src/ebb.c

   1 /* The Ebb Web Server
   2  * Copyright (c) 2008 Ry Dahl. This software is released under the MIT
   3  * License. See README file for details.
   4  */
   5 #include <unistd.h>
   6 #include <fcntl.h>
   7 #include <sys/types.h>
   8 #include <arpa/inet.h>
   9 #include <netinet/tcp.h>
  10 #include <sys/un.h>
  11 #include <netdb.h>
  12
  13 #include <stdio.h>
  14 #include <string.h>
  15 #include <stdlib.h>
  16 #include <errno.h>
  17 #include <signal.h>
  18 #include <assert.h>
  19
  20 #include <pthread.h>
  21 #include <glib.h>
  22
  23 #define EV_STANDALONE 1
  24 #include <ev.c>
  25
  26 #include "parser.h"
  27 #include "ebb.h"
  28
  29 #define min(a,b) (a < b ? a : b)
  30 #define ramp(a) (a > 0 ? a : 0)
  31
  32 static int server_socket(const int port);
  33 static int server_socket_unix(const char *path, int access_mask);
  34
  35 void env_add(ebb_client *client, const char *field, int flen, const char *value, int vlen)
  36 {
  37   if(client->env_size >= EBB_MAX_ENV) {
  38     client->parser.overflow_error = TRUE;
  39     return;
  40   }
  41   client->env[client->env_size].type = EBB_FIELD_VALUE_PAIR;
  42   client->env[client->env_size].field = field;
  43   client->env[client->env_size].field_length = flen;
  44   client->env[client->env_size].value = value;
  45   client->env[client->env_size].value_length = vlen;
  46   client->env_size += 1;
  47 }
  48
  49
  50 void env_add_const(ebb_client *client, int type, const char *value, int vlen)
  51 {
  52   if(client->env_size >= EBB_MAX_ENV) {
  53     client->parser.overflow_error = TRUE;
  54     return;
  55   }
  56   client->env[client->env_size].type = type;
  57   client->env[client->env_size].field = NULL;
  58   client->env[client->env_size].field_length = -1;
  59   client->env[client->env_size].value = value;
  60   client->env[client->env_size].value_length = vlen;
  61   client->env_size += 1;
  62 }
  63
  64
  65 void http_field_cb(void *data, const char *field, size_t flen, const char *value, size_t vlen)
  66 {
  67   ebb_client *client = (ebb_client*)(data);
  68   assert(field != NULL);
  69   assert(value != NULL);
  70   env_add(client, field, flen, value, vlen);
  71 }
  72
  73
  74 void request_method_cb(void *data, const char *at, size_t length)
  75 {
  76   ebb_client *client = (ebb_client*)(data);
  77   env_add_const(client, EBB_REQUEST_METHOD, at, length);
  78 }
  79
  80
  81 void request_uri_cb(void *data, const char *at, size_t length)
  82 {
  83   ebb_client *client = (ebb_client*)(data);
  84   env_add_const(client, EBB_REQUEST_URI, at, length);
  85 }
  86
  87
  88 void fragment_cb(void *data, const char *at, size_t length)
  89 {
  90   ebb_client *client = (ebb_client*)(data);
  91   env_add_const(client, EBB_FRAGMENT, at, length);
  92 }
  93
  94
  95 void request_path_cb(void *data, const char *at, size_t length)
  96 {
  97   ebb_client *client = (ebb_client*)(data);
  98   env_add_const(client, EBB_REQUEST_PATH, at, length);
  99 }
 100
 101
 102 void query_string_cb(void *data, const char *at, size_t length)
 103 {
 104   ebb_client *client = (ebb_client*)(data);
 105   env_add_const(client, EBB_QUERY_STRING, at, length);
 106 }
 107
 108
 109 void http_version_cb(void *data, const char *at, size_t length)
 110 {
 111   ebb_client *client = (ebb_client*)(data);
 112   env_add_const(client, EBB_HTTP_VERSION, at, length);
 113 }
 114
 115
 116 void content_length_cb(void *data, const char *at, size_t length)
 117 {
 118   ebb_client *client = (ebb_client*)(data);
 119   env_add_const(client, EBB_CONTENT_LENGTH, at, length);
 120   /* atoi_length - why isn't this in the statndard library? i hate c */
 121   int i, mult;
 122   for(mult=1, i=length-1; i>=0; i--, mult*=10)
