Skip to content

Commit

Permalink
Merge pull request #805 from erikarn/ahc_20201108_fix_libusb_cancel
Browse files Browse the repository at this point in the history 
Fix libusb usage for at least freebsd around the worker thread and transfer cancellation
  • Loading branch information
@mossmann
mossmann authored Jan 24, 2021
2 parents 52851ee + 61a06b9 commit ee44d2d
Showing 1 changed file with 176 additions and 37 deletions.
213 changes: 176 additions & 37 deletions host/libhackrf/src/hackrf.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -25,6 +25,9 @@ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSI

#include <stdlib.h>
#include <string.h>
#ifndef _WIN32
#include <unistd.h>
#endif
#include <libusb.h>

#ifdef _WIN32
Expand Down Expand Up @@ -119,6 +122,7 @@ struct hackrf_device {
void* tx_ctx;
volatile bool do_exit;
unsigned char buffer[TRANSFER_COUNT * TRANSFER_BUFFER_SIZE];
bool transfers_setup; /* true if the USB transfers have been setup */
};

typedef struct {
Expand Down Expand Up @@ -157,6 +161,8 @@ static const uint16_t hackrf_one_usb_pid = 0x6089;
static const uint16_t rad1o_usb_pid = 0xcc15;
static uint16_t open_devices = 0;

static int create_transfer_thread(hackrf_device* device);

static libusb_context* g_libusb_context = NULL;
int last_libusb_error = LIBUSB_SUCCESS;

Expand All @@ -165,11 +171,38 @@ static void request_exit(hackrf_device* device)
device->do_exit = true;
}

/*
* Check if the transfers are setup and owned by libusb.
*
* Returns true if the device transfers are currently setup
* in libusb, false otherwise.
*/
static int transfers_check_setup(hackrf_device* device)
{
if( (device->transfers != NULL) && (device->transfers_setup == true) )
return true;
return false;
}

/*
* Cancel any transfers that are in-flight.
*
* This cancels any transfers that hvae been given to libusb for
* either transmit or receive.
*
* This must be done whilst the libusb thread is running, as
* on some platforms cancelling transfers requires some work
* to be done inside the libusb thread to completely cancel
* pending transfers.
*
* Returns HACKRF_SUCCESS if OK, HACKRF_ERROR_OTHER if the
* transfers aren't currently setup.
*/
static int cancel_transfers(hackrf_device* device)
{
uint32_t transfer_index;

if( device->transfers != NULL )
if(transfers_check_setup(device) == true)
{
for(transfer_index=0; transfer_index<TRANSFER_COUNT; transfer_index++)
{
Expand All @@ -178,6 +211,7 @@ static int cancel_transfers(hackrf_device* device)
libusb_cancel_transfer(device->transfers[transfer_index]);
}
}
device->transfers_setup = false;
return HACKRF_SUCCESS;
} else {
return HACKRF_ERROR_OTHER;
Expand Down Expand Up @@ -269,6 +303,7 @@ static int prepare_transfers(
return HACKRF_ERROR_LIBUSB;
}
}
device->transfers_setup = true;
return HACKRF_SUCCESS;
} else {
// This shouldn't happen.
Expand Down Expand Up @@ -317,6 +352,7 @@ static int detach_kernel_drivers(libusb_device_handle* usb_device_handle)
static int set_hackrf_configuration(libusb_device_handle* usb_device, int config)
{
int result, curr_config;

result = libusb_get_configuration(usb_device, &curr_config);
if( result != 0 )
{
Expand Down Expand Up @@ -560,7 +596,7 @@ static int hackrf_open_setup(libusb_device_handle* usb_device, hackrf_device** d
}

lib_device = NULL;
lib_device = (hackrf_device*)malloc(sizeof(*lib_device));
lib_device = (hackrf_device*)calloc(1, sizeof(*lib_device));
if( lib_device == NULL )
{
libusb_release_interface(usb_device, 0);
Expand All @@ -584,6 +620,14 @@ static int hackrf_open_setup(libusb_device_handle* usb_device, hackrf_device** d
return HACKRF_ERROR_NO_MEM;
}

result = create_transfer_thread(lib_device);
if (result != 0) {
free(lib_device);
libusb_release_interface(usb_device, 0);
libusb_close(usb_device);
return result;
}

