src/write_http.c

   1 /**
   2  * collectd - src/write_http.c
   3  * Copyright (C) 2009       Paul Sadauskas
   4  * Copyright (C) 2009       Doug MacEachern
   5  * Copyright (C) 2007-2014  Florian octo Forster
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; only version 2 of the License is applicable.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  19  *
  20  * Authors:
  21  *   Florian octo Forster <octo at collectd.org>
  22  *   Doug MacEachern <dougm@hyperic.com>
  23  *   Paul Sadauskas <psadauskas@gmail.com>
  24  **/
  25
  26 #include "collectd.h"
  27 #include "plugin.h"
  28 #include "common.h"
  29 #include "utils_cache.h"
  30 #include "utils_format_json.h"
  31
  32 #if HAVE_PTHREAD_H
  33 # include <pthread.h>
  34 #endif
  35
  36 #include <curl/curl.h>
  37
  38 #ifndef WRITE_HTTP_DEFAULT_BUFFER_SIZE
  39 # define WRITE_HTTP_DEFAULT_BUFFER_SIZE 4096
  40 #endif
  41
  42 /*
  43  * Private variables
  44  */
  45 struct wh_callback_s
  46 {
  47         char *name;
  48
  49         char *location;
  50         char *user;
  51         char *pass;
  52         char *credentials;
  53         _Bool verify_peer;
  54         _Bool verify_host;
  55         char *cacert;
  56         char *capath;
  57         char *clientkey;
  58         char *clientcert;
  59         char *clientkeypass;
  60         long sslversion;
  61         _Bool store_rates;
  62         int   low_speed_limit;
  63         time_t low_speed_time;
  64         int timeout;
  65
  66 #define WH_FORMAT_COMMAND 0
  67 #define WH_FORMAT_JSON    1
  68         int format;
  69
  70         CURL *curl;
  71         struct curl_slist *headers;
  72         char curl_errbuf[CURL_ERROR_SIZE];
  73
  74         char  *send_buffer;
  75         size_t send_buffer_size;
  76         size_t send_buffer_free;
  77         size_t send_buffer_fill;
  78         cdtime_t send_buffer_init_time;
  79
  80         pthread_mutex_t send_lock;
  81 };
  82 typedef struct wh_callback_s wh_callback_t;
  83
  84 static void wh_reset_buffer (wh_callback_t *cb)  /* {{{ */
  85 {
  86         memset (cb->send_buffer, 0, cb->send_buffer_size);
  87         cb->send_buffer_free = cb->send_buffer_size;
  88         cb->send_buffer_fill = 0;
  89         cb->send_buffer_init_time = cdtime ();
  90
  91         if (cb->format == WH_FORMAT_JSON)
  92         {
  93                 format_json_initialize (cb->send_buffer,
  94                                 &cb->send_buffer_fill,
  95                                 &cb->send_buffer_free);
  96         }
  97 } /* }}} wh_reset_buffer */
  98
  99 static int wh_send_buffer (wh_callback_t *cb) /* {{{ */
 100 {
 101         int status = 0;
 102
 103         curl_easy_setopt (cb->curl, CURLOPT_POSTFIELDS, cb->send_buffer);
 104         status = curl_easy_perform (cb->curl);
 105         if (status != CURLE_OK)
 106         {
 107                 ERROR ("write_http plugin: curl_easy_perform failed with "
 108                                 "status %i: %s",
 109                                 status, cb->curl_errbuf);
 110         }
 111         return (status);
 112 } /* }}} wh_send_buffer */
 113
 114 static int wh_callback_init (wh_callback_t *cb) /* {{{ */
 115 {
 116         if (cb->curl != NULL)
 117                 return (0);
 118
 119         cb->curl = curl_easy_init ();
 120         if (cb->curl == NULL)
 121         {
 122                 ERROR ("curl plugin: curl_easy_init failed.");
 123                 return (-1);
 124         }
 125
 126         if (cb->low_speed_limit > 0 && cb->low_speed_time > 0)
 127         {
 128                 curl_easy_setopt (cb->curl, CURLOPT_LOW_SPEED_LIMIT,
 129                                   (long) (cb->low_speed_limit * cb->low_speed_time));
 130                 curl_easy_setopt (cb->curl, CURLOPT_LOW_SPEED_TIME,
 131                                   (long) cb->low_speed_time);
 132         }
 133
 134 #ifdef HAVE_CURLOPT_TIMEOUT_MS
