1 /**
2 * collectd - src/utils_format_json.c
3 * Copyright (C) 2009 Florian octo Forster
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Authors:
24 * Florian octo Forster <octo at collectd.org>
25 **/
27 #include "collectd.h"
29 #include "plugin.h"
30 #include "common.h"
32 #include "utils_cache.h"
33 #include "utils_format_json.h"
35 static int json_escape_string (char *buffer, size_t buffer_size, /* {{{ */
36 const char *string)
37 {
38 size_t dst_pos;
40 if ((buffer == NULL) || (string == NULL))
41 return (-EINVAL);
43 if (buffer_size < 3)
44 return (-ENOMEM);
46 dst_pos = 0;
48 #define BUFFER_ADD(c) do { \
49 if (dst_pos >= (buffer_size - 1)) { \
50 buffer[buffer_size - 1] = 0; \
51 return (-ENOMEM); \
52 } \
53 buffer[dst_pos] = (c); \
54 dst_pos++; \
55 } while (0)
57 /* Escape special characters */
58 BUFFER_ADD ('"');
59 for (size_t src_pos = 0; string[src_pos] != 0; src_pos++)
60 {
61 if ((string[src_pos] == '"')
62 || (string[src_pos] == '\\'))
63 {
64 BUFFER_ADD ('\\');
65 BUFFER_ADD (string[src_pos]);
66 }
67 else if (string[src_pos] <= 0x001F)
68 BUFFER_ADD ('?');
69 else
70 BUFFER_ADD (string[src_pos]);
71 } /* for */
72 BUFFER_ADD ('"');
73 buffer[dst_pos] = 0;
75 #undef BUFFER_ADD
77 return (0);
78 } /* }}} int json_escape_string */
80 static int values_to_json (char *buffer, size_t buffer_size, /* {{{ */
81 const data_set_t *ds, const value_list_t *vl, int store_rates)
82 {
83 size_t offset = 0;
84 gauge_t *rates = NULL;
86 memset (buffer, 0, buffer_size);
88 #define BUFFER_ADD(...) do { \
89 int status; \
90 status = ssnprintf (buffer + offset, buffer_size - offset, \
91 __VA_ARGS__); \
92 if (status < 1) \
93 { \
94 sfree(rates); \
95 return (-1); \
96 } \
97 else if (((size_t) status) >= (buffer_size - offset)) \
98 { \
99 sfree(rates); \
100 return (-ENOMEM); \
101 } \
102 else \
103 offset += ((size_t) status); \
104 } while (0)
106 BUFFER_ADD ("[");
107 for (size_t i = 0; i < ds->ds_num; i++)
108 {
109 if (i > 0)
110 BUFFER_ADD (",");
112 if (ds->ds[i].type == DS_TYPE_GAUGE)
113 {
114 if(isfinite (vl->values[i].gauge))
115 BUFFER_ADD (JSON_GAUGE_FORMAT, vl->values[i].gauge);
116 else
117 BUFFER_ADD ("null");
118 }
119 else if (store_rates)
120 {
121 if (rates == NULL)
122 rates = uc_get_rate (ds, vl);
123 if (rates == NULL)
124 {
125 WARNING ("utils_format_json: uc_get_rate failed.");
126 sfree(rates);
127 return (-1);
128 }
130 if(isfinite (rates[i]))
131 BUFFER_ADD (JSON_GAUGE_FORMAT, rates[i]);
132 else
133 BUFFER_ADD ("null");
134 }
135 else if (ds->ds[i].type == DS_TYPE_COUNTER)
136 BUFFER_ADD ("%llu", vl->values[i].counter);
137 else if (ds->ds[i].type == DS_TYPE_DERIVE)
138 BUFFER_ADD ("%"PRIi64, vl->values[i].derive);
139 else if (ds->ds[i].type == DS_TYPE_ABSOLUTE)
140 BUFFER_ADD ("%"PRIu64, vl->values[i].absolute);
141 else
142 {
143 ERROR ("format_json: Unknown data source type: %i",
144 ds->ds[i].type);
145 sfree (rates);
146 return (-1);
147 }
148 } /* for ds->ds_num */
149 BUFFER_ADD ("]");
151 #undef BUFFER_ADD
