src/hotspot/share/prims/jvmtiEnvFill.java

/*
 * Copyright (c) 2003, 2022, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

import java.io.*;
import java.util.*;

class jvmtiEnvFill {

    public static void main(String[] args) throws IOException {
        if (args.length != 3) {
            System.err.println("usage: <filledFile> <stubFile> <resultFile>");
            System.exit(1);
        }
        String filledFN = args[0];
        String stubFN = args[1];
        String resultFN = args[2];

        SourceFile filledSF = new SourceFile(filledFN);
        SourceFile stubSF = new SourceFile(stubFN);


        stubSF.fill(filledSF);

        PrintWriter out = new PrintWriter(new FileWriter(resultFN));
        stubSF.output(out);
        out.close();
    }
}

class SourceFile {

    static final String endFilePrefix = "// end file prefix";
    static final String functionPrefix = "JvmtiEnv::";

    final String fn;
    LineNumberReader in;
    String line;
    List<String> top = new ArrayList<String>();
    List<String> before = new ArrayList<String>();
    boolean inFilePrefix = true;
    List<Function> functions = new ArrayList<Function>();
    Map<String, Function> functionMap = new HashMap<String, Function>();

    class Function {
      String name;
      String args;
      String compareArgs;
      List comment;
      List<String> body = new ArrayList<String>();

      Function() throws IOException {
        line = in.readLine();
        String trimmed = line.trim();
        if (!trimmed.startsWith(functionPrefix)) {
            error("expected '" + functionPrefix + "'");
        }
        int index = trimmed.indexOf('(', functionPrefix.length());
        if (index == -1) {
            error("missing open paren");
        }
        name = trimmed.substring(functionPrefix.length(), index);
        int index2 = trimmed.indexOf(')', index);
        if (index2 == -1) {
            error("missing close paren - must be on same line");
        }
        args = trimmed.substring(index+1, index2);
        compareArgs = args.replaceAll("\\s", "");
        String tail = trimmed.substring(index2+1).trim();
        if (!tail.equals("{")) {
            error("function declaration first line must end with open bracket '{', instead got '" +
                   tail + "'");
        }
        while(true) {
            line = in.readLine();
            if (line == null) {
                line = ""; // so error does not look weird
                error("unexpected end of file");
            }
            if (line.startsWith("}")) {
                break;
            }
            body.add(line);
        }
        String expected = "} /* end " + name + " */";
        trimmed = line.replaceAll("\\s","");
        if (!trimmed.equals(expected.replaceAll("\\s",""))) {
            error("function end is malformed - should be: " + expected);
        }
        // copy over the comment prefix
        comment = before;
        before = new ArrayList<String>();
      }

      void remove() {
        functionMap.remove(name);
      }

      String fileName() {
        return fn;
      }

      void fill(Function filledFunc) {
        if (filledFunc == null) {
            System.err.println("Warning: function " + name + " missing from filled file");
            body.add(0, "    /*** warning: function added and not filled in ***/");
        } else {
            int fbsize = filledFunc.body.size();
            int bsize = body.size();
            if (fbsize > bsize  || !body.subList(bsize-fbsize,bsize).equals(filledFunc.body)) {
                // it has actually been filled in
                body = filledFunc.body;
                if (!compareArgs.equals(filledFunc.compareArgs)) {
                    System.err.println("Warning: function " + name +
                                       ": filled and stub arguments differ");
                    System.err.println("  old (filled): " + filledFunc.args);
                    System.err.println("  new (stub): " + args);
                    body.add(0, "    /*** warning: arguments changed, were: " +
                             filledFunc.args + " ***/");
                }
            }
            filledFunc.remove();  // mark used
        }
      }

      void output(PrintWriter out) {
            Iterator it = comment.iterator();
            while (it.hasNext()) {
                out.println(it.next());
            }
            out.println("jvmtiError");
            out.print(functionPrefix);
            out.print(name);
            out.print('(');
            out.print(args);
            out.println(") {");
            it = body.iterator();
            while (it.hasNext()) {
                out.println(it.next());
            }
            out.print("} /* end ");
            out.print(name);
            out.println(" */");
      }
    }

    SourceFile(String fn) throws IOException {
        this.fn = fn;
        Reader reader = new FileReader(fn);
        in = new LineNumberReader(reader);

        while (readGaps()) {
            Function func = new Function();
            functionMap.put(func.name, func);
            functions.add(func);
        }

        in.close();
    }

    void error(String msg) {
        System.err.println("Fatal error parsing file: " + fn);
        System.err.println("Line number: " + in.getLineNumber());
        System.err.println("Error message: " + msg);
        System.err.println("Source line: " + line);
        System.exit(1);
    }

    boolean readGaps() throws IOException {
        while(true) {
            line = in.readLine();
            if (line == null) {
                return false; // end of file
            }
            if (!inFilePrefix && line.startsWith("}")) {
                error("unexpected close bracket in first column, outside of function.\n");
            }
            String trimmed = line.trim();
            if (line.startsWith("jvmtiError")) {
                if (trimmed.equals("jvmtiError")) {
                    if (inFilePrefix) {
                        error("unexpected 'jvmtiError' line in file prefix.\n" +
                              "is '" + endFilePrefix + "'... line missing?");
                    }
                    return true; // beginning of a function
                } else {
                    error("extra characters at end of 'jvmtiError'");
                }
            }
            if (inFilePrefix) {
                top.add(line);
            } else {
                trimmed = line.trim();
                if (!trimmed.equals("") && !trimmed.startsWith("//") && !trimmed.startsWith("#")) {
                    error("only comments and blank lines allowed between functions");
                }
                before.add(line);
            }
            if (line.replaceAll("\\s","").toLowerCase().startsWith(endFilePrefix.replaceAll("\\s",""))) {
                if (!inFilePrefix) {
                    error("excess '" + endFilePrefix + "'");
                }
                inFilePrefix = false;
            }
        }
    }

    void fill(SourceFile filledSF) {
        // copy beginning of file straight from filled file
        top = filledSF.top;

        // file in functions
        Iterator it = functions.iterator();
        while (it.hasNext()) {
            Function stubFunc = (Function)(it.next());
            Function filledFunc = (Function)filledSF.functionMap.get(stubFunc.name);
            stubFunc.fill(filledFunc);
        }
        if (filledSF.functionMap.size() > 0) {
            System.err.println("Warning: the following functions were present in the " +
                                "filled file but missing in the stub file and thus not copied:");
            it  = filledSF.functionMap.values().iterator();
            while (it.hasNext()) {
                System.err.println("        " + ((Function)(it.next())).name);
            }
        }
    }

    void output(PrintWriter out) {
        Iterator it = top.iterator();
        while (it.hasNext()) {
            out.println(it.next());
        }
        it = functions.iterator();
        while (it.hasNext()) {
            Function stubFunc = (Function)(it.next());
            stubFunc.output(out);
        }
    }
}