/* NSC -- new scala compiler
* Copyright 2005 LAMP/EPFL
* @author Martin Odersky
*/
// $Id$
/* Ideas to extend this to an icode reader:
1. Parse classfile a second time, creating a hashmap `code' that associates method symbols with code.
2. For every method symbol `meth' in the new scope:
new = oldclass.info.decl(meth.name).suchThat(old => old.tpe =:= meth.tpe)
code(new) = code(meth)
*/
package scala.tools.nsc.symtab.classfile;
import scala.tools.nsc.util.Position;
import scala.tools.util.AbstractFile;
import scala.tools.util.AbstractFileReader;
import java.io.IOException;
abstract class ClassfileParser {
val global: Global;
import global._;
import ClassfileConstants._;
import Flags._;
private var in: AbstractFileReader = _; // the class file
private var clazz: Symbol = _; // the class symbol containing dynamic members
private var staticModule: Symbol = _; // the module symbol containing static members
private var instanceDefs: Scope = _; // the scope of all instance definitions
private var staticDefs: Scope = _; // the scope of all static definitions
private var pool: ConstantPool = _; // the classfile's constant pool
private var isScala: boolean = _; // does class file describe a scala class?
private var hasMeta: boolean = _; // does class file contain jaco meta attribute?s
private var busy: boolean = false; // lock to detect recursive reads
private object metaParser extends MetaParser {
val global: ClassfileParser.this.global.type = ClassfileParser.this.global
}
private object unpickler extends UnPickler {
val global: ClassfileParser.this.global.type = ClassfileParser.this.global
}
def parse(file: AbstractFile, root: Symbol): unit = {
assert(!busy);
busy = true;
this.in = new AbstractFileReader(file);
if (root.isModule) {
this.clazz = root.linkedClass;
this.staticModule = root
} else {
this.clazz = root;
this.staticModule = root.linkedModule
}
this.isScala = false;
this.hasMeta = false;
try {
parseHeader;
this.pool = new ConstantPool;
parseClass()
} catch {
case e: RuntimeException =>
if (settings.debug.value) e.printStackTrace();
throw new IOException("class file '" + in.file + "' is broken")
}
busy = false
}
private def statics: Symbol = staticModule.moduleClass;
private def parseHeader: unit = {
val magic = in.nextInt();
if (magic != JAVA_MAGIC)
throw new IOException("class file '" + in.file + "' "
+ "has wrong magic number 0x" + Integer.toHexString(magic)
+ ", should be 0x" + Integer.toHexString(JAVA_MAGIC));
val minorVersion = in.nextChar();
val majorVersion = in.nextChar();
if ((majorVersion < JAVA_MAJOR_VERSION) ||
((majorVersion == JAVA_MAJOR_VERSION) &&
(minorVersion < JAVA_MINOR_VERSION)))
throw new IOException("class file '" + in.file + "' "
+ "has unknown version "
+ majorVersion + "." + minorVersion
+ ", should be at least "
+ JAVA_MAJOR_VERSION + "." + JAVA_MINOR_VERSION);
}
class ConstantPool {
private val len = in.nextChar();
private val starts = new Array[int](len);
private val values = new Array[Object](len);
private val internalized = new Array[Name](len);
{ var i = 1;
while (i < starts.length) {
starts(i) = in.bp;
i = i + 1;
in.nextByte() match {
case CONSTANT_UTF8 | CONSTANT_UNICODE =>
in.skip(in.nextChar());
case CONSTANT_CLASS | CONSTANT_STRING =>
in.skip(2);
case CONSTANT_FIELDREF | CONSTANT_METHODREF | CONSTANT_INTFMETHODREF | CONSTANT_NAMEANDTYPE | CONSTANT_INTEGER | CONSTANT_FLOAT =>
in.skip(4);
case CONSTANT_LONG | CONSTANT_DOUBLE =>
in.skip(8);
i = i + 1
case _ =>
errorBadTag(in.bp - 1);
}
}
}
def getName(index: int): Name = {
if (index <= 0 || len <= index) errorBadIndex(index);
var name = values(index).asInstanceOf[Name];
if (name == null) {
val start = starts(index);
if (in.buf(start) != CONSTANT_UTF8) errorBadTag(start);
name = newTermName(in.buf, start + 3, in.getChar(start + 1));
values(index) = name;
}
name
}
def getExternalName(index: int): Name = {
if (index <= 0 || len <= index) errorBadIndex(index);
if (internalized(index) == null) {
internalized(index) = getName(index).replace('/', '.')
