diff -r 27e940e8e5f3 -r d64aaa7d146f as_rand.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/as_rand.cpp	Fri Nov 28 11:21:08 2008 +0100
@@ -0,0 +1,137 @@
+//
+//  OSSP asgui - Accounting system graphical user interface
+//  Copyright (c) 2002-2004 The OSSP Project (http://www.ossp.org/)
+//  Copyright (c) 2002-2004 Ralf S. Engelschall <rse@engelschall.com>
+//  Copyright (c) 2002-2004 Michael Schloh von Bennewitz <michael@schloh.com>
+//  Copyright (c) 2002-2004 Cable & Wireless Telecommunications Services GmbH
+//
+//  This file is part of OSSP asgui, an accounting system graphical user
+//  interface which can be found at http://www.ossp.org/pkg/tool/asgui/.
+//
+//  Permission to use, copy, modify, and distribute this software for
+//  any purpose with or without fee is hereby granted, provided that
+//  the above copyright notice and this permission notice appear in all
+//  copies.
+//
+//  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+//  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+//  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+//  IN NO EVENT SHALL THE AUTHORS AND COPYRIGHT HOLDERS AND THEIR
+//  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+//  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+//  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+//  USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+//  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+//  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+//  OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+//  SUCH DAMAGE.
+//
+//  as_rand.cpp: ISO C++ implementation
+//
+
+#include <fcntl.h>
+#include <cerrno>
+
+#include "as_rand.h"
+
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif // HAVE_UNISTD_H
+#if HAVE_STDLIB_H
+#include <stdlib.h>
+#endif // HAVE_STDLIB_H
+
+#if TIME_WITH_SYS_TIME
+#include <sys/time.h>
+#include <time.h>
+#else
+#if HAVE_SYS_TIME_H
+#include <sys/time.h>
+#else
+#include <time.h>
+#endif // HAVE_SYS_TIME_H
+#endif // TIME_WITH_SYS_TIME
+
+
+namespace AS {
+
+// Constructor
+Rand::Rand(void)
+{
+    this->nFd = -4; // Object fresh status
+    this->openDevice();   // Open the random device
+//    if (this->nFd < 0)
+//        throw Genexcept("Could not open /dev/urandom or /dev/random.");
+}
+
+// Destructor
+Rand::~Rand(void)
+{
+    this->closeDevice();  // Close the random device
+    this->nFd = -4; // Return this object to its fresh status
+}
+
+//
+// Rand::openDevice(void)
+// Open the random device associated with this object
+//
+void Rand::openDevice(void)
+{
+    struct timeval Time;
+
+    if (this->nFd == -4) {  // -4 indicates a fresh object
+        gettimeofday(&Time, 0);
+        this->nFd = open("/dev/urandom", O_RDONLY);
+        if (this->nFd == -1)
+            this->nFd = open("/dev/random", O_RDONLY | O_NONBLOCK);
+        srand((getpid() << 16) ^ getuid() ^ Time.tv_sec ^ Time.tv_usec); // Seed
+    }
+
+    // Improve randomness by stirring in entropy
+    gettimeofday(&Time, 0);
+    for (int nIter = (Time.tv_sec ^ Time.tv_usec) & 0x1F; nIter > 0; nIter--)
+        rand();
+}
+
+//
+// Rand::closeDevice(void)
+// Close the random device associated with this object
+//
+void Rand::closeDevice(void)
+{
+    if (this->nFd >= 0)
+        close(this->nFd);
+}
+
+//
+// Rand::genData(void *pvBuf, int nBytes)
+// Generate a series of random data from the system
+// standard random devices /dev/[u|s]random
+//
+void Rand::genData(void *pBuf, int nBytes)
+{
+    int nRead = 0;
+    int nLost = 0;
+    char *szOut = (char *)pBuf;
+
+    if (this->nFd >= 0) {
+        while (nBytes > 0) {
+            nRead = read(this->nFd, szOut, nBytes);
+            if ((nRead < 0) && ((errno == EINTR) || (errno == EAGAIN)))
+                continue;
+            if (nRead <= 0) {
+                if (nLost++ == 8)
+                    break;
+                continue;
+            }
+            nBytes -= nRead;
+            szOut += nRead;
+            nLost = 0;
+        }
+    }
+
+    // For systems with no /dev/random, we do the next best thing
+    for (int nIter = 0;  nIter< nBytes; nIter++)
+        *szOut++ = rand() & 0xFF;
+}
+} // namespace AS