TAO/examples/Content_Server/AMI_Iterator/Iterator_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 "ace/Process_Manager.h"
   7 #include "Iterator_Handler.h"
   8 #include "ace/OS_NS_strings.h"
   9 #include "ace/OS_NS_string.h"
  10
  11 Iterator_Handler::Iterator_Handler ()
  12   : file_ (ACE_sap_any_cast (const ACE_FILE_Addr &)),
  13     file_io_ (),
  14     contents_ (),
  15     metadata_ (),
  16     offset_ (0),
  17     ami_handler_ (),
  18     request_count_ (0)
  19 {
  20   // Nothing else
  21 }
  22
  23 Iterator_Handler::~Iterator_Handler ()
  24 {
  25   (void) this->file_io_.close ();
  26 }
  27
  28 void
  29 Iterator_Handler::next_chunk (CORBA::Boolean pending_data,
  30                               const Web_Server::Chunk_Type &chunk_data)
  31 {
  32   if (pending_data)
  33     {
  34       Web_Server::Chunk_Type_var chunk = chunk_data;
  35
  36       // Append the received data to the corresponding
  37       // buffer/temporary file.
  38       if (this->file_io_.send (chunk->get_buffer (),
  39                                chunk->length ()) == -1)
  40         {
  41           ACE_ERROR ((LM_ERROR,
  42                       ACE_TEXT ("%p\n"),
  43                       ACE_TEXT ("Unable to write retrieved data to ")
  44                       ACE_TEXT ("file")));
  45           return;
  46         }
  47       else
  48         this->offset_ += chunk->length ();
  49
  50       this->contents_->sendc_next_chunk (this->ami_handler_.in (),
  51                                          this->offset_);
  52     }
  53   else
  54     {
  55       ACE_DEBUG ((LM_INFO,
  56                   ACE_TEXT ("Wrote retrieved data to file <%s>\n"),
  57                   this->file_.get_path_name ()));
  58
  59       (*this->request_count_)--;  // No more data.
  60
  61       // Done with the iterator, so destroy it.
  62       this->contents_->sendc_destroy (this->ami_handler_.in ());
  63
  64       // File retrieval has completed, so spawn an external viewer to
  65       // display its contents.
  66
  67       (void) this->spawn_viewer ();
  68     }
  69 }
  70 void
  71 Iterator_Handler::destroy ()
  72 {
  73   // Deactivate this reply handler.
  74   this->deactivate ();
  75 }
  76
  77
  78 void
  79 Iterator_Handler::run (int *request_count,
  80                        const char *pathname,
  81                        Web_Server::Iterator_Factory_ptr factory)
  82 {
  83   if (request_count != 0)
  84       this->request_count_ = request_count;
  85   else
  86     // @@ Application code shouldn't throw system exceptions.
  87     throw CORBA::BAD_PARAM ();
  88   // Initialize the Content Iterator
  89   this->initialize_content_iterator (pathname,
  90                                      factory);
  91
  92   // Activate this Reply Handler.
  93   this->ami_handler_ = this->_this ();
  94
  95   // Begin the asynchronous invocation.
  96   this->contents_->sendc_next_chunk (this->ami_handler_.in (),
  97                                      this->offset_);
  98 }
  99
 100 void
 101 Iterator_Handler::initialize_content_iterator
 102   (const char *pathname,
 103    Web_Server::Iterator_Factory_ptr factory)
 104 {
 105   // Obtain a Content Iterator for the desired file.
 106   factory->get_iterator (pathname,
 107                          this->contents_,
 108                          this->metadata_);
 109
 110   // Create a temporary file to store the retrieved data.
 111   ACE_FILE_Connector connector;
 112
 113   if (connector.connect (this->file_io_,
 114                          this->file_,
 115                          0,
 116                          ACE_Addr::sap_any,
 117                          0,
 118                          O_CREAT | O_TRUNC | O_WRONLY,
 119                          ACE_DEFAULT_FILE_PERMS) == -1)
 120     ACE_ERROR ((LM_ERROR,
 121                 ACE_TEXT ("Could not open file %p\n"),
 122                 this->file_.get_path_name ()));
 123   else
 124     (*this->request_count_)++;
 125 }
 126
 127 void
 128 Iterator_Handler::deactivate ()
 129 {
 130   // Get the POA used when activating the Reply Handler object.
