src/libopensrf/osrf_prefork.c

   1 #include <opensrf/osrf_prefork.h>
   2 #include <opensrf/osrf_app_session.h>
   3 #include <opensrf/osrf_application.h>
   4 #include <signal.h>
   5
   6 /* true if we just deleted a child.  This will allow us to make sure we're
   7         not trying to use freed memory */
   8 int child_dead;
   9
  10 int main();
  11 void sigchld_handler( int sig );
  12
  13 int osrf_prefork_run(char* appname) {
  14
  15         if(!appname) {
  16                 osrfLogError( OSRF_LOG_MARK, "osrf_prefork_run requires an appname to run!");
  17                 return -1;
  18         }
  19
  20         set_proc_title( "OpenSRF Listener [%s]", appname );
  21
  22         int maxr = 1000;
  23         int maxc = 10;
  24         int minc = 3;
  25     int kalive = 5;
  26
  27         osrfLogInfo( OSRF_LOG_MARK, "Loading config in osrf_forker for app %s", appname);
  28
  29         char* max_req = osrf_settings_host_value("/apps/%s/unix_config/max_requests", appname);
  30         char* min_children = osrf_settings_host_value("/apps/%s/unix_config/min_children", appname);
  31         char* max_children = osrf_settings_host_value("/apps/%s/unix_config/max_children", appname);
  32         char* keepalive = osrf_settings_host_value("/apps/%s/keepalive", appname);
  33
  34         if(!keepalive) osrfLogWarning( OSRF_LOG_MARK, "Keepalive is not defined, assuming %d", kalive);
  35         else kalive = atoi(keepalive);
  36
  37         if(!max_req) osrfLogWarning( OSRF_LOG_MARK, "Max requests not defined, assuming %d", maxr);
  38         else maxr = atoi(max_req);
  39
  40         if(!min_children) osrfLogWarning( OSRF_LOG_MARK, "Min children not defined, assuming %d", minc);
  41         else minc = atoi(min_children);
  42
  43         if(!max_children) osrfLogWarning( OSRF_LOG_MARK, "Max children not defined, assuming %d", maxc);
  44         else maxc = atoi(max_children);
  45
  46     free(keepalive);
  47         free(max_req);
  48         free(min_children);
  49         free(max_children);
  50         /* --------------------------------------------------- */
  51
  52         char* resc = va_list_to_string("%s_listener", appname);
  53
  54         if(!osrfSystemBootstrapClientResc( NULL, NULL, resc )) {
  55                 osrfLogError( OSRF_LOG_MARK, "Unable to bootstrap client for osrf_prefork_run()");
  56                 free(resc);
  57                 return -1;
  58         }
  59
  60         free(resc);
  61
  62         prefork_simple* forker = prefork_simple_init(
  63                 osrfSystemGetTransportClient(), maxr, minc, maxc);
  64
  65         if(forker == NULL) {
  66                 osrfLogError( OSRF_LOG_MARK, "osrf_prefork_run() failed to create prefork_simple object");
  67                 return -1;
  68         }
  69
  70         forker->appname = strdup(appname);
  71         forker->keepalive       = kalive;
  72
  73         prefork_launch_children(forker);
  74
  75         osrf_prefork_register_routers(appname);
  76
  77         osrfLogInfo( OSRF_LOG_MARK, "Launching osrf_forker for app %s", appname);
  78         prefork_run(forker);
  79
  80         osrfLogWarning( OSRF_LOG_MARK, "prefork_run() retuned - how??");
  81         prefork_free(forker);
  82         return 0;
  83
  84 }
  85
  86 void osrf_prefork_register_routers( char* appname ) {
  87
  88         osrfStringArray* arr = osrfNewStringArray(4);
  89
  90         int c = osrfConfigGetValueList( NULL, arr, "/routers/router" );
  91         char* routerName = osrfConfigGetValue( NULL, "/router_name" );
  92         transport_client* client = osrfSystemGetTransportClient();
  93
  94         osrfLogInfo( OSRF_LOG_MARK, "router name is %s and we have %d routers to connect to", routerName, c );
  95
  96         while( c ) {
  97                 char* domain = osrfStringArrayGetString(arr, --c);
  98                 if(domain) {
  99
 100                         char* jid = va_list_to_string( "%s@%s/router", routerName, domain );
 101                         osrfLogInfo( OSRF_LOG_MARK, "Registering with router %s", jid );
 102
 103                         transport_message* msg = message_init("registering", NULL, NULL, jid, NULL );
 104                         message_set_router_info( msg, NULL, NULL, appname, "register", 0 );
 105
 106                         client_send_message( client, msg );
 107                         message_free( msg );
