feat: initial implementation, created interface and moved stuff from processor

6 files changed, 338 insertions, 0 deletions

diff --git a/src/main/java/ftbsc/lll/exceptions/AmbiguousMappingException.java b/src/main/java/ftbsc/lll/exceptions/AmbiguousMappingException.java
new file mode 100644
index 0000000..794759a
--- /dev/null
+++ b/src/main/java/ftbsc/lll/exceptions/AmbiguousMappingException.java
@@ -0,0 +1,27 @@
+package ftbsc.lll.exceptions;
+
+import ftbsc.lll.mapper.IMapper;
+
+/**
+ * Thrown when a given {@link IMapper} cannot uniquely identify a mapping with
+ * the given data.
+ */
+public class AmbiguousMappingException extends RuntimeException {
+
+	/**
+	 * Constructs a new ambiguous mapping definition exception with the specified detail message.
+	 * @param message the detail message
+	 */
+	public AmbiguousMappingException(String message) {
+		super(message);
+	}
+
+	/**
+	 * Constructs a new ambiguous definition exception with the specified detail message and cause.
+	 * @param  message the detail message
+	 * @param  cause the cause, may be null (indicating nonexistent or unknown cause)
+	 */
+	public AmbiguousMappingException(String message, Throwable cause) {
+		super(message, cause);
+	}
+}
\ No newline at end of file
diff --git a/src/main/java/ftbsc/lll/exceptions/MappingNotFoundException.java b/src/main/java/ftbsc/lll/exceptions/MappingNotFoundException.java
new file mode 100644
index 0000000..6c286fc
--- /dev/null
+++ b/src/main/java/ftbsc/lll/exceptions/MappingNotFoundException.java
@@ -0,0 +1,27 @@
+package ftbsc.lll.exceptions;
+
+import ftbsc.lll.mapper.IMapper;
+
+/**
+ * Thrown upon failure to find the requested mapping within a loaded {@link IMapper}.
+ */
+public class MappingNotFoundException extends RuntimeException {
+
+	/**
+	 * Constructs a new mapping not found exception for the specified mapping.
+	 * @param mapping the relevant mapping
+	 */
+	public MappingNotFoundException(String mapping) {
+		super(String.format("Could not find mapping for %s!", mapping));
+	}
+
+	/**
+	 * Constructs a new mapping not found exception for the specified mapping
+	 * with the specified reason.
+	 * @param mapping the relevant mapping
+	 * @param reason the reason message
+	 */
+	public MappingNotFoundException(String mapping, String reason) {
+		this(mapping + ": " + reason);
+	}
+}
diff --git a/src/main/java/ftbsc/lll/mapper/IMapper.java b/src/main/java/ftbsc/lll/mapper/IMapper.java
new file mode 100644
index 0000000..8adf860
--- /dev/null
+++ b/src/main/java/ftbsc/lll/mapper/IMapper.java
@@ -0,0 +1,56 @@
+package ftbsc.lll.mapper;
+
+import ftbsc.lll.exceptions.MappingNotFoundException;
+
+import java.util.HashSet;
+import java.util.ServiceLoader;
+import java.util.Set;
+
+/**
+ * A generic obfuscation mapper.
+ */
+public interface IMapper {
+
+	/**
+	 * Reads the given lines of text and attempts to interpret them as
+	 * mappings of the given type.
+	 * @param lines the lines to read
+	 */
+	void populate(Iterable<String> lines);
+
+	/**
+	 * Gets the obfuscated name of the class.
+	 * @param name the unobfuscated internal name of the desired class
+	 * @return the obfuscated name of the class
+	 * @throws MappingNotFoundException if no mapping is found
+	 */
+	String obfuscateClass(String name);
+
+	/**
+	 * Gets the obfuscated name of a class member (field or method).
+	 * @param parentName the unobfuscated internal name of the parent class
+	 * @param memberName the field name or method signature
+	 * @param methodDescriptor the descriptor of the member
+	 * @return the obfuscated name of the given member
+	 * @throws MappingNotFoundException if no mapping is found
+	 */
+	String obfuscateMember(String parentName, String memberName, String methodDescriptor);
+
+	/**
+	 * Loads all valid parsers available in the classpath (via the Java Service API),
+	 * attempts to parse the given lines into mappings, and returns all built mappers
+	 * that succeeded without throwing errors or ftbsc.lll.exceptions.
