blob: 69d86258d21cc27d87224c472ace54c0588d24af [file] [log] [blame]
extern void abort (void);
typedef struct foo_t
{
unsigned int blksz;
unsigned int bf_cnt;
} foo_t;
#define _RNDUP(x, unit) ((((x) + (unit) - 1) / (unit)) * (unit))
#define _RNDDOWN(x, unit) ((x) - ((x)%(unit)))
long long
foo (foo_t *const pxp, long long offset, unsigned int extent)
{
long long blkoffset = _RNDDOWN(offset, (long long )pxp->blksz);
unsigned int diff = (unsigned int)(offset - blkoffset);
unsigned int blkextent = _RNDUP(diff + extent, pxp->blksz);
if (pxp->blksz < blkextent)
return -1LL;
if (pxp->bf_cnt > pxp->blksz)
pxp->bf_cnt = pxp->blksz;
return blkoffset;
}
int
main ()
{
foo_t x;
long long xx;
x.blksz = 8192;
x.bf_cnt = 0;
xx = foo (&x, 0, 4096);
if (xx != 0LL)
abort ();
return 0;
}