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) \
48 ((strcasecmp("true", (s)) == 0) || (strcasecmp("yes", (s)) == 0) || \
49 (strcasecmp("on", (s)) == 0))
50 #define IS_FALSE(s) \
51 ((strcasecmp("false", (s)) == 0) || (strcasecmp("no", (s)) == 0) || \
52 (strcasecmp("off", (s)) == 0))
54 struct rate_to_value_state_s {
55 value_t last_value;
56 cdtime_t last_time;
57 gauge_t residual;
58 };
59 typedef struct rate_to_value_state_s rate_to_value_state_t;
61 struct value_to_rate_state_s {
62 value_t last_value;
63 cdtime_t last_time;
64 };
65 typedef struct value_to_rate_state_s value_to_rate_state_t;
67 char *sstrncpy(char *dest, const char *src, size_t n);
69 __attribute__((format(printf, 3, 4))) int ssnprintf(char *dest, size_t n,
70 const char *format, ...);
72 __attribute__((format(printf, 1, 2))) char *ssnprintf_alloc(char const *format,
73 ...);
75 char *sstrdup(const char *s);
76 void *smalloc(size_t size);
77 char *sstrerror(int errnum, char *buf, size_t buflen);
79 /*
80 * NAME
81 * sread
82 *
83 * DESCRIPTION
84 * Reads exactly `n' bytes or fails. Syntax and other behavior is analogous
85 * to `read(2)'. If EOF is received the file descriptor is closed and an
86 * error is returned.
87 *
88 * PARAMETERS
89 * `fd' File descriptor to write to.
90 * `buf' Buffer that is to be written.
91 * `count' Number of bytes in the buffer.
92 *
93 * RETURN VALUE
94 * Zero upon success or non-zero if an error occurred. `errno' is set in this
95 * case.
96 */
97 ssize_t sread(int fd, void *buf, size_t count);
99 /*
100 * NAME
101 * swrite
102 *
103 * DESCRIPTION
104 * Writes exactly `n' bytes or fails. Syntax and other behavior is analogous
105 * to `write(2)'.
106 *
107 * PARAMETERS
108 * `fd' File descriptor to write to.
109 * `buf' Buffer that is to be written.
110 * `count' Number of bytes in the buffer.
111 *
112 * RETURN VALUE
113 * Zero upon success or non-zero if an error occurred. `errno' is set in this
114 * case.
115 */
116 ssize_t swrite(int fd, const void *buf, size_t count);
118 /*
119 * NAME
120 * strsplit
121 *
122 * DESCRIPTION
123 * Splits a string into parts and stores pointers to the parts in `fields'.
124 * The characters split at are: " ", "\t", "\r", and "\n".
125 *
126 * PARAMETERS
127 * `string' String to split. This string will be modified. `fields' will
128 * contain pointers to parts of this string, so free'ing it
129 * will destroy `fields' as well.
130 * `fields' Array of strings where pointers to the parts will be stored.
131 * `size' Number of elements in the array. No more than `size'
132 * pointers will be stored in `fields'.
133 *
134 * RETURN VALUE
135 * Returns the number of parts stored in `fields'.
136 */
137 int strsplit(char *string, char **fields, size_t size);
139 /*
140 * NAME
141 * strjoin
142 *
143 * DESCRIPTION
144 * Joins together several parts of a string using `sep' as a separator. This
145 * is equivalent to the Perl built-in `join'.
146 *
147 * PARAMETERS
148 * `dst' Buffer where the result is stored.
149 * `dst_len' Length of the destination buffer. No more than this many
150 * bytes will be written to the memory pointed to by `dst',
151 * including the trailing null-byte.
152 * `fields' Array of strings to be joined.
153 * `fields_num' Number of elements in the `fields' array.
154 * `sep' String to be inserted between any two elements of `fields'.
155 * This string is neither prepended nor appended to the result.
156 * Instead of passing "" (empty string) one can pass NULL.
157 *
158 * RETURN VALUE
159 * Returns the number of characters in `dst', NOT including the trailing
160 * null-byte. If an error occurred (empty array or `dst' too small) a value
161 * smaller than zero will be returned.
162 */
163 int strjoin(char *dst, size_t dst_len, char **fields, size_t fields_num,
164 const char *sep);
166 /*
167 * NAME
168 * escape_slashes
169 *
170 * DESCRIPTION
171 * Removes slashes ("/") from "buffer". If buffer contains a single slash,
172 * the result will be "root". Leading slashes are removed. All other slashes
173 * are replaced with underscores ("_").
