Move VFS sources into Kernel/.

Kernel/RandomDevice.cpp

@@ -0,0 +1,53 @@
+#include "RandomDevice.h"
+#include "Limits.h"
+#include <AK/StdLibExtras.h>
+
+RandomDevice::RandomDevice()
+    : CharacterDevice(1, 8)
+{
+}
+
+RandomDevice::~RandomDevice()
+{
+}
+
+// Simple rand() and srand() borrowed from the POSIX standard:
+
+static unsigned long next = 1;
+
+#define MY_RAND_MAX 32767
+static int myrand()
+{
+    next = next * 1103515245 + 12345;
+    return((unsigned)(next/((MY_RAND_MAX + 1) * 2)) % (MY_RAND_MAX + 1));
+}
+
+#if 0
+static void mysrand(unsigned seed)
+{
+    next = seed;
+}
+#endif
+
+bool RandomDevice::can_read(Process&) const
+{
+    return true;
+}
+
+ssize_t RandomDevice::read(Process&, byte* buffer, size_t bufferSize)
+{
+    const int range = 'z' - 'a';
+    ssize_t nread = min(bufferSize, GoodBufferSize);
+    for (ssize_t i = 0; i < nread; ++i) {
+        dword r = myrand() % range;
+        buffer[i] = 'a' + r;
+    }
+    return nread;
+}
+
+ssize_t RandomDevice::write(Process&, const byte*, size_t bufferSize)
+{
+    // FIXME: Use input for entropy? I guess that could be a neat feature?
+    return min(GoodBufferSize, bufferSize);
+}
+