Internal changes in the base CComm class to improve the efficiency of the data handling.

src/CMakeLists.txt

@@ -33,9 +33,9 @@ ELSE(FTDI_INCLUDE_DIR AND FTDI_LIBRARY)
 ENDIF(FTDI_INCLUDE_DIR AND FTDI_LIBRARY)
 
 # edit the following line to add all the source code files of the library
-SET(sources ./comm.cpp ./commexceptions.cpp ./serial/rs232.cpp ./serial/rs232exceptions.cpp  ./sockets/socket.cpp ./sockets/socketclient.cpp ./sockets/socketserver.cpp ./sockets/socketexceptions.cpp ./can/can.cpp)
+SET(sources ./comm.cpp ./cqueue.cpp ./commexceptions.cpp ./serial/rs232.cpp ./serial/rs232exceptions.cpp  ./sockets/socket.cpp ./sockets/socketclient.cpp ./sockets/socketserver.cpp ./sockets/socketexceptions.cpp ./can/can.cpp)
 # edit the following line to add all the header files of the library
-SET(headers ./comm.h ./commexceptions.h ./serial/rs232.h ./serial/rs232exceptions.h ./sockets/socket.h ./sockets/socketclient.h ./sockets/socketserver.h ./sockets/socketexceptions.h ./can/can.h)
+SET(headers ./comm.h ./cqueue.h ./commexceptions.h ./serial/rs232.h ./serial/rs232exceptions.h ./sockets/socket.h ./sockets/socketclient.h ./sockets/socketserver.h ./sockets/socketexceptions.h ./can/can.h)
 
 IF(BUILD_FTDI)
   SET(sources ${sources} ./usb_ftdi/ftdiserver.cpp ./usb_ftdi/ftdimodule.cpp ./usb_ftdi/ftdiexceptions.cpp)

src/comm.cpp

@@ -105,8 +105,7 @@ void CComm::config(void *config)
 
 int CComm::read(unsigned char *data,int len)
 {
-  int num_available=0;
-  int i=0;
+  int num_read=0;
 
   if(data==NULL)
   {
@@ -118,17 +117,12 @@ int CComm::read(unsigned char *data,int len)
     if(this->state==configured || this->state==sending)
     {
       this->access_comm.enter();
-      num_available=this->receive_queue.size();
-      if(len>num_available)
+      num_read=this->receive_queue.read(data,len);
+      if(len>num_read)
       {
-        len=num_available;
+        len=num_read;
         this->event_server->reset_event(this->rx_event_id);
       }
-      for(i=0;i<len;i++)
-      {
-        data[i]=*this->receive_queue.begin();
-        this->receive_queue.pop_front();
-      }
       this->access_comm.exit();
       return len;
     }
@@ -186,7 +180,7 @@ unsigned int CComm::get_num_data(void)
   if(this->state==configured || this->state==sending)
   {
     this->access_comm.enter();
-    num=this->receive_queue.size();
+    num=this->receive_queue.get_num_data();
     this->access_comm.exit();
   }
 
@@ -230,7 +224,7 @@ void CComm::close(void)
       throw;
     }
     /* flush the data queues */
-    this->receive_queue.erase(this->receive_queue.begin(),this->receive_queue.end());
+    this->receive_queue.flush();
     /* change the current state */
     this->state=created;
     this->access_comm.exit();
@@ -271,7 +265,7 @@ void *CComm::comm_thread(void *param)
 void CComm::on_receive(void)
 {
   unsigned char *data=NULL;
-  int num=0,num_read=0,i=0;
+  int num=0,num_read=0;
 
   if((num=this->hard_get_num_data())==-1)
   {
@@ -295,8 +289,7 @@ void CComm::on_receive(void)
     }
     else
     {
-      for(i=0;i<num;i++)
-        this->receive_queue.push_back(data[i]);
+      this->receive_queue.write(data,num);
       if(!this->event_server->event_is_set(this->rx_event_id))
       {
         this->event_server->set_event(this->rx_event_id);

src/comm.h

@@ -5,6 +5,7 @@
 #include "eventserver.h"
 #include "threadserver.h"
 #include "mutex.h"
+#include "cqueue.h"
 
 typedef enum {created,configured,opened,sending} comm_states;
 
