minij.assembler.Assembler.java Source code

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Here is the source code for minij.assembler.Assembler.java

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/*
 * MiniJCompiler: Compiler for a subset of the Java(R) language
 *
 * (C) Copyright 2014-2015 Tibor Goldschwendt <goldschwendt@cip.ifi.lmu.de>,
 * Michael Seifert <mseifert@error-reports.org>
 *
 * This file is part of MiniJCompiler.
 *
 * MiniJCompiler is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * MiniJCompiler is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with MiniJCompiler.  If not, see <http://www.gnu.org/licenses/>.
 */
package minij.assembler;

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;

import minij.Configuration;
import minij.Logger;
import minij.MiniJCompiler;

import org.apache.commons.io.FilenameUtils;

public class Assembler {

    public static void assemble(Configuration config, String assembly) throws AssemblerException {

        try {
            new File(FilenameUtils.getPath(config.outputFile)).mkdirs();

            // -xc specifies the input language as C and is required for GCC to read from stdin
            ProcessBuilder processBuilder = new ProcessBuilder("gcc", "-o", config.outputFile, "-m32", "-xc",
                    MiniJCompiler.RUNTIME_DIRECTORY.toString() + File.separator + "runtime_32.c", "-m32",
                    "-xassembler", "-");
            Process gccCall = processBuilder.start();
            // Write C code to stdin of C Compiler
            OutputStream stdin = gccCall.getOutputStream();
            stdin.write(assembly.getBytes());
            stdin.close();

            gccCall.waitFor();

            // Print error messages of GCC
            if (gccCall.exitValue() != 0) {

                StringBuilder errOutput = new StringBuilder();
                InputStream stderr = gccCall.getErrorStream();
                String line;
                BufferedReader bufferedStderr = new BufferedReader(new InputStreamReader(stderr));
                while ((line = bufferedStderr.readLine()) != null) {
                    errOutput.append(line + System.lineSeparator());
                }
                bufferedStderr.close();
                stderr.close();

                throw new AssemblerException(
                        "Failed to compile assembly:" + System.lineSeparator() + errOutput.toString());
            }

            Logger.logVerbosely("Successfully compiled assembly");
        } catch (IOException e) {
            throw new AssemblerException("Failed to transfer assembly to gcc", e);
        } catch (InterruptedException e) {
            throw new AssemblerException("Failed to invoke gcc", e);
        }

    }

}