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-rw-r--r--src/stdlib/bsearch.c20
1 files changed, 20 insertions, 0 deletions
diff --git a/src/stdlib/bsearch.c b/src/stdlib/bsearch.c
new file mode 100644
index 00000000..61d89367
--- /dev/null
+++ b/src/stdlib/bsearch.c
@@ -0,0 +1,20 @@
+#include <stdlib.h>
+
+void *bsearch(const void *key, const void *base, size_t nel, size_t width, int (*cmp)(const void *, const void *))
+{
+	void *try;
+	int sign;
+	while (nel > 0) {
+		try = (char *)base + width*(nel/2);
+		sign = cmp(key, try);
+		if (!sign) return try;
+		else if (nel == 1) break;
+		else if (sign < 0)
+			nel /= 2;
+		else {
+			base = try;
+			nel -= nel/2;
+		}
+	}
+	return NULL;
+}