@@ -135,7 +136,7 @@ class CComm
      * function get_num_data() returns the number of bytes in this queue. By default,
      * this queue is empty.
      */
-    std::list<unsigned char> receive_queue;
+    CQueue receive_queue;
     /**
      * \brief current state of the communication device
      * 

src/cqueue.cpp

+#include "cqueue.h"
+
+CQueue::CQueue()
+{
+  this->size=QUEUE_DEFAULT_SIZE;
+  this->data=new unsigned char[this->size];
+  this->num_data=0;
+  this->read_pointer=0;
+  this->write_pointer=0;
+}
+
+CQueue::CQueue(int size)
+{
+  this->size=size;
+  this->data=new unsigned char[this->size];
+  this->num_data=0;
+  this->read_pointer=0;
+  this->write_pointer=0;
+}
+
+void CQueue::resize(int new_size)
+{
+}
+
+int CQueue::read(unsigned char *data,int len)
+{
+  int num_data_to_end=0;
+
+  this->queue_access.enter();
+  if(len>this->num_data)
+    len=this->num_data;
+  num_data_to_end=this->size-this->read_pointer;
+  if(num_data_to_end<len)
+  {
+    memcpy(data,&this->data[read_pointer],num_data_to_end);
+    memcpy(&data[num_data_to_end],this->data,len-num_data_to_end);
+    this->read_pointer=len-num_data_to_end;
+    this->num_data-=len;
+  } 
+  else
+  {
+    memcpy(data,&this->data[this->read_pointer],len);
+    this->read_pointer+=len;
+    this->num_data-=len;
+  }
+  this->queue_access.exit();
+
+  return len;  
+}
+
+int CQueue::write(unsigned char *data,int len)
+{
+  int num_data_to_end=0;
+  
+  this->queue_access.enter();
+  if(len>(this->size-this->num_data))
+    len=this->size-this->num_data;
+  num_data_to_end=this->size-this->write_pointer;
+  if(num_data_to_end<len)
+  {
+    memcpy(&this->data[this->write_pointer],data,num_data_to_end);
+    memcpy(this->data,&data[num_data_to_end],len-num_data_to_end);
+    this->write_pointer=len-num_data_to_end;
+    this->num_data+=len;
+  }
+  else
+  {
+    memcpy(&this->data[this->write_pointer],data,len);
+    this->write_pointer+=len;
+    this->num_data+=len;
+  }
+  this->queue_access.exit();
+
+  return len;
+}
+
+int CQueue::get_num_data(void)
+{
+  return this->num_data;
+}
+
+bool CQueue::is_empty(void)
+{
+  if(this->num_data==0)
+    return true;
+  else
+    return false;
+}
+
+bool CQueue::is_full(void)
+{
+  if(this->num_data==this->size)
+    return true;
+  else
+    return false;
+}
+
+void CQueue::flush(void)
+{
+  this->queue_access.enter();
+  this->read_pointer=0;
+  this->write_pointer=0;
+  this->num_data=0;
+  this->queue_access.exit();
+}
+
+CQueue::~CQueue()
+{
+  if(this->data!=NULL)
+  {
+    delete[] this->data;
+    this->data=NULL;
+  }
+  this->num_data=0;
+  this->read_pointer=0;
+  this->write_pointer=0;
+}
+

src/cqueue.h

+#ifndef _CQUEUE_H
+#define _CQUEUE_H
+
+#include <string.h>
+#include "mutex.h"
+
+#define QUEUE_DEFAULT_SIZE     1024
+
+class CQueue
+{
+  private:
+    int size;
+    int num_data;
+    int read_pointer;
+    int write_pointer;
+    unsigned char *data;
+    CMutex queue_access;
+  public:
+    CQueue();
+    CQueue(int size);
+    void resize(int new_size);
+    int read(unsigned char *data,int len);
+    int write(unsigned char *data,int len);
+    int get_num_data(void);
+    bool is_empty(void);
+    bool is_full(void);
+    void flush(void);
+    ~CQueue();
+};
+
+#endif