From 754c677b0bbf3ea6c7d2a73c93848f1b0d68c91e Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Mon, 20 Jun 2011 16:54:15 +0930 Subject: lib: import ccan modules for tdb2 Imported from git://git.ozlabs.org/~ccan/ccan init-1161-g661d41f Signed-off-by: Rusty Russell --- lib/ccan/asearch/asearch.h | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 lib/ccan/asearch/asearch.h (limited to 'lib/ccan/asearch/asearch.h') diff --git a/lib/ccan/asearch/asearch.h b/lib/ccan/asearch/asearch.h new file mode 100644 index 0000000000..d252284e7d --- /dev/null +++ b/lib/ccan/asearch/asearch.h @@ -0,0 +1,37 @@ +#ifndef CCAN_ASEARCH_H +#define CCAN_ASEARCH_H +#include +#include + +/** + * asearch - search an array of elements + * @key: pointer to item being searched for + * @base: pointer to data to sort + * @num: number of elements + * @cmp: pointer to comparison function + * + * This function does a binary search on the given array. The + * contents of the array should already be in ascending sorted order + * under the provided comparison function. + * + * Note that the key need not have the same type as the elements in + * the array, e.g. key could be a string and the comparison function + * could compare the string with the struct's name field. However, if + * the key and elements in the array are of the same type, you can use + * the same comparison function for both sort() and asearch(). + */ +#if HAVE_TYPEOF +#define asearch(key, base, num, cmp) \ + ((__typeof__(*(base))*)(bsearch((key), (base), (num), sizeof(*(base)), \ + typesafe_cb_cast(int (*)(const void *, const void *), \ + int (*)(const __typeof__(*(key)) *, \ + const __typeof__(*(base)) *), \ + (cmp))))) + +#else +#define asearch(key, base, num, cmp) \ + (bsearch((key), (base), (num), sizeof(*(base)), \ + (int (*)(const void *, const void *))(cmp))) +#endif + +#endif /* CCAN_ASEARCH_H */ -- cgit