 123     client->content_length += (at[i] - '0') * mult;
 124 }
 125
 126
 127 const char* localhost_str = "0.0.0.0";
 128 void dispatch(ebb_client *client)
 129 {
 130   ebb_server *server = client->server;
 131
 132   if(client->open == FALSE)
 133     return;
 134
 135   /* Set the env variables */
 136   if(server->port) {
 137     env_add_const(client, EBB_SERVER_NAME
 138                         , localhost_str
 139                         , 7
 140                         );
 141     env_add_const(client, EBB_SERVER_PORT
 142                         , server->port
 143                         , strlen(server->port)
 144                         );
 145   }
 146   server->request_cb(client, server->request_cb_data);
 147 }
 148
 149
 150 void on_timeout(struct ev_loop *loop, ev_timer *watcher, int revents)
 151 {
 152   ebb_client *client = (ebb_client*)(watcher->data);
 153
 154   assert(client->server->loop == loop);
 155   assert(&(client->timeout_watcher) == watcher);
 156
 157   ebb_client_close(client);
 158 #ifdef DEBUG
 159   g_message("peer timed out");
 160 #endif
 161 }
 162
 163 #define client_finished_parsing http_parser_is_finished(&client->parser)
 164 #define total_request_size (client->content_length + client->parser.nread)
 165
 166 void* read_body_into_file(void *_client)
 167 {
 168   ebb_client *client = (ebb_client*)_client;
 169   static unsigned int id;
 170   FILE *tmpfile;
 171
 172   assert(client->open);
 173   assert(client->server->open);
 174   assert(client->content_length > 0);
 175   assert(client_finished_parsing);
 176
 177   /* set blocking socket */
 178   int flags = fcntl(client->fd, F_GETFL, 0);
 179   assert(0 <= fcntl(client->fd, F_SETFL, flags & ~O_NONBLOCK));
 180
 181   sprintf(client->upload_file_filename, "/tmp/ebb_upload_%010d", id++);
 182   tmpfile = fopen(client->upload_file_filename, "w+");
 183   if(tmpfile == NULL) g_message("Cannot open tmpfile %s", client->upload_file_filename);
 184   client->upload_file = tmpfile;
 185
 186   size_t body_head_length = client->read - client->parser.nread;
 187   size_t written = 0, r;
 188   while(written < body_head_length) {
 189     r = fwrite( client->request_buffer + sizeof(char)*(client->parser.nread + written)
 190               , sizeof(char)
 191               , body_head_length - written
 192               , tmpfile
 193               );
 194     if(r <= 0) {
 195       ebb_client_close(client);
 196       return NULL;
 197     }
 198     written += r;
 199   }
 200
 201   int bufsize = 5*1024;
 202   char buffer[bufsize];
 203   size_t received;
 204   while(written < client->content_length) {
 205     received = recv(client->fd
 206                    , buffer
 207                    , min(client->content_length - written, bufsize)
 208                    , 0
 209                    );
 210     if(received < 0) goto error;
 211     client->read += received;
 212
 213     ssize_t w = 0;
 214     int rv;
 215     while(w < received) {
 216       rv = fwrite( buffer + w*sizeof(char)
 217                  , sizeof(char)
 218                  , received - w
 219                  , tmpfile
 220                  );
 221       if(rv <= 0) goto error;
 222       w += rv;
 223     }
 224     written += received;
 225   }
 226   rewind(tmpfile);
 227   // g_debug("%d bytes written to file %s", written, client->upload_file_filename);
 228   dispatch(client);
 229   return NULL;
 230 error:
 231   ebb_client_close(client);
 232   return NULL;
 233 }
 234
 235
 236 void on_readable(struct ev_loop *loop, ev_io *watcher, int revents)
 237 {
 238   ebb_client *client = (ebb_client*)(watcher->data);
 239
 240   assert(client->open);
 241   assert(client->server->open);
 242   assert(client->server->loop == loop);