 108                         free(jid);
 109                 }
 110         }
 111
 112         free(routerName);
 113         osrfStringArrayFree(arr);
 114 }
 115
 116 int prefork_child_init_hook(prefork_child* child) {
 117
 118         if(!child) return -1;
 119         osrfLogDebug( OSRF_LOG_MARK, "Child init hook for child %d", child->pid);
 120         char* resc = va_list_to_string("%s_drone",child->appname);
 121
 122    /* if we're a source-client, tell the logger now that we're a new process*/
 123    char* isclient = osrfConfigGetValue(NULL, "/client");
 124    if( isclient && !strcasecmp(isclient,"true") )
 125       osrfLogSetIsClient(1);
 126    free(isclient);
 127
 128
 129         /* we want to remove traces of our parents socket connection
 130          * so we can have our own */
 131         osrfSystemIgnoreTransportClient();
 132
 133         if(!osrfSystemBootstrapClientResc( NULL, NULL, resc)) {
 134                 osrfLogError( OSRF_LOG_MARK, "Unable to bootstrap client for osrf_prefork_run()");
 135                 free(resc);
 136                 return -1;
 137         }
 138
 139         free(resc);
 140
 141         if( ! osrfAppRunChildInit(child->appname) ) {
 142                 osrfLogDebug(OSRF_LOG_MARK, "Prefork child_init succeeded\n");
 143         } else {
 144                 osrfLogError(OSRF_LOG_MARK, "Prefork child_init failed\n");
 145                 return -1;
 146         }
 147
 148         set_proc_title( "OpenSRF Drone [%s]", child->appname );
 149         return 0;
 150 }
 151
 152 void prefork_child_process_request(prefork_child* child, char* data) {
 153         if( !child ) return;
 154
 155         transport_client* client = osrfSystemGetTransportClient();
 156
 157         if(!client_connected(client)) {
 158                 osrfSystemIgnoreTransportClient();
 159                 osrfLogWarning(OSRF_LOG_MARK, "Reconnecting child to opensrf after disconnect...");
 160                 if(!osrf_system_bootstrap_client(NULL, NULL)) {
 161                         osrfLogError( OSRF_LOG_MARK,
 162                                 "Unable to bootstrap client in prefork_child_process_request()");
 163                         sleep(1);
 164          osrf_prefork_child_exit(child);
 165                 }
 166         }
 167
 168         /* construct the message from the xml */
 169         transport_message* msg = new_message_from_xml( data );
 170
 171         osrfAppSession* session = osrf_stack_transport_handler(msg, child->appname);
 172         if(!session) return;
 173
 174         if( session->stateless && session->state != OSRF_SESSION_CONNECTED ) {
 175                 osrfAppSessionFree( session );
 176                 return;
 177         }
 178
 179         osrfLogDebug( OSRF_LOG_MARK, "Entering keepalive loop for session %s", session->session_id );
 180         int keepalive = child->keepalive;
 181         int retval;
 182         int recvd;
 183         time_t start;
 184         time_t end;
 185
 186         while(1) {
 187
 188                 osrfLogDebug(OSRF_LOG_MARK,
 189                                 "osrf_prefork calling queue_wait [%d] in keepalive loop", keepalive);
 190                 start           = time(NULL);
 191                 retval  = osrf_app_session_queue_wait(session, keepalive, &recvd);
 192                 end             = time(NULL);
 193
 194                 osrfLogDebug(OSRF_LOG_MARK, "Data received == %d", recvd);
 195
 196                 if(retval) {
 197                         osrfLogError(OSRF_LOG_MARK, "queue-wait returned non-success %d", retval);
 198                         break;
 199                 }
 200
 201                 /* see if the client disconnected from us */
 202                 if(session->state != OSRF_SESSION_CONNECTED) break;
 203
 204                 /* if no data was reveived within the timeout interval */
 205                 if( !recvd && (end - start) >= keepalive ) {
 206                         osrfLogInfo(OSRF_LOG_MARK, "No request was received in %d seconds, exiting stateful session", keepalive);
 207                         osrfAppSessionStatus(
 208                                         session,
 209                                         OSRF_STATUS_TIMEOUT,
 210                                         "osrfConnectStatus",
 211                                         0, "Disconnected on timeout" );
 212
 213                         break;
 214                 }
 215         }
