- Added Positon and SourceFile in scala/tools/util

2 files changed, 347 insertions, 0 deletions

diff --git a/sources/scala/tools/util/Position.java b/sources/scala/tools/util/Position.java
new file mode 100644
index 0000000000..9afdc78e7c
--- /dev/null
+++ b/sources/scala/tools/util/Position.java
@@ -0,0 +1,170 @@
+/*     ____ ____  ____ ____  ______                                     *\
+**    / __// __ \/ __// __ \/ ____/    SOcos COmpiles Scala             **
+**  __\_ \/ /_/ / /__/ /_/ /\_ \       (c) 2002, LAMP/EPFL              **
+** /_____/\____/\___/\____/____/                                        **
+\*                                                                      */
+
+// $Id$
+
+package scala.tools.util;
+
+/**
+ * This class represents a position in a source file. Such a position
+ * is defined by a source file (mandatory), a line number (optional)
+ * and a column number (optional, may be specified only if the line
+ * number is defined).
+ *
+ * Line (Column) numbers range from 0 to Integer.MAX_VALUE. A value of
+ * 0 indicates that the line (column) is undefined, 1 represents the
+ * first line (column). Negative values are prohibited.
+ *
+ * The class provides also functions to encode a line number and a
+ * column number into one single integer. The encode line (column)
+ * numbers range from 0 to LINE_MASK (COLUMN_MASK), where 0 indicates
+ * that the line (column) is the undefined and 1 represents the first
+ * line (column). Line (Column) numbers greater than LINE_MASK
+ * (COLUMN_MASK) are replaced by LINE_MASK (COLUMN_MASK). Furthermore,
+ * if the encoded line number is LINE_MASK, the column number is
+ * always set to 0.
+ *
+ * The following properties hold:
+ * - the undefined position is 0: encode(0,0) == 0
+ * - encodings are non-negative : encode(line,column) >= 0
+ * - position order is preserved:
+ *   (line1 < line2) || (line1 == line2 && column1 < column2)
+ * implies
+ *   encode(line1,column1) <= encode(line2,column2)
+ */
+public class Position {
+
+    //########################################################################
+    // Public Constants
+
+    /** Number of bits used to encode the line number */
+    public static final int LINE_BITS   = 20;
+    /** Number of bits used to encode the column number */
+    public static final int COLUMN_BITS = 31 - LINE_BITS; // no negatives => 31
+
+    /** Mask to decode the line number */
+    public static final int LINE_MASK   = (1 << LINE_BITS) - 1;
+    /** Mask to decode the column number */
+    public static final int COLUMN_MASK = (1 << COLUMN_BITS) - 1;
+
+    /** The undefined position */
+    public static final int NOPOS       = 0;
+
+    /** The first position in a source file */
+    public static final int FIRSTPOS    = encode(1, 1);
+
+    //########################################################################
+    // Public Functions
+
+    /** Encodes a position into a single integer. */
+    public static int encode(int line, int column) {
+        assert line >= 0 : line;
+        assert line == 0 ? column == 0 : column >= 0 : line + "," + column;
+        if (line >= LINE_MASK) { line = LINE_MASK; column = 0; }
+        if (column > COLUMN_MASK) column = COLUMN_MASK;
+        return (line << COLUMN_BITS) | column;
+    }
+
+    /** Returns the line number of the encoded position. */
+    public static int line(int position) {
+        return (position >> COLUMN_BITS) & LINE_MASK;
+    }
+
+    /** Returns the column number of the encoded position. */
+    public static int column(int position) {
+        return position & COLUMN_MASK;
+    }
+
+    /** Returns a string representation of the encoded position. */
+    public static String toString(int position) {
+        return line(position) + ":" + column(position);
+    }
+
+    //########################################################################
+    // Private Fields
+
+    /** The position's file */
+    private final SourceFile file;
+
+    /** The position's line number */
+    private final int line;
+
+    /** The position's column number */
+    private final int column;
+
+    //########################################################################
+    // Public Constructors
+
+    /** Initializes a new instance. */
+    public Position(String source) {
+        this(new SourceFile(source, new byte[0]));
+    }
+
+    /** Initializes a new instance. */
+    public Position(SourceFile file) {
+        this(file, 0, 0);
+    }
+
+    /** Initializes a new instance. */
+    public Position(SourceFile file, int position) {
+        this(file, line(position), column(position));
+    }
+
+    /** Initializes a new instance. */
+    public Position(SourceFile file, int line, int column) {
+        this.file = file;
+        this.line = line;
+        this.column = column;
+        assert file != null;
+        assert line >= 0 : line;
+        assert line == 0 ? column == 0 : column >= 0 : line + "," + column;
+    }
+
+    //########################################################################
+    // Public Methods
+
+    /** Returns the file of this position. */
+    public SourceFile file() {
+        return file;
+    }
+
+    /** Returns the line number of this position. */
+    public int line() {
+        return line;
+    }
+
+    /** Returns the column number of this position. */
+    public int column() {
+        return column;
+    }
+
+    /** Returns an int encoding the line and column of this position. */
+    public int encodedLineColumn() {
+        return encode(line, column);
+    }
+
+    /** Returns a string representation of this position. */
+    public String toString() {
+        StringBuffer buffer = new StringBuffer(file.name());
+        if (line > 0) buffer.append(":").append(line);
+        if (line > 0 && column > 0) buffer.append(":").append(column);
+        return buffer.toString();
+    }
+
+    /** Returns the hash code of this position. */
+    public int hashCode() {
+        return file.hashCode() ^ encodedLineColumn();
+    }
+
+    /** Returns true iff the given object represents the same position. */
+    public boolean equals(Object object) {
+        if (!(object instanceof Position)) return false;
+        Position that = (Position)object;
+        return file == that.file && line == that.line && column == that.column;
+    }
+
+    //########################################################################
+}
diff --git a/sources/scala/tools/util/SourceFile.java b/sources/scala/tools/util/SourceFile.java
new file mode 100644
index 0000000000..1014f7a0f7
--- /dev/null
+++ b/sources/scala/tools/util/SourceFile.java
@@ -0,0 +1,177 @@
+/*     ____ ____  ____ ____  ______                                     *\
+**    / __// __ \/ __// __ \/ ____/    SOcos COmpiles Scala             **
+**  __\_ \/ /_/ / /__/ /_/ /\_ \       (c) 2002, LAMP/EPFL              **
+** /_____/\____/\___/\____/____/                                        **
+\*                                                                      */
+
+// $Id$
+
+package scala.tools.util;
+
+import java.io.File;
+import java.io.InputStream;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.UnsupportedEncodingException;
+import java.util.ArrayList;
+
+
+/** This class represents a single source file.
