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package jdk.tools.jaotc.binformat.macho;

import java.nio.ByteBuffer;
import java.util.ArrayList;

import jdk.tools.jaotc.binformat.macho.MachO.nlist_64;
import jdk.tools.jaotc.binformat.macho.MachO.symtab_command;

final class MachOSymtab {

    
ByteBuffer holding the LC_SYMTAB command contents.
/** * ByteBuffer holding the LC_SYMTAB command contents. */
private final ByteBuffer symtabCmd; private int symtabDataSize; private final ArrayList<MachOSymbol> localSymbols = new ArrayList<>(); private final ArrayList<MachOSymbol> globalSymbols = new ArrayList<>(); private final ArrayList<MachOSymbol> undefSymbols = new ArrayList<>();
Number of symbols added.
/** * Number of symbols added. */
private int symbolCount;
String holding symbol table strings.
/** * String holding symbol table strings. */
private final StringBuilder strTabContent = new StringBuilder();
Keeps track of bytes in string table since strTabContent.length() is number of chars, not bytes.
/** * Keeps track of bytes in string table since strTabContent.length() is number of chars, not * bytes. */
private int strTabNrOfBytes = 0; MachOSymtab() { symtabCmd = MachOByteBuffer.allocate(symtab_command.totalsize); symtabCmd.putInt(symtab_command.cmd.off, symtab_command.LC_SYMTAB); symtabCmd.putInt(symtab_command.cmdsize.off, symtab_command.totalsize); symbolCount = 0; } static int getAlign() { return (4); } MachOSymbol addSymbolEntry(String name, byte type, byte secHdrIndex, long offset) { // Get the current symbol index and append symbol name to string table. int index; MachOSymbol sym; if (name.isEmpty()) { index = 0; strTabContent.append('\0'); strTabNrOfBytes += 1; sym = new MachOSymbol(symbolCount, index, type, secHdrIndex, offset); localSymbols.add(sym); } else { // We can't trust strTabContent.length() since that is // chars (UTF16), keep track of bytes on our own. index = strTabNrOfBytes; strTabContent.append("_").append(name).append('\0'); // + 1 for null, + 1 for "_" strTabNrOfBytes += (name.getBytes().length + 1 + 1); sym = new MachOSymbol(symbolCount, index, type, secHdrIndex, offset); switch (type) { case nlist_64.N_EXT: undefSymbols.add(sym); break; case nlist_64.N_SECT: case nlist_64.N_UNDF: // null symbol localSymbols.add(sym); break; case nlist_64.N_SECT | nlist_64.N_EXT: globalSymbols.add(sym); break; default: System.out.println("Unsupported Symbol type " + type); break; } } symbolCount++; return (sym); } void setOffset(int symoff) { symtabCmd.putInt(symtab_command.symoff.off, symoff); } // Update the symbol indexes once all symbols have been added. // This is required since we'll be reordering the symbols in the // file to be in the order of Local, global and Undefined. void updateIndexes() { int index = 0; // Update the local symbol indexes for (int i = 0; i < localSymbols.size(); i++) { MachOSymbol sym = localSymbols.get(i); sym.setIndex(index++); } // Update the global symbol indexes for (int i = 0; i < globalSymbols.size(); i++) { MachOSymbol sym = globalSymbols.get(i); sym.setIndex(index++); } // Update the undefined symbol indexes for (int i = index; i < undefSymbols.size(); i++) { MachOSymbol sym = undefSymbols.get(i); sym.setIndex(index++); } } // Update LC_SYMTAB command fields based on the number of symbols added // return the file size taken up by symbol table entries and strings int calcSizes() { int stroff; stroff = symtabCmd.getInt(symtab_command.symoff.off) + (nlist_64.totalsize * symbolCount); symtabCmd.putInt(symtab_command.nsyms.off, symbolCount); symtabCmd.putInt(symtab_command.stroff.off, stroff); symtabCmd.putInt(symtab_command.strsize.off, strTabNrOfBytes); symtabDataSize = (nlist_64.totalsize * symbolCount) + strTabNrOfBytes; return (symtabDataSize); } int getNumLocalSyms() { return localSymbols.size(); } int getNumGlobalSyms() { return globalSymbols.size(); } int getNumUndefSyms() { return undefSymbols.size(); } byte[] getCmdArray() { return symtabCmd.array(); } // Create a single byte array that contains the symbol table entries // and string table byte[] getDataArray() { ByteBuffer symtabData = MachOByteBuffer.allocate(symtabDataSize); byte[] retarray; // Add the local symbols for (int i = 0; i < localSymbols.size(); i++) { MachOSymbol sym = localSymbols.get(i); byte[] arr = sym.getArray(); symtabData.put(arr); } // Add the global symbols for (int i = 0; i < globalSymbols.size(); i++) { MachOSymbol sym = globalSymbols.get(i); byte[] arr = sym.getArray(); symtabData.put(arr); } // Add the undefined symbols for (int i = 0; i < undefSymbols.size(); i++) { MachOSymbol sym = undefSymbols.get(i); byte[] arr = sym.getArray(); symtabData.put(arr); } // Add the stringtable byte[] strs = strTabContent.toString().getBytes(); symtabData.put(strs); retarray = symtabData.array(); return (retarray); } }