Files
allwpilib/wpilibj/wpilibJavaJNI/lib/CANJNI.cpp
Peter Johnson 7023013c4b Simplify JNI interfaces.
These changes both simplify the Java code and improve performance across the
JNI boundary.

This also fixes the AnalogCrossConnectTest by adding delays to
setInterruptHigh() and setInterruptLow() to ensure the change in voltage has
time to propagate and extends the timeouts in AbstractInterruptTest.

Detailed changes:

Hoisted status checks to C.  This avoids the need to create direct byte
buffers (expensive) and significantly simplifies the Java code.  The C code
now directly generates the exception or reports the error to the DS.

The JVM pointer is now a global across the JNI, initialized by the OnLoad
function, avoiding the need for some of the class-specific initializers to
get this pointer for callbacks.

Opaque pointers (such as ports) are now passed as long values rather than
with a ByteBuffer wrapper.

Added extern "C" to source files.  This allows earlier detection of JNI
definition mismatches to the Java source headers.

Changed JNI signatures to more closely match HAL signatures (in particular,
boolean is now universally used instead of byte for HAL bool, which cleans
up mapping back and forth to 1/0 from true/false).

Change-Id: I4ea0032cabb0871cd74106a3a70d947258c29d2d
2015-11-06 09:04:22 -08:00

106 lines
3.2 KiB
C++

#include <jni.h>
#include <assert.h>
#include "Log.hpp"
#include "edu_wpi_first_wpilibj_can_CANJNI.h"
#include "HAL/CAN.hpp"
#include "FRC_NetworkCommunication/CANSessionMux.h"
#include "HALUtil.h"
// set the logging level
//TLogLevel canJNILogLevel = logDEBUG;
TLogLevel canJNILogLevel = logERROR;
#define CANJNI_LOG(level) \
if (level > canJNILogLevel) ; \
else Log().Get(level)
extern "C" {
/*
* Class: edu_wpi_first_wpilibj_can_CANJNI
* Method: FRCNetworkCommunicationCANSessionMuxSendMessage
* Signature: (ILjava/nio/ByteBuffer;I)V
*/
JNIEXPORT void JNICALL Java_edu_wpi_first_wpilibj_can_CANJNI_FRCNetworkCommunicationCANSessionMuxSendMessage
(JNIEnv * env, jclass, jint messageID, jobject data, jint periodMs)
{
CANJNI_LOG(logDEBUG) << "Calling CANJNI FRCNetworkCommunicationCANSessionMuxSendMessage";
uint8_t *dataBuffer = (uint8_t *)(data? env->GetDirectBufferAddress(data) : 0);
uint8_t dataSize = (uint8_t)(data? env->GetDirectBufferCapacity(data) : 0);
CANJNI_LOG(logDEBUG) << "Message ID " << std::hex << messageID;
if(logDEBUG <= canJNILogLevel)
{
if(dataBuffer)
{
std::ostringstream str;
str << std::setfill('0') << std::hex;
for(int i = 0; i < dataSize; i++)
{
str << std::setw(2) << (int)dataBuffer[i] << ' ';
}
Log().Get(logDEBUG) << "Data: " << str.str();
}
else
{
CANJNI_LOG(logDEBUG) << "Data: null";
}
}
CANJNI_LOG(logDEBUG) << "Period: " << periodMs;
int32_t status = 0;
FRC_NetworkCommunication_CANSessionMux_sendMessage(messageID, dataBuffer, dataSize, periodMs, &status);
CANJNI_LOG(logDEBUG) << "Status: " << status;
CheckCANStatus(env, status, messageID);
}
static uint8_t buffer[8];
/*
* Class: edu_wpi_first_wpilibj_can_CANJNI
* Method: FRCNetworkCommunicationCANSessionMuxReceiveMessage
* Signature: (Ljava/nio/IntBuffer;ILjava/nio/ByteBuffer;)Ljava/nio/ByteBuffer;
*/
JNIEXPORT jobject JNICALL Java_edu_wpi_first_wpilibj_can_CANJNI_FRCNetworkCommunicationCANSessionMuxReceiveMessage
(JNIEnv * env, jclass, jobject messageID, jint messageIDMask, jobject timeStamp)
{
CANJNI_LOG(logDEBUG) << "Calling CANJNI FRCNetworkCommunicationCANSessionMuxReceiveMessage";
uint32_t *messageIDPtr = (uint32_t *)env->GetDirectBufferAddress(messageID);
uint32_t *timeStampPtr = (uint32_t *)env->GetDirectBufferAddress(timeStamp);
uint8_t dataSize = 0;
int32_t status = 0;
FRC_NetworkCommunication_CANSessionMux_receiveMessage(messageIDPtr, messageIDMask, buffer, &dataSize, timeStampPtr, &status);
CANJNI_LOG(logDEBUG) << "Message ID " << std::hex << *messageIDPtr;
if(logDEBUG <= canJNILogLevel)
{
std::ostringstream str;
str << std::setfill('0') << std::hex;
for(int i = 0; i < dataSize; i++)
{
str << std::setw(2) << (int)buffer[i] << ' ';
}
Log().Get(logDEBUG) << "Data: " << str.str();
}
CANJNI_LOG(logDEBUG) << "Timestamp: " << *timeStampPtr;
CANJNI_LOG(logDEBUG) << "Status: " << status;
if (!CheckCANStatus(env, status, *messageIDPtr)) return nullptr;
return env->NewDirectByteBuffer(buffer, dataSize);
}
} // extern "C"