1 /**
2 * collectd - src/common.h
3 * Copyright (C) 2005-2014 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 * Niki W. Waibel <niki.waibel@gmx.net>
26 **/
28 #ifndef COMMON_H
29 #define COMMON_H
31 #include "collectd.h"
33 #include "plugin.h"
35 #if HAVE_PWD_H
36 # include <pwd.h>
37 #endif
39 #define sfree(ptr) \
40 do { \
41 free(ptr); \
42 (ptr) = NULL; \
43 } while (0)
45 #define STATIC_ARRAY_SIZE(a) (sizeof (a) / sizeof (*(a)))
47 #define IS_TRUE(s) ((strcasecmp ("true", (s)) == 0) \
48 || (strcasecmp ("yes", (s)) == 0) \
49 || (strcasecmp ("on", (s)) == 0))
50 #define IS_FALSE(s) ((strcasecmp ("false", (s)) == 0) \
51 || (strcasecmp ("no", (s)) == 0) \
52 || (strcasecmp ("off", (s)) == 0))
54 struct rate_to_value_state_s
55 {
56 value_t last_value;
57 cdtime_t last_time;
58 gauge_t residual;
59 };
60 typedef struct rate_to_value_state_s rate_to_value_state_t;
62 struct value_to_rate_state_s
63 {
64 value_t last_value;
65 cdtime_t last_time;
66 };
67 typedef struct value_to_rate_state_s value_to_rate_state_t;
69 char *sstrncpy (char *dest, const char *src, size_t n);
71 __attribute__ ((format(printf,3,4)))
72 int ssnprintf (char *dest, size_t n, const char *format, ...);
74 __attribute__ ((format(printf,1,2)))
75 char *ssnprintf_alloc (char const *format, ...);
77 char *sstrdup(const char *s);
78 void *smalloc(size_t size);
79 char *sstrerror (int errnum, char *buf, size_t buflen);
81 /*
82 * NAME
83 * sread
84 *
85 * DESCRIPTION
86 * Reads exactly `n' bytes or fails. Syntax and other behavior is analogous
87 * to `read(2)'. If EOF is received the file descriptor is closed and an
88 * error is returned.
89 *
90 * PARAMETERS
91 * `fd' File descriptor to write to.
92 * `buf' Buffer that is to be written.
93 * `count' Number of bytes in the buffer.
94 *
95 * RETURN VALUE
96 * Zero upon success or non-zero if an error occurred. `errno' is set in this
97 * case.
98 */
99 ssize_t sread (int fd, void *buf, size_t count);
101 /*
102 * NAME
103 * swrite
104 *
105 * DESCRIPTION
106 * Writes exactly `n' bytes or fails. Syntax and other behavior is analogous
107 * to `write(2)'.
108 *
109 * PARAMETERS
110 * `fd' File descriptor to write to.
111 * `buf' Buffer that is to be written.
112 * `count' Number of bytes in the buffer.
113 *
114 * RETURN VALUE
115 * Zero upon success or non-zero if an error occurred. `errno' is set in this
116 * case.
117 */
118 ssize_t swrite (int fd, const void *buf, size_t count);
120 /*
121 * NAME
122 * strsplit
123 *
124 * DESCRIPTION
125 * Splits a string into parts and stores pointers to the parts in `fields'.
126 * The characters split at are: " ", "\t", "\r", and "\n".
127 *
128 * PARAMETERS
129 * `string' String to split. This string will be modified. `fields' will
130 * contain pointers to parts of this string, so free'ing it
131 * will destroy `fields' as well.
132 * `fields' Array of strings where pointers to the parts will be stored.
133 * `size' Number of elements in the array. No more than `size'
134 * pointers will be stored in `fields'.
135 *
136 * RETURN VALUE
137 * Returns the number of parts stored in `fields'.
138 */
139 int strsplit (char *string, char **fields, size_t size);
141 /*
142 * NAME
143 * strjoin
144 *
145 * DESCRIPTION
146 * Joins together several parts of a string using `sep' as a separator. This
147 * is equivalent to the Perl built-in `join'.
148 *
149 * PARAMETERS
150 * `dst' Buffer where the result is stored. Can be NULL if you need to
151 * determine the required buffer size only.
152 * `dst_len' Length of the destination buffer. No more than this many
153 * bytes will be written to the memory pointed to by `dst',
154 * including the trailing null-byte. Must be zero if dst is
155 * NULL.
156 * `fields' Array of strings to be joined.
157 * `fields_num' Number of elements in the `fields' array.
158 * `sep' String to be inserted between any two elements of `fields'.
159 * This string is neither prepended nor appended to the result.
160 * Instead of passing "" (empty string) one can pass NULL.