 216
 217         osrfLogDebug( OSRF_LOG_MARK, "Exiting keepalive loop for session %s", session->session_id );
 218         osrfAppSessionFree( session );
 219         return;
 220 }
 221
 222
 223 prefork_simple*  prefork_simple_init( transport_client* client,
 224                 int max_requests, int min_children, int max_children ) {
 225
 226         if( min_children > max_children ) {
 227                 osrfLogError( OSRF_LOG_MARK,  "min_children (%d) is greater "
 228                                 "than max_children (%d)", min_children, max_children );
 229                 return NULL;
 230         }
 231
 232         if( max_children > ABS_MAX_CHILDREN ) {
 233                 osrfLogError( OSRF_LOG_MARK,  "max_children (%d) is greater than ABS_MAX_CHILDREN (%d)",
 234                                 max_children, ABS_MAX_CHILDREN );
 235                 return NULL;
 236         }
 237
 238         osrfLogInfo(OSRF_LOG_MARK, "Prefork launching child with max_request=%d,"
 239                 "min_children=%d, max_children=%d", max_requests, min_children, max_children );
 240
 241         /* flesh out the struct */
 242         prefork_simple* prefork = (prefork_simple*) safe_malloc(sizeof(prefork_simple));
 243         prefork->max_requests = max_requests;
 244         prefork->min_children = min_children;
 245         prefork->max_children = max_children;
 246         prefork->first_child = NULL;
 247         prefork->connection = client;
 248
 249         return prefork;
 250 }
 251
 252 prefork_child*  launch_child( prefork_simple* forker ) {
 253
 254         pid_t pid;
 255         int data_fd[2];
 256         int status_fd[2];
 257
 258         /* Set up the data pipes and add the child struct to the parent */
 259         if( pipe(data_fd) < 0 ) { /* build the data pipe*/
 260                 osrfLogError( OSRF_LOG_MARK,  "Pipe making error" );
 261                 return NULL;
 262         }
 263
 264         if( pipe(status_fd) < 0 ) {/* build the status pipe */
 265                 osrfLogError( OSRF_LOG_MARK,  "Pipe making error" );
 266                 return NULL;
 267         }
 268
 269         osrfLogInternal( OSRF_LOG_MARK,  "Pipes: %d %d %d %d", data_fd[0], data_fd[1], status_fd[0], status_fd[1] );
 270         prefork_child* child = prefork_child_init( forker->max_requests, data_fd[0],
 271                         data_fd[1], status_fd[0], status_fd[1] );
 272
 273         child->appname = strdup(forker->appname);
 274         child->keepalive = forker->keepalive;
 275
 276
 277         add_prefork_child( forker, child );
 278
 279         if( (pid=fork()) < 0 ) {
 280                 osrfLogError( OSRF_LOG_MARK,  "Forking Error" );
 281                 return NULL;
 282         }
 283
 284         if( pid > 0 ) {  /* parent */
 285
 286                 signal(SIGCHLD, sigchld_handler);
 287                 (forker->current_num_children)++;
 288                 child->pid = pid;
 289
 290                 osrfLogDebug( OSRF_LOG_MARK,  "Parent launched %d", pid );
 291                 /* *no* child pipe FD's can be closed or the parent will re-use fd's that
 292                         the children are currently using */
 293                 return child;
 294         }
 295
 296         else { /* child */
 297
 298                 osrfLogInternal( OSRF_LOG_MARK, "I am  new child with read_data_fd = %d and write_status_fd = %d",
 299                         child->read_data_fd, child->write_status_fd );
 300
 301                 child->pid = getpid();
 302                 close( child->write_data_fd );
 303                 close( child->read_status_fd );
 304
 305                 /* do the initing */
 306                 if( prefork_child_init_hook(child) == -1 ) {
 307                         osrfLogError(OSRF_LOG_MARK,
 308                                 "Forker child going away because we could not connect to OpenSRF...");
 309          osrf_prefork_child_exit(child);
 310                 }
 311
 312                 prefork_child_wait( child );
 313       osrf_prefork_child_exit(child); /* just to be sure */
 314          }
 315         return NULL;
 316 }
 317
 318 void osrf_prefork_child_exit(prefork_child* child) {
 319    osrfAppRunExitCode();
 320    exit(0);
 321 }
 322
 323 void prefork_launch_children( prefork_simple* forker ) {
 324         if(!forker) return;
 325         int c = 0;
 326         while( c++ < forker->min_children )
