MFC r309650:

  Properly sign extend the result of jrand48() and mrand48().

  These functions are supposed to return a value between [-2^31, 2^31).
  This doesn't seem to work on 64-bit systems, where we return a value
  between [0, 3^32). Patch up the function to use proper casts to int32_t.
  While there, fix some other style bugs.

2 files changed, 9 insertions, 2 deletions

diff --git a/lib/libc/gen/jrand48.c b/lib/libc/gen/jrand48.c
index 1707620..5aab1e1 100644
--- a/lib/libc/gen/jrand48.c
+++ b/lib/libc/gen/jrand48.c
@@ -14,11 +14,14 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include <stdint.h>
+
 #include "rand48.h"
 
 long
 jrand48(unsigned short xseed[3])
 {
+
 	_dorand48(xseed);
-	return ((long) xseed[2] << 16) + (long) xseed[1];
+	return ((int32_t)(((uint32_t)xseed[2] << 16) | (uint32_t)xseed[1]));
 }
diff --git a/lib/libc/gen/mrand48.c b/lib/libc/gen/mrand48.c
index ef20fb87b..795a858 100644
--- a/lib/libc/gen/mrand48.c
+++ b/lib/libc/gen/mrand48.c
@@ -14,6 +14,8 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include <stdint.h>
+
 #include "rand48.h"
 
 extern unsigned short _rand48_seed[3];
@@ -21,6 +23,8 @@ extern unsigned short _rand48_seed[3];
 long
 mrand48(void)
 {
+
 	_dorand48(_rand48_seed);
-	return ((long) _rand48_seed[2] << 16) + (long) _rand48_seed[1];
+	return ((int32_t)(((uint32_t)_rand48_seed[2] << 16) |
+	    (uint32_t)_rand48_seed[1]));
 }