xref: /freebsd/contrib/wpa/src/utils/os.h (revision ceae90c295a309e0196ef7e7e0456f27a0eefb85)
1 /*
2  * OS specific functions
3  * Copyright (c) 2005-2009, Jouni Malinen <j@w1.fi>
4  *
5  * This software may be distributed under the terms of the BSD license.
6  * See README for more details.
7  */
8 
9 #ifndef OS_H
10 #define OS_H
11 
12 typedef long os_time_t;
13 
14 /**
15  * os_sleep - Sleep (sec, usec)
16  * @sec: Number of seconds to sleep
17  * @usec: Number of microseconds to sleep
18  */
19 void os_sleep(os_time_t sec, os_time_t usec);
20 
21 struct os_time {
22 	os_time_t sec;
23 	os_time_t usec;
24 };
25 
26 /**
27  * os_get_time - Get current time (sec, usec)
28  * @t: Pointer to buffer for the time
29  * Returns: 0 on success, -1 on failure
30  */
31 int os_get_time(struct os_time *t);
32 
33 
34 /* Helper macros for handling struct os_time */
35 
36 #define os_time_before(a, b) \
37 	((a)->sec < (b)->sec || \
38 	 ((a)->sec == (b)->sec && (a)->usec < (b)->usec))
39 
40 #define os_time_sub(a, b, res) do { \
41 	(res)->sec = (a)->sec - (b)->sec; \
42 	(res)->usec = (a)->usec - (b)->usec; \
43 	if ((res)->usec < 0) { \
44 		(res)->sec--; \
45 		(res)->usec += 1000000; \
46 	} \
47 } while (0)
48 
49 /**
50  * os_mktime - Convert broken-down time into seconds since 1970-01-01
51  * @year: Four digit year
52  * @month: Month (1 .. 12)
53  * @day: Day of month (1 .. 31)
54  * @hour: Hour (0 .. 23)
55  * @min: Minute (0 .. 59)
56  * @sec: Second (0 .. 60)
57  * @t: Buffer for returning calendar time representation (seconds since
58  * 1970-01-01 00:00:00)
59  * Returns: 0 on success, -1 on failure
60  *
61  * Note: The result is in seconds from Epoch, i.e., in UTC, not in local time
62  * which is used by POSIX mktime().
63  */
64 int os_mktime(int year, int month, int day, int hour, int min, int sec,
65 	      os_time_t *t);
66 
67 struct os_tm {
68 	int sec; /* 0..59 or 60 for leap seconds */
69 	int min; /* 0..59 */
70 	int hour; /* 0..23 */
71 	int day; /* 1..31 */
72 	int month; /* 1..12 */
73 	int year; /* Four digit year */
74 };
75 
76 int os_gmtime(os_time_t t, struct os_tm *tm);
77 
78 /**
79  * os_daemonize - Run in the background (detach from the controlling terminal)
80  * @pid_file: File name to write the process ID to or %NULL to skip this
81  * Returns: 0 on success, -1 on failure
82  */
83 int os_daemonize(const char *pid_file);
84 
85 /**
86  * os_daemonize_terminate - Stop running in the background (remove pid file)
87  * @pid_file: File name to write the process ID to or %NULL to skip this
88  */
89 void os_daemonize_terminate(const char *pid_file);
90 
91 /**
92  * os_get_random - Get cryptographically strong pseudo random data
93  * @buf: Buffer for pseudo random data
94  * @len: Length of the buffer
95  * Returns: 0 on success, -1 on failure
96  */
97 int os_get_random(unsigned char *buf, size_t len);
98 
99 /**
100  * os_random - Get pseudo random value (not necessarily very strong)
101  * Returns: Pseudo random value
102  */
103 unsigned long os_random(void);
104 
105 /**
106  * os_rel2abs_path - Get an absolute path for a file
107  * @rel_path: Relative path to a file
108  * Returns: Absolute path for the file or %NULL on failure
109  *
110  * This function tries to convert a relative path of a file to an absolute path
111  * in order for the file to be found even if current working directory has
112  * changed. The returned value is allocated and caller is responsible for
113  * freeing it. It is acceptable to just return the same path in an allocated
114  * buffer, e.g., return strdup(rel_path). This function is only used to find
115  * configuration files when os_daemonize() may have changed the current working
116  * directory and relative path would be pointing to a different location.
