src/utils/os.h

   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 long 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 */