}
internalized(index)
}
def getClassSymbol(index: int): Symbol = {
if (index <= 0 || len <= index) errorBadIndex(index);
var c = values(index).asInstanceOf[Symbol];
if (c == null) {
val start = starts(index);
if (in.buf(start) != CONSTANT_CLASS) errorBadTag(start);
val name = getExternalName(in.getChar(start + 1));
c = definitions.getClass(name);
values(index) = c;
}
c
}
def getType(index: int): Type =
sigToType(getExternalName(index));
def getSuperClass(index: int): Symbol =
if (index == 0) definitions.AnyClass else getClassSymbol(index);
def getConstant(index: int): Constant = {
if (index <= 0 || len <= index) errorBadIndex(index);
var value = values(index);
if (value == null) {
val start = starts(index);
value = in.buf(start) match {
case CONSTANT_STRING =>
Constant(getName(in.getChar(start + 1)).toString())
case CONSTANT_INTEGER =>
Constant(in.getInt(start + 1))
case CONSTANT_FLOAT =>
Constant(in.getFloat(start + 1))
case CONSTANT_LONG =>
Constant(in.getLong(start + 1))
case CONSTANT_DOUBLE =>
Constant(in.getDouble(start + 1))
case _ =>
errorBadTag(start);
}
values(index) = value;
}
value.asInstanceOf[Constant]
}
/** Throws an exception signaling a bad constant index. */
private def errorBadIndex(index: int) =
throw new RuntimeException("bad constant pool index: " + index);
/** Throws an exception signaling a bad tag at given address. */
private def errorBadTag(start: int) =
throw new RuntimeException("bad constant pool tag " + in.buf(start) + " at byte " + start);
}
private def sigToType(name: Name): Type = {
var index = 0;
val end = name.length;
def objToAny(tp: Type): Type =
if (tp.symbol == definitions.ObjectClass) definitions.AnyClass.tpe
else tp;
def paramsigs2types: List[Type] =
if (name(index) == ')') { index = index + 1; List() }
else objToAny(sig2type) :: paramsigs2types;
def sig2type: Type = {
val tag = name(index); index = index + 1;
tag match {
case 'B' => definitions.ByteClass.tpe
case 'C' => definitions.CharClass.tpe
case 'D' => definitions.DoubleClass.tpe
case 'F' => definitions.FloatClass.tpe
case 'I' => definitions.IntClass.tpe
case 'J' => definitions.LongClass.tpe
case 'S' => definitions.ShortClass.tpe
case 'V' => definitions.UnitClass.tpe
case 'Z' => definitions.BooleanClass.tpe
case 'L' =>
val start = index;
while (name(index) != ';') { index = index + 1 }
val end = index;
index = index + 1;
definitions.getClass(name.subName(start, end)).tpe
case '[' =>
while ('0' <= name(index) && name(index) <= '9') index = index + 1;
appliedType(definitions.ArrayClass.tpe, List(sig2type))
case '(' =>
JavaMethodType(paramsigs2types, sig2type)
}
}
sig2type
}
def parseClass(): unit = {
val jflags = in.nextChar();
var sflags = transFlags(jflags);
if ((sflags & DEFERRED) != 0) sflags = sflags & ~DEFERRED | ABSTRACT;
val c = pool.getClassSymbol(in.nextChar());
if (c != clazz)
throw new IOException("class file '" + in.file + "' contains wrong " + clazz);
val superType = pool.getSuperClass(in.nextChar()).tpe;
val ifaceCount = in.nextChar();
val parents = (superType ::
(for (val i <- List.range(0, ifaceCount))
yield pool.getSuperClass(in.nextChar()).tpe));
instanceDefs = new Scope();
staticDefs = new Scope();
val classInfo = ClassInfoType(parents, instanceDefs, clazz);
val staticInfo = ClassInfoType(List(), staticDefs, statics);
val curbp = in.bp;
skipMembers(); // fields
skipMembers(); // methods
parseAttributes(clazz, classInfo);
if (!isScala) {
clazz.setFlag(sflags);
if (!hasMeta) {
clazz.setInfo(classInfo);
}
statics.setInfo(staticInfo);
staticModule.setInfo(statics.tpe);
staticModule.setFlag(JAVA);
staticModule.moduleClass.setFlag(JAVA);
in.bp = curbp;
val fieldCount = in.nextChar();
for (val i <- Iterator.range(0, fieldCount)) parseField();
val methodCount = in.nextChar();
for (val i <- Iterator.range(0, methodCount)) parseMethod();
if (instanceDefs.lookup(nme.CONSTRUCTOR) == NoSymbol && (sflags & INTERFACE) == 0) {