117  */
118 char * os_rel2abs_path(const char *rel_path);
119 
120 /**
121  * os_program_init - Program initialization (called at start)
122  * Returns: 0 on success, -1 on failure
123  *
124  * This function is called when a programs starts. If there are any OS specific
125  * processing that is needed, it can be placed here. It is also acceptable to
126  * just return 0 if not special processing is needed.
127  */
128 int os_program_init(void);
129 
130 /**
131  * os_program_deinit - Program deinitialization (called just before exit)
132  *
133  * This function is called just before a program exists. If there are any OS
134  * specific processing, e.g., freeing resourced allocated in os_program_init(),
135  * it should be done here. It is also acceptable for this function to do
136  * nothing.
137  */
138 void os_program_deinit(void);
139 
140 /**
141  * os_setenv - Set environment variable
142  * @name: Name of the variable
143  * @value: Value to set to the variable
144  * @overwrite: Whether existing variable should be overwritten
145  * Returns: 0 on success, -1 on error
146  *
147  * This function is only used for wpa_cli action scripts. OS wrapper does not
148  * need to implement this if such functionality is not needed.
149  */
150 int os_setenv(const char *name, const char *value, int overwrite);
151 
152 /**
153  * os_unsetenv - Delete environent variable
154  * @name: Name of the variable
155  * Returns: 0 on success, -1 on error
156  *
157  * This function is only used for wpa_cli action scripts. OS wrapper does not
158  * need to implement this if such functionality is not needed.
159  */
160 int os_unsetenv(const char *name);
161 
162 /**
163  * os_readfile - Read a file to an allocated memory buffer
164  * @name: Name of the file to read
165  * @len: For returning the length of the allocated buffer
166  * Returns: Pointer to the allocated buffer or %NULL on failure
167  *
168  * This function allocates memory and reads the given file to this buffer. Both
169  * binary and text files can be read with this function. The caller is
170  * responsible for freeing the returned buffer with os_free().
171  */
172 char * os_readfile(const char *name, size_t *len);
173 
174 /**
175  * os_zalloc - Allocate and zero memory
176  * @size: Number of bytes to allocate
177  * Returns: Pointer to allocated and zeroed memory or %NULL on failure
178  *
179  * Caller is responsible for freeing the returned buffer with os_free().
180  */
181 void * os_zalloc(size_t size);
182 
183 /**
184  * os_calloc - Allocate and zero memory for an array
185  * @nmemb: Number of members in the array
186  * @size: Number of bytes in each member
187  * Returns: Pointer to allocated and zeroed memory or %NULL on failure
188  *
189  * This function can be used as a wrapper for os_zalloc(nmemb * size) when an
190  * allocation is used for an array. The main benefit over os_zalloc() is in
191  * having an extra check to catch integer overflows in multiplication.
192  *
193  * Caller is responsible for freeing the returned buffer with os_free().
194  */
195 static inline void * os_calloc(size_t nmemb, size_t size)
196 {
197 	if (size && nmemb > (~(size_t) 0) / size)
198 		return NULL;
199 	return os_zalloc(nmemb * size);
200 }
201 
202 
203 /*
204  * The following functions are wrapper for standard ANSI C or POSIX functions.
205  * By default, they are just defined to use the standard function name and no
206  * os_*.c implementation is needed for them. This avoids extra function calls
207  * by allowing the C pre-processor take care of the function name mapping.
208  *
209  * If the target system uses a C library that does not provide these functions,
210  * build_config.h can be used to define the wrappers to use a different
211  * function name. This can be done on function-by-function basis since the
212  * defines here are only used if build_config.h does not define the os_* name.