+	 * @param lines the lines of the mapping file
+	 * @return a {@link Set} of mappers that could interpret the given input
+	 */
+	static Set<IMapper> getMappers(Iterable<String> lines) {
+		Set<IMapper> parsed = new HashSet<>();
+		for(IMapper mapper: ServiceLoader.load(IMapper.class)) {
+			try {
+				mapper.populate(lines);
+				parsed.add(mapper);
+			} catch(Throwable ignored) {}
+		}
+		return parsed;
+	}
+}
diff --git a/src/main/java/ftbsc/lll/mapper/impl/TSRGMapper.java b/src/main/java/ftbsc/lll/mapper/impl/TSRGMapper.java
new file mode 100644
index 0000000..0fc6489
--- /dev/null
+++ b/src/main/java/ftbsc/lll/mapper/impl/TSRGMapper.java
@@ -0,0 +1,72 @@
+package ftbsc.lll.mapper.impl;
+
+import ftbsc.lll.exceptions.MappingNotFoundException;
+import ftbsc.lll.mapper.IMapper;
+import ftbsc.lll.mapper.tools.ClassData;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Parses a .tsrg file into a mapper capable of converting from
+ * plain names to obfuscated ones and vice versa.
+ */
+public class TSRGMapper implements IMapper {
+
+	/**
+	 * A Map containing the deobfuscated names as keys and information about
+	 * each class as values.
+	 */
+	private final Map<String, ClassData> mappings = new HashMap<>();
+
+	/**
+	 * Reads the given lines of text and attempts to interpret them as
+	 * mappings of the given type.
+	 * @param lines the lines to read
+	 */
+	@Override
+	public void populate(Iterable<String> lines) {
+		String currentClass = "";
+		for(String l : lines) {
+			if(l == null) continue;
+			if(l.startsWith("\t"))
+				mappings.get(currentClass).addMember(l);
+			else {
+				String[] sp = l.split(" ");
+				ClassData s = new ClassData(sp[0], sp[1]);
+				currentClass = s.unobf;
+				mappings.put(s.unobf, s);
+			}
+		}
+	}
+
+	/**
+	 * Gets the obfuscated name of the class.
+	 * @param name the unobfuscated internal name of the desired class
+	 * @return the obfuscated name of the class
+	 * @throws MappingNotFoundException if no mapping is found
+	 */
+	@Override
+	public String obfuscateClass(String name)  {
+		ClassData data = mappings.get(name.replace('.', '/'));
+		if(data == null)
+			throw new MappingNotFoundException(name);
+		else return data.obf;
+	}
+
+	/**
+	 * Gets the obfuscated name of a class member (field or method).
+	 * @param parentName the unobfuscated internal name of the parent class
+	 * @param memberName the field name or method signature
+	 * @param methodDescriptor the optional descriptor of the member, may be null or partial
+	 * @return the obfuscated name of the given member
+	 * @throws MappingNotFoundException if no mapping is found
+	 */
+	@Override
+	public String obfuscateMember(String parentName, String memberName, String methodDescriptor) {
+		ClassData data = mappings.get(parentName.replace('.', '/'));
+		if(data == null)
+			throw new MappingNotFoundException(parentName + "::" + memberName);
+		return data.get(memberName, methodDescriptor);
+	}
+}
diff --git a/src/main/java/ftbsc/lll/mapper/tools/ClassData.java b/src/main/java/ftbsc/lll/mapper/tools/ClassData.java
new file mode 100644
index 0000000..a9fbcec
--- /dev/null
+++ b/src/main/java/ftbsc/lll/mapper/tools/ClassData.java
@@ -0,0 +1,100 @@
+package ftbsc.lll.mapper.tools;
+
+import ftbsc.lll.exceptions.AmbiguousMappingException;
+import ftbsc.lll.exceptions.MappingNotFoundException;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+/**
+ * Container class used to store information about classes.
+ */
+public class ClassData {
+	/**
+	 * The unobfuscated name (FQN with '/' instad of '.') of the class.
+	 */
+	public final String unobf;
+
+	/**
+	 * The obfuscated internal name (FQN with '/' instad of '.') of the class.
+	 */
+	public final String obf;
+
+	/**
+	 * A {@link Map} tying each member's name or signature to its
+	 * obfuscated counterpart.
+	 */
+	public final Map<String, String> members;
+
+	/**
+	 * The constructor. It takes in the names (obfuscated and non-obfuscated)
+	 * of a class.
+	 * @param unobf the unobfuscated name
+	 * @param obf the obfuscated name
+	 */
+	public ClassData(String unobf, String obf) {
+		this.unobf = unobf;
+		this.obf = obf;
+		this.members = new HashMap<>();
+	}
+
+	/**
+	 * Adds a member to the target class.
