tdb2: more tests, hash collision fixes, attribute support.

[ccan] / ccan / hash / test / run.c

diff --git a/ccan/hash/test/run.c b/ccan/hash/test/run.c
index a10e723e0b0cbdaf6f5df60a7242c69fec905c81..31d4ecb59a6ab7c82776f0576994d06b28c79450 100644 (file)
--- a/ccan/hash/test/run.c
+++ b/ccan/hash/test/run.c
@@ -1,6 +1,6 @@
-#include "hash/hash.h"
-#include "tap/tap.h"
-#include "hash/hash.c"
+#include <ccan/hash/hash.h>
+#include <ccan/tap/tap.h>
+#include <ccan/hash/hash.c>
 #include <stdbool.h>
 #include <string.h>
 
@@ -17,43 +17,7 @@ int main(int argc, char *argv[])
        for (i = 0; i < ARRAY_WORDS; i++)
                array[i] = i;
 
-       plan_tests(55);
-
-       /* hash_stable is guaranteed. */
-       ok1(hash_stable(array, ARRAY_WORDS, 0) == 0x13305f8c);
-       ok1(hash_stable(array, ARRAY_WORDS, 1) == 0x171abf74);
-       ok1(hash_stable(array, ARRAY_WORDS, 2) == 0x7646fcc7);
-       ok1(hash_stable(array, ARRAY_WORDS, 4) == 0xa758ed5);
-       ok1(hash_stable(array, ARRAY_WORDS, 8) == 0x2dedc2e4);
-       ok1(hash_stable(array, ARRAY_WORDS, 16) == 0x28e2076b);
-       ok1(hash_stable(array, ARRAY_WORDS, 32) == 0xb73091c5);
-       ok1(hash_stable(array, ARRAY_WORDS, 64) == 0x87daf5db);
-       ok1(hash_stable(array, ARRAY_WORDS, 128) == 0xa16dfe20);
-       ok1(hash_stable(array, ARRAY_WORDS, 256) == 0x300c63c3);
-       ok1(hash_stable(array, ARRAY_WORDS, 512) == 0x255c91fc);
-       ok1(hash_stable(array, ARRAY_WORDS, 1024) == 0x6357b26);
-       ok1(hash_stable(array, ARRAY_WORDS, 2048) == 0x4bc5f339);
-       ok1(hash_stable(array, ARRAY_WORDS, 4096) == 0x1301617c);
-       ok1(hash_stable(array, ARRAY_WORDS, 8192) == 0x506792c9);
-       ok1(hash_stable(array, ARRAY_WORDS, 16384) == 0xcd596705);
-       ok1(hash_stable(array, ARRAY_WORDS, 32768) == 0xa8713cac);
-       ok1(hash_stable(array, ARRAY_WORDS, 65536) == 0x94d9794);
-       ok1(hash_stable(array, ARRAY_WORDS, 131072) == 0xac753e8);
-       ok1(hash_stable(array, ARRAY_WORDS, 262144) == 0xcd8bdd20);
-       ok1(hash_stable(array, ARRAY_WORDS, 524288) == 0xd44faf80);
-       ok1(hash_stable(array, ARRAY_WORDS, 1048576) == 0x2547ccbe);
-       ok1(hash_stable(array, ARRAY_WORDS, 2097152) == 0xbab06dbc);
-       ok1(hash_stable(array, ARRAY_WORDS, 4194304) == 0xaac0e882);
-       ok1(hash_stable(array, ARRAY_WORDS, 8388608) == 0x443f48d0);
-       ok1(hash_stable(array, ARRAY_WORDS, 16777216) == 0xdff49fcc);
-       ok1(hash_stable(array, ARRAY_WORDS, 33554432) == 0x9ce0fd65);
-       ok1(hash_stable(array, ARRAY_WORDS, 67108864) == 0x9ddb1def);
-       ok1(hash_stable(array, ARRAY_WORDS, 134217728) == 0x86096f25);
-       ok1(hash_stable(array, ARRAY_WORDS, 268435456) == 0xe713b7b5);
-       ok1(hash_stable(array, ARRAY_WORDS, 536870912) == 0x5baeffc5);
-       ok1(hash_stable(array, ARRAY_WORDS, 1073741824) == 0xde874f52);
-       ok1(hash_stable(array, ARRAY_WORDS, 2147483648U) == 0xeca13b4e);
-
+       plan_tests(39);
        /* Hash should be the same, indep of memory alignment. */
        val = hash(array, sizeof(array), 0);
        for (i = 0; i < sizeof(uint32_t); i++) {
@@ -87,6 +51,31 @@ int main(int argc, char *argv[])
                diag("Byte %i, range %u-%u", i, lowest, highest);
        }
 
+       /* Hash of random values should have random distribution:
+        * check one byte at a time. */
+       for (i = 0; i < sizeof(uint64_t); i++) {
+               unsigned int lowest = -1U, highest = 0;
+
+               memset(results, 0, sizeof(results));
+
+               for (j = 0; j < 256000; j++) {
+                       for (k = 0; k < ARRAY_WORDS; k++)
+                               array[k] = random();
+                       results[(hash64(array, sizeof(array), 0) >> i*8)&0xFF]++;
+               }
+
+               for (j = 0; j < 256; j++) {
+                       if (results[j] < lowest)
+                               lowest = results[j];
+                       if (results[j] > highest)
+                               highest = results[j];
+               }
+               /* Expect within 20% */
+               ok(lowest > 800, "Byte %i lowest %i", i, lowest);
+               ok(highest < 1200, "Byte %i highest %i", i, highest);
+               diag("Byte %i, range %u-%u", i, lowest, highest);
+       }
+
        /* Hash of pointer values should also have random distribution. */
        for (i = 0; i < sizeof(uint32_t); i++) {
                unsigned int lowest = -1U, highest = 0;
@@ -111,6 +100,13 @@ int main(int argc, char *argv[])
                diag("hash_pointer byte %i, range %u-%u", i, lowest, highest);
        }
 
+       if (sizeof(long) == sizeof(uint32_t))
+               ok1(hashl(array, sizeof(array), 0)
+                   == hash(array, sizeof(array), 0));
+       else
+               ok1(hashl(array, sizeof(array), 0)
+                   == hash64(array, sizeof(array), 0));
+
        /* String hash: weak, so only test bottom byte */
        for (i = 0; i < 1; i++) {
                unsigned int num = 0, cursor, lowest = -1U, highest = 0;