Added support for Garmin IMG maps

src/map/IMG/subfile.cpp

@@ -0,0 +1,76 @@
+#include "img.h"
+#include "subfile.h"
+
+SubFile::Type SubFile::type(const char str[3])
+{
+	if (!memcmp(str, "TRE", 3))
+		return TRE;
+	else if (!memcmp(str, "RGN", 3))
+		return RGN;
+	else if (!memcmp(str, "LBL", 3))
+		return LBL;
+	else if (!memcmp(str, "TYP", 3))
+		return TYP;
+	else if (!memcmp(str, "GMP", 3))
+		return GMP;
+	else if (!memcmp(str, "NET", 3))
+		return NET;
+	else
+		return Unknown;
+}
+
+bool SubFile::isValid() const
+{
+	return ((quint32)_img->blockSize() * (quint32)_blocks.size() - _size
+	  < (quint32)_img->blockSize());
+}
+
+bool SubFile::seek(Handle &handle, quint32 pos) const
+{
+	quint32 blockSize = _img->blockSize();
+	int blockNum = pos / blockSize;
+
+	if (handle.blockNum != blockNum) {
+		if (blockNum >= _blocks.size())
+			return false;
+		handle.data = _img->readBlock(_blocks.at(blockNum));
+		if (handle.data.isNull())
+			return false;
+		handle.blockNum = blockNum;
+	}
+
+	handle.blockPos = pos % blockSize;
+	handle.pos = pos;
+
+	return true;
+}
+
+bool SubFile::readByte(Handle &handle, quint8 &val) const
+{
+	val = handle.data.at(handle.blockPos++);
+	handle.pos++;
+	return (handle.blockPos >= _img->blockSize())
+	  ? seek(handle, handle.pos) : true;
+}
+
+const QString &SubFile::imgName() const
+{
+	return _img->name();
+}
+
+#ifndef QT_NO_DEBUG
+QDebug operator<<(QDebug dbg, const SubFile &file)
+{
+	bool continuous = true;
+	for (int i = 1; i < file._blocks.size(); i++) {
+		if (file._blocks.at(i) != file._blocks.at(i-1) + 1) {
+			continuous = false;
+			break;
+		}
+	}
+
+	dbg.nospace() << "SubFile(" << file._size << ", " << file._blocks.size()
+	  << ", " << continuous << ")";
+	return dbg.space();
+}
+#endif // QT_NO_DEBUG