Add bsearchr

1 files changed, 17 insertions, 0 deletions

diff --git a/src/libposixplz/bsearchr.c b/src/libposixplz/bsearchr.c
new file mode 100644
index 0000000..87b664f
--- /dev/null
+++ b/src/libposixplz/bsearchr.c
@@ -0,0 +1,17 @@
+/* ISC license. */
+
+#include <skalibs/functypes.h>
+#include <skalibs/posixplz.h>
+
+void *bsearchr (void const *key, void const *base, size_t n, size_t width, cmp_func_ref cmp, void *aux)
+{
+  while (n)
+  {
+    void *cur = (char *)base + width * (n >> 1) ;
+    int h = (*cmp)(key, cur, aux) ;
+    if (h < 0) n >>= 1 ;
+    else if (h > 0) { base = (char *)cur + width ; n = (n-1) >> 1 ; }
+    else return cur ;
+  }
+  return 0 ;
+}