 135         if (cb->timeout > 0)
 136                 curl_easy_setopt (cb->curl, CURLOPT_TIMEOUT_MS, (long) cb->timeout);
 137 #endif
 138
 139         curl_easy_setopt (cb->curl, CURLOPT_NOSIGNAL, 1L);
 140         curl_easy_setopt (cb->curl, CURLOPT_USERAGENT, COLLECTD_USERAGENT);
 141
 142         cb->headers = NULL;
 143         cb->headers = curl_slist_append (cb->headers, "Accept:  */*");
 144         if (cb->format == WH_FORMAT_JSON)
 145                 cb->headers = curl_slist_append (cb->headers, "Content-Type: application/json");
 146         else
 147                 cb->headers = curl_slist_append (cb->headers, "Content-Type: text/plain");
 148         cb->headers = curl_slist_append (cb->headers, "Expect:");
 149         curl_easy_setopt (cb->curl, CURLOPT_HTTPHEADER, cb->headers);
 150
 151         curl_easy_setopt (cb->curl, CURLOPT_ERRORBUFFER, cb->curl_errbuf);
 152         curl_easy_setopt (cb->curl, CURLOPT_URL, cb->location);
 153         curl_easy_setopt (cb->curl, CURLOPT_FOLLOWLOCATION, 1L);
 154         curl_easy_setopt (cb->curl, CURLOPT_MAXREDIRS, 50L);
 155
 156         if (cb->user != NULL)
 157         {
 158 #ifdef HAVE_CURLOPT_USERNAME
 159                 curl_easy_setopt (cb->curl, CURLOPT_USERNAME, cb->user);
 160                 curl_easy_setopt (cb->curl, CURLOPT_PASSWORD,
 161                         (cb->pass == NULL) ? "" : cb->pass);
 162 #else
 163                 size_t credentials_size;
 164
 165                 credentials_size = strlen (cb->user) + 2;
 166                 if (cb->pass != NULL)
 167                         credentials_size += strlen (cb->pass);
 168
 169                 cb->credentials = (char *) malloc (credentials_size);
 170                 if (cb->credentials == NULL)
 171                 {
 172                         ERROR ("curl plugin: malloc failed.");
 173                         return (-1);
 174                 }
 175
 176                 ssnprintf (cb->credentials, credentials_size, "%s:%s",
 177                                 cb->user, (cb->pass == NULL) ? "" : cb->pass);
 178                 curl_easy_setopt (cb->curl, CURLOPT_USERPWD, cb->credentials);
 179 #endif
 180                 curl_easy_setopt (cb->curl, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 181         }
 182
 183         curl_easy_setopt (cb->curl, CURLOPT_SSL_VERIFYPEER, (long) cb->verify_peer);
 184         curl_easy_setopt (cb->curl, CURLOPT_SSL_VERIFYHOST,
 185                         cb->verify_host ? 2L : 0L);
 186         curl_easy_setopt (cb->curl, CURLOPT_SSLVERSION, cb->sslversion);
 187         if (cb->cacert != NULL)
 188                 curl_easy_setopt (cb->curl, CURLOPT_CAINFO, cb->cacert);
 189         if (cb->capath != NULL)
 190                 curl_easy_setopt (cb->curl, CURLOPT_CAPATH, cb->capath);
 191
 192         if (cb->clientkey != NULL && cb->clientcert != NULL)
 193         {
 194             curl_easy_setopt (cb->curl, CURLOPT_SSLKEY, cb->clientkey);
 195             curl_easy_setopt (cb->curl, CURLOPT_SSLCERT, cb->clientcert);
 196
 197             if (cb->clientkeypass != NULL)
 198                 curl_easy_setopt (cb->curl, CURLOPT_SSLKEYPASSWD, cb->clientkeypass);
 199         }
 200
 201         wh_reset_buffer (cb);
 202
 203         return (0);
 204 } /* }}} int wh_callback_init */
 205
 206 static int wh_flush_nolock (cdtime_t timeout, wh_callback_t *cb) /* {{{ */
 207 {
 208         int status;
 209
 210         DEBUG ("write_http plugin: wh_flush_nolock: timeout = %.3f; "
 211                         "send_buffer_fill = %zu;",
 212                         CDTIME_T_TO_DOUBLE (timeout),
 213                         cb->send_buffer_fill);
 214
 215         /* timeout == 0  => flush unconditionally */
 216         if (timeout > 0)
 217         {
 218                 cdtime_t now;
 219
 220                 now = cdtime ();
 221                 if ((cb->send_buffer_init_time + timeout) > now)