153 DEBUG ("format_json: values_to_json: buffer = %s;", buffer);
154 sfree(rates);
155 return (0);
156 } /* }}} int values_to_json */
158 static int dstypes_to_json (char *buffer, size_t buffer_size, /* {{{ */
159 const data_set_t *ds)
160 {
161 size_t offset = 0;
163 memset (buffer, 0, buffer_size);
165 #define BUFFER_ADD(...) do { \
166 int status; \
167 status = ssnprintf (buffer + offset, buffer_size - offset, \
168 __VA_ARGS__); \
169 if (status < 1) \
170 return (-1); \
171 else if (((size_t) status) >= (buffer_size - offset)) \
172 return (-ENOMEM); \
173 else \
174 offset += ((size_t) status); \
175 } while (0)
177 BUFFER_ADD ("[");
178 for (size_t i = 0; i < ds->ds_num; i++)
179 {
180 if (i > 0)
181 BUFFER_ADD (",");
183 BUFFER_ADD ("\"%s\"", DS_TYPE_TO_STRING (ds->ds[i].type));
184 } /* for ds->ds_num */
185 BUFFER_ADD ("]");
187 #undef BUFFER_ADD
189 DEBUG ("format_json: dstypes_to_json: buffer = %s;", buffer);
191 return (0);
192 } /* }}} int dstypes_to_json */
194 static int dsnames_to_json (char *buffer, size_t buffer_size, /* {{{ */
195 const data_set_t *ds)
196 {
197 size_t offset = 0;
199 memset (buffer, 0, buffer_size);
201 #define BUFFER_ADD(...) do { \
202 int status; \
203 status = ssnprintf (buffer + offset, buffer_size - offset, \
204 __VA_ARGS__); \
205 if (status < 1) \
206 return (-1); \
207 else if (((size_t) status) >= (buffer_size - offset)) \
208 return (-ENOMEM); \
209 else \
210 offset += ((size_t) status); \
211 } while (0)
213 BUFFER_ADD ("[");
214 for (size_t i = 0; i < ds->ds_num; i++)
215 {
216 if (i > 0)
217 BUFFER_ADD (",");
219 BUFFER_ADD ("\"%s\"", ds->ds[i].name);
220 } /* for ds->ds_num */
221 BUFFER_ADD ("]");
223 #undef BUFFER_ADD
225 DEBUG ("format_json: dsnames_to_json: buffer = %s;", buffer);
227 return (0);
228 } /* }}} int dsnames_to_json */
230 static int meta_data_keys_to_json (char *buffer, size_t buffer_size, /* {{{ */
231 meta_data_t *meta, char **keys, size_t keys_num)
232 {
233 size_t offset = 0;
234 int status;
236 buffer[0] = 0;
238 #define BUFFER_ADD(...) do { \
239 status = ssnprintf (buffer + offset, buffer_size - offset, \
240 __VA_ARGS__); \
241 if (status < 1) \
242 return (-1); \
243 else if (((size_t) status) >= (buffer_size - offset)) \
244 return (-ENOMEM); \
245 else \
246 offset += ((size_t) status); \
247 } while (0)
249 for (size_t i = 0; i < keys_num; ++i)
250 {
251 int type;
252 char *key = keys[i];
254 type = meta_data_type (meta, key);
255 if (type == MD_TYPE_STRING)
256 {
257 char *value = NULL;
258 if (meta_data_get_string (meta, key, &value) == 0)
259 {
260 char temp[512] = "";
262 status = json_escape_string (temp, sizeof (temp), value);
263 sfree (value);
264 if (status != 0)
265 return status;
267 BUFFER_ADD (",\"%s\":%s", key, temp);
268 }
269 }
270 else if (type == MD_TYPE_SIGNED_INT)
271 {
272 int64_t value = 0;
273 if (meta_data_get_signed_int (meta, key, &value) == 0)
274 BUFFER_ADD (",\"%s\":%"PRIi64, key, value);
275 }
276 else if (type == MD_TYPE_UNSIGNED_INT)
277 {
278 uint64_t value = 0;
