[PATCH] vt: Use bsearch library function in is_double_width

[Thomas Meyer]

Use bsearch library function instead of duplicated functionality.

Signed-off-by: Thomas Meyer <tho...@m3y3r.de>
---
 drivers/tty/vt/vt.c | 29 ++++++++++++++---------------
 1 file changed, 14 insertions(+), 15 deletions(-)

diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index 2ebaba16f785..ca55004a639e 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -102,6 +102,7 @@
 #include <linux/uaccess.h>
 #include <linux/kdb.h>
 #include <linux/ctype.h>
+#include <linux/bsearch.h>
 
 #define MAX_NR_CON_DRIVER 16
 
@@ -2142,22 +2143,15 @@ struct interval {
        uint32_t last;
 };
 
-static int bisearch(uint32_t ucs, const struct interval *table, int max)
+static int ucs_cmp(const void *key, const void *elt)
 {
-       int min = 0;
-       int mid;
+       uint32_t ucs = *(uint32_t *)key;
+       struct interval e = *(struct interval *) elt;
 
-       if (ucs < table[0].first || ucs > table[max].last)
-               return 0;
-       while (max >= min) {
-               mid = (min + max) / 2;
-               if (ucs > table[mid].last)
-                       min = mid + 1;
-               else if (ucs < table[mid].first)
-                       max = mid - 1;
-               else
-                       return 1;
-       }
+       if (ucs > e.last)
+               return 1;
+       else if (ucs < e.first)
+               return -1;
        return 0;
 }
 
@@ -2169,7 +2163,12 @@ static int is_double_width(uint32_t ucs)
                { 0xFE10, 0xFE19 }, { 0xFE30, 0xFE6F }, { 0xFF00, 0xFF60 },
                { 0xFFE0, 0xFFE6 }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD }
        };
-       return bisearch(ucs, double_width, ARRAY_SIZE(double_width) - 1);
+       if (ucs < double_width[0].first ||
+           ucs > double_width[ARRAY_SIZE(double_width) - 1].last)
+               return 0;
+
+       return bsearch(&ucs, double_width, ARRAY_SIZE(double_width),
+                       sizeof(struct interval), ucs_cmp) != NULL;
 }
 
 static void con_flush(struct vc_data *vc, unsigned long draw_from,
-- 
2.11.0