decoder/DsdLib: dsdlib_skip*() may throw

Prepare for getting detailed seek errors.

Author: MaxKellermann

src/decoder/plugins/DsdLib.cxx

@@ -34,12 +34,8 @@ dsdlib_skip_to(DecoderClient *client, InputStream &is,
 	       offset_type offset)
 {
 	if (is.IsSeekable()) {
-		try {
-			is.LockSeek(offset);
-			return true;
-		} catch (...) {
-			return false;
-		}
+		is.LockSeek(offset);
+		return true;
 	}
 
 	if (is.GetOffset() > offset)
@@ -56,12 +52,8 @@ dsdlib_skip(DecoderClient *client, InputStream &is,
 		return true;
 
 	if (is.IsSeekable()) {
-		try {
-			is.LockSeek(is.GetOffset() + delta);
-			return true;
-		} catch (...) {
-			return false;
-		}
+		is.LockSeek(is.GetOffset() + delta);
+		return true;
 	}
 
 	if (delta > 1024 * 1024)

src/decoder/plugins/DsdLib.hxx

@@ -22,6 +22,8 @@ struct DsdId {
 
 /**
  * Skip the #InputStream to the specified offset.
+ *
+ * On error, either throws exception or returns false.
  */
 [[nodiscard]]
 bool
@@ -30,6 +32,8 @@ dsdlib_skip_to(DecoderClient *client, InputStream &is,
 
 /**
  * Skip some bytes from the #InputStream.
+ *
+ * On error, either throws exception or returns false.
  */
 [[nodiscard]]
 bool

src/decoder/plugins/DsdiffDecoderPlugin.cxx

@@ -377,12 +377,16 @@ dsdiff_decode_chunk(DecoderClient &client, InputStream &is,
 				break;
 			}
 
-			if (dsdlib_skip_to(&client, is,
-					   start_offset + offset)) {
-				client.CommandFinished();
-				remaining_bytes = total_bytes - offset;
-			} else
+			try {
+				if (dsdlib_skip_to(&client, is,
+						   start_offset + offset)) {
+					client.CommandFinished();
+					remaining_bytes = total_bytes - offset;
+				} else
+					client.SeekError();
+			} catch (...) {
 				client.SeekError();
+			}
 		}
 
 		/* see how much aligned data from the remaining chunk

src/decoder/plugins/DsfDecoderPlugin.cxx

@@ -257,11 +257,16 @@ dsf_decode_chunk(DecoderClient &client, InputStream &is,
 
 			offset_type offset =
 				start_offset + block * block_size;
-			if (dsdlib_skip_to(&client, is, offset)) {
-				client.CommandFinished();
-				i = block;
-			} else
+
+			try {
+				if (dsdlib_skip_to(&client, is, offset)) {
+					client.CommandFinished();
+					i = block;
+				} else
+					client.SeekError();
+			} catch (...) {
 				client.SeekError();
+			}
 		}
 
 		/* worst-case buffer size */