Merge remote-tracking branch 'warcraft_hash/master'

wc3hash.c

@@ -0,0 +1,81 @@
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include <inttypes.h>
+
+typedef uint8_t u8;
+typedef uint32_t u32;
+typedef uint64_t u64;
+
+const u64 table[16] = {
+    // magic numbers for each possible value of a nybble.
+    0x486E26EEDCAA16B3, 0xE1918EEF202DAFDB,
+    0x341C7DC71C365303, 0x40EF2D3765FD5E49,
+    0xD6057177904ECE93, 0x1C38024F98FD323B,
+    0xE3061AE7A39B0FA1, 0x9797F25FE4444563,
+    0xCD2EC20C8DC1B898, 0x31759633799A306D,
+    0x8C2063852E6E9627, 0x79237D9973922C66,
+    0x8728628D28628824, 0x8F1F7E9625887795,
+    0x296E3281389C0D60, 0x6F4893CA61636542
+};
+
+u64 wc3hash(const char *key, size_t len, u64 hash, bool isPath) {
+    // technically there doesn't seem to be a
+    // length argument in the original function,
+    // I'm just adding it so you can hash strings with '\0' in them.
+
+    if (key == NULL)
+        return 0;
+
+    if (hash == 0)
+        hash = 0x7FED7FED7FED7FED;
+
+    u64 state = 0xEEEEEEEEEEEEEEEE;
+
+    for (size_t i = 0; i < len; i++) {
+        u8 v;
+        if (isPath) {
+            char c = key[i];
+            if (c >= 'a' && c <= 'z')
+                c -= 'a' - 'A'; // uppercase
+            if (c == '/')
+                c = '\\'; // DOS-style paths
+
+            v = (u8)c;
+        } else {
+            v = (u8)key[i];
+        }
+
+        hash += state;
+        hash ^= table[v >> 4] + table[v & 0xF];
+        state += state << 5;
+        state += hash + v + 3;
+    }
+
+    if (hash == 0)
+        return 1;
+
+    return hash;
+}
+
+u64 wc3hashC(const char *key) {
+    // simple interface that only takes a null-terminated string.
+    return wc3hash(key, strlen(key), 0, true);
+}
+
+int main(int argc, char **argv) {
+    if (argc == 1) {
+        const char str[] = "IseeDeadPeople";
+        u64 hash = wc3hashC(str);
+        fprintf(stderr, "%" PRIX64 " should equal 701EA16D47F385FC\n", hash);
+        return hash != 0x701EA16D47F385FC;
+    }
+
+    for (int i = 1; i < argc; i++) {
+        u64 hash = wc3hashC(argv[i]);
+        u32 hash32 = (hash >> 32) ^ hash;
+        printf("%" PRIX64 "\t%08X\n", hash, hash32);
+    }
+    return 0;
+}