//System.out.println("adding constructor to " + clazz);//DEBUG
instanceDefs.enter(
clazz.newConstructor(Position.NOPOS)
.setFlag(clazz.flags & ConstrFlags).setInfo(MethodType(List(), clazz.tpe)));
}
}
}
def parseField(): unit = {
val jflags = in.nextChar();
var sflags = transFlags(jflags);
if ((sflags & FINAL) == 0) sflags = sflags | MUTABLE;
if ((sflags & PRIVATE) != 0) {
in.skip(4); skipAttributes();
} else {
val name = pool.getName(in.nextChar());
val info = pool.getType(in.nextChar());
val sym = getOwner(jflags)
.newValue(Position.NOPOS, name).setFlag(sflags).setInfo(info);
parseAttributes(sym, info);
getScope(jflags).enter(sym);
}
}
def parseMethod(): unit = {
val jflags = in.nextChar();
var sflags = transFlags(jflags);
if ((jflags & JAVA_ACC_BRIDGE) != 0) sflags = sflags | PRIVATE;
if ((sflags & PRIVATE) != 0) {
in.skip(4); skipAttributes();
} else {
val name = pool.getName(in.nextChar());
var info = pool.getType(in.nextChar());
if (name == nme.CONSTRUCTOR)
info match {
case MethodType(formals, restpe) =>
assert(restpe.symbol == definitions.UnitClass);
info = MethodType(formals, clazz.tpe)
}
val sym = getOwner(jflags)
.newMethod(Position.NOPOS, name).setFlag(sflags).setInfo(info);
parseAttributes(sym, info);
getScope(jflags).enter(sym);
}
}
def parseAttributes(sym: Symbol, symtype: Type): unit = {
def parseAttribute(): unit = {
val attrName = pool.getName(in.nextChar());
val attrLen = in.nextInt();
attrName match {
case nme.SyntheticATTR =>
sym.setFlag(SYNTHETIC);
in.skip(attrLen)
case nme.BridgeATTR =>
sym.setFlag(BRIDGE);
in.skip(attrLen)
case nme.DeprecatedATTR =>
sym.setFlag(DEPRECATED);
in.skip(attrLen)
case nme.ConstantValueATTR =>
val c = pool.getConstant(in.nextChar());
val c1 = c convertTo symtype;
sym.setInfo(ConstantType(c1));
case nme.InnerClassesATTR =>
parseInnerClasses()
case nme.ScalaSignatureATTR =>
unpickler.unpickle(in.buf, in.bp, clazz, staticModule);
this.isScala = true;
case nme.JacoMetaATTR =>
val meta = pool.getName(in.nextChar()).toString().trim();
metaParser.parse(meta, sym, symtype);
this.hasMeta = true;
case _ =>
in.skip(attrLen)
}
}
def parseInnerClasses(): unit = {
for (val i <- Iterator.range(0, in.nextChar())) {
val innerIndex = in.nextChar();
val outerIndex = in.nextChar();
val nameIndex = in.nextChar();
val jflags = in.nextChar();
if (innerIndex != 0 && outerIndex != 0 && nameIndex != 0 &&
(jflags & (JAVA_ACC_PUBLIC | JAVA_ACC_PROTECTED)) != 0 &&
pool.getClassSymbol(outerIndex) == sym) {
val innerAlias = getOwner(jflags)
.newAliasType(Position.NOPOS, pool.getName(nameIndex).toTypeName)
.setInfo(pool.getClassSymbol(innerIndex).tpe);
getScope(jflags).enter(innerAlias);
}
}
}
val attrCount = in.nextChar();
for (val i <- Iterator.range(0, attrCount)) parseAttribute()
}
def skipAttributes(): unit = {
val attrCount = in.nextChar();
for (val i <- Iterator.range(0, attrCount)) {
in.skip(2); in.skip(in.nextInt())
}
}
def skipMembers(): unit = {
val memberCount = in.nextChar();
for (val i <- Iterator.range(0, memberCount)) {
in.skip(6); skipAttributes()
}
}
private def getOwner(flags: int): Symbol =
if ((flags & JAVA_ACC_STATIC) != 0) statics else clazz;
private def getScope(flags: int): Scope =
if ((flags & JAVA_ACC_STATIC) != 0) staticDefs else instanceDefs;
private def transFlags(flags: int): long = {
var res = 0l;
if ((flags & JAVA_ACC_PRIVATE) != 0)
res = res | PRIVATE
else if ((flags & JAVA_ACC_PROTECTED) != 0)
res = res | PROTECTED
else if ((flags & JAVA_ACC_PUBLIC) == 0)
res = res | PRIVATE;
if ((flags & JAVA_ACC_ABSTRACT) != 0)
res = res | DEFERRED;
if ((flags & JAVA_ACC_FINAL) != 0)
res = res | FINAL;
if ((flags & JAVA_ACC_INTERFACE) != 0)
res = res | MIXIN | INTERFACE | ABSTRACT;
if ((flags & JAVA_ACC_SYNTHETIC) != 0)
res = res | SYNTHETIC;
if ((flags & JAVA_ACC_STATIC) != 0)
res = res | STATIC;
res | JAVA;
}
}