util/m5/src/command/readfile.cc

/*
 * Copyright (c) 2003-2005 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.
 */

#include <cstring>
#include <iostream>

#include "args.hh"
#include "command.hh"
#include "dispatch_table.hh"

namespace
{

int
read_file(const DispatchTable &dt, std::ostream &os)
{
    char buf[256 * 1024];

    // Touch all buffer pages to ensure they are mapped in the
    // page table. This is required in the case of X86_FS, where
    // Linux does demand paging.
    std::memset(buf, 0, sizeof(buf));

    int len;
    int offset = 0;
    while ((len = (*dt.m5_read_file)(buf, sizeof(buf), offset)) > 0) {
        os.write(buf, len);
        os.flush();
        if (!os) {
            std::cerr << "Failed to write file" << std::endl;
            exit(2);
        }
        offset += len;
    }

    return offset;
}

bool
do_read_file(const DispatchTable &dt, Args &args)
{
    if (args.size() > 0)
        return false;

    read_file(dt, std::cout);

    return true;
}

Command read_file_cmd = {
    "readfile", 0, 0, do_read_file, "\n"
        "        read a preselected file from the host and write it to "
            "stdout" };

} // anonymous namespace