113 lines
3.2 KiB
C
113 lines
3.2 KiB
C
#ifndef LIBNAGIOS_NSUTILS_H_INCLUDED
|
|
#define LIBNAGIOS_NSUTILS_H_INCLUDED
|
|
#include <sys/types.h>
|
|
#include <sys/time.h>
|
|
|
|
/**
|
|
* @file nsutils.h
|
|
* @brief Non-Standard (or Nagios) utility functions and macros.
|
|
*
|
|
* This is where we house all helpers and macros that fall outside
|
|
* the "standard-ish" norm. The prefixes "nsu_" and NSU_ are
|
|
* reserved for this purpose, so we avoid clashing with other
|
|
* applications that may have similarly-acting functions with
|
|
* identical names.
|
|
*
|
|
* The functions already here lack the nsu_ prefix for backwards
|
|
* compatibility reasons. It's possible we'll have to fix that
|
|
* some day, but let's leave that for later.
|
|
*
|
|
* @{
|
|
*/
|
|
|
|
/** Macro for dynamically increasing vector lengths */
|
|
#define alloc_nr(x) (((x)+16)*3/2)
|
|
|
|
/**
|
|
* Check if a number is a power of 2
|
|
* @param x The number to check
|
|
* @return 1 if the number is a power of 2, 0 if it's not
|
|
*/
|
|
static inline int nsu_ispow2(unsigned int x)
|
|
{
|
|
return x > 1 ? !(x & (x - 1)) : 0;
|
|
}
|
|
|
|
/**
|
|
* Round up to a power of 2
|
|
* Yes, this is the most cryptic function name in all of Nagios, but I
|
|
* like it, so shush.
|
|
* @param r The number to round up
|
|
* @return r, rounded up to the nearest power of 2.
|
|
*/
|
|
static inline unsigned int rup2pof2(unsigned int r)
|
|
{
|
|
r--;
|
|
if (!r)
|
|
return 2;
|
|
r |= r >> 1;
|
|
r |= r >> 2;
|
|
r |= r >> 4;
|
|
r |= r >> 8;
|
|
r |= r >> 16;
|
|
|
|
return r + 1;
|
|
}
|
|
|
|
/**
|
|
* Grab a random unsigned int in the range between low and high.
|
|
* Note that the PRNG has to be seeded prior to calling this.
|
|
* @param low The lower bound, inclusive
|
|
* @param high The higher bound, inclusive
|
|
* @return An unsigned integer in the mathematical range [low, high]
|
|
*/
|
|
static inline unsigned int ranged_urand(unsigned int low, unsigned int high)
|
|
{
|
|
return low + (rand() * (1.0 / (RAND_MAX + 1.0)) * (high - low));
|
|
}
|
|
|
|
/**
|
|
* Get number of online cpus
|
|
* @return Active cpu cores detected on success. 0 on failure.
|
|
*/
|
|
extern int real_online_cpus(void);
|
|
|
|
/**
|
|
* Wrapper for real_online_cpus(), returning 1 in case we can't
|
|
* detect any active cpus.
|
|
* @return Number of active cpu cores on success. 1 on failure.
|
|
*/
|
|
extern int online_cpus(void);
|
|
|
|
/**
|
|
* Create a short-lived string in stack-allocated memory
|
|
* The number and size of strings is limited (currently to 256 strings of
|
|
* 32 bytes each), so beware and use this sensibly. Intended for
|
|
* number-to-string conversion and other short strings.
|
|
* @note The returned string must *not* be free()'d!
|
|
* @param[in] fmt The format string
|
|
* @return A pointer to the formatted string on success. Undefined on errors
|
|
*/
|
|
extern const char *mkstr(const char *fmt, ...)
|
|
__attribute__((__format__(__printf__, 1, 2)));
|
|
|
|
/**
|
|
* Calculate the millisecond delta between two timeval structs
|
|
* @param[in] start The start time
|
|
* @param[in] stop The stop time
|
|
* @return The millisecond delta between the two structs
|
|
*/
|
|
extern int tv_delta_msec(const struct timeval *start, const struct timeval *stop);
|
|
|
|
|
|
/**
|
|
* Get timeval delta as seconds
|
|
* @param start The start time
|
|
* @param stop The stop time
|
|
* @return time difference in fractions of seconds
|
|
*/
|
|
extern float tv_delta_f(const struct timeval *start, const struct timeval *stop);
|
|
|
|
/** @} */
|
|
#endif /* LIBNAGIOS_NSUTILS_H_INCLUDED */
|