 222                         return (0);
 223         }
 224
 225         if (cb->format == WH_FORMAT_COMMAND)
 226         {
 227                 if (cb->send_buffer_fill <= 0)
 228                 {
 229                         cb->send_buffer_init_time = cdtime ();
 230                         return (0);
 231                 }
 232
 233                 status = wh_send_buffer (cb);
 234                 wh_reset_buffer (cb);
 235         }
 236         else if (cb->format == WH_FORMAT_JSON)
 237         {
 238                 if (cb->send_buffer_fill <= 2)
 239                 {
 240                         cb->send_buffer_init_time = cdtime ();
 241                         return (0);
 242                 }
 243
 244                 status = format_json_finalize (cb->send_buffer,
 245                                 &cb->send_buffer_fill,
 246                                 &cb->send_buffer_free);
 247                 if (status != 0)
 248                 {
 249                         ERROR ("write_http: wh_flush_nolock: "
 250                                         "format_json_finalize failed.");
 251                         wh_reset_buffer (cb);
 252                         return (status);
 253                 }
 254
 255                 status = wh_send_buffer (cb);
 256                 wh_reset_buffer (cb);
 257         }
 258         else
 259         {
 260                 ERROR ("write_http: wh_flush_nolock: "
 261                                 "Unknown format: %i",
 262                                 cb->format);
 263                 return (-1);
 264         }
 265
 266         return (status);
 267 } /* }}} wh_flush_nolock */
 268
 269 static int wh_flush (cdtime_t timeout, /* {{{ */
 270                 const char *identifier __attribute__((unused)),
 271                 user_data_t *user_data)
 272 {
 273         wh_callback_t *cb;
 274         int status;
 275
 276         if (user_data == NULL)
 277                 return (-EINVAL);
 278
 279         cb = user_data->data;
 280
 281         pthread_mutex_lock (&cb->send_lock);
 282
 283         if (cb->curl == NULL)
 284         {
 285                 status = wh_callback_init (cb);
 286                 if (status != 0)
 287                 {
 288                         ERROR ("write_http plugin: wh_callback_init failed.");
 289                         pthread_mutex_unlock (&cb->send_lock);
 290                         return (-1);
 291                 }
 292         }
 293
 294         status = wh_flush_nolock (timeout, cb);
 295         pthread_mutex_unlock (&cb->send_lock);
 296
 297         return (status);
 298 } /* }}} int wh_flush */
 299
 300 static void wh_callback_free (void *data) /* {{{ */
 301 {
 302         wh_callback_t *cb;
 303
 304         if (data == NULL)
 305                 return;
 306
 307         cb = data;
 308
 309         wh_flush_nolock (/* timeout = */ 0, cb);
 310
 311         if (cb->curl != NULL)
 312         {
 313                 curl_easy_cleanup (cb->curl);
 314                 cb->curl = NULL;
 315         }
 316
 317         if (cb->headers != NULL)
 318         {
 319                 curl_slist_free_all (cb->headers);
 320                 cb->headers = NULL;
 321         }
 322
 323         sfree (cb->name);
 324         sfree (cb->location);
 325         sfree (cb->user);
 326         sfree (cb->pass);
 327         sfree (cb->credentials);
 328         sfree (cb->cacert);
 329         sfree (cb->capath);
 330         sfree (cb->clientkey);
 331         sfree (cb->clientcert);
 332         sfree (cb->clientkeypass);
 333         sfree (cb->send_buffer);
 334
 335         sfree (cb);
 336 } /* }}} void wh_callback_free */
 337
 338 static int wh_write_command (const data_set_t *ds, const value_list_t *vl, /* {{{ */
 339                 wh_callback_t *cb)
 340 {
 341         char key[10*DATA_MAX_NAME_LEN];
 342         char values[512];
 343         char command[1024];
