.ushort(vendorID), C.ushort(productID)) if head == nil { |