Adding gem5 source to svn.

git-svn-id: https://www4.informatik.uni-erlangen.de/i4svn/danceos/trunk/devel/fail@1819 8c4709b5-6ec9-48aa-a5cd-a96041d1645a

simulators/gem5/src/base/circlebuf.cc

@@ -0,0 +1,214 @@
+/*
+ * Copyright (c) 2002-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS 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 COPYRIGHT
+ * OWNER OR 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.
+ *
+ * Authors: Nathan Binkert
+ */
+
+#include <algorithm>
+#include <cstdio>
+#include <cstring>
+#include <string>
+
+#include "base/atomicio.hh"
+#include "base/circlebuf.hh"
+#include "base/cprintf.hh"
+#include "base/intmath.hh"
+
+using namespace std;
+
+CircleBuf::CircleBuf(int l)
+    : _rollover(false), _buflen(l), _size(0), _start(0), _stop(0)
+{
+    _buf = new char[_buflen];
+}
+
+CircleBuf::~CircleBuf()
+{
+    if (_buf)
+        delete [] _buf;
+}
+
+void
+CircleBuf::dump()
+{
+    cprintf("start = %10d, stop = %10d, buflen = %10d\n",
+            _start, _stop, _buflen);
+    fflush(stdout);
+    atomic_write(STDOUT_FILENO, _buf, _buflen);
+    atomic_write(STDOUT_FILENO, "<\n", 2);
+}
+
+void
+CircleBuf::flush()
+{
+    _start = 0;
+    _stop = 0;
+    _rollover = false;
+}
+
+void
+CircleBuf::read(char *b, int len)
+{
+    _size -= len;
+    if (_size < 0)
+        _size = 0;
+
+    if (_stop > _start) {
+        len = min(len, _stop - _start);
+        memcpy(b, _buf + _start, len);
+        _start += len;
+    }
+    else {
+        int endlen = _buflen - _start;
+        if (endlen > len) {
+            memcpy(b, _buf + _start, len);
+            _start += len;
+        }
+        else {
+            memcpy(b, _buf + _start, endlen);
+            _start = min(len - endlen, _stop);
+            memcpy(b + endlen, _buf, _start);
+        }
+    }
+}
+
+void
+CircleBuf::read(int fd, int len)
+{
+    _size -= len;
+    if (_size < 0)
+        _size = 0;
+
+    if (_stop > _start) {
+        len = min(len, _stop - _start);
+        atomic_write(fd, _buf + _start, len);
+        _start += len;
+    }
+    else {
+        int endlen = _buflen - _start;
+        if (endlen > len) {
+            atomic_write(fd, _buf + _start, len);
+            _start += len;
+        }
+        else {
+            atomic_write(fd, _buf + _start, endlen);
+            _start = min(len - endlen, _stop);
+            atomic_write(fd, _buf, _start);
+        }
+    }
+}
+
+void
+CircleBuf::read(int fd)
+{
+    _size = 0;
+
+    if (_stop > _start) {
+        atomic_write(fd, _buf + _start, _stop - _start);
+    }
+    else {
+        atomic_write(fd, _buf + _start, _buflen - _start);
+        atomic_write(fd, _buf, _stop);
+    }
+
+    _start = _stop;
+}
+
+void
+CircleBuf::read(ostream &out)
+{
+    _size = 0;
+
+    if (_stop > _start) {
+        out.write(_buf + _start, _stop - _start);
+    }
+    else {
+        out.write(_buf + _start, _buflen - _start);
+        out.write(_buf, _stop);
+    }
+
+    _start = _stop;
+}
+
+void
+CircleBuf::readall(int fd)
+{
+    if (_rollover)
+        atomic_write(fd, _buf + _stop, _buflen - _stop);
+
+    atomic_write(fd, _buf, _stop);
+    _start = _stop;
+}
+
+void
+CircleBuf::write(char b)
+{
+    write(&b, 1);
+}
+
+void
+CircleBuf::write(const char *b)
+{
+    write(b, strlen(b));
+}
+
+void
+CircleBuf::write(const char *b, int len)
+{
+    if (len <= 0)
+        return;
+
+    _size += len;
+    if (_size > _buflen)
+        _size = _buflen;
+
+    int old_start = _start;
+    int old_stop = _stop;
+
+    if (len >= _buflen) {
+        _start = 0;
+        _stop = _buflen;
+        _rollover = true;
+        memcpy(_buf, b + (len - _buflen), _buflen);
+        return;
+    }
+
+    if (_stop + len <= _buflen) {
+        memcpy(_buf + _stop, b, len);
+        _stop += len;
+    } else {
+        int end_len = _buflen - old_stop;
+        _stop = len - end_len;
+        memcpy(_buf + old_stop, b, end_len);
+        memcpy(_buf, b + end_len, _stop);
+        _rollover = true;
+    }
+
+    if ((old_start > old_stop && old_start < _stop) ||
+        (old_start < old_stop && _stop < old_stop))
+        _start = _stop + 1;
+}