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