 243   assert(&client->read_watcher == watcher);
 244
 245   ssize_t read = recv( client->fd
 246                      , client->request_buffer + client->read
 247                      , EBB_BUFFERSIZE - client->read
 248                      , 0
 249                      );
 250   if(read < 0) goto error; /* XXX is this the right action to take for read==0 ? */
 251   if(read == 0) return;
 252   client->read += read;
 253   ev_timer_again(loop, &client->timeout_watcher);
 254
 255   if(client->read == EBB_BUFFERSIZE) goto error;
 256
 257   if(FALSE == client_finished_parsing) {
 258     http_parser_execute( &client->parser
 259                        , client->request_buffer
 260                        , client->read
 261                        , client->parser.nread
 262                        );
 263     if(http_parser_has_error(&client->parser)) goto error;
 264   }
 265
 266   if(client_finished_parsing) {
 267     if(total_request_size == client->read) {
 268       ev_io_stop(loop, watcher);
 269       client->nread_from_body = 0;
 270       dispatch(client);
 271       return;
 272     }
 273     if(total_request_size > EBB_BUFFERSIZE ) {
 274       /* read body into file - in a thread */
 275       ev_io_stop(loop, watcher);
 276       pthread_t thread;
 277       assert(0 <= pthread_create(&thread, NULL, read_body_into_file, client));
 278       pthread_detach(thread);
 279       return;
 280     }
 281   }
 282   return;
 283 error:
 284   if(read < 0) g_message("Error recving data: %s", strerror(errno));
 285   ebb_client_close(client);
 286 }
 287
 288
 289 void on_request(struct ev_loop *loop, ev_io *watcher, int revents)
 290 {
 291   ebb_server *server = (ebb_server*)(watcher->data);
 292   assert(server->open);
 293   assert(server->loop == loop);
 294   assert(&server->request_watcher == watcher);
 295
 296   if(EV_ERROR & revents) {
 297     g_message("on_request() got error event, closing server.");
 298     ebb_server_unlisten(server);
 299     return;
 300   }
 301   /* Now we're going to initialize the client
 302    * and set up her callbacks for read and write
 303    * the client won't get passed back to the user, however,
 304    * until the request is complete and parsed.
 305    */
 306   int i;
 307   ebb_client *client;
 308   /* Get next availible peer */
 309   for(i=0; i < EBB_MAX_CLIENTS; i++)
 310     if(!server->clients[i].open) {
 311       client = &(server->clients[i]);
 312       break;
 313     }
 314   if(client == NULL) {
 315     g_message("Too many peers. Refusing connections.");
 316     return;
 317   }
 318
 319 #ifdef DEBUG
 320   int count = 0;
 321   for(i = 0; i < EBB_MAX_CLIENTS; i++)
 322     if(server->clients[i].open) count += 1;
 323   g_debug("%d open connections", count);
 324
 325   /* does ragel fuck up if request buffer isn't null? */
 326   for(i=0; i< EBB_BUFFERSIZE; i++)
 327     client->request_buffer[i] = 'A';
 328 #endif
 329
 330   client->open = TRUE;
 331   client->server = server;
 332
 333   /* DO SOCKET STUFF */
 334   socklen_t len;
 335   client->fd = accept(server->fd, (struct sockaddr*)&(server->sockaddr), &len);
 336   assert(client->fd >= 0);
 337   int flags = fcntl(client->fd, F_GETFL, 0);
 338   assert(0 <= fcntl(client->fd, F_SETFL, flags | O_NONBLOCK));
 339
 340   /* INITIALIZE http_parser */
 341   http_parser_init(&(client->parser));
 342   client->parser.data = client;
 343   client->parser.http_field     = http_field_cb;
 344   client->parser.request_method = request_method_cb;
 345   client->parser.request_uri    = request_uri_cb;
 346   client->parser.fragment       = fragment_cb;
 347   client->parser.request_path   = request_path_cb;
 348   client->parser.query_string   = query_string_cb;
 349   client->parser.http_version   = http_version_cb;
