/*
* get_icount_el() --- given an inode number, try to find icount
* information in the sorted list. If the create flag is set,
* and we can't find an entry, create one in the sorted list.
*/
static struct ext2_icount_el *get_icount_el(ext2_icount_t icount,
ext2_ino_t ino, int create)
{
float range;
int low, high, mid;
ext2_ino_t lowval, highval;
if (!icount || !icount->list)
return 0;
if (create && ((icount->count == 0) ||
(ino > icount->list[(unsigned)icount->count-1].ino))) {
return insert_icount_el(icount, ino, (unsigned) icount->count);
}
if (icount->count == 0)
return 0;
if (icount->cursor >= icount->count)
icount->cursor = 0;
if (ino == icount->list[icount->cursor].ino)
return &icount->list[icount->cursor++];
#if 0
printf("Non-cursor get_icount_el: %u\n", ino);
#endif
low = 0;
high = (int) icount->count-1;
while (low <= high) {
mid = ((unsigned)low + (unsigned)high) >> 1;
if (ino == icount->list[mid].ino) {
icount->cursor = mid+1;
return &icount->list[mid];
}
if (ino < icount->list[mid].ino)
high = mid-1;
else
low = mid+1;
}
/*
* If we need to create a new entry, it should be right at
* low (where high will be left at low-1).
*/
if (create)
return insert_icount_el(icount, ino, low);
return 0;
}
/*
* get_icount_el() --- given an inode number, try to find icount
* information in the sorted list. If the create flag is set,
* and we can't find an entry, create one in the sorted list.
*/
static struct ext2_icount_el *get_icount_el(ext2_icount_t icount,
ext2_ino_t ino, int create)
{
float range;
int low, high, mid;
ext2_ino_t lowval, highval;
if (!icount || !icount->list)
return 0;
if (create && ((icount->count == 0) ||
(ino > icount->list[(unsigned)icount->count-1].ino))) {
return insert_icount_el(icount, ino, (unsigned) icount->count);
}
if (icount->count == 0)
return 0;
if (icount->cursor >= icount->count)
icount->cursor = 0;
if (ino == icount->list[icount->cursor].ino)
return &icount->list[icount->cursor++];
#if 0
printf("Non-cursor get_icount_el: %u\n", ino);
#endif
low = 0;
high = (int) icount->count-1;
while (low <= high) {
#if 0
mid = (low+high)/2;
#else
if (low == high)
mid = low;
else {
/* Interpolate for efficiency */
lowval = icount->list[low].ino;
highval = icount->list[high].ino;
if (ino < lowval)
range = 0;
else if (ino > highval)
range = 1;
else {
range = ((float) (ino - lowval)) /
(highval - lowval);
if (range > 0.9)
range = 0.9;
if (range < 0.1)
range = 0.1;
}
mid = low + ((int) (range * (high-low)));
}
#endif
if (ino == icount->list[mid].ino) {
icount->cursor = mid+1;
return &icount->list[mid];
}
if (ino < icount->list[mid].ino)
high = mid-1;
else
low = mid+1;
}
/*
* If we need to create a new entry, it should be right at
* low (where high will be left at low-1).
*/
if (create)
return insert_icount_el(icount, ino, low);
return 0;
}