213  * If needed, os_*.c file can be used to implement the functions that are not
214  * included in the C library on the target system. Alternatively,
215  * OS_NO_C_LIB_DEFINES can be defined to skip all defines here in which case
216  * these functions need to be implemented in os_*.c file for the target system.
217  */
218 
219 #ifdef OS_NO_C_LIB_DEFINES
220 
221 /**
222  * os_malloc - Allocate dynamic memory
223  * @size: Size of the buffer to allocate
224  * Returns: Allocated buffer or %NULL on failure
225  *
226  * Caller is responsible for freeing the returned buffer with os_free().
227  */
228 void * os_malloc(size_t size);
229 
230 /**
231  * os_realloc - Re-allocate dynamic memory
232  * @ptr: Old buffer from os_malloc() or os_realloc()
233  * @size: Size of the new buffer
234  * Returns: Allocated buffer or %NULL on failure
235  *
236  * Caller is responsible for freeing the returned buffer with os_free().
237  * If re-allocation fails, %NULL is returned and the original buffer (ptr) is
238  * not freed and caller is still responsible for freeing it.
239  */
240 void * os_realloc(void *ptr, size_t size);
241 
242 /**
243  * os_free - Free dynamic memory
244  * @ptr: Old buffer from os_malloc() or os_realloc(); can be %NULL
245  */
246 void os_free(void *ptr);
247 
248 /**
249  * os_memcpy - Copy memory area
250  * @dest: Destination
251  * @src: Source
252  * @n: Number of bytes to copy
253  * Returns: dest
254  *
255  * The memory areas src and dst must not overlap. os_memmove() can be used with
256  * overlapping memory.
257  */
258 void * os_memcpy(void *dest, const void *src, size_t n);
259 
260 /**
261  * os_memmove - Copy memory area
262  * @dest: Destination
263  * @src: Source
264  * @n: Number of bytes to copy
265  * Returns: dest
266  *
267  * The memory areas src and dst may overlap.
268  */
269 void * os_memmove(void *dest, const void *src, size_t n);
270 
271 /**
272  * os_memset - Fill memory with a constant byte
273  * @s: Memory area to be filled
274  * @c: Constant byte
275  * @n: Number of bytes started from s to fill with c
276  * Returns: s
277  */
278 void * os_memset(void *s, int c, size_t n);
279 
280 /**
281  * os_memcmp - Compare memory areas
282  * @s1: First buffer
283  * @s2: Second buffer
284  * @n: Maximum numbers of octets to compare
285  * Returns: An integer less than, equal to, or greater than zero if s1 is
286  * found to be less than, to match, or be greater than s2. Only first n
287  * characters will be compared.
288  */
289 int os_memcmp(const void *s1, const void *s2, size_t n);
290 
291 /**
292  * os_strdup - Duplicate a string
293  * @s: Source string
294  * Returns: Allocated buffer with the string copied into it or %NULL on failure
295  *
296  * Caller is responsible for freeing the returned buffer with os_free().
297  */
298 char * os_strdup(const char *s);
299 
300 /**
301  * os_strlen - Calculate the length of a string
302  * @s: '\0' terminated string
303  * Returns: Number of characters in s (not counting the '\0' terminator)
304  */
305 size_t os_strlen(const char *s);
306 
307 /**
308  * os_strcasecmp - Compare two strings ignoring case
309  * @s1: First string
310  * @s2: Second string
311  * Returns: An integer less than, equal to, or greater than zero if s1 is
312  * found to be less than, to match, or be greatred than s2
313  */
314 int os_strcasecmp(const char *s1, const char *s2);
315 
316 /**
317  * os_strncasecmp - Compare two strings ignoring case
318  * @s1: First string
319  * @s2: Second string
320  * @n: Maximum numbers of characters to compare
321  * Returns: An integer less than, equal to, or greater than zero if s1 is
322  * found to be less than, to match, or be greater than s2. Only first n
323  * characters will be compared.