 344         size_t command_len;
 345
 346         int status;
 347
 348         if (0 != strcmp (ds->type, vl->type)) {
 349                 ERROR ("write_http plugin: DS type does not match "
 350                                 "value list type");
 351                 return -1;
 352         }
 353
 354         /* Copy the identifier to `key' and escape it. */
 355         status = FORMAT_VL (key, sizeof (key), vl);
 356         if (status != 0) {
 357                 ERROR ("write_http plugin: error with format_name");
 358                 return (status);
 359         }
 360         escape_string (key, sizeof (key));
 361
 362         /* Convert the values to an ASCII representation and put that into
 363          * `values'. */
 364         status = format_values (values, sizeof (values), ds, vl, cb->store_rates);
 365         if (status != 0) {
 366                 ERROR ("write_http plugin: error with "
 367                                 "wh_value_list_to_string");
 368                 return (status);
 369         }
 370
 371         command_len = (size_t) ssnprintf (command, sizeof (command),
 372                         "PUTVAL %s interval=%.3f %s\r\n",
 373                         key,
 374                         CDTIME_T_TO_DOUBLE (vl->interval),
 375                         values);
 376         if (command_len >= sizeof (command)) {
 377                 ERROR ("write_http plugin: Command buffer too small: "
 378                                 "Need %zu bytes.", command_len + 1);
 379                 return (-1);
 380         }
 381
 382         pthread_mutex_lock (&cb->send_lock);
 383
 384         if (cb->curl == NULL)
 385         {
 386                 status = wh_callback_init (cb);
 387                 if (status != 0)
 388                 {
 389                         ERROR ("write_http plugin: wh_callback_init failed.");
 390                         pthread_mutex_unlock (&cb->send_lock);
 391                         return (-1);
 392                 }
 393         }
 394
 395         if (command_len >= cb->send_buffer_free)
 396         {
 397                 status = wh_flush_nolock (/* timeout = */ 0, cb);
 398                 if (status != 0)
 399                 {
 400                         pthread_mutex_unlock (&cb->send_lock);
 401                         return (status);
 402                 }
 403         }
 404         assert (command_len < cb->send_buffer_free);
 405
 406         /* `command_len + 1' because `command_len' does not include the
 407          * trailing null byte. Neither does `send_buffer_fill'. */
 408         memcpy (cb->send_buffer + cb->send_buffer_fill,
 409                         command, command_len + 1);
 410         cb->send_buffer_fill += command_len;
 411         cb->send_buffer_free -= command_len;
 412
 413         DEBUG ("write_http plugin: <%s> buffer %zu/%zu (%g%%) \"%s\"",
 414                         cb->location,
 415                         cb->send_buffer_fill, cb->send_buffer_size,
 416                         100.0 * ((double) cb->send_buffer_fill) / ((double) cb->send_buffer_size),
 417                         command);
 418
 419         /* Check if we have enough space for this command. */
 420         pthread_mutex_unlock (&cb->send_lock);
 421
 422         return (0);
 423 } /* }}} int wh_write_command */
 424
 425 static int wh_write_json (const data_set_t *ds, const value_list_t *vl, /* {{{ */
 426                 wh_callback_t *cb)
 427 {
 428         int status;
 429
 430         pthread_mutex_lock (&cb->send_lock);
 431
 432         if (cb->curl == NULL)
 433         {
 434                 status = wh_callback_init (cb);
 435                 if (status != 0)
 436                 {
 437                         ERROR ("write_http plugin: wh_callback_init failed.");
 438                         pthread_mutex_unlock (&cb->send_lock);
 439                         return (-1);
 440                 }
 441         }
 442
