Libc-1272.200.26.tar.gz

[apple/libc.git] / libdarwin / stdlib.c

diff --git a/libdarwin/stdlib.c b/libdarwin/stdlib.c
new file mode 100644 (file)
index 0000000..d718a94
--- /dev/null
+++ b/libdarwin/stdlib.c
@@ -0,0 +1,133 @@
+/*
+ * Copyright (c) 2018 Apple Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
+#include "internal.h"
+
+#pragma mark API
+void
+os_localtime_file(char buff[32])
+{
+       struct timeval tv;
+       struct tm curtime;
+
+       posix_assert_zero(gettimeofday(&tv, NULL));
+       (void)localtime_r(&tv.tv_sec, &curtime);
+
+       // Return a time representation that is ideal for use in filenames, so no
+       // spaces or things that need to be escaped.
+       snprintf(buff, 32, "%d-%02d-%02d_%02d.%02d.%02d.%06d",
+                       curtime.tm_year + 1900, curtime.tm_mon + 1, curtime.tm_mday,
+                       curtime.tm_hour, curtime.tm_min, curtime.tm_sec, tv.tv_usec);
+}
+
+// MurmurHash2 was written by Austin Appleby, and is placed in the public
+// domain. The author hereby disclaims copyright to this source code.
+uint64_t
+os_simple_hash(const void *buff, size_t len)
+{
+       const uint64_t seed = 0;
+#ifdef __LP64__
+       // MurmurHash64A
+       const uint64_t m = 0xc6a4a7935bd1e995;
+       const int r = 47;
+       uint64_t h = seed ^ (len * m);
+       const uint64_t * data = (const uint64_t *)buff;
+       const uint64_t * end = data + (len / 8);
+       while(data != end) {
+               uint64_t k = *data++;
+               k *= m;
+               k ^= k >> r;
+               k *= m;
+               h ^= k;
+               h *= m;
+       }
+       const unsigned char * data2 = (const unsigned char *)data;
+       switch(len & 7) {
+       case 7: h ^= ((uint64_t)data2[6]) << 48;
+       case 6: h ^= ((uint64_t)data2[5]) << 40;
+       case 5: h ^= ((uint64_t)data2[4]) << 32;
+       case 4: h ^= ((uint64_t)data2[3]) << 24;
+       case 3: h ^= ((uint64_t)data2[2]) << 16;
+       case 2: h ^= ((uint64_t)data2[1]) << 8;
+       case 1: h ^= ((uint64_t)data2[0]);
+                       h *= m;
+       };
+       h ^= h >> r;
+       h *= m;
+       h ^= h >> r;
+#else // __LP64__
+       // MurmurHash64B
+       const uint32_t m = 0x5bd1e995;
+       const int r = 24;
+
+       uint32_t h1 = (uint32_t)(seed) ^ len;
+       uint32_t h2 = (uint32_t)(seed >> 32);
+
+       const uint32_t * data = (const uint32_t *)buff;
+
+#define MIX(k, h) \
+       (k) *= m; (k) ^= (k) >> r; (k) *= m; (h) *= m; (h) ^= (k); len -= 4;
+
+       while(len >= 8) {
+               uint32_t k[2];
+               memcpy(k, (const char*)data, sizeof(k));
+               data += sizeof(k)/sizeof(k[0]);
+
+               MIX(k[0], h1)
+               MIX(k[1], h2)
+       }
+
+       if(len >= 4) {
+               uint32_t k[1];
+               memcpy(k, (const char *)data, sizeof(k));
+               data += sizeof(k)/sizeof(k[0]);
+
+               MIX(k[0], h1);
+       }
+
+#undef MIX
+
+       switch(len) {
+       case 3: h2 ^= ((unsigned char*)data)[2] << 16;
+       case 2: h2 ^= ((unsigned char*)data)[1] << 8;
+       case 1: h2 ^= ((unsigned char*)data)[0];
+                       h2 *= m;
+       };
+
+       h1 ^= h2 >> 18; h1 *= m;
+       h2 ^= h1 >> 22; h2 *= m;
+       h1 ^= h2 >> 17; h1 *= m;
+       h2 ^= h1 >> 19; h2 *= m;
+
+       uint64_t h = h1;
+
+       h = (h << 32) | h2;
+#endif // __LP64__
+       return h;
+}
+
+uint64_t
+os_simple_hash_string(const char *string)
+{
+       size_t len = strlen(string);
+       return os_simple_hash(string, len);
+}