adb: libusb: switch from polling for accessibility to a sleep.

For unclear reasons, it seems that for some people, devices are
becoming accessible, inaccessible, and then inaccessible again.
Switch to a sleep for now.

Bug: http://b/62200735
Test: manual
Merged-In: Id51dcb188c3534a57c35cbfd30a181c99115a23c
Change-Id: Id51dcb188c3534a57c35cbfd30a181c99115a23c
(cherry picked from commit 5b8b10e078)
This commit is contained in:
Josh Gao 2017-06-01 15:42:26 -07:00
parent f74dd42e4e
commit fd79f01baf

View file

@ -180,10 +180,6 @@ static std::string get_device_dev_path(libusb_device* device) {
if (port_count < 0) return "";
return StringPrintf("/dev/bus/usb/%03u/%03u", libusb_get_bus_number(device), ports[0]);
}
static bool is_device_accessible(libusb_device* device) {
return access(get_device_dev_path(device).c_str(), R_OK | W_OK) == 0;
}
#endif
static bool endpoint_is_output(uint8_t endpoint) {
@ -389,18 +385,12 @@ static std::atomic<int> connecting_devices(0);
static void device_connected(libusb_device* device) {
#if defined(__linux__)
// Android's host linux libusb uses netlink instead of udev for device hotplug notification,
// which means we can get hotplug notifications before udev has updated ownership/perms on
// the device. Since we're not going to be able to link against the system's libudev any
// time soon, hack around this by checking for accessibility in a loop.
// which means we can get hotplug notifications before udev has updated ownership/perms on the
// device. Since we're not going to be able to link against the system's libudev any time soon,
// hack around this by inserting a sleep.
auto thread = std::thread([device]() {
std::string device_path = get_device_dev_path(device);
auto start = std::chrono::steady_clock::now();
while (std::chrono::steady_clock::now() - start < 500ms) {
if (is_device_accessible(device)) {
break;
}
std::this_thread::sleep_for(10ms);
}
std::this_thread::sleep_for(1s);
process_device(device);
if (--connecting_devices == 0) {