add skeleton of symbols from C11 LIB_EXT1

1 files changed, 49 insertions, 0 deletions

diff --git a/src/stdlib/bsearch_s.c b/src/stdlib/bsearch_s.c
new file mode 100644
index 00000000..12a19c25
--- /dev/null
+++ b/src/stdlib/bsearch_s.c
@@ -0,0 +1,49 @@
+#include <stddef.h>
+
+/** binary search **/
+void *bsearch_s(const void * key, const void * base,
+	rsize_t nmemb, rsize_t size,
+	int (*compar)(const void *x, const void *y, void * context),
+	void *context)
+{
+	__C_EXT(1, 201112L);
+	/* TODO: testing */
+	void *ret = NULL;
+	size_t i = nmemb / 2;
+	unsigned int trip = 1;
+
+	while (ret == NULL) {
+		int comp = compar(key, base+i);
+		if (comp == 0) {
+			return (void*)base+i;
+		} else if (comp > 0) {
+			i -= (nmemb >> trip);
+		} else {
+			i += (nmemb >> trip);
+		}
+	}
+	return NULL;
+}
+
+/***
+The fn(bsearch) function performs a binary search for arg(key) in the array
+arg(base), which contains arg(nmemb) members of arg(size) bytes each.
+
+The search is performed by calling arg(compar) with the first argument of
+arg(key), and the second being an element from the array at arg(base). The
+function must return less than 0 if arg(key) is less than the other element,
+0 if they are equal, and greater than 0 if arg(key) is greater than the other
+element.
+***/
+
+/* UNSPECIFIED: which element is matched if two elements are equal */
+/* UNDEFINED: the array at arg(base) is not sorted */
+/* IMPLEMENTATION: - */
+/* LOCALE: - */
+
+/* RETURN(NULL): no match was found */
+/* RETURN: a pointer to the matching element */
+
+/*
+CEXT1(201112)
+*/