 350   client->parser.content_length = content_length_cb;
 351
 352   /* OTHER */
 353
 354   client->env_size = 0;
 355   client->read = client->nread_from_body = 0;
 356   client->response_buffer->len = 0; /* see note in ebb_client_close */
 357   client->content_length = 0;
 358
 359   client->status_sent = FALSE;
 360   client->headers_sent = FALSE;
 361   client->body_sent = FALSE;
 362
 363   /* SETUP READ AND TIMEOUT WATCHERS */
 364   client->read_watcher.data = client;
 365   ev_init(&client->read_watcher, on_readable);
 366   ev_io_set(&client->read_watcher, client->fd, EV_READ | EV_ERROR);
 367   ev_io_start(server->loop, &client->read_watcher);
 368
 369   client->timeout_watcher.data = client;
 370   ev_timer_init(&client->timeout_watcher, on_timeout, EBB_TIMEOUT, EBB_TIMEOUT);
 371   ev_timer_start(server->loop, &client->timeout_watcher);
 372 }
 373
 374
 375 ebb_server* ebb_server_alloc()
 376 {
 377   ebb_server *server = g_new0(ebb_server, 1);
 378   return server;
 379 }
 380
 381
 382 void ebb_server_init( ebb_server *server
 383                     , struct ev_loop *loop
 384                     , ebb_request_cb request_cb
 385                     , void *request_cb_data
 386                     )
 387 {
 388   int i;
 389   for(i=0; i < EBB_MAX_CLIENTS; i++)
 390     server->clients[i].response_buffer = g_string_new("");
 391
 392   server->request_cb = request_cb;
 393   server->request_cb_data = request_cb_data;
 394   server->loop = loop;
 395   server->open = FALSE;
 396   server->fd = -1;
 397   return;
 398 error:
 399   ebb_server_free(server);
 400   return;
 401 }
 402
 403
 404 void ebb_server_free(ebb_server *server)
 405 {
 406   ebb_server_unlisten(server);
 407
 408   int i;
 409   for(i=0; i < EBB_MAX_CLIENTS; i++)
 410     g_string_free(server->clients[i].response_buffer, TRUE);
 411   if(server->port)
 412     free(server->port);
 413   if(server->socketpath)
 414     free(server->socketpath);
 415   free(server);
 416 }
 417
 418
 419 void ebb_server_unlisten(ebb_server *server)
 420 {
 421   if(server->open) {
 422     int i;
 423     ebb_client *client;
 424     ev_io_stop(server->loop, &server->request_watcher);
 425     close(server->fd);
 426     if(server->socketpath)
 427       unlink(server->socketpath);
 428     server->open = FALSE;
 429   }
 430 }
 431
 432
 433 void ebb_server_listen(ebb_server *server)
 434 {
 435   int r = listen(server->fd, EBB_MAX_CLIENTS);
 436   assert(r >= 0);
 437   assert(server->open == FALSE);
 438   server->open = TRUE;
 439
 440   server->request_watcher.data = server;
 441   ev_init (&server->request_watcher, on_request);
 442   ev_io_set (&server->request_watcher, server->fd, EV_READ | EV_ERROR);
 443   ev_io_start (server->loop, &server->request_watcher);
 444 }
 445
 446
 447 int ebb_server_listen_on_port(ebb_server *server, const int port)
 448 {
 449   int sfd = -1;
 450   struct linger ling = {0, 0};
 451   struct sockaddr_in addr;
 452   int flags = 1;
 453
 454   if ((sfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
 455     perror("socket()");
 456     goto error;
 457   }
 458
 459   flags = fcntl(sfd, F_GETFL, 0);
 460   if(fcntl(sfd, F_SETFL, flags | O_NONBLOCK) < 0) {
 461     perror("setting O_NONBLOCK");
 462     goto error;
 463   }
 464
 465   flags = 1;
 466   setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, (void *)&flags, sizeof(flags));
 467   setsockopt(sfd, SOL_SOCKET, SO_KEEPALIVE, (void *)&flags, sizeof(flags));
 468   setsockopt(sfd, SOL_SOCKET, SO_LINGER, (void *)&ling, sizeof(ling));
 469   setsockopt(sfd, IPPROTO_TCP, TCP_NODELAY, (void *)&flags, sizeof(flags));
 470
 471   /*
 472    * the memset call clears nonstandard fields in some impementations
 473    * that otherwise mess things up.