161 *
162 * RETURN VALUE
163 * Returns the number of characters in the resulting string, excluding a
164 * tailing null byte. If this value is greater than or equal to "dst_len", the
165 * result in "dst" is truncated (but still null terminated). On error a
166 * negative value is returned.
167 */
168 int strjoin (char *dst, size_t dst_len, char **fields, size_t fields_num, const char *sep);
170 /*
171 * NAME
172 * escape_slashes
173 *
174 * DESCRIPTION
175 * Removes slashes ("/") from "buffer". If buffer contains a single slash,
176 * the result will be "root". Leading slashes are removed. All other slashes
177 * are replaced with underscores ("_").
178 * This function is used by plugin_dispatch_values() to escape all parts of
179 * the identifier.
180 *
181 * PARAMETERS
182 * `buffer' String to be escaped.
183 * `buffer_size' Size of the buffer. No more then this many bytes will be
184 * written to `buffer', including the trailing null-byte.
185 *
186 * RETURN VALUE
187 * Returns zero upon success and a value smaller than zero upon failure.
188 */
189 int escape_slashes (char *buffer, size_t buffer_size);
191 /**
192 * NAME
193 * escape_string
194 *
195 * DESCRIPTION
196 * escape_string quotes and escapes a string to be usable with collectd's
197 * plain text protocol. "simple" strings are left as they are, for example if
198 * buffer is 'simple' before the call, it will remain 'simple'. However, if
199 * buffer contains 'more "complex"' before the call, the returned buffer will
200 * contain '"more \"complex\""'.
201 *
202 * If the buffer is too small to contain the escaped string, the string will
203 * be truncated. However, leading and trailing double quotes, as well as an
204 * ending null byte are guaranteed.
205 *
206 * RETURN VALUE
207 * Returns zero on success, even if the string was truncated. Non-zero on
208 * failure.
209 */
210 int escape_string (char *buffer, size_t buffer_size);
212 /*
213 * NAME
214 * replace_special
215 *
216 * DESCRIPTION
217 * Replaces any special characters (anything that's not alpha-numeric or a
218 * dash) with an underscore.
219 *
220 * E.g. "foo$bar&" would become "foo_bar_".
221 *
222 * PARAMETERS
223 * `buffer' String to be handled.
224 * `buffer_size' Length of the string. The function returns after
225 * encountering a null-byte or reading this many bytes.
226 */
227 void replace_special (char *buffer, size_t buffer_size);
229 /*
230 * NAME
231 * strunescape
232 *
233 * DESCRIPTION
234 * Replaces any escaped characters in a string with the appropriate special
235 * characters. The following escaped characters are recognized:
236 *
237 * \t -> <tab>
238 * \n -> <newline>
239 * \r -> <carriage return>
240 *
241 * For all other escacped characters only the backslash will be removed.
242 *
243 * PARAMETERS
244 * `buf' String to be unescaped.
245 * `buf_len' Length of the string, including the terminating null-byte.
246 *
247 * RETURN VALUE
248 * Returns zero upon success, a value less than zero else.
249 */
250 int strunescape (char *buf, size_t buf_len);
252 /**
253 * Removed trailing newline characters (CR and LF) from buffer, which must be
254 * null terminated. Returns the length of the resulting string.
255 */
256 __attribute__((nonnull (1)))
257 size_t strstripnewline (char *buffer);
259 /*
260 * NAME
261 * timeval_cmp
262 *
263 * DESCRIPTION
264 * Compare the two time values `tv0' and `tv1' and store the absolut value
265 * of the difference in the time value pointed to by `delta' if it does not
266 * equal NULL.
267 *
268 * RETURN VALUE
269 * Returns an integer less than, equal to, or greater than zero if `tv0' is
270 * less than, equal to, or greater than `tv1' respectively.
271 */
272 int timeval_cmp (struct timeval tv0, struct timeval tv1, struct timeval *delta);
274 /* make sure tv_usec stores less than a second */
275 #define NORMALIZE_TIMEVAL(tv) \
276 do { \
277 (tv).tv_sec += (tv).tv_usec / 1000000; \
278 (tv).tv_usec = (tv).tv_usec % 1000000; \
279 } while (0)
281 /* make sure tv_sec stores less than a second */
282 #define NORMALIZE_TIMESPEC(tv) \
283 do { \
284 (tv).tv_sec += (tv).tv_nsec / 1000000000; \
285 (tv).tv_nsec = (tv).tv_nsec % 1000000000; \
286 } while (0)
288 int check_create_dir (const char *file_orig);
290 #ifdef HAVE_LIBKSTAT
291 int get_kstat (kstat_t **ksp_ptr, char *module, int instance, char *name);
292 long long get_kstat_value (kstat_t *ksp, char *name);
293 #endif
295 #ifndef HAVE_HTONLL
296 unsigned long long ntohll (unsigned long long n);
297 unsigned long long htonll (unsigned long long n);
298 #endif
300 #if FP_LAYOUT_NEED_NOTHING
301 # define ntohd(d) (d)
302 # define htond(d) (d)
303 #elif FP_LAYOUT_NEED_ENDIANFLIP || FP_LAYOUT_NEED_INTSWAP
304 double ntohd (double d);
305 double htond (double d);
306 #else
307 # error "Don't know how to convert between host and network representation of doubles."
