walkero
/
harfbuzz
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

[algs] Streamline bsearch some more

This commit is contained in:
Behdad Esfahbod 2019-12-06 03:42:21 +00:00
parent bd55d4b49f
commit 2274270c6a
1 changed files with 32 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

46
src/hb-algs.hh
View File

@ -637,6 +637,36 @@ hb_in_ranges (T u, T lo1, T hi1, T lo2, T hi2, T lo3, T hi3)
* Sort and search.
*/
template <typename V, typename K, typename ...Ts>
static inline bool
hb_bsearch_impl (V** out,
const K& key, V* base,
size_t nmemb, size_t stride,
int (*compar)(const void *_key, const void *_item, Ts... _ds),
Ts... ds)
{
/* This is our *only* bsearch implementation. */
int min = 0, max = (int) nmemb - 1;
while (min <= max)
{
int mid = ((unsigned int) min + (unsigned int) max) / 2;
V* p = (V*) (((const char *) base) + (mid * stride));
int c = compar ((const void *) &key, (const void *) p, ds...);
if (c < 0)
max = mid - 1;
else if (c > 0)
min = mid + 1;
else
{
*out = p;
return true;
}
}
*out = nullptr;
return false;
}
template <typename K, typename V, typename ...Ts>
static int
_cmp_method (const void *pkey, const void *pval, Ts... ds)
@ -654,20 +684,8 @@ hb_bsearch (const K& key, V* base,
int (*compar)(const void *_key, const void *_item, Ts... _ds) = _cmp_method<K, V, Ts...>,
Ts... ds)
{
int min = 0, max = (int) nmemb - 1;
while (min <= max)
{
int mid = ((unsigned int) min + (unsigned int) max) / 2;
V* p = (V*) (((const char *) base) + (mid * stride));
int c = compar ((const void *) &key, (const void *) p, ds...);
if (c < 0)
max = mid - 1;
else if (c > 0)
min = mid + 1;
else
return p;
}
return nullptr;
V* p;
return hb_bsearch_impl (&p, key, base, nmemb, stride, compar, ds...) ? p : nullptr;
}