+ */
+public class SourceFile {
+
+    //########################################################################
+    // Public Constants
+
+    /** Constants used for source parsing */
+    public static final byte LF = 0x0A;
+    public static final byte FF = 0x0C;
+    public static final byte CR = 0x0D;
+    public static final byte SU = 0x1A;
+
+    //########################################################################
+    // Private Fields
+
+    /** The name of this source file */
+    private final String name;
+
+    /** The content of source this file */
+    private final byte[] bytes;
+
+    /** The encoding of this source file or null if unspecified */
+    private String encoding;
+
+    /** The position of the last line returned by getLine */
+    private int lineNumber = 0;
+    private int lineStart  = 0;
+    private int lineLength = 0;
+    private int nextIndex  = 0;
+
+    //########################################################################
+    // Public Constructors
+
+    /** Initializes a new instance. */
+    public SourceFile(String name) throws IOException {
+        this(new File(name));
+    }
+
+    /** Initializes a new instance. */
+    public SourceFile(File name) throws IOException {
+        this(name.toString(), read(name));
+    }
+
+    /** Initializes a new instance. */
+    public SourceFile(String name, InputStream input) throws IOException {
+        this(name, read(name, input));
+    }
+
+    /** Initializes a new instance. */
+    public SourceFile(String name, byte[] bytes) {
+        this.name = name;
+        this.bytes = normalize(bytes);
+    }
+
+    //########################################################################
+    // Public Methods
+
+    /** Returns the name of this source file. */
+    public String name() {
+        return name;
+    }
+
+    /** Returns the content of this source file. */
+    public byte[] bytes() {
+        return bytes;
+    }
+
+    /** Sets the encoding of the file. */
+    public void setEncoding(String encoding) {
+        this.encoding = encoding;
+    }
+
+    /** Returns the short name (name without path) of this source file. */
+    public String getShortName() {
+        int start = name.lastIndexOf(File.separatorChar);
+        return start < 0 ? name : name.substring(start + 1);
+    }
+
+    /**
+     * Returns an instance of Position representing the given line and
+     * column of this source file.
+     */
+    public Position getPosition(int line, int column) {
+        return new Position(this, line, column);
+    }
+
+    /** Returns the content of the given line. */
+    public String getLine(int line) {
+        int index = lineNumber <= line ? nextIndex : (lineNumber = 0);
+        for (; index < bytes.length && lineNumber < line; lineNumber++) {
+            lineStart = index;
+            for (; index < bytes.length; index++) {
+                if (bytes[index] == CR) break;
+                if (bytes[index] == LF) break;
+                if (bytes[index] == FF) break;
+            }
+            lineLength = index - lineStart;
+            if (index < bytes.length)
+            	index++;
+            if (index < bytes.length)
+                if (bytes[index - 1] == CR && bytes[index] == LF) index++;
+        }
+        nextIndex = index;
+        try {
+            return encoding != null ?
+                new String(bytes, lineStart, lineLength, encoding) :
+                new String(bytes, lineStart, lineLength);
+        } catch (UnsupportedEncodingException exception) {
+            throw new Error(exception); // !!! use ApplicationError
+        }
+    }
+
+    /** Returns the name of this source file. */
+    public String toString() {
+        return name;
+    }
+
+    //########################################################################
+    // Private Methods
+
+    /** Reads the file and returns its content as a byte array.
+     */
+    private static byte[] read(File file) throws IOException {
+        InputStream input = new FileInputStream(file);
+        try {
+            return read(file.toString(), input);
+        } finally {
+            input.close();
+        }
+    }
+
+    /** Reads the InputStream and returns its content as a byte array.
+     */
+    private static byte[] read(String name, InputStream input) throws IOException {
+        try {
+            byte[] bytes = new byte[input.available() + 1];
+            int numread = input.read(bytes);
+            if ((numread >= 0) && (numread != bytes.length - 1))
+            	throw new IOException();
+            bytes[bytes.length - 1] = SU;
+            return bytes;
+        } catch (IOException exception) {
+            throw new IOException("cannot read '" + name + "'");
+        }
+    }
+
+    /** Ensures that the last byte of the array is SU. */
+    private static byte[] normalize(byte[] input) {
+        if (input.length > 0 && input[input.length - 1] == SU)
+        	return input;
+        byte[] bytes = new byte[input.length + 1];
+        System.arraycopy(input, 0, bytes, 0, input.length);
+        bytes[input.length] = SU;
+        return bytes;
+    }
+
+    //########################################################################
+}