 474    */
 475   memset(&addr, 0, sizeof(addr));
 476
 477   addr.sin_family = AF_INET;
 478   addr.sin_port = htons(port);
 479   addr.sin_addr.s_addr = htonl(INADDR_ANY);
 480
 481   if (bind(sfd, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
 482     perror("bind()");
 483     goto error;
 484   }
 485   if (listen(sfd, EBB_MAX_CLIENTS) < 0) {
 486     perror("listen()");
 487     goto error;
 488   }
 489   server->fd = sfd;
 490   server->port = malloc(sizeof(char)*8); /* for easy access to the port */
 491   sprintf(server->port, "%d", port);
 492   ebb_server_listen(server);
 493   return server->fd;
 494 error:
 495   if(sfd > 0) close(sfd);
 496   return -1;
 497 }
 498
 499
 500 int ebb_server_listen_on_socket(ebb_server *server, const char *socketpath)
 501 {
 502   int fd = server_socket_unix(socketpath, 0755);
 503   if(fd < 0) return 0;
 504   server->socketpath = strdup(socketpath);
 505   server->fd = fd;
 506   ebb_server_listen(server);
 507   return fd;
 508 }
 509
 510
 511 void ebb_client_close(ebb_client *client)
 512 {
 513   if(client->open) {
 514     ev_io_stop(client->server->loop, &client->read_watcher);
 515     ev_io_stop(client->server->loop, &client->write_watcher);
 516     ev_timer_stop(client->server->loop, &client->timeout_watcher);
 517
 518     if(client->upload_file) {
 519       fclose(client->upload_file);
 520       unlink(client->upload_file_filename);
 521     }
 522
 523     /* here we do not free the already allocated GString client->response_buffer
 524      * that we're holding the response in. we reuse it again -
 525      * presumably because the backend is going to keep sending such long
 526      * requests.
 527      */
 528     client->response_buffer->len = 0;
 529
 530     close(client->fd);
 531     client->open = FALSE;
 532   }
 533 }
 534
 535
 536 void on_client_writable(struct ev_loop *loop, ev_io *watcher, int revents)
 537 {
 538   ebb_client *client = (ebb_client*)(watcher->data);
 539   ssize_t sent;
 540
 541   if(EV_ERROR & revents) {
 542     g_message("on_client_writable() got error event, closing peer");
 543     return;
 544   }
 545
 546   //if(client->written != 0)
 547   //  g_debug("total written: %d", (int)(client->written));
 548
 549   sent = send( client->fd
 550              , client->response_buffer->str + sizeof(gchar)*(client->written)
 551              , client->response_buffer->len - client->written
 552              , 0
 553              );
 554   if(sent < 0) {
 555 #ifdef DEBUG
 556     g_message("Error writing: %s", strerror(errno));
 557 #endif
 558     ebb_client_close(client);
 559     return;
 560   }
 561   client->written += sent;
 562
 563   assert(client->written <= client->response_buffer->len);
 564   //g_message("wrote %d bytes. total: %d", (int)sent, (int)(client->written));
 565
 566   ev_timer_again(loop, &(client->timeout_watcher));
 567
 568   if(client->written == client->response_buffer->len)
 569     ebb_client_close(client);
 570 }
 571
 572 void ebb_client_write_status(ebb_client *client, int status, const char *human_status)
 573 {
 574   assert(client->status_sent == FALSE);
 575   g_string_append_printf( client->response_buffer
 576                         , "HTTP/1.1 %d %s\r\n"
 577                         , status
 578                         , human_status
 579                         );
 580   client->status_sent = TRUE;
 581 }
 582
 583 void ebb_client_write_header(ebb_client *client, const char *field, const char *value)
 584 {
 585   assert(client->status_sent == TRUE);
 586   assert(client->headers_sent == FALSE);
 587   g_string_append_printf( client->response_buffer
 588                         , "%s: %s\r\n"
 589                         , field
 590                         , value
 591                         );
 592 }
 593