 327                 launch_child( forker );
 328 }
 329
 330
 331 void sigchld_handler( int sig ) {
 332         signal(SIGCHLD, sigchld_handler);
 333         child_dead = 1;
 334 }
 335
 336
 337 void reap_children( prefork_simple* forker ) {
 338
 339         pid_t child_pid;
 340         int status;
 341
 342         while( (child_pid=waitpid(-1,&status,WNOHANG)) > 0)
 343                 del_prefork_child( forker, child_pid );
 344
 345         /* replenish */
 346         while( forker->current_num_children < forker->min_children )
 347                 launch_child( forker );
 348
 349         child_dead = 0;
 350 }
 351
 352 void prefork_run(prefork_simple* forker) {
 353
 354         if( forker->first_child == NULL )
 355                 return;
 356
 357         transport_message* cur_msg = NULL;
 358
 359
 360         while(1) {
 361
 362                 if( forker->first_child == NULL ) {/* no more children */
 363                         osrfLogWarning( OSRF_LOG_MARK, "No more children..." );
 364                         return;
 365                 }
 366
 367                 osrfLogDebug( OSRF_LOG_MARK, "Forker going into wait for data...");
 368                 cur_msg = client_recv( forker->connection, -1 );
 369
 370                 //fprintf(stderr, "Got Data %f\n", get_timestamp_millis() );
 371
 372                 if( cur_msg == NULL ) continue;
 373
 374                 int honored = 0;        /* true if we've serviced the request */
 375                 int no_recheck = 0;
 376
 377                 while( ! honored ) {
 378
 379                         if(!no_recheck) check_children( forker, 0 );
 380                         no_recheck = 0;
 381
 382                         osrfLogDebug( OSRF_LOG_MARK,  "Server received inbound data" );
 383                         int k;
 384                         prefork_child* cur_child = forker->first_child;
 385
 386                         /* Look for an available child */
 387                         for( k = 0; k < forker->current_num_children; k++ ) {
 388
 389                                 osrfLogInternal( OSRF_LOG_MARK, "Searching for available child. cur_child->pid = %d", cur_child->pid );
 390                                 osrfLogInternal( OSRF_LOG_MARK, "Current num children %d and loop %d", forker->current_num_children, k);
 391
 392                                 if( cur_child->available ) {
 393                                         osrfLogDebug( OSRF_LOG_MARK,  "forker sending data to %d", cur_child->pid );
 394
 395                                         message_prepare_xml( cur_msg );
 396                                         char* data = cur_msg->msg_xml;
 397                                         if( ! data || strlen(data) < 1 ) break;
 398
 399                                         cur_child->available = 0;
 400                                         osrfLogInternal( OSRF_LOG_MARK,  "Writing to child fd %d", cur_child->write_data_fd );
 401
 402                                         int written = 0;
 403                                         //fprintf(stderr, "Writing Data %f\n", get_timestamp_millis() );
 404                                         if( (written = write( cur_child->write_data_fd, data, strlen(data) + 1 )) < 0 ) {
 405                                                 osrfLogWarning( OSRF_LOG_MARK, "Write returned error %d", errno);
 406                                                 cur_child = cur_child->next;
 407                                                 continue;
 408                                         }
 409
 410                                         //fprintf(stderr, "Wrote %d bytes to child\n", written);
 411
 412                                         forker->first_child = cur_child->next;
 413                                         honored = 1;
 414                                         break;
 415                                 } else
 416                                         cur_child = cur_child->next;
 417                         }
 418
 419                         /* if none available, add a new child if we can */
 420                         if( ! honored ) {
 421                                 osrfLogDebug( OSRF_LOG_MARK, "Not enough children, attempting to add...");
 422
 423                                 if( forker->current_num_children < forker->max_children ) {
 424                                         osrfLogDebug( OSRF_LOG_MARK,  "Launching new child with current_num = %d",