*device = lib_device;
open_devices++;

Expand Down Expand Up @@ -1483,7 +1527,7 @@ static void* transfer_threadproc(void* arg)
int error;
struct timeval timeout = { 0, 500000 };

while( (device->streaming) && (device->do_exit == false) )
while(device->do_exit == false )
{
error = libusb_handle_events_timeout(g_libusb_context, &timeout);
if( (error != 0) && (error != LIBUSB_ERROR_INTERRUPTED) )
Expand Down Expand Up @@ -1521,25 +1565,41 @@ static void LIBUSB_CALL hackrf_libusb_transfer_callback(struct libusb_transfer*
}else {
request_exit(device);
}
} else if(usb_transfer->status == LIBUSB_TRANSFER_CANCELLED) {
/* Nothing; this will happen during shutdown */
} else {
/* Other cases LIBUSB_TRANSFER_NO_DEVICE
LIBUSB_TRANSFER_ERROR, LIBUSB_TRANSFER_TIMED_OUT
LIBUSB_TRANSFER_STALL, LIBUSB_TRANSFER_OVERFLOW
LIBUSB_TRANSFER_CANCELLED ...
LIBUSB_TRANSFER_STALL, LIBUSB_TRANSFER_OVERFLOW ....
*/
request_exit(device); /* Fatal error stop transfer */
device->streaming = false;
}
}

static int kill_transfer_thread(hackrf_device* device)
{
void* value;
int result;

request_exit(device);

if( device->transfer_thread_started != false )
{
/*
* Schedule cancelling transfers before halting the
* libusb thread. This should result in the transfers
* being properly marked as cancelled.
*
* Ideally this would wait for the cancellations to
* complete with the callback but for now that
* isn't super easy to do.
*/
cancel_transfers(device);

/*
* Now call request_exit() to halt the main loop.
*/
request_exit(device);

value = NULL;
result = pthread_join(device->transfer_thread, &value);
if( result != 0 )
Expand All @@ -1548,36 +1608,50 @@ static int kill_transfer_thread(hackrf_device* device)
}
device->transfer_thread_started = false;

/* Cancel all transfers */
cancel_transfers(device);
}

/*
* Reset do_exit; we're now done here and the thread was
* already dead or is now dead.
*/
device->do_exit = false;

return HACKRF_SUCCESS;
}

static int create_transfer_thread(hackrf_device* device,
static int prepare_setup_transfers(hackrf_device* device,
const uint8_t endpoint_address,
hackrf_sample_block_cb_fn callback)
{
int result;
if( device->transfer_thread_started == false )

if( device->transfers_setup == true )
{
device->streaming = false;
device->do_exit = false;
return HACKRF_ERROR_BUSY;
}

result = prepare_transfers(
device, endpoint_address,
hackrf_libusb_transfer_callback
);
device->callback = callback;
result = prepare_transfers(
device, endpoint_address,
hackrf_libusb_transfer_callback
);

if( result != HACKRF_SUCCESS )
{
return result;
}
if( result != HACKRF_SUCCESS )
{
return result;
}

device->streaming = true;
device->callback = callback;
return HACKRF_SUCCESS;
}

static int create_transfer_thread(hackrf_device* device)
{
int result;

if( device->transfer_thread_started == false )
{
device->streaming = false;
device->do_exit = false;
result = pthread_create(&device->transfer_thread, 0, transfer_threadproc, device);
if( result == 0 )
{
Expand All @@ -1595,7 +1669,7 @@ static int create_transfer_thread(hackrf_device* device,
int ADDCALL hackrf_is_streaming(hackrf_device* device)
{
/* return hackrf is streaming only when streaming, transfer_thread_started are true and do_exit equal false */

if( (device->transfer_thread_started == true) &&
(device->streaming == true) &&
(device->do_exit == false) )
Expand All @@ -1621,24 +1695,51 @@ int ADDCALL hackrf_start_rx(hackrf_device* device, hackrf_sample_block_cb_fn cal
{
int result;
const uint8_t endpoint_address = LIBUSB_ENDPOINT_IN | 1;
device->rx_ctx = rx_ctx;
result = hackrf_set_transceiver_mode(device, HACKRF_TRANSCEIVER_MODE_RECEIVE);
if( result == HACKRF_SUCCESS )
{
device->rx_ctx = rx_ctx;
result = create_transfer_thread(device, endpoint_address, callback);
result = prepare_setup_transfers(device, endpoint_address, callback);
}
if (result == HACKRF_SUCCESS) {
device->streaming = true;
}
return result;
}

static int hackrf_stop_rx_cmd(hackrf_device* device)
{
int result;

result = hackrf_set_transceiver_mode(device, HACKRF_TRANSCEIVER_MODE_OFF);
#ifdef _WIN32
Sleep(10);
#else
usleep(10 * 1000);
#endif
return result;
}

