xref: /netbsd-src/external/bsd/wpa/dist/src/utils/os.h (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*
2  * OS specific functions
3  * Copyright (c) 2005-2009, Jouni Malinen <j@w1.fi>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * Alternatively, this software may be distributed under the terms of BSD
10  * license.
11  *
12  * See README and COPYING for more details.
13  */
14 
15 #ifndef OS_H
16 #define OS_H
17 
18 typedef time_t os_time_t;
19 
20 /**
21  * os_sleep - Sleep (sec, usec)
22  * @sec: Number of seconds to sleep
23  * @usec: Number of microseconds to sleep
24  */
25 void os_sleep(os_time_t sec, os_time_t usec);
26 
27 struct os_time {
28 	os_time_t sec;
29 	os_time_t usec;
30 };
31 
32 /**
33  * os_get_time - Get current time (sec, usec)
34  * @t: Pointer to buffer for the time
35  * Returns: 0 on success, -1 on failure
36  */
37 int os_get_time(struct os_time *t);
38 
39 
40 /* Helper macros for handling struct os_time */
41 
42 #define os_time_before(a, b) \
43 	((a)->sec < (b)->sec || \
44 	 ((a)->sec == (b)->sec && (a)->usec < (b)->usec))
45 
46 #define os_time_sub(a, b, res) do { \
47 	(res)->sec = (a)->sec - (b)->sec; \
48 	(res)->usec = (a)->usec - (b)->usec; \
49 	if ((res)->usec < 0) { \
50 		(res)->sec--; \
51 		(res)->usec += 1000000; \
52 	} \
53 } while (0)
54 
55 /**
56  * os_mktime - Convert broken-down time into seconds since 1970-01-01
57  * @year: Four digit year
58  * @month: Month (1 .. 12)
59  * @day: Day of month (1 .. 31)
60  * @hour: Hour (0 .. 23)
61  * @min: Minute (0 .. 59)
62  * @sec: Second (0 .. 60)
63  * @t: Buffer for returning calendar time representation (seconds since
64  * 1970-01-01 00:00:00)
65  * Returns: 0 on success, -1 on failure
66  *
67  * Note: The result is in seconds from Epoch, i.e., in UTC, not in local time
68  * which is used by POSIX mktime().
69  */
70 int os_mktime(int year, int month, int day, int hour, int min, int sec,
71 	      os_time_t *t);
72 
73 struct os_tm {
74 	int sec; /* 0..59 or 60 for leap seconds */
75 	int min; /* 0..59 */
76 	int hour; /* 0..23 */
77 	int day; /* 1..31 */
78 	int month; /* 1..12 */
79 	int year; /* Four digit year */
80 };
81 
82 int os_gmtime(os_time_t t, struct os_tm *tm);
83 
84 /**
85  * os_daemonize - Run in the background (detach from the controlling terminal)
86  * @pid_file: File name to write the process ID to or %NULL to skip this
87  * Returns: 0 on success, -1 on failure
88  */
89 int os_daemonize(const char *pid_file);
90 
91 /**
92  * os_daemonize_terminate - Stop running in the background (remove pid file)
93  * @pid_file: File name to write the process ID to or %NULL to skip this
94  */
95 void os_daemonize_terminate(const char *pid_file);
96 
97 /**
98  * os_get_random - Get cryptographically strong pseudo random data
99  * @buf: Buffer for pseudo random data
100  * @len: Length of the buffer
101  * Returns: 0 on success, -1 on failure
102  */
103 int os_get_random(unsigned char *buf, size_t len);
104 
105 /**
106  * os_random - Get pseudo random value (not necessarily very strong)
107  * Returns: Pseudo random value
108  */
109 unsigned long os_random(void);
110 
111 /**
112  * os_rel2abs_path - Get an absolute path for a file
113  * @rel_path: Relative path to a file
114  * Returns: Absolute path for the file or %NULL on failure
115  *
116  * This function tries to convert a relative path of a file to an absolute path
117  * in order for the file to be found even if current working directory has
118  * changed. The returned value is allocated and caller is responsible for
119  * freeing it. It is acceptable to just return the same path in an allocated
120  * buffer, e.g., return strdup(rel_path). This function is only used to find
121  * configuration files when os_daemonize() may have changed the current working
122  * directory and relative path would be pointing to a different location.
123  */
124 char * os_rel2abs_path(const char *rel_path);
125 
126 /**
127  * os_program_init - Program initialization (called at start)
128  * Returns: 0 on success, -1 on failure
129  *
130  * This function is called when a programs starts. If there are any OS specific
131  * processing that is needed, it can be placed here. It is also acceptable to
132  * just return 0 if not special processing is needed.