 425                                                         forker->current_num_children );
 426
 427                                         prefork_child* new_child = launch_child( forker );
 428                     if( new_child ) {
 429
 430                                             message_prepare_xml( cur_msg );
 431                                             char* data = cur_msg->msg_xml;
 432
 433                         if( data ) {
 434                             int len = strlen(data);
 435
 436                             if( len > 0 ) {
 437                                                     new_child->available = 0;
 438                                                     osrfLogDebug( OSRF_LOG_MARK,  "Writing to new child fd %d : pid %d",
 439                                                                 new_child->write_data_fd, new_child->pid );
 440
 441                                                     if( write( new_child->write_data_fd, data, len + 1 ) >= 0 ) {
 442                                                         forker->first_child = new_child->next;
 443                                                         honored = 1;
 444                                 }
 445                             }
 446                         }
 447                     }
 448
 449                                 }
 450                         }
 451
 452                         if( !honored ) {
 453                                 osrfLogWarning( OSRF_LOG_MARK,  "No children available, waiting...");
 454
 455                                 check_children( forker, 1 );  /* non-poll version */
 456                                 /* tell the loop no to call check_children again, since we're calling it now */
 457                                 no_recheck = 1;
 458                         }
 459
 460                         if( child_dead )
 461                                 reap_children(forker);
 462
 463
 464                         //fprintf(stderr, "Parent done with request %f\n", get_timestamp_millis() );
 465
 466                 } // honored?
 467
 468                 message_free( cur_msg );
 469
 470         } /* top level listen loop */
 471
 472 }
 473
 474
 475 /** XXX Add a flag which tells select() to wait forever on children
 476  * in the best case, this will be faster than calling usleep(x), and
 477  * in the worst case it won't be slower and will do less logging...
 478  */
 479
 480 void check_children( prefork_simple* forker, int forever ) {
 481
 482         //check_begin:
 483
 484         int select_ret;
 485         fd_set read_set;
 486         FD_ZERO(&read_set);
 487         int max_fd = 0;
 488         int n;
 489
 490
 491         if( child_dead )
 492                 reap_children(forker);
 493
 494         prefork_child* cur_child = forker->first_child;
 495
 496         int i;
 497         for( i = 0; i!= forker->current_num_children; i++ ) {
 498
 499                 if( cur_child->read_status_fd > max_fd )
 500                         max_fd = cur_child->read_status_fd;
 501                 FD_SET( cur_child->read_status_fd, &read_set );
 502                 cur_child = cur_child->next;
 503         }
 504
 505         FD_CLR(0,&read_set);/* just to be sure */
 506
 507         if( forever ) {
 508                 osrfLogWarning(OSRF_LOG_MARK, "We have no children available - waiting for one to show up...");
 509
 510                 if( (select_ret=select( max_fd + 1 , &read_set, NULL, NULL, NULL)) == -1 ) {
 511                         osrfLogWarning( OSRF_LOG_MARK,  "Select returned error %d on check_children", errno );
 512                 }
 513                 osrfLogInfo(OSRF_LOG_MARK, "select() completed after waiting on children to become available");
 514
 515         } else {
 516
 517                 struct timeval tv;
 518                 tv.tv_sec       = 0;
 519                 tv.tv_usec      = 0;
 520
 521                 if( (select_ret=select( max_fd + 1 , &read_set, NULL, NULL, &tv)) == -1 ) {
 522                         osrfLogWarning( OSRF_LOG_MARK,  "Select returned error %d on check_children", errno );
 523                 }
 524         }
 525
 526         if( select_ret == 0 )
 527                 return;
 528
 529         /* see if one of a child has told us it's done */
 530         cur_child = forker->first_child;
 531         int j;
 532         int num_handled = 0;
