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
12typedef 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 */
19void os_sleep(os_time_t sec, os_time_t usec);
20
21struct 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 */
31int 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 */
64int os_mktime(int year, int month, int day, int hour, int min, int sec,
65	      os_time_t *t);
66
67struct 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
76int 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 */
83int 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 */
89void 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 */
97int 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 */
103unsigned 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 */
118char * 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 */
128int 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 */
138void 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 */
150int 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 */
160int 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 */
172char * 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 */
181void * os_zalloc(size_t size);
182
183
184/*
185 * The following functions are wrapper for standard ANSI C or POSIX functions.
186 * By default, they are just defined to use the standard function name and no
187 * os_*.c implementation is needed for them. This avoids extra function calls
188 * by allowing the C pre-processor take care of the function name mapping.
189 *
190 * If the target system uses a C library that does not provide these functions,
191 * build_config.h can be used to define the wrappers to use a different
192 * function name. This can be done on function-by-function basis since the
193 * defines here are only used if build_config.h does not define the os_* name.
194 * If needed, os_*.c file can be used to implement the functions that are not
195 * included in the C library on the target system. Alternatively,
196 * OS_NO_C_LIB_DEFINES can be defined to skip all defines here in which case
197 * these functions need to be implemented in os_*.c file for the target system.
198 */
199
200#ifdef OS_NO_C_LIB_DEFINES
201
202/**
203 * os_malloc - Allocate dynamic memory
204 * @size: Size of the buffer to allocate
205 * Returns: Allocated buffer or %NULL on failure
206 *
207 * Caller is responsible for freeing the returned buffer with os_free().
208 */
209void * os_malloc(size_t size);
210
211/**
212 * os_realloc - Re-allocate dynamic memory
213 * @ptr: Old buffer from os_malloc() or os_realloc()
214 * @size: Size of the new buffer
215 * Returns: Allocated buffer or %NULL on failure
216 *
217 * Caller is responsible for freeing the returned buffer with os_free().
218 * If re-allocation fails, %NULL is returned and the original buffer (ptr) is
219 * not freed and caller is still responsible for freeing it.
220 */
221void * os_realloc(void *ptr, size_t size);
222
223/**
224 * os_free - Free dynamic memory
225 * @ptr: Old buffer from os_malloc() or os_realloc(); can be %NULL
226 */
227void os_free(void *ptr);
228
229/**
230 * os_memcpy - Copy memory area
231 * @dest: Destination
232 * @src: Source
233 * @n: Number of bytes to copy
234 * Returns: dest
235 *
236 * The memory areas src and dst must not overlap. os_memmove() can be used with
237 * overlapping memory.
238 */
239void * os_memcpy(void *dest, const void *src, size_t n);
240
241/**
242 * os_memmove - Copy memory area
243 * @dest: Destination
244 * @src: Source
245 * @n: Number of bytes to copy
246 * Returns: dest
247 *
248 * The memory areas src and dst may overlap.
249 */
250void * os_memmove(void *dest, const void *src, size_t n);
251
252/**
253 * os_memset - Fill memory with a constant byte
254 * @s: Memory area to be filled
255 * @c: Constant byte
256 * @n: Number of bytes started from s to fill with c
257 * Returns: s
258 */
259void * os_memset(void *s, int c, size_t n);
260
261/**
262 * os_memcmp - Compare memory areas
263 * @s1: First buffer
264 * @s2: Second buffer
265 * @n: Maximum numbers of octets to compare
266 * Returns: An integer less than, equal to, or greater than zero if s1 is
267 * found to be less than, to match, or be greater than s2. Only first n
268 * characters will be compared.
269 */
270int os_memcmp(const void *s1, const void *s2, size_t n);
271
272/**
273 * os_strdup - Duplicate a string
274 * @s: Source string
275 * Returns: Allocated buffer with the string copied into it or %NULL on failure
276 *
277 * Caller is responsible for freeing the returned buffer with os_free().