279 if (meta_data_get_unsigned_int (meta, key, &value) == 0)
280 BUFFER_ADD (",\"%s\":%"PRIu64, key, value);
281 }
282 else if (type == MD_TYPE_DOUBLE)
283 {
284 double value = 0.0;
285 if (meta_data_get_double (meta, key, &value) == 0)
286 BUFFER_ADD (",\"%s\":%f", key, value);
287 }
288 else if (type == MD_TYPE_BOOLEAN)
289 {
290 _Bool value = 0;
291 if (meta_data_get_boolean (meta, key, &value) == 0)
292 BUFFER_ADD (",\"%s\":%s", key, value ? "true" : "false");
293 }
294 } /* for (keys) */
296 if (offset == 0)
297 return (ENOENT);
299 buffer[0] = '{'; /* replace leading ',' */
300 BUFFER_ADD ("}");
302 #undef BUFFER_ADD
304 return (0);
305 } /* }}} int meta_data_keys_to_json */
307 static int meta_data_to_json (char *buffer, size_t buffer_size, /* {{{ */
308 meta_data_t *meta)
309 {
310 char **keys = NULL;
311 size_t keys_num;
312 int status;
314 if ((buffer == NULL) || (buffer_size == 0) || (meta == NULL))
315 return (EINVAL);
317 status = meta_data_toc (meta, &keys);
318 if (status <= 0)
319 return (status);
320 keys_num = (size_t) status;
322 status = meta_data_keys_to_json (buffer, buffer_size, meta, keys, keys_num);
324 for (size_t i = 0; i < keys_num; ++i)
325 sfree (keys[i]);
326 sfree (keys);
328 return status;
329 } /* }}} int meta_data_to_json */
331 static int value_list_to_json (char *buffer, size_t buffer_size, /* {{{ */
332 const data_set_t *ds, const value_list_t *vl, int store_rates)
333 {
334 char temp[512];
335 size_t offset = 0;
336 int status;
338 memset (buffer, 0, buffer_size);
340 #define BUFFER_ADD(...) do { \
341 status = ssnprintf (buffer + offset, buffer_size - offset, \
342 __VA_ARGS__); \
343 if (status < 1) \
344 return (-1); \
345 else if (((size_t) status) >= (buffer_size - offset)) \
346 return (-ENOMEM); \
347 else \
348 offset += ((size_t) status); \
349 } while (0)
351 /* All value lists have a leading comma. The first one will be replaced with
352 * a square bracket in `format_json_finalize'. */
353 BUFFER_ADD (",{");
355 status = values_to_json (temp, sizeof (temp), ds, vl, store_rates);
356 if (status != 0)
357 return (status);
358 BUFFER_ADD ("\"values\":%s", temp);
360 status = dstypes_to_json (temp, sizeof (temp), ds);
361 if (status != 0)
362 return (status);
363 BUFFER_ADD (",\"dstypes\":%s", temp);
365 status = dsnames_to_json (temp, sizeof (temp), ds);
366 if (status != 0)
367 return (status);
368 BUFFER_ADD (",\"dsnames\":%s", temp);
370 BUFFER_ADD (",\"time\":%.3f", CDTIME_T_TO_DOUBLE (vl->time));
371 BUFFER_ADD (",\"interval\":%.3f", CDTIME_T_TO_DOUBLE (vl->interval));
373 #define BUFFER_ADD_KEYVAL(key, value) do { \
374 status = json_escape_string (temp, sizeof (temp), (value)); \
375 if (status != 0) \
376 return (status); \
377 BUFFER_ADD (",\"%s\":%s", (key), temp); \
378 } while (0)
380 BUFFER_ADD_KEYVAL ("host", vl->host);
381 BUFFER_ADD_KEYVAL ("plugin", vl->plugin);
382 BUFFER_ADD_KEYVAL ("plugin_instance", vl->plugin_instance);
383 BUFFER_ADD_KEYVAL ("type", vl->type);
384 BUFFER_ADD_KEYVAL ("type_instance", vl->type_instance);