 443         status = format_json_value_list (cb->send_buffer,
 444                         &cb->send_buffer_fill,
 445                         &cb->send_buffer_free,
 446                         ds, vl, cb->store_rates);
 447         if (status == (-ENOMEM))
 448         {
 449                 status = wh_flush_nolock (/* timeout = */ 0, cb);
 450                 if (status != 0)
 451                 {
 452                         wh_reset_buffer (cb);
 453                         pthread_mutex_unlock (&cb->send_lock);
 454                         return (status);
 455                 }
 456
 457                 status = format_json_value_list (cb->send_buffer,
 458                                 &cb->send_buffer_fill,
 459                                 &cb->send_buffer_free,
 460                                 ds, vl, cb->store_rates);
 461         }
 462         if (status != 0)
 463         {
 464                 pthread_mutex_unlock (&cb->send_lock);
 465                 return (status);
 466         }
 467
 468         DEBUG ("write_http plugin: <%s> buffer %zu/%zu (%g%%)",
 469                         cb->location,
 470                         cb->send_buffer_fill, cb->send_buffer_size,
 471                         100.0 * ((double) cb->send_buffer_fill) / ((double) cb->send_buffer_size));
 472
 473         /* Check if we have enough space for this command. */
 474         pthread_mutex_unlock (&cb->send_lock);
 475
 476         return (0);
 477 } /* }}} int wh_write_json */
 478
 479 static int wh_write (const data_set_t *ds, const value_list_t *vl, /* {{{ */
 480                 user_data_t *user_data)
 481 {
 482         wh_callback_t *cb;
 483         int status;
 484
 485         if (user_data == NULL)
 486                 return (-EINVAL);
 487
 488         cb = user_data->data;
 489
 490         if (cb->format == WH_FORMAT_JSON)
 491                 status = wh_write_json (ds, vl, cb);
 492         else
 493                 status = wh_write_command (ds, vl, cb);
 494
 495         return (status);
 496 } /* }}} int wh_write */
 497
 498 static int config_set_format (wh_callback_t *cb, /* {{{ */
 499                 oconfig_item_t *ci)
 500 {
 501         char *string;
 502
 503         if ((ci->values_num != 1)
 504                         || (ci->values[0].type != OCONFIG_TYPE_STRING))
 505         {
 506                 WARNING ("write_http plugin: The `%s' config option "
 507                                 "needs exactly one string argument.", ci->key);
 508                 return (-1);
 509         }
 510
 511         string = ci->values[0].value.string;
 512         if (strcasecmp ("Command", string) == 0)
 513                 cb->format = WH_FORMAT_COMMAND;
 514         else if (strcasecmp ("JSON", string) == 0)
 515                 cb->format = WH_FORMAT_JSON;
 516         else
 517         {
 518                 ERROR ("write_http plugin: Invalid format string: %s",
 519                                 string);
 520                 return (-1);
 521         }
 522
 523         return (0);
 524 } /* }}} int config_set_format */
 525
 526 static int wh_config_node (oconfig_item_t *ci) /* {{{ */
 527 {
 528         wh_callback_t *cb;
 529         int buffer_size = 0;
 530         user_data_t user_data;
 531         char callback_name[DATA_MAX_NAME_LEN];
 532         int i;
 533
 534         cb = malloc (sizeof (*cb));
 535         if (cb == NULL)
 536         {
 537                 ERROR ("write_http plugin: malloc failed.");
 538                 return (-1);
 539         }
 540         memset (cb, 0, sizeof (*cb));
 541         cb->verify_peer = 1;
 542         cb->verify_host = 1;
 543         cb->format = WH_FORMAT_COMMAND;
 544         cb->sslversion = CURL_SSLVERSION_DEFAULT;
 545         cb->low_speed_limit = 0;
 546         cb->timeout = 0;
 547         cb->headers = NULL;
 548
 549         pthread_mutex_init (&cb->send_lock, /* attr = */ NULL);
 550