278 */
279char * os_strdup(const char *s);
280
281/**
282 * os_strlen - Calculate the length of a string
283 * @s: '\0' terminated string
284 * Returns: Number of characters in s (not counting the '\0' terminator)
285 */
286size_t os_strlen(const char *s);
287
288/**
289 * os_strcasecmp - Compare two strings ignoring case
290 * @s1: First string
291 * @s2: Second string
292 * Returns: An integer less than, equal to, or greater than zero if s1 is
293 * found to be less than, to match, or be greatred than s2
294 */
295int os_strcasecmp(const char *s1, const char *s2);
296
297/**
298 * os_strncasecmp - Compare two strings ignoring case
299 * @s1: First string
300 * @s2: Second string
301 * @n: Maximum numbers of characters to compare
302 * Returns: An integer less than, equal to, or greater than zero if s1 is
303 * found to be less than, to match, or be greater than s2. Only first n
304 * characters will be compared.
305 */
306int os_strncasecmp(const char *s1, const char *s2, size_t n);
307
308/**
309 * os_strchr - Locate the first occurrence of a character in string
310 * @s: String
311 * @c: Character to search for
312 * Returns: Pointer to the matched character or %NULL if not found
313 */
314char * os_strchr(const char *s, int c);
315
316/**
317 * os_strrchr - Locate the last occurrence of a character in string
318 * @s: String
319 * @c: Character to search for
320 * Returns: Pointer to the matched character or %NULL if not found
321 */
322char * os_strrchr(const char *s, int c);
323
324/**
325 * os_strcmp - Compare two strings
326 * @s1: First string
327 * @s2: Second string
328 * Returns: An integer less than, equal to, or greater than zero if s1 is
329 * found to be less than, to match, or be greatred than s2
330 */
331int os_strcmp(const char *s1, const char *s2);
332
333/**
334 * os_strncmp - Compare two strings
335 * @s1: First string
336 * @s2: Second string
337 * @n: Maximum numbers of characters to compare
338 * Returns: An integer less than, equal to, or greater than zero if s1 is
339 * found to be less than, to match, or be greater than s2. Only first n
340 * characters will be compared.
341 */
342int os_strncmp(const char *s1, const char *s2, size_t n);
343
344/**
345 * os_strncpy - Copy a string
346 * @dest: Destination
347 * @src: Source
348 * @n: Maximum number of characters to copy
349 * Returns: dest
350 */
351char * os_strncpy(char *dest, const char *src, size_t n);
352
353/**
354 * os_strstr - Locate a substring
355 * @haystack: String (haystack) to search from
356 * @needle: Needle to search from haystack
357 * Returns: Pointer to the beginning of the substring or %NULL if not found
358 */
359char * os_strstr(const char *haystack, const char *needle);
360
361/**
362 * os_snprintf - Print to a memory buffer
363 * @str: Memory buffer to print into
364 * @size: Maximum length of the str buffer
365 * @format: printf format
366 * Returns: Number of characters printed (not including trailing '\0').
367 *
368 * If the output buffer is truncated, number of characters which would have
369 * been written is returned. Since some C libraries return -1 in such a case,
370 * the caller must be prepared on that value, too, to indicate truncation.
371 *
372 * Note: Some C library implementations of snprintf() may not guarantee null
373 * termination in case the output is truncated. The OS wrapper function of
374 * os_snprintf() should provide this guarantee, i.e., to null terminate the
375 * output buffer if a C library version of the function is used and if that
376 * function does not guarantee null termination.
377 *
378 * If the target system does not include snprintf(), see, e.g.,
379 * http://www.ijs.si/software/snprintf/ for an example of a portable
380 * implementation of snprintf.