+	 * For fields only the names are required; for methods,
+	 * this takes in the full signature ({@code name + " " + space}).
+	 * @param s the String representing the declaration line
+	 */
+	public void addMember(String s) {
+		String[] split = s.trim().split(" ");
+		if(split.length == 2) //field
+			members.put(split[0], split[1]);
+		else if (split.length == 3) //method
+			members.put(split[0] + " " + split[1], split[2]);
+	}
+
+	/**
+	 * Gets an obfuscated member given the method name and a method descriptor,
+	 * which may be partial (i.e. not include return type) or null if the member
+	 * is not a method.
+	 * @param memberName member name
+	 * @param methodDescriptor the method descriptor, or null if it's not a method
+	 * @return the requested obfuscated name, or null if nothing was found
+	 * @throws AmbiguousMappingException if not enough data was given to uniquely identify a mapping
+	 */
+	public String get(String memberName, String methodDescriptor) {
+
+		//find all keys that start with the name
+		List<String> candidates = members.keySet().stream().filter(
+			m -> m.split(" ")[0].equals(memberName)
+		).collect(Collectors.toList());
+
+		if(methodDescriptor != null) {
+			String signature = String.format("%s %s", memberName, methodDescriptor);
+			candidates = candidates.stream().filter(
+				m -> m.equals(signature)
+			).collect(Collectors.toList());
+		}
+
+		switch(candidates.size()) {
+			case 0:
+				throw new MappingNotFoundException(String.format(
+					"%s.%s%s",
+					this.unobf,
+					memberName,
+					methodDescriptor == null ? "" : "()"
+				));
+			case 1:
+				return members.get(candidates.get(0));
+			default:
+				throw new AmbiguousMappingException(String.format(
+					"Mapper could not uniquely identify member %s.%s%s, found %d!",
+					this.unobf,
+					memberName,
+					methodDescriptor == null ? "" : "()",
+					candidates.size()
+				));
+		}
+	}
+}
\ No newline at end of file
diff --git a/src/main/java/ftbsc/lll/mapper/tools/MappingUtils.java b/src/main/java/ftbsc/lll/mapper/tools/MappingUtils.java
new file mode 100644
index 0000000..918052a
--- /dev/null
+++ b/src/main/java/ftbsc/lll/mapper/tools/MappingUtils.java
@@ -0,0 +1,56 @@
+package ftbsc.lll.mapper.tools;
+
+import ftbsc.lll.exceptions.MappingNotFoundException;
+import ftbsc.lll.mapper.IMapper;
+import ftbsc.lll.tools.DescriptorBuilder;
+import org.objectweb.asm.Type;
+
+public class MappingUtils {
+	/**
+	 * Obfuscates a method descriptor, replacing its class references
+	 * with their obfuscated counterparts.
+	 * @param descriptor a {@link String} containing the descriptor
+	 * @return the obfuscated descriptor
+	 */
+	public static String obfuscateMethodDescriptor(String descriptor, IMapper mapper) {
+		Type method = Type.getMethodType(descriptor);
+		Type[] arguments = method.getArgumentTypes();
+		Type returnType = method.getReturnType();
+
+		Type[] obfArguments = new Type[arguments.length];
+		for(int i = 0; i < obfArguments.length; i++)
+			obfArguments[i] = obfuscateType(arguments[i], mapper);
+
+		return Type.getMethodDescriptor(obfuscateType(returnType, mapper), obfArguments);
+	}
+
+	/**
+	 * Given a {@link Type} and a valid {@link IMapper} it returns its obfuscated
+	 * counterpart.
+	 * @param type the type in question
+	 * @return the obfuscated type
+	 */
+	public static Type obfuscateType(Type type, IMapper mapper) {
+		//unwrap arrays
+		Type unwrapped = type;
+		int arrayLevel = 0;
+		while(unwrapped.getSort() == Type.ARRAY) {
+			unwrapped = unwrapped.getElementType();
+			arrayLevel++;
+		}
+
+		//if it's a primitive no operation is needed
+		if(type.getSort() < Type.ARRAY)
+			return type;
+
+		String internalName = type.getInternalName();
+
+		String internalNameObf;
+		try {
+			internalNameObf = mapper.obfuscateClass(internalName);
+			return Type.getType(DescriptorBuilder.nameToDescriptor(internalNameObf, arrayLevel));
+		} catch(MappingNotFoundException e) {
+			return type;
+		}
+	}
+}