 551         cf_util_get_string (ci, &cb->name);
 552
 553         /* FIXME: Remove this legacy mode in version 6. */
 554         if (strcasecmp ("URL", ci->key) == 0)
 555                 cf_util_get_string (ci, &cb->location);
 556
 557         for (i = 0; i < ci->children_num; i++)
 558         {
 559                 oconfig_item_t *child = ci->children + i;
 560
 561                 if (strcasecmp ("URL", child->key) == 0)
 562                         cf_util_get_string (child, &cb->location);
 563                 else if (strcasecmp ("User", child->key) == 0)
 564                         cf_util_get_string (child, &cb->user);
 565                 else if (strcasecmp ("Password", child->key) == 0)
 566                         cf_util_get_string (child, &cb->pass);
 567                 else if (strcasecmp ("VerifyPeer", child->key) == 0)
 568                         cf_util_get_boolean (child, &cb->verify_peer);
 569                 else if (strcasecmp ("VerifyHost", child->key) == 0)
 570                         cf_util_get_boolean (child, &cb->verify_host);
 571                 else if (strcasecmp ("CACert", child->key) == 0)
 572                         cf_util_get_string (child, &cb->cacert);
 573                 else if (strcasecmp ("CAPath", child->key) == 0)
 574                         cf_util_get_string (child, &cb->capath);
 575                 else if (strcasecmp ("ClientKey", child->key) == 0)
 576                         cf_util_get_string (child, &cb->clientkey);
 577                 else if (strcasecmp ("ClientCert", child->key) == 0)
 578                         cf_util_get_string (child, &cb->clientcert);
 579                 else if (strcasecmp ("ClientKeyPass", child->key) == 0)
 580                         cf_util_get_string (child, &cb->clientkeypass);
 581                 else if (strcasecmp ("SSLVersion", child->key) == 0)
 582                 {
 583                         char *value = NULL;
 584
 585                         cf_util_get_string (child, &value);
 586
 587                         if (value == NULL || strcasecmp ("default", value) == 0)
 588                                 cb->sslversion = CURL_SSLVERSION_DEFAULT;
 589                         else if (strcasecmp ("SSLv2", value) == 0)
 590                                 cb->sslversion = CURL_SSLVERSION_SSLv2;
 591                         else if (strcasecmp ("SSLv3", value) == 0)
 592                                 cb->sslversion = CURL_SSLVERSION_SSLv3;
 593                         else if (strcasecmp ("TLSv1", value) == 0)
 594                                 cb->sslversion = CURL_SSLVERSION_TLSv1;
 595 #if (LIBCURL_VERSION_MAJOR > 7) || (LIBCURL_VERSION_MAJOR == 7 && LIBCURL_VERSION_MINOR >= 34)
 596                         else if (strcasecmp ("TLSv1_0", value) == 0)
 597                                 cb->sslversion = CURL_SSLVERSION_TLSv1_0;
 598                         else if (strcasecmp ("TLSv1_1", value) == 0)
 599                                 cb->sslversion = CURL_SSLVERSION_TLSv1_1;
 600                         else if (strcasecmp ("TLSv1_2", value) == 0)
 601                                 cb->sslversion = CURL_SSLVERSION_TLSv1_2;
 602 #endif
 603                         else
 604                                 ERROR ("write_http plugin: Invalid SSLVersion "
 605                                                 "option: %s.", value);
 606
 607                         sfree(value);
 608                 }
 609                 else if (strcasecmp ("Format", child->key) == 0)
 610                         config_set_format (cb, child);
 611                 else if (strcasecmp ("StoreRates", child->key) == 0)
 612                         cf_util_get_boolean (child, &cb->store_rates);
 613                 else if (strcasecmp ("BufferSize", child->key) == 0)
 614                         cf_util_get_int (child, &buffer_size);
 615                 else if (strcasecmp ("LowSpeedLimit", child->key) == 0)