 533         for( j = 0; j!= forker->current_num_children && num_handled < select_ret ; j++ ) {
 534
 535                 if( FD_ISSET( cur_child->read_status_fd, &read_set ) ) {
 536                         //printf( "Server received status from a child %d\n", cur_child->pid );
 537                         osrfLogDebug( OSRF_LOG_MARK,  "Server received status from a child %d", cur_child->pid );
 538
 539                         num_handled++;
 540
 541                         /* now suck off the data */
 542                         char buf[64];
 543                         osrf_clearbuf( buf, sizeof(buf) );
 544                         if( (n=read(cur_child->read_status_fd, buf, 63))  < 0 ) {
 545                                 osrfLogWarning( OSRF_LOG_MARK, "Read error after select in child status read with errno %d", errno);
 546                         }
 547
 548                         osrfLogDebug( OSRF_LOG_MARK,  "Read %d bytes from status buffer: %s", n, buf );
 549                         cur_child->available = 1;
 550                 }
 551                 cur_child = cur_child->next;
 552         }
 553
 554 }
 555
 556
 557 void prefork_child_wait( prefork_child* child ) {
 558
 559         int i,n;
 560         growing_buffer* gbuf = buffer_init( READ_BUFSIZE );
 561         char buf[READ_BUFSIZE];
 562         osrf_clearbuf( buf, sizeof(buf) );
 563
 564         for( i = 0; i < child->max_requests; i++ ) {
 565
 566                 n = -1;
 567                 int gotdata = 0;
 568                 clr_fl(child->read_data_fd, O_NONBLOCK );
 569
 570                 while( (n=read(child->read_data_fd, buf, READ_BUFSIZE-1)) > 0 ) {
 571                         osrfLogDebug(OSRF_LOG_MARK, "Prefork child read %d bytes of data", n);
 572                         if(!gotdata)
 573                                 set_fl(child->read_data_fd, O_NONBLOCK );
 574                         buffer_add( gbuf, buf );
 575                         osrf_clearbuf( buf, sizeof(buf) );
 576                         gotdata = 1;
 577                 }
 578
 579                 if( errno == EAGAIN ) n = 0;
 580
 581       if( errno == EPIPE ) {
 582          osrfLogDebug(OSRF_LOG_MARK, "C child attempted read on broken pipe, exiting...");
 583          break;
 584       }
 585
 586                 if( n < 0 ) {
 587                         osrfLogWarning( OSRF_LOG_MARK,  "Prefork child read returned error with errno %d", errno );
 588                         break;
 589
 590                 } else if( gotdata ) {
 591                         osrfLogDebug(OSRF_LOG_MARK, "Prefork child got a request.. processing..");
 592                         prefork_child_process_request(child, gbuf->buf);
 593                         buffer_reset( gbuf );
 594                 }
 595
 596                 if( i < child->max_requests - 1 )
 597                         write( child->write_status_fd, "available" /*less than 64 bytes*/, 9 );
 598         }
 599
 600         buffer_free(gbuf);
 601
 602         osrfLogDebug( OSRF_LOG_MARK, "Child with max-requests=%d, num-served=%d exiting...[%ld]",
 603                         child->max_requests, i, (long) getpid() );
 604
 605    osrf_prefork_child_exit(child); /* just to be sure */
 606 }
 607
 608
 609 void add_prefork_child( prefork_simple* forker, prefork_child* child ) {
 610
 611         if( forker->first_child == NULL ) {
 612                 forker->first_child = child;
 613                 child->next = child;
 614                 return;
 615         }
 616
 617         /* we put the child in as the last because, regardless,
 618                 we have to do the DLL splice dance, and this is the
 619            simplest way */
 620
 621         prefork_child* start_child = forker->first_child;
 622         while(1) {
 623                 if( forker->first_child->next == start_child )
 624                         break;
 625                 forker->first_child = forker->first_child->next;
 626         }
 627
 628         /* here we know that forker->first_child is the last element
 629                 in the list and start_child is the first.  Insert the
 630                 new child between them*/
 631
 632         forker->first_child->next = child;
 633         child->next = start_child;
 634         return;
 635 }
 636
 637 prefork_child* find_prefork_child( prefork_simple* forker, pid_t pid ) {
 638
 639         if( forker->first_child == NULL ) { return NULL; }
