Move hash into ccan/ dir

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

diff --git a/ccan/hash/test/run.c b/ccan/hash/test/run.c
new file mode 100644 (file)
index 0000000..a10e723
--- /dev/null
+++ b/ccan/hash/test/run.c
@@ -0,0 +1,152 @@
+#include "hash/hash.h"
+#include "tap/tap.h"
+#include "hash/hash.c"
+#include <stdbool.h>
+#include <string.h>
+
+#define ARRAY_WORDS 5
+
+int main(int argc, char *argv[])
+{
+       unsigned int i, j, k;
+       uint32_t array[ARRAY_WORDS], val;
+       char array2[sizeof(array) + sizeof(uint32_t)];
+       uint32_t results[256];
+
+       /* Initialize array. */
+       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);
+
+       /* Hash should be the same, indep of memory alignment. */
+       val = hash(array, sizeof(array), 0);
+       for (i = 0; i < sizeof(uint32_t); i++) {
+               memcpy(array2 + i, array, sizeof(array));
+               ok(hash(array2 + i, sizeof(array), 0) != val,
+                  "hash matched at offset %i", i);
+       }
+
+       /* Hash of random values should have random distribution:
+        * check one byte at a time. */
+       for (i = 0; i < sizeof(uint32_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[(hash(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;
+               char *p = malloc(256000);
+
+               memset(results, 0, sizeof(results));
+
+               for (j = 0; j < 256000; j++)
+                       results[(hash_pointer(p + j, 0) >> i*8)&0xFF]++;
+               free(p);
+
+               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, "hash_pointer byte %i lowest %i", i, lowest);
+               ok(highest < 1200, "hash_pointer byte %i highest %i",
+                  i, highest);
+               diag("hash_pointer byte %i, range %u-%u", i, lowest, highest);
+       }
+
+       /* String hash: weak, so only test bottom byte */
+       for (i = 0; i < 1; i++) {
+               unsigned int num = 0, cursor, lowest = -1U, highest = 0;
+               char p[5];
+
+               memset(results, 0, sizeof(results));
+
+               memset(p, 'A', sizeof(p));
+               p[sizeof(p)-1] = '\0';
+
+               for (;;) {
+                       for (cursor = 0; cursor < sizeof(p)-1; cursor++) {
+                               p[cursor]++;
+                               if (p[cursor] <= 'z')
+                                       break;
+                               p[cursor] = 'A';
+                       }
+                       if (cursor == sizeof(p)-1)
+                               break;
+
+                       results[(hash_string(p) >> i*8)&0xFF]++;
+                       num++;
+               }
+
+               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 > 35000, "hash_pointer byte %i lowest %i", i, lowest);
+               ok(highest < 53000, "hash_pointer byte %i highest %i",
+                  i, highest);
+               diag("hash_pointer byte %i, range %u-%u", i, lowest, highest);
+       }
+
+       return exit_status();
+}