381 */
382int os_snprintf(char *str, size_t size, const char *format, ...);
383
384#else /* OS_NO_C_LIB_DEFINES */
385
386#ifdef WPA_TRACE
387void * os_malloc(size_t size);
388void * os_realloc(void *ptr, size_t size);
389void os_free(void *ptr);
390char * os_strdup(const char *s);
391#else /* WPA_TRACE */
392#ifndef os_malloc
393#define os_malloc(s) malloc((s))
394#endif
395#ifndef os_realloc
396#define os_realloc(p, s) realloc((p), (s))
397#endif
398#ifndef os_free
399#define os_free(p) free((p))
400#endif
401#ifndef os_strdup
402#ifdef _MSC_VER
403#define os_strdup(s) _strdup(s)
404#else
405#define os_strdup(s) strdup(s)
406#endif
407#endif
408#endif /* WPA_TRACE */
409
410#ifndef os_memcpy
411#define os_memcpy(d, s, n) memcpy((d), (s), (n))
412#endif
413#ifndef os_memmove
414#define os_memmove(d, s, n) memmove((d), (s), (n))
415#endif
416#ifndef os_memset
417#define os_memset(s, c, n) memset(s, c, n)
418#endif
419#ifndef os_memcmp
420#define os_memcmp(s1, s2, n) memcmp((s1), (s2), (n))
421#endif
422
423#ifndef os_strlen
424#define os_strlen(s) strlen(s)
425#endif
426#ifndef os_strcasecmp
427#ifdef _MSC_VER
428#define os_strcasecmp(s1, s2) _stricmp((s1), (s2))
429#else
430#define os_strcasecmp(s1, s2) strcasecmp((s1), (s2))
431#endif
432#endif
433#ifndef os_strncasecmp
434#ifdef _MSC_VER
435#define os_strncasecmp(s1, s2, n) _strnicmp((s1), (s2), (n))
436#else
437#define os_strncasecmp(s1, s2, n) strncasecmp((s1), (s2), (n))
438#endif
439#endif
440#ifndef os_strchr
441#define os_strchr(s, c) strchr((s), (c))
442#endif
443#ifndef os_strcmp
444#define os_strcmp(s1, s2) strcmp((s1), (s2))
445#endif
446#ifndef os_strncmp
447#define os_strncmp(s1, s2, n) strncmp((s1), (s2), (n))
448#endif
449#ifndef os_strncpy
450#define os_strncpy(d, s, n) strncpy((d), (s), (n))
451#endif
452#ifndef os_strrchr
453#define os_strrchr(s, c) strrchr((s), (c))
454#endif
455#ifndef os_strstr
456#define os_strstr(h, n) strstr((h), (n))
457#endif
458
459#ifndef os_snprintf
460#ifdef _MSC_VER
461#define os_snprintf _snprintf
462#else
463#define os_snprintf snprintf
464#endif
465#endif
466
467#endif /* OS_NO_C_LIB_DEFINES */
468
469
470/**
471 * os_strlcpy - Copy a string with size bound and NUL-termination
472 * @dest: Destination
473 * @src: Source
474 * @siz: Size of the target buffer
475 * Returns: Total length of the target string (length of src) (not including
476 * NUL-termination)
477 *
478 * This function matches in behavior with the strlcpy(3) function in OpenBSD.
479 */
480size_t os_strlcpy(char *dest, const char *src, size_t siz);
481
482
483#ifdef OS_REJECT_C_LIB_FUNCTIONS
484#define malloc OS_DO_NOT_USE_malloc
485#define realloc OS_DO_NOT_USE_realloc
486#define free OS_DO_NOT_USE_free
487#define memcpy OS_DO_NOT_USE_memcpy
488#define memmove OS_DO_NOT_USE_memmove
489#define memset OS_DO_NOT_USE_memset
490#define memcmp OS_DO_NOT_USE_memcmp
491#undef strdup
492#define strdup OS_DO_NOT_USE_strdup
493#define strlen OS_DO_NOT_USE_strlen
494#define strcasecmp OS_DO_NOT_USE_strcasecmp
495#define strncasecmp OS_DO_NOT_USE_strncasecmp
496#undef strchr
497#define strchr OS_DO_NOT_USE_strchr
498#undef strcmp
499#define strcmp OS_DO_NOT_USE_strcmp
500#undef strncmp
501#define strncmp OS_DO_NOT_USE_strncmp
502#undef strncpy
503#define strncpy OS_DO_NOT_USE_strncpy
504#define strrchr OS_DO_NOT_USE_strrchr
505#define strstr OS_DO_NOT_USE_strstr
506#undef snprintf
507#define snprintf OS_DO_NOT_USE_snprintf
508
509#define strcpy OS_DO_NOT_USE_strcpy
510#endif /* OS_REJECT_C_LIB_FUNCTIONS */
511
512#endif /* OS_H */
513