- /* Select median value from among LO, MID, and HI. Rearrange
- LO and HI so the three values are sorted. This lowers the
- probability of picking a pathological pivot value and
- skips a comparison for both the LEFT_PTR and RIGHT_PTR. */
-
- char *mid = lo + size * ((hi - lo) / size >> 1);
-
- if ((*cmp) ((void *) mid, (void *) lo, user_data) < 0)
- SWAP (mid, lo, size);
- if ((*cmp) ((void *) hi, (void *) mid, user_data) < 0)
- SWAP (mid, hi, size);
- else
- goto jump_over;
- if ((*cmp) ((void *) mid, (void *) lo, user_data) < 0)
- SWAP (mid, lo, size);
- jump_over:;
- left_ptr = lo + size;
- right_ptr = hi - size;
-
- /* Here's the famous ``collapse the walls'' section of quicksort.
- Gotta like those tight inner loops! They are the main reason
- that this algorithm runs much faster than others. */
- do
- {
- while ((*cmp) ((void *) left_ptr, (void *) mid, user_data) < 0)
- left_ptr += size;
-
- while ((*cmp) ((void *) mid, (void *) right_ptr, user_data) < 0)
- right_ptr -= size;
-
- if (left_ptr < right_ptr)
- {
- SWAP (left_ptr, right_ptr, size);
- if (mid == left_ptr)
- mid = right_ptr;
- else if (mid == right_ptr)
- mid = left_ptr;
- left_ptr += size;
- right_ptr -= size;
- }
- else if (left_ptr == right_ptr)
- {
- left_ptr += size;
- right_ptr -= size;
- break;
- }
- }
- while (left_ptr <= right_ptr);
+ /* Select median value from among LO, MID, and HI. Rearrange
+ LO and HI so the three values are sorted. This lowers the
+ probability of picking a pathological pivot value and
+ skips a comparison for both the LEFT_PTR and RIGHT_PTR. */
+
+ char *mid = lo + size * ((hi - lo) / size >> 1);
+
+ if ((*cmp) ((void *) mid, (void *) lo, user_data) < 0)
+ SWAP (mid, lo, size);
+ if ((*cmp) ((void *) hi, (void *) mid, user_data) < 0)
+ SWAP (mid, hi, size);
+ else
+ goto jump_over;
+ if ((*cmp) ((void *) mid, (void *) lo, user_data) < 0)
+ SWAP (mid, lo, size);
+ jump_over:;
+ left_ptr = lo + size;
+ right_ptr = hi - size;
+
+ /* Here's the famous ``collapse the walls'' section of quicksort.
+ Gotta like those tight inner loops! They are the main reason
+ that this algorithm runs much faster than others. */
+ do
+ {
+ while ((*cmp) ((void *) left_ptr, (void *) mid, user_data) < 0)
+ left_ptr += size;
+
+ while ((*cmp) ((void *) mid, (void *) right_ptr, user_data) < 0)
+ right_ptr -= size;
+
+ if (left_ptr < right_ptr)
+ {
+ SWAP (left_ptr, right_ptr, size);
+ if (mid == left_ptr)
+ mid = right_ptr;
+ else if (mid == right_ptr)
+ mid = left_ptr;
+ left_ptr += size;
+ right_ptr -= size;
+ }
+ else if (left_ptr == right_ptr)
+ {
+ left_ptr += size;
+ right_ptr -= size;
+ break;
+ }
+ }
+ while (left_ptr <= right_ptr);