308 #endif
310 int format_name (char *ret, int ret_len,
311 const char *hostname,
312 const char *plugin, const char *plugin_instance,
313 const char *type, const char *type_instance);
314 #define FORMAT_VL(ret, ret_len, vl) \
315 format_name (ret, ret_len, (vl)->host, (vl)->plugin, (vl)->plugin_instance, \
316 (vl)->type, (vl)->type_instance)
317 int format_values (char *ret, size_t ret_len,
318 const data_set_t *ds, const value_list_t *vl,
319 _Bool store_rates);
321 int parse_identifier (char *str, char **ret_host,
322 char **ret_plugin, char **ret_plugin_instance,
323 char **ret_type, char **ret_type_instance,
324 char *default_host);
325 int parse_identifier_vl (const char *str, value_list_t *vl);
326 int parse_value (const char *value, value_t *ret_value, int ds_type);
327 int parse_values (char *buffer, value_list_t *vl, const data_set_t *ds);
329 /* parse_value_file reads "path" and parses its content as an integer or
330 * floating point, depending on "ds_type". On success, the value is stored in
331 * "ret_value" and zero is returned. On failure, a non-zero value is returned. */
332 int parse_value_file (char const *path, value_t *ret_value, int ds_type);
334 #if !HAVE_GETPWNAM_R
335 int getpwnam_r (const char *name, struct passwd *pwbuf, char *buf,
336 size_t buflen, struct passwd **pwbufp);
337 #endif
339 int notification_init (notification_t *n, int severity, const char *message,
340 const char *host,
341 const char *plugin, const char *plugin_instance,
342 const char *type, const char *type_instance);
343 #define NOTIFICATION_INIT_VL(n, vl) \
344 notification_init (n, NOTIF_FAILURE, NULL, \
345 (vl)->host, (vl)->plugin, (vl)->plugin_instance, \
346 (vl)->type, (vl)->type_instance)
348 typedef int (*dirwalk_callback_f)(const char *dirname, const char *filename,
349 void *user_data);
350 int walk_directory (const char *dir, dirwalk_callback_f callback,
351 void *user_data, int hidden);
352 /* Returns the number of bytes read or negative on error. */
353 ssize_t read_file_contents (char const *filename, char *buf, size_t bufsize);
355 counter_t counter_diff (counter_t old_value, counter_t new_value);
357 /* Convert a rate back to a value_t. When converting to a derive_t, counter_t
358 * or absoltue_t, take fractional residuals into account. This is important
359 * when scaling counters, for example.
360 * Returns zero on success. Returns EAGAIN when called for the first time; in
361 * this case the value_t is invalid and the next call should succeed. Other
362 * return values indicate an error. */
363 int rate_to_value (value_t *ret_value, gauge_t rate,
364 rate_to_value_state_t *state, int ds_type, cdtime_t t);
366 int value_to_rate (gauge_t *ret_rate, value_t value, int ds_type, cdtime_t t,
367 value_to_rate_state_t *state);
369 /* Converts a service name (a string) to a port number
370 * (in the range [1-65535]). Returns less than zero on error. */
371 int service_name_to_port_number (const char *service_name);
373 /* Sets various, non-default, socket options */
374 void set_sock_opts (int sockfd);
376 /** Parse a string to a derive_t value. Returns zero on success or non-zero on
377 * failure. If failure is returned, ret_value is not touched. */
378 int strtoderive (const char *string, derive_t *ret_value);
380 /** Parse a string to a gauge_t value. Returns zero on success or non-zero on
381 * failure. If failure is returned, ret_value is not touched. */
382 int strtogauge (const char *string, gauge_t *ret_value);
384 int strarray_add (char ***ret_array, size_t *ret_array_len, char const *str);
385 void strarray_free (char **array, size_t array_len);
387 #ifdef HAVE_SYS_CAPABILITY_H
388 /** Check if the current process benefits from the capability passed in
389 * argument. Returns zero if it does, less than zero if it doesn't or on error.
390 * See capabilities(7) for the list of possible capabilities.
391 * */
392 int check_capability (int capability);
393 #endif /* HAVE_SYS_CAPABILITY_H */
395 #endif /* COMMON_H */