Add missing file

1 files changed, 73 insertions, 0 deletions

diff --git a/builtins/siphash.c b/builtins/siphash.c
new file mode 100644
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--- /dev/null
+++ b/builtins/siphash.c
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+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+#include "tomo.h"
+
+/* <MIT License>
+ Copyright (c) 2013  Marek Majkowski <marek@popcount.org>
+ Copyright (c) 2018  Samantha McVey <samantham@posteo.net>
+ Copyright (c) 2024  Bruce Hill <bruce@bruce-hill.com>
+
+ Permission is hereby granted, free of charge, to any person obtaining a copy
+ of this software and associated documentation files (the "Software"), to deal
+ in the Software without restriction, including without limitation the rights
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ copies of the Software, and to permit persons to whom the Software is
+ furnished to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice shall be included in
+ all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ THE SOFTWARE.
+ </MIT License>
+
+ Original location:
+        https://github.com/majek/csiphash/
+
+ Original solution inspired by code from:
+        Samuel Neves (supercop/crypto_auth/siphash24/little)
+        djb (supercop/crypto_auth/siphash24/little2)
+        Jean-Philippe Aumasson (https://131002.net/siphash/siphash24.c)
+
+ Extensive modifications for MoarVM by Samantha McVey
+
+ Further modifications for Tomo by Bruce Hill
+*/
+
+#include "siphash-internals.h"
+
+public uint64_t siphash24(const uint8_t *src, size_t src_sz) {
+    siphash sh;
+    if ((uint64_t)src % __alignof__(uint64_t) == 0) {
+        const uint64_t *in = (uint64_t*)src;
+        /* Find largest src_sz evenly divisible by 8 bytes. */
+        const ptrdiff_t src_sz_nearest_8bits = (src_sz >> 3) << 3;
+        const uint64_t *goal  = (uint64_t*)(src + src_sz_nearest_8bits);
+        siphashinit(&sh, src_sz);
+        src_sz -= src_sz_nearest_8bits;
+        while (in < goal) {
+            siphashadd64bits(&sh, *in);
+            in++;
+        }
+        return siphashfinish(&sh, (uint8_t *)in, src_sz);
+    } else {
+        const uint8_t *in = src;
+        siphashinit(&sh, src_sz);
+        while (src_sz >= 8) {
+            uint64_t in_64;
+            memcpy(&in_64, in, sizeof(uint64_t));
+            siphashadd64bits(&sh, in_64);
+            in += 8; src_sz -= 8;
+        }
+        return siphashfinish(&sh, (uint8_t *)in, src_sz);
+    }
+}
+
+// vim: ts=4 sw=0 et cino=L2,l1,(0,W4,m1,\:0