Initial import.

T0/BlobWriter.cs

@@ -0,0 +1,112 @@
+/*
+ * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining 
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be 
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+using System;
+using System.IO;
+using System.Text;
+
+/*
+ * A simple class for writing out bytes as hexadecimal constants or
+ * explicit expressions for the initializer of a C array of 'unsigned
+ * char'. It starts every line with a given number of tabs, and aims at
+ * keeping lines below a given threshold (each indentation tab counts as
+ * 8 characters). An explicit newline is inserted before the first
+ * element, and commas are used as separators.
+ */
+
+class BlobWriter {
+
+	TextWriter w;
+	int maxLineLen;
+	int indent;
+	int lineLen;
+
+	/*
+	 * Create a new instance. 'maxLineLen' is in characters, and
+	 * 'indent' is the number of tab characters at the start of
+	 * each line.
+	 */
+	internal BlobWriter(TextWriter w, int maxLineLen, int indent)
+	{
+		this.w = w;
+		this.maxLineLen = maxLineLen;
+		this.indent = indent;
+		lineLen = -1;
+	}
+
+	void DoNL()
+	{
+		w.WriteLine();
+		for (int i = 0; i < indent; i ++) {
+			w.Write('\t');
+		}
+		lineLen = (indent << 3);
+	}
+
+	/*
+	 * Append a new byte value; it will be converted to an hexadecimal
+	 * constant in the output.
+	 */
+	internal void Append(byte b)
+	{
+		if (lineLen < 0) {
+			DoNL();
+		} else {
+			w.Write(',');
+			lineLen ++;
+			if ((lineLen + 5) > maxLineLen) {
+				DoNL();
+			} else {
+				w.Write(' ');
+				lineLen ++;
+			}
+		}
+		w.Write("0x{0:X2}", b);
+		lineLen += 4;
+	}
+
+	/*
+	 * Append a C expression, which will be used as is. The expression
+	 * may resolve to several bytes if it uses internal commas. The
+	 * writer will try to honour the expected line length, but it
+	 * won't insert a newline character inside the expression.
+	 */
+	internal void Append(string expr)
+	{
+		if (lineLen < 0) {
+			DoNL();
+		} else {
+			w.Write(',');
+			lineLen ++;
+			if ((lineLen + 1 + expr.Length) > maxLineLen) {
+				DoNL();
+			} else {
+				w.Write(' ');
+				lineLen ++;
+			}
+		}
+		w.Write("{0}", expr);
+		lineLen += expr.Length;
+	}
+}