 131   PortableServer::POA_var poa =
 132     this->_default_POA ();
 133
 134   // Get the object ID associated with this servant.
 135   PortableServer::ObjectId_var oid =
 136     poa->servant_to_id (this);
 137
 138   // Now deactivate the iterator object.
 139   poa->deactivate_object (oid.in ());
 140 }
 141
 142
 143 int
 144 Iterator_Handler::get_viewer (char *viewer,
 145                               size_t length)
 146 {
 147   const char *content_type =
 148     this->metadata_->content_type.in ();
 149
 150   if (ACE_OS::strcasecmp (content_type, "text/html") == 0)
 151     {
 152       const char lynx[] = "lynx";
 153       if (length <= sizeof (lynx))
 154         return -1;
 155       else
 156         ACE_OS::strcpy (viewer, lynx);
 157     }
 158   else if (ACE_OS::strcasecmp (content_type,
 159                                "text/plain") == 0)
 160     {
 161       const char more[] = "more";
 162       if (length <= sizeof (more))
 163         return -1;
 164       else
 165         ACE_OS::strcpy (viewer, more);
 166     }
 167   else if (ACE_OS::strcasecmp (content_type,
 168                                "application/postscript") == 0)
 169     {
 170       const char ghostview[] = "ghostview";
 171       if (length <= sizeof (ghostview))
 172         return -1;
 173       else
 174         ACE_OS::strcpy (viewer, ghostview);
 175     }
 176   else if (ACE_OS::strcasecmp (content_type,
 177                                "application/pdf") == 0)
 178     {
 179       const char acroread[] = "acroread";
 180       if (length <= sizeof (acroread))
 181         return -1;
 182       else
 183         ACE_OS::strcpy (viewer, acroread);
 184     }
 185   else if (ACE_OS::strcasecmp (content_type,
 186                                "image/jpeg") == 0
 187            || ACE_OS::strcasecmp (content_type,
 188                                   "image/gif") == 0
 189            || ACE_OS::strcasecmp (content_type,
 190                                   "image/tiff") == 0
 191            || ACE_OS::strcasecmp (content_type,
 192                                   "image/png") == 0)
 193     {
 194       const char xv[] = "xv";
 195       if (length <= sizeof (xv))
 196         return -1;
 197       else
 198         ACE_OS::strcpy (viewer, xv);
 199     }
 200   else
 201     ACE_ERROR_RETURN ((LM_ERROR,
 202                        ACE_TEXT ("Unsupported MIME type: <%s>\n"),
 203                        content_type),
 204                       -1);
 205
 206   return 0;
 207 }
 208
 209 int
 210 Iterator_Handler::spawn_viewer ()
 211 {
 212   char viewer[BUFSIZ];
 213
 214   if (this->get_viewer (viewer,
 215                         sizeof viewer) != 0)
 216     ACE_ERROR_RETURN ((LM_ERROR,
 217                        ACE_TEXT ("Problem determining which external ")
 218                        ACE_TEXT ("viewer to use.\n")),
 219                       -1);
 220
 221   // Set up the command line that will be used when spawning the
 222   // external viewer.
 223   ACE_Process_Options opts;
 224   opts.command_line (ACE_TEXT ("%s %s"),
 225                      viewer,
 226                      this->file_.get_path_name ());
 227
 228   pid_t result = ACE_Process_Manager::instance ()->spawn (opts);
 229
 230   switch (result)
 231     {
 232     case 0:
 233       // Child
 234       return 0;
 235     case ACE_INVALID_PID:
 236       ACE_ERROR_RETURN ((LM_ERROR,
 237                          ACE_TEXT ("Error during viewer spawn of %p\n"),
 238                          opts.command_line_buf ()),
 239                         -1);
 240     default:
 241       // Parent
 242       ACE_DEBUG ((LM_INFO,
 243                   ACE_TEXT ("Spawned viewer <%s> with PID <%d>.\n"),
 244                   viewer,
 245                   result));
 246       break;
 247     }
 248
 249   return 0;
 250 }