X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=blobdiff_plain;f=source%2Fio%2Fslice.cpp;h=59a7cde301b463d492fb79ef11733702d60d512e;hp=904f748668e472257ae383dd93330cc8fc3d4299;hb=169ece8b190040c4b61d68122c4ead1ba266cf79;hpb=0793fb99ee8c55c7ffe96bca902632f328e10edb

diff --git a/source/io/slice.cpp b/source/io/slice.cpp
index 904f748..59a7cde 100644
--- a/source/io/slice.cpp
+++ b/source/io/slice.cpp
@@ -16,6 +16,7 @@ Slice::Slice(Seekable &b, SeekOffset s, SeekOffset l):
 	if(s<0 || l<0)
 		throw invalid_argument("Slice");
 
+	Base::Synchronize sync(below);
 	mode = below.get_mode()&M_RDWR;
 	below.signal_flush_required.connect(sigc::mem_fun(this, &Slice::flush));
 }
@@ -30,7 +31,12 @@ unsigned Slice::prepare_op(unsigned size, Mode m)
 	check_access(m);
 
 	if(sync_position)
-		seek(position, S_BEG);
+	{
+		SeekOffset pos = below.seek(start_offset+position, S_BEG)-start_offset;
+		if(pos!=position)
+			throw runtime_error("failed to restore position");
+		sync_position = false;
+	}
 
 	SeekOffset remaining = start_offset+length-position;
 	if(size>remaining)
@@ -43,6 +49,7 @@ unsigned Slice::prepare_op(unsigned size, Mode m)
 
 unsigned Slice::do_write(const char *data, unsigned size)
 {
+	Base::Synchronize sync(below);
 	size = prepare_op(size, M_WRITE);
 	if(!size)
 		return 0;
@@ -54,6 +61,7 @@ unsigned Slice::do_write(const char *data, unsigned size)
 
 unsigned Slice::do_read(char *data, unsigned size)
 {
+	Base::Synchronize sync(below);
 	size = prepare_op(size, M_READ);
 	if(!size)
 		return 0;
@@ -67,6 +75,7 @@ unsigned Slice::do_read(char *data, unsigned size)
 
 unsigned Slice::put(char c)
 {
+	Base::Synchronize sync(below);
 	if(!prepare_op(1, M_WRITE))
 		return 0;
 
@@ -77,6 +86,7 @@ unsigned Slice::put(char c)
 
 int Slice::get()
 {
+	Base::Synchronize sync(below);
 	if(!prepare_op(1, M_READ))
 		return 0;
 
@@ -90,6 +100,7 @@ int Slice::get()
 
 SeekOffset Slice::seek(SeekOffset off, SeekType type)
 {
+	Base::Synchronize sync(below);
 	off += start_offset;
 	if(type==S_CUR)
 		off += position;