Merge branch 'collectd-5.4' into collectd-5.5

diff --combined src/sigrok.c
index eecb54c,1a0536a..487f31a
--- 1/src/sigrok.c
--- 2/src/sigrok.c
+++ b/src/sigrok.c
@@@ -1,6 -1,6 +1,6 @@@
  /*
   * collectd - src/sigrok.c
 - * Copyright (C) 2013 Bert Vermeulen <bert@biot.com>
 + * Copyright (C) 2013 Bert Vermeulen
   *
   * This program is free software: you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
@@@ -14,9 -14,6 +14,9 @@@
   *
   * You should have received a copy of the GNU General Public License
   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 + *
 + * Authors:
 + *   Bert Vermeulen <bert at biot.com>
   */
  
  #include "collectd.h"
@@@ -360,10 -357,13 +360,13 @@@ static int sigrok_init(void
                return -1;
        }
  
-       if ((status = plugin_thread_create(&sr_thread, NULL, sigrok_read_thread,
-                       NULL)) != 0) {
+       status = plugin_thread_create(&sr_thread, NULL, sigrok_read_thread,
+                       NULL);
+       if (status != 0)
+       {
+               char errbuf[1024];
                ERROR("sigrok plugin: Failed to create thread: %s.",
-                               strerror(status));
+                               sstrerror (errno, errbuf, sizeof (errbuf)));
                return -1;
        }
        sr_thread_running = TRUE;

diff --combined src/utils_format_json.c
index 10a5343,8d46edd..23a0fdf
--- 1/src/utils_format_json.c
--- 2/src/utils_format_json.c
+++ b/src/utils_format_json.c
@@@ -1,27 -1,22 +1,27 @@@
  /**
   * collectd - src/utils_format_json.c
 - * Copyright (C) 2009  Florian octo Forster
 + * Copyright (C) 2009       Florian octo Forster
   *
 - * This program is free software; you can redistribute it and/or modify it
 - * under the terms of the GNU General Public License as published by the
 - * Free Software Foundation; only version 2 of the License is applicable.
 + * Permission is hereby granted, free of charge, to any person obtaining a
 + * copy of this software and associated documentation files (the "Software"),
 + * to deal in the Software without restriction, including without limitation
 + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 + * and/or sell copies of the Software, and to permit persons to whom the
 + * Software is furnished to do so, subject to the following conditions:
   *
 - * This program is distributed in the hope that it will be useful, but
 - * WITHOUT ANY WARRANTY; without even the implied warranty of
 - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 - * General Public License for more details.
 + * The above copyright notice and this permission notice shall be included in
 + * all copies or substantial portions of the Software.
   *
 - * You should have received a copy of the GNU General Public License along
 - * with this program; if not, write to the Free Software Foundation, Inc.,
 - * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 + * DEALINGS IN THE SOFTWARE.
   *
   * Authors:
 - *   Florian octo Forster <octo at verplant.org>
 + *   Florian octo Forster <octo at collectd.org>
   **/
  
  #include "collectd.h"
@@@ -31,7 -26,7 +31,7 @@@
  #include "utils_cache.h"
  #include "utils_format_json.h"
  
 -static int escape_string (char *buffer, size_t buffer_size, /* {{{ */
 +static int json_escape_string (char *buffer, size_t buffer_size, /* {{{ */
      const char *string)
  {
    size_t src_pos;
@@@ -75,7 -70,7 +75,7 @@@
  #undef BUFFER_ADD
  
    return (0);
 -} /* }}} int escape_string */
 +} /* }}} int json_escape_string */
  
  static int values_to_json (char *buffer, size_t buffer_size, /* {{{ */
                  const data_set_t *ds, const value_list_t *vl, int store_rates)
@@@ -230,20 -225,15 +230,15 @@@ static int dsnames_to_json (char *buffe
    return (0);
  } /* }}} int dsnames_to_json */
  
- static int meta_data_to_json (char *buffer, size_t buffer_size, /* {{{ */
-     meta_data_t *meta)
+ static int meta_data_keys_to_json (char *buffer, size_t buffer_size, /* {{{ */
+     meta_data_t *meta, char **keys, size_t keys_num)
  {
    size_t offset = 0;
-   char **keys = NULL;
-   int keys_num;
    int status;
-   int i;
+   size_t i;
  
    buffer[0] = 0;
  
-   if (meta == NULL)
-     return (EINVAL);
- 
  #define BUFFER_ADD(...) do { \
    status = ssnprintf (buffer + offset, buffer_size - offset, \
        __VA_ARGS__); \
@@@ -255,13 -245,6 +250,6 @@@
      offset += ((size_t) status); \
  } while (0)
  
-   keys_num = meta_data_toc (meta, &keys);
-   if (keys_num == 0)
-   {
-     sfree (keys);
-     return (0);
-   }
- 
    for (i = 0; i < keys_num; ++i)
    {
      int type;
@@@ -274,7 -257,7 +262,7 @@@
        if (meta_data_get_string (meta, key, &value) == 0)
        {
          char temp[512] = "";
 -        escape_string (temp, sizeof (temp), value);
 +        json_escape_string (temp, sizeof (temp), value);
          sfree (value);
          BUFFER_ADD (",\"%s\":%s", key, temp);
        }
@@@ -303,10 -286,7 +291,7 @@@
        if (meta_data_get_boolean (meta, key, &value) == 0)
          BUFFER_ADD (",\"%s\":%s", key, value ? "true" : "false");
      }
- 
-     free (key);
    } /* for (keys) */
-   free (keys);
  
    if (offset <= 0)
      return (ENOENT);
@@@ -317,6 -297,31 +302,31 @@@
  #undef BUFFER_ADD
  
    return (0);
+ } /* }}} int meta_data_keys_to_json */
+ 
+ static int meta_data_to_json (char *buffer, size_t buffer_size, /* {{{ */
+     meta_data_t *meta)
+ {
+   char **keys = NULL;
+   size_t keys_num;
+   int status;
+   size_t i;
+ 
+   if ((buffer == NULL) || (buffer_size == 0) || (meta == NULL))
+     return (EINVAL);
+ 
+   status = meta_data_toc (meta, &keys);
+   if (status <= 0)
+     return (status);
+   keys_num = (size_t) status;
+ 
+   status = meta_data_keys_to_json (buffer, buffer_size, meta, keys, keys_num);
+ 
+   for (i = 0; i < keys_num; ++i)
+     sfree (keys[i]);
+   sfree (keys);
+ 
+   return status;
  } /* }}} int meta_data_to_json */
  
  static int value_list_to_json (char *buffer, size_t buffer_size, /* {{{ */
@@@ -362,7 -367,7 +372,7 @@@
    BUFFER_ADD (",\"interval\":%.3f", CDTIME_T_TO_DOUBLE (vl->interval));
  
  #define BUFFER_ADD_KEYVAL(key, value) do { \
 -  status = escape_string (temp, sizeof (temp), (value)); \
 +  status = json_escape_string (temp, sizeof (temp), (value)); \
    if (status != 0) \
      return (status); \
    BUFFER_ADD (",\"%s\":%s", (key), temp); \