174 * This function is used by plugin_dispatch_values() to escape all parts of
175 * the identifier.
176 *
177 * PARAMETERS
178 * `buffer' String to be escaped.
179 * `buffer_size' Size of the buffer. No more then this many bytes will be
180 * written to `buffer', including the trailing null-byte.
181 *
182 * RETURN VALUE
183 * Returns zero upon success and a value smaller than zero upon failure.
184 */
185 int escape_slashes(char *buffer, size_t buffer_size);
187 /**
188 * NAME
189 * escape_string
190 *
191 * DESCRIPTION
192 * escape_string quotes and escapes a string to be usable with collectd's
193 * plain text protocol. "simple" strings are left as they are, for example if
194 * buffer is 'simple' before the call, it will remain 'simple'. However, if
195 * buffer contains 'more "complex"' before the call, the returned buffer will
196 * contain '"more \"complex\""'.
197 *
198 * If the buffer is too small to contain the escaped string, the string will
199 * be truncated. However, leading and trailing double quotes, as well as an
200 * ending null byte are guaranteed.
201 *
202 * RETURN VALUE
203 * Returns zero on success, even if the string was truncated. Non-zero on
204 * failure.
205 */
206 int escape_string(char *buffer, size_t buffer_size);
208 /*
209 * NAME
210 * replace_special
211 *
212 * DESCRIPTION
213 * Replaces any special characters (anything that's not alpha-numeric or a
214 * dash) with an underscore.
215 *
216 * E.g. "foo$bar&" would become "foo_bar_".
217 *
218 * PARAMETERS
219 * `buffer' String to be handled.
220 * `buffer_size' Length of the string. The function returns after
221 * encountering a null-byte or reading this many bytes.
222 */
223 void replace_special(char *buffer, size_t buffer_size);
225 /*
226 * NAME
227 * strunescape
228 *
229 * DESCRIPTION
230 * Replaces any escaped characters in a string with the appropriate special
231 * characters. The following escaped characters are recognized:
232 *
233 * \t -> <tab>
234 * \n -> <newline>
235 * \r -> <carriage return>
236 *
237 * For all other escacped characters only the backslash will be removed.
238 *
239 * PARAMETERS
240 * `buf' String to be unescaped.
241 * `buf_len' Length of the string, including the terminating null-byte.
242 *
243 * RETURN VALUE
244 * Returns zero upon success, a value less than zero else.
245 */
246 int strunescape(char *buf, size_t buf_len);
248 /**
249 * Removed trailing newline characters (CR and LF) from buffer, which must be
250 * null terminated. Returns the length of the resulting string.
251 */
252 __attribute__((nonnull(1))) size_t strstripnewline(char *buffer);
254 /*
255 * NAME
256 * timeval_cmp
257 *
258 * DESCRIPTION
259 * Compare the two time values `tv0' and `tv1' and store the absolut value
260 * of the difference in the time value pointed to by `delta' if it does not
261 * equal NULL.
262 *
263 * RETURN VALUE
264 * Returns an integer less than, equal to, or greater than zero if `tv0' is
265 * less than, equal to, or greater than `tv1' respectively.
266 */
267 int timeval_cmp(struct timeval tv0, struct timeval tv1, struct timeval *delta);
269 /* make sure tv_usec stores less than a second */
270 #define NORMALIZE_TIMEVAL(tv) \
271 do { \
272 (tv).tv_sec += (tv).tv_usec / 1000000; \
273 (tv).tv_usec = (tv).tv_usec % 1000000; \
274 } while (0)
276 /* make sure tv_sec stores less than a second */
277 #define NORMALIZE_TIMESPEC(tv) \
278 do { \
279 (tv).tv_sec += (tv).tv_nsec / 1000000000; \
280 (tv).tv_nsec = (tv).tv_nsec % 1000000000; \
281 } while (0)
283 int check_create_dir(const char *file_orig);
285 #ifdef HAVE_LIBKSTAT
286 int get_kstat(kstat_t **ksp_ptr, char *module, int instance, char *name);
287 long long get_kstat_value(kstat_t *ksp, char *name);
288 #endif
290 #ifndef HAVE_HTONLL
291 unsigned long long ntohll(unsigned long long n);
292 unsigned long long htonll(unsigned long long n);
293 #endif
295 #if FP_LAYOUT_NEED_NOTHING
296 #define ntohd(d) (d)
297 #define htond(d) (d)
298 #elif FP_LAYOUT_NEED_ENDIANFLIP || FP_LAYOUT_NEED_INTSWAP
299 double ntohd(double d);
300 double htond(double d);
301 #else
302 #error \
303 "Don't know how to convert between host and network representation of doubles."
