WT-2858 Rename wtperf's CONFIG structure (#3065)

Also replace key-string generation implementation with a more efficient implementation.

1 files changed, 56 insertions, 0 deletions

diff --git a/test/utility/test_util.h b/test/utility/test_util.h
index 3c1d0e2630a..1047d1ca8a0 100644
--- a/test/utility/test_util.h
+++ b/test/utility/test_util.h
@@ -108,6 +108,62 @@ typedef struct {
 		    __func__, __LINE__, #call, __VA_ARGS__);		\
 } while (0)
 
+/*
+ * u64_to_string --
+ *	Convert a uint64_t to a text string.
+ *
+ * Algorithm from Andrei Alexandrescu's talk: "Three Optimization Tips for C++"
+ */
+static inline void
+u64_to_string(uint64_t n, char **pp)
+{
+	static const char hundred_lookup[201] =
+	    "0001020304050607080910111213141516171819"
+	    "2021222324252627282930313233343536373839"
+	    "4041424344454647484950515253545556575859"
+	    "6061626364656667686970717273747576777879"
+	    "8081828384858687888990919293949596979899";
+	u_int i;
+	char *p;
+
+	/*
+	 * The argument pointer references the last element of a buffer (which
+	 * must be large enough to hold any possible value).
+	 *
+	 * Nul-terminate the buffer.
+	 */
+	for (p = *pp, *p-- = '\0'; n >= 100; n /= 100) {
+		i = (n % 100) * 2;
+		*p-- = hundred_lookup[i + 1];
+		*p-- = hundred_lookup[i];
+	}
+
+	/* Handle the last two digits. */
+	i = (u_int)n * 2;
+	*p = hundred_lookup[i + 1];
+	if (n >= 10)
+		*--p = hundred_lookup[i];
+
+	/* Return a pointer to the first byte of the text string. */
+	*pp = p;
+}
+
+/*
+ * u64_to_string_zf --
+ *	Convert a uint64_t to a text string, zero-filling the buffer.
+ */
+static inline void
+u64_to_string_zf(uint64_t n, char *buf, size_t len)
+{
+	char *p;
+
+	p = buf + (len - 1);
+	u64_to_string(n, &p);
+
+	while (p > buf)
+		*--p = '0';
+}
+
 /* Allow tests to add their own death handling. */
 extern void (*custom_die)(void);