 594 void ebb_client_write(ebb_client *client, const char *data, int length)
 595 {
 596   g_string_append_len(client->response_buffer, data, length);
 597 }
 598
 599
 600 void ebb_client_finished(ebb_client *client)
 601 {
 602   assert(client->open);
 603   assert(FALSE == ev_is_active(&(client->write_watcher)));
 604
 605   /* assure the socket is still in non-blocking mode
 606    * in the ruby binding, for example, i change this flag
 607    */
 608   int flags = fcntl(client->fd, F_GETFL, 0);
 609   if(0 > fcntl(client->fd, F_SETFL, flags | O_NONBLOCK)) {
 610     perror("fcntl()");
 611     ebb_client_close(client);
 612     return;
 613   }
 614
 615   client->written = 0;
 616   client->write_watcher.data = client;
 617   ev_init (&(client->write_watcher), on_client_writable);
 618   ev_io_set (&(client->write_watcher), client->fd, EV_WRITE | EV_ERROR);
 619   ev_io_start(client->server->loop, &(client->write_watcher));
 620 }
 621
 622
 623 /* pass an allocated buffer and the length to read. this function will try to
 624  * fill the buffer with that length of data read from the body of the request.
 625  * the return value says how much was actually written.
 626  */
 627 int ebb_client_read(ebb_client *client, char *buffer, int length)
 628 {
 629   size_t read;
 630
 631   assert(client->open);
 632   assert(client_finished_parsing);
 633
 634   if(client->upload_file) {
 635     read = fread(buffer, 1, length, client->upload_file);
 636     /* TODO error checking! */
 637     return read;
 638   } else {
 639     char* request_body = client->request_buffer + client->parser.nread;
 640
 641     read = ramp(min(length, client->content_length - client->nread_from_body));
 642     memcpy( buffer
 643           , request_body + client->nread_from_body
 644           , read
 645           );
 646     client->nread_from_body += read;
 647     return read;
 648   }
 649 }
 650
 651 /* The following socket creation routines are modified and stolen from memcached */
 652
 653
 654 static int server_socket_unix(const char *path, int access_mask) {
 655     int sfd;
 656     struct linger ling = {0, 0};
 657     struct sockaddr_un addr;
 658     struct stat tstat;
 659     int flags =1;
 660     int old_umask;
 661
 662     if (!path) {
 663         return -1;
 664     }
 665
 666     if ((sfd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
 667         perror("socket()");
 668         return -1;
 669     }
 670
 671     if ((flags = fcntl(sfd, F_GETFL, 0)) < 0 ||
 672         fcntl(sfd, F_SETFL, flags | O_NONBLOCK) < 0) {
 673         perror("setting O_NONBLOCK");
 674         close(sfd);
 675         return -1;
 676     }
 677
 678     /*
 679      * Clean up a previous socket file if we left it around
 680      */
 681     if (lstat(path, &tstat) == 0) {
 682         if (S_ISSOCK(tstat.st_mode))
 683             unlink(path);
 684     }
 685
 686     flags = 1;
 687     setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, (void *)&flags, sizeof(flags));
 688     setsockopt(sfd, SOL_SOCKET, SO_KEEPALIVE, (void *)&flags, sizeof(flags));
 689     setsockopt(sfd, SOL_SOCKET, SO_LINGER, (void *)&ling, sizeof(ling));
 690
 691     /*
 692      * the memset call clears nonstandard fields in some impementations
 693      * that otherwise mess things up.
 694      */
 695     memset(&addr, 0, sizeof(addr));
 696
 697     addr.sun_family = AF_UNIX;
 698     strcpy(addr.sun_path, path);
 699     old_umask=umask( ~(access_mask&0777));
 700     if (bind(sfd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
 701         perror("bind()");
 702         close(sfd);
 703         umask(old_umask);
 704         return -1;
 705     }
 706     umask(old_umask);
 707     if (listen(sfd, EBB_MAX_CLIENTS) == -1) {
 708         perror("listen()");
 709         close(sfd);
 710         return -1;
 711     }
 712     return sfd;
 713 }