/*
* Stop any pending receive.
*
* This call stops transfers and halts recieve if it is enabled.
*
* It returns HACKRF_SUCCESS if receive was started and it was
* properly stopped, an error otherwise.
*/
int ADDCALL hackrf_stop_rx(hackrf_device* device)
{
int result;
result = kill_transfer_thread(device);

device->streaming = false;
result = cancel_transfers(device);
if (result != HACKRF_SUCCESS)
{
return result;
}
return hackrf_set_transceiver_mode(device, HACKRF_TRANSCEIVER_MODE_OFF);

return hackrf_stop_rx_cmd(device);
}

int ADDCALL hackrf_start_tx(hackrf_device* device, hackrf_sample_block_cb_fn callback, void* tx_ctx)
Expand All @@ -1649,34 +1750,65 @@ int ADDCALL hackrf_start_tx(hackrf_device* device, hackrf_sample_block_cb_fn cal
if( result == HACKRF_SUCCESS )
{
device->tx_ctx = tx_ctx;
result = create_transfer_thread(device, endpoint_address, callback);
result = prepare_setup_transfers(device, endpoint_address, callback);
}
if (result == HACKRF_SUCCESS) {
device->streaming = true;
}
return result;
}

static int hackrf_stop_tx_cmd(hackrf_device* device)
{
int result;
result = hackrf_set_transceiver_mode(device, HACKRF_TRANSCEIVER_MODE_OFF);
#ifdef _WIN32
Sleep(10);
#else
usleep(10 * 1000);
#endif
return result;
}

/*
* Stop any pending transmit.
*
* This call stops transfers and halts transmit if it is enabled.
*
* It returns HACKRF_SUCCESS if receive was started and it was
* properly stopped, an error otherwise.
*/
int ADDCALL hackrf_stop_tx(hackrf_device* device)
{
int result;
result = kill_transfer_thread(device);
device->streaming = false;
result = cancel_transfers(device);
if (result != HACKRF_SUCCESS)
{
return result;
}

return hackrf_set_transceiver_mode(device, HACKRF_TRANSCEIVER_MODE_OFF);
return hackrf_stop_tx_cmd(device);
}

int ADDCALL hackrf_close(hackrf_device* device)
{
int result1, result2;
int result1, result2, result3;

result1 = HACKRF_SUCCESS;
result2 = HACKRF_SUCCESS;

result3 = HACKRF_SUCCESS;

if( device != NULL )
{
result1 = hackrf_stop_rx(device);
result2 = hackrf_stop_tx(device);
result1 = hackrf_stop_rx_cmd(device);
result2 = hackrf_stop_tx_cmd(device);

/*
* Finally kill the transfer thread, which will
* also cancel any pending transmit/receive transfers.
*/
result3 = kill_transfer_thread(device);
if( device->usb_device != NULL )
{
libusb_release_interface(device->usb_device, 0);
Expand All @@ -1690,6 +1822,10 @@ int ADDCALL hackrf_close(hackrf_device* device)
}
open_devices--;

if (result3 != HACKRF_SUCCESS)
{
return result3;
}
if (result2 != HACKRF_SUCCESS)
{
return result2;
Expand Down Expand Up @@ -2174,7 +2310,10 @@ int ADDCALL hackrf_start_rx_sweep(hackrf_device* device, hackrf_sample_block_cb_
if (HACKRF_SUCCESS == result)
{
device->rx_ctx = rx_ctx;
result = create_transfer_thread(device, endpoint_address, callback);
result = prepare_setup_transfers(device, endpoint_address, callback);
}
if (result == HACKRF_SUCCESS) {
device->streaming = true;
}
return result;
}
Expand Down

0 comments on commit ee44d2d

Please sign in to comment.