embox

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/**
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 * @file
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 * @brief
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 *
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 * @date 14.01.13
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 * @author Alexander Kalmuk
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 */
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#include <javacall_events.h>
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#include <sys/select.h>
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#include <sys/time.h>
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#include <unistd.h>
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#include <kernel/thread/sync/mutex.h>
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/**
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 * Note:
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 * We made send/recv operations throw pipe between kernel task and java task.
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 * That means any another tasks could not send/recv events.
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 * */
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static int java_pipe[2];
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static struct mutex java_global_mutex;
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javacall_result javacall_event_send(unsigned char* binaryBuffer,
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                                    int binaryBufferLen) {
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	mutex_lock(&java_global_mutex);
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	{
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		/* blocking writing */
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		write(java_pipe[1], &binaryBufferLen, 4);
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		write(java_pipe[1], binaryBuffer, binaryBufferLen);
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	}
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	mutex_unlock(&java_global_mutex);
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	return JAVACALL_OK;
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}
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javacall_result javacall_event_receive(
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                            long                    timeToWaitInMillisec, /* XXX unused*/
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                            /*OUT*/ unsigned char*  binaryBuffer,
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                            int                     binaryBufferMaxLen,
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                            /*OUT*/ int*            outEventLen) {
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	size_t actual_size;
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	struct timeval timeout;
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	fd_set readfds;
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	javacall_result res = JAVACALL_OK;
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	int fd_cnt = 0;
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	FD_ZERO(&readfds);
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	FD_SET(java_pipe[0], &readfds);
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	timeout.tv_sec = timeToWaitInMillisec / 1000;
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	timeout.tv_usec = (timeToWaitInMillisec % 1000) * 1000;
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	fd_cnt = select(java_pipe[0] + 1, &readfds, NULL, NULL, &timeout);
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	if (fd_cnt != 1) {
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		res = JAVACALL_FAIL;
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		goto out;
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	}
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	read(java_pipe[0], &actual_size, 4);
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	if (actual_size > binaryBufferMaxLen) {
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		res = JAVACALL_OUT_OF_MEMORY;
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		actual_size = binaryBufferMaxLen;
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	}
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	*outEventLen = read(java_pipe[0], binaryBuffer, actual_size);
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out:
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	return res;
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}
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javacall_result javacall_create_event_queue_lock(void) {
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	return JAVACALL_OK;
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}
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javacall_result javacall_wait_and_lock_event_queue(void) {
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	mutex_lock(&java_global_mutex);
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	return JAVACALL_OK;
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}
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javacall_result javacall_unlock_event_queue(void) {
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	mutex_unlock(&java_global_mutex);
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	return JAVACALL_OK;
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}
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javacall_result javacall_destroy_event_queue_lock(void) {
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	return JAVACALL_OK;
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}
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javacall_result javacall_events_init(void) {
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	if (-1 == pipe(java_pipe)) {
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		return JAVACALL_FAIL;
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	}
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	mutex_init(&java_global_mutex);
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	return JAVACALL_OK;
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}
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