 616                         cf_util_get_int (child, &cb->low_speed_limit);
 617                 else if (strcasecmp ("Timeout", child->key) == 0)
 618                         cf_util_get_int (child, &cb->timeout);
 619                 else
 620                 {
 621                         ERROR ("write_http plugin: Invalid configuration "
 622                                         "option: %s.", child->key);
 623                 }
 624         }
 625
 626         if (cb->location == NULL)
 627         {
 628                 ERROR ("write_http plugin: no URL defined for instance '%s'",
 629                         cb->name);
 630                 wh_callback_free (cb);
 631                 return (-1);
 632         }
 633
 634         if (cb->low_speed_limit > 0)
 635                 cb->low_speed_time = CDTIME_T_TO_TIME_T(plugin_get_interval());
 636
 637         /* Determine send_buffer_size. */
 638         cb->send_buffer_size = WRITE_HTTP_DEFAULT_BUFFER_SIZE;
 639         if (buffer_size >= 1024)
 640                 cb->send_buffer_size = (size_t) buffer_size;
 641         else if (buffer_size != 0)
 642                 ERROR ("write_http plugin: Ignoring invalid BufferSize setting (%d).",
 643                                 buffer_size);
 644
 645         /* Allocate the buffer. */
 646         cb->send_buffer = malloc (cb->send_buffer_size);
 647         if (cb->send_buffer == NULL)
 648         {
 649                 ERROR ("write_http plugin: malloc(%zu) failed.", cb->send_buffer_size);
 650                 wh_callback_free (cb);
 651                 return (-1);
 652         }
 653         /* Nulls the buffer and sets ..._free and ..._fill. */
 654         wh_reset_buffer (cb);
 655
 656         ssnprintf (callback_name, sizeof (callback_name), "write_http/%s",
 657                         cb->name);
 658         DEBUG ("write_http: Registering write callback '%s' with URL '%s'",
 659                         callback_name, cb->location);
 660
 661         memset (&user_data, 0, sizeof (user_data));
 662         user_data.data = cb;
 663         user_data.free_func = NULL;
 664         plugin_register_flush (callback_name, wh_flush, &user_data);
 665
 666         user_data.free_func = wh_callback_free;
 667         plugin_register_write (callback_name, wh_write, &user_data);
 668
 669         return (0);
 670 } /* }}} int wh_config_node */
 671
 672 static int wh_config (oconfig_item_t *ci) /* {{{ */
 673 {
 674         int i;
 675
 676         for (i = 0; i < ci->children_num; i++)
 677         {
 678                 oconfig_item_t *child = ci->children + i;
 679
 680                 if (strcasecmp ("Node", child->key) == 0)
 681                         wh_config_node (child);
 682                 /* FIXME: Remove this legacy mode in version 6. */
 683                 else if (strcasecmp ("URL", child->key) == 0) {
 684                         WARNING ("write_http plugin: Legacy <URL> block found. "
 685                                 "Please use <Node> instead.");
 686                         wh_config_node (child);
 687                 }
 688                 else
 689                 {
 690                         ERROR ("write_http plugin: Invalid configuration "
 691                                         "option: %s.", child->key);
 692                 }
 693         }
 694
 695         return (0);
 696 } /* }}} int wh_config */
 697
 698 static int wh_init (void) /* {{{ */
 699 {
 700         /* Call this while collectd is still single-threaded to avoid
 701          * initialization issues in libgcrypt. */
 702         curl_global_init (CURL_GLOBAL_SSL);
 703         return (0);
 704 } /* }}} int wh_init */
 705
 706 void module_register (void) /* {{{ */
 707 {
 708         plugin_register_complex_config ("write_http", wh_config);
 709         plugin_register_init ("write_http", wh_init);
 710 } /* }}} void module_register */
 711
 712 /* vim: set fdm=marker sw=8 ts=8 tw=78 et : */