TAO/examples/Callback_Quoter/Consumer_Input_Handler.cpp

   1 //=============================================================================
   2 /**
   3  *  @file    Consumer_Input_Handler.cpp
   4  *
   5  *  Implementation of the Consumer_Input_Handler class.
   6  *
   7  *  @author Kirthika Parameswaran <kirthika@cs.wustl.edu>
   8  */
   9 //=============================================================================
  10
  11
  12 #include "Consumer_Input_Handler.h"
  13 #include "ace/Read_Buffer.h"
  14 #include "ace/OS_NS_unistd.h"
  15 #include "ace/OS_NS_ctype.h"
  16
  17 Consumer_Input_Handler::Consumer_Input_Handler (Consumer_Handler *consumer_handler)
  18   {
  19     consumer_handler_ = consumer_handler;
  20
  21   }
  22
  23 int
  24 Consumer_Input_Handler::handle_input (ACE_HANDLE)
  25 {
  26   char buf[BUFSIZ];
  27
  28   // The string could read contains \n\0 hence using ACE_OS::read
  29   // which returns the no of bytes read and hence i can manipulate
  30   // and remove the devil from the picture i.e '\n' ! ;)
  31
  32   ssize_t strlen = ACE_OS::read (ACE_STDIN,
  33                                  buf,
  34                                  sizeof buf);
  35   if (buf[strlen -1] == '\n')
  36     buf[strlen -1] = '\0';
  37
  38   switch (ACE_OS::ace_tolower (buf[0]))
  39     {
  40     case Consumer_Input_Handler::REGISTER:
  41       {
  42         this->register_consumer ();
  43         break;
  44       }
  45     case Consumer_Input_Handler::UNREGISTER:
  46       {
  47         this->unregister_consumer ();
  48         break;
  49       }
  50     case Consumer_Input_Handler::EXIT:
  51       {
  52         this->quit_consumer_process ();
  53         break;
  54       }
  55     }
  56   return 0;
  57 }
  58
  59
  60 int
  61 Consumer_Input_Handler::register_consumer ()
  62 {
  63
  64   // Get the stockname the consumer is interested in.
  65   static char stockname[BUFSIZ];
  66
  67   ACE_DEBUG ((LM_DEBUG,
  68               "Stockname?"));
  69
  70   ssize_t strlen = ACE_OS::read (ACE_STDIN,
  71                                  stockname,
  72                                  sizeof stockname - 1);
  73
  74   // Taking care of platforms where an carriage return is padded with newline.
  75   if (stockname[strlen -2] == '\n' || stockname[strlen -2] == '\r')
  76     stockname[strlen -2] = '\0';
  77   else
  78     if (stockname[strlen -1] == '\n' || stockname[strlen -1] == '\r')
  79       stockname[strlen -1] = '\0';
  80
  81
  82   this->consumer_handler_->stock_name_ = stockname;
  83
  84   // Get the threshold value.
  85   char needed_stock_value[BUFSIZ];
  86   ACE_DEBUG ((LM_DEBUG,
  87               "Threshold Stock value?"));
  88
  89   strlen = ACE_OS::read (ACE_STDIN,
  90                          needed_stock_value,
  91                          sizeof needed_stock_value);
  92
  93   if (needed_stock_value[strlen -1] == '\n')
  94     needed_stock_value[strlen -1] = '\0';
  95
  96   this->consumer_handler_->threshold_value_ =
  97     ACE_OS::atoi (needed_stock_value);
  98
  99
 100   try
 101     {
 102
 103       // Register with the server.
 104       this->consumer_handler_->server_->register_callback (this->consumer_handler_->stock_name_.c_str (),
 105                                                            this->consumer_handler_->threshold_value_,
 106                                                            this->consumer_handler_->consumer_var_.in ());
 107
 108       // Note the registration.
 109       consumer_handler_->registered_ = 1;
 110       consumer_handler_->unregistered_ = 0;
 111
 112       // @@ Up to this point..
 113
 114       ACE_DEBUG ((LM_DEBUG,
 115                   "registeration done!\n"));
 116     }
 117   catch (const CORBA::Exception& ex)
 118     {
 119       ex._tao_print_exception (
 120         "Consumer_Input_Handler::register_consumer()\n");
 121       return -1;
 122     }
 123
 124 return 0;
 125 }
 126
 127
 128
 129 int
 130 Consumer_Input_Handler::unregister_consumer ()
 131 {
 132   // Only if the consumer is registered can the
 133   // unregistration take place.
 134
 135   if (consumer_handler_->registered_ == 1)
 136     {
 137       this->consumer_handler_->server_->unregister_callback (this->consumer_handler_->consumer_var_.in());
 138
 139       ACE_DEBUG ((LM_DEBUG,
 140                   " Consumer Unregistered \n"));
 141       consumer_handler_->unregistered_ = 1;
 142       consumer_handler_->registered_ = 0;
 143     }
 144   else
 145     ACE_DEBUG ((LM_DEBUG,
 146                 " Invalid Operation: Consumer not Registered\n"));
 147
 148
 149   return 0;
 150 }
 151
 152 int
 153 Consumer_Input_Handler::quit_consumer_process ()
 154 {
 155   // Only if the consumer is registered and wants to shut
 156   // down, its necessary to unregister and then shutdown.
 157
 158
 159   try
 160     {
 161       if (consumer_handler_->unregistered_ != 1 && consumer_handler_->registered_ == 1)
 162         {
 163           // If the notifier has exited and the consumer tries to call
 164           // the unregister_callback method tehn an exception will be
 165           // raised. Hence check for this case using.
 166           this->consumer_handler_->server_->unregister_callback (this->consumer_handler_->consumer_var_.in ());
 167
 168           ACE_DEBUG ((LM_DEBUG,
 169                       " Consumer Unregistered \n"));
 170           consumer_handler_->unregistered_ = 0;
 171           consumer_handler_->registered_ = 0;
 172         }
 173       this->consumer_handler_->consumer_servant_->shutdown ();
 174     }
 175   catch (const CORBA::Exception& ex)
 176     {
 177       // There would be an exception only if there is a communication
 178       // failure between the notifier and consumer. On catching the
 179       // exception proclaim the problem and do a graceful exit.
 180       ex._tao_print_exception ("Communication failed!\n");
 181
 182       try
 183         {
 184           this->consumer_handler_->consumer_servant_->shutdown ();
 185         }
 186       catch (const CORBA::Exception&)
 187         {
 188         }
 189
 190       return -1;
 191     }
 192
 193   return 0;
 194 }
 195
 196 Consumer_Input_Handler::~Consumer_Input_Handler (void)
 197 {
 198   // No-op
 199 }