324  */
325 int os_strncasecmp(const char *s1, const char *s2, size_t n);
326 
327 /**
328  * os_strchr - Locate the first occurrence of a character in string
329  * @s: String
330  * @c: Character to search for
331  * Returns: Pointer to the matched character or %NULL if not found
332  */
333 char * os_strchr(const char *s, int c);
334 
335 /**
336  * os_strrchr - Locate the last occurrence of a character in string
337  * @s: String
338  * @c: Character to search for
339  * Returns: Pointer to the matched character or %NULL if not found
340  */
341 char * os_strrchr(const char *s, int c);
342 
343 /**
344  * os_strcmp - Compare two strings
345  * @s1: First string
346  * @s2: Second string
347  * Returns: An integer less than, equal to, or greater than zero if s1 is
348  * found to be less than, to match, or be greatred than s2
349  */
350 int os_strcmp(const char *s1, const char *s2);
351 
352 /**
353  * os_strncmp - Compare two strings
354  * @s1: First string
355  * @s2: Second string
356  * @n: Maximum numbers of characters to compare
357  * Returns: An integer less than, equal to, or greater than zero if s1 is
358  * found to be less than, to match, or be greater than s2. Only first n
359  * characters will be compared.
360  */
361 int os_strncmp(const char *s1, const char *s2, size_t n);
362 
363 /**
364  * os_strncpy - Copy a string
365  * @dest: Destination
366  * @src: Source
367  * @n: Maximum number of characters to copy
368  * Returns: dest
369  */
370 char * os_strncpy(char *dest, const char *src, size_t n);
371 
372 /**
373  * os_strstr - Locate a substring
374  * @haystack: String (haystack) to search from
375  * @needle: Needle to search from haystack
376  * Returns: Pointer to the beginning of the substring or %NULL if not found
377  */
378 char * os_strstr(const char *haystack, const char *needle);
379 
380 /**
381  * os_snprintf - Print to a memory buffer
382  * @str: Memory buffer to print into
383  * @size: Maximum length of the str buffer
384  * @format: printf format
385  * Returns: Number of characters printed (not including trailing '\0').
386  *
387  * If the output buffer is truncated, number of characters which would have
388  * been written is returned. Since some C libraries return -1 in such a case,
389  * the caller must be prepared on that value, too, to indicate truncation.
390  *
391  * Note: Some C library implementations of snprintf() may not guarantee null
392  * termination in case the output is truncated. The OS wrapper function of
393  * os_snprintf() should provide this guarantee, i.e., to null terminate the
394  * output buffer if a C library version of the function is used and if that
395  * function does not guarantee null termination.
396  *
397  * If the target system does not include snprintf(), see, e.g.,
398  * http://www.ijs.si/software/snprintf/ for an example of a portable
399  * implementation of snprintf.
400  */
401 int os_snprintf(char *str, size_t size, const char *format, ...);
402 
403 #else /* OS_NO_C_LIB_DEFINES */
404 
405 #ifdef WPA_TRACE
406 void * os_malloc(size_t size);
407 void * os_realloc(void *ptr, size_t size);
408 void os_free(void *ptr);
409 char * os_strdup(const char *s);
410 #else /* WPA_TRACE */
411 #ifndef os_malloc
412 #define os_malloc(s) malloc((s))
413 #endif
414 #ifndef os_realloc
415 #define os_realloc(p, s) realloc((p), (s))
416 #endif
417 #ifndef os_free