133  */
134 int os_program_init(void);
135 
136 /**
137  * os_program_deinit - Program deinitialization (called just before exit)
138  *
139  * This function is called just before a program exists. If there are any OS
140  * specific processing, e.g., freeing resourced allocated in os_program_init(),
141  * it should be done here. It is also acceptable for this function to do
142  * nothing.
143  */
144 void os_program_deinit(void);
145 
146 /**
147  * os_setenv - Set environment variable
148  * @name: Name of the variable
149  * @value: Value to set to the variable
150  * @overwrite: Whether existing variable should be overwritten
151  * Returns: 0 on success, -1 on error
152  *
153  * This function is only used for wpa_cli action scripts. OS wrapper does not
154  * need to implement this if such functionality is not needed.
155  */
156 int os_setenv(const char *name, const char *value, int overwrite);
157 
158 /**
159  * os_unsetenv - Delete environent variable
160  * @name: Name of the variable
161  * Returns: 0 on success, -1 on error
162  *
163  * This function is only used for wpa_cli action scripts. OS wrapper does not
164  * need to implement this if such functionality is not needed.
165  */
166 int os_unsetenv(const char *name);
167 
168 /**
169  * os_readfile - Read a file to an allocated memory buffer
170  * @name: Name of the file to read
171  * @len: For returning the length of the allocated buffer
172  * Returns: Pointer to the allocated buffer or %NULL on failure
173  *
174  * This function allocates memory and reads the given file to this buffer. Both
175  * binary and text files can be read with this function. The caller is
176  * responsible for freeing the returned buffer with os_free().
177  */
178 char * os_readfile(const char *name, size_t *len);
179 
180 /**
181  * os_zalloc - Allocate and zero memory
182  * @size: Number of bytes to allocate
183  * Returns: Pointer to allocated and zeroed memory or %NULL on failure
184  *
185  * Caller is responsible for freeing the returned buffer with os_free().
186  */
187 void * os_zalloc(size_t size);
188 
189 
190 /*
191  * The following functions are wrapper for standard ANSI C or POSIX functions.
192  * By default, they are just defined to use the standard function name and no
193  * os_*.c implementation is needed for them. This avoids extra function calls
194  * by allowing the C pre-processor take care of the function name mapping.
195  *
196  * If the target system uses a C library that does not provide these functions,
197  * build_config.h can be used to define the wrappers to use a different
198  * function name. This can be done on function-by-function basis since the
199  * defines here are only used if build_config.h does not define the os_* name.
200  * If needed, os_*.c file can be used to implement the functions that are not
201  * included in the C library on the target system. Alternatively,
202  * OS_NO_C_LIB_DEFINES can be defined to skip all defines here in which case
203  * these functions need to be implemented in os_*.c file for the target system.
204  */
205 
206 #ifdef OS_NO_C_LIB_DEFINES
207 
208 /**
209  * os_malloc - Allocate dynamic memory
210  * @size: Size of the buffer to allocate
211  * Returns: Allocated buffer or %NULL on failure
212  *
213  * Caller is responsible for freeing the returned buffer with os_free().
214  */
215 void * os_malloc(size_t size);
216 
217 /**
218  * os_realloc - Re-allocate dynamic memory
219  * @ptr: Old buffer from os_malloc() or os_realloc()
220  * @size: Size of the new buffer
221  * Returns: Allocated buffer or %NULL on failure
222  *
223  * Caller is responsible for freeing the returned buffer with os_free().
224  * If re-allocation fails, %NULL is returned and the original buffer (ptr) is
225  * not freed and caller is still responsible for freeing it.
226  */
227 void * os_realloc(void *ptr, size_t size);
228 
229 /**
230  * os_free - Free dynamic memory
231  * @ptr: Old buffer from os_malloc() or os_realloc(); can be %NULL
232  */
233 void os_free(void *ptr);
234 
235 /**
236  * os_memcpy - Copy memory area
237  * @dest: Destination
238  * @src: Source
239  * @n: Number of bytes to copy
240  * Returns: dest
241  *
242  * The memory areas src and dst must not overlap. os_memmove() can be used with
243  * overlapping memory.
244  */
245 void * os_memcpy(void *dest, const void *src, size_t n);
246 
247 /**
248  * os_memmove - Copy memory area
249  * @dest: Destination
250  * @src: Source
251  * @n: Number of bytes to copy
252  * Returns: dest
253  *
254  * The memory areas src and dst may overlap.
255  */
256 void * os_memmove(void *dest, const void *src, size_t n);
257 
258 /**
259  * os_memset - Fill memory with a constant byte
260  * @s: Memory area to be filled
261  * @c: Constant byte
262  * @n: Number of bytes started from s to fill with c
263  * Returns: s
264  */
265 void * os_memset(void *s, int c, size_t n);
266 
267 /**
268  * os_memcmp - Compare memory areas
269  * @s1: First buffer
270  * @s2: Second buffer
271  * @n: Maximum numbers of octets to compare
272  * Returns: An integer less than, equal to, or greater than zero if s1 is
273  * found to be less than, to match, or be greater than s2. Only first n
274  * characters will be compared.
