1 files changed, 232 insertions, 0 deletions
diff --git a/libtiutils/Semaphore.cpp b/libtiutils/Semaphore.cpp
new file mode 100644
index 0000000..37f3a89
--- /dev/null
+++ b/libtiutils/Semaphore.cpp
@@ -0,0 +1,232 @@
+/*
+ * Copyright (C) Texas Instruments - http://www.ti.com/
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+
+#include "Semaphore.h"
+#include "ErrorUtils.h"
+#include <utils/Log.h>
+#include <time.h>
+
+namespace android {
+
+/**
+   @brief Constructor for the semaphore class
+
+   @param none
+   @return none
+ */
+Semaphore::Semaphore()
+{
+    ///Initialize the semaphore to NULL
+    mSemaphore = NULL;
+}
+
+/**
+   @brief Destructor of the semaphore class
+
+   @param none
+   @return none
+
+ */
+Semaphore::~Semaphore()
+{
+    Release();
+}
+
+/**
+   @brief: Releases semaphore
+
+   @param count >=0
+   @return NO_ERROR On Success
+   @return One of the android error codes based on semaphore de-initialization
+ */
+
+status_t Semaphore::Release()
+{
+    int status = 0;
+
+    ///Destroy only if the semaphore has been created
+    if(mSemaphore)
+        {
+        status = sem_destroy(mSemaphore);
+
+        free(mSemaphore);
+
+        mSemaphore = NULL;
+        }
+
+    ///Initialize the semaphore and return the status
+    return ErrorUtils::posixToAndroidError(status);
+
+}
+
+/**
+   @brief Create the semaphore with initial count value
+
+   @param count >=0
+   @return NO_ERROR On Success
+   @return NO_MEMORY If unable to allocate memory for the semaphore
+   @return BAD_VALUE If an invalid count value is passed (<0)
+   @return One of the android error codes based on semaphore initialization
+ */
+
+status_t Semaphore::Create(int count)
+{
+    status_t ret = NO_ERROR;
+
+    ///count cannot be less than zero
+    if(count<0)
+        {
+        return BAD_VALUE;
+        }
+
+    ret = Release();
+    if ( NO_ERROR != ret )
+        {
+        return ret;
+        }
+
+    ///allocate memory for the semaphore
+    mSemaphore = (sem_t*)malloc(sizeof(sem_t)) ;
+
+    ///if memory is unavailable, return error
+    if(!mSemaphore)
+        {
+        return NO_MEMORY;
+        }
+
+    ///Initialize the semaphore and return the status
+    return ErrorUtils::posixToAndroidError(sem_init(mSemaphore, 0x00, count));
+
+}
+
+/**
+   @brief Wait operation
+
+   @param none
+   @return BAD_VALUE if the semaphore is not initialized
+   @return NO_ERROR On success
+   @return One of the android error codes based on semaphore wait operation
+ */
+status_t Semaphore::Wait()
+{
+    ///semaphore should have been created first
+    if(!mSemaphore)
+        {
+        return BAD_VALUE;
+        }
+
+    ///Wait and return the status after signalling
+    return ErrorUtils::posixToAndroidError(sem_wait(mSemaphore));
+
+
+}
+
+
+/**
+   @brief Signal operation
+
+   @param none
+     @return BAD_VALUE if the semaphore is not initialized
+     @return NO_ERROR On success
+     @return One of the android error codes based on semaphore signal operation
+   */
+
+status_t Semaphore::Signal()
+{
+    ///semaphore should have been created first
+    if(!mSemaphore)
+        {
+        return BAD_VALUE;
+        }
+
+    ///Post to the semaphore
+    return ErrorUtils::posixToAndroidError(sem_post(mSemaphore));
+
+}
+
+/**
+   @brief Current semaphore count
+
+   @param none
+   @return Current count value of the semaphore
+ */
+int Semaphore::Count()
+{
+    int val;
+
+    ///semaphore should have been created first
+    if(!mSemaphore)
+        {
+        return BAD_VALUE;
+        }
+
+    ///get the value of the semaphore
+    sem_getvalue(mSemaphore, &val);
+
+    return val;
+}
+
+/**
+   @brief Wait operation with a timeout
+
+     @param timeoutMicroSecs The timeout period in micro seconds
+     @return BAD_VALUE if the semaphore is not initialized
+     @return NO_ERROR On success
+     @return One of the android error codes based on semaphore wait operation
+   */
+
+status_t Semaphore::WaitTimeout(int timeoutMicroSecs)
+{
+    status_t ret = NO_ERROR;
+
+    struct timespec timeSpec;
+    struct timeval currentTime;
+
+    ///semaphore should have been created first
+    if( NULL == mSemaphore)
+        {
+        ret = BAD_VALUE;
+        }
+
+    if ( NO_ERROR == ret )
+        {
+
+        ///setup the timeout values - timeout is specified in seconds and nanoseconds
+        gettimeofday(&currentTime, NULL);
+        timeSpec.tv_sec = currentTime.tv_sec;
+        timeSpec.tv_nsec = currentTime.tv_usec * 1000;
+        timeSpec.tv_sec += ( timeoutMicroSecs / 1000000 );
+        timeSpec.tv_nsec += ( timeoutMicroSecs % 1000000) * 1000;
+
+        ///Wait for the timeout or signal and return the result based on whichever event occurred first
+        ret = sem_timedwait(mSemaphore, &timeSpec);
+        }
+
+    if ( NO_ERROR != ret )
+      {
+        Signal();
+        Create(0);
+      }
+
+    return ret;
+}
+
+
+};
+
+