304 #endif
306 int format_name(char *ret, int ret_len, const char *hostname,
307 const char *plugin, const char *plugin_instance,
308 const char *type, const char *type_instance);
309 #define FORMAT_VL(ret, ret_len, vl) \
310 format_name(ret, ret_len, (vl)->host, (vl)->plugin, (vl)->plugin_instance, \
311 (vl)->type, (vl)->type_instance)
312 int format_values(char *ret, size_t ret_len, const data_set_t *ds,
313 const value_list_t *vl, _Bool store_rates);
315 int parse_identifier(char *str, char **ret_host, char **ret_plugin,
316 char **ret_plugin_instance, char **ret_type,
317 char **ret_type_instance);
318 int parse_identifier_vl(const char *str, value_list_t *vl);
319 int parse_value(const char *value, value_t *ret_value, int ds_type);
320 int parse_values(char *buffer, value_list_t *vl, const data_set_t *ds);
322 #if !HAVE_GETPWNAM_R
323 int getpwnam_r(const char *name, struct passwd *pwbuf, char *buf, size_t buflen,
324 struct passwd **pwbufp);
325 #endif
327 int notification_init(notification_t *n, int severity, const char *message,
328 const char *host, const char *plugin,
329 const char *plugin_instance, const char *type,
330 const char *type_instance);
331 #define NOTIFICATION_INIT_VL(n, vl) \
332 notification_init(n, NOTIF_FAILURE, NULL, (vl)->host, (vl)->plugin, \
333 (vl)->plugin_instance, (vl)->type, (vl)->type_instance)
335 typedef int (*dirwalk_callback_f)(const char *dirname, const char *filename,
336 void *user_data);
337 int walk_directory(const char *dir, dirwalk_callback_f callback,
338 void *user_data, int hidden);
339 /* Returns the number of bytes read or negative on error. */
340 ssize_t read_file_contents(char const *filename, char *buf, size_t bufsize);
342 counter_t counter_diff(counter_t old_value, counter_t new_value);
344 /* Convert a rate back to a value_t. When converting to a derive_t, counter_t
345 * or absoltue_t, take fractional residuals into account. This is important
346 * when scaling counters, for example.
347 * Returns zero on success. Returns EAGAIN when called for the first time; in
348 * this case the value_t is invalid and the next call should succeed. Other
349 * return values indicate an error. */
350 int rate_to_value(value_t *ret_value, gauge_t rate,
351 rate_to_value_state_t *state, int ds_type, cdtime_t t);
353 int value_to_rate(gauge_t *ret_rate, value_t value, int ds_type, cdtime_t t,
354 value_to_rate_state_t *state);
356 /* Converts a service name (a string) to a port number
357 * (in the range [1-65535]). Returns less than zero on error. */
358 int service_name_to_port_number(const char *service_name);
360 /* Sets various, non-default, socket options */
361 void set_sock_opts(int sockfd);
363 /** Parse a string to a derive_t value. Returns zero on success or non-zero on
364 * failure. If failure is returned, ret_value is not touched. */
365 int strtoderive(const char *string, derive_t *ret_value);
367 /** Parse a string to a gauge_t value. Returns zero on success or non-zero on
368 * failure. If failure is returned, ret_value is not touched. */
369 int strtogauge(const char *string, gauge_t *ret_value);
371 int strarray_add(char ***ret_array, size_t *ret_array_len, char const *str);
372 void strarray_free(char **array, size_t array_len);
374 #ifdef HAVE_SYS_CAPABILITY_H
375 /** Check if the current process benefits from the capability passed in
376 * argument. Returns zero if it does, less than zero if it doesn't or on error.
377 * See capabilities(7) for the list of possible capabilities.
378 * */
379 int check_capability(int capability);
380 #endif /* HAVE_SYS_CAPABILITY_H */
382 #endif /* COMMON_H */