 640         prefork_child* start_child = forker->first_child;
 641         do {
 642                 if( forker->first_child->pid == pid )
 643                         return forker->first_child;
 644         } while( (forker->first_child = forker->first_child->next) != start_child );
 645
 646         return NULL;
 647 }
 648
 649
 650 void del_prefork_child( prefork_simple* forker, pid_t pid ) {
 651
 652         if( forker->first_child == NULL ) { return; }
 653
 654         (forker->current_num_children)--;
 655         osrfLogDebug( OSRF_LOG_MARK, "Deleting Child: %d", pid );
 656
 657         prefork_child* start_child = forker->first_child; /* starting point */
 658         prefork_child* cur_child        = start_child; /* current pointer */
 659         prefork_child* prev_child       = start_child; /* the trailing pointer */
 660
 661         /* special case where there is only one in the list */
 662         if( start_child == start_child->next ) {
 663                 if( start_child->pid == pid ) {
 664                         forker->first_child = NULL;
 665
 666                         close( start_child->read_data_fd );
 667                         close( start_child->write_data_fd );
 668                         close( start_child->read_status_fd );
 669                         close( start_child->write_status_fd );
 670
 671                         prefork_child_free( start_child );
 672                 }
 673                 return;
 674         }
 675
 676
 677         /* special case where the first item in the list needs to be removed */
 678         if( start_child->pid == pid ) {
 679
 680                 /* find the last one so we can remove the start_child */
 681                 do {
 682                         prev_child = cur_child;
 683                         cur_child = cur_child->next;
 684                 }while( cur_child != start_child );
 685
 686                 /* now cur_child == start_child */
 687                 prev_child->next = cur_child->next;
 688                 forker->first_child = prev_child;
 689
 690                 close( cur_child->read_data_fd );
 691                 close( cur_child->write_data_fd );
 692                 close( cur_child->read_status_fd );
 693                 close( cur_child->write_status_fd );
 694
 695                 prefork_child_free( cur_child );
 696                 return;
 697         }
 698
 699         do {
 700                 prev_child = cur_child;
 701                 cur_child = cur_child->next;
 702
 703                 if( cur_child->pid == pid ) {
 704                         prev_child->next = cur_child->next;
 705
 706                         close( cur_child->read_data_fd );
 707                         close( cur_child->write_data_fd );
 708                         close( cur_child->read_status_fd );
 709                         close( cur_child->write_status_fd );
 710
 711                         prefork_child_free( cur_child );
 712                         return;
 713                 }
 714
 715         } while(cur_child != start_child);
 716 }
 717
 718
 719
 720
 721 prefork_child* prefork_child_init(
 722         int max_requests, int read_data_fd, int write_data_fd,
 723         int read_status_fd, int write_status_fd ) {
 724
 725         prefork_child* child = (prefork_child*) safe_malloc(sizeof(prefork_child));
 726         child->max_requests             = max_requests;
 727         child->read_data_fd             = read_data_fd;
 728         child->write_data_fd            = write_data_fd;
 729         child->read_status_fd   = read_status_fd;
 730         child->write_status_fd  = write_status_fd;
 731         child->available                        = 1;
 732
 733         return child;
 734 }
 735
 736
 737 int prefork_free( prefork_simple* prefork ) {
 738
 739         while( prefork->first_child != NULL ) {
 740                 osrfLogInfo( OSRF_LOG_MARK,  "Killing children and sleeping 1 to reap..." );
 741                 kill( 0,        SIGKILL );
 742                 sleep(1);
 743         }
 744
 745         client_free(prefork->connection);
 746         free(prefork->appname);
 747         free( prefork );
 748         return 1;
 749 }
 750
 751 int prefork_child_free( prefork_child* child ) {
 752         free(child->appname);
 753         close(child->read_data_fd);
 754         close(child->write_status_fd);
 755         free( child );
 756         return 1;
 757 }
 758