--- a/src/lib/randgen.c	Fri Mar 21 08:27:36 2008 +0200
+++ b/src/lib/randgen.c	Sun Mar 23 17:55:51 2008 +0200
@@ -7,6 +7,8 @@
 
 #ifdef HAVE_DEV_URANDOM
 
+#define URANDOM_PATH "/dev/urandom"
+
 #include "fd-close-on-exec.h"
 #include <unistd.h>
 #include <fcntl.h>
@@ -22,10 +24,16 @@
 	i_assert(init_refcount > 0);
 	i_assert(size < SSIZE_T_MAX);
 
-	for (pos = 0; pos < size; pos += ret) {
+	for (pos = 0; pos < size; ) {
 		ret = read(urandom_fd, (char *) buf + pos, size - pos);
-		if (unlikely(ret < 0 && errno != EINTR))
-			i_fatal("Error reading from /dev/urandom: %m");
+		if (unlikely(ret <= 0)) {
+			if (ret == 0)
+				i_fatal("EOF when reading from "URANDOM_PATH);
+			else if (errno != EINTR)
+				i_fatal("read("URANDOM_PATH") failed: %m");
+		} else {
+			pos += ret;
+		}
 	}
 }
 
@@ -36,13 +44,13 @@
 	if (init_refcount++ > 0)
 		return;
 
-	urandom_fd = open("/dev/urandom", O_RDONLY);
+	urandom_fd = open(URANDOM_PATH, O_RDONLY);
 	if (urandom_fd == -1) {
 		if (errno == ENOENT) {
-			i_fatal("/dev/urandom doesn't exist, "
+			i_fatal(URANDOM_PATH" doesn't exist, "
 				"currently we require it");
 		} else {
-			i_fatal("Can't open /dev/urandom: %m");
+			i_fatal("Can't open "URANDOM_PATH": %m");
 		}
 	}