386 if (vl->meta != NULL)
387 {
388 char meta_buffer[buffer_size];
389 memset (meta_buffer, 0, sizeof (meta_buffer));
390 status = meta_data_to_json (meta_buffer, sizeof (meta_buffer), vl->meta);
391 if (status != 0)
392 return (status);
394 BUFFER_ADD (",\"meta\":%s", meta_buffer);
395 } /* if (vl->meta != NULL) */
397 BUFFER_ADD ("}");
399 #undef BUFFER_ADD_KEYVAL
400 #undef BUFFER_ADD
402 DEBUG ("format_json: value_list_to_json: buffer = %s;", buffer);
404 return (0);
405 } /* }}} int value_list_to_json */
407 static int format_json_value_list_nocheck (char *buffer, /* {{{ */
408 size_t *ret_buffer_fill, size_t *ret_buffer_free,
409 const data_set_t *ds, const value_list_t *vl,
410 int store_rates, size_t temp_size)
411 {
412 char temp[temp_size];
413 int status;
415 status = value_list_to_json (temp, sizeof (temp), ds, vl, store_rates);
416 if (status != 0)
417 return (status);
418 temp_size = strlen (temp);
420 memcpy (buffer + (*ret_buffer_fill), temp, temp_size + 1);
421 (*ret_buffer_fill) += temp_size;
422 (*ret_buffer_free) -= temp_size;
424 return (0);
425 } /* }}} int format_json_value_list_nocheck */
427 int format_json_initialize (char *buffer, /* {{{ */
428 size_t *ret_buffer_fill, size_t *ret_buffer_free)
429 {
430 size_t buffer_fill;
431 size_t buffer_free;
433 if ((buffer == NULL) || (ret_buffer_fill == NULL) || (ret_buffer_free == NULL))
434 return (-EINVAL);
436 buffer_fill = *ret_buffer_fill;
437 buffer_free = *ret_buffer_free;
439 buffer_free = buffer_fill + buffer_free;
440 buffer_fill = 0;
442 if (buffer_free < 3)
443 return (-ENOMEM);
445 memset (buffer, 0, buffer_free);
446 *ret_buffer_fill = buffer_fill;
447 *ret_buffer_free = buffer_free;
449 return (0);
450 } /* }}} int format_json_initialize */
452 int format_json_finalize (char *buffer, /* {{{ */
453 size_t *ret_buffer_fill, size_t *ret_buffer_free)
454 {
455 size_t pos;
457 if ((buffer == NULL) || (ret_buffer_fill == NULL) || (ret_buffer_free == NULL))
458 return (-EINVAL);
460 if (*ret_buffer_free < 2)
461 return (-ENOMEM);
463 /* Replace the leading comma added in `value_list_to_json' with a square
464 * bracket. */
465 if (buffer[0] != ',')
466 return (-EINVAL);
467 buffer[0] = '[';
469 pos = *ret_buffer_fill;
470 buffer[pos] = ']';
471 buffer[pos+1] = 0;
473 (*ret_buffer_fill)++;
474 (*ret_buffer_free)--;
476 return (0);
477 } /* }}} int format_json_finalize */
479 int format_json_value_list (char *buffer, /* {{{ */
480 size_t *ret_buffer_fill, size_t *ret_buffer_free,
481 const data_set_t *ds, const value_list_t *vl, int store_rates)
482 {
483 if ((buffer == NULL)
484 || (ret_buffer_fill == NULL) || (ret_buffer_free == NULL)
485 || (ds == NULL) || (vl == NULL))
486 return (-EINVAL);
488 if (*ret_buffer_free < 3)
489 return (-ENOMEM);
491 return (format_json_value_list_nocheck (buffer,
492 ret_buffer_fill, ret_buffer_free, ds, vl,
493 store_rates, (*ret_buffer_free) - 2));
494 } /* }}} int format_json_value_list */
496 /* vim: set sw=2 sts=2 et fdm=marker : */