utf8: don't allow NUL in decoded strings.
[ccan] / ccan / sparse_bsearch / sparse_bsearch.c
1 /* Licensed under LGPLv2+ - see LICENSE file for details */
2 #include <sys/types.h> //for ssize_t definition
3 #include "sparse_bsearch.h"
4
5 void *_sparse_bsearch(const void *key, const void *base,
6                       size_t nmemb, size_t size,
7                       int (*cmpfn)(const void *, const void *),
8                       bool (*validfn)(const void *))
9 {
10         ssize_t start = 0, end = nmemb - 1;
11         const char *p = base;
12
13         while (start <= end) {
14                 ssize_t next = (start + end) / 2;
15                 int result;
16
17                 while (!validfn(p + next * size)) {
18                         /* Try the next one along. */
19                         next++;
20                         if (next > end) {
21                                 /* Hmm, none of these were valid. */
22                                 next = (start + end) / 2;
23                                 goto trim;
24                         }
25                 }
26
27                 result = cmpfn(key, p + next * size);
28                 if (result == 0)
29                         return (void *)(p + next * size);
30                 else if (result > 0)
31                         start = next + 1;
32                 else {
33                 trim:
34                         end = next - 1;
35                 }
36         }
37         return NULL;
38 }