418 #define os_free(p) free((p))
419 #endif
420 #ifndef os_strdup
421 #ifdef _MSC_VER
422 #define os_strdup(s) _strdup(s)
423 #else
424 #define os_strdup(s) strdup(s)
425 #endif
426 #endif
427 #endif /* WPA_TRACE */
428 
429 #ifndef os_memcpy
430 #define os_memcpy(d, s, n) memcpy((d), (s), (n))
431 #endif
432 #ifndef os_memmove
433 #define os_memmove(d, s, n) memmove((d), (s), (n))
434 #endif
435 #ifndef os_memset
436 #define os_memset(s, c, n) memset(s, c, n)
437 #endif
438 #ifndef os_memcmp
439 #define os_memcmp(s1, s2, n) memcmp((s1), (s2), (n))
440 #endif
441 
442 #ifndef os_strlen
443 #define os_strlen(s) strlen(s)
444 #endif
445 #ifndef os_strcasecmp
446 #ifdef _MSC_VER
447 #define os_strcasecmp(s1, s2) _stricmp((s1), (s2))
448 #else
449 #define os_strcasecmp(s1, s2) strcasecmp((s1), (s2))
450 #endif
451 #endif
452 #ifndef os_strncasecmp
453 #ifdef _MSC_VER
454 #define os_strncasecmp(s1, s2, n) _strnicmp((s1), (s2), (n))
455 #else
456 #define os_strncasecmp(s1, s2, n) strncasecmp((s1), (s2), (n))
457 #endif
458 #endif
459 #ifndef os_strchr
460 #define os_strchr(s, c) strchr((s), (c))
461 #endif
462 #ifndef os_strcmp
463 #define os_strcmp(s1, s2) strcmp((s1), (s2))
464 #endif
465 #ifndef os_strncmp
466 #define os_strncmp(s1, s2, n) strncmp((s1), (s2), (n))
467 #endif
468 #ifndef os_strncpy
469 #define os_strncpy(d, s, n) strncpy((d), (s), (n))
470 #endif
471 #ifndef os_strrchr
472 #define os_strrchr(s, c) strrchr((s), (c))
473 #endif
474 #ifndef os_strstr
475 #define os_strstr(h, n) strstr((h), (n))
476 #endif
477 
478 #ifndef os_snprintf
479 #ifdef _MSC_VER
480 #define os_snprintf _snprintf
481 #else
482 #define os_snprintf snprintf
483 #endif
484 #endif
485 
486 #endif /* OS_NO_C_LIB_DEFINES */
487 
488 
489 static inline void * os_realloc_array(void *ptr, size_t nmemb, size_t size)
490 {
491 	if (size && nmemb > (~(size_t) 0) / size)
492 		return NULL;
493 	return os_realloc(ptr, nmemb * size);
494 }
495 
496 
497 /**
498  * os_strlcpy - Copy a string with size bound and NUL-termination
499  * @dest: Destination
500  * @src: Source
501  * @siz: Size of the target buffer
502  * Returns: Total length of the target string (length of src) (not including
503  * NUL-termination)
504  *
505  * This function matches in behavior with the strlcpy(3) function in OpenBSD.
506  */
507 size_t os_strlcpy(char *dest, const char *src, size_t siz);
508 
509 
510 #ifdef OS_REJECT_C_LIB_FUNCTIONS
511 #define malloc OS_DO_NOT_USE_malloc
512 #define realloc OS_DO_NOT_USE_realloc
513 #define free OS_DO_NOT_USE_free
514 #define memcpy OS_DO_NOT_USE_memcpy
515 #define memmove OS_DO_NOT_USE_memmove
516 #define memset OS_DO_NOT_USE_memset
517 #define memcmp OS_DO_NOT_USE_memcmp
518 #undef strdup
519 #define strdup OS_DO_NOT_USE_strdup
520 #define strlen OS_DO_NOT_USE_strlen
521 #define strcasecmp OS_DO_NOT_USE_strcasecmp
522 #define strncasecmp OS_DO_NOT_USE_strncasecmp
523 #undef strchr
524 #define strchr OS_DO_NOT_USE_strchr
525 #undef strcmp
526 #define strcmp OS_DO_NOT_USE_strcmp
527 #undef strncmp
528 #define strncmp OS_DO_NOT_USE_strncmp
529 #undef strncpy
530 #define strncpy OS_DO_NOT_USE_strncpy
531 #define strrchr OS_DO_NOT_USE_strrchr
532 #define strstr OS_DO_NOT_USE_strstr
533 #undef snprintf
534 #define snprintf OS_DO_NOT_USE_snprintf
535 
536 #define strcpy OS_DO_NOT_USE_strcpy
537 #endif /* OS_REJECT_C_LIB_FUNCTIONS */
538 
539 #endif /* OS_H */
540