275  */
276 int os_memcmp(const void *s1, const void *s2, size_t n);
277 
278 /**
279  * os_strdup - Duplicate a string
280  * @s: Source string
281  * Returns: Allocated buffer with the string copied into it or %NULL on failure
282  *
283  * Caller is responsible for freeing the returned buffer with os_free().
284  */
285 char * os_strdup(const char *s);
286 
287 /**
288  * os_strlen - Calculate the length of a string
289  * @s: '\0' terminated string
290  * Returns: Number of characters in s (not counting the '\0' terminator)
291  */
292 size_t os_strlen(const char *s);
293 
294 /**
295  * os_strcasecmp - Compare two strings ignoring case
296  * @s1: First string
297  * @s2: Second string
298  * Returns: An integer less than, equal to, or greater than zero if s1 is
299  * found to be less than, to match, or be greatred than s2
300  */
301 int os_strcasecmp(const char *s1, const char *s2);
302 
303 /**
304  * os_strncasecmp - Compare two strings ignoring case
305  * @s1: First string
306  * @s2: Second string
307  * @n: Maximum numbers of characters to compare
308  * Returns: An integer less than, equal to, or greater than zero if s1 is
309  * found to be less than, to match, or be greater than s2. Only first n
310  * characters will be compared.
311  */
312 int os_strncasecmp(const char *s1, const char *s2, size_t n);
313 
314 /**
315  * os_strchr - Locate the first occurrence of a character in string
316  * @s: String
317  * @c: Character to search for
318  * Returns: Pointer to the matched character or %NULL if not found
319  */
320 char * os_strchr(const char *s, int c);
321 
322 /**
323  * os_strrchr - Locate the last occurrence of a character in string
324  * @s: String
325  * @c: Character to search for
326  * Returns: Pointer to the matched character or %NULL if not found
327  */
328 char * os_strrchr(const char *s, int c);
329 
330 /**
331  * os_strcmp - Compare two strings
332  * @s1: First string
333  * @s2: Second string
334  * Returns: An integer less than, equal to, or greater than zero if s1 is
335  * found to be less than, to match, or be greatred than s2
336  */
337 int os_strcmp(const char *s1, const char *s2);
338 
339 /**
340  * os_strncmp - Compare two strings
341  * @s1: First string
342  * @s2: Second string
343  * @n: Maximum numbers of characters to compare
344  * Returns: An integer less than, equal to, or greater than zero if s1 is
345  * found to be less than, to match, or be greater than s2. Only first n
346  * characters will be compared.
347  */
348 int os_strncmp(const char *s1, const char *s2, size_t n);
349 
350 /**
351  * os_strncpy - Copy a string
352  * @dest: Destination
353  * @src: Source
354  * @n: Maximum number of characters to copy
355  * Returns: dest
356  */
357 char * os_strncpy(char *dest, const char *src, size_t n);
358 
359 /**
360  * os_strstr - Locate a substring
361  * @haystack: String (haystack) to search from
362  * @needle: Needle to search from haystack
363  * Returns: Pointer to the beginning of the substring or %NULL if not found
364  */
365 char * os_strstr(const char *haystack, const char *needle);
366 
367 /**
368  * os_snprintf - Print to a memory buffer
369  * @str: Memory buffer to print into
370  * @size: Maximum length of the str buffer
371  * @format: printf format
372  * Returns: Number of characters printed (not including trailing '\0').
373  *
374  * If the output buffer is truncated, number of characters which would have
375  * been written is returned. Since some C libraries return -1 in such a case,
376  * the caller must be prepared on that value, too, to indicate truncation.
377  *
378  * Note: Some C library implementations of snprintf() may not guarantee null
379  * termination in case the output is truncated. The OS wrapper function of
380  * os_snprintf() should provide this guarantee, i.e., to null terminate the
381  * output buffer if a C library version of the function is used and if that
382  * function does not guarantee null termination.
383  *
384  * If the target system does not include snprintf(), see, e.g.,
385  * http://www.ijs.si/software/snprintf/ for an example of a portable
386  * implementation of snprintf.
387  */
388 int os_snprintf(char *str, size_t size, const char *format, ...);
389 
390 #else /* OS_NO_C_LIB_DEFINES */
391 
392 #ifdef WPA_TRACE
393 void * os_malloc(size_t size);
394 void * os_realloc(void *ptr, size_t size);
395 void os_free(void *ptr);
396 char * os_strdup(const char *s);
397 #else /* WPA_TRACE */
398 #ifndef os_malloc
399 #define os_malloc(s) malloc((s))
400 #endif
401 #ifndef os_realloc
402 #define os_realloc(p, s) realloc((p), (s))
403 #endif
404 #ifndef os_free
405 #define os_free(p) free((p))
406 #endif
407 #ifndef os_strdup
408 #ifdef _MSC_VER
409 #define os_strdup(s) _strdup(s)
410 #else
411 #define os_strdup(s) strdup(s)
412 #endif
413 #endif
414 #endif /* WPA_TRACE */
415 
416 #ifndef os_memcpy
417 #define os_memcpy(d, s, n) memcpy((d), (s), (n))
418 #endif
419 #ifndef os_memmove
420 #define os_memmove(d, s, n) memmove((d), (s), (n))
421 #endif
422 #ifndef os_memset
423 #define os_memset(s, c, n) memset(s, c, n)
424 #endif
425 #ifndef os_memcmp
426 #define os_memcmp(s1, s2, n) memcmp((s1), (s2), (n))
427 #endif
428 
429 #ifndef os_strlen
430 #define os_strlen(s) strlen(s)
431 #endif
432 #ifndef os_strcasecmp
433 #ifdef _MSC_VER
434 #define os_strcasecmp(s1, s2) _stricmp((s1), (s2))
435 #else
436 #define os_strcasecmp(s1, s2) strcasecmp((s1), (s2))
437 #endif
438 #endif
439 #ifndef os_strncasecmp
440 #ifdef _MSC_VER
441 #define os_strncasecmp(s1, s2, n) _strnicmp((s1), (s2), (n))
442 #else
443 #define os_strncasecmp(s1, s2, n) strncasecmp((s1), (s2), (n))
444 #endif
445 #endif
446 #ifndef os_strchr
447 #define os_strchr(s, c) strchr((s), (c))
448 #endif
449 #ifndef os_strcmp
450 #define os_strcmp(s1, s2) strcmp((s1), (s2))
451 #endif
452 #ifndef os_strncmp
453 #define os_strncmp(s1, s2, n) strncmp((s1), (s2), (n))
454 #endif
455 #ifndef os_strncpy
456 #define os_strncpy(d, s, n) strncpy((d), (s), (n))
457 #endif
458 #ifndef os_strrchr
459 #define os_strrchr(s, c) strrchr((s), (c))
460 #endif
461 #ifndef os_strstr
462 #define os_strstr(h, n) strstr((h), (n))
463 #endif
464 
465 #ifndef os_snprintf
466 #ifdef _MSC_VER
467 #define os_snprintf _snprintf
468 #else
469 #define os_snprintf snprintf
470 #endif
471 #endif
472 
473 #endif /* OS_NO_C_LIB_DEFINES */
474 
475 
476 /**
477  * os_strlcpy - Copy a string with size bound and NUL-termination
478  * @dest: Destination
479  * @src: Source
480  * @siz: Size of the target buffer
481  * Returns: Total length of the target string (length of src) (not including
482  * NUL-termination)
483  *
484  * This function matches in behavior with the strlcpy(3) function in OpenBSD.
485  */
486 size_t os_strlcpy(char *dest, const char *src, size_t siz);
487 
488 
489 #ifdef OS_REJECT_C_LIB_FUNCTIONS
490 #define malloc OS_DO_NOT_USE_malloc
491 #define realloc OS_DO_NOT_USE_realloc
492 #define free OS_DO_NOT_USE_free
493 #define memcpy OS_DO_NOT_USE_memcpy
494 #define memmove OS_DO_NOT_USE_memmove
495 #define memset OS_DO_NOT_USE_memset
496 #define memcmp OS_DO_NOT_USE_memcmp
497 #undef strdup
498 #define strdup OS_DO_NOT_USE_strdup
499 #define strlen OS_DO_NOT_USE_strlen
500 #define strcasecmp OS_DO_NOT_USE_strcasecmp
501 #define strncasecmp OS_DO_NOT_USE_strncasecmp
502 #undef strchr
503 #define strchr OS_DO_NOT_USE_strchr
504 #undef strcmp
505 #define strcmp OS_DO_NOT_USE_strcmp
506 #undef strncmp
507 #define strncmp OS_DO_NOT_USE_strncmp
508 #undef strncpy
509 #define strncpy OS_DO_NOT_USE_strncpy
510 #define strrchr OS_DO_NOT_USE_strrchr
511 #define strstr OS_DO_NOT_USE_strstr
512 #undef snprintf
513 #define snprintf OS_DO_NOT_USE_snprintf
514 
515 #define strcpy OS_DO_NOT_USE_strcpy
516 #endif /* OS_REJECT_C_LIB_FUNCTIONS */
517 
518 #endif /* OS_H */
519