MFC r271879:

awk: Use random(3) instead of rand(3)

While none of them is considered even near to cryptographic
level, random(3) is a better random generator than rand(3).

Use random(3) for awk as is done in other systems.

PR:		193147

3 files changed, 7 insertions, 5 deletions

diff --git a/contrib/one-true-awk/awk.1 b/contrib/one-true-awk/awk.1
index 6119613..b0d243b 100644
--- a/contrib/one-true-awk/awk.1
+++ b/contrib/one-true-awk/awk.1
@@ -208,7 +208,7 @@ or of
 if no argument.
 .TP
 .B rand
-random number on (0,1)
+random number on [0,1)
 .TP
 .B srand
 sets seed for
diff --git a/contrib/one-true-awk/main.c b/contrib/one-true-awk/main.c
index ab01676..ec70294 100644
--- a/contrib/one-true-awk/main.c
+++ b/contrib/one-true-awk/main.c
@@ -74,7 +74,7 @@ int main(int argc, char *argv[])
 	signal(SIGFPE, fpecatch);
 
 	srand_seed = 1;
-	srand(srand_seed);
+	srandom((unsigned long) srand_seed);
 
 	yyin = NULL;
 	symtab = makesymtab(NSYMTAB/NSYMTAB);
diff --git a/contrib/one-true-awk/run.c b/contrib/one-true-awk/run.c
index cafaff3..2bcd9df 100644
--- a/contrib/one-true-awk/run.c
+++ b/contrib/one-true-awk/run.c
@@ -1521,8 +1521,10 @@ Cell *bltin(Node **a, int n)	/* builtin functions. a[0] is type, a[1] is arg lis
 		u = (Awkfloat) system(getsval(x)) / 256;   /* 256 is unix-dep */
 		break;
 	case FRAND:
-		/* in principle, rand() returns something in 0..RAND_MAX */
-		u = (Awkfloat) (rand() % RAND_MAX) / RAND_MAX;
+		/* random() returns numbers in [0..2^31-1]
+		 * in order to get a number in [0, 1), divide it by 2^31
+		 */
+		u = (Awkfloat) random() / (0x7fffffffL + 0x1UL);
 		break;
 	case FSRAND:
 		if (isrec(x))	/* no argument provided */
@@ -1530,7 +1532,7 @@ Cell *bltin(Node **a, int n)	/* builtin functions. a[0] is type, a[1] is arg lis
 		else
 			u = getfval(x);
 		tmp = u;
-		srand((unsigned int) u);
+		srandom((unsigned long) u);
 		u = srand_seed;
 		srand_seed = tmp;
 		break;