TAO/examples/Content_Server/AMI_Observer/Callback_Handler.cpp

   1 // -*- C++ -*-
   2 // Ossama Othman <ossama@uci.edu>
   3
   4 #include "ace/FILE_Connector.h"
   5 #include "ace/Log_Msg.h"
   6 #include "Callback_Handler.h"
   7
   8 Callback_Handler::Callback_Handler (const char *pathname,
   9                                     Web_Server::Callback_ptr client_callback)
  10   : file_ (ACE_TEXT_CHAR_TO_TCHAR(pathname)),
  11     file_io_ (),
  12     callback_ (Web_Server::Callback::_duplicate (client_callback)),
  13     ami_handler_ (),
  14     chunk_ (new Web_Server::Chunk_Type),
  15     chunk_index_ (0),
  16     last_chunk_ (0)
  17 {
  18   // Nothing else
  19 }
  20
  21 Callback_Handler::~Callback_Handler ()
  22 {
  23   // Nothing else
  24 }
  25
  26 void
  27 Callback_Handler::next_chunk ()
  28 {
  29   if (this->last_chunk_ == 1)
  30     {
  31       this->deactivate ();
  32
  33       return;
  34     }
  35
  36   // Allocate a buffer for the file being read.
  37   CORBA::Octet *buf =
  38     Web_Server::Chunk_Type::allocbuf (BUFSIZ);
  39
  40   if (buf == 0)
  41     throw CORBA::NO_MEMORY ();
  42
  43   ssize_t bytes_read = this->file_io_.recv (buf,
  44                                             BUFSIZ);
  45   if (bytes_read == -1)
  46     {
  47       Web_Server::Chunk_Type::freebuf (buf);
  48
  49       throw CORBA::INTERNAL ();
  50     }
  51   else if (bytes_read == 0)
  52     {
  53       Web_Server::Chunk_Type::freebuf (buf);
  54       this->last_chunk_ = 1;
  55     }
  56   else
  57     {
  58       this->chunk_index_++;
  59
  60       ACE_DEBUG ((LM_DEBUG,
  61                   ACE_TEXT ("Sending chunk %d from %s of size <%d>\n"),
  62                   this->chunk_index_,
  63                   this->file_.get_path_name (),
  64                   bytes_read));
  65
  66       // Place the contents of the buffer into the outgoing octet
  67       // sequence.  Only replace the amount of data actually read.
  68       this->chunk_->replace (bytes_read,
  69                              bytes_read,
  70                              buf,
  71                              1);  // The sequence releases memory for us.
  72     }
  73
  74   this->callback_->sendc_next_chunk (this->ami_handler_.in (),
  75                                      this->chunk_.in (),
  76                                      this->last_chunk_);
  77 }
  78
  79 void
  80 Callback_Handler::next_chunk_excep
  81   (::Messaging::ExceptionHolder *excep_holder)
  82 {
  83   this->last_chunk_ = 1;
  84
  85   try
  86     {
  87       this->deactivate ();
  88
  89       excep_holder->raise_exception ();
  90     }
  91   catch (const CORBA::Exception& ex)
  92     {
  93       ex._tao_print_exception (
  94         ACE_TEXT ("Exception occurred during ")
  95         ACE_TEXT ("sendc_next_chunk() call:"));
  96     }
  97 }
  98
  99 void
 100 Callback_Handler::run ()
 101 {
 102   // Open the file to be downloaded
 103   this->open_file ();
 104
 105   // Activate this Reply Handler.
 106   this->ami_handler_ = this->_this ();
 107
 108   // Begin the asynchronous invocation.  Note that the AMI
 109   // "sendc_next_chunk()" call is done within the following call,
 110   // since data must first be read into the Chunk.
 111   this->next_chunk ();
 112 }
 113
 114 void
 115 Callback_Handler::open_file ()
 116 {
 117   // Create a temporary file to store the retrieved data.
 118   ACE_FILE_Connector connector;
 119
 120   if (connector.connect (this->file_io_,
 121                          this->file_,
 122                          0,
 123                          ACE_Addr::sap_any,
 124                          0,
 125                          O_RDONLY) == -1)
 126     // HTTP 1.1 "Not Found"
 127     throw Web_Server::Error_Result (404);
 128 }
 129
 130 void
 131 Callback_Handler::deactivate ()
 132 {
 133   // Close the file that was sent to the client.
 134   (void) this->file_io_.close ();
 135
 136   // Get the POA used when activating the Reply Handler object.
 137   PortableServer::POA_var poa = this->_default_POA ();
 138
 139   // Get the object ID associated with this servant.
 140   PortableServer::ObjectId_var oid =
 141     poa->servant_to_id (this);
 142
 143   // Now deactivate the AMI_CallbackHandler object.
 144   poa->deactivate_object (oid.in ());
 145 }