C++ (or C99) sneak attack ("inline" function keyword).

[p5sagit/p5-mst-13.2.git] / util.c

diff --git a/util.c b/util.c
index 80af155..9a43d67 100644 (file)
--- a/util.c
+++ b/util.c
@@ -4377,3 +4377,35 @@ Perl_seed(pTHX)
     return u;
 }
 
+UV
+Perl_get_hash_seed(pTHX)
+{
+     char *s = PerlEnv_getenv("PERL_HASH_SEED");
+     UV myseed = 0;
+
+     if (s)
+         while (isSPACE(*s)) s++;
+     if (s && isDIGIT(*s))
+         myseed = (UV)Atoul(s);
+     else
+#ifdef USE_HASH_SEED_EXPLICIT
+     if (s)
+#endif
+     {
+         /* Compute a random seed */
+         (void)seedDrand01((Rand_seed_t)seed());
+         PL_srand_called = TRUE;
+         myseed = (UV)(Drand01() * (NV)UV_MAX);
+#if RANDBITS < (UVSIZE * 8)
+         /* Since there are not enough randbits to to reach all
+          * the bits of a UV, the low bits might need extra
+          * help.  Sum in another random number that will
+          * fill in the low bits. */
+         myseed +=
+              (UV)(Drand01() * (NV)((1 << ((UVSIZE * 8 - RANDBITS))) - 1));
+#endif /* RANDBITS < (UVSIZE * 8) */
+     }
+     PL_hash